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Sample records for electrochemical lithium insertion

  1. Highly Reversible Electrochemical Insertion of Lithium, Accompanied With a Marked Color Change, Occuring in Microcrystalline Lithium Nickel Oxide Films

    OpenAIRE

    Campet, G.; Portier, J.; Morel, B.; Ferry, D.; Chabagno, J. M.; Benotmane, L.; Bourrel, M.

    1992-01-01

    Thin films of lithium-nickel oxide, whose texture consists of microcrystallites with an average grain size of 50 Å, permit highly reversible electrochemical insertion of lithium ions in Li+ conducting electrolytes. Therefore, the corresponding materials would be of great interest for energy storage applications. In addition, the lithium insertion/extraction reactions in the nickel-based layers are accompanied with a marked color change, making these films of interest for the devel...

  2. Electrochemical study of lithium insertion into carbon-rich polymer-derived silicon carbonitride ceramics

    International Nuclear Information System (INIS)

    Kaspar, Jan; Mera, Gabriela; Nowak, Andrzej P.; Graczyk-Zajac, Magdalena; Riedel, Ralf

    2010-01-01

    This paper presents the lithium insertion into carbon-rich polymer-derived silicon carbonitride (SiCN) ceramic synthesized by the thermal treatment of poly(diphenylsilylcarbodiimide) at three temperatures, namely 1100, 1300, and 1700 o C under 0.1 MPa Ar atmosphere. At lower synthesis temperatures, the material is X-ray amorphous, while at 1700 o C, the SiCN ceramic partially crystallizes. Anode materials prepared from these carbon-rich SiCN ceramics without any fillers and conducting additives were characterized using cyclic voltammetry and chronopotentiometric charging/discharging. We found that the studied silicon carbonitride ceramics demonstrate a promising electrochemical behavior during lithium insertion/extraction in terms of capacity and cycling stability. The sample synthesized at 1300 o C exhibits a reversible capacity of 392 mAh g -1 . Our study confirms that carbon-rich SiCN phases are electrochemically active materials in terms of Li inter- and deintercalation.

  3. Fracture of crystalline silicon nanopillars during electrochemical lithium insertion

    KAUST Repository

    Lee, S. W.

    2012-02-27

    From surface hardening of steels to doping of semiconductors, atom insertion in solids plays an important role in modifying chemical, physical, and electronic properties of materials for a variety of applications. High densities of atomic insertion in a solid can result in dramatic structural transformations and associated changes in mechanical behavior: This is particularly evident during electrochemical cycling of novel battery electrodes, such as alloying anodes, conversion oxides, and sulfur and oxygen cathodes. Silicon, which undergoes 400% volume expansion when alloying with lithium, is an extreme case and represents an excellent model system for study. Here, we show that fracture locations are highly anisotropic for lithiation of crystalline Si nanopillars and that fracture is strongly correlated with previously discovered anisotropic expansion. Contrary to earlier theoretical models based on diffusion-induced stresses where fracture is predicted to occur in the core of the pillars during lithiation, the observed cracks are present only in the amorphous lithiated shell. We also show that the critical fracture size is between about 240 and 360 nm and that it depends on the electrochemical reaction rate.

  4. Chemical and electrochemical lithium insertion into ternary transition metal sulfides MMo[sub 2]S[sub 4] (M: V, Cr, Fe)

    Energy Technology Data Exchange (ETDEWEB)

    Maffi, S.; Peraldo Bicelli, L. (Milan Polytechnic (Italy). Dept. of Applied Physical Chemistry CNR, Milan (Italy). Research Centre on Electrode Processes); Barriga, C.; Lavela, P.; Morales, J.; Tirado, J.L. (Cordoba Univ. (Spain). Dept. de Quimica Inorganica e Ingenieria Quimica)

    1992-08-01

    The effects of lithium insertion in MMo[sub 2]S[sub 4] (M: V, Cr, Fe) have been studied by means of chemical and electrochemical insertion methods. The reaction has a topotactic character and a higher degree of lithium insertion was found for the compound FeMo[sub 2]S[sub 4] which has a greater unit cell volume. For this compound the changes in lattice parameters with lithium content are also more pronounced. The voltage composition curves show a smooth voltage decrease with a quasi-plateau located at around 1.3 V. For discharge at lithium content higher than 0.8, the voltage decreases quickly followed by an extended plateau below 1 V, a region where electrolyte decomposition may occur. The X-ray powder diffraction patterns of the electrochemical lithiated compounds show that the original monoclinic structure is maintained up to 0.8 e[sup -] per mole, buth with a significant change in the intensity of the peaks, indicative of an alteration of cation distribution for this degree of insertion. For high lithium content, such disorder promotes the collapse of the structure, resulting in the loss of long-range order of the material. (orig.).

  5. Lithium Insertion in LixMn2O4, 0

    DEFF Research Database (Denmark)

    West, Keld; Zachau-Christiansen, Birgit; Skaarup, Steen

    1996-01-01

    The electrochemical lithium insertion properties of highly crystalline LixMn2O4 are investigated in the approximate lithium insertion range 0 ... of the lithium insertion/extraction reactions is better at the higher voltages (versus Li/Li+), and particularly at the 4 V plateau. The lithium insertion/extraction reaction at the 1 V plateau although essentially reversible is associated with a significant voltage hysteresis....

  6. Behavior of the monophosphate tungsten bronzes (PO2)4(WO3)2m (m = 7 and 8) in the course of electrochemical lithium insertion

    International Nuclear Information System (INIS)

    Martinez-de la Cruz, A.; Longoria Rodriguez, F.E.; Gonzalez, Lucy T.; Torres-Martinez, Leticia M.

    2007-01-01

    The electrochemical lithium insertion process has been studied in the family of monophosphate tungsten bronzes (PO 2 ) 4 (WO 3 ) 2m , where m = 7 and 8. Structural changes in the pristine oxides were followed as lithium insertion proceeded. Through potentiostatic intermittent technique the different processes which take place in the cathode during the discharge of the cell were analyzed. The nature of the bronzes Li x (PO 2 ) 4 (WO 3 ) 2m formed was determined by in situ X-ray diffraction experiments. These results have allowed establishing a correlation with the reversible/irreversible processes detected during the electrochemical lithium insertion

  7. Study of the lithium insertion-deinsertion mechanism in nanocrystalline γ-Fe2O3 electrodes by means of electrochemical impedance spectroscopy

    International Nuclear Information System (INIS)

    Quintin, M.; Devos, O.; Delville, M.H.; Campet, G.

    2006-01-01

    Lithium intercalation hosts are a key point to the energy density of the largely used LiCoO 2 (even if of high cost and toxicity) as well as of manganese oxides which have been investigated most extensively. Iron oxides are attractive electrode materials for low-voltage rechargeable lithium batteries from both cost and environmental standpoints. However, search for iron oxides of conventional crystalline structures and micrometer particle sizes as lithium intercalation cathodes, has been greeted with disappointing results. Here we report on the synthesis, characterizations, electrochemical study and electrochemical impedance spectroscopy (EIS) of a nanocrystalline γ-Fe 2 O 3 that simultaneously exhibits high lithium insertion capacity and good capacity retention upon cycling. These properties reveal thermodynamics of the nanocrystalline material inherently different from those of its microcrystalline counterpart. Moreover, EIS showed that the intercalation process of the lithium ion occurs according to two processes involving first the reduction of the surface Fe 3+ with concomitant charge neutralization by Li + ions onto the surface defects of the nanoparticle followed by the reduction of the core Fe 3+ with insertion of the Li + deeper in the particle

  8. Studies on electrochemical lithium insertion in isostructural titanium niobate and tantalate phases with shear ReO3 structure

    International Nuclear Information System (INIS)

    Saritha, D.; Varadaraju, U.V.

    2013-01-01

    Graphical abstract: - Highlights: • Electrochemical lithium insertion into ReO 3 type phases TiNb 2 O 7 , TiTa 2 O 7 is feasible. • TiNb 2 O 7 exhibits good cycling behavior and high reversible capacity of 212 mAh g −1 . • TiTa 2 O 7 exhibits reversible capacity of 100 mAh g −1 . - Abstract: TiNb 2 O 7 and TiTa 2 O 7 phases are synthesized by solid-state reaction method and are investigated for electrochemical Li insertion/extraction. The electrochemical insertion of Li in these phases is characterized by both solid solution and two-phase regimes. The structure is stable toward Li insertion/extraction. The first cycle discharge capacity values are 307 mAh g −1 and 215 mAh g −1 in the voltage range of 3.0–1.0 V for TiNb 2 O 7 and TiTa 2 O 7 phases, respectively. The discharge capacities of TiNb 2 O 7 and TiTa 2 O 7 are 212 mAh g −1 and 100 mAh g −1 , respectively, after 20 cycles

  9. Electrochemical lithium insertion in graphite containing dispersed tin-antimony alloys

    Energy Technology Data Exchange (ETDEWEB)

    Billaud, Denis; Nabais, Catarina; Mercier, Cedric [LCSM, Laboratoire de Chimie du Solide Mineral, Nancy University, BP 239, 54506 Vandoeuvre les Nancy Cedex (France); Schneider, Raphael [LCPME, Laboratoire de Chimie Physique et Microbiologie pour l' Environnement, Nancy University, Faculte de Pharmacie, BP 80 403, 54001 Nancy Cedex (France); Willmann, Patrick [CNES, Centre National d' Etudes Spatiales, 18, Avenue E. Belin, 31055 Toulouse Cedex (France)

    2008-09-15

    Graphite/SnSb composites were prepared by solution-phase reduction of SnCl{sub 2} and SbCl{sub 5} in the presence of graphite powder using either t-BuONa-activated NaH or t-BuOLi-activated LiH. Crude and washed materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and field emission gun-scanning electron microscopy (FEG-SEM). Electrochemical lithium insertion was carried out in both types of composites using voltammetry or galvanostatic charge/discharge techniques. It appeared that graphite-SnSb composites prepared using t-BuOLi-activated LiH as reductant displayed the highest reversible capacity (ca. 500 mA h g{sup -1}). This phenomenon is likely in relation with a better dispersion and grafting of metal particles on graphite, as suggested by FEG-SEM and TEM analyses. However, such dispersion appeared to increase significantly the irreversible capacity. (author)

  10. High performance lithium insertion negative electrode materials for electrochemical devices

    Energy Technology Data Exchange (ETDEWEB)

    Channu, V.S. Reddy, E-mail: chinares02@gmail.com [SMC Corporation, College Station, TX 77845 (United States); Rambabu, B. [Solid State Ionics and Surface Sciences Lab, Department of Physics, Southern University and A& M College, Baton Rouge, LA 70813 (United States); Kumari, Kusum [Department of Physics, National Institute of Technology, Warangal (India); Kalluru, Rajmohan R. [The University of Southern Mississippi, College of Science and Technology, 730 E Beach Blvd, Long Beach, MS 39560 (United States); Holze, Rudolf [Institut für Chemie, AG Elektrochemie, Technische Universität Chemnitz, D-09107 Chemnitz (Germany)

    2016-11-30

    Highlights: • LiCrTiO{sub 4} nanostructures were synthesized for electrochemical applications by soft chemical synthesis followed by annealing. • The presence of Cr and Ti elements are confirmed from the EDS spectrum. • Oxalic acid assisted LiCrTiO{sub 4} electrode shows higher specific capacity (mAh/g). - Abstract: Spinel LiCrTiO{sub 4} oxides to be used as electrode materials for a lithium ion battery and an asymmetric supercapacitor were synthesized using a soft-chemical method with and without chelating agents followed by calcination at 700 °C for 10 h. Structural and morphological properties were studied with powder X-ray diffraction, scanning electron and transmission electron microscopy. Particles of 50–10 nm in size are observed in the microscopic images. The presence of Cr and Ti is confirmed from the EDS spectrum. Electrochemical properties of LiCrTiO{sub 4} electrode were examined in a lithium ion battery. The electrode prepared with oxalic acid-assisted LiCrTiO{sub 4} shows higher specific capacity.This LiCrTiO{sub 4} is also used as anode material for an asymmetric hybrid supercapacitor. The cell exhibits a specific capacity of 65 mAh/g at 1 mA/cm{sup 2}. The specific capacity decreases with increasing current densities.

  11. Synthesis, characterization and electrochemical performances of new antimony-containing graphite compounds used as anodes for lithium-ion batteries

    International Nuclear Information System (INIS)

    Dailly, A.; Willmann, P.; Billaud, D.

    2002-01-01

    Graphite intercalation intercalated with metal alloys able to alloy reversibly lithium constitute a large set of new anodic materials for lithium-ion batteries of significantly improved reversible capacities. Especially, graphite intercalated with cesium-antimony alloys can be used as materials for anodes in lithium-ion batteries. Electrochemical insertion of lithium in such chemically modified precursors shows that lithium both intercalates in the empty van der Waals spaces of graphite and alloys reversibly with antimony. The total electrochemical reversible capacities, measured between 0 and 2 V vs Li + /Li, close to 700 mAh g -1 have been currently obtained

  12. Synthesis and electrochemical sodium and lithium insertion properties of sodium titanium oxide with the tunnel type structure

    Science.gov (United States)

    Kataoka, Kunimitsu; Akimoto, Junji

    2016-02-01

    Polycrystalline sample of sodium titanium oxide Na2Ti4O9 with the tunnel-type structure was prepared by topotactic sodium extraction in air atmosphere from the as prepared Na3Ti4O9 sample. The starting Na3Ti4O9 compound was synthesized by solid state reaction at 1273 K in Ar atmosphere. The completeness of oxidation reaction from Na3Ti4O9 to Na2Ti4O9 was monitored by the change in color from dark blue to white, and was also confirmed by the Rietveld refinement using the powder X-ray diffraction data. The sodium deficient Na2Ti4O9 maintained the original Na2.08Ti4O9-type tunnel structure and had the monoclinic crystal system, space group C2/m, and the lattice parameters of a = 23.1698(3) Å, b = 2.9406(1) Å, c = 10.6038(2) Å, β = 102.422(3)°, and V = 705.57(2) Å3. The electrochemical measurements of thus obtained Na2Ti4O9 sample showed the reversible sodium insertion and extraction reactions at 1.1 V, 1.5 V, and 1.8 V vs. Na/Na+, and reversible lithium insertion and extraction reactions at around 1.4 V, 1.8 V, and 2.0 V vs. Li/Li+. The reversible capacity for the lithium cell was achieved to be 104 mAh g-1 at the 100th cycle.

  13. In situ57Fe Moessbauer Investigation of Solid-State Redox Reactions of Lithium Insertion Electrodes for Advanced Batteries

    International Nuclear Information System (INIS)

    Sakai, Yoichi; Ariyoshi, Kingo; Ohzuku, Tsutomu

    2002-01-01

    A novel in situ electrochemical cell for 57 Fe Moessbauer measurements was developed in order to clarify the mechanisms of solid-state redox reactions in lithium insertion materials containing iron. Our in situ Moessbauer technique was successfully applied to the determination as to which transition metal ion was a redox center in the insertion electrodes, such as LiFe 0.5 Mn 1.5 O 4 , LiFeTiO 4 , or LiFe 0.25 Ni 0.75 O 2 , for the lithium-ion batteries.

  14. A Simple Synthesis of Two-Dimensional Ultrathin Nickel Cobaltite Nanosheets for Electrochemical Lithium Storage

    International Nuclear Information System (INIS)

    Zhu, Youqi; Cao, Chuanbao

    2015-01-01

    We report a simple microwave-assisted method to fabricate high-quality two-dimensional (2D) ultrathin NiCo 2 O 4 nanosheets with a geometrically graphene-like architecture. The unique large-area nanostructures represent an ultrahigh surface atomic ratio with almost all active elements exposed outside for surface-dependent electrochemical reaction processes. Experimental results reveal that the as-synthesized ultrathin NiCo 2 O 4 nanosheets show excellent electrochemical performances for lithium storage application. The ultrathin NiCo 2 O 4 nanosheets could deliver a high first discharge capacity (1287.1 mAh g −1 ) with initial Coulombic efficiency of 80.0% at 200 mA g −1 current density. The reversible lithium storage capacity still retains at 804.8 mAh g −1 in the 100th cycle, suggesting a good cycling stability. The excellent electrochemical properties of the as-synthesized NiCo 2 O 4 nanosheets could be ascribed to the unique ultrathin 2D architecture, which could offer large exposed active surface with more lithium-insertion channels and significantly reduce lithium ion diffusion distance. The cost-efficient synthesis and excellent lithium storage properties make the 2D NiCo 2 O 4 nanosheets as a promising anode material for high-performance lithium ion batteries

  15. Lithium insertion in the two crystallographic forms of the binary-phase Mo15Se19

    Science.gov (United States)

    Tarascon, J. M.; Murphy, D. W.

    1986-02-01

    Compounds which can undergo topotactic insertion of lithium are of potential technological importance in secondary lithium batteries. In this paper we present the chemical and electrochemical insertion of lithium into the binary-phase Mo15Se19, which can exist in two crystallographic forms, denoted AA and BB, when prepared from In3Mo15Se19 and In2Mo15Se19, respectively. We show that both forms can reversibly accommodate up to eight lithium atoms, yielding two new series of compounds of formula LixMo15Se19. This behavior is consistent with the electronic structure of the host material predicted from band-structure calculations. The room-temperature phase diagram of both LixMo15Se19 systems as a function of x has been established using electrochemical test cells (based on Mo15Se19 as the cathode), and in situ x-ray measurements as the cells discharge. Both LixMo15Se19 systems contain three single-phase domains as a function of x: two hexagonal phases and an orthorhombic phase. The nature of the transitions between these single phases and the variation of the lattice parameters within a single-phase domain are reported. While the mechanism of intercalation of lithium is similar for both Mo15Se19 forms, there is a drastic difference in Li intercalation behavior for the parent indium phases In2Mo15Se19 and In3Mo15Se19. We found that In2Mo15Se19 can reversibly incorporate 6.4 lithium atoms while In3Mo15Se19 does not react. This behavior is explained on the basis of structural considerations.

  16. Electrochemical and spectroscopic characterization of lithium titanate spinel Li{sub 4}Ti{sub 5}O{sub 12}

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Holger; Maire, Pascal [Paul Scherrer Institut, Electrochemistry Laboratory, Section Electrochemical Energy Storage, CH-5232 Villigen PSI (Switzerland); Novak, Petr, E-mail: petr.novak@psi.ch [Paul Scherrer Institut, Electrochemistry Laboratory, Section Electrochemical Energy Storage, CH-5232 Villigen PSI (Switzerland)

    2011-10-30

    Herein we describe electrochemical and spectroscopic properties of lithium titanate spinel as well as an easy method based on colorimetry to determine the lithium content of electrodes containing lithium titanate spinel as active material. Raman microspectrometry measurements have been performed to follow lithium insertion into and extraction from the active material, respectively. The Raman signals display a pronounced fading of intensity already at low levels of lithium intercalation and disappear at a SOC higher than {approx}10%. However, the colorimetric method can be used up to a SOC of 50%.

  17. The investigation on electrochemical reaction mechanism of CuF2 thin film with lithium

    International Nuclear Information System (INIS)

    Cui Yanhua; Xue Mingzhe; Zhou Yongning; Peng Shuming; Wang Xiaolin; Fu Zhengwen

    2011-01-01

    Crystalline CuF 2 thin films were prepared by pulsed laser deposition under room temperature. The physical and electrochemical properties of the as-deposited thin films have been investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), galvanostatic cycling and cyclic voltammetry (CV). Reversible capacity of 544 mAh g -1 was achieved in the potential range of 1.0-4.0 V. A reversible couple of redox peaks at 3.0 V and 3.7 V was firstly observed. By using ex situ XRD and TEM techniques, an insertion process followed by a fully conversion reaction to Cu and LiF was revealed in the lithium electrochemical reaction of CuF 2 thin film electrode. The reversible insertion reaction above 2.8 V could provide a capacity of about 125 mAh g -1 , which makes CuF 2 a potential cathode material for rechargeable lithium batteries.

  18. Electrochemical reactivity of Co-Li2S nanocomposite for lithium-ion batteries

    International Nuclear Information System (INIS)

    Zhou, Yongning; Wu, Changliang; Zhang, Hua; Wu, Xiaojing; Fu, Zhengwen

    2007-01-01

    The fabrication of Co-Li 2 S nanocomposite thin film is reported by pulsed laser deposition (PLD) for the first time. Li 2 S-Co nanocomposite thin film is used as storing Li electrodes that have led to promising electrochemical activity and good electrochemical performance. The releasing Li process from the as-deposited Li 2 S-Co nanocomposite thin films is confirmed by the ex situ high resolution transmission electron microscopy (HR-TEM) and selected area electron diffraction (SAED) measurements and may come from the decomposition of Li 2 S with and without the interaction of metal Co into CoS 2 and S. The electrochemical reaction mechanism of Co-Li 2 S nanocomposite film electrode involving both the formation and decomposition of Li 2 S and the lithium extraction/insertion of CoS 2 after the initial charging process is proposed. Our results demonstrate the advantages of using Co-Li 2 S nanocomposite in storage lithium materials

  19. Lithium insertion in the two crystallographic forms of the binary-phase Mo15Se19

    International Nuclear Information System (INIS)

    Tarascon, J.M.; Murphy, D.W.

    1986-01-01

    Compounds which can undergo topotactic insertion of lithium are of potential technological importance in secondary lithium batteries. In this paper we present the chemical and electrochemical insertion of lithium into the binary-phase Mo 15 Se 19 , which can exist in two crystallographic forms, denoted AA and BB, when prepared from In 3 Mo 15 Se 19 and In 2 Mo 15 Se 19 , respectively. We show that both forms can reversibly accommodate up to eight lithium atoms, yielding two new series of compounds of formula Li/sub x/Mo 15 Se 19 . This behavior is consistent with the electronic structure of the host material predicted from band-structure calculations. The room-temperature phase diagram of both Li/sub x/Mo 15 Se 19 systems as a function of x has been established using electrochemical test cells (based on Mo 15 Se 19 as the cathode), and in situ x-ray measurements as the cells discharge. Both Li/sub x/Mo 15 Se 19 systems contain three single-phase domains as a function of x: two hexagonal phases and an orthorhombic phase. The nature of the transitions between these single phases and the variation of the lattice parameters within a single-phase domain are reported. While the mechanism of intercalation of lithium is similar for both Mo 15 Se 19 forms, there is a drastic difference in Li intercalation behavior for the parent indium phases In''Mo 15 Se 19 and In 3 Mo 15 Se 19 . We found that In 2 Mo 15 Se 19 can reversibly incorporate 6.4 lithium atoms while In 3 Mo 15 Se 19 does not react. This behavior is explained on the basis of structural considerations

  20. Controllable synthesis of porous LiFePO4 for tunable electrochemical Li-insertion performance

    International Nuclear Information System (INIS)

    Tian, Xiaohui; Zhou, Yingke; Wu, Guan; Wang, Pengcheng; Chen, Jian

    2017-01-01

    Highlights: • A templated freeze-drying method is developed to prepare the porous LiFePO 4 . • The pore size and porosity can be controlled by adjusting the conditions. • The effects of the porous properties on the Li-insertion performances are studied. • The optimized composite presents excellent specific capacity and rate capability. - Abstract: A templated freeze-drying method is developed to prepare the porous LiFePO 4 materials with the controlled pore size and porosity, by conveniently adjusting the size and content of the template in the precursor solution. The morphology and structure of the porous LiFePO 4 materials are characterized and the relavant electrochemical lithium-insertion performances are systematically studied. It’s found that the porous characteristics play a critical role in the lithium-ion intercalation processes and significantly affect the power capability of LiFePO 4 . The optimized porous LiFePO 4 material presents remarkable specific capacity (167 mAh g −1 at 0.1 C), rate capability (151 mAh g −1 at 1 C and 110 mAh g −1 at 10 C) and cycling stability (99.3% retention after 300 cycles at 1 C). These findings demonstrate that the electrochemical performance of the electrode material can be purposely tuned and remarkably improved by the rational design and introduction of the suitable pores, which open up new strategies for the synthesis of advanced porous materials for the lithium-ion power battery applications.

  1. A fundamental approach to better understand the lithium insertion mechanisms in electrode materials; Une approche fondamentale pour mieux comprendre les mecanismes d`insertion du lithium dans les materiaux d`electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Olivier-Fourcade, J.; Branci, C.; Sarradin, J.; Jumas, J.C. [Montpellier-2 Univ., 34 (France). Laboratoire de Physicochimie de la Matiere Condensee

    1996-12-31

    The development of rechargeable lithium batteries with a high mass capacity, made with non-toxic and low cost materials is an important industrial challenge. Morphological and structural modifications occurring in the electrode materials during charge-output cycles should not lower the electrochemical characteristics and the cycling properties of the battery. Thus the structure of electrode materials must be sufficiently deformable and stable to support the constraints linked with lithium intercalation and de-intercalation (ions and electrons absorption/extraction). The aim of this work is to explain some characteristics (mass capacity, ions and electrons mobility, cycling) using the relation between some mechanisms of lithium insertion (sites occupation, lattice reduction mods) and the nature of atoms and chemical bonds (covalence, ionicity). This approach is developed on 2-D models of crystallized and vitreous sulfur compounds (CdI{sub 2} type) with a large inter-sheet distance, and on 3-D spinel models with a huge number of vacant sites. The method is based on a correlation between experimental studies (XAFS, DX, Moessbauer, XPS) and theoretical calculations and on the electronic and electrochemical characteristics. The model proposed should allow to improve materials in a predictive way (type of substitution) or to imagine new materials. (J.S.) 15 refs.

  2. A fundamental approach to better understand the lithium insertion mechanisms in electrode materials; Une approche fondamentale pour mieux comprendre les mecanismes d`insertion du lithium dans les materiaux d`electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Olivier-Fourcade, J; Branci, C; Sarradin, J; Jumas, J C [Montpellier-2 Univ., 34 (France). Laboratoire de Physicochimie de la Matiere Condensee

    1997-12-31

    The development of rechargeable lithium batteries with a high mass capacity, made with non-toxic and low cost materials is an important industrial challenge. Morphological and structural modifications occurring in the electrode materials during charge-output cycles should not lower the electrochemical characteristics and the cycling properties of the battery. Thus the structure of electrode materials must be sufficiently deformable and stable to support the constraints linked with lithium intercalation and de-intercalation (ions and electrons absorption/extraction). The aim of this work is to explain some characteristics (mass capacity, ions and electrons mobility, cycling) using the relation between some mechanisms of lithium insertion (sites occupation, lattice reduction mods) and the nature of atoms and chemical bonds (covalence, ionicity). This approach is developed on 2-D models of crystallized and vitreous sulfur compounds (CdI{sub 2} type) with a large inter-sheet distance, and on 3-D spinel models with a huge number of vacant sites. The method is based on a correlation between experimental studies (XAFS, DX, Moessbauer, XPS) and theoretical calculations and on the electronic and electrochemical characteristics. The model proposed should allow to improve materials in a predictive way (type of substitution) or to imagine new materials. (J.S.) 15 refs.

  3. Electrochemical reactivity of ilmenite FeTiO3, its nanostructures and oxide-carbon nanocomposites with lithium

    International Nuclear Information System (INIS)

    Tao, Tao; Glushenkov, Alexey M.; Rahman, Md Mokhlesur; Chen, Ying

    2013-01-01

    The electrochemical reactivity of the ball-milled ilmenite FeTiO 3 and ilmenite nanoflowers with lithium has been investigated. The electrode assembled with the ilmenite nanoflowers delivers better electrochemical performance than that of the milled material during charging and discharging in the potential range of 0.01 and 3 V vs. Li/Li + . The ilmenite nanoflowers demonstrate the capacity of ca. 650 mAh g −1 during the first discharge, and a reversible capacity of approximately 200 mAh g −1 in the course of the first 50 cycles. The possible reaction mechanism between ilmenite and lithium was studied using cyclic voltammetry and transmission electron microscopy. The first discharge involves the formation of an irreversible phase, which is either LiTiO 2 or LiFeO 2 . Subsequently, the extraction–insertion of lithium happens in a reversible manner. It was also observed that the lithium storage might be significantly improved if the electrode was prepared in the form of a nanocomposite of FeTiO 3 with carbon

  4. Topotactic insertion of lithium in the layered structure Li4VO(PO4)2: The tunnel structure Li5VO(PO4)2

    International Nuclear Information System (INIS)

    Satya Kishore, M.; Pralong, V.; Caignaert, V.; Malo, S.; Hebert, S.; Varadaraju, U.V.; Raveau, B.

    2008-01-01

    A new V(III) lithium phosphate Li 5 VO(PO 4 ) 2 has been synthesized by electrochemical insertion of lithium into Li 4 VO(PO 4 ) 2 . This phase, which crystallizes in the space group I4/mcm, exhibits a tunnel structure closely related to the layered structure of Li 4 VO(PO 4 ) 2 and to the tunnel structure of VO(H 2 PO 4 ) 2 . The topotactic reactions that take place during lithium exchange and intercalation, starting from VO(H 2 PO 4 ) 2 and going to the final phase Li 5 VO(PO 4 ) 2 are explained on the basis of the flexible coordinations of V 4+ and V 3+ species. The electrochemical and magnetic properties of this new phase are also presented and explained on the basis of the structure dimensionality. - Graphical abstract: Electrochemical synthesis of a new 3D V(III) lithium phosphate, Li 5 VO(PO 4 ) 2 . Starting from the 2D Li 4 VO(PO 4 ) 2 , the topotactic reaction that take place during lithium intercalation is explained on the basis of the flexible coordinations of V 4+ and V 3+ species

  5. Lithium isotope effect accompanying electrochemical intercalation of lithium into graphite

    CERN Document Server

    Yanase, S; Oi, T

    2003-01-01

    Lithium has been electrochemically intercalated from a 1:2 (v/v) mixed solution of ethylene carbonate (EC) and methylethyl carbonate (MEC) containing 1 M LiClO sub 4 into graphite, and the lithium isotope fractionation accompanying the intercalation was observed. The lighter isotope was preferentially fractionated into graphite. The single-stage lithium isotope separation factor ranged from 1.007 to 1.025 at 25 C and depended little on the mole ratio of lithium to carbon of the lithium-graphite intercalation compounds (Li-GIC) formed. The separation factor increased with the relative content of lithium. This dependence seems consistent with the existence of an equilibrium isotope effect between the solvated lithium ion in the EC/MEC electrolyte solution and the lithium in graphite, and with the formation of a solid electrolyte interfaces on graphite at the early stage of intercalation. (orig.)

  6. Lithium Insertion In Silicon Nanowires: An ab Initio Study

    KAUST Repository

    Zhang, Qianfan; Zhang, Wenxing; Wan, Wenhui; Cui, Yi; Wang, Enge

    2010-01-01

    The ultrahigh specific lithium ion storage capacity of Si nanowires (SiNWs) has been demonstrated recently and has opened up exciting opportunities for energy storage. However, a systematic theoretical study on lithium insertion in SiNWs remains a

  7. Electrochemical performance of CuNCN for sodium ion batteries and comparison with ZnNCN and lithium ion batteries

    Science.gov (United States)

    Eguia-Barrio, A.; Castillo-Martínez, E.; Klein, F.; Pinedo, R.; Lezama, L.; Janek, J.; Adelhelm, P.; Rojo, T.

    2017-11-01

    Transition metal carbodiimides (TMNCN) undergo conversion reactions during electrochemical cycling in lithium and sodium ion batteries. Micron sized copper and zinc carbodiimide powders have been prepared as single phase as confirmed by PXRD and IR and their thermal stability has been studied in air and nitrogen atmosphere. CuNCN decomposes at ∼250 °C into CuO or Cu while ZnNCN can be stable until 400 °C and 800 °C in air and nitrogen respectively. Both carbodiimides were electrochemically analysed for sodium and lithium ion batteries. The electrochemical Na+ insertion in CuNCN exhibits a relatively high reversible capacity (300 mAh·g-1) which still indicates an incomplete conversion reaction. This incomplete reaction confirmed by ex-situ EPR analysis, is partly due to kinetic limitations as evidenced in the rate capability experiments and in the constant potential measurements. On the other hand, ZnNCN shows incomplete conversion reaction but with good capacity retention and lower hysteresis as negative electrode for sodium ion batteries. The electrochemical performance of these materials is comparable to that of other materials which operate through displacement reactions and is surprisingly better in sodium ion batteries in comparison with lithium ion batteries.

  8. Lithium Insertion In Silicon Nanowires: An ab Initio Study

    KAUST Repository

    Zhang, Qianfan

    2010-09-08

    The ultrahigh specific lithium ion storage capacity of Si nanowires (SiNWs) has been demonstrated recently and has opened up exciting opportunities for energy storage. However, a systematic theoretical study on lithium insertion in SiNWs remains a challenge, and as a result, understanding of the fundamental interaction and microscopic dynamics during lithium insertion is still lacking. This paper focuses on the study of single Li atom insertion into SiNWs with different sizes and axis orientations by using full ab initio calculations. We show that the binding energy of interstitial Li increases as the SiNW diameter grows. The binding energies at different insertion sites, which can be classified as surface, intermediate, and core sites, are quite different. We find that surface sites are energetically the most favorable insertion positions and that intermediate sites are the most unfavorable insertion positions. Compared with the other growth directions, the [110] SiNWs with different diameters always present the highest binding energies on various insertion locations, which indicates that [110] SiNWs are more favorable by Li doping. Furthermore, we study Li diffusion inside SiNWs. The results show that the Li surface diffusion has a much higher chance to occur than the surface to core diffusion, which is consistent with the experimental observation that the Li insertion in SiNWs is layer by layer from surface to inner region. After overcoming a large barrier crossing surface-to-intermediate region, the diffusion toward center has a higher possibility to occur than the inverse process. © 2010 American Chemical Society.

  9. Lithium Insertion in LiCr3O8, NaCr3O8, and KCr3O8 at Room Temperature and at 125°C

    DEFF Research Database (Denmark)

    Koksbang, R.; Fauteux, D.; Norby, P.

    1989-01-01

    Lithium insertion and deinsertion reactions have been carried out with LiCr3O8, NaCr3O8, and KCr3O8 chemically andelectrochemically at room temperature and at 125°C. The electrochemical experiments were performed with a nonaqueousliquid electrolyte at room temperature and with a polymer electroly...... is close to 4Li/NaCr3O8 and 1.3Li/KCr3O8.Lithium ion diffusion coefficients are similar for the two compounds in the comparable composition range.Thermally, the fully lithiated compounds appear to be as stable as the pristine materials.......Lithium insertion and deinsertion reactions have been carried out with LiCr3O8, NaCr3O8, and KCr3O8 chemically andelectrochemically at room temperature and at 125°C. The electrochemical experiments were performed with a nonaqueousliquid electrolyte at room temperature and with a polymer electrolyte....... At elevated temperatures, the isostructural compounds NaCr3O8 and KCr3O8 are able to accommodate morethan 4Li/MCr3O8. During this process, minor structural changes are observed. At room temperature, NaCr3O8 and KCr3O8also accommodate Li topotactically, but the maximum number of Li inserted per formula...

  10. Electrochemical insertion in solid media of alkali cations in carbonated host structures (polyacetylene, fullerene and graphite)

    International Nuclear Information System (INIS)

    Lemont, Sylvain

    1994-01-01

    This research thesis reports the investigation of electrochemical insertion of alkali cations in different host carbon containing structures (polyacetylene, fullerene, graphite). After a recall of the main characteristics of the three considered compounds, the author reports a bibliographical survey, describes the different compounds which can be used as solid electrolytes and explains the choice of the studied compounds with respect to their phase diagrams, ionic conductivity, electrochemical stability range. He describes the experimental methods, discusses the results obtained by intercalation of alkali cations (Li + , Na + , K + ) in polyacetylene. He discusses the electrochemical and structural results obtained on intercalation compounds of lithium and sodium ions in fullerene. The structures of several phases have been obtained by electron diffraction. Preliminary studies of electron energy loss spectrometry (EELS) are reported. The last part compares the results obtained on two types of graphite: pellets and spherules [fr

  11. Lithium insertion mechanism in SnS2

    International Nuclear Information System (INIS)

    Lefebvre-Devos, I.; Olivier-Fourcade, J.; Jumas, J.C.; Lavela, P.

    2000-01-01

    We study lithium insertion in SnS 2 by means of 119 Sn Moessbauer spectroscopy, x-ray absorption spectroscopy at Sn L I,III , and S K edges, and theoretical electronic structures (calculated in the density-functional theory framework). An insertion mechanism is derived according to the Li amount. It shows the influence of the SnS 2 -layered structure on the Sn reduction, particularly the possibility of an intermediate oxidation state between Sn IV and Sn II , which is not observed during Li insertion in three-dimensional sulfides

  12. Lithium insertion in sputtered vanadium oxide film

    DEFF Research Database (Denmark)

    West, K.; Zachau-Christiansen, B.; Skaarup, S.V.

    1992-01-01

    were oxygen deficient compared to V2O5. Films prepared in pure argon were reduced to V(4) or lower. The vanadium oxide films were tested in solid-state lithium cells. Films sputtered in oxygen showed electrochemical properties similar to crystalline V2O5. The main differences are a decreased capacity...

  13. Lithium insertion in V{sub 2}O{sub 5}, M{sub x}V{sub 2}O{sub 5} (M = Fe, Cr, Al, La) mixed oxides; Insertion du lithium dans les oxydes mixtes de V{sub 2}O{sub 5}, M{sub x}V{sub 2}O{sub 5} (M = Fe, Cr, Al, La)

    Energy Technology Data Exchange (ETDEWEB)

    Gregoire, G.; Pecquenard, B.; Baffier, N. [Centre National de la Recherche Scientifique (CNRS), 75 - Paris (France). Laboratoire de Chimie Appliquee de l`Etat Solide; Soudan, P.; Farcy, J.; Pereira-Ramos, J.P. [Centre National de la Recherche Scientifique (CNRS), 94 - Ivry-sur-Seine (France). Laboratoire d`Electrochimie Catalyse et Synthese Organique

    1996-12-31

    V{sub 2}O{sub 5} based compounds are interesting low potential materials for rechargeable cathodes of lithium electrochemical generators. However, the ionic conductivity and the reversibility of electrochemical cycling of V{sub 2}O{sub 5} are limited by the possibilities of lithium insertion. This work shows that the doping of vanadium pentoxide by a M{sup 3+} trivalent transition element (M Fe, Al, Cr or La) allows to intercalate a more important amount of lithium and to improve the behaviour of the material during cycling. These materials of M{sub 0.11}V{sub 2}O{sub 5.16} formula are obtained by sol-gel synthesis. the electrochemical study of the Fe compound has shown that it is a mixed oxide with a behaviour similar to V{sub 2}O{sub 5}. The maximum capacity is of about 2 F/mole in the case of Fe, Al and Cr compounds and of about 1.7 F/mole in the case of La. The structural evolution of the Fe compound has been followed during the chemical insertion of Li and the same succession of phases ({alpha}, {epsilon}, {delta} and {gamma}) is observed as in Li{sub x}V{sub 2}O{sub 5} compounds but with a delay. The occurrence of the {gamma} phase, in particular, which is involved in recharging problems is delayed thanks to the (Fe-O){sub n} chains perpendicular to the (V{sub 2}O{sub 5}){sub n} layers. Abstract only. (J.S.) 3 refs.

  14. Lithium insertion in V{sub 2}O{sub 5}, M{sub x}V{sub 2}O{sub 5} (M = Fe, Cr, Al, La) mixed oxides; Insertion du lithium dans les oxydes mixtes de V{sub 2}O{sub 5}, M{sub x}V{sub 2}O{sub 5} (M = Fe, Cr, Al, La)

    Energy Technology Data Exchange (ETDEWEB)

    Gregoire, G; Pecquenard, B; Baffier, N [Centre National de la Recherche Scientifique (CNRS), 75 - Paris (France). Laboratoire de Chimie Appliquee de l` Etat Solide; Soudan, P; Farcy, J; Pereira-Ramos, J P [Centre National de la Recherche Scientifique (CNRS), 94 - Ivry-sur-Seine (France). Laboratoire d` Electrochimie Catalyse et Synthese Organique

    1997-12-31

    V{sub 2}O{sub 5} based compounds are interesting low potential materials for rechargeable cathodes of lithium electrochemical generators. However, the ionic conductivity and the reversibility of electrochemical cycling of V{sub 2}O{sub 5} are limited by the possibilities of lithium insertion. This work shows that the doping of vanadium pentoxide by a M{sup 3+} trivalent transition element (M Fe, Al, Cr or La) allows to intercalate a more important amount of lithium and to improve the behaviour of the material during cycling. These materials of M{sub 0.11}V{sub 2}O{sub 5.16} formula are obtained by sol-gel synthesis. the electrochemical study of the Fe compound has shown that it is a mixed oxide with a behaviour similar to V{sub 2}O{sub 5}. The maximum capacity is of about 2 F/mole in the case of Fe, Al and Cr compounds and of about 1.7 F/mole in the case of La. The structural evolution of the Fe compound has been followed during the chemical insertion of Li and the same succession of phases ({alpha}, {epsilon}, {delta} and {gamma}) is observed as in Li{sub x}V{sub 2}O{sub 5} compounds but with a delay. The occurrence of the {gamma} phase, in particular, which is involved in recharging problems is delayed thanks to the (Fe-O){sub n} chains perpendicular to the (V{sub 2}O{sub 5}){sub n} layers. Abstract only. (J.S.) 3 refs.

  15. Lithium insertion into Fe 2(SO 4) 3 frameworks

    Science.gov (United States)

    Manthiram, A.; Goodenough, J. B.

    1989-05-01

    The two polymorphs of Fe 2(SO 4) 3 consist of framework structures built up of tetrahedra sharing corners with octahedra and vice versa. One is rhombohedral, the other is monoclinic. Two moles of lithium insert rapidly into both structures at room temperature. However, lithium insertion into the rhombohedral phase is topotactic without any change of symmetry of the framework, whereas the monoclinic modification is converted to an orthorombic Li 2Fe 2(SO 4) 3 phase via a displacement transition; the existence of a two-phase region between Fe 2(SO 4) 3 and Li 2Fe 2(SO 4) 3 results in a flat OCV of 3.6 V versus lithium, which is 600 mV higher than is found for Li xFFe 2(WO 4) 3 or Li xFe 2(MoO 4) 3. This difference is discussed in terms of the influence of the counter cation on the solid-state Fe {3+}/{2+} redox couple.

  16. Graphene-supported SnO2 nanoparticles prepared by a solvothermal approach for an enhanced electrochemical performance in lithium-ion batteries.

    Science.gov (United States)

    Wang, Bei; Su, Dawei; Park, Jinsoo; Ahn, Hyojun; Wang, Guoxiu

    2012-04-13

    SnO2 nanoparticles were dispersed on graphene nanosheets through a solvothermal approach using ethylene glycol as the solvent. The uniform distribution of SnO2 nanoparticles on graphene nanosheets has been confirmed by scanning electron microscopy and transmission electron microscopy. The particle size of SnO2 was determined to be around 5 nm. The as-synthesized SnO2/graphene nanocomposite exhibited an enhanced electrochemical performance in lithium-ion batteries, compared with bare graphene nanosheets and bare SnO2 nanoparticles. The SnO2/graphene nanocomposite electrode delivered a reversible lithium storage capacity of 830 mAh g-1 and a stable cyclability up to 100 cycles. The excellent electrochemical properties of this graphene-supported nanocomposite could be attributed to the insertion of nanoparticles between graphene nanolayers and the optimized nanoparticles distribution on graphene nanosheets.

  17. Carbon-Based Materials for Lithium-Ion Batteries, Electrochemical Capacitors, and Their Hybrid Devices.

    Science.gov (United States)

    Yao, Fei; Pham, Duy Tho; Lee, Young Hee

    2015-07-20

    A rapidly developing market for portable electronic devices and hybrid electrical vehicles requires an urgent supply of mature energy-storage systems. As a result, lithium-ion batteries and electrochemical capacitors have lately attracted broad attention. Nevertheless, it is well known that both devices have their own drawbacks. With the fast development of nanoscience and nanotechnology, various structures and materials have been proposed to overcome the deficiencies of both devices to improve their electrochemical performance further. In this Review, electrochemical storage mechanisms based on carbon materials for both lithium-ion batteries and electrochemical capacitors are introduced. Non-faradic processes (electric double-layer capacitance) and faradic reactions (pseudocapacitance and intercalation) are generally explained. Electrochemical performance based on different types of electrolytes is briefly reviewed. Furthermore, impedance behavior based on Nyquist plots is discussed. We demonstrate the influence of cell conductivity, electrode/electrolyte interface, and ion diffusion on impedance performance. We illustrate that relaxation time, which is closely related to ion diffusion, can be extracted from Nyquist plots and compared between lithium-ion batteries and electrochemical capacitors. Finally, recent progress in the design of anodes for lithium-ion batteries, electrochemical capacitors, and their hybrid devices based on carbonaceous materials are reviewed. Challenges and future perspectives are further discussed. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Study of surface reaction of spinel Li4Ti5O12 during the first lithium insertion and extraction processes using atomic force microscopy and analytical transmission electron microscopy.

    Science.gov (United States)

    Kitta, Mitsunori; Akita, Tomoki; Maeda, Yasushi; Kohyama, Masanori

    2012-08-21

    Spinel lithium titanate (Li(4)Ti(5)O(12), LTO) is a promising anode material for a lithium ion battery because of its excellent properties such as high rate charge-discharge capability and life cycle stability, which were understood from the viewpoint of bulk properties such as small lattice volume changes by lithium insertion. However, the detailed surface reaction of lithium insertion and extraction has not yet been studied despite its importance to understand the mechanism of an electrochemical reaction. In this paper, we apply both atomic force microscopy (AFM) and transmission electron microscopy (TEM) to investigate the changes in the atomic and electronic structures of the Li(4)Ti(5)O(12) surface during the charge-discharged (lithium insertion and extraction) processes. The AFM observation revealed that irreversible structural changes of an atomically flat Li(4)Ti(5)O(12) surface occurs at the early stage of the first lithium insertion process, which induces the reduction of charge transfer resistance at the electrolyte/Li(4)Ti(5)O(12) interface. The TEM observation clarified that cubic rock-salt crystal layers with a half lattice size of the original spinel structure are epitaxially formed after the first charge-discharge cycle. Electron energy loss spectroscopy (EELS) observation revealed that the formed surface layer should be α-Li(2)TiO(3). Although the transformation of Li(4)Ti(5)O(12) to Li(7)Ti(5)O(12) is well-known as the lithium insertion reaction of the bulk phase, the generation of surface product layers should be inevitable in real charge-discharge processes and may play an effective role in the stable electrode performance as a solid-electrolyte interphase (SEI).

  19. Electrochemical Performance of Electrospun carbon nanofibers as free-standing and binder-free anodes for Sodium-Ion and Lithium-Ion Batteries

    International Nuclear Information System (INIS)

    Jin, Juan; Shi, Zhi-qiang; Wang, Cheng-yang

    2014-01-01

    Highlights: • Electrospun carbon nanofiber webs were prepared by pyrolysis of polyacrylonitrile. • The webs as binder-free and current collector-free electrodes for SIBs and LIBs. • Different layer spacing and pore size for Li and Na lead different electrochemical behavior. • Electrochemical performances of the electrodes were high. - Abstract: A series of hard carbon nanofiber-based electrodes derived from electrospun polyacrylonitrile (PAN) nanofibers (PAN-CNFs) have been fabricated by stabilization in air at about 280 °C and then carbonization in N 2 at heat treatment temperatures (HTT) between 800 and 1500 °C. The electrochemical performances of the binder-free, current collector-free carbon nanofiber-based anodes in lithium-ion batteries and sodium-ion batteries are systematically investigated and compared. We demonstrate the presence of similar alkali metal insertion mechanisms in both cases, but just the differences of the layer spacing and pore size available for lithium and sodium ion lead the discharge capacity delivered at sloping region and plateau region to vary from the kinds of alkali elements. Although the anodes in sodium-ion batteries show poorer rate capability than that in lithium-ion batteries, they still achieve a reversible sodium intercalation capacity of 275 mAh g −1 and similar cycling stability due to the conductive 3-D network, weakly ordered turbostratic structure and a large interlayer spacing between graphene sheets. The feature of high capacity and stable cycling performance makes PAN-CNFs to be promising candidates as electrodes in rechargeable sodium-ion batteries and lithium-ion batteries

  20. An electrochemical cell for in operando studies of lithium/sodium batteries using a conventional x-ray powder diffractometer

    DEFF Research Database (Denmark)

    Shen, Yanbin; Pedersen, Erik Ejler; Christensen, Mogens

    2014-01-01

    An electrochemical cell has been designed for powder X-ray diffraction (PXRD) studies of lithium ion batteries (LIB) and sodium ion batteries (SIB) in operando with high time resolution using conventional powder X-ray diffractometer. The cell allows for studies of both anode and cathode electrode...... to operate and maintain. Test examples on lithium insertion/extraction in two spinel-type LIB electrode materials (Li4Ti5O12 anode and LiMn2O4 cathode) are presented as well as first results on sodium extraction from a layered SIB cathode material (Na0.84Fe0.56Mn0.44O2)....

  1. Simulation of electrochemical behavior in Lithium ion battery during discharge process.

    Science.gov (United States)

    Chen, Yong; Huo, Weiwei; Lin, Muyi; Zhao, Li

    2018-01-01

    An electrochemical Lithium ion battery model was built taking into account the electrochemical reactions. The polarization was divided into parts which were related to the solid phase and the electrolyte mass transport of species, and the electrochemical reactions. The influence factors on battery polarization were studied, including the active material particle radius and the electrolyte salt concentration. The results showed that diffusion polarization exist in the positive and negative electrodes, and diffusion polarization increase with the conducting of the discharge process. The physicochemical parameters of the Lithium ion battery had the huge effect on cell voltage via polarization. The simulation data show that the polarization voltage has close relationship with active material particle size, discharging rate and ambient temperature.

  2. Structural and electrochemical study of the reaction of lithium with silicon nanowires

    KAUST Repository

    Chan, Candace K.; Ruffo, Riccardo; Hong, Seung Sae; Huggins, Robert A.; Cui, Yi

    2009-01-01

    The structural transformations of silicon nanowires when cycled against lithium were evaluated using electrochemical potential spectroscopy and galvanostatic cycling. During the charge, the nanowires alloy with lithium to form an amorphous Lix

  3. Cycle aging studies of lithium nickel manganese cobalt oxide-based batteries using electrochemical impedance spectroscopy

    NARCIS (Netherlands)

    Maheshwari, Arpit; Heck, Michael; Santarelli, Massimo

    2018-01-01

    The cycle aging of a commercial 18650 lithium-ion battery with graphite anode and lithium nickel manganese cobalt (NMC) oxide-based cathode at defined operating conditions is studied by regular electrochemical characterization, electrochemical impedance spectroscopy (EIS) and post-mortem analysis.

  4. Insertion of Mono- vs. Bi- vs. Trivalent Atoms in Prospective Active Electrode Materials for Electrochemical Batteries: An ab Initio Perspective

    Directory of Open Access Journals (Sweden)

    Vadym V. Kulish

    2017-12-01

    Full Text Available Rational design of active electrode materials is important for the development of advanced lithium and post-lithium batteries. Ab initio modeling can provide mechanistic understanding of the performance of prospective materials and guide design. We review our recent comparative ab initio studies of lithium, sodium, potassium, magnesium, and aluminum interactions with different phases of several actively experimentally studied electrode materials, including monoelemental materials carbon, silicon, tin, and germanium, oxides TiO2 and VxOy as well as sulphur-based spinels MS2 (M = transition metal. These studies are unique in that they provided reliable comparisons, i.e., at the same level of theory and using the same computational parameters, among different materials and among Li, Na, K, Mg, and Al. Specifically, insertion energetics (related to the electrode voltage and diffusion barriers (related to rate capability, as well as phononic effects, are compared. These studies facilitate identification of phases most suitable as anode or cathode for different types of batteries. We highlight the possibility of increasing the voltage, or enabling electrochemical activity, by amorphization and p-doping, of rational choice of phases of oxides to maximize the insertion potential of Li, Na, K, Mg, Al, as well as of rational choice of the optimum sulfur-based spinel for Mg and Al insertion, based on ab initio calculations. Some methodological issues are also addressed, including construction of effective localized basis sets, applications of Hubbard correction, generation of amorphous structures, and the use of a posteriori dispersion corrections.

  5. Electrochemical properties of ether-based electrolytes for lithium/sulfur rechargeable batteries

    International Nuclear Information System (INIS)

    Barchasz, Céline; Leprêtre, Jean-Claude; Patoux, Sébastien; Alloin, Fannie

    2013-01-01

    Highlights: ► Liquid electrolyte composition for lithium/sulfur secondary batteries. ► Carbonate-based electrolytes prove not to be compatible with the sulfur electrode. ► Poor electrochemical performances related to low polysulfide solubility. ► Increase in the discharge capacity using ether solvents with high solvating ability such as PEGDME. ► Evidence of DIOX polymerization during cycling. -- Abstract: The lithium/sulfur (Li/S) battery is a promising electrochemical system that has a high theoretical capacity of 1675 mAh g −1 . However, the system suffers from several drawbacks: poor active material conductivity, active material dissolution, and use of the highly reactive lithium metal electrode. In this study, we investigated the electrolyte effects on electrochemical performances of the Li/S cell, by acting on the solvent composition. As conventional carbonate-based electrolytes turned out to be unusable in Li/S cells, alternative ether solvents had to be considered. Different kinds of solvent structures were investigated by changing the ether/alkyl moieties ratio to vary the lithium polysulfide solubility. This allowed to point out the importance of the solvent solvation ability on the discharge capacity. As the end of discharge is linked to the positive electrode passivation, an electrolyte having high solvation ability reduces the polysulfide precipitation and delays the positive electrode passivation

  6. The electrochemical performance and mechanism of cobalt (II) fluoride as anode material for lithium and sodium ion batteries

    International Nuclear Information System (INIS)

    Tan, Jinli; Liu, Li; Guo, Shengping; Hu, Hai; Yan, Zichao; Zhou, Qian; Huang, Zhifeng; Shu, Hongbo; Yang, Xiukang; Wang, Xianyou

    2015-01-01

    Highlights: •The as-prepared CoF 2 shows excellent electrochemical performance as anode material for lithium ion batteries. •The Li insertion/extraction mechanism of CoF 2 below 1.2 V was firstly proposed. •The electrochemical performance of CoF 2 as anode material in sodium ion batteries was firstly studied. -- Abstract: Cobalt (II) fluoride begins to enter into the horizons of people along with the research upsurge of metal fluorides. It is very significative and theoretically influential to make certain its electrochemical reaction mechanism. In this work, we discover a new and unrevealed reversible interfacial intercalation mechanism reacting below 1.2 V for cobalt (II) fluoride electrode material, which contributes a combined discharge capacity of about 400 mA h g −1 with the formation of SEI film at the initial discharge process. A highly reversible storage capacity of 120 mA h g −1 is observed when the cell is cycled over the voltage of 0.01-1.2 V at 0.2 C, and the low-potential voltage reaction process has a significant impact for the whole electrochemical process. Electrochemical analyses suggest that pure cobalt (II) fluoride shows better electrochemical performance when it is cycled at 3.2-0.01 V compared to the high range (1.0-4.5 V). So, we hold that cobalt (II) fluoride is more suitable to serve as anode material for lithium ion batteries. In addition, we also try to reveal the relevant performance and reaction mechanism, and realize the possibility of cobalt (II) fluoride as anode material for sodium ion batteries

  7. MnO2 prepared by hydrothermal method and electrochemical performance as anode for lithium-ion battery.

    Science.gov (United States)

    Feng, Lili; Xuan, Zhewen; Zhao, Hongbo; Bai, Yang; Guo, Junming; Su, Chang-Wei; Chen, Xiaokai

    2014-01-01

    Two α-MnO2 crystals with caddice-clew-like and urchin-like morphologies are prepared by the hydrothermal method, and their structure and electrochemical performance are characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), galvanostatic cell cycling, cyclic voltammetry, and electrochemical impedance spectroscopy (EIS). The morphology of the MnO2 prepared under acidic condition is urchin-like, while the one prepared under neutral condition is caddice-clew-like. The identical crystalline phase of MnO2 crystals is essential to evaluate the relationship between electrochemical performances and morphologies for lithium-ion battery application. In this study, urchin-like α-MnO2 crystals with compact structure have better electrochemical performance due to the higher specific capacity and lower impedance. We find that the relationship between electrochemical performance and morphology is different when MnO2 material used as electrochemical supercapacitor or as anode of lithium-ion battery. For lithium-ion battery application, urchin-like MnO2 material has better electrochemical performance.

  8. Fracture of crystalline silicon nanopillars during electrochemical lithium insertion

    KAUST Repository

    Lee, S. W.; McDowell, M. T.; Berla, L. A.; Nix, W. D.; Cui, Y.

    2012-01-01

    in a solid can result in dramatic structural transformations and associated changes in mechanical behavior: This is particularly evident during electrochemical cycling of novel battery electrodes, such as alloying anodes, conversion oxides, and sulfur

  9. Vanadium based amorphous mixed oxides used as negative electrodes of lithium batteries; Oxydes mixtes amorphes a base de vanadium comme electrodes negatives de batteries au lithium

    Energy Technology Data Exchange (ETDEWEB)

    Guyomard, D.; Leroux, F.; Sigala, C.; Le Gal La Salle, A.; Piffard, Y. [Institut des Materiaux de Nantes, 44 (France). Laboratoire de Chimie des Solides

    1996-12-31

    This paper presents recent results concerning the chemical and electrochemical synthesis, the electrochemical properties and the characterization of two new families of amorphous oxides of formula Li{sub x}MVO{sub 4} (1insertion of lithium and can be used as negative electrodes in high performance lithium-ion batteries. (J.S.) 19 refs.

  10. Vanadium based amorphous mixed oxides used as negative electrodes of lithium batteries; Oxydes mixtes amorphes a base de vanadium comme electrodes negatives de batteries au lithium

    Energy Technology Data Exchange (ETDEWEB)

    Guyomard, D; Leroux, F; Sigala, C; Le Gal La Salle, A.; Piffard, Y [Institut des Materiaux de Nantes, 44 (France). Laboratoire de Chimie des Solides

    1997-12-31

    This paper presents recent results concerning the chemical and electrochemical synthesis, the electrochemical properties and the characterization of two new families of amorphous oxides of formula Li{sub x}MVO{sub 4} (1insertion of lithium and can be used as negative electrodes in high performance lithium-ion batteries. (J.S.) 19 refs.

  11. Insertion of lead lithium eutectic mixture in RELAP/SCDAPSIM Mod 4.0 for Fusion Reactor Systems

    International Nuclear Information System (INIS)

    Tiwari, Ashutosh; Allison, Brian; Hohorst, J.K.; Wagner, R.J.; Allison, Chris

    2012-01-01

    Highlights: ► Thermodynamic and transport properties of lead lithium eutectic mixture have been inserted in RELAP/SCDAPSIM MOD 4.0 code. ► Code results are verified for a simple pipe problem with lead lithium eutectic mixture flowing in it. ► Code is calculating the inserted properties of lead lithium eutectic mixture to a fairly good agreement. - Abstract: RELAP/SCDAPSIM Mod 4.0 code was developed by Innovative System Software (ISS) for the analysis of nuclear power plants (NPPs) cooled by light water and heavy water. Later on the code was expanded to analyze the NPPs cooled by liquid metal, in this sequence: lead bismuth eutectic mixture, liquid sodium and lead lithium eutectic mixture (LLE) are inserted in the code. This paper focuses on the insertion of liquid LLE as a coolant for NPPs in the RELAP/SCDAPSIM Mod 4.0 code. Evaluation of the code was made for a simple pipe problem connected with heat structures having liquid LLE as a coolant in it. The code is predicting well all the thermodynamic and transport properties of LLE.

  12. In situ NMR observation of the lithium extraction/insertion from LiCoO2 cathode

    International Nuclear Information System (INIS)

    Shimoda, Keiji; Murakami, Miwa; Takamatsu, Daiko; Arai, Hajime; Uchimoto, Yoshiharu; Ogumi, Zempachi

    2013-01-01

    Abstract: Rechargeable lithium-ion batteries (LIBs) are currently accepted to be one of the most suitable energy storage resources in portable electronic devices because of their high gravimetric and volumetric energy density. To understand the behavior of Li + ions on electrochemical lithium extraction/insertion process, we performed in situ 7 Li nuclear magnetic resonance (NMR) measurements for LiCoO 2 cathode in a plastic cell battery, and the spectral evolutions of the 7 Li NMR signal of Li x CoO 2 (0 ≤ x ≤ 1) were well investigated. Very narrow solid solution region of Li x CoO 2 (∼0.99 ≤ x 2 signal at ∼0 ppm, which is related to the localized nature of the electronic spin of paramagnetic Co 4+ ion formed at the very early delithiation stage. With further decreasing the signal intensity of LiCoO 2 , a Knight-shifted signal corresponding to an electrically conductive Li x CoO 2 phase emerged at x = 0.97, which then monotonously decreased in intensity for x x CoO 2 . These observations acquired in situ fully confirm the earlier studies obtained in ex situ measurements, although the present study offers more quantitative information. Moreover, it was shown that the peak position of the NMR shift for Li x CoO 2 moved as a function of lithium content, which behavior is analogous to the change in its c lattice parameter. Also, the growth and consumption of dendritic/mossy metallic lithium on the counter electrode was clearly observed during the charge/discharge cycles

  13. High-Resolution Tracking Asymmetric Lithium Insertion and Extraction and Local Structure Ordering in SnS2.

    Science.gov (United States)

    Gao, Peng; Wang, Liping; Zhang, Yu-Yang; Huang, Yuan; Liao, Lei; Sutter, Peter; Liu, Kaihui; Yu, Dapeng; Wang, En-Ge

    2016-09-14

    In the rechargeable lithium ion batteries, the rate capability and energy efficiency are largely governed by the lithium ion transport dynamics and phase transition pathways in electrodes. Real-time and atomic-scale tracking of fully reversible lithium insertion and extraction processes in electrodes, which would ultimately lead to mechanistic understanding of how the electrodes function and why they fail, is highly desirable but very challenging. Here, we track lithium insertion and extraction in the van der Waals interactions dominated SnS2 by in situ high-resolution TEM method. We find that the lithium insertion occurs via a fast two-phase reaction to form expanded and defective LiSnS2, while the lithium extraction initially involves heterogeneous nucleation of intermediate superstructure Li0.5SnS2 domains with a 1-4 nm size. Density functional theory calculations indicate that the Li0.5SnS2 is kinetically favored and structurally stable. The asymmetric reaction pathways may supply enlightening insights into the mechanistic understanding of the underlying electrochemistry in the layered electrode materials and also suggest possible alternatives to the accepted explanation of the origins of voltage hysteresis in the intercalation electrode materials.

  14. Iron phosphate materials as cathodes for lithium batteries

    CERN Document Server

    Prosini, Pier Paolo

    2011-01-01

    ""Iron Phosphate Materials as Cathodes for Lithium Batteries"" describes the synthesis and the chemical-physical characteristics of iron phosphates, and presents methods of making LiFePO4 a suitable cathode material for lithium-ion batteries. The author studies carbon's ability to increase conductivity and to decrease material grain size, as well as investigating the electrochemical behaviour of the materials obtained. ""Iron Phosphate Materials as Cathodes for Lithium Batteries"" also proposes a model to explain lithium insertion/extraction in LiFePO4 and to predict voltage profiles at variou

  15. Electrochemically fabricated polypyrrole-cobalt-oxygen coordination complex as high-performance lithium-storage materials.

    Science.gov (United States)

    Guo, Bingkun; Kong, Qingyu; Zhu, Ying; Mao, Ya; Wang, Zhaoxiang; Wan, Meixiang; Chen, Liquan

    2011-12-23

    Current lithium-ion battery (LIB) technologies are all based on inorganic electrode materials, though organic materials have been used as electrodes for years. Disadvantages such as limited thermal stability and low specific capacity hinder their applications. On the other hand, the transition metal oxides that provide high lithium-storage capacity by way of electrochemical conversion reaction suffer from poor cycling stability. Here we report a novel high-performance, organic, lithium-storage material, a polypyrrole-cobalt-oxygen (PPy-Co-O) coordination complex, with high lithium-storage capacity and excellent cycling stability. Extended X-ray absorption fine structure and Raman spectroscopy and other physical and electrochemical characterizations demonstrate that this coordination complex can be electrochemically fabricated by cycling PPy-coated Co(3)O(4) between 0.0 V and 3.0 V versus Li(+)/Li. Density functional theory (DFT) calculations indicate that each cobalt atom coordinates with two nitrogen atoms within the PPy-Co coordination layer and the layers are connected with oxygen atoms between them. Coordination weakens the C-H bonds on PPy and makes the complex a novel lithium-storage material with high capacity and high cycling stability. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Electrochemical behavior of LiCoO2 as aqueous lithium-ion battery electrodes

    KAUST Repository

    Ruffo, Riccardo

    2009-02-01

    Despite the large number of studies on the behavior of LiCoO2 in organic electrolytes and its recent application as a positive electrode in rechargeable water battery prototypes, a little information is available about the lithium intercalation reaction in this layered compound in aqueous electrolytes. This work shows that LiCoO2 electrodes can be reversibly cycled in LiNO3 aqueous electrolytes for tens of cycles at remarkably high rates with impressive values specific capacity higher than 100 mAh/g, and with a coulomb efficiency greater than 99.7%. Stable and reproducible cycling measurements have been made using a simple cell design that can be easily applied to the study of other intercalation materials, assuming that they are stable in water and that their intercalation potential range matches the electrochemical stability window of the aqueous electrolyte. The experimental arrangement uses a three-electrode flooded cell in which another insertion compound acts as a reversible source and sink of lithium ions, i.e., as the counter electrode. A commercial reference electrode is also present. Both the working and the counter electrodes have been prepared as thin layers on a metallic substrate using the procedures typical for the study of electrodes for lithium-ion batteries in organic solvent electrolytes. © 2008 Elsevier B.V. All rights reserved.

  17. AC impedance electrochemical modeling of lithium-ion positive electrodes

    International Nuclear Information System (INIS)

    Dees, D.; Gunen, E.; Abraham, D.; Jansen, A.; Prakash, J.

    2004-01-01

    Under Department of Energy's Advanced Technology Development Program,various analytical diagnostic studies are being carried out to examine the lithium-ion battery technology for hybrid electric vehicle applications, and a series of electrochemical studies are being conducted to examine the performance of these batteries. An electrochemical model was developed to associate changes that were observed in the post-test analytical diagnostic studies with the electrochemical performance loss during testing of lithium ion batteries. While both electrodes in the lithium-ion cell have been studied using a similar electrochemical model, the discussion here is limited to modeling of the positive electrode. The positive electrode under study has a composite structure made of a layered nickel oxide (LiNi 0.8 Co 0.15 Al 0.05 O 2 ) active material, a carbon black and graphite additive for distributing current, and a PVDF binder all on an aluminum current collector. The electrolyte is 1.2M LiPF 6 dissolved in a mixture of EC and EMC and a Celgard micro-porous membrane is used as the separator. Planar test cells (positive/separator/negative) were constructed with a special fixture and two separator membranes that allowed the placement of a micro-reference electrode between the separator membranes (1). Electrochemical studies including AC impedance spectroscopy were then conducted on the individual electrodes to examine the performance and ageing effects in the cell. The model was developed by following the work of Professor Newman at Berkeley (2). The solid electrolyte interface (SEI) region, based on post-test analytical results, was assumed to be a film on the oxide and an oxide layer at the surface of the oxide. A double layer capacity was added in parallel with the Butler-Volmer kinetic expression. The pertinent reaction, thermodynamic, and transport equations were linearized for a small sinusoidal perturbation (3). The resulting system of differential equations was solved

  18. Comparative electrochemical sodium insertion/extraction behavior in layered NaxVS2 and NaxTiS2

    International Nuclear Information System (INIS)

    Lee, Eungje; Sahgong, SunHye; Johnson, Christopher S.; Kim, Youngsik

    2014-01-01

    This study investigates the electrochemical sodium insertion/extraction of Na x VS 2 , and Na x TiS 2 in the voltage range where either intercalation (0.2 ≤ x ≤ 1) or displacement-conversion reaction (x > 1) occurs. Both Na x VS 2 and Na x TiS 2 showed good reversible capacities, as high as ∼160 mAh/g at an average voltage of ∼1.9 V vs. Na in the region for the intercalation reaction (0.2 ≤ x ≤ 1). When sodium (Na) insertion was forced further to the x > 1 composition, Na x VS 2 exhibited the direct displacement-conversion reaction at 0.3 V vs. Na without further Na intercalation, which contrasted with the wider lithium intercalation range of 0 < x ≤ 2 for Li x VS 2 . The displacement-conversion reaction for Na x VS 2 (x > 1) was reversible with a specific capacity of above 200 mAh/g up to 15 cycles, but the displacement reaction for Na x TiS 2 (x > 1) was not observed

  19. Electrical insulation properties of RF-sputtered LiPON layers towards electrochemical stability of lithium batteries

    OpenAIRE

    Vieira, E. M. F.; Ribeiro, J. F.; Silva, Maria Manuela; Barradas, N. P.; Alves, E.; Alves, A.; Correia, M. R.; Gonçalves, L. M.

    2016-01-01

    Electrochemical stability, moderate ionic conductivity and low electronic conductivity make the lithium phosphorous oxynitride (LiPON) electrolyte suitable for micro and nanoscale lithium batteries. The electrical and electrochemical properties of thin-film electrolytes can seriously compromise full battery performance. Here, radio-frequency (RF)-sputtered LiPON thin films were fabricated in nitrogen plasma under different working pressure conditions. With a slight decrease in ...

  20. A model for electrochemical insertion limited by a phase transition process - eilpt

    Directory of Open Access Journals (Sweden)

    Adhoum N.

    2003-01-01

    Full Text Available This paper deals with electrochemical insertion into a cathodic material. New results on modeling of the influence of a solid phase transformation on the shape of voltamograms are presented. The original experiments concern the insertion of sodium into carbon during the cathodic reduction of molten NaF at 1020 °C, but in the present manuscript emphasis on the theoretical aspects of the work is put. Phase transformations during electrochemical insertion are taken into account, with various values for parameters such as the thermodynamic biphase equilibrium potential, the compared diffusion and phase transformation kinetics, and the electrode thickness. The voltamograms calculated present very specific features; some of them have already been observed experimentally in literature.

  1. Electrochemical intercalation of lithium into polypyrrole/silver vanadium oxide composite used for lithium primary batteries

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong-Won; Popov, Branko N. [Center for Electrochemical Engineering, Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208 (United States)

    2006-10-20

    Hybrid composites of polypyrrole (PPy) and silver vanadium oxide (SVO) used for lithium primary batteries were chemically synthesized by an oxidative polymerization of pyrrole monomer on the SVO surface in an acidic medium. The composite electrode exhibited higher discharge capacity and better rate capability as compared with the pristine SVO electrode. The improvement in electrochemical performance of the composite electrode was due to PPy which accommodates lithium ions and also enhances the SVO utilization. Chronoamperometric and ac-impedance measurements indicated that lithium intercalation proceeds under the mixed control by interfacial charge transfer and diffusion. The enhanced SVO utilization in the composite electrode results from a facilitated kinetics of interfacial charge transfer in the presence of PPy. (author)

  2. Electrochemical intercalation of lithium into polypyrrole/silver vanadium oxide composite used for lithium primary batteries

    Science.gov (United States)

    Lee, Jong-Won; Popov, Branko N.

    Hybrid composites of polypyrrole (PPy) and silver vanadium oxide (SVO) used for lithium primary batteries were chemically synthesized by an oxidative polymerization of pyrrole monomer on the SVO surface in an acidic medium. The composite electrode exhibited higher discharge capacity and better rate capability as compared with the pristine SVO electrode. The improvement in electrochemical performance of the composite electrode was due to PPy which accommodates lithium ions and also enhances the SVO utilization. Chronoamperometric and ac-impedance measurements indicated that lithium intercalation proceeds under the mixed control by interfacial charge transfer and diffusion. The enhanced SVO utilization in the composite electrode results from a facilitated kinetics of interfacial charge transfer in the presence of PPy.

  3. Controllable synthesis of hollow bipyramid β-MnO(2) and its high electrochemical performance for lithium storage.

    Science.gov (United States)

    Chen, Wei-Min; Qie, Long; Shao, Qing-Guo; Yuan, Li-Xia; Zhang, Wu-Xing; Huang, Yun-Hui

    2012-06-27

    Three types of MnO2 nanostructures, viz., α-MnO2 nanotubes, hollow β-MnO2 bipyramids, and solid β-MnO2 bipyramids, have been synthesized via a simple template-free hydrothermal method. Cyclic voltammetry and galvanostatic charge/discharge measurements demonstrate that the hollow β-MnO2 bipyramids exhibit the highest specific capacity and the best cyclability; the capacity retains 213 mAh g(-1) at a current density of 100 mA g(-1) after 150 cycles. XRD patterns of the lithiated β-MnO2 electrodes clearly show the expansion of lattice volume caused by lithiation, but the structure keeps stable during lithium insertion/extraction process. We suggest that the excellent performance for β-MnO2 can be attributed to its unique electrochemical reaction, compact tunnel-structure and hollow architecture. The hollow architecture can accommodate the volume change during charge/discharge process and improve effective diffusion paths for both lithium ions and electrons.

  4. Effects of Capacity Ratios between Anode and Cathode on Electrochemical Properties for Lithium Polymer Batteries

    International Nuclear Information System (INIS)

    Kim, Cheon-Soo; Jeong, Kyung Min; Kim, Keon; Yi, Cheol-Woo

    2015-01-01

    The areal capacity ratio of negative to positive electrodes (N/P ratio) is the most important factor to design the lithium ion batteries with high performance in the consideration of balanced electrochemical reactions. In this study, the effect of N/P ratio (1.10, 1.20, and 1.30) on electrochemical properties has been investigated with a lithium polymer battery with PVdF-coated separator and 1.40 Ah of capacity. The N/P ratio is controlled by adjusting the anode thickness with a fixed anode density. The cell with an N/P ratio higher than 1.10 effectively suppresses the lithium plating at the 0.85C-rate charging at 25 °C and the cell with 1.20 of N/P ratio shows the enhanced cycle performance in comparison with other cells. Among the cells with differently designed N/P ratios, significant difference was not observed in the aging test with fully charged batteries at 25 and 45 °C. The effect of N/P ratio on electrochemical properties of lithium batteries can help to design the safe full cell without lithium plating

  5. Synthesis and Characterization of Silicon Nanoparticles Inserted into Graphene Sheets as High Performance Anode Material for Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Yong Chen

    2014-01-01

    Full Text Available Silicon nanoparticles have been successfully inserted into graphene sheets via a novel method combining freeze-drying and thermal reduction. The structure, electrochemical performance, and cycling stability of this anode material were characterized by SEM, X-ray diffraction (XRD, charge/discharge cycling, and cyclic voltammetry (CV. CV showed that the Si/graphene nanocomposite exhibits remarkably enhanced cycling performance and rate performance compared with bare Si nanoparticles for lithium ion batteries. XRD and SEM showed that silicon nanoparticles inserted into graphene sheets were homogeneous and had better layered structure than the bare silicon nanoparticles. Graphene sheets improved high rate discharge capacity and long cycle-life performance. The initial capacity of the Si nanoparticles/graphene keeps above 850 mAhg−1 after 100 cycles at a rate of 100 mAg−1. The excellent cycle performances are caused by the good structure of the composites, which ensured uniform electronic conducting sheet and intensified the cohesion force of binder and collector, respectively.

  6. Lattice vibrations of materials for lithium rechargeable batteries II. Lithium extraction-insertion in spinel structures

    International Nuclear Information System (INIS)

    Julien, C.M.; Camacho-Lopez, M.A.

    2004-01-01

    Lithiated spinel manganese oxides with various amounts of lithium have been prepared through solid-state reaction and electrochemical intercalation and deintercalation. Local structure of the samples are studied using Raman scattering and Fourier transform infrared spectroscopy. We report vibrational spectra of lithiated manganese oxides Li x Mn 2 O 4 as a function of lithium concentration in the range 0.1≤x≤2.0. Raman and Fourier transform infrared (FTIR) spectral results indicated multiple-phase reactions when the lithium content is modified in the spinel lattice. Lattice dynamics of lithiated spinel manganese oxides have been interpreted using either a classical factor-group analysis or a local environment model. The structural modifications have been studied on the basis of vibrations of LiO 4 tetrahedral and MnO 6 octahedral units when Li/Mn≤0.5, and LiO 4 , LiO 6 , and MnO 6 structural units when Li/Mn>0.5

  7. Electrochemical study of nanometric Si on carbon for lithium ion secondary batteries

    Energy Technology Data Exchange (ETDEWEB)

    Doh, Chil-Hoon; Lee, Jung-Hoon; Lee, Duck-Jun; Kim, Ju-Seok; Jin, Bong-Soo; Moon, Seong-In [Korea Electrotechnology Research Institute, Changwon 641-120 (Korea, Republic of); Hwang, Young-Ki [Kyungnam University, Masan 631-701 (Korea, Republic of); Park, Cheol-Wan, E-mail: chdoh@keri.re.k [Sodiff Advanced Materials Co. Ltd, Youngju 750-080 (Korea, Republic of)

    2010-05-01

    The electrochemical and thermochemical properties of a silicon-graphite composite anode for lithium ion batteries were evaluated. The electrochemical properties were varied by the condition of pretreatment. The electrochemical pretreatment of constant current (C/10) and constant potential for 24 h showed specific discharge and charge capacities of 941 and 781 mA h g{sup -1} to give a specific irreversible capacity of 161 mA h g{sup -1} and a coulombic efficiency of 83%. The initial cycle as the next cycle of pretreatment showed a specific charge capacity (Li desertion) of 698 mA h g{sup -1} and a coulombic efficiency of 95%. Coulombic efficiency at the fifth cycle was 97% to clear up almost all of the irreversible capacity. During the pretreatment cycle to the fourth cycle, the average specific charge capacity was 683 mA h g{sup -1} and the cumulative irreversible capacity was 264 mA h g{sup -1}. Exothermic heat values based on the specific capacity of the discharged (Li insertion) electrode of silicon-graphite composite for the temperature range of 50-300 {sup 0}C were 2.09 and 2.21 J mA{sup -1}h{sup -1} for 0 and 2 h as time of pretreatment in the case of just disassembled wet electrodes and 1.43 and 1.01 J mA{sup -1}h{sup -1} for 12 and 24 h as time of pretreatment in the case of dried electrodes, respectively.

  8. Solvents effects on electrochemical characteristics of graphite fluoride-lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Nobuatsu, W.; Hidekazu, T.; Rika, H.; Tsuyoshi, N.

    1982-11-01

    A study was made of the electrochemical characteristics of graphite fluoride-lithium batteries in various non-aqueous solvents. Two types of graphite fluorides (C/sub 2/F) /SUB n/ and (CF) /SUB n/ were used as cathode materials. The discharge characteristics of graphite fluorides were better in dimethylsulfoxide, ..gamma..-butyrolactone, propylene carbonate and sulfolane in that order. The relation between electrod potential of graphite fluoride and solvation energy of lithium ion with each solvent indicates that solvated lithium ion is intercalated into graphite fluoride layers by the electrode reaction. Both the difference in the overpotentials and in the rates of OCV recovery among these solvents further supports the proposed reaction mechanism.

  9. Electrochemical Model for Ionic Liquid Electrolytes in Lithium Batteries

    International Nuclear Information System (INIS)

    Yoo, Kisoo; Deshpande, Anirudh; Banerjee, Soumik; Dutta, Prashanta

    2015-01-01

    ABSTRACT: Room temperature ionic liquids are considered as potential electrolytes for high performance and safe lithium batteries due to their very low vapor pressure and relatively wide electrochemical and thermal stability windows. Unlike organic electrolytes, ionic liquid electrolytes are molten salts at room temperature with dissociated cations and anions. These dissociated ions interfere with the transport of lithium ions in lithium battery. In this study, a mathematical model is developed for transport of ionic components to study the performance of ionic liquid based lithium batteries. The mathematical model is based on a univalent ternary electrolyte frequently encountered in ionic liquid electrolytes of lithium batteries. Owing to the very high concentration of components in ionic liquid, the transport of lithium ions is described by the mutual diffusion phenomena using Maxwell-Stefan diffusivities, which are obtained from atomistic simulation. The model is employed to study a lithium-ion battery where the electrolyte comprises ionic liquid with mppy + (N-methyl-N-propyl pyrrolidinium) cation and TFSI − (bis trifluoromethanesulfonyl imide) anion. For a moderate value of reaction rate constant, the electric performance results predicted by the model are in good agreement with experimental data. We also studied the effect of porosity and thickness of separator on the performance of lithium-ion battery using this model. Numerical results indicate that low rate of lithium ion transport causes lithium depleted zone in the porous cathode regions as the porosity decreases or the length of the separator increases. The lithium depleted region is responsible for lower specific capacity in lithium-ion cells. The model presented in this study can be used for design of optimal ionic liquid electrolytes for lithium-ion and lithium-air batteries

  10. Layered lithium transition metal nitrides as novel anodes for lithium secondary batteries

    International Nuclear Information System (INIS)

    Liu Yu; Horikawa, Kumi; Fujiyosi, Minako; Imanishi, Nobuyuki; Hirano, Atsushi; Takeda, Yasuo

    2004-01-01

    We report the approach to overcome the deterrents of the hexagonal Li 2.6 Co 0.4 N as potential insertion anode for lithium ion batteries: the rapid capacity fading upon long cycles and the fully Li-rich state before cycling. Research reveals that the appropriate amount of Co substituted by Cu can greatly improve the cycling performance of Li 2.6 Co 0.4 N. It is attributed to the enhanced electrochemical stability and interfacial comparability. However, doped Cu leads to a slightly decreased capacity. High energy mechanical milling (HEMM) was found to effectively improve the reversible capacity associated with the electrochemical kinetics by modifying the active hosts' morphology characteristics. Moreover, the composite based on mesocarbon microbead (MCMB) and Li 2.6 Co 0.4 N was developed under HEMM. The composite demonstrates a high first cycle efficiency at 100% and a large reversible capacity of ca. 450 mAh g -1 , as well as a stable cycling performance. This work may contribute to a development of the lithium transition metal nitrides as novel anodes for lithium ion batteries

  11. The influence of the pyrolysis temperature on the electrochemical behavior of carbon-rich SiCN polymer-derived ceramics as anode materials in lithium-ion batteries

    Science.gov (United States)

    Reinold, Lukas Mirko; Yamada, Yuto; Graczyk-Zajac, Magdalena; Munakata, Hirokazu; Kanamura, Kiyoshi; Riedel, Ralf

    2015-05-01

    Within this study we report on the impact of the pyrolysis temperature on the structural and electrochemical properties of the poly(phenylvinylsilylcarbodiimide) derived silicon carbonitride (SiCN) ceramic. Materials pyrolysed at 800 °C and 1300 °C, SiCN 800 and SiCN 1300, are found amorphous. Raman spectroscopy measurements indicate the increase in ordering of the free carbon phase with increasing pyrolysis temperature which leads to lower capacity recovered by SiCN 1300. Significant hysteresis is found for materials pyrolysed at 800 °C during electrochemical lithium insertion/extraction. This feature is attributed to much higher hydrogen content in SiCN 800 sample. An aging of SiCN 800 reflected by a change of elemental composition upon contact to air and a strong film formation are attenuated at a higher pyrolysis temperature. Single particle microelectrode investigation on SiCN 800 and SiCN 1300 clarify different electrochemical behavior of the materials. Much lower charge transfer resistance of SiCN 1300 in comparison to SiCN 800 explains better high currents electrochemical performance. Lithium ions diffusion coefficient Dmin ranges from 3.2 10-9 cm2s-1 to 6.4 10-11 cm2s-1 and is independent on the potential.

  12. Electrochemical Evaluation of Corrosion Inhibiting Layers Formed in a Defect from Lithium-Leaching Organic Coatings

    NARCIS (Netherlands)

    Visser, P.; Meeusen, M.; Gonzalez Garcia, Y.; Terryn, H.A.; Mol, J.M.C.

    2017-01-01

    This work presents the electrochemical evaluation of protective layers generated in a coating defect from lithium-leaching organic coatings on AA2024-T3 aluminum alloys as a function of neutral salt spray exposure time. Electrochemical impedance spectroscopy was used to study the electrochemical

  13. Lithium intercalation into layered LiMnO2

    DEFF Research Database (Denmark)

    Vitins, G.; West, Keld

    1997-01-01

    Recently Armstrong and Bruce(1) reported a layered modification of lithium manganese oxide, LiMnO2, isostructural with LiCoO2. LiMnO2 obtained by ion exchange from alpha-NaMnO2 synthesized in air is characterized by x-ray diffraction and by electrochemical insertion and extraction of lithium...... in a series of voltage ranges between 1.5 and 4.5 V relative to a lithium electrode. During cycling voltage plateaus at 3.0 and 4.0 V vs. Li develop, indicating that the material is converted from its original layered structure to a spinel structure. This finding is confirmed by x-ray diffraction. Contrary...... to expectations based on thermodynamics, insertion of larger amounts of lithium leads to a more complete conversion. We suggest that a relatively high mobility of manganese leaves Li and Mn randomly distributed in the close-packed oxygen lattice after a deep discharge. This isotropic Mn distribution can...

  14. Lithium carbon batteries with solid polymer electrolyte; Accumulateur lithium carbone a electrolyte solide polymere

    Energy Technology Data Exchange (ETDEWEB)

    Andrieu, X.; Boudin, F. [Alcatel Alsthom Recherche, 91 - Marcoussis (France)

    1996-12-31

    The lithium carbon batteries studied in this paper use plasticized polymer electrolytes made with passive polymer matrix swollen by a liquid electrolyte with a high ionic conductivity (> 10{sup -3} S/cm at 25 deg. C). The polymers used to prepare the gels are polyacrylonitrile (PAN) and vinylidene poly-fluoride (PVdF). The electrochemical and physical properties of these materials are analyzed according to their composition. The behaviour of solid electrolytes with different materials of lithium ion insertion (graphite and LiNiO{sub 2}) are studied and compared to liquid electrolytes. The parameters taken into account are the reversible and irreversible capacities, the cycling performance and the admissible current densities. Finally, complete lithium ion batteries with gelled electrolytes were manufactured and tested. (J.S.) 2 refs.

  15. Lithium carbon batteries with solid polymer electrolyte; Accumulateur lithium carbone a electrolyte solide polymere

    Energy Technology Data Exchange (ETDEWEB)

    Andrieu, X; Boudin, F [Alcatel Alsthom Recherche, 91 - Marcoussis (France)

    1997-12-31

    The lithium carbon batteries studied in this paper use plasticized polymer electrolytes made with passive polymer matrix swollen by a liquid electrolyte with a high ionic conductivity (> 10{sup -3} S/cm at 25 deg. C). The polymers used to prepare the gels are polyacrylonitrile (PAN) and vinylidene poly-fluoride (PVdF). The electrochemical and physical properties of these materials are analyzed according to their composition. The behaviour of solid electrolytes with different materials of lithium ion insertion (graphite and LiNiO{sub 2}) are studied and compared to liquid electrolytes. The parameters taken into account are the reversible and irreversible capacities, the cycling performance and the admissible current densities. Finally, complete lithium ion batteries with gelled electrolytes were manufactured and tested. (J.S.) 2 refs.

  16. Coupled Mechanical-Electrochemical-Thermal Analysis of Failure Propagation in Lithium-ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chao; Santhanagopalan, Shriram; Pesaran, Ahmad

    2016-07-28

    This is a presentation given at the 12th World Congress for Computational Mechanics on coupled mechanical-electrochemical-thermal analysis of failure propagation in lithium-ion batteries for electric vehicles.

  17. Effect of calcium on the electrochemical behavior of lithium anode in LiOH aqueous solution used for lithium–water battery

    International Nuclear Information System (INIS)

    Zhang Ziyan; Chen Kanghua; Ni Erfu

    2012-01-01

    The effect of minor addition of calcium to lithium anode on the electrochemical behavior of lithium anode in 4 M LiOH at 30 °C temperature is investigated by hydrogen collection, polarization curves and electrochemical impedance spectroscopy. The results show that the hydrogen evolution rate is marginally reduced with increasing calcium content. Addition of calcium to lithium mainly inhibits the anodic process. Minor addition of calcium to lithium slightly reduced the discharge current of lithium anode. Minor addition of calcium to lithium anode marginally enhances the hydrogen inhibition of lithium by the formation of calcium hydride combined with LiOH and LiOH·H 2 O formed on the anode surface.

  18. Synthesis and Electrochemical Performance of a Lithium Titanium Phosphate Anode for Aqueous Lithium-Ion Batteries

    KAUST Repository

    Wessells, Colin

    2011-01-01

    Lithium-ion batteries that use aqueous electrolytes offer safety and cost advantages when compared to today\\'s commercial cells that use organic electrolytes. The equilibrium reaction potential of lithium titanium phosphate is -0.5 V with respect to the standard hydrogen electrode, which makes this material attractive for use as a negative electrode in aqueous electrolytes. This material was synthesized using a Pechini type method. Galvanostatic cycling of the resulting lithium titanium phosphate showed an initial discharge capacity of 115 mAh/g and quite good capacity retention during cycling, 84% after 100 cycles, and 70% after 160 cycles at a 1 C cycling rate in an organic electrolyte. An initial discharge capacity of 113 mAh/g and capacity retention of 89% after 100 cycles with a coulombic efficiency above 98% was observed at a C/5 rate in pH -neutral 2 M Li2 S O4. The good cycle life and high efficiency in an aqueous electrolyte demonstrate that lithium titanium phosphate is an excellent candidate negative electrode material for use in aqueous lithium-ion batteries. © 2011 The Electrochemical Society.

  19. Chemically Etched Silicon Nanowires as Anodes for Lithium-Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    West, Hannah Elise [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-08-01

    This study focused on silicon as a high capacity replacement anode for Lithium-ion batteries. The challenge of silicon is that it expands ~270% upon lithium insertion which causes particles of silicon to fracture, causing the capacity to fade rapidly. To account for this expansion chemically etched silicon nanowires from the University of Maine were studied as anodes. They were built into electrochemical half-cells and cycled continuously to measure the capacity and capacity fade.

  20. Dynamic Electrochemical Impedance Spectroscopy of a Three-Electrode Lithium-Ion Battery during Pulse Charge and Discharge

    International Nuclear Information System (INIS)

    Huang, Jun; Ge, Hao; Li, Zhe; Zhang, Jianbo

    2015-01-01

    Highlights: • Dynamic EIS is performed on a three-electrode pouch cell; • Charge transfer resistance during insertion is generally larger than that during deinsertion due to the surface concentration change; • An inductive behavior is revealed at low frequencies due to the violation of stationary condition in DEIS measurement; • Electrochemical models of a single active particle in both time and frequency domain are developed. • The model predicts a positive correlation between the lower frequency limit and the DC current. - Abstract: The dynamic electrochemical impedance spectroscopy (DEIS) of a three-electrode pouch type lithium-ion battery is measured using a series of sine wave perturbations super-imposed on pulse charge and discharge. The DEIS reveals noticeable differences between charge and discharge at frequencies corresponding to the charge transfer reaction. The charge transfer resistance during intercalation is generally found to be larger than that during deintercalation for the battery chemistry in this study. This result is mainly attributed to the decreased Li ion concentration in the electrolyte during intercalation. At low frequencies, an abnormal inductive behavior is also observed. Such abnormality is found to result from the violation of stationary condition, i.e. the state of the battery under pulse charge or discharge deviates significantly from its initial condition for the perturbation of low frequencies. To analytically define the stationary condition, we develop electrochemical models of a single active particle in both time and frequency domain, which describes the transport of lithium ions in both active particle and electrolyte phase and the interfacial charge transfer reactions at their interface. The lower frequency limit is a key parameter to ensure a quasistationary state during the DEIS measurement. An explicit formulation of the stationary condition predicts a positive correlation between the lower frequency limit and

  1. Optimization of reserve lithium thionyl chloride battery electrochemical design parameters

    Energy Technology Data Exchange (ETDEWEB)

    Doddapaneni, N.; Godshall, N.A.

    1987-01-01

    The performance of Reserve Lithium Thionyl Chloride (RLTC) batteries was optimized by conducting a parametric study of seven electrochemical parameters: electrode compression, carbon thickness, presence of catalyst, temperature, electrode limitation, discharge rate, and electrolyte acidity. Increasing electrode compression (from 0 to 15%) improved battery performance significantly (10% greater carbon capacity density). Although thinner carbon cathodes yielded less absolute capacity than did thicker cathodes, they did so with considerably higher volume efficiencies. The effect of these parameters, and their synergistic interactions, on electrochemical cell peformance is illustrated. 5 refs., 9 figs., 3 tabs.

  2. Optimization of reserve lithium thionyl chloride battery electrochemical design parameters

    Science.gov (United States)

    Doddapaneni, N.; Godshall, N. A.

    The performance of Reserve Lithium Thionyl Chloride (RLTC) batteries was optimized by conducting a parametric study of seven electrochemical parameters: electrode compression, carbon thickness, presence of catalyst, temperature, electrode limitation, discharge rate, and electrolyte acidity. Increasing electrode compression (from 0 to 15 percent) improved battery performance significantly (10 percent greater carbon capacity density). Although thinner carbon cathodes yielded less absolute capacity than did thicker cathodes, they did so with considerably higher volume efficiencies. The effect of these parameters, and their synergistic interactions, on electrochemical cell performance is illustrated.

  3. Simultaneously Coupled Mechanical-Electrochemical-Thermal Simulation of Lithium-Ion Cells: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chao; Santhanagopalan, Shriram; Sprague, Michael A.; Pesaran, Ahmad A.

    2016-08-01

    Understanding the combined electrochemical-thermal and mechanical response of a system has a variety of applications, for example, structural failure from electrochemical fatigue and the potential induced changes of material properties. For lithium-ion batteries, there is an added concern over the safety of the system in the event of mechanical failure of the cell components. In this work, we present a generic multi-scale simultaneously coupled mechanical-electrochemical-thermal model to examine the interaction between mechanical failure and electrochemical-thermal responses. We treat the battery cell as a homogeneous material while locally we explicitly solve for the mechanical response of individual components using a homogenization model and the electrochemical-thermal responses using an electrochemical model for the battery. A benchmark problem is established to demonstrate the proposed modeling framework. The model shows the capability to capture the gradual evolution of cell electrochemical-thermal responses, and predicts the variation of those responses under different short-circuit conditions.

  4. An Electrochemical Impedance Spectroscopy Study on a Lithium Sulfur Pouch Cell

    DEFF Research Database (Denmark)

    Stroe, Daniel Loan; Knap, Vaclav; Swierczynski, Maciej Jozef

    2016-01-01

    The impedance behavior of a 3.4 Ah pouch Lithium-Sulfur cell was extensively characterized using the electrochemical impedance spectroscopy (EIS) technique. EIS measurements were performed at various temperatures and over the entire state-of-charge (SOC) interval without applying a superimposed DC...

  5. Electrochemical performances of lithium ion battery using alkoxides of group 13 as electrolyte solvent

    International Nuclear Information System (INIS)

    Kaneko, Fuminari; Masuda, Yuki; Nakayama, Masanobu; Wakihara, Masataka

    2007-01-01

    Tris(methoxy polyethylenglycol) borate ester (B-PEG) and aluminum tris(polyethylenglycoxide) (Al-PEG) were used as electrolyte solvent for lithium ion battery, and the electrochemical property of these electrolytes were investigated. These electrolytes, especially B-PEG, showed poor electrochemical stability, leading to insufficient discharge capacity and rapid degradation with cycling. These observations would be ascribed to the decomposition of electrolyte, causing formation of unstable passive layer on the surface of electrode in lithium ion battery at high voltage. However, significant improvement was observed by the addition of aluminum phosphate (AlPO 4 ) powder into electrolyte solvent. AC impedance technique revealed that the increase of interfacial resistance of electrode/electrolyte during cycling was suppressed by adding AlPO 4 , and this suppression could enhance the cell capabilities. We infer that dissolved AlPO 4 components formed electrochemically stable layer on the surface of electrode

  6. Structure dependent electrochemical performance of Li-rich layered oxides in lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Fang; Yao, Yuze; Wang, Haiyan; Xu, Gui-Liang; Amine, Khalil; Sun, Shi-Gang; Shao, Minhua

    2017-04-08

    Rational and precise control of the structure and dimension of electrode materials is an efficient way to improve their electrochemical performance. In this work, solvothermal or co-precipitation method is used to synthesize lithium-rich layered oxide materials of Li1.2Mn0.56Co0.12Ni0.12O2 (LLO) with various morphologies and structures, including microspheres, microrods, nanoplates, and irregular nanoparticles. These materials exhibit strong structure- dependent electrochemical properties. The porous hierarchical structured LLO microrods exhibit the best performance, delivering a discharge capacity of 264.6 mAh g(-1) at 0.5 C with over 91% retention after 100 cycles. At a high rate of 5 C, a high discharge capacity of 173.6 mAh g(-1) can be achieved. This work reveals the relationship between the morphologies and electrochemical properties of LLO cathode materials, and provides a feasible approach to fabricating robust and high-performance electrode materials for lithium-ion batteries.

  7. Lithium storage properties of multiwall carbon nanotubes prepared by CVD

    International Nuclear Information System (INIS)

    Ahn, J.-O.; Andong National University,; Wang, G.X.; Liu, H.K.; Dou, S.X.

    2003-01-01

    Full text: Multiwall carbon nanotubes (MWCNTs) were synthesised by chemical vapour deposition (CVD) method using acetylene gas. The XRD pattern of as prepared carbon nanotubes showed that the d 002 value is 3.44 Angstroms. The morphology and microstructure of carbon nanotubes were characterized by HRTEM. Most of carbon nanotubes are entangled together to form bundles or ropes. The diameter of the carbon nanotubes is in the range of 10 ∼ 20 nm. There is a small amount of amorphous carbon particles presented in the sample. However, the yield of carbon nanotubes is more than 95%. Electrochemical properties of carbon nanotubes were characterised via a variety of electrochemical testing techniques. The result of CV test showed that the Li insertion potential is quite low, which is very close to O V versus Li + /Li reference electrode, whereas the potential for Li de-intercalation is in the range of 0.2-0.4 V. There exists a slight voltage hysteresis between Li intercalation and Li de-intercalation, which is similar to the other carbonaceous materials. The intensity of redox peaks of carbon nanotubes decrease with scanning cycle, indicating that the reversible Li insertion capacity gradually decreases. The carbon nanotubes electrode demonstrated a reversible lithium storage capacity of 340 mAh/g with good cyclability at moderate current density. Further improvement of Li storage capacity is possible by opening the end of carbon nanotubes to allow lithium insertion into inner graphene sheet of carbon nanotubes. The kinetic properties of lithium insertion in carbon nanotube electrodes were characterised by a.c. impedance measurements. It was found that the lithium diffusion coefficient d Li decreases with an increase of Li ion concentration in carbon nanotube host

  8. Lithium alloys and metal oxides as high-capacity anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Liang, Chu; Gao, Mingxia; Pan, Hongge; Liu, Yongfeng; Yan, Mi

    2013-01-01

    Highlights: •Progress in lithium alloys and metal oxides as anode materials for lithium-ion batteries is reviewed. •Electrochemical characteristics and lithium storage mechanisms of lithium alloys and metal oxides are summarized. •Strategies for improving electrochemical lithium storage properties of lithium alloys and metal oxides are discussed. •Challenges in developing lithium alloys and metal oxides as commercial anodes for lithium-ion batteries are pointed out. -- Abstract: Lithium alloys and metal oxides have been widely recognized as the next-generation anode materials for lithium-ion batteries with high energy density and high power density. A variety of lithium alloys and metal oxides have been explored as alternatives to the commercial carbonaceous anodes. The electrochemical characteristics of silicon, tin, tin oxide, iron oxides, cobalt oxides, copper oxides, and so on are systematically summarized. In this review, it is not the scope to retrace the overall studies, but rather to highlight the electrochemical performances, the lithium storage mechanism and the strategies in improving the electrochemical properties of lithium alloys and metal oxides. The challenges and new directions in developing lithium alloys and metal oxides as commercial anodes for the next-generation lithium-ion batteries are also discussed

  9. Semi-empirical master curve concept describing the rate capability of lithium insertion electrodes

    Science.gov (United States)

    Heubner, C.; Seeba, J.; Liebmann, T.; Nickol, A.; Börner, S.; Fritsch, M.; Nikolowski, K.; Wolter, M.; Schneider, M.; Michaelis, A.

    2018-03-01

    A simple semi-empirical master curve concept, describing the rate capability of porous insertion electrodes for lithium-ion batteries, is proposed. The model is based on the evaluation of the time constants of lithium diffusion in the liquid electrolyte and the solid active material. This theoretical approach is successfully verified by comprehensive experimental investigations of the rate capability of a large number of porous insertion electrodes with various active materials and design parameters. It turns out, that the rate capability of all investigated electrodes follows a simple master curve governed by the time constant of the rate limiting process. We demonstrate that the master curve concept can be used to determine optimum design criteria meeting specific requirements in terms of maximum gravimetric capacity for a desired rate capability. The model further reveals practical limits of the electrode design, attesting the empirically well-known and inevitable tradeoff between energy and power density.

  10. Chemical, structural, and electrochemical characterization of 5 V spinel and complex layered oxide cathodes of lithium ion batteries

    Science.gov (United States)

    Tiruvannamalai Annamalai, Arun Kumar

    2007-12-01

    proton insertion and oxygen loss at deep lithium extraction due to the chemical instability arising from a overlap of the Co3+/4+:3d band on the top of the O2-:2p band. The irreversible oxygen loss during the first charge and the consequent reversible capacities of the solid solutions between Li[Li1/3Mn 2/3]O2 and Li[Co1-yNiy]O2 has been found to be determined by the amount of lithium in the transition metal layer of the O3 type layered structure. The lithium content in the transition metal layer is, however, sensitively influenced by the tendency of Ni 3+ to get reduced to Ni2+ and the consequent volatilization of lithium during synthesis. Moreover, high Mn4+ content causes a decrease in oxygen mobility and loss. In addition, the chemically delithiated samples were found to adopt either the parent O3 type structure or the new P3 or O1 type structures depending upon the composition and synthesis temperature of the parent samples and the proton content inserted into the delithiated sample. In essence, the chemical and structural stabilities and the electrochemical performance factors of the layered (1-z) Li[Li1/3 Mn2/3]O2 · (z) Li[Co1-yNi y]O2 solid solution cathodes are found to be maximized by optimizing the contents of the various ions.

  11. Novel lithium titanate-graphene hybrid containing two graphene conductive frameworks for lithium-ion battery with excellent electrochemical performance

    Energy Technology Data Exchange (ETDEWEB)

    Ruiyi, Li; Tengyuan, Chen; Beibei, Sun [School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122 (China); Zaijun, Li [School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122 (China); Key Laboratory of Food Colloids and Biotechnology, Ministry of Education, Wuxi 214122 (China); Zhiquo, Gu; Guangli, Wang; Junkang, Liu [School of Chemical and Material Engineering, Jiangnan University, Wuxi 214122 (China)

    2015-10-15

    Graphical abstract: We developed a new Novel lithium titanate-graphene nanohybrid containing two graphene conductive frameworks. The unique architecture creates fast electron transfer and rapid mass transport of electrolyte. The hybrid electrode provides excellent electrochemical performances for lithium-ion batteries, including high specific capacity, outstanding rate capability and intriguing cycling stability. - Highlights: • We reported a new LTO-graphene nanohybrid containing two graphene conductive frameworks. • One graphene framework greatly improves the electrical conductivity of LTO crystal. • Another graphene framework enhances electrical conductivity of between LTO crystals and electrolyte transport. • The unique architecture creates big tap density, ultrafast electron transfer and rapid mass transport. • The hybrid electrode provides excellent electrochemical performance for lithium-ion batteries. - ABSTRACT: The paper reported the synthesis of lithium titanate(LTO)-graphene hybrid containing two graphene conductive frameworks (G@LTO@G). Tetrabutyl titanate and graphene were dispersed in tertbutanol and heated to reflux state by microwave irradiation. Followed by adding lithium acetate to produce LTO precursor/graphene (p-LTO/G). The resulting p-LTO/G offers homogeneous morphology and ultra small size. All graphene sheets were buried in the spherical agglomerates composed of primitive particles through the second agglomeration. The p-LTO/G was calcined to LTO@graphene (LTO@G). To obtain G@LTO@G, the LTO@G was further hybridized with graphene. The as-prepared G@LTO@G shows well-defined three-dimensional structure and hierarchical porous distribution. Its unique architecture creates big tap density, fast electron transfer and rapid electrolyte transport. As a result, the G@LTO@G provides high specific capacity (175.2 mA h g{sup −1} and 293.5 mA cm{sup −3}), outstanding rate capability (155.7 mAh g{sup −1} at 10C) and intriguing cycling

  12. Electrochemical Activity of Hydrothermally Synthesized Li-Ti-O Cubic Oxides towards Li Insertion

    Czech Academy of Sciences Publication Activity Database

    Fattakhova, Dina; Krtil, Petr

    2002-01-01

    Roč. 149, č. 9 (2002), s. 1224-1229 ISSN 0013-4651 R&D Projects: GA ČR GA203/99/0879 Institutional research plan: CEZ:AV0Z4040901 Keywords : lithium insertion * anatase electrodes * metal-oxides Subject RIV: CG - Electrochemistry Impact factor: 2.330, year: 2002

  13. Cathodes for lithium ion batteries: the benefits of using nanostructured materials

    International Nuclear Information System (INIS)

    Bazito, Fernanda F.C.; Torresi, Roberto M.

    2006-01-01

    Commercially available lithium ion cells, which are the most advanced among rechargeable batteries available so far, employ microcrystalline transition metal oxides as cathodes, which function as Li insertion hosts. In search for better electrochemical performance the use of nanomaterials in place of these conventional ones has emerged as excellent alternative. In this review we present a brief introduction about the motivations to use nanostructured materials as cathodes in lithium ion batteries. To illustrate such advantages we present some examples of research directed toward preparations and electrochemical data of the most used cathodes in nanoscale, such as LiCoO 2 , LiMn 2 O 4 , LiMnO 2 , LiV 2 O 5 e LiFePO 4 . (author)

  14. Electrochemical Modeling and Performance of a Lithium- and Manganese-Rich Layered Transition-Metal Oxide Positive Electrode

    Energy Technology Data Exchange (ETDEWEB)

    Dees, Dennis W.; Abraham, Daniel P; Lu, Wenquan; Gallagher, Kevin G.; Bettge, Martin; Jansen, Andrew N

    2015-01-21

    The impedance of a lithium- and manganese-rich layered transition-metal oxide (MR-NMC) positive electrode, specifically Li1.2Ni0.15Mn0.55Co0.1O2, is compared to two other transition-metal layered oxide materials, specifically LiNi0.8Co0.15Al0.05O2 (NCA) and Li1.05(Ni1/3Co1/3Mn1/3)0.95O2 (NMC). A more detailed electrochemical impedance spectroscopy (EIS) study is conducted on the LMR-NMC electrode, which includes a range of states-of-charge (SOCs) for both current directions (i.e. charge and discharge) and two relaxation times (i.e. hours and one hundred hours) before the EIS sweep. The LMR-NMC electrode EIS studies are supported by half-cell constant current and galvanostatic intermittent titration technique (GITT) studies. Two types of electrochemical models are utilized to examine the results. The first type is a lithium ion cell electrochemical model for intercalation active material electrodes that includes a complex active material/electrolyte interfacial structure. In conclusion, the other is a lithium ion half-cell electrochemical model that focuses on the unique composite structure of the bulk LMR-NMC materials.

  15. Morphological, structural and electrochemical properties of lithium iron phosphates synthesized by Spray Pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, L.S. [Universidad Carlos III de Madrid and IAAB, Avda. de la Universidad, 30, 28911 Leganes, Madrid (Spain); Meatza, I. de [Dpto. Energia, CIDETEC, Po Miramon 196, Parque Tecnologico de San Sebastian, 20009 Donostia-San Sebastian (Spain); Martin, M.I., E-mail: imartin@ietcc.csic.e [Universidad Carlos III de Madrid and IAAB, Avda. de la Universidad, 30, 28911 Leganes, Madrid (Spain); Bengoechea, M. [Dpto. Energia, CIDETEC, Po Miramon 196, Parque Tecnologico de San Sebastian, 20009 Donostia-San Sebastian (Spain); Cantero, I. [Dpto. I-D-i Nuevas Tecnologias, CEGASA, Artapadura, 11, 01013 Vitoria-Gasteiz (Spain); Rabanal, M.E., E-mail: mariaeugenia.rabanal@uc3m.e [Universidad Carlos III de Madrid and IAAB, Avda. de la Universidad, 30, 28911 Leganes, Madrid (Spain)

    2010-03-01

    In the field of materials for lithium ion batteries, the lithium iron phosphate LiFePO{sub 4} has been proven for use as a positive electrode due to its good resistance to thermal degradation and overcharge, safety and low cost. The use of nanostructured materials would improve its efficiency. This work shows the results of the synthesis of nanostructured materials with functional properties for lithium batteries through aerosol techniques. The Spray Pyrolysis method allows synthesizing nanostructured particles with spherical geometry, not agglomerates, with narrow distribution of particle size and homogeneous composition in respect to a precursor solution. Experimental techniques were focused on the morphological (SEM and TEM), structural (XRD and HRTEM-SAED), chemical (EDS) and electrochemical characterization.

  16. Morphological, structural and electrochemical properties of lithium iron phosphates synthesized by Spray Pyrolysis

    International Nuclear Information System (INIS)

    Gomez, L.S.; Meatza, I. de; Martin, M.I.; Bengoechea, M.; Cantero, I.; Rabanal, M.E.

    2010-01-01

    In the field of materials for lithium ion batteries, the lithium iron phosphate LiFePO 4 has been proven for use as a positive electrode due to its good resistance to thermal degradation and overcharge, safety and low cost. The use of nanostructured materials would improve its efficiency. This work shows the results of the synthesis of nanostructured materials with functional properties for lithium batteries through aerosol techniques. The Spray Pyrolysis method allows synthesizing nanostructured particles with spherical geometry, not agglomerates, with narrow distribution of particle size and homogeneous composition in respect to a precursor solution. Experimental techniques were focused on the morphological (SEM and TEM), structural (XRD and HRTEM-SAED), chemical (EDS) and electrochemical characterization.

  17. Type I Clathrates as Novel Silicon Anodes: An Electrochemical and Structural Investigation

    OpenAIRE

    Li, Ying; Raghavan, Rahul; Wagner, Nicholas A.; Davidowski, Stephen K.; Baggetto, Lo?c; Zhao, Ran; Cheng, Qian; Yarger, Jeffery L.; Veith, Gabriel M.; Ellis?Terrell, Carol; Miller, Michael A.; Chan, Kwai S.; Chan, Candace K.

    2015-01-01

    Silicon clathrates contain cage?like structures that can encapsulate various guest atoms or molecules. An electrochemical evaluation of type I silicon clathrates based on Ba8Al y Si46?y as the anode material for lithium?ion batteries is presented here. Postcycling characterization with nuclear magnetic resonance and X?ray diffraction shows no discernible structural or volume changes even after electrochemical insertion of 44 Li (?1 Li/Si) into the clathrate structure. The observed properties ...

  18. Role of nanorods insertion layer in ZnO-based electrochemical metallization memory cell

    Science.gov (United States)

    Mangasa Simanjuntak, Firman; Singh, Pragya; Chandrasekaran, Sridhar; Juanda Lumbantoruan, Franky; Yang, Chih-Chieh; Huang, Chu-Jie; Lin, Chun-Chieh; Tseng, Tseung-Yuen

    2017-12-01

    An engineering nanorod array in a ZnO-based electrochemical metallization device for nonvolatile memory applications was investigated. A hydrothermally synthesized nanorod layer was inserted into a Cu/ZnO/ITO device structure. Another device was fabricated without nanorods for comparison, and this device demonstrated a diode-like behavior with no switching behavior at a low current compliance (CC). The switching became clear only when the CC was increased to 75 mA. The insertion of a nanorods layer induced switching characteristics at a low operation current and improve the endurance and retention performances. The morphology of the nanorods may control the switching characteristics. A forming-free electrochemical metallization memory device having long switching cycles (>104 cycles) with a sufficient memory window (103 times) for data storage application, good switching stability and sufficient retention was successfully fabricated by adjusting the morphology and defect concentration of the inserted nanorod layer. The nanorod layer not only contributed to inducing resistive switching characteristics but also acted as both a switching layer and a cation diffusion control layer.

  19. Spectroscopic and Electrochemical Properties of Lithium-Rich LiFePO4 Cathode Synthesized by Solid-State Reaction

    Science.gov (United States)

    Rosaiah, P.; Hussain, O. M.; Zhu, Jinghui; Qiu, Yejun

    2017-08-01

    Lithium iron phosphate (Li x FePO4) is synthesized by a solid-state reaction method. The structural, electrical and electrochemical properties are studied in detail. It is found that the increment of lithium concentration (up to x = 1.05) does not affect the structure of LiFePO4 but improves its electrical conductivity as well as electrochemical performance. Surface morphological studies exhibited the formation of rod-like nanoparticles with small size. Electric and dielectric properties are also investigated over a frequency range of 1 Hz-1 MHz at different temperatures. The conductivity increased with increasing temperature, which follows the Arrhenius relation with the activation energy of about 0.31 eV. And the electrochemical tests found that the Li1.05FePO4 cathode possessed improved discharge capacity with better cycling performance.

  20. Structural and Electrochemical Evaluation of Three- and Two-Dimensional Organohalide Perovskites and Their Influence on the Reversibility of Lithium Intercalation.

    Science.gov (United States)

    Ramirez, Daniel; Suto, Yusaku; Rosero-Navarro, Nataly Carolina; Miura, Akira; Tadanaga, Kiyoharu; Jaramillo, Franklin

    2018-04-02

    Organic-inorganic hybrid perovskite materials have recently been investigated in a variety of applications, including solar cells, light emitting devices (LEDs), and lasers because of their impressive semiconductor properties. Nevertheless, the perovskite structure has the ability to host extrinsic elements, making its application in the battery field possible. During the present study, we fabricated and investigated the electrochemical properties of three-dimensional (3D) methylammonium lead mixed-halide CH 3 NH 3 PbI 3- x Br x and two-dimensional (2D) propylammonium-methlylammonium lead bromide (CH 3 NH 3 ) 2 (CH 3 (CH 2 ) 2 NH 3 ) 2 Pb 3 Br 10 hybrid perovskite thin films as electrode materials for Li-ion batteries. These electrodes were obtained by solution processing at 100 °C. CH 3 NH 3 PbBr 3 achieved high discharge/charge capacities of ∼500 mA h g -1 /160 mA h g -1 that could account also for other processes taking place during the Li intercalation. It was also found that bromine plays an important role for lithium intercalation, while the new 2D (CH 3 NH 3 ) 2 (CH 3 (CH 2 ) 2 NH 3 ) 2 Pb 3 Br 10 with a layered structure allowed reversibility of the lithium insertion-extraction of 100% with capacities of ∼375 mA h g -1 in the form of a thin film. Results suggest that tuning the composition of these materials can be used to improve intercalation capacities, while modification from 3D to 2D layered structures contributes to improving lithium extraction. The mechanism of the lithium insertion-extraction may consist of an intercalation mechanism in the hybrid material accompanying the alloying-dealloying process of the Li x Pb intermetallic compounds. This work contributes to revealing the relevance of both composition and structure of potential hybrid perovskite materials as future thin film electrode materials with high capacity and compositional versatility.

  1. Comparative ion insertion study into a nanostructured vanadium oxide in aqueous salt solutions

    Energy Technology Data Exchange (ETDEWEB)

    Yuan, Q.; Ren, S. L.; Zukowski, J.; Pomeroy, M.; Soghomonian, V., E-mail: soghomon@vt.edu [Department of Physics, Virginia Tech, Blacksburg, Virginia 24061 (United States)

    2014-07-07

    We present a comparative study for the electrochemical insertion of different cations into a nanostructured vanadium oxide material. The oxide is hydrothemally synthesized and electrically characterized by variable temperature measurements. The electrochemical reactions are performed in aqueous chloride solutions of lithium, sodium, potassium, and ammonium, and the electrochemical behavior of various cycles are correlated with visual changes in the vanadium oxide nanosheets as observed by scanning electron microscopy. We note an increase in the specific charge per cycle in the cases of sodium and ammonium ions only, correlated with minimal physical changes to the nanosheets. The differing behavior of the various ions has implications for their use in electrical energy storage applications.

  2. Lithium-Ion Battery Power Degradation Modelling by Electrochemical Impedance Spectroscopy

    DEFF Research Database (Denmark)

    Stroe, Daniel-Ioan; Swierczynski, Maciej Jozef; Stroe, Ana-Irina

    2017-01-01

    This paper investigates the use of the electrochemical impedance spectroscopy (EIS) technique as an alternative to the DC pulses technique for estimating the power capability decrease of Lithium-ion batteries during calendar ageing. Based on results obtained from calendar ageing tests performed...... at different conditions during one to two years, a generalized model that estimates the battery power capability decrease as function of the resistance Rs increase (obtained from EIS) was proposed and successfully verified....

  3. Study of lithium insertion in hard carbon made from cotton wool

    Science.gov (United States)

    Peled, Emanuel; Eshkenazi, Victor; Rosenberg, Yuri

    Hard-carbon materials were made either by one-step or multi-step pyrolysis of cotton cloth between 700 and 1100°C. All carbons have been characterized by gas sorption, X-ray diffraction (XRD) and small-angle X-ray scattering (SAXS) techniques. Two types of carbons have been obtained. One, made by multi-step pyrolysis, has the highest lithium reversible capacity [about 600 (mA h)/g] and two distinct voltage regions: a sloping one between 1.5 and about 0.1 V, called the high-voltage region (HVR), and a horizontal one between 0.1 and 0 V, called the low-voltage plateau (LVP). The other carbons made by the one-step process have only the HVR and less capacity [up to 470 (mA h)/g]. The influence of the current density and temperature on the capacity and degradation rate in both LVP and HVR was checked. We suggest that there are two different modes of lithium insertion: intercalation-like (on both sides of single graphene sheets) at lower potentials and chemical binding to edge carbon atoms at higher potentials vs. lithium reference electrode. A schematic model for lithiated carbon is proposed.

  4. Re-entrant lithium local environments and defect driven electrochemistry of Li- and Mn-rich Li-ion battery cathodes.

    Science.gov (United States)

    Dogan, Fulya; Long, Brandon R; Croy, Jason R; Gallagher, Kevin G; Iddir, Hakim; Russell, John T; Balasubramanian, Mahalingam; Key, Baris

    2015-02-18

    Direct observations of structure-electrochemical activity relationships continue to be a key challenge in secondary battery research. (6)Li magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy is the only structural probe currently available that can quantitatively characterize local lithium environments on the subnanometer scale that dominates the free energy for site occupation in lithium-ion (Li-ion) intercalation materials. In the present study, we use this local probe to gain new insights into the complex electrochemical behavior of activated 0.5(6)Li2MnO3·0.5(6)LiMn(0.5)Ni(0.5)O2, lithium- and manganese-rich transition-metal (TM) oxide intercalation electrodes. We show direct evidence of path-dependent lithium site occupation, correlated to structural reorganization of the metal oxide and the electrochemical hysteresis, during lithium insertion and extraction. We report new (6)Li resonances centered at ∼1600 ppm that are assigned to LiMn6-TM(tet) sites, specifically, a hyperfine shift related to a small fraction of re-entrant tetrahedral TMs (Mn(tet)), located above or below lithium layers, coordinated to LiMn6 units. The intensity of the TM layer lithium sites correlated with tetrahedral TMs loses intensity after cycling, indicating limited reversibility of TM migrations upon cycling. These findings reveal that defect sites, even in dilute concentrations, can have a profound effect on the overall electrochemical behavior.

  5. Diagnosis of Lithium-Ion Batteries State-of-Health based on Electrochemical Impedance Spectroscopy Technique

    DEFF Research Database (Denmark)

    Stroe, Daniel Ioan; Swierczynski, Maciej Jozef; Stan, Ana-Irina

    2014-01-01

    Lithium-ion batteries have developed into a popular energy storage choice for a wide range of applications because of their superior characteristics in comparison to other energy storage technologies. Besides modelling the performance behavior of Lithium-ion batteries, it has become of huge...... interest to accurately diagnose their state-of-health (SOH). At present, Lithium-ion batteries are diagnosed by performing capacity or resistance (current pulse) measurements; however, in the majority of the cases, these measurements are time consuming and result in changing the state of the battery...... as well. This paper investigates the use of the electrochemical impedance spectroscopy (EIS) technique for SOH diagnosis of Lithium-ion battery cells, instead of using the aforementioned techniques, since this new method allows for online and direct measurement of the battery cell response in any working...

  6. V2O5 xerogel-poly(ethylene oxide) hybrid material: Synthesis, characterization, and electrochemical properties

    International Nuclear Information System (INIS)

    Guerra, Elidia M.; Ciuffi, Katia J.; Oliveira, Herenilton P.

    2006-01-01

    In this work, we report the synthesis, characterization, and electrochemical properties of vanadium pentoxide xerogel-poly(ethylene oxide) (PEO) hybrid materials obtained by varying the average molecular weight of the organic component as well as the components' ratios. The materials were characterized by X-ray diffraction, ultraviolet/visible and infrared spectroscopies, thermogravimetric analysis, scanning electron microscopy, electron paramagnetic resonance, and cyclic voltammetry. Despite the presence of broad and low intensity peaks, the X-ray diffractograms indicate that the lamellar structure of the vanadium pentoxide xerogel is preserved, with increase in the interplanar spacing, giving evidence of a low-crystalline structure. We found that the electrochemical behaviour of the hybrid materials is quite similar to that found for the V 2 O 5 xerogel alone, and we verified that PEO leads to stabilization and reproducibility of the Li + electrochemical insertion/de-insertion into the V 2 O 5 xerogel structure, which makes these materials potential components of lithium ion batteries. - Graphical abstract: The synthesis, structural and electrochemical properties of vanadium pentoxide xerogel-poly(ethylene oxide) hybrid materials have been described. Despite the presence of broad and low intensity peaks, the X-ray diffractograms indicate that the lamellar structure of the vanadium pentoxide xerogel is preserved. The cyclic voltammetry technique demonstrated that PEO intercalation provides an improvement in the electrochemical properties, mainly with respect to the lithium electroinsertion process into the oxide matrix

  7. Synthesis of hollandite-type LixMnO2 by Li+ ion-exchange in molten salt and lithium insertion characteristics

    International Nuclear Information System (INIS)

    Kadoma, Yoshihiro; Oshitari, Satoru; Ui, Koichi; Kumagai, Naoaki

    2007-01-01

    The Li + ion-exchange reaction of K + -type α-K 0.14 MnO 1.93 .nH 2 O containing different amounts of water molecules (n = 0-0.15) with a large (2 x 2) tunnel structure has been investigated in a LiNO 3 -LiCl molten salt at 300 deg. C. The Li + ion-exchanged products were examined by chemical analysis, X-ray diffraction, and transmission electron microscopy measurements. The K + ions and the hydrogens of the water molecules in the (2 x 2) tunnels of α-MnO 2 were exchanged by Li + ions in the molten salt, resulting in the Li + -type α-MnO 2 containing different amounts of Li + ions and lithium oxide (Li 2 O) in the (2 x 2) tunnels with maintaining the original hollandite structure. The electrochemical properties and structural variation with initial discharge and charge-discharge cycling of the Li + ion-exchanged α-MnO 2 samples have been investigated as insertion compounds in the search for new cathode materials for rechargeable lithium batteries. The Li + ion-exchanged α-MnO 2 samples provided higher capacities and higher Li + ion diffusivity than the parent K + -type materials on initial discharge and charge-discharge cyclings, probably due to the structural stabilization with the existence of Li 2 O in the (2 x 2) tunnels

  8. Preparation of the electrochemically formed spinel-lithium manganese oxides

    Energy Technology Data Exchange (ETDEWEB)

    Katakura, Katsumi; Wada, Kohei; Kajiki, Yoshiyuki; Yamamoto, Akiko [Department of Chemical Engineering, Nara National College of Technology, 22 Yata-cho Yamotokoriyama, Nara 639-1080 (Japan); Ogumi, Zempachi [Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510 (Japan)

    2009-04-01

    Electrochemically formed spinel-lithium manganese oxides were synthesized from manganese hydroxides prepared by a cathodic electrochemical precipitation from various concentrations of manganese nitrate solutions. Two types of manganese hydroxides were formed from diluted and concentrated Mn(NO{sub 3}){sub 2} aqueous solutions. Uniform and equi-sized disk shaped Mn(OH){sub 2} crystals of 0.2-5 {mu}m in diameter were obtained on a Pt substrate after the electrochemical precipitation from lower concentration of ranging from 2 mmol dm{sup -3} to 2 mol dm{sup -3} Mn(NO{sub 3}){sub 2} aq., while the grass blade-like precipitate which is ascribed to manganese hydroxide with 20-80 {mu}m long and 1-5 {mu}m wide were formed from concentrated Mn(NO{sub 3}){sub 2} aq. Both manganese hydroxides gave the electrochemically formed spinel-LiMn{sub 2}O{sub 4} onto a Pt sheet, which is ready for electrochemical measurement, after calcination of the Li incorporated precipitate at 750 C without any additives. While the shape and size of the secondary particle frameworks (aggregates) of the electrochemically formed spinel-LiMn{sub 2}O{sub 4} can be controlled by the electrolysis conditions, the nanostructured primary crystals of 200 nm in diameter were obtained in all cases except that the fiber-like nanostructured spinel-LiMn{sub 2}O{sub 4} crystals with 200 nm in diameter were obtained from concentrated Mn(NO{sub 3}){sub 2} aq. Though these two types of electrochemically formed spinel-LiMn{sub 2}O{sub 4} showed well-shaped CVs even in higher scan rates, it would be suitable for high power density battery applications. These behaviors are assumed to be ascribed to the crystal size and shape of the processed spinel-LiMn{sub 2}O{sub 4}. (author)

  9. Organic solvents, electrolytes, and lithium ion cells with good low temperature performance

    Science.gov (United States)

    Smart, Marshall C. (Inventor); Bugga, Ratnakumar V. (Inventor); Surampudi, Subbarao (Inventor); Huang, Chen-Kuo (Inventor)

    2002-01-01

    Multi-component organic solvent systems, electrolytes and electrochemical cells characterized by good low temperature performance are provided. In one embodiment, an improved organic solvent system contains a ternary mixture of ethylene carbonate, dimethyl carbonate and diethyl carbonate. In other embodiments, quaternary systems include a fourth component, i.e, an aliphatic ester, an asymmetric alkyl carbonate or a compound of the formula LiOX, where X is R, COOR, or COR, where R is alkyl or fluoroalkyl. Electrolytes based on such organic solvent systems are also provided and contain therein a lithium salt of high ionic mobility, such as LiPF.sub.6. Reversible electrochemical cells, particularly lithium ion cells, are constructed with the improved electrolytes, and preferably include a carbonaceous anode, an insertion type cathode, and an electrolyte interspersed therebetween.

  10. Graphene-based Electrochemical Energy Conversion and Storage: Fuel cells, Supercapacitors and Lithium Ion Batteries

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Junbo; Shao, Yuyan; Ellis, Michael A.; Moore, Robert; Yi, Baolian

    2011-09-14

    Graphene has attracted extensive research interest due to its strictly 2-dimensional (2D) structure, which results in its unique electronic, thermal, mechanical, and chemical properties and potential technical applications. These remarkable characteristics of graphene, along with the inherent benefits of a carbon material, make it a promising candidate for application in electrochemical energy devices. This article reviews the methods of graphene preparation, introduces the unique electrochemical behavior of graphene, and summarizes the recent research and development on graphene-based fuel cells, supercapacitors and lithium ion batteries. In addition, promising areas are identified for the future development of graphene-based materials in electrochemical energy conversion and storage systems.

  11. Lithium-Ion (de)insertion reaction of Germanium thin-film electrodes : an electrochemical and in situ XRD study

    NARCIS (Netherlands)

    Baggetto, L.; Notten, P.H.L.

    2009-01-01

    Germanium is a promising negative electrode candidate for lithium-ion thin-film batteries because of its very high theoretical storage capacity. When assuming full conversion of the material into the room-temperature equilibrium lithium saturated germanium phase, a theoretical capacity of or of

  12. Electrochemical characterization of silicon/graphene/MWCNT hybrid lithium-ion battery anodes produced via RF magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Toçoğlu, Ubeyd, E-mail: utocoglu@sakarya.edu.tr; Hatipoğlu, Gizem; Alaf, Miraç; Kayış, Fuat; Akbulut, Hatem

    2016-12-15

    Graphical abstract: Silicon/graphene/MWCNT hybrid composite anodes were produced via RF magnetron sputtering technique. CR2016 type coin cells were assembled for electrochemical characterization of anodes. Electrochemical characterizations of anodes were conducted via galvanostatic charge/discharge, cyclic voltammetry and electrochemical impedance spectroscopy techniques. - Highlights: • Silicon/graphene/MWCNT hybrid negative lithium ion battery anodes were produced via magnetron sputtering. • Structural and electrochemical characterizations of composite anodes were conducted comprehensively. • The capacity values exhibited by composite anodes were found to be almost more than two times compared to thin film anodes after 100 cycles. - Abstract: In this study it was aimed to enhance cycling performance of silicon lithium ion battery anodes via producing flexible Silicon/Graphene/MWCNT composite structures. The volumetric expansions, which are the primary obstacle that hinders the practical usage of silicon anodes, were tried to suppress using flexible graphene/MWCNT paper substrates. Moreover to achieve lightweight and high electrical conductive anodes, the advantage of graphene was aimed to be exploited. Silicon/graphene/MWCNT flexible composite anodes were produced via radio frequency (RF) magnetron sputtering technique. Graphene/MWCNT papers were produced with vacuum filtration technique as substrate for sputtering process. At coating process of papers constant sputtering power was applied. Phase analysis was conducted with X-ray diffraction (XRD) technique and Raman spectroscopy. Field emission scanning electron microscopy (FESEM). Cyclic voltammetry (CV) tests were carried out to reveal reversible reactions between silicon and lithium. Galvanostatic charge/discharge technique was employed to determine the cyclic performance of anodes. Electrochemical impedance spectroscopy technique was used to understand the relation between cyclic performance and

  13. Electrochemical characterization of silicon/graphene/MWCNT hybrid lithium-ion battery anodes produced via RF magnetron sputtering

    International Nuclear Information System (INIS)

    Toçoğlu, Ubeyd; Hatipoğlu, Gizem; Alaf, Miraç; Kayış, Fuat; Akbulut, Hatem

    2016-01-01

    Graphical abstract: Silicon/graphene/MWCNT hybrid composite anodes were produced via RF magnetron sputtering technique. CR2016 type coin cells were assembled for electrochemical characterization of anodes. Electrochemical characterizations of anodes were conducted via galvanostatic charge/discharge, cyclic voltammetry and electrochemical impedance spectroscopy techniques. - Highlights: • Silicon/graphene/MWCNT hybrid negative lithium ion battery anodes were produced via magnetron sputtering. • Structural and electrochemical characterizations of composite anodes were conducted comprehensively. • The capacity values exhibited by composite anodes were found to be almost more than two times compared to thin film anodes after 100 cycles. - Abstract: In this study it was aimed to enhance cycling performance of silicon lithium ion battery anodes via producing flexible Silicon/Graphene/MWCNT composite structures. The volumetric expansions, which are the primary obstacle that hinders the practical usage of silicon anodes, were tried to suppress using flexible graphene/MWCNT paper substrates. Moreover to achieve lightweight and high electrical conductive anodes, the advantage of graphene was aimed to be exploited. Silicon/graphene/MWCNT flexible composite anodes were produced via radio frequency (RF) magnetron sputtering technique. Graphene/MWCNT papers were produced with vacuum filtration technique as substrate for sputtering process. At coating process of papers constant sputtering power was applied. Phase analysis was conducted with X-ray diffraction (XRD) technique and Raman spectroscopy. Field emission scanning electron microscopy (FESEM). Cyclic voltammetry (CV) tests were carried out to reveal reversible reactions between silicon and lithium. Galvanostatic charge/discharge technique was employed to determine the cyclic performance of anodes. Electrochemical impedance spectroscopy technique was used to understand the relation between cyclic performance and

  14. 6Li MAS NMR Study of Lithium Insertion into Hydrothermally Prepared Li-Ti-O Spinel

    Czech Academy of Sciences Publication Activity Database

    Krtil, Petr; Dědeček, Jiří; Kostlánová, Tereza; Brus, Jiří

    2004-01-01

    Roč. 7, č. 7 (2004), A163-A166 ISSN 1099-0062 R&D Projects: GA ČR GA203/03/0823 Institutional research plan: CEZ:AV0Z4040901 Keywords : lithium insertion * spinel * NMR Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.271, year: 2004

  15. Effects of synthetic parameters on structure and electrochemical performance of spinel lithium manganese oxide by citric acid-assisted sol-gel method

    International Nuclear Information System (INIS)

    Yi Tingfeng; Dai Changsong; Gao Kun; Hu Xinguo

    2006-01-01

    The spinel lithium manganese oxide cathode materials were prepared by citric acid-assisted sol-gel method at 623-1073 K in air. The effects of pH value, raw material, synthesis temperature and time on structure and electrochemical performance of spinel lithium manganese oxide are investigated by X-ray diffraction (XRD), scanning electronic microscope (SEM) and cyclic voltammetry (CV). XRD data results strongly suggest that the synthesis temperature is the dominating factors of the formation of spinel phase, and spinel lithium manganese oxide powder with various crystallites size can be obtained by controlling the sintering time. CV shows that spinel lithium manganese oxide powder formed about 973 K presents the best electrochemical performance with well separated two peaks and the highest peak current. Charge-discharge test indicates that spinel lithium manganese oxide powders calcined at higher temperatures have high discharge capacity and capacity loss, and sintered at lower temperatures has low discharge capacity and high capacity retention

  16. Effects of synthetic parameters on structure and electrochemical performance of spinel lithium manganese oxide by citric acid-assisted sol-gel method

    Energy Technology Data Exchange (ETDEWEB)

    Yi Tingfeng [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)]. E-mail: tfyihit@hit.edu.cn; Dai Changsong [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Gao Kun [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China); Hu Xinguo [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)

    2006-11-30

    The spinel lithium manganese oxide cathode materials were prepared by citric acid-assisted sol-gel method at 623-1073 K in air. The effects of pH value, raw material, synthesis temperature and time on structure and electrochemical performance of spinel lithium manganese oxide are investigated by X-ray diffraction (XRD), scanning electronic microscope (SEM) and cyclic voltammetry (CV). XRD data results strongly suggest that the synthesis temperature is the dominating factors of the formation of spinel phase, and spinel lithium manganese oxide powder with various crystallites size can be obtained by controlling the sintering time. CV shows that spinel lithium manganese oxide powder formed about 973 K presents the best electrochemical performance with well separated two peaks and the highest peak current. Charge-discharge test indicates that spinel lithium manganese oxide powders calcined at higher temperatures have high discharge capacity and capacity loss, and sintered at lower temperatures has low discharge capacity and high capacity retention.

  17. The use of odd random phase electrochemical impedance spectroscopy to study lithium-based corrosion inhibition by active protective coatings

    NARCIS (Netherlands)

    Meeusen, M.; Visser, P.; Fernández Macía, L.; Hubin, A.; Terryn, H.A.; Mol, J.M.C.

    2018-01-01

    In this work, the study of the time-dependent behaviour of lithium carbonate based inhibitor technology for the active corrosion protection of aluminium alloy 2024-T3 is presented. Odd random phase electrochemical impedance spectroscopy (ORP-EIS) is selected as the electrochemical tool to study

  18. Structural and electrochemical study of the reaction of lithium with silicon nanowires

    KAUST Repository

    Chan, Candace K.

    2009-04-01

    The structural transformations of silicon nanowires when cycled against lithium were evaluated using electrochemical potential spectroscopy and galvanostatic cycling. During the charge, the nanowires alloy with lithium to form an amorphous LixSi compound. At potentials <50 mV, a structural transformation occurs. In studies on micron-sized particles previously reported in the literature, this transformation is a crystallization to a metastable Li15Si4 phase. X-ray diffraction measurements on the Si nanowires, however, show that they are amorphous, suggesting that a different amorphous phase (LiySi) is formed. Lithium is removed from this phase in the discharge to form amorphous silicon. We have found that limiting the voltage in the charge to 70 mV results in improved efficiency and cyclability compared to charging to 10 mV. This improvement is due to the suppression of the transformation at low potentials, which alloys for reversible cycling of amorphous silicon nanowires. © 2008 Elsevier B.V. All rights reserved.

  19. Study on the electrochemical of the metal deposition from ionic liquids for lithium, titanium and dysprosium

    International Nuclear Information System (INIS)

    Berger, Claudia A.

    2017-01-01

    The thesis was aimed to the characterization of electrochemically deposited film of lithium, titanium and dysprosium on Au(111) from different ionic liquids, finally dysprosium on neodymium-iron-boron magnate for industrial applications. The investigation of the deposits were performed using cyclic voltametry, in-situ scanning tunneling microscopy, electrochemical quartz microbalance, XPS and Auger electron spectroscopy. The sample preparation is described in detail. The deposition rate showed a significant temperature dependence.

  20. Graphene-based electrochemical energy conversion and storage: fuel cells, supercapacitors and lithium ion batteries.

    Science.gov (United States)

    Hou, Junbo; Shao, Yuyan; Ellis, Michael W; Moore, Robert B; Yi, Baolian

    2011-09-14

    Graphene has attracted extensive research interest due to its strictly 2-dimensional (2D) structure, which results in its unique electronic, thermal, mechanical, and chemical properties and potential technical applications. These remarkable characteristics of graphene, along with the inherent benefits of a carbon material, make it a promising candidate for application in electrochemical energy devices. This article reviews the methods of graphene preparation, introduces the unique electrochemical behavior of graphene, and summarizes the recent research and development on graphene-based fuel cells, supercapacitors and lithium ion batteries. In addition, promising areas are identified for the future development of graphene-based materials in electrochemical energy conversion and storage systems. This journal is © the Owner Societies 2011

  1. Layered titanium disilicide stabilized by oxide coating for highly reversible lithium insertion and extraction.

    Science.gov (United States)

    Zhou, Sa; Simpson, Zachary I; Yang, Xiaogang; Wang, Dunwei

    2012-09-25

    The discovery of new materials has played an important role in battery technology development. Among the newly discovered materials, those with layered structures are often of particular interest because many have been found to permit highly repeatable ionic insertion and extraction. Examples include graphite and LiCoO(2) as anode and cathode materials, respectively. Here we report C49 titanium disilicide (TiSi(2)) as a new layered anode material, within which lithium ions can react with the Si-only layers. This result is enabled by the strategy of coating a thin (lithium-ion storage capacity of TiSi(2) is a result of its layered structure is expected to have major fundamental and practical implications.

  2. Electrochemical performances and capacity fading behaviors of activated carbon/hard carbon lithium ion capacitor

    International Nuclear Information System (INIS)

    Sun, Xianzhong; Zhang, Xiong; Liu, Wenjie; Wang, Kai; Li, Chen; Li, Zhao; Ma, Yanwei

    2017-01-01

    Highlights: • Three-electrode pouch cell is used to investigate the capacity fading of AC/HC LIC. • the electrode potential swing is critical for the cycleability of a LIC cell. • Different capacity fading behaviors are discussed. • A large-capacity LIC pouch cell has been assembled with a specific energy of 18.1 Wh kg −1 based on the total weight. - Abstract: Lithium ion capacitor (LIC) is one of the most promising electrochemical energy storage devices, which offers rapid charging-discharging capability and long cycle life. We have fabricated LIC pouch cells using an electrochemically-driven lithium pre-doping method through a three-electrode pouch cell structure. The active materials of cathode and anode of LIC cell are activated carbon and pre-lithiated hard carbon, respectively. The electrochemical performances and the capacity fading behaviors of LICs in the voltage range of 2.0 − 4.0 V have been studied. The specific energy and specific power reach 73.6 Wh kg −1 and 11.9 kW kg −1 based on the weight of the active materials in both cathode and anode, respectively. Since the cycling performance is actually determined by hard carbon anode, the anode potential swings are emphasized. The capacity fading of LIC upon cycling is proposed to be caused by the increases of internal resistance and the consumption of lithium stored in anode. Finally, a large-capacity LIC pouch cell has been assembled with a maximum specific energy of 18.1 Wh kg −1 and a maximum specific power of 3.7 kW kg −1 based on the weight of the whole cell.

  3. The effects of electrode thickness on the electrochemical and thermal characteristics of lithium ion battery

    International Nuclear Information System (INIS)

    Zhao, Rui; Liu, Jie; Gu, Junjie

    2015-01-01

    Highlights: • A coupling model is developed to study the behaviors of Li-ion batteries. • Thick electrode battery (CEB) has high temperature response during discharge. • Thin electrode battery has a relative lower capacity fading rate. • Less heat is generated in thin electrode battery with even heat distribution. • CEBs underutilize active materials and stop discharge early at high rates. - Abstract: Lithium ion (Li-ion) battery, consisting of multiple electrochemical cells, is a complex system whose high electrochemical and thermal stability is often critical to the well-being and functional capabilities of electric devices. Considering any change in the specifications may significantly affect the overall performance and life of a battery, an investigation on the impacts of electrode thickness on the electrochemical and thermal properties of lithium-ion battery cells based on experiments and a coupling model composed of a 1D electrochemical model and a 3D thermal model is conducted in this work. In-depth analyses on the basis of the experimental and simulated results are carried out for one cell of different depths of discharge as well as for a set of cells with different electrode thicknesses. Pertinent results have demonstrated that the electrode thickness can significantly influence the battery from many key aspects such as energy density, temperature response, capacity fading rate, overall heat generation, distribution and proportion of heat sources

  4. Correlations among structure, composition and electrochemical performances of WO3 anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Li, Pu; Li, Xing; Zhao, Ziyan; Wang, Mingshan; Fox, Thomas; Zhang, Qian; Zhou, Ying

    2016-01-01

    Highlights: • The residual precursor ions affect the charge/discharge performances of WO 3 . • Lithiated monoclinic WO 3 reveals the best discharge capacity. • Lithiation can enhance the conductivity of WO 3 . - Abstract: Suitable host structure for lithium insertion and extraction is crucial for lithium-ion batteries. Tungsten trioxides (WO 3 ) are particularly interesting materials for this purpose. In this work, the influences of structure and composition of WO 3 on the charge/discharge performances of Li-ion batteries are systematically investigated. Firstly, lithiated tungsten trioxides (Li-WO 3 ) are successfully synthesized by a hydrothermal method followed by annealing at different temperatures (200–600 °C). It is found that the hexagonal framework collapses and gradually transforms to the monoclinic phase due to the release of NH 4 + and NH 3 molecules. Unexpectedly, monoclinic WO 3 reveals better performances than that of hexagonal WO 3 . Among all the investigated samples, the lithiated WO 3 annealed at 500 °C exhibits the highest discharge capacity and cycle performance (703 mAh g −1 after 10 cycles). We believe that the Li + remained in the solid structure of WO 3 can lead to a more stable structure. In addition, Li + could inhibit the oxidation of W 5+ during the heat treatment process, which increases the electron conductivity of WO 3 . Our results indicate that the electrochemical properties of WO 3 are strongly related to the residual precursor and crystal structure.

  5. Electrochemical properties of Super P carbon black as an anode active material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Gnanamuthu, RM.; Lee, Chang Woo

    2011-01-01

    Highlights: → A novel attempt of Super P carbon black as an anode active material for lithium-ion batteries. → The first discharge capacity was approximately 1256 mAh g -1 and at the end of 20th cycling the capacity was 610 mAh g -1 at 0.1 C rate. → Coulombic efficiency of Super P carbon black electrode was maintained about 84% at the end of cycling. - Abstract: A new approach to investigate upon the electrochemical properties of Super P carbon black anode material is attempted and compared with conventional mesophase pitch-based carbon fibers (MPCFs) anode material for lithium-ion batteries. The prepared Super P carbon black electrodes are characterized using transmission electron microscope (TEM). The assembled 2032-type coin cells are electrochemically characterized by ac impedance spectroscopic and cyclic voltammetric methods. The electrochemical performance of charge and discharge was analyzed using a battery cycler at 0.1 C rate and cut-off potentials of 1.20 and 0.01 V vs. Li/Li + . The electrochemical test illustrates that the discharge capacity corresponding to Li intercalation into the Super P carbon black electrode is higher and coulombic efficiency is maintained approximately 84% at the end of the 20th cycling at room temperature.

  6. Electrochemical characteristics of bundle-type silicon nanorods as an anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Nguyen, Si Hieu; Lim, Jong Choo; Lee, Joong Kee

    2012-01-01

    Highlights: ► A metal-assisted chemical etching technique was performed on Si thin films. ► The etching process resulted in the formation of bundle-type Si nanorods. ► The morphology of Si electrodes closely relate to electrochemical characteristics. - Abstract: In order to prepare bundle-type silicon nanorods, a silver-assisted chemical etching technique was used to modify a 1.6 μm silicon thin film, which was deposited on Cu foil by Electron Cyclotron Resonance Plasma Enhanced Chemical Vapor Deposition. The bundle-type silicon nanorods on Cu foil were employed as anodes for a lithium secondary battery, without further treatment. The electrochemical characteristics of the pristine silicon thin film anodes and the bundle-type silicon nanorod anodes are different from one another. The electrochemical performance of the bundle-type silicon nanorod anodes exceeded that of the pristine Si thin film anodes. The specific capacity of the bundle-type silicon nanorod anodes is much higher than 3000 mAh g −1 at the first charge (Li insertion) cycle. The coulombic efficiency of bundle-type silicon anodes was stable at more than 97%, and the charge capacity remained at 1420 mAh g −1 , even after 100 cycles of charging and discharging. The results from the differential voltage analysis showed a side reaction at around 0.44–0.5 V, and the specific potential of this side reaction decreased after each cycle. The apparent diffusion coefficients of the two anode types were in the range of 10 −13 –10 −16 cm 2 s −1 in the first cycle. In subsequent charge cycles, these values for the silicon thin film anodes and the silicon nanorod bundle anode were approximately 10 −12 –10 −14 and 10 −13 –10 −15 cm 2 s −1 , respectively.

  7. Conductive surface modification of cauliflower-like WO3 and its electrochemical properties for lithium-ion batteries

    International Nuclear Information System (INIS)

    Yoon, Sukeun; Woo, Sang-Gil; Jung, Kyu-Nam; Song, Huesup

    2014-01-01

    Highlights: • Synthesis of cauliflower-like carbon-decorated WO 3 . • Superior cyclability and rate capability for cauliflower-like carbon-decorated WO 3 . • Electrochemical reaction behavior of cauliflower-like carbon-decorated WO 3 with lithium. • In-situ XRD analysis during the first discharge–charge shows a complex reaction of intercalation and conversion of WO 3 . - Abstract: Cauliflower-like WO 3 was synthesized by a hydrothermal reaction without a surfactant, followed by firing, and was investigated as an anode material for lithium-ion battery applications. The scanning electron microscope (SEM) and transmission electron microscope (TEM) characterization indicated that WO 3 nanorods had an aggregation framework and built a cauliflower morphology. With the objective of understanding the charge–discharge process within a voltage range of 0–3 V vs. Li + /Li, in situ X-ray diffraction was used and a complex reaction of intercalation and conversion of WO 3 was revealed for the first time. The cauliflower-like WO 3 after being decorated with carbon provides a high gravimetric capacity of >635 mA h/g (Li 5.5 WO 3 ) with good cycling and a high rate capability when used as an anode in lithium-ion batteries. Based on our studies, we attribute the high electrochemical performance to the nanoscopic WO 3 particles and a conductive carbon layer, which makes them a potential candidate for lithium-ion batteries

  8. Microwave-assisted Synthesis of CuS/Graphene Composite for Enhanced Lithium Storage Properties

    International Nuclear Information System (INIS)

    Li, He; Wang, Yunhui; Huang, Jingxin; Zhang, Yiyong; Zhao, Jinbao

    2017-01-01

    Highlights: • CuS/graphene composite is synthesized via one-pot microwave-assisted method. • CuS/graphene composite shows enhanced cycle stability and rate performance. • The incorporation of graphene plays a vital role in the electrode. • The kinetic mechanisms are investigated by EIS, CV and GITT methods. - Abstract: In this work, CuS/graphene (CuS-G) composite is synthesized via one-pot microwave irradiation method under ambient conditions. As anode material for lithium ion batteries, the CuS-G composite delivers a significantly enhanced reversible capacity and charge/discharge cycle stability compared with pristine CuS. A capacity of 348 mAh g −1 can be maintained after 1000 cycles at the current density of 2.0 A g −1 . Electrochemical impedance spectroscopy (EIS) along with cyclic voltammetry (CV) and galvanostatic intermittent titration technique (GITT) measurements indicate that the incorporation of graphene sheets reduces the contact resistance and enhances lithium ion transfer rate during the electrochemical lithium insertion/extraction remarkably. Thus, as-prepared CuS spheres can be a promising anode material for high performance lithium ion batteries.

  9. Enhanced electrochemical properties of LiFePO4 (LFP) cathode using the carboxymethyl cellulose lithium (CMC-Li) as novel binder in lithium-ion battery.

    Science.gov (United States)

    Qiu, Lei; Shao, Ziqiang; Wang, Daxiong; Wang, Wenjun; Wang, Feijun; Wang, Jianquan

    2014-10-13

    Novel water-based binder CMC-Li is synthesized using cotton as raw material. The mechanism of the CMC-Li as a binder is reported. Electrochemical properties of batteries cathodes based on commercially available lithium iron phosphate (LiFePO4, LFP) and CMC-Li as a water-soluble binder are investigated. CMC-Li is a novel lithium-ion binder. Compare with conventional poly(vinylidene fluoride) (PVDF) binder, and the battery with CMC-Li as the binder retained 97.8% of initial reversible capacity after 200 cycles at 176 mAh g(-1), which is beyond the theoretical specific capacity of LFP. Constant current charge-discharge test results demonstrate that the LFP electrode using CMC-Li as the binder has the highest rate capability, follow closely by that using PVDF binder. The batteries have good electrochemical property, outstanding pollution-free and excellent stability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Temperature dependence of electrochemical properties of cross-linked poly(ethylene oxide)–lithium bis(trifluoromethanesulfonyl)imide–N-butyl-N-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide solid polymer electrolytes for lithium batteries

    International Nuclear Information System (INIS)

    Wetjen, Morten; Kim, Guk-Tae; Joost, Mario; Winter, Martin; Passerini, Stefano

    2013-01-01

    Highlights: ► Solid-state electrolyte for lithium batteries. ► Polymer electrolyte with improved mechanical properties by cross-linking. ► Enhanced performance of polymer electrolytes using water- and air-stable ionic liquids as co-salts. ► Polymer electrolyte with high rate capability at moderate temperatures. - Abstract: An advanced electrochemical characterization of cross-linked ternary solid polymer electrolytes (SPEs), prepared by a solvent-free hot-pressing process, is reported. Ionic conductivity, electrochemical stability window and limiting current measurements were performed as a function of the temperature by using both potentiodynamic and galvanostatic techniques. Additionally, the lithium cycleability was evaluated with respect to its dependence on both the operating temperature and the current density by using a new multi-rate Li-stripping-plating procedure. The results clearly indicate the beneficial effect of higher operating temperatures on the rate-capability, without major degradation of the electrochemical stability of the SPE. All-solid-state lithium metal polymer batteries (LMPBs), comprising a lithium metal anode, the cross-linked ternary solid polymer electrolyte and a LiFePO 4 composite cathode, were manufactured and investigated in terms of the interdependencies of the delivered capacity, operating temperature and discharge rate. The results prove quite exceptional delivered capacities both at medium current densities at ambient temperatures and even more impressive capacities above 160 mAh g −1 at high discharge rates (1 C) and temperatures above 60 °C.

  11. Improved Electrochemical Performance of Biomass-Derived Nanoporous Carbon/Sulfur Composites Cathode for Lithium-Sulfur Batteries by Nitrogen Doping

    International Nuclear Information System (INIS)

    Geng, Zhen; Xiao, Qiangfeng; Wang, Dabin; Yi, Guanghai; Xu, Zhigang; Li, Bing; Zhang, Cunman

    2016-01-01

    A two-step method with high-efficiency is developed to prepare nitrogen doped activated carbons (NACs) with high surface area and nitrogen content. Based on the method, series of NACs with similar surface area and pore texture but different nitrogen content and nitrogen group species are successfully prepared. The influence of nitrogen doping on electrochemical performance of carbon/sulfur composites cathode is studied deeply under the conditions of similar surface area and pore texture. It presents the directly experimental demonstration that both nitrogen content and nitrogen group species play crucial roles on electrochemical performance of carbon/sulfur composites cathode. NAC/sulfur composites show the much improved cycling performance, which is about 3.5 times as that of nitrogen free carbon. Improved electrochemical performance is due to synergistic effects between nitrogen content and effective nitrogen groups, which enables effective trapping of lithium polysulfides within carbon framework. Besides, it is found that oxygen groups exist in carbon materials obviously influence electrochemical performance of cathode, which could be ignored in most of studies. Based on above, it can be concluded that enhanced chemisorption to lithium polysulfides by functional groups modification is the effective route to improve the electrochemical performance of Li-S battery.

  12. Electrochemical characteristics of TiS/sub 2/, ZrSe/sub 2/ and VSe/sub 2/ in secondary lithium battery

    Energy Technology Data Exchange (ETDEWEB)

    Onuki, Y; Inada, R; Tanuma, S; Yamanaka, S; Kamimura, H

    1981-08-01

    The layered transition metal dichalcogenides of TiS/sub 2/, ZrSe/sub 2/ and VSe/sub 2/ were found to react reversibly with lithium in electrochemical cells. The energy densities of these cathode materials were determined to be 500, 240 and 250 W.h/kg for one lithium intercalation per unit cell, respectively, and 420 W.h/kg for two lithium intercalation per unit cell of VSe/sub 2/. It was found for ZrSe/sub 2/ that more than two lithium ions per unit cell can be intercalated in the first discharge when the cell temperature is increased to 60/sup 0/C, while one lithium ion can be intercalated at 20/sup 0/C. 5 refs.

  13. Electrochemical-mechanical coupled modeling and parameterization of swelling and ionic transport in lithium-ion batteries

    Science.gov (United States)

    Sauerteig, Daniel; Hanselmann, Nina; Arzberger, Arno; Reinshagen, Holger; Ivanov, Svetlozar; Bund, Andreas

    2018-02-01

    The intercalation and aging induced volume changes of lithium-ion battery electrodes lead to significant mechanical pressure or volume changes on cell and module level. As the correlation between electrochemical and mechanical performance of lithium ion batteries at nano and macro scale requires a comprehensive and multidisciplinary approach, physical modeling accounting for chemical and mechanical phenomena during operation is very useful for the battery design. Since the introduced fully-coupled physical model requires proper parameterization, this work also focuses on identifying appropriate mathematical representation of compressibility as well as the ionic transport in the porous electrodes and the separator. The ionic transport is characterized by electrochemical impedance spectroscopy (EIS) using symmetric pouch cells comprising LiNi1/3Mn1/3Co1/3O2 (NMC) cathode, graphite anode and polyethylene separator. The EIS measurements are carried out at various mechanical loads. The observed decrease of the ionic conductivity reveals a significant transport limitation at high pressures. The experimentally obtained data are applied as input to the electrochemical-mechanical model of a prismatic 10 Ah cell. Our computational approach accounts intercalation induced electrode expansion, stress generation caused by mechanical boundaries, compression of the electrodes and the separator, outer expansion of the cell and finally the influence of the ionic transport within the electrolyte.

  14. Lithium-ions diffusion kinetic in LiFePO4/carbon nanoparticles synthesized by microwave plasma chemical vapor deposition for lithium-ion batteries

    Science.gov (United States)

    Gao, Chao; Zhou, Jian; Liu, Guizhen; Wang, Lin

    2018-03-01

    Olivine structure LiFePO4/carbon nanoparticles are synthesized successfully using a microwave plasma chemical vapor deposition (MPCVD) method. Microwave is an effective method to synthesize nanomaterials, the LiFePO4/carbon nanoparticles with high crystallinity can shorten diffusion routes for ionic transfer and electron tunneling. Meanwhile, a high quality, complete and homogenous carbon layer with appropriate thickness coating on the surface of LiFePO4 particles during in situ chemical vapor deposition process, which can ensure that electrons are able to transfer fast enough from all sides. Electrochemical impedance spectroscopy (EIS) is carried out to collect information about the kinetic behavior of lithium diffusion in LiFePO4/carbon nanoparticles during the charging and discharging processes. The chemical diffusion coefficients of lithium ions, DLi, are calculated in the range of 10-15-10-9 cm2s-1. Nanoscale LiFePO4/carbon particles show the longer regions of the faster solid-solution diffusion, and corresponding to the narrower region of the slower two-phase diffusion during the insertion/exaction of lithium ions. The CV and galvanostatic charge-discharge measurements show that the LiFePO4/carbon nanoparticles perform an excellent electrochemical performance, especially the high rate capacity and cycle life.

  15. Electrochemically oxidized electronic and ionic conducting nanostructured block copolymers for lithium battery electrodes.

    Science.gov (United States)

    Patel, Shrayesh N; Javier, Anna E; Balsara, Nitash P

    2013-07-23

    Block copolymers that can simultaneously conduct electronic and ionic charges on the nanometer length scale can serve as innovative conductive binder material for solid-state battery electrodes. The purpose of this work is to study the electronic charge transport of poly(3-hexylthiophene)-b-poly(ethylene oxide) (P3HT-PEO) copolymers electrochemically oxidized with lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) salt in the context of a lithium battery charge/discharge cycle. We use a solid-state three-terminal electrochemical cell that enables simultaneous conductivity measurements and control over electrochemical doping of P3HT. At low oxidation levels (ratio of moles of electrons removed to moles of 3-hexylthiophene moieties in the electrode), the electronic conductivity (σe,ox) increases from 10(-7) S/cm to 10(-4) S/cm. At high oxidation levels, σe,ox approaches 10(-2) S/cm. When P3HT-PEO is used as a conductive binder in a positive electrode with LiFePO4 active material, P3HT is electrochemically active within the voltage window of a charge/discharge cycle. The electronic conductivity of the P3HT-PEO binder is in the 10(-4) to 10(-2) S/cm range over most of the potential window of the charge/discharge cycle. This allows for efficient electronic conduction, and observed charge/discharge capacities approach the theoretical limit of LiFePO4. However, at the end of the discharge cycle, the electronic conductivity decreases sharply to 10(-7) S/cm, which means the "conductive" binder is now electronically insulating. The ability of our conductive binder to switch between electronically conducting and insulating states in the positive electrode provides an unprecedented route for automatic overdischarge protection in rechargeable batteries.

  16. Electrochemical performance of high specific capacity of lithium-ion cell LiV3O8//LiMn2O4 with LiNO3 aqueous solution electrolyte

    International Nuclear Information System (INIS)

    Zhao Mingshu; Zheng Qingyang; Wang Fei; Dai Weimin; Song Xiaoping

    2011-01-01

    Research highlights: → In this paper, the electrochemical performance of aqueous rechargeable lithium battery with LiV 3 O 8 and LiMn 2 O 4 in saturated LiNO 3 electrolyte is studied. → The electrochemical performance tests show that the specific capacity of LiMn 2 O 4 using as the cathode of ARLB is similar to that of ordinary lithium-ion battery with organic electrolyte, which works much better than the formerly reported. → In addition, the cell systems exhibit good cycling performance. Therefore, it has great potential comparing with other batteries such as lead acid batteries and alkaline manganese batteries. - Abstract: The electrochemical performance of aqueous rechargeable lithium battery (ARLB) with LiV 3 O 8 and LiMn 2 O 4 in saturated LiNO 3 electrolyte is studied. The results indicate that these two electrode materials are stable in the aqueous solution and no hydrogen or oxygen produced, moreover, intercalation/de-intercalation of lithium ions occurred within the range of electrochemical stability of water. The electrochemical performance tests show that the specific capacity of LiMn 2 O 4 using as the cathode of ARLB is similar to that of ordinary lithium-ion battery with organic electrolyte, which works much better than the formerly reported. In addition, the cell systems exhibit good cycling performance. Therefore, it has great potential comparing with other batteries such as lead acid batteries and alkaline manganese batteries.

  17. Performance of titanium dioxide-based cathodes in a lithium polymer electrolyte cell

    Energy Technology Data Exchange (ETDEWEB)

    Macklin, W.J. (Applied Electrochemistry Dept., AEA Industry Technology, Harwell (United Kingdom)); Neat, R.J. (Applied Electrochemistry Dept., AEA Industry Technology, Harwell (United Kingdom))

    Performance data on two polymorphs of titanium dioxide (anatase and rutile) operating in a lithium polymer electrolyte cell at 120 C are presented. On the first discharge lithium ions can be electrochemically inserted into both forms to an approximate composition LiTiO[sub 2]. However, only the rutile material cycles with a significant capacity ([proportional to] 0.5 Li/TiO[sub 2]) with an average cell voltage of 1.73 V corresponding to a theoretical energy density of [proportional to] 290 W h kg[sup -1]. Our results are in contrast to earlier work reported on the intercalation of lithium into these phases at room temperature, where only the anatase form was found to intercalate lithium. X-ray diffraction data indicate that the rutile form undergoes a structural change during the first discharge resulting in the formation of a hexagonal form of LiTiO[sub 2].

  18. Thermo-electrochemical model for forced convection air cooling of a lithium-ion battery module

    International Nuclear Information System (INIS)

    Tong, Wei; Somasundaram, Karthik; Birgersson, Erik; Mujumdar, Arun S.; Yap, Christopher

    2016-01-01

    Highlights: • Coupled thermal-electrochemical model for a Li-ion battery module resolving every functional layer in all cells. • Parametric analysis of forced convection air cooling of Li-ion battery module with a detailed multi-scale model. • Reversing/reciprocating airflow for Li-ion battery module thermal management provides uniform temperature distribution. - Abstract: Thermal management is critical for safe and reliable operation of lithium-ion battery systems. In this study, a one-dimensional thermal-electrochemical model of lithium-ion battery interactively coupled with a two-dimensional thermal-fluid conjugate model for forced convection air cooling of a lithium-ion battery module is presented and solved numerically. This coupled approach makes the model more unique and detailed as transport inside each cell in the battery module is solved for and thus covering multiple length and time scales. The effect of certain design and operating parameters of the thermal management system on the performance of the battery module is assessed using the coupled model. It is found that a lower temperature increase of the battery module can be achieved by either increasing the inlet air velocity or decreasing the distance between the cells. Higher air inlet velocity, staggered cell arrangement or a periodic reversal airflow of high reversal frequency results in a more uniform temperature distribution in the module. However, doing so increases the parasitic load as well as the volume of the battery module whence a trade-off should be taken into account between these parameters.

  19. The impact of surface composition on Tafel kinetics leading to enhanced electrochemical insertion of hydrogen in palladium

    Science.gov (United States)

    Dmitriyeva, Olga; Hamm, Steven C.; Knies, David L.; Cantwell, Richard; McConnell, Matt

    2018-05-01

    Our previous work experimentally demonstrated the enhancement of electrochemical hydrogen insertion into palladium by modifying the chemical composition of the cathode surface with Pb, Pt and Bi, referred to as surface promoters. The experiment demonstrated that an optimal combination of the surface promoters led to an increase in hydrogen fugacity of more than three orders of magnitude, while maintaining the same current density. This manuscript discusses the application of Density Functional Theory (DFT) to elucidate the thermodynamics and kinetics of observed enhancement of electrochemical hydrogen insertion into palladium. We present theoretical simulations that: (1) establish the elevation of hydrogen's chemical potential on Pb and Bi surfaces to enhance hydrogen insertion, (2) confirm the increase of a Tafel activation barrier that results in a decrease of the reaction rate at the given hydrogen overpotential, and (3) explain why the surface promoter's coverage needs to be non-uniform, namely to allow hydrogen insertion into palladium bulk while simultaneously locking hydrogen below the surface (the corking effect). The discussed DFT-based method can be used for efficient scanning of different material configurations to design a highly effective hydrogen storage system.

  20. Electrochemical characterization of electrolytes and electrodes for lithium-ion batteries. Development of a new measuring method for electrochemical investigations on electrodes with the electrochemical quartz crystal microbalance (EQCM); Elektrochemische Charakterisierung von Elektrolyten und Elektroden fuer Lithium-Ionen-Batterien. Entwicklung einer neuen Messmethode fuer elektrochemische Untersuchungen an Elektroden mit der EQCM

    Energy Technology Data Exchange (ETDEWEB)

    Moosbauer, Dominik Johann

    2010-11-09

    In this work the conductivities of four different lithium salts, LiPF6, LiBF4, LiDFOB, and LiBOB in the solvent mixture EC/DEC (3/7) were investigated. Furthermore, the influence of eight ionic liquids (ILs) as additives on the conductivity and electrochemical stability of lithium salt-based electrolytes was studied. The investigated salts were the well-known lithium LiPF6 and LiDFOB. Conductivity studies were performed over the temperature range (238.15 to 333.15) K. The electrochemical stabilities of the solutions were determined at aluminum electrodes. The salt solubility of LiBF4 and LiDFOB in EC/DEC (3/7) was measured with the quartz crystal microbalance (QCM), a method developed in our group. Moreover, a method to investigate interactions between the electrolyte and electrode components with the electrochemical quartz crystal microbalance (EQCM) was developed. First, investigations of corrosion and passivation effects on aluminum with different lithium salts were performed and masses of deposited products estimated. Therefore, the quartzes were specially prepared with foils. Active materials of cathodes, in this work lithium iron phosphate (LiFePO4), were also investigated with the EQCM by a new method. [German] In dieser Arbeit wurden die Leitfaehigkeiten von vier unterschiedlichen Salzen, LiPF6, LiBF4, LiDFOB und LiBOB in dem Loesemittelgemisch EC/DEC (3/7) untersucht. Des Weiteren wurde der Einfluss von acht Ionischen Fluessigkeiten (ILs) als Additive fuer Lithium-Elektrolyte auf die elektrochemische Stabilitaet und die Leitfaehigkeit studiert. Die untersuchten Salze waren LiPF6 und LiDFOB. Die Leitfaehigkeitsmessungen wurden in einem Temperaturbereich von (238,15 bis 333,15) K durchgefuehrt. Die elektrochemischen Stabilitaeten der Elektrolyte fanden an Aluminium statt. Mit einer an der Arbeitsgruppe entwickelten neuen Methode wurden zudem die Salzloeslichkeiten von LiBF4 und LiDFOB in EC/DEC (3/7) mit der Quarzmikrowaage (QCM) bestimmt. Weiterhin wurden

  1. Electrochemically active manganese oxides: structural modelling, modifications induced by thermal processing and photon insertion

    International Nuclear Information System (INIS)

    Ripert, Michel

    1990-01-01

    The objective of this research study is to understand the mechanism of proton insertion into manganese dioxide. It comprised the performances of in situ discharges of two commercial samples in an electrochemical cell designed for this purpose. In order to characterise the structure of electrochemically active manganese dioxides, and particularly to elucidate the orthorhombic-hexagonal dilemma, the author proposes a crystalline-chemical approach which comprises the development of a unique structural model which takes the structure of all forms of electrochemically active manganese dioxides into account, and a numerical simulation of diffraction diagrams (X rays and neutrons) of these structures. The development of this modelling results in the development of a method which allows, from experimental diffraction diagrams, characteristic structural parameters of each sample of EMD (electrolytic manganese dioxide) or CMD (chemical manganese dioxide) to be obtained. Moreover, the observation of the structural evolution of the dioxide is possible by using in situ neutron diffraction. Reduction has been studied by using slow potential scanning voltammetry. By using these both techniques (neutron diffraction and voltammetry), it is possible to explain the structural mechanism of reduction of MnO_2 and to show the origin of the non-reversibility of the proton/MnO_2 system, to quantitatively explain the shape voltammetry curves, and to highlight experimentally for the first time the different sites of insertion of the proton

  2. Significantly enhanced electrochemical performance of lithium titanate anode for lithium ion battery by the hybrid of nitrogen and sulfur co-doped graphene quantum dots

    International Nuclear Information System (INIS)

    Ruiyi, Li; Yuanyuan, Jiang; Xiaoyan, Zhou; Zaijun, Li; Zhiguo, Gu; Guangli, Wang; Junkang, Liu

    2015-01-01

    Graphical abstract: The study reported a facile synthesis of Li4Ti5O12/nitrogen and sulfur co-doped graphene quantum dots (LTO/N,S-GQDs). The unique architecture and the introduction of N,S-GQDs create both ultrafast electron transfer and electrolyte transport. The as-prepared LTO/N,S-GQDs anode provides prominent advantage of specific capacity, high-rate performance and cycle stability. - Highlights: • We reported a new lithium titanate/nitrogen and sulfur co-doped graphene quantum dots hybrid • The synthesis creates a crystalline interconnected porous framework composed of nanoscale LTO • The unique architecture achieves to maximize the rate performance and enhance the power density • Introduction of N,S-GQDs greatly enhances the electron transfer and the storage lithium capacity • The hybrid anode provides an excellent electrochemical performance for lithium-ion batteries - ABSTRACT: The paper reported a facile synthesis of lithium titanate/nitrogen and sulfur co-doped graphene quantum dots(LTO/N,S-GQDs). Tetrabutyl titanate was dissolved in tertbutanol and heated to refluxing state by microwave irradiation. Then, lithium acetate was added into the mixed solution to produce LTO precursor. The precursor was hybridized with N,S-GQDs in ethanol. Followed by drying and thermal annealing at 500 °C in Ar/H_2 to obtain LTO/N,S-GQDs. The synthesis creates fully crystalline interconnected porous framework composed of nanoscale LTO crystals. The unique architecture achieves to maximize the high-rate performance and enhance the power density. More importantly, the introduction of N,S-GQDs don't almost influence on the electrolyte transport, but greatly improve the electron transfer and the storage lithium capacity. The LTO/N,S-GQDs anode exhibits remarkably enhanced electrochemical performance for lithium ion battery. The specific discharge capacity is 254.2 mAh g"−"1 at 0.1C and 126.5 mAh g"−"1 at 10C. The capacity remains 96.9% at least after 2000 cycles

  3. Non-isothermal electrochemical model for lithium-ion cells with composite cathodes

    Science.gov (United States)

    Basu, Suman; Patil, Rajkumar S.; Ramachandran, Sanoop; Hariharan, Krishnan S.; Kolake, Subramanya Mayya; Song, Taewon; Oh, Dukjin; Yeo, Taejung; Doo, Seokgwang

    2015-06-01

    Transition metal oxide cathodes for Li-ion batteries offer high energy density and high voltage. Composites of these materials have shown excellent life expectancy and improved thermal performance. In the present work, a comprehensive non-isothermal electrochemical model for a Lithium ion cell with a composite cathode is developed. The present work builds on lithium concentration-dependent diffusivity and thermal gradient of cathode potential, obtained from experiments. The model validation is performed for a wide range of temperature and discharge rates. Excellent agreement is found for high and room temperature with moderate success at low temperatures, which can be attributed to the low fidelity of material properties at low temperature. Although the cell operation is limited by electronic conductivity of NCA at room temperature, at low temperatures a shift in controlling process is seen, and operation is limited by electrolyte transport. At room temperature, the lithium transport in Cathode appears to be the main source of heat generation with entropic heat as the primary contributor at low discharge rates and ohmic heat at high discharge rates respectively. Improvement in electronic conductivity of the cathode is expected to improve the performance of these composite cathodes and pave way for its wider commercialization.

  4. Preparation of nano-porous LiNi0.5Mn1.5O4 with high electrochemical performances by a co-precipitation method for 5 V lithium-ion batteries

    Science.gov (United States)

    Cui, Xiaoling; Li, Hongliang; Li, Shiyou

    2017-10-01

    Porous LiNi0.5Mn1.5O4 is prepared by co-precipitation method. The results of scanning electron microscopy show that the sample has a nano-porous structure. Charge-discharge tests show that the synthesized product exhibits excellent electrochemical performance with a high initial discharge capacity of 129.1 mAh g-1 at 0.5 C and a preferably capacity retention of 96.5% after 200 cycles. The superior performance of the synthesized product is attributed to its nano-porous structure. The nanoparticle reduces the path of Li+ diffusion and increases the reaction sites for lithium insertion/extraction, the pores provide room to buffer the volume changes during charge-discharge.

  5. Results from a Novel Method for Corrosion Studies of Electroplated Lithium Metal Based on Measurements with an Impedance Scanning Electrochemical Quartz Crystal Microbalance

    Directory of Open Access Journals (Sweden)

    Martin Winter

    2013-07-01

    Full Text Available A new approach to study the chemical stability of electrodeposited lithium on a copper metal substrate via measurements with a fast impedance scanning electrochemical quartz crystal microbalance is presented. The corrosion of electrochemically deposited lithium was compared in two different electrolytes, based on lithium difluoro(oxalato borate (LiDFOB and lithium hexafluorophosphate, both salts being dissolved in solvent blends of ethylene carbonate and diethyl carbonate. For a better understanding of the corrosion mechanisms, scanning electron microscopy images of electrodeposited lithium were also consulted. The results of the EQCM experiments were supported by AC impedance measurements and clearly showed two different corrosion mechanisms caused by the different salts and the formed SEIs. The observed mass decrease of the quartz sensor of the LiDFOB-based electrolyte is not smooth, but rather composed of a series of abrupt mass fluctuations in contrast to that of the lithium hexafluorophosphate-based electrolyte. After each slow decrease of mass a rather fast increase of mass is observed several times. The slow mass decrease can be attributed to a consolidation process of the SEI or to the partial dissolution of the SEI leaving finally lithium metal unprotected so that a fast film formation sets in entailing the observed fast mass increases.

  6. Coupled Mechanical and Electrochemical Phenomena in Lithium-Ion Batteries

    Science.gov (United States)

    Cannarella, John

    Lithium-ion batteries are complee electro-chemo-mechanical systems owing to a number of coupled mechanical and electrochemical phenomena that occur during operation. In this thesis we explore these phenomena in the context of battery degradation, monitoring/diagnostics, and their application to novel energy systems. We begin by establishing the importance of bulk stress in lithium-ion batteries through the presentation of a two-year exploratory aging study which shows that bulk mechanical stress can significantly accelerate capacity fade. We then investigate the origins of this coupling between stress and performance by investigating the effects of stress in idealized systems. Mechanical stress is found to increase internal battery resistance through separator deformation, which we model by considering how deformation affects certain transport properties. When this deformation occurs in a spatially heterogeneous manner, local hot spots form, which accelerate aging and in some cases lead to local lithium plating. Because of the importance of separator deformation with respect to mechanically-coupled aging, we characterize the mechanical properties of battery separators in detail. We also demonstrate that the stress state of a lithium-ion battery cell can be used to measure the cell's state of health (SOH) and state of charge (SOC)--important operating parameters that are traditionally difficult to measure outside of a laboratory setting. The SOH is shown to be related to irreversible expansion that occurs with degradation and the SOC to the reversible strains characteristic of the cell's electrode materials. The expansion characteristics and mechanical properties of the constituent cell materials are characterized, and a phenomenological model for the relationship between stress and SOH/SOC is developed. This work forms the basis for the development of on-board monitoring of SOH/SOC based on mechanical measurements. Finally we study the coupling between mechanical

  7. Investigation of the electrochemically active surface area and lithium diffusion in graphite anodes by a novel OsO4 staining method

    Science.gov (United States)

    Pfaffmann, Lukas; Birkenmaier, Claudia; Müller, Marcus; Bauer, Werner; Mitsch, Tim; Feinauer, Julian; Krämer, Yvonne; Scheiba, Frieder; Hintennach, Andreas; Schleid, Thomas; Schmidt, Volker; Ehrenberg, Helmut

    2016-03-01

    Negative electrodes of lithium-ion batteries generally consist of graphite-based active materials. In order to realize batteries with a high current density and therefore accelerated charging processes, the intercalation of lithium and the diffusion processes of these carbonaceous materials must be understood. In this paper, we visualized the electrochemical active surface area for three different anode materials using a novel OsO4 staining method in combination with scanning electron microscopy techniques. The diffusion behavior of these three anode materials is investigated by potentiostatic intermittent titration technique measurements. From those we determine the diffusion coefficient with and without consideration of the electrochemical active surface area.

  8. Effect of Nickel Coated Multi-Walled Carbon Nanotubes on Electrochemical Performance of Lithium-Sulfur Rechargeable Batteries.

    Science.gov (United States)

    Wu, Xiao; Yao, Shanshan; Hou, Jinli; Jing, Maoxiang; Qian, Xinye; Shen, Xiangqian; Xiang, Jun; Xi, Xiaoming

    2017-04-01

    Conventional lithium-sulfur batteries suffer from severe capacity fade, which is induced by low electron conductivity and high dissolution of intermediated polysulfides. Recent studies have shown the metal (Pt, Au, Ni) as electrocatalyst of lithium polysulfides and improved the performance for lithium sulfur batteries. In this work, we present the nickel coated multi-walled carbon nanotubes (Ni-MWNTs) as additive materials for elemental sulfur positive electrodes for lithium-sulfur rechargeable batteries. Compared with MWNTs, the obtained Ni-MWNTs/sulfur composite cathode demonstrate a reversible specific capacity approaching 545 mAh after 200 cycles at a rate of 0.5C as well as improved cycling stability and excellent rate capacity. The improved electrochemical performance can be attributed to the fact the MWNTs shows a vital role on polysulfides adsorption and nickel has a catalytic effect on the redox reactions during charge–discharge process. Meanwhile, the Ni-MWNTs is a good electric conductor for sulfur cathode.

  9. Enhanced Lithium- and Sodium-Ion Storage in an Interconnected Carbon Network Comprising Electronegative Fluorine.

    Science.gov (United States)

    Hong, Seok-Min; Etacheri, Vinodkumar; Hong, Chulgi Nathan; Choi, Seung Wan; Lee, Ki Bong; Pol, Vilas G

    2017-06-07

    Fluorocarbon (C x F y ) anode materials were developed for lithium- and sodium-ion batteries through a facile one-step carbonization of a single precursor, polyvinylidene fluoride (PVDF). Interconnected carbon network structures were produced with doped fluorine in high-temperature carbonization at 500-800 °C. The fluorocarbon anodes derived from the PVDF precursor showed higher reversible discharge capacities of 735 mAh g -1 and 269 mAh g -1 in lithium- and sodium-ion batteries, respectively, compared to the commercial graphitic carbon. After 100 charge/discharge cycles, the fluorocarbon showed retentions of 91.3% and 97.5% in lithium (at 1C) and sodium (at 200 mA g -1 ) intercalation systems, respectively. The effects of carbonization temperature on the electrochemical properties of alkali metal ion storage were thoroughly investigated and documented. The specific capacities in lithium- and sodium-ion batteries were dependent on the fluorine content, indicating that the highly electronegative fluorine facilitates the insertion/extraction of lithium and sodium ions in rechargeable batteries.

  10. Conductive surface modification of cauliflower-like WO{sub 3} and its electrochemical properties for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Sukeun, E-mail: skyoon@kongju.ac.kr [Division of Advanced Materials Engineering, Kongju National University, Chungnam 330-717 (Korea, Republic of); Woo, Sang-Gil [Advanced Batteries Research Center, Korea Electronics Technology Institute, Gyeonggi 463-816 (Korea, Republic of); Jung, Kyu-Nam [Energy Efficiency and Materials Research Division, Korea Institute of Energy Research, Daejeon 305-343 (Korea, Republic of); Song, Huesup, E-mail: hssong@kongju.ac.kr [Division of Advanced Materials Engineering, Kongju National University, Chungnam 330-717 (Korea, Republic of)

    2014-11-15

    Highlights: • Synthesis of cauliflower-like carbon-decorated WO{sub 3}. • Superior cyclability and rate capability for cauliflower-like carbon-decorated WO{sub 3}. • Electrochemical reaction behavior of cauliflower-like carbon-decorated WO{sub 3} with lithium. • In-situ XRD analysis during the first discharge–charge shows a complex reaction of intercalation and conversion of WO{sub 3}. - Abstract: Cauliflower-like WO{sub 3} was synthesized by a hydrothermal reaction without a surfactant, followed by firing, and was investigated as an anode material for lithium-ion battery applications. The scanning electron microscope (SEM) and transmission electron microscope (TEM) characterization indicated that WO{sub 3} nanorods had an aggregation framework and built a cauliflower morphology. With the objective of understanding the charge–discharge process within a voltage range of 0–3 V vs. Li{sup +}/Li, in situ X-ray diffraction was used and a complex reaction of intercalation and conversion of WO{sub 3} was revealed for the first time. The cauliflower-like WO{sub 3} after being decorated with carbon provides a high gravimetric capacity of >635 mA h/g (Li{sub 5.5}WO{sub 3}) with good cycling and a high rate capability when used as an anode in lithium-ion batteries. Based on our studies, we attribute the high electrochemical performance to the nanoscopic WO{sub 3} particles and a conductive carbon layer, which makes them a potential candidate for lithium-ion batteries.

  11. A new lithium-ion battery internal temperature on-line estimate method based on electrochemical impedance spectroscopy measurement

    Science.gov (United States)

    Zhu, J. G.; Sun, Z. C.; Wei, X. Z.; Dai, H. F.

    2015-01-01

    The power battery thermal management problem in EV (electric vehicle) and HEV (hybrid electric vehicle) has been widely discussed, and EIS (electrochemical impedance spectroscopy) is an effective experimental method to test and estimate the status of the battery. Firstly, an electrochemical-based impedance matrix analysis for lithium-ion battery is developed to describe the impedance response of electrochemical impedance spectroscopy. Then a method, based on electrochemical impedance spectroscopy measurement, has been proposed to estimate the internal temperature of power lithium-ion battery by analyzing the phase shift and magnitude of impedance at different ambient temperatures. Respectively, the SoC (state of charge) and temperature have different effects on the impedance characteristics of battery at various frequency ranges in the electrochemical impedance spectroscopy experimental study. Also the impedance spectrum affected by SoH (state of health) is discussed in the paper preliminary. Therefore, the excitation frequency selected to estimate the inner temperature is in the frequency range which is significantly influenced by temperature without the SoC and SoH. The intrinsic relationship between the phase shift and temperature is established under the chosen excitation frequency. And the magnitude of impedance related to temperature is studied in the paper. In practical applications, through obtaining the phase shift and magnitude of impedance, the inner temperature estimation could be achieved. Then the verification experiments are conduced to validate the estimate method. Finally, an estimate strategy and an on-line estimation system implementation scheme utilizing battery management system are presented to describe the engineering value.

  12. Low-crystallinity molybdenum sulfide nanosheets assembled on carbon nanotubes for long-life lithium storage: Unusual electrochemical behaviors and ascending capacities

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaodan, E-mail: xiaodan_li@yeah.net [State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China ElectricPower University, Beijing, 102206 (China); Wu, Gaoxiang, E-mail: wgxjimmy@126.com [State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China ElectricPower University, Beijing, 102206 (China); Chen, Jiewei, E-mail: kzscjw@126.com [State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China ElectricPower University, Beijing, 102206 (China); Li, Meicheng, E-mail: mcli@ncepu.edu.cn [State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China ElectricPower University, Beijing, 102206 (China); Chongqing Materials Research Institute, Chongqing 400707 (China); Li, Wei, E-mail: wei.li@inl.int [International Iberian Nanotechnology Laboratory (INL), Braga 4715-330 (Portugal); Wang, Tianyue, E-mail: 1355796015@qq.com [State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China ElectricPower University, Beijing, 102206 (China); Jiang, Bing, E-mail: BingJiang@ncepu.edu.cn [State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China ElectricPower University, Beijing, 102206 (China); He, Yue, E-mail: 947667748@qq.com [State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China ElectricPower University, Beijing, 102206 (China); Mai, Liqiang, E-mail: mlq518@whut.edu.cn [State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Wuhan 430070 (China)

    2017-01-15

    Highlights: • Low-crystallinity molybdenum sulfide coated on carbon nanotubes were synthesized. • This anode material has unusual electrochemical behaviors compared to typical MoS{sub 2}. • It exhibits noticable ascending trends in capacity and superior rate performance. • The ascending performance can effectively extend the circulation life of batteries. - Abstract: Low-crystallinity molybdenum sulfide (LCMS, Mo:S = 1:2.75) nanosheets synthesized by a facile and low temperature solvothermal method is now reported. The as-prepared LCMS anode material is composited of MoS{sub 2} layers mixed with amorphous MoS{sub 3}, which leads to an unusual electrochemical process for lithium storage compared to typical MoS{sub 2} anode. The existence of MoS{sub 3} and Mo (VI) provide strong adsorption and binding sites for polar polysulphides, which compels abundant sulfur to turn into new-formed MoS{sub 3} rather than diffuse into electrolyte. To fully utilize this novel electrochemical process, LCMS is decorated on carbon nanotubes, obtaining well-dispersed CNTs@LCMS. As electrode material for lithium storage, CNTs@LCMS exhibits a noticable ascending trend in capacity from 820 mA h g{sup −1} to 1350 mA h g{sup −1} at 100 mA g{sup −1} during 130 cycles. The persistent ascending capacity is ascribed to the increasing lithium storage caused by new-formed MoS{sub 3}, combined with the reduced volume change benifiting from well-dispersed CNTs@LCMS. Furthermore, the ascending performance is proved to be able to effectively extend the circulation life (up to 200%) for lithium-ion batteries by mathematical modeling and calculation. Accordingly, the CNTs@LCMS composite is a promising anode material for long-life lithium-ion batteries.

  13. Performances of a lithium-carbon ``lithium ion``battery for electric powered vehicle; Performances d`un accumulateur au lithium-carbone ``Lithium Ion`` pour vehicule electrique

    Energy Technology Data Exchange (ETDEWEB)

    Broussely, M.; Planchat, J.P.; Rigobert, G.; Virey, D.; Sarre, G. [SAFT, Advanced and Industrial Battery Group, 86 - Poitiers (France)

    1996-12-31

    The lithium battery, also called `lithium-carbon` or `lithium ion`, is today the most promising candidate that can reach the expected minimum traction performances of electric powered vehicles. Thanks to a more than 20 years experience on lithium generators and to a specific research program on lithium batteries, the SAFT company has developed a 100 Ah electrochemical system, and full-scale prototypes have been manufactured for this application. These prototypes use the Li{sub x}NiO{sub 2} lithiated graphite electrochemical pair and were tested in terms of their electrical performances. Energy characteristics of 125 Wh/kg and 265 Wh/dm{sup 3} could be obtained. The possibility of supplying a power greater than 200 W/kg, even at low temperature (-10 deg. C) has been demonstrated with these elements. A full battery set of about 20 kWh was built and its evaluation is in progress. It comprises the electronic control systems for the optimum power management during charge and output. (J.S.) 9 refs.

  14. Performances of a lithium-carbon ``lithium ion``battery for electric powered vehicle; Performances d`un accumulateur au lithium-carbone ``Lithium Ion`` pour vehicule electrique

    Energy Technology Data Exchange (ETDEWEB)

    Broussely, M; Planchat, J P; Rigobert, G; Virey, D; Sarre, G [SAFT, Advanced and Industrial Battery Group, 86 - Poitiers (France)

    1997-12-31

    The lithium battery, also called `lithium-carbon` or `lithium ion`, is today the most promising candidate that can reach the expected minimum traction performances of electric powered vehicles. Thanks to a more than 20 years experience on lithium generators and to a specific research program on lithium batteries, the SAFT company has developed a 100 Ah electrochemical system, and full-scale prototypes have been manufactured for this application. These prototypes use the Li{sub x}NiO{sub 2} lithiated graphite electrochemical pair and were tested in terms of their electrical performances. Energy characteristics of 125 Wh/kg and 265 Wh/dm{sup 3} could be obtained. The possibility of supplying a power greater than 200 W/kg, even at low temperature (-10 deg. C) has been demonstrated with these elements. A full battery set of about 20 kWh was built and its evaluation is in progress. It comprises the electronic control systems for the optimum power management during charge and output. (J.S.) 9 refs.

  15. Electrolytes for Wide Operating Temperature Lithium-Ion Cells

    Science.gov (United States)

    Smart, Marshall C. (Inventor); Bugga, Ratnakumar V. (Inventor)

    2016-01-01

    Provided herein are electrolytes for lithium-ion electrochemical cells, electrochemical cells employing the electrolytes, methods of making the electrochemical cells and methods of using the electrochemical cells over a wide temperature range. Included are electrolyte compositions comprising a lithium salt, a cyclic carbonate, a non-cyclic carbonate, and a linear ester and optionally comprising one or more additives.

  16. Electrochemical Cell

    DEFF Research Database (Denmark)

    1999-01-01

    The invention relates to a rechargeable electrochemical cell comprising a negative electrode, an electrolyte and a positive electrode in which the positive electrode structure comprises a lithium cobalt manganese oxide of the composition Li¿2?Co¿y?Mn¿2-y?O¿4? where 0 ... for capacity losses in lithium ion cells and lithium-alloy cells....

  17. V-insertion in Li(Fe,Mn)FePO4

    Science.gov (United States)

    Wu, T.; Liu, J.; Sun, L.; Cong, L.; Xie, H.; Abdel-Ghany, A.; Mauger, A.; Julien, C. M.

    2018-04-01

    Insertion of 3% vanadium in LiMn1-yFeyPO4 has been investigated, with y = 0.2 corresponding to the highest manganese concentration before the stress/strain field degrades the electrochemical performance. V substitutes for Fe2+ in the trivalent state V3+. This substitution is accompanied with the formation of Fe vacancies while Mn remains in the Mn2+ valence state, leading to a composition LiMn0.8Fe0.2-0.045V0.03□0.015PO4 where □ is a Fe vacancy. The comparison between electrochemical properties of a pristine sample and a sample with 3 mol.% vanadium made of particles with the same morphology (spherical particles with the same dispersion 100-150 nm in size) and same carbon coating (same conductivity of the carbon layer) is reported. Although the vanadium is in the V3+ state at open circuit voltage (2.6 V) before cycling, a reversible V3+/V2+ is observed when the potential of the half-cell is lowered below the redox potential of 1.8 V vs Li+/Li, due to Li-vacancies. The V-insertion improves the electrochemical properties, due to a synergetic effect of an increase of the lithium diffusion coefficient by a factor two and an increase of the electric conductivity at any Li-concentration during the cycling process, in contradiction with prior claims that attributed the increase of conductivity to V-based impurities.

  18. Structural and Electrochemical Study of Vanadium-Doped TiO2 Ramsdellite with Superior Lithium Storage Properties for Lithium-Ion Batteries.

    Science.gov (United States)

    Pérez-Flores, Juan Carlos; Hoelzel, Markus; García-Alvarado, Flaviano; Kuhn, Alois

    2016-04-04

    Titanium-oxide-based materials are considered attractive and safe alternatives to carbonaceous anodes in Li-ion batteries. In particular, the ramsdellite form TiO2 (R) is known for its superior lithium-storage ability as the bulk material when compared with other titanates. In this work, we prepared V-doped lithium titanate ramsdellites with the formula Li0.5 Ti1-x Vx O2 (0≤x≤0.5) by a conventional solid-state reaction. The lithium-free Ti1-x Vx O2 compounds, in which the ramsdellite framework remains virtually unaltered, are easily obtained by a simple aqueous oxidation/ion-extraction process. Neutron powder diffraction is used to locate the Li channel site in Li0.5 Ti1-x Vx O2 compounds and to follow the lithium extraction by difference-Fourier maps. Previously delithiated Ti1-x Vx O2 ramsdellites are able to insert up to 0.8 Li(+) per transition-metal atom. The initial gravimetric capacities of 270 mAh g(-1) with good cycle stability under constant current discharge conditions are among the highest reported for bulk TiO2 -related intercalation compounds for the threshold of one e(-) per formula unit. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Ion-exchange synthesis and improved Li insertion property of lithiated H2Ti12O25 as a negative electrode material for lithium-ion batteries

    Directory of Open Access Journals (Sweden)

    Kunimitsu Kataoka

    2016-03-01

    Full Text Available We successfully prepared the lithiated H2Ti12O25 sample by the H+/Li+ ion exchange synthetic technique in the molten LiNO3 at 270 °C using H2Ti12O25 as a starting compound. Chemical composition of the obtained lithiated H2Ti12O25 sample was determined to be H1.05Li0.35Ti12O25-δ having δ = 0.3 by ICP-AES and DTA-TG analyses. The H+/Li+ ion exchange was also confirmed by powder XRD, 1H-MAS NMR, and 7Li-MAS NMR measurements. Electrochemical Li insertion and extraction measurements revealed that the initial coulombic efficiency was improved from 88% in H2Ti12O25 to 93% in the lithiated H2Ti12O25 sample. In addition, superior capacity retention properties for the charge and discharge cycling performance and good charge rate capability of the present lithiated H2Ti12O25 were confirmed in the electrochemical measurements. Accordingly, the lithiated H2Ti12O25 is suggested to be one of the promising high-voltage and high-capacity oxide negative electrodes in advanced lithium-ion batteries.

  20. Preparation of lithium indium oxide via a rheological phase route and its electrochemical characteristics in LiOH and Li{sub 2}SO{sub 4} solutions

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Guo-Qing [Department of Chemistry and Environment Science of Yangtze Normal University, 408100 Chongqing (China); College of Chemistry and Chemical Engineering of Chongqing University, Chongqing 400030 (China); Zhang, Sheng-Tao [College of Chemistry and Chemical Engineering of Chongqing University, Chongqing 400030 (China); Wu, Xing-Fa [Department of Chemistry and Environment Science of Yangtze Normal University, 408100 Chongqing (China)

    2010-01-15

    Submicrometer-sized lithium indium oxide (LiInO{sub 2}) powder via a rheological phase method using trilithium citrate tetra hydrate (C{sub 6}H{sub 5}Li{sub 3}O{sub 7} . 4H{sub 2}O) and indium oxide (In{sub 2}O{sub 3}) has been prepared in this work for the first time. The optimal pyrolyzing temperature range to prepare crystalline LiInO{sub 2} is between 650 and 900 C, which was confirmed by thermal gravimetric and differential thermogravimetric analysis of the precursor and X-ray diffraction analysis. The pure phase LiInO{sub 2} sample obtained has a uniform particle morphology and submicrosize, which was observed by scanning electron microscopy. The electrochemical studies show that a new pair of cathodic and anodic peaks at 0.23 and 0.38 V (vs. saturated calomel electrode) was obviously observed from the cyclic voltammetry curve of LiInO{sub 2} in 1 M LiOH solution, indicating a battery characteristic of the material in this electrolyte. While in 1 M Li{sub 2}SO{sub 4} solution, the sample presents a supercapacitive characteristic within the same potential range. The reasons for different electrochemical behaviors in these two electrolytes can be attributed to the fact that the reaction of lithium ion insertion/extraction into/out of a LiInO{sub 2} electrode takes place in the bulk material in LiOH electrolyte solution, whereas it takes place on the electrode/electrolyte interface for Li{sub 2}SO{sub 4} electrolyte case. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  1. Electrodeposition of high-density lithium vanadate nanowires for lithium-ion battery

    Science.gov (United States)

    Hua, Kang; Li, Xiujuan; Fang, Dong; Yi, Jianhong; Bao, Rui; Luo, Zhiping

    2018-07-01

    Lithium vanadate nanowires have been electrodeposited onto a titanium (Ti) foil by a direct current electrodeposition without template. The morphology, crystal structure, and the effects of deposition voltage, temperature and time on the prepared samples were tested and presented. The as-prepared lithium vanadate nanowires/Ti composite can be used as electrode for lithium-ion battery. Electrochemical measurements showed that the electrode displayed a specific discharge capacitance as high as 235.1 mAh g-1 after 100 cycles at a current density of 30 mA g-1. This research provides a new pathway to explore high tap density vanadates nanowires on metals with enhanced electrochemical performance.

  2. Electrochemical characteristics of nanostructured silicon anodes for lithium-ion batteries

    International Nuclear Information System (INIS)

    Astrova, E. V.; Li, G. V.; Rumyantsev, A. M.; Zhdanov, V. V.

    2016-01-01

    High-aspect periodic structures with thin vertical walls are studied as regards their applicability as negative electrodes of lithium-ion batteries. The nanostructures are fabricated from single-crystal silicon using photolithography, electrochemical anodization, and subsequent anisotropic shaping. The capacity per unit of the visible surface area of the electrode and the specific internal surface area are compared for structures of varied architecture: 1D (wires), 2D (zigzag walls), and 3D structures (walls forming a grid). Main attention is given to testing the endurance of anodes based on zigzag and grid structures, performed by galvanostatic cycling in half-cells with a lithium counter electrode. The influence exerted by the geometric parameters of the structures and by the testing mode on the degradation rate is determined. It is shown that the limiting factor of the lithiation and delithiation processes is diffusion. The endurance of an electrode dramatically increases when the charging capacity is limited to ∼1000 mA h/g. In this case, nanostructures with 300-nm-thick walls, which underwent cyclic testing at a rate of 0.36C, retain a constant discharge capacity and a Coulomb efficiency close to 100% for more than 1000 cycles.

  3. Electrochemical characteristics of nanostructured silicon anodes for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Astrova, E. V., E-mail: east@mail.ioffe.ru; Li, G. V.; Rumyantsev, A. M.; Zhdanov, V. V. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation)

    2016-02-15

    High-aspect periodic structures with thin vertical walls are studied as regards their applicability as negative electrodes of lithium-ion batteries. The nanostructures are fabricated from single-crystal silicon using photolithography, electrochemical anodization, and subsequent anisotropic shaping. The capacity per unit of the visible surface area of the electrode and the specific internal surface area are compared for structures of varied architecture: 1D (wires), 2D (zigzag walls), and 3D structures (walls forming a grid). Main attention is given to testing the endurance of anodes based on zigzag and grid structures, performed by galvanostatic cycling in half-cells with a lithium counter electrode. The influence exerted by the geometric parameters of the structures and by the testing mode on the degradation rate is determined. It is shown that the limiting factor of the lithiation and delithiation processes is diffusion. The endurance of an electrode dramatically increases when the charging capacity is limited to ∼1000 mA h/g. In this case, nanostructures with 300-nm-thick walls, which underwent cyclic testing at a rate of 0.36C, retain a constant discharge capacity and a Coulomb efficiency close to 100% for more than 1000 cycles.

  4. Electrochemical reaction mechanisms under various charge-discharge operating conditions for Li1.2Ni0.13Mn0.54Co0.13O2 in a lithium-ion battery

    Science.gov (United States)

    Konishi, Hiroaki; Hirano, Tatsumi; Takamatsu, Daiko; Gunji, Akira; Feng, Xiaoliang; Furutsuki, Sho; Okumura, Takefumi; Terada, Shohei; Tamura, Kazuhisa

    2018-06-01

    The potential in each state of charge (SOC) during charging of Li1.2Ni0.13Mn0.54Co0.13O2 is higher than that during discharging. In other words, the potential hysteresis occurs between charging and discharging. Furthermore, the potential in each SOC changes according to the charge-discharge operating conditions, indicating that the charge-discharge reaction mechanism is also affected. To clarify the effect of charge-discharge operating conditions on the electrochemical reaction, Li1.2Ni0.13Mn0.54Co0.13O2 was charged and discharged under various charge-discharge operating ranges, and open-circuit potential (OCP), crystal structure, and oxidation states of the transition metals were evaluated by electrochemical measurement, X-ray diffraction (XRD), and X-ray absorption fine structure (XAFS). These results indicate that OCP, lattice parameters, and oxidation states of the transition metals of Li1.2Ni0.13Mn0.54Co0.13O2 in each SOC are not constant. The XRD results indicate that two phases, namely, LiNi0.33Mn0.33Co0.33O2-like and Li2MnO3-like, exist in Li1.2Ni0.13Mn0.54Co0.13O2. For the LiNi0.33Mn0.33Co0.33O2-like phase, the relationship between OCP, lattice parameters, and oxidation states of the transition metals in each SOC is not affected by the charge-discharge operating conditions, indicating that extraction and insertion of lithium ions for the LiNi0.33Mn0.33Co0.33O2-like phase progresses at almost the same potential. Although the extraction and insertion of lithium ions for the Li2MnO3-like phase progresses at almost the same potential in the low-SOC region, the OCP and lattice parameter in each SOC in the high-SOC region are not constant. Therefore, the extraction of lithium ions from the Li2MnO3-like phase in the high-SOC region causes the potential hysteresis of Li1.2Ni0.13Mn0.54Co0.13O2.

  5. Fabrication of lithium titanate/graphene composites with high rate capability as electrode materials for hybrid electrochemical supercapacitors

    International Nuclear Information System (INIS)

    Xue, Rong; Yan, Jingwang; Jiang, Liang; Yi, Baolian

    2015-01-01

    A lithium titanate (Li 4 Ti 5 O 12 )/graphene composite (LTO/graphene) is fabricated with a one-pot sol–gel method. Graphite oxide is dispersed in an aqueous solution of lithium acetate and tetrabutyl titanate followed by heat treatment in H 2 /Ar. The LTO/graphene composite with reduced aggregation and improved homogeneity is investigated as an anode material for electrochemical capacitors. Electron transport is improved by the conductive graphene network in the insulating Li 4 Ti 5 O 12 particles. The charge transfer resistance at the particle/electrolyte interface is reduced from 83.1 Ω to 55.4 Ω. The specific capacity of LTO/graphene composite is 126 mAh g −1 at 20C. The energy density and power density of a hybrid electrochemical supercapacitor with a LTO/graphene negative electrode and an activated carbon positive electrode are 120.8 Wh kg −1 and 1.5 kW kg −1 , respectively, which is comparable to that of conventional electrochemical double layer capacitors (EDLCs). The LTO/graphene composite fabricated by the one-pot sol–gel method is a promising anode material for hybrid electrochemical supercapacitors. - Highlights: • A Li 4 Ti 5 O 12 /graphene composite was fabricated with a one-pot sol–gel method. • The Li 4 Ti 5 O 12 /graphene composite showed a reduced aggregation and an improved homogeneity. • The Li 4 Ti 5 O 12 /graphene based hybrid supercapacitor exhibited higher energy and power densities

  6. Low Li+ Insertion Barrier Carbon for High Energy Efficient Lithium-Ion Capacitor.

    Science.gov (United States)

    Lee, Wee Siang Vincent; Huang, Xiaolei; Tan, Teck Leong; Xue, Jun Min

    2018-01-17

    Lithium-ion capacitor (LIC) is an attractive energy-storage device (ESD) that promises high energy density at moderate power density. However, the key challenge in its design is the low energy efficient negative electrode, which barred the realization of such research system in fulfilling the current ESD technological inadequacy due to its poor overall energy efficiency. Large voltage hysteresis is the main issue behind high energy density alloying/conversion-type materials, which reduces the electrode energy efficiency. Insertion-type material though averted in most research due to the low capacity remains to be highly favorable in commercial application due to its lower voltage hysteresis. To further reduce voltage hysteresis and increase capacity, amorphous carbon with wider interlayer spacing has been demonstrated in the simulation result to significantly reduce Li + insertion barrier. Hence, by employing such amorphous carbon, together with disordered carbon positive electrode, a high energy efficient LIC with round-trip energy efficiency of 84.3% with a maximum energy density of 133 Wh kg -1 at low power density of 210 W kg -1 can be achieved.

  7. Lithium intercalation in sputter deposited antimony-doped tin oxide thin films: Evidence from electrochemical and optical measurements

    Energy Technology Data Exchange (ETDEWEB)

    Montero, J., E-mail: jose.montero@angstrom.uu.se; Granqvist, C. G.; Niklasson, G. A. [Department of Engineering Sciences, The A°ngström Laboratory, Uppsala University, P.O. Box 534, SE-751 21 Uppsala (Sweden); Guillén, C.; Herrero, J. [Department of Energy, Ciemat, Avda. Complutense 40, Ed. 42, E-28040 Madrid (Spain)

    2014-04-21

    Transparent conducting oxides are used as transparent electrical contacts in a variety of applications, including in electrochromic smart windows. In the present work, we performed a study of transparent conducting antimony-doped tin oxide (ATO) thin films by chronopotentiometry in a Li{sup +}-containing electrolyte. The open circuit potential vs. Li was used to investigate ATO band lineups, such as those of the Fermi level and the ionization potential, as well as the dependence of these lineups on the preparation conditions for ATO. Evidence was found for Li{sup +} intercalation when a current pulse was set in a way so as to drive ions from the electrolyte into the ATO lattice. Galvanostatic intermittent titration was then applied to determine the lithium diffusion coefficient within the ATO lattice. The electrochemical density of states of the conducting oxide was studied by means of the transient voltage recorded during the chronopotentiometry experiments. These measurements were possible because, as Li{sup +} intercalation took place, charge compensating electrons filled the lowest part of the conduction band in ATO. Furthermore, the charge insertion modified the optical properties of ATO according to the Drude model.

  8. Anode behaviors of aluminum antimony synthesized by mechanical alloying for lithium secondary battery

    International Nuclear Information System (INIS)

    Honda, H.; Sakaguchi, H.; Fukuda, Y.; Esaka, T.

    2003-01-01

    AlSb was synthesized as an anode active material for lithium secondary battery using mechanical alloying (MA). Electrochemical performance was examined on the electrodes of AlSb synthesized with different MA time. The first charge (lithium-insertion) capacity of the AlSb electrodes decreased with increasing the MA time. The discharge capacity on repeating charge-discharge cycle, however, did not show the same dependence. The electrode, consisting of the 20 h MA sample exhibited the longest charge-discharge life cycle, suggesting that there is the optimum degree of internal energy derived from the strain and/or the amorphization due to mechanical alloying. These results were evaluated using ex situ X-ray diffraction and differential scanning calorimetry

  9. Lanthanum Nitrate As Electrolyte Additive To Stabilize the Surface Morphology of Lithium Anode for Lithium-Sulfur Battery.

    Science.gov (United States)

    Liu, Sheng; Li, Guo-Ran; Gao, Xue-Ping

    2016-03-01

    Lithium-sulfur (Li-S) battery is regarded as one of the most promising candidates beyond conventional lithium ion batteries. However, the instability of the metallic lithium anode during lithium electrochemical dissolution/deposition is still a major barrier for the practical application of Li-S battery. In this work, lanthanum nitrate, as electrolyte additive, is introduced into Li-S battery to stabilize the surface of lithium anode. By introducing lanthanum nitrate into electrolyte, a composite passivation film of lanthanum/lithium sulfides can be formed on metallic lithium anode, which is beneficial to decrease the reducibility of metallic lithium and slow down the electrochemical dissolution/deposition reaction on lithium anode for stabilizing the surface morphology of metallic Li anode in lithium-sulfur battery. Meanwhile, the cycle stability of the fabricated Li-S cell is improved by introducing lanthanum nitrate into electrolyte. Apparently, lanthanum nitrate is an effective additive for the protection of lithium anode and the cycling stability of Li-S battery.

  10. Preparation and characterization of a new carbonaceous material for electrochemical systems

    Directory of Open Access Journals (Sweden)

    ZI JI LIN

    2010-02-01

    Full Text Available A new carbonaceous material was successfully prepared by the py-rolysis of scrap tire rubber at 600 °C under a nitrogen atmosphere. The physical characteristics of the prepared carbonaceous material were studied by scanning electron microscopy (SEM, X-ray powder diffraction (XRD and X-ray photoelectron spectroscopy (XPS. It was proved that the carbonaceous material had a disordered structure and spherical morphology with an average particle size about 100 nm. The prepared carbonaceous material was also used as electrodes in electrochemical systems to examine its electrochemical performances. It was demonstrated that it delivered a lithium insertion capacity of 658 mA h g-1 during the first cycle with a coulombic efficiency of 68 %. Cyclic voltammograms test results showed that a redox reaction occurred during the cycles. The chemical diffusion coefficient based on the impedance diagram was about 10-10 cm2 s-1. The pyrolytic carbonaceous material derived from scrap tire rubber is therefore considered to be a potential anode material in lithium secondary batteries or capacitors. Furthermore, it is advantageous for environmental protection.

  11. Cathode Materials for High Energy Density Lithium Batteries

    Directory of Open Access Journals (Sweden)

    Lefèvre G.

    2017-01-01

    Li2MnSiO4 has a large theoretical specific capacity (333 mAh/g through exchange of 2 lithium ions per formula unit. The thermal stability due to strong Si-O bonds makes LiMnSiO a very promising material for future energy storage in space applications. Preparation in inert atmosphere showed beneficial improvements of LMSO’s electrochemical properties. Nano-sizing and carbon coating have been effective ways to improve electronic conductivity and therefore electrochemical performance. Up to 1.66 Li per formula unit can be re-inserted in the 1st cycle. XRD analysis showed complete amorphization of Li2MnSiO4 after the 1st charge at 4.8 V with complete modification of the charge/discharge curves in the next cycles. Increasing the carbon coating ratio limits capacity loss during cycling but did not avoid amorphization. Finally influence of voltage window on structure stability was investigated. Careful choice of upper limit voltage has been showed to stabilize Li2MnSiO4 structure but for now is still limited to low Li+ insertion/extraction from the host material.

  12. Porous Co3O4 nanorods as anode for lithium-ion battery with excellent electrochemical performance

    International Nuclear Information System (INIS)

    Guo, Jinxue; Chen, Lei; Zhang, Xiao; Chen, Haoxin

    2014-01-01

    In this manuscript, porous Co 3 O 4 nanorods are prepared through a two-step approach which is composed of hydrothermal process and heating treatment as high performance anode for lithium-ion battery. Benefiting from the porous structure and 1-dimensional features, the product becomes robust and exhibits high reversible capability, good cycling performance, and excellent rate performance. - Graphical abstract: 1D porous Co 3 O 4 nanostructure as anode for lithium-ion battery with excellent electrochemical performance. - Highlights: • A two-step route has been applied to prepare 1D porous Co 3 O 4 nanostructure. • Its porous feature facilitates the fast transport of electron and lithium ion. • Its porous structure endows it with capacities higher than its theoretical capacity. • 1D nanostructure can tolerate volume changes during lithation/delithiation cycles. • It exhibits high capacity, good cyclability and excellent rate performance

  13. Lithium insertion in nanostructured titanates

    NARCIS (Netherlands)

    Borghols, W.J.H.

    2010-01-01

    Upon nano-sizing of insertion compounds several significant changes in Li-insertion behavior have been observed for sizes below approximately 50 nm. Although the origins of the phenomena are interrelated, the changes can be divided in three main observations. (1) The formation of new phases, leading

  14. Synthesis of one-dimensional copper sulfide nanorods as high-performance anode in lithium ion batteries.

    Science.gov (United States)

    Li, Xue; He, Xinyi; Shi, Chunmei; Liu, Bo; Zhang, Yiyong; Wu, Shunqing; Zhu, Zizong; Zhao, Jinbao

    2014-12-01

    Nanorod-like CuS and Cu2 S have been fabricated by a hydrothermal approach without using any surfactant and template. The electrochemical behavior of CuS and Cu2 S nanorod anodes for lithium-ion batteries reveal that they exhibit stable lithium-ion insertion/extraction reversibility and outstanding rate capability. Both of the electrodes exhibit excellent capacity retentions irrespective of the rate used, even at a high current density of 3200 mA g(-1) . More than 370 mAh g(-1) can be retained for the CuS electrode and 260 mAh g(-1) for the Cu2 S electrode at the high current rate. After 100 cycles at 100 mA g(-1) , the obtained CuS and Cu2 S electrodes show discharge capacities of 472 and 313 mAh g(-1) with retentions of 92% and 96%, respectively. Together with the simplicity of fabrication and good electrochemical properties, CuS and Cu2 S nanorods are promising anode materials for practical use the next-generation lithium-ion batteries. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. In situ synthesis of α-MoO3/graphene composites as anode materials for lithium ion battery

    International Nuclear Information System (INIS)

    Liu, Chun-Ling; Wang, Yan; Zhang, Chen; Li, Xiao-Shan; Dong, Wen-Sheng

    2014-01-01

    The α-MoO 3 /graphene composites (MoO 3 /G) were prepared via an in situ hydrothermal synthesis. The composites were characterized using various characterization techniques including powder X-ray diffraction, transmission electron microscopy, scanning electron microscopy, X-ray photoelectron spectroscopy, and the electrochemical performance test. The results show that these MoO 3 /G composites exhibit high capacity and good cycle stability when used as the lithium-ion battery anode. Among all the samples, the MoO 3 /G-27 reveals the best electrochemical performance with an initial charge capacity of 977.7 mAh g −1 at a current density of 50 mA g −1 , the first coulombic efficiency of 69.5%. After eighty cycles the electrode still maintains a capacity of 869.2 mAh g −1 , giving high capacity retention of 88.9%. The good electrochemical performance of the composite anode is close related to its structure, in which the MoO 3 nanobelts are not only homogeneously anchored on the surface but also embedded in the interlayer of the graphene sheets; hence the volume change and aggregation of the MoO 3 nanobelts during lithium ion insertion/extraction process can be effectively hindered. On the other hand, graphene itself is an electronic conductor; the graphene and MoO 3 nanobelts connect closely, which offers large electrode/electrolyte contacting area, short path length for Li + transporting during lithium insertion and extraction. - Highlights: • The α-MoO 3 /graphene composites were prepared via an in situ hydrothermal synthesis. • The MoO 3 /G-27 anode delivers an initial reversible capacity of 977.7 mAh g −1 . • After 80 cycles it has a reversible capacity of 869.2 mAh g −1 at 50 mA g −1

  16. Electrochemical evaluation of the a carbon-paste electrode modified with spinel manganese(IV) oxide under flow conditions for amperometric determination of lithium

    International Nuclear Information System (INIS)

    Raymundo-Pereira, Paulo A.; Martin, Cibely S.; Bergamini, Marcio F.; Bocchi, Nerilso; Teixeira, Marcos F.S.

    2011-01-01

    The participation of cations in redox reactions of manganese oxides provides an opportunity for development of chemical sensors for non-electroactive ions. This paper describes the amperometric determination of lithium ions using carbon-paste electrode modified with spinel manganese(IV) oxide under flow conditions. Systematic investigations were made to optimize the experimental parameters for lithium sensor by flow injection analysis. The detection was based on the measurement of anodic current generated by oxidation of Mn(III) to Mn(IV) at the surface of the electrode and consequently the lithium ions extraction into the spinel structure. An operating potential of 0.50 V (vs. Ag/AgCl/3 KCl mol/L) was exploited for amperometric monitoring. The amperometric signal was linearly dependent on the lithium ions concentration over the range 4.0 x 10 -5 to 1.0 x 10 -3 mol L -1 . The equilibrium constant of insertion/extraction of the lithium ion in the spinel structure, apparent Gibbs energy of insertion, and surface coverage of the electrode with manganese oxide, were calculated by peak charge (Q) in different concentration under flow conditions. Considering selectivity, the peak charge of the sensor was found to be linearly dependent on the ionic radius of the alkaline and earth-alkaline cations.

  17. A Core-Shell Fe/Fe2 O3 Nanowire as a High-Performance Anode Material for Lithium-Ion Batteries.

    Science.gov (United States)

    Na, Zhaolin; Huang, Gang; Liang, Fei; Yin, Dongming; Wang, Limin

    2016-08-16

    The preparation of novel one-dimensional core-shell Fe/Fe2 O3 nanowires as anodes for high-performance lithium-ion batteries (LIBs) is reported. The nanowires are prepared in a facile synthetic process in aqueous solution under ambient conditions with subsequent annealing treatment that could tune the capacity for lithium storage. When this hybrid is used as an anode material for LIBs, the outer Fe2 O3 shell can act as an electrochemically active material to store and release lithium ions, whereas the highly conductive and inactive Fe core functions as nothing more than an efficient electrical conducting pathway and a remarkable buffer to tolerate volume changes of the electrode materials during the insertion and extraction of lithium ions. The core-shell Fe/Fe2 O3 nanowire maintains an excellent reversible capacity of over 767 mA h g(-1) at 500 mA g(-1) after 200 cycles with a high average Coulombic efficiency of 98.6 %. Even at 2000 mA g(-1) , a stable capacity as high as 538 mA h g(-1) could be obtained. The unique composition and nanostructure of this electrode material contribute to this enhanced electrochemical performance. Due to the ease of large-scale fabrication and superior electrochemical performance, these hybrid nanowires are promising anode materials for the next generation of high-performance LIBs. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. A comparative study on electrochemical performances of the electrodes with different nanocarbon conductive additives for lithium ion batteries

    International Nuclear Information System (INIS)

    Chen, Taiqiang; Pan, Likun; Liu, Xinjuan; Sun, Zhuo

    2013-01-01

    Three nanocarbon materials (0 D acetylene black (AB), 1 D carbon nanotubes (CNTs) and 2 D reduced graphene oxide (RGO)) were used as conductive additives (CAs) in the mesocarbon microbead anodes for lithium ion batteries. The electrochemical performances of the electrodes were investigated. The results show that the CAs have a significant impact on the electrode performance because they can influence the electron conduction and lithium ion transportation within the electrode. The electrode with RGO achieves a maximum capacity of 387 mAh g −1 after 50 cycles at a current density of 50 mA g −1 , much higher than those of the electrodes with AB (334 mAh g −1 ) and CNTs (319 mAh g −1 ). The improvement should be mainly ascribed to the “plane-to-point” conducting network formed in the electrode with 2 D RGO which can favor the electron conduction and enhance the lithium ion transportation. - Highlights: • Three carbon materials were used as additives in the electrodes of Li ion battery. • The electrochemical performances of the electrodes were comparatively investigated. • The carbon additives have a significant impact on the electrode performance. • RGO additive acts as a bridge to form a “plane-to-point” conducting network. • The electrode with RGO exhibits better performance than those with other additives

  19. Fabrication of lithium titanate/graphene composites with high rate capability as electrode materials for hybrid electrochemical supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Rong, E-mail: xuerongsmile@qq.com; Yan, Jingwang, E-mail: yanjw@dicp.ac.cn; Jiang, Liang, E-mail: jiangliang@dicp.ac.cn; Yi, Baolian, E-mail: blyi@dicp.ac.cn

    2015-06-15

    A lithium titanate (Li{sub 4}Ti{sub 5}O{sub 12})/graphene composite (LTO/graphene) is fabricated with a one-pot sol–gel method. Graphite oxide is dispersed in an aqueous solution of lithium acetate and tetrabutyl titanate followed by heat treatment in H{sub 2}/Ar. The LTO/graphene composite with reduced aggregation and improved homogeneity is investigated as an anode material for electrochemical capacitors. Electron transport is improved by the conductive graphene network in the insulating Li{sub 4}Ti{sub 5}O{sub 12} particles. The charge transfer resistance at the particle/electrolyte interface is reduced from 83.1 Ω to 55.4 Ω. The specific capacity of LTO/graphene composite is 126 mAh g{sup −1} at 20C. The energy density and power density of a hybrid electrochemical supercapacitor with a LTO/graphene negative electrode and an activated carbon positive electrode are 120.8 Wh kg{sup −1} and 1.5 kW kg{sup −1}, respectively, which is comparable to that of conventional electrochemical double layer capacitors (EDLCs). The LTO/graphene composite fabricated by the one-pot sol–gel method is a promising anode material for hybrid electrochemical supercapacitors. - Highlights: • A Li{sub 4}Ti{sub 5}O{sub 12}/graphene composite was fabricated with a one-pot sol–gel method. • The Li{sub 4}Ti{sub 5}O{sub 12}/graphene composite showed a reduced aggregation and an improved homogeneity. • The Li{sub 4}Ti{sub 5}O{sub 12}/graphene based hybrid supercapacitor exhibited higher energy and power densities.

  20. Freeze-drying synthesis of three-dimensional porous LiFePO4 modified with well-dispersed nitrogen-doped carbon nanotubes for high-performance lithium-ion batteries

    International Nuclear Information System (INIS)

    Tu, Xiaofeng; Zhou, Yingke; Song, Yijie

    2017-01-01

    Highlights: • Three-dimensional porous LiFePO 4 /N-CNTs is synthesized by a freeze-drying method. • The N-CNTs conductive network enhances the electron transport within the LiFePO 4 electrode. • The continuous pores accelerate the diffusion of lithium ions. • LiFePO 4 /N-CNTs demonstrates an excellent electrochemical Li-insertion performance. - Abstract: The three-dimensional porous LiFePO 4 modified with uniformly dispersed nitrogen-doped carbon nanotubes has been successfully prepared by a freeze-drying method. The morphology and structure of the porous composites are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), and the electrochemical performances are evaluated using the constant current charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy. The nitrogen-doped carbon nanotubes are uniformly dispersed inside the porous LiFePO 4 to construct a superior three-dimensional conductive network, which remarkably increases the electronic conductivity and accelerates the diffusion of lithium ion. The porous composite displays high specific capacity, good rate capability and excellent cycling stability, rendering it a promising positive electrode material for high-performance lithium-ion batteries.

  1. Novel iron-cobalt derivatised lithium iron phosphate nanocomposite for lithium ion battery cathode

    CSIR Research Space (South Africa)

    Ikpo, CO

    2013-01-01

    Full Text Available Described herein is the electrochemical study conducted on lithium ion battery cathode material consisting of composite of lithium iron phosphate (LiFePO(sub4), iron-cobalt derivatised carbon nanotubes (FeCo-CNT) and polyaniline (PA) nanomaterials...

  2. Investigations of the Electrochemical Stability of Aqueous Electrolytes for Lithium Battery Applications

    KAUST Repository

    Wessells, Colin

    2010-01-01

    The electrolytic stability windows of several aqueous electrolytes were investigated by a constant current method. The electrode potential range depended upon the value of the imposed current. The magnitude of this behavior varied with the salt solution, its concentration, and pH of the electrolyte. At a leakage current density of 50 μA/cm2, a 5 M solution of LiNO3 had an electrolytic window of 2.3 V, spanning from -0.55 to 1.75 V with respect to the standard hydrogen electrode. These results demonstrate the feasibility of operating lithium batteries at voltages appreciably above the theoretical decomposition voltage of water. © 2010 The Electrochemical Society.

  3. Secondary lithium solid polymer electrolyte cells

    International Nuclear Information System (INIS)

    Fix, K.A.; Sammells, A.F.

    1988-01-01

    A strategy for developing morphologically invariant lithium/solid polymer electrolyte interface is being investigated via the use of lithium intercalated electrodes. Emphasis is being placed upon the rutile material Li/sub x/WO/sub 2/ 0.1 < x < 1.0. An absence of shape change at this interface is expected to result in both long cycle life electrochemical cells and the simultaneous maintenance of small interelectrode spacing so that low IR losses can be maintained. During fabrication of cells investigated here both electrochemical and chemical lithium intercalation of WO/sub 2/ was pursued. In the case of larger WO/sub 2/ electrodes initially prepared for fully discharged state cells, electrochemical intercalation during cell charge was found to require significant time, and the reproducible achievement of complete uniform intercalation across the negative electrode became an issue. Emphasis was consequently placed upon cells fabricated using Li/sub x/WO/sub 2/ electrodes initially chemically intercalated by lithium prior to cell assembly. Previous work has demonstrated direct lithium intercalation of metal dichalcogenides using n-BuLi. Lithium activity in n-BuLi is, however, insufficient to achieve lithium intercalation of WO/sub 2//sup 4/. However, recent work has shown that WO/sub 2/ can be directly lithium intercalated upon immersion in lithium naphthalide. Li/sub x/WO/sub 2/ electrodes prepared in this work were intercalated using lithium naphthalide (0.8M) in 2MeTHF. Lithium intercalation was found to readily occur at room temperature, being initially rapid and slowing as bulk intercalation within the electrode proceeded. For electrodes intercalated in this manner, a relationship was identified between the degree of lithium intercalation and initial open-circuit potential in liquid non-aqueous electrolyte

  4. Electrochemical and safety characteristics of TiP2O7–graphene nanocomposite anode for rechargeable lithium-ion batteries

    International Nuclear Information System (INIS)

    Rai, Alok Kumar; Gim, Jihyeon; Song, Jinju; Mathew, Vinod; Anh, Ly Tuan; Kim, Jaekook

    2012-01-01

    This paper reports a co-precipitation synthesis of TiP 2 O 7 –graphene (10 wt%) nanocomposite and pure TiP 2 O 7 nanoparticles for the use as an advanced anode material for high performance lithium-ion batteries. The structure and morphology of the compounds are characterized by powder X-ray diffraction, field-emission scanning electron microscopy and field-emission transmission electron microscopy techniques. The electrochemical performances were evaluated in coin type Li-ion test cells. This TiP 2 O 7 –graphene nanocomposite displayed superior Li-ion battery performance with a large reversible capacity, excellent cyclic performance and good rate capability at a current density of 0.1 mA cm −2 . At an elevated current density of 6.4 mA cm −2 , the nanocomposite anode delivered a capacity of 98.4 mAh g −1 , which is much higher than that of pure TiP 2 O 7 (0.56 mAh g −1 ). The impressive electrochemical performance of the nanocomposite was ascribed to the synergistic effect of the high surface area nanoparticles in conjunction with the good electronic conductivity of graphene. The graphene nanosheets not only provide an electronically conducting network, but also tend to prevent the aggregation of the high surface area TiP 2 O 7 nanoparticles. Further, the graphene nanosheets can act as buffer layers to accommodate the volume change during the Li-ion insertion/extraction processes in the TiP 2 O 7 nanoparticles.

  5. Hierarchical structured graphene/metal oxide/porous carbon composites as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Guo, Rong; Yue, Wenbo; Ren, Yu; Zhou, Wuzong

    2016-01-01

    Highlights: • CeO 2 and Co 3 O 4 nanoparticles display different behavior within CMK-3. • CMK-3-CeO 2 and Co 3 O 4 show various electrochemical properties • CMK-3-CeO 2 and Co 3 O 4 are further wrapped by graphene nanosheets. • Graphene-encapsulated composites show better electrochemical performances. - Abstract: As a novel anode material for lithium-ion batteries, CeO 2 displays imperceptible volumetric and morphological changes during the lithium insertion and extraction processes, and thereby exhibits good cycling stability. However, the low theoretical capacity and poor electronic conductivity of CeO 2 hinder its practical application. In contrast, Co 3 O 4 possesses high theoretical capacity, but undergoes huge volume change during cycling. To overcome these issues, CeO 2 and Co 3 O 4 nanoparticles are formed inside the pores of CMK-3 and display various electrochemical behaviors due to the different morphological structures of CeO 2 and Co 3 O 4 within CMK-3. Moreover, the graphene/metal oxide/CMK-3 composites with a hierarchical structure are then prepared and exhibit better electrochemical performances than metal oxides with or without CMK-3. This novel synthesis strategy is hopefully employed in the electrode materials design for Li-ion batteries or other energy conversion and storage devices.

  6. Synthesis and electrochemical performances of amorphous carbon-coated Sn Sb particles as anode material for lithium-ion batteries

    Science.gov (United States)

    Wang, Zhong; Tian, Wenhuai; Liu, Xiaohe; Yang, Rong; Li, Xingguo

    2007-12-01

    The amorphous carbon coating on the Sn-Sb particles was prepared from aqueous glucose solutions using a hydrothermal method. Because the outer layer carbon of composite materials is loose cotton-like and porous-like, it can accommodate the expansion and contraction of active materials to maintain the stability of the structure, and hinder effectively the aggregation of nano-sized alloy particles. The as-prepared composite materials show much improved electrochemical performances as anode materials for lithium-ion batteries compared with Sn-Sb alloy and carbon alone. This amorphous carbon-coated Sn-Sb particle is extremely promising anode materials for lithium secondary batteries and has a high potentiality in the future use.

  7. Preparation and electrochemical performance of bramble-like ZnO array as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Yan, Junfeng; Wang, Gang; Wang, Hui; Zhang, Zhiyong; Ruan, Xiongfei; Zhao, Wu; Yun, Jiangni; Xu, Manzhang

    2015-01-01

    A bramble-like ZnO array with a special three-dimensional (3D) nanostructure was successfully fabricated on Zn foil through a facile two-step hydrothermal process. A possible growth mechanism of the bramble-like ZnO array was proposed. In the first step of hydrothermal process, the crystal nucleus of Zn(OH) 4 2− generated by the zinc atoms and OH − ions fold together preferentially along the positive polar (0001) to form the needle-like ZnO array. In the second step of hydrothermal process, the crystal nuclei of Zn(OH) 4 2− adjust their posture to keep their c-axes vertical to the perching sites due to the sufficient environmental force and further grow preferentially along the (0001) direction so as to form bramble-like ZnO array. The electrochemical properties of the needle- and bramble-like ZnO arrays as anode materials for lithium-ion batteries were investigated and compared. The results show that the bramble-like ZnO material exhibits much better lithium storage properties than the needle-like ZnO sample. Reasons for the enhanced electrochemical performance of the bramble-like ZnO material were investigated

  8. Synthesis and Electrochemical Studies of ReO3 Type Phase Nb3O7F

    Directory of Open Access Journals (Sweden)

    D. Saritha

    2018-04-01

    Full Text Available In latest era, explore for alternative materials to carbonaceous negative electrodes working at higher potential in lithium ion batteries is given enormous significance to avoid lithium plating and electrolyte decomposition. Niobium based oxides show enhanced results as choice to carbonaceous anodes and also Nb5+/4+ redox couple working at approximately 1.5V vs. lithium.The redox potential of the niobium metal ion (~1.5V and the structure of Nb3O7F encourage us lithium insertion studies. Nb3O7F compound has been synthesized through a simple solid state method to explore as anode material. A structural and electrochemical property of this compound is studied in detail.The charge-discharge curves are obtained galvanostatically at C/5 rate. In first discharge step, 5.3 Li can be inserted into four step process between 3.0 – 1.0 V with a specific capacity of 350 mAhg-1. Four plateaus are observed at 1.65, 1.3,1.2 and 1.1V. During charge 1.3 Li can be extracted with an irreversible capacity loss. The total first-charge capacity is 86 mAhg-1 corresponding to the extraction of 1.3 Li. These cells show a reversible capacity 86 mAhg-1 after 25 cycles. The detailed results will be described and discussed.

  9. Facile and Scalable Synthesis of Zn3V2O7(OH)2·2H2O Microflowers as a High-Performance Anode for Lithium-Ion Batteries.

    Science.gov (United States)

    Yan, Haowu; Luo, Yanzhu; Xu, Xu; He, Liang; Tan, Jian; Li, Zhaohuai; Hong, Xufeng; He, Pan; Mai, Liqiang

    2017-08-23

    The employment of nanomaterials and nanotechnologies has been widely acknowledged as an effective strategy to enhance the electrochemical performance of lithium-ion batteries (LIBs). However, how to produce nanomaterials effectively on a large scale remains a challenge. Here, the highly crystallized Zn 3 V 2 O 7 (OH) 2 ·2H 2 O is synthesized through a simple liquid phase method at room temperature in a large scale, which is easily realized in industry. Through suppressing the reaction dynamics with ethylene glycol, a uniform morphology of microflowers is obtained. Owing to the multiple reaction mechanisms (insertion, conversion, and alloying) during Li insertion/extraction, the prepared electrode delivers a remarkable specific capacity of 1287 mA h g -1 at 0.2 A g -1 after 120 cycles. In addition, a high capacity of 298 mA h g -1 can be obtained at 5 A g -1 after 1400 cycles. The excellent electrochemical performance can be attributed to the high crystallinity and large specific surface area of active materials. The smaller particles after cycling could facilitate the lithium-ion transport and provide more reaction sites. The facile and scalable synthesis process and excellent electrochemical performance make this material a highly promising anode for the commercial LIBs.

  10. Molten salt synthesis of sodium lithium titanium oxide anode material for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Yin, S.Y., E-mail: yshy2004@hotmail.com [College of Environmental and Biological Engineering, Wuhan Technology and Business University, Wuhan 430065 (China); Feng, C.Q. [Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Ministry of Education Key Laboratory for Synthesis and Applications of Organic Functional Molecules, Hubei University, Wuhan 430062 (China); Wu, S.J.; Liu, H.L.; Ke, B.Q. [College of Environmental and Biological Engineering, Wuhan Technology and Business University, Wuhan 430065 (China); Zhang, K.L. [College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072 (China); Chen, D.H. [College of Environmental and Biological Engineering, Wuhan Technology and Business University, Wuhan 430065 (China); Hubei Key Laboratory for Catalysis and Material Science, College of Chemistry and Material Science, South Central University for Nationalities, Wuhan 430074, Hubei (China)

    2015-09-05

    Highlights: • Na{sub 2}Li{sub 2}Ti{sub 6}O{sub 12} has been successfully synthesized via a molten salt route. • Calcination temperature is an important effect on the component and microstructure of the product. • Pure phase Na{sub 2}Li{sub 2}Ti{sub 6}O{sub 12} could be obtained at 700 °C for 2 h. - Abstract: The sodium lithium titanium oxide with composition Na{sub 2}Li{sub 2}Ti{sub 6}O{sub 14} has been synthesized by a molten salt synthesis method using sodium chloride and potassium chloride mixture as a flux medium. Synthetic variables on the synthesis, such as sintering temperature, sintering time and the amount of lithium carbonate, were intensively investigated. Powder X-ray diffraction and scanning electron microscopy images of the reaction products indicates that pure phase sodium lithium titanium oxide has been obtained at 700 °C, and impure phase sodium hexatitanate with whiskers produced at higher temperature due to lithium evaporative losses. The results of cyclic voltammetry and discharge–charge tests demonstrate that the synthesized products prepared at various temperatures exhibited electrochemical diversities due to the difference of the components. And the sample obtained at 700 °C revealed highly reversible insertion and extraction of Li{sup +} and displayed a single potential plateau at around 1.3 V. The product obtained at 700 °C for 2 h exhibits good cycling properties and retains the specific capacity of 62 mAh g{sup −1} after 500 cycles.

  11. Characterization and electrochemical performance of lithium-active titanium dioxide inlaid LiNi0.5Co0.2Mn0.3O2 material prepared by lithium residue-assisted method

    International Nuclear Information System (INIS)

    Li, Lingjun; Chen, Zhaoyong; Song, Liubin; Xu, Ming; Zhu, Huali; Gong, Li; Zhang, Kaili

    2015-01-01

    Highlights: • LiTiO 2 -inlaid LiNi 0.5 Co 0.2 Mn 0.3 O 2 is prepared by lithium residue-assisted method. • The unique inlaid architecture inherits the advantages of coating and doping. • LiTiO 2 inlaying enhances the pristine at high cyclability and rate properties. • Excess LiTiO 2 modification results in low Li + diffusion coefficient. • The 3 mol% LiTiO 2 inlaid sample exhibits the best electrochemical performance. - Abstract: The lithium residues are consumed as raw materials to in-situ synthesize the LiTiO 2 -inlaid LiNi 0.5 Co 0.2 Mn 0.3 O 2 composites. The effects of various LiTiO 2 contents on the morphology, structure, and electrochemical properties of LiNi 0.5 Co 0.2 Mn 0.3 O 2 materials are investigated in detail. Energy dispersive spectrometer mapping, high-resolution transmission electron microscopy and fast Fourier transform analysis confirm that the spherical particles of LiNi 0.5 Co 0.2 Mn 0.3 O 2 are completely coated by crystalline LiTiO 2 phase; X-ray diffraction, cross-section SEM and corresponding EDS results indicate that Ti ions are also doped into the bulk LiNi 0.5 Co 0.2 Mn 0.3 O 2 with gradient distribution. Electrochemical tests show that the LiTiO 2 -inlaid samples exhibit excellent reversible capacity, enhanced cyclability, superior lithium diffusion coefficient and rate properties. Specially, the 3 mol% LiTiO 2 inlaid sample maintains 153.7 mA h g −1 with 94.4% capacity retention after 100 cycles between 2.7–4.4 V at 1 C, take 30% advantage than that of the pristine one (118.2 mA h g −1 ). This improvement can be attributed to the removal of lithium residues and suitable LiTiO 2 inlaying. The absence of lithium residue is helpful to retard the decomposition of LiPF 6 . While, suitable LiTiO 2 inlaying can protect the bulk from directly contacting the electrolyte, buffer the volume change of core and shell during cycles, increase the surface electronic conductivity and offer a 3D path for Li + diffusion from the bulk to

  12. Nickel/carbon core/shell nanotubes: Lanthanum nickel alloy catalyzed synthesis, characterization and studies on their ferromagnetic and lithium-ion storage properties

    International Nuclear Information System (INIS)

    Anthuvan Rajesh, John; Pandurangan, Arumugam; Senthil, Chenrayan; Sasidharan, Manickam

    2014-01-01

    Highlights: • Ni/CNTs core/shell structure was synthesized using LaNi 5 alloy catalyst by CVD. • The magnetic and lithium-ion storage properties of Ni/CNTs structure were studied. • The specific Ni/CNTs structure shows strong ferromagnetic property with large coercivity value of 446.42 Oe. • Ni/CNTs structure shows enhanced electrochemical performance in terms of stable capacity and better rate capability. - Abstract: A method was developed to synthesize ferromagnetic nickel core/carbon shell nanotubes (Ni/CNTs) by chemical vapor deposition using Pauli paramagnetic lanthanum nickel (LaNi 5 ) alloy both as a catalyst and as a source for the Ni-core. The Ni-core was obtained through oxidative dissociation followed by hydrogen reduction during the catalytic growth of the CNTs. Transmission electron microscopy (TEM), selected area electron diffraction (SAED) and X-ray diffraction (XRD) analyses reveal that the Ni-core exists as a face centered cubic single crystal. The magnetic hysteresis loop of Ni/CNTs particle shows increased coercivity (446.42 Oe) than bulk Ni at room temperature. Furthermore, the Ni/CNTs core/shell particles were investigated as anode materials in lithium-ion batteries. The Ni/CNTs electrode delivered a high discharge capacity of 309 mA h g −1 at 0.2 C, and a stable cycle-life, which is attributed to high structural stability of Ni/CNTs electrode during electrochemical lithium-ion insertion and de-insertion redox reactions

  13. Effect of Different Binders on the Electrochemical Performance of Metal Oxide Anode for Lithium-Ion Batteries

    Science.gov (United States)

    Wang, Rui; Feng, Lili; Yang, Wenrong; Zhang, Yinyin; Zhang, Yanli; Bai, Wei; Liu, Bo; Zhang, Wei; Chuan, Yongming; Zheng, Ziguang; Guan, Hongjin

    2017-10-01

    When testing the electrochemical performance of metal oxide anode for lithium-ion batteries (LIBs), binder played important role on the electrochemical performance. Which binder was more suitable for preparing transition metal oxides anodes of LIBs has not been systematically researched. Herein, five different binders such as polyvinylidene fluoride (PVDF) HSV900, PVDF 301F, PVDF Solvay5130, the mixture of styrene butadiene rubber and sodium carboxymethyl cellulose (SBR+CMC), and polyacrylonitrile (LA133) were studied to make anode electrodes (compared to the full battery). The electrochemical tests show that using SBR+CMC and LA133 binder which use water as solution were significantly better than PVDF. The SBR+CMC binder remarkably improve the bonding capacity, cycle stability, and rate performance of battery anode, and the capacity retention was about 87% after 50th cycle relative to the second cycle. SBR+CMC binder was more suitable for making transition metal oxides anodes of LIBs.

  14. Aligned TiO₂ nanotube/nanoparticle heterostructures with enhanced electrochemical performance as three-dimensional anode for lithium-ion microbatteries.

    Science.gov (United States)

    Xie, Keyu; Guo, Min; Lu, Wei; Huang, Haitao

    2014-11-14

    A novel TiO₂ three-dimensional (3D) anode with an aligned TiO₂ nanotube/nanoparticle heterostructure (TiO₂ NTs/NPs) is developed by simply immersing as-anodized TiO₂ NTs into water and further crystallizing the TiO₂ NTs by post-annealing. The heterostructure, with its core in a tubular morphology and with both the outer and inner surface consisting of nanoparticles, is confirmed by FESEM and TEM. A reversible areal capacity of 0.126 mAh · cm(-2) is retained after 50 cycles for the TiO₂ NTs/NPs heterostructure electrode, which is higher than that of the TiO₂ NTs electrode (0.102 mAh · cm(-2) after 50 cycles). At the current densities of 0.02, 0.04, 0.06, 0.08, 0.10 and 0.20 mA · cm(-2), the areal capacities are 0.142, 0.127, 0.117, 0.110, 0.104 and 0.089 mAh · cm(-2), respectively, for the TiO₂ NTs/NPs heterostructure electrode compared to the areal capacities of 0.123, 0.112, 0.105, 0.101, 0.094 and 0.083 mAh · cm(-2), respectively, for the the TiO₂ NTs electrode. The enhanced electrochemical performance is attributed to the unique microstructure of the TiO₂ NTs/NPs heterostructure electrode with the TiO₂ NT core used as a straight pathway for electronic transport and with TiO₂ NP offering enhanced surface areas for facile Li+ insertion/extraction. The results described here inspire a facile approach to fabricate a 3D anode with an enhanced electrochemical performance for lithium-ion microbattery applications.

  15. Synthesis and electrochemical properties of high performance polyhedron sphere like lithium manganese oxide for lithium ion batteries

    International Nuclear Information System (INIS)

    Guo, Donglei; Wei, Xiuge; Chang, Zhaorong; Tang, Hongwei; Li, Bao; Shangguan, Enbo; Chang, Kun; Yuan, Xiao-Zi; Wang, Haijiang

    2015-01-01

    Graphical abstract: Polyhedron structured sphere-like LiMn 2 O 4 synthesized from β-MnO 2 nanorod precursor via a solid state reaction at a temperature of 800 °C exhibits excellent rate capability and cycling performance at both 25 °C and 55 °C. - Highlights: • Polyhedron sphere-like LiMn 2 O 4 was synthesized from β-MnO 2 nanorod precursor. • The polyhedron sphere-like LiMn 2 O 4 exhibits excellent rate capability and cycling performance. • The polyhedron sphere-like structure spinel LiMn 2 O 4 suppresses the dissolution of manganese ions. • The polyhedron sphere-like LiMn 2 O 4 has high diffusion coefficient of Li + . - Abstract: Polyhedron structured sphere-like lithium manganese oxide (LiMn 2 O 4 ) is successfully synthesized from β-MnO 2 nanorod precursor via a solid state reaction at a temperature of 800 °C. For comparison, LiMn 2 O 4 materials with nanorod and octahedron structures are also obtained from β-MnO 2 nanorod precursor at temperatures of 700 °C and 900 °C, respectively. The galvanostatic charge–discharge result shows that the polyhedron sphere-like LiMn 2 O 4 sample exhibits the best electrochemical performance at high rate and high temperature. After 100 cycles at 5 C, this electrode is able to maintain 94% of its capacity at 25 °C and 81% at 55 °C. This is attributed to that the polyhedron sphere-like spinel LiMn 2 O 4 can suppress the dissolution of manganese ions. Based on Brunauer Emmett Teller (BET), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS), the polyhedron sphere-like LiMn 2 O 4 sample has the lowest BET surface area, largest diffusion coefficient of Li + and least charge transfer resistance. This study provides an insight into the capacity fading of LiMn 2 O 4 electrodes and the polyhedron structured sphere-like LiMn 2 O 4 can be a promising material for lithium ion batteries

  16. Synthesis and Electrochemical Properties of Fe-doped V6O13 as Cathode Material for Lithium-ion Battery

    Directory of Open Access Journals (Sweden)

    YUAN Qi

    2018-01-01

    Full Text Available Fe-doped V6O13 was synthesized via a facile hydrothermal method after preparing precursor in order to improve the discharge capacity and cycle performance of V6O13 cathode material at high-lithium state. XRD, SEM and XPS were employed to characterize the phase, morphology and valence of the Fe-doped V6O13. Meanwhile, the electrochemical performance was analyzed and researched. Different morphologies and electrochemical performances of Fe-doped V6O13 were obtained via doping different contents of Fe3+ ion. The sample 0.02 presented the largest thickness of nanosheets (the thickness of 600-900nm and clearance between layers. The Fe-doped V6O13 has a better electrochemical performance than that of pure V6O13. The sample 0.02 exhibits the best electrochemical performance, the initial discharge specific capacity is 433mAh·g-1 and the capacity retention is 47.1% after 100 cycles.

  17. High Rate and Stable Li-Ion Insertion in Oxygen-Deficient LiV3O8 Nanosheets as a Cathode Material for Lithium-Ion Battery.

    Science.gov (United States)

    Song, Huanqiao; Luo, Mingsheng; Wang, Aimei

    2017-01-25

    Low performance of cathode materials has become one of the major obstacles to the application of lithium-ion battery (LIB) in advanced portable electronic devices, hybrid electric vehicles, and electric vehicles. The present work reports a versatile oxygen-deficient LiV 3 O 8 (D-LVO) nanosheet that was synthesized successfully via a facile oxygen-deficient hydrothermal reaction followed by thermal annealing in Ar. When used as a cathode material for LIB, the prepared D-LVO nanosheets display remarkable capacity properties at various current densities (a capacity of 335, 317, 278, 246, 209, 167, and 133 mA h g -1 at 50, 100, 200, 500, 1000, 2000, and 4000 mA g -1 , respectively) and excellent lithium-ion storage stability, maintaining more than 88% of the initial reversible capacity after 200 cycles at 1000 mA g -1 . The outstanding electrochemical properties are believed to arise largely from the introduction of tetravalent V (∼15% V 4+ ) and the attendant oxygen vacancies into LiV 3 O 8 nanosheets, leading to intrinsic electrical conductivity more than 1 order of magnitude higher and lithium-ion diffusion coefficient nearly 2 orders of magnitude higher than those of LiV 3 O 8 without detectable V 4+ (N-LVO) and thus contributing to the easy lithium-ion diffusion, rapid phase transition, and the excellent electrochemical reversibility. Furthermore, the more uniform nanostructure, as well as the larger specific surface area of D-LVO than N-LVO nanosheets may also improve the electrolyte penetration and provide more reaction sites for fast lithium-ion diffusion during the discharge/charge processes.

  18. Equilibrium lithium-ion transport between nanocrystalline lithium-inserted anatase TiO2 and the electrolyte.

    Science.gov (United States)

    Ganapathy, Swapna; van Eck, Ernst R H; Kentgens, Arno P M; Mulder, Fokko M; Wagemaker, Marnix

    2011-12-23

    The power density of lithium-ion batteries requires the fast transfer of ions between the electrode and electrolyte. The achievable power density is directly related to the spontaneous equilibrium exchange of charged lithium ions across the electrolyte/electrode interface. Direct and unique characterization of this charge-transfer process is very difficult if not impossible, and consequently little is known about the solid/liquid ion transfer in lithium-ion-battery materials. Herein we report the direct observation by solid-state NMR spectroscopy of continuous lithium-ion exchange between the promising nanosized anatase TiO(2) electrode material and the electrolyte. Our results reveal that the energy barrier to charge transfer across the electrode/electrolyte interface is equal to or greater than the barrier to lithium-ion diffusion through the solid anatase matrix. The composition of the electrolyte and in turn the solid/electrolyte interface (SEI) has a significant effect on the electrolyte/electrode lithium-ion exchange; this suggests potential improvements in the power of batteries by optimizing the electrolyte composition. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Preparation and electrochemical properties of mesoporous NiCo2O4 double-hemisphere used as anode for lithium-ion battery.

    Science.gov (United States)

    Yang, Yue; Huang, Guo Yong; Sun, Hongyu; Ahmad, Mashkoor; Mou, Qinyao; Zhang, Hongmei

    2018-06-19

    NiCo 2 O 4 is a potential anode material for lithium ion battery due to its many advantages, such as high theoretical capacitance, low cost, and good electrochemical activity. In this study, mesoporous NiCo 2 O 4 double-hemisphere (3-5 μm) with high surface area (270.68 m 2 ·g -1 ) and excellent electrochemical performances has been synthesized through a facile precipitation method followed with thermal treatment process. The prepared NiCo 2 O 4 is pure phase and can be indexed as a face-centered-cubic with a typical spinel structure. Electrochemical tests show the prepared material has high specific capacities (910 mAh·g -1 at 100 mA·g -1 ), excellent cyclicity (908  mAh·g -1 at 100 mA·g -1 after 60 cycles) and remarkable high rate performance (after 100 cycles, 585 mAh·g -1 at 400 mAh·g -1 , 415 mAh·g -1 at 800 mAh·g -1 and 320 mAh·g -1 at 1600 mAh·g -1 with coulombic efficiencies of almost 100%). The excellent performances of prepared NiCo 2 O 4 are mainly caused by the unique double-hemisphere structure, which has large surface area, gives material more opportunity to contact with electrolyte and facilitates lithium ion spreading into the material along the radical direction, resulting in a promising application for next-generation lithium-ion batteries. Copyright © 2018 Elsevier Inc. All rights reserved.

  20. Aging Mechanisms of Electrode Materials in Lithium-Ion Batteries for Electric Vehicles

    Directory of Open Access Journals (Sweden)

    Cheng Lin

    2015-01-01

    Full Text Available Electrode material aging leads to a decrease in capacity and/or a rise in resistance of the whole cell and thus can dramatically affect the performance of lithium-ion batteries. Furthermore, the aging phenomena are extremely complicated to describe due to the coupling of various factors. In this review, we give an interpretation of capacity/power fading of electrode-oriented aging mechanisms under cycling and various storage conditions for metallic oxide-based cathodes and carbon-based anodes. For the cathode of lithium-ion batteries, the mechanical stress and strain resulting from the lithium ions insertion and extraction predominantly lead to structural disordering. Another important aging mechanism is the metal dissolution from the cathode and the subsequent deposition on the anode. For the anode, the main aging mechanisms are the loss of recyclable lithium ions caused by the formation and increasing growth of a solid electrolyte interphase (SEI and the mechanical fatigue caused by the diffusion-induced stress on the carbon anode particles. Additionally, electrode aging largely depends on the electrochemical behaviour under cycling and storage conditions and results from both structural/morphological changes and side reactions aggravated by decomposition products and protic impurities in the electrolyte.

  1. Anisotropic Lithium Insertion Behavior in Silicon Nanowires: Binding Energy, Diffusion Barrier, and Strain Effect

    KAUST Repository

    Zhang, Qianfan; Cui, Yi; Wang, Enge

    2011-01-01

    Silicon nanowires (SiNWs) have recently been shown to be promising as high capacity lithium battery anodes. SiNWs can be grown with their long axis along several different crystallographic directions. Due to distinct atomic configuration and electronic structure of SiNWs with different axial orientations, their lithium insertion behavior could be different. This paper focuses on the characteristics of single Li defects, including binding energy, diffusion barriers, and dependence on uniaxial strain in [110], [100], [111], and [112] SiNWs. Our systematic ab initio study suggests that the Si-Li interaction is weaker when the Si-Li bond direction is aligned close to the SiNW long axis. This results in the [110] and [111] SiNWs having the highest and lowest Li binding energy, respectively, and it makes the diffusion barrier along the SiNW axis lower than other pathways. Under external strain, it was found that [110] and [001] SiNWs are the most and least sensitive, respectively. For diffusion along the axial direction, the barrier increases (decreases) under tension (compression). This feature results in a considerable difference in the magnitude of the energy barrier along different diffusion pathways. © 2011 American Chemical Society.

  2. Anisotropic Lithium Insertion Behavior in Silicon Nanowires: Binding Energy, Diffusion Barrier, and Strain Effect

    KAUST Repository

    Zhang, Qianfan

    2011-05-19

    Silicon nanowires (SiNWs) have recently been shown to be promising as high capacity lithium battery anodes. SiNWs can be grown with their long axis along several different crystallographic directions. Due to distinct atomic configuration and electronic structure of SiNWs with different axial orientations, their lithium insertion behavior could be different. This paper focuses on the characteristics of single Li defects, including binding energy, diffusion barriers, and dependence on uniaxial strain in [110], [100], [111], and [112] SiNWs. Our systematic ab initio study suggests that the Si-Li interaction is weaker when the Si-Li bond direction is aligned close to the SiNW long axis. This results in the [110] and [111] SiNWs having the highest and lowest Li binding energy, respectively, and it makes the diffusion barrier along the SiNW axis lower than other pathways. Under external strain, it was found that [110] and [001] SiNWs are the most and least sensitive, respectively. For diffusion along the axial direction, the barrier increases (decreases) under tension (compression). This feature results in a considerable difference in the magnitude of the energy barrier along different diffusion pathways. © 2011 American Chemical Society.

  3. Al2O3-coated porous separator for enhanced electrochemical performance of lithium sulfur batteries

    International Nuclear Information System (INIS)

    Zhang, Zhiyong; Lai, Yanqing; Zhang, Zhian; Zhang, Kai; Li, Jie

    2014-01-01

    Graphical abstract: Al2O3-coated separator with developed porous channels is prepared by coating Al2O3 polymer solution on routine separator. The batteries with Al2O3-coated separator exhibited a reversible capacity of as high as 593 mAh g-1 at the rate of 0.2 C after 50th charge/discharge cycle. The enhancement in the electrochemical performance could be attributed to the reduced charge transfer resistance after the introduction of Al2O3 coating layer. Besides, the Al2O3 coating layer, acting as a physical barrier for polysulfides, can effectively prevent polysulfides shuttling between the cathode and the anode. We believe that the Al2O3-coated separator is promising in the lithium sulfur battery applications. - Highlights: • Al 2 O 3 -coated separator is used as the separator of lithium sulfur battery. • The cell with Al 2 O 3 -coated separator exhibits excellent cycling stability and high rate capability. • Al 2 O 3 -coated separator is promising in the lithium sulfur battery applications. - Abstract: In this paper, Al 2 O 3 -coated separator with developed porous channels is prepared to improve the electrochemical performance of lithium sulfur batteries. It is demonstrated that the Al 2 O 3 -coating layer is quite effective in reducing shuttle effect and enhancing the stability of the sulfur electrode. The initial discharge capacity of the cell with Al 2 O 3 -coated separator can reach 967 mAh g −1 at the rate of 0.2 C. After 50th charge/discharge cycle, this cell can also deliver a reversible capacity of as high as 593.4 mAh g −1 . Significantly, the charge-transfer resistance of the electrode tends to be reducing after using Al 2 O 3 -coated separator. The improved cell performance is attributed to the porous architecture of the Al 2 O 3 -coating layer, which serves as an ion-conducting skeleton for trapping and depositing dissolved sulfur-containing active materials, as confirmed by scanning electron microscopy (SEM) and energy-dispersive X

  4. Mesoporous Spinel Li4Ti5O12 Nanoparticles for High Rate Lithium-ion Battery Anodes

    International Nuclear Information System (INIS)

    Liu, Weijian; Shao, Dan; Luo, Guoen; Gao, Qiongzhi; Yan, Guangjie; He, Jiarong; Chen, Dongyang; Yu, Xiaoyuan; Fang, Yueping

    2014-01-01

    Graphical abstract: - Highlights: • Mesoporous Li 4 Ti 5 O 12 nanoparticles were prepared by a simple hydrothermal method. • The mesoporous Li 4 Ti 5 O 12 nanoparticles exhibited a diameter of 40 ± 5 nm and a pore-size distribution of 6 - 8 nm. • Cells with the mesoporous Li 4 Ti 5 O 12 anode showed excellent high rate electrochemical properties. - Abstract: Mesoporous spinel lithium titanate (Li 4 Ti 5 O 12 ) nanoparticles with the diameter of 40 ± 5 nm and the pore-size distribution of 6 - 8 nm were prepared by a simple hydrothermal method. As an anode material for lithium-ion batteries, these spinel Li 4 Ti 5 O 12 mesoporous nanoparticles exhibited desirable lithium storage properties with an initial discharge capacity of 176 mAh g −1 at 1 C rate and a capacity of approximately 145 mAh g −1 after 200 cycles at a high rate of 20 C. These excellent electrochemical properties at high charge/discharge rates are due to the mesoporous nano-scale structures with small size particles, uniform mesopores and larger electrode/electrolyte contact area, which shortens the diffusion path for both electrons and Li + ions, and offers more active sites for Li + insertion-extraction process

  5. N-doped graphene/graphite composite as a conductive agent-free anode material for lithium ion batteries with greatly enhanced electrochemical performance

    International Nuclear Information System (INIS)

    Guanghui, Wu; Ruiyi, Li; Zaijun, Li; Junkang, Liu; Zhiguo, Gu; Guangli, Wang

    2015-01-01

    Graphical abstract: The study reported a novel N-doped graphene/graphite anode material for lithium ion batteries. The composite exhibits a largely enhanced electrochemical performance. The study also provides an attractive approach for the fabrication of various graphite-based materials for high power batteries. Display Omitted -- Highlights: • The paper developed a new N-doped graphene/graphite composite for lithium ion battery • The composite contains a three-dimensional graphene framework with rich of open pores • The hybrid offers a higher electrical conductivity when compared with pristine graphite • The hybrid electrode provides a greatly enhanced electrochemical performance • The study provides a prominent approach for fabrication of graphite-based materials -- ABSTRACT: Present graphite anode cannot meet the increasing requirement of electronic devices and electric vehicles due to its low specific capacity, poor cycle stability and low rate capability. The study reported a promising N-doped graphene/graphite composite as a conductive agent-free anode material for lithium ion batteries. Herein, graphite oxide and urea were dispersed in ultrapure water and partly reduced by ascorbic acid. Followed by mixing with graphite and hydrothermal treatment to produce graphene oxide/graphite hydrogel. The hydrogel was dried and finally annealed in Ar/H 2 to obtain N-doped graphene/graphite composite. The result shows that all of graphite particles was dispersed in three-dimensional graphene framework with a rich of open pores. The open pore accelerates the electrolyte transport. The graphene framework works as a conductive agent and graphite particle connector and improves the electron transfer. Electrical conductivity of the composite reaches 5912 S m −1 , which is much better than that of the pristine graphite (4018 S m −1 ). The graphene framework also acts as an expansion absorber in the anodes of lithium ion battery to relieve the large strains

  6. Advances of aqueous rechargeable lithium-ion battery: A review

    Science.gov (United States)

    Alias, Nurhaswani; Mohamad, Ahmad Azmin

    2015-01-01

    The electrochemical characteristic of the aqueous rechargeable lithium-ion battery has been widely investigated in efforts to design a green and safe technology that can provide a highly specific capacity, high efficiency and long life for high power applications such as the smart grid and electric vehicle. It is believed that the advantages of this battery will overcome the limitations of the rechargeable lithium-ion battery with organic electrolytes that comprise safety and create high fabrication cost issues. This review focuses on the opportunities of the aqueous rechargeable lithium-ion battery compared to the conventional rechargeable lithium-ion battery with organic-based electrolytes. Previously reported studies are briefly summarised, together with the presentation of new findings based on the conductivity, morphology, electrochemical performance and cycling stability results. The factors that influence the electrochemical performance, the challenges and potential of the aqueous rechargeable lithium-ion battery are highlighted in order to understand and maintained the excellent battery performance.

  7. Boron oxide–tin oxide/graphene composite as anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Wen, Lina; Qin, Xue; Meng, Wei; Cao, Ning; Song, Zhonghai

    2016-01-01

    Highlights: • B_2O_3–SnO_2/G anode material is prepared by chemical heat solvent method for LIBs. • B_2O_3–SnO_2/G shows much improved cycling performance and rate capability. • B_2O_3 plays an important role in improving the performance. - Abstract: B_2O_3–SnO_2/graphene (B_2O_3–SnO_2/G) composite is fabricated via a chemical heat solvent method and utilized as anode material for lithium ion batteries. The added B_2O_3 dramatically improves the electrochemical performance of lithium ion batteries compared to the SnO_2/G composite. The B_2O_3–SnO_2/G composites as anode show an outstanding discharge capacity of 1404.9 mAh g"−"1 at 500 mA g"−"1 after 200 cycles and an excellent rate capacity, which apparently outperforms the previously reported SnO_2-based anode material. These improved electrochemical performance characteristics are due to the B_2O_3 played a buffering role, which are easily beneficial for accommodating the volume change during the lithium ions insertion/extraction processes. Furthermore, boron atoms can accept electrons for its electron-deficient nature and boron ions could release electrons, which lead to electrons' increased density and conductivity are increased. The results indicate that the B_2O_3–SnO_2/G composite is a promising anode material for lithium ion batteries.

  8. Synthesis and electrochemical properties of nanosized LiFeO2 particles with a layered rocksalt structure for lithium batteries

    International Nuclear Information System (INIS)

    Hirayama, Masaaki; Tomita, Hiroki; Kubota, Kei; Ido, Hidekazu; Kanno, Ryoji

    2012-01-01

    Highlights: ► 40-nm-sized O3-LiFeO 2 exhibits higher discharge capacities and rate characteristics than 400-nm-sized O3-LiFeO 2 . ► The cation disorder of Li and Fe ions might have affected the electrochemical activity of the O3-LiFeO 2 nanoparticles. ► A phase change from a layered structure to a cubic structure during electrochemical cycling. ► The new cubic phase allowed a stable electrochemical reaction between 4.5 and 1.0 V. -- Abstract: Layered rocksalt-type LiFeO 2 particles (O3-LiFeO 2 ) with average particle sizes of ca. 40 and 400 nm were synthesized by an ion exchange reaction from α-NaFeO 2 precursors. X-ray diffraction (XRD) patterns and scanning electron microscopy (SEM) images confirmed the formation of nanosized O3-LiFeO 2 . 40-nm LiFeO 2 exhibited a higher discharge capacity (115 mAh g −1 ) than 400-nm LiFeO 2 (80 mAh g −1 ), and also had better rate characteristics. The downsizing effect and cation disorder between the lithium and iron layers may have improved the electrochemical activity of the LiFeO 2 particles. Transmission electron microscopy (TEM) observation indicated a phase transition from O3-LiFeO 2 to a cubic lattice system during the electrochemical process. The cubic lithium iron oxide exhibited stable electrochemical reactions based on the Fe 2+ /Fe 3+ and Fe 2+ /Fe 0 redox couples at voltages between 4.5 and 1.0 V. The discharge capacities of 40-nm LiFeO 2 were ca. 115, 210, and 390 mAh g −1 under cutoff voltages of 4.5–2.0 V, 4.5–1.5 V, and 4.5–1.0 V, respectively.

  9. Electrochemical behavior of [(Mn(Bpy))(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 1.24} and [(Mn(Bpy){sub 0.5})(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 0.62} inorganic–organic Brannerites in lithium and sodium cells

    Energy Technology Data Exchange (ETDEWEB)

    Fernández de Luis, Roberto, E-mail: roberto.fernandez@ehu.es [Departamento de Mineralogía y Petrología, Facultad de Ciencia y Tecnología, Universidad del País Vasco, UPV/EHU, Apdo. 644, E-48080 Bilbao (Spain); Ponrouch, Alexandre, E-mail: aponrouch@icmab.es [Institut de Ciència de Materials de Barcelona (CSIC) Campus UAB, E-08193, Bellaterra, Catalonia (Spain); Rosa Palacín, M., E-mail: rosa.palacin@icmab.es [Institut de Ciència de Materials de Barcelona (CSIC) Campus UAB, E-08193, Bellaterra, Catalonia (Spain); Karmele Urtiaga, M., E-mail: karmele.urtiaga@ehu.es [Departamento de Mineralogía y Petrología, Facultad de Ciencia y Tecnología, Universidad del País Vasco, UPV/EHU, Apdo. 644, E-48080 Bilbao (Spain); Arriortua, María I., E-mail: maribel.arriortua@ehu.es [Departamento de Mineralogía y Petrología, Facultad de Ciencia y Tecnología, Universidad del País Vasco, UPV/EHU, Apdo. 644, E-48080 Bilbao (Spain)

    2014-04-01

    The performance of MnV{sub 2}O{sub 6} (MnV) and its [(Mn(Bpy))(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 1.16} (MnBpy) and [(Mn(Bpy){sub 0.5})(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 0.62}(MnBpy0.5) hybrid derivative compounds was investigated against sodium and lithium counter electrodes. For MnV{sub 2}O{sub 6} stable capacities of 850 mAh/g were achieved in lithium cells, the best value reported so far. The whole capacity is ascribed to a conversion reaction in which the amorphization of the compounds takes place. No significant differences in the capacities for the inorganic compound and the hybrid ones were observed. Interestingly, the potential hysteresis decreases in the hybrid compounds. The difference between Li and Na cell capacity most probably comes from the difference of standard potential of the two redox couples Li{sup +}/Li and Na{sup +}/Na of about ca. 0.3 V leading to an incomplete conversion reaction and thus lowers capacity in the case of Na cells. The Raman and IR ex-situ experiments after cycling indicate that the bipyridine organic ligands are completely decomposed during the electrochemical testing. The IR studies in MnV inorganic and MnBpy and MnBpy0.5 hybrid electrodes after the electrochemical cycling, suggest that the SEI formation and bipyridine degradation give rise to different aliphatic compounds. - Graphical abstract: The electrochemical performance of [(Mn(Bpy))(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 1.16} and [(Mn(Bpy){sub 0.5})(VO{sub 3}){sub 2}]≈(H{sub 2}O){sub 0.62} against sodium and lithium counter electrodes give rise to the structural collapse of the initial compounds. The IR and Raman studies show that the Bpy organic ligand is completely decomposed during the during the electrochemical testing. However, after the amorphization stable capacities as high as 850 mAh/g for lithium cells were achieved. - Highlights: • We test the lithium and sodium insertion in hybrid brannerites. • Capacities as large as 850 mAh/g were obtained

  10. Comparison of Lithium-Ion Anode Materials Using an Experimentally Verified Physics-Based Electrochemical Model

    Directory of Open Access Journals (Sweden)

    Rujian Fu

    2017-12-01

    Full Text Available Researchers are in search of parameters inside Li-ion batteries that can be utilized to control their external behavior. Physics-based electrochemical model could bridge the gap between Li+ transportation and distribution inside battery and battery performance outside. In this paper, two commercially available Li-ion anode materials: graphite and Lithium titanate (Li4Ti5O12 or LTO were selected and a physics-based electrochemical model was developed based on half-cell assembly and testing. It is found that LTO has a smaller diffusion coefficient (Ds than graphite, which causes a larger overpotential, leading to a smaller capacity utilization and, correspondingly, a shorter duration of constant current charge or discharge. However, in large current applications, LTO performs better than graphite because its effective particle radius decreases with increasing current, leading to enhanced diffusion. In addition, LTO has a higher activation overpotential in its side reactions; its degradation rate is expected to be much smaller than graphite, indicating a longer life span.

  11. Electrochemical performance of SnO{sub 2}/modified graphite composite material as anode of lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hong-Qiang [Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemical and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004 (China); Hubei Key Laboratory for Processing and Application of Catalytic Materials, Huanggang Normal University, Huanggang 438000 (China); Yang, Guan-Hua; Huang, You-Guo; Zhang, Xiao-Hui; Yan, Zhi-Xiong [Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemical and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004 (China); Li, Qing-Yu, E-mail: liqingyu62@126.com [Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemical and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004 (China)

    2015-11-01

    In this report, we synthesized SnO{sub 2}/modified graphite anode composite material by a simple reflux method using SnCl{sub 4}·5H{sub 2}O as tin source and modified graphite as carbon source. The as-obtained composite was investigated with the help of X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvanostatic cycling tests. The results show that the composite has a wave-shaped fold structure and the SnO{sub 2} nanoparticles on it have an average size of about 50 nm. Compared to pure modified graphite, the SnO{sub 2}/modified graphite exhibits a better electrochemical performance with a reversible specific capacity of 581.7 mAh g{sup −1} after 80 cycles, owing to high mechanical stress and elasticity of modified graphite could hinder the volume effect of SnO{sub 2} nanoparticles during the Li{sup +} insertion/extraction process. All these favourable characters reveal that the composite is a great potential anode material in high-performance lithium ion batteries. - Highlights: • A simple synthetic method of SnO{sub 2}/modified graphite composite as anode. • The as-prepared composite with layered structure alleviates the huge reunion of SnO{sub 2}. • The composite exhibits a good capacity retention rate of 85.8% after 25 cycles.

  12. Parallelized Genetic Identification of the Thermal-Electrochemical Model for Lithium-Ion Battery

    Directory of Open Access Journals (Sweden)

    Liqiang Zhang

    2013-01-01

    Full Text Available The parameters of a well predicted model can be used as health characteristics for Lithium-ion battery. This article reports a parallelized parameter identification of the thermal-electrochemical model, which significantly reduces the time consumption of parameter identification. Since the P2D model has the most predictability, it is chosen for further research and expanded to the thermal-electrochemical model by coupling thermal effect and temperature-dependent parameters. Then Genetic Algorithm is used for parameter identification, but it takes too much time because of the long time simulation of model. For this reason, a computer cluster is built by surplus computing resource in our laboratory based on Parallel Computing Toolbox and Distributed Computing Server in MATLAB. The performance of two parallelized methods, namely Single Program Multiple Data (SPMD and parallel FOR loop (PARFOR, is investigated and then the parallelized GA identification is proposed. With this method, model simulations running parallelly and the parameter identification could be speeded up more than a dozen times, and the identification result is batter than that from serial GA. This conclusion is validated by model parameter identification of a real LiFePO4 battery.

  13. Allylic ionic liquid electrolyte-assisted electrochemical surface passivation of LiCoO2 for advanced, safe lithium-ion batteries

    Science.gov (United States)

    Mun, Junyoung; Yim, Taeeun; Park, Jang Hoon; Ryu, Ji Heon; Lee, Sang Young; Kim, Young Gyu; Oh, Seung M.

    2014-01-01

    Room-temperature ionic liquid (RTIL) electrolytes have attracted much attention for use in advanced, safe lithium-ion batteries (LIB) owing to their nonvolatility, high conductivity, and great thermal stability. However, LIBs containing RTIL-electrolytes exhibit poor cyclability because electrochemical side reactions cause problematic surface failures of the cathode. Here, we demonstrate that a thin, homogeneous surface film, which is electrochemically generated on LiCoO2 from an RTIL-electrolyte containing an unsaturated substituent on the cation (1-allyl-1-methylpiperidinium bis(trifluoromethanesulfonyl)imide, AMPip-TFSI), can avert undesired side reactions. The derived surface film comprised of a high amount of organic species from the RTIL cations homogenously covered LiCoO2 with a <25 nm layer and helped suppress unfavorable thermal reactions as well as electrochemical side reactions. The superior performance of the cell containing the AMPip-TFSI electrolyte was further elucidated by surface, electrochemical, and thermal analyses. PMID:25168309

  14. Co-estimation of state-of-charge, capacity and resistance for lithium-ion batteries based on a high-fidelity electrochemical model

    International Nuclear Information System (INIS)

    Zheng, Linfeng; Zhang, Lei; Zhu, Jianguo; Wang, Guoxiu; Jiang, Jiuchun

    2016-01-01

    Highlights: • The numerical solution for an electrochemical model is presented. • Trinal PI observers are used to concurrently estimate SOC, capacity and resistance. • An iteration-approaching method is incorporated to enhance estimation performance. • The robustness against aging and temperature variations is experimentally verified. - Abstract: Lithium-ion batteries have been widely used as enabling energy storage in many industrial fields. Accurate modeling and state estimation play fundamental roles in ensuring safe, reliable and efficient operation of lithium-ion battery systems. A physics-based electrochemical model (EM) is highly desirable for its inherent ability to push batteries to operate at their physical limits. For state-of-charge (SOC) estimation, the continuous capacity fade and resistance deterioration are more prone to erroneous estimation results. In this paper, trinal proportional-integral (PI) observers with a reduced physics-based EM are proposed to simultaneously estimate SOC, capacity and resistance for lithium-ion batteries. Firstly, a numerical solution for the employed model is derived. PI observers are then developed to realize the co-estimation of battery SOC, capacity and resistance. The moving-window ampere-hour counting technique and the iteration-approaching method are also incorporated for the estimation accuracy improvement. The robustness of the proposed approach against erroneous initial values, different battery cell aging levels and ambient temperatures is systematically evaluated, and the experimental results verify the effectiveness of the proposed method.

  15. A New All-Solid-State Hyperbranched Star Polymer Electrolyte for Lithium Ion Batteries: Synthesis and Electrochemical Properties

    International Nuclear Information System (INIS)

    Wang, Ailian; Xu, Hao; Zhou, Qian; Liu, Xu; Li, Zhengyao; Gao, Rui; Wu, Na; Guo, Yuguo; Li, Huayi; Zhang, Liaoyun

    2016-01-01

    Highlights: • A new hyperbranched multi-arm star polymer was successfully synthesized. • The star polymer electrolyte has good thermal stability and forming-film property. • The ion conductivity electrolyte can reach 8.3 × 10"−"5 S cm"−"1 at room temperature. • The star polymer electrolyte has wide electrochemical windows of 4.7 V. - Abstract: A new hyperbranched multi-arm star polymer with hyperbranched polystyrene (HBPS) as core and polymethyl methacrylate-block-poly(ethylene glycol) methyl ether methacrylate(PMMA-b-PPEGMA) as arms was firstly synthesized by atom transfer radical polymerization. The obtained hyperbranched multi-arm star polymer (HBPS-(PMMA-b-PPEGMA)_x) exhibited good thermal stability with a thermal decomposition temperature of 372 °C. The transparent, free-standing, flexible polymer electrolyte film of the blending of HBPS-(PMMA-b-PPEGMA)_x and lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) was successfully fabricated by a solution casting method. The ionic conductivity of the hyperbranched star polymer electrolyte with a molar ratio of [EO]/[Li] of 30 could reach 8.3 × 10"−"5 S cm"−"1 at 30 °C (with the content of PPEGMA of 83.7%), and 2.0 × 10"−"4 S cm"−"1 at 80 °C (with the content of PPEGMA of 51.6%). The effect of the concentration of lithium salts on ionic conductivity was also investigated. The obtained all-solid-state polymer electrolyte possessed a wide electrochemical stability window of 4.7 V (vs. Li"+/Li), and a lithium-ion transference number (t_L_i"+) up to 0.31. The interfacial impedance of the fabricated LiÔöépolymer electrolyteÔöéLi symmetric cell based on hyperbranched star multi-arm polymer electrolyte exhibited good interfacial compatibility between all-solid-state polymer electrolyte and electrodes. The excellent properties of the hyperbranched star polymer electrolyte made it attractive as solid-state polymer electrolyte for lithium-ion batteries.

  16. Temperature-dependent electrochemical heat generation in a commercial lithium-ion battery

    Science.gov (United States)

    Bandhauer, Todd M.; Garimella, Srinivas; Fuller, Thomas F.

    2014-02-01

    Lithium-ion batteries suffer from inherent thermal limitations (i.e., capacity fade and thermal runaway); thus, it is critical to understand heat generation experienced in the batteries under normal operation. In the current study, reversible and irreversible electrochemical heat generation rates were measured experimentally on a small commercially available C/LiFePO4 lithium-ion battery designed for high-rate applications. The battery was tested over a wide range of temperatures (10-60 °C) and discharge and charge rates (∼C/4-5C) to elucidate their effects. Two samples were tested in a specially designed wind tunnel to maintain constant battery surface temperature within a maximum variation of ±0.88 °C. A data normalization technique was employed to account for the observed capacity fade, which was largest at the highest rates. The heat rate was shown to increase with both increasing rate and decreasing temperature, and the reversible heat rate was shown to be significant even at the highest rate and temperature (7.4% at 5C and 55 °C). Results from cycling the battery using a dynamic power profile also showed that constant-current data predict the dynamic performance data well. In addition, the reversible heat rate in the dynamic simulation was shown to be significant, especially for charge-depleting HEV applications.

  17. Hierarchical structured graphene/metal oxide/porous carbon composites as anode materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Rong [Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing 100875 (China); Yue, Wenbo, E-mail: wbyue@bnu.edu.cn [Beijing Key Laboratory of Energy Conversion and Storage Materials, College of Chemistry, Beijing Normal University, Beijing 100875 (China); Ren, Yu [National Institute of Clean-and-Low-Carbon Energy, Beijing 102209 (China); Zhou, Wuzong [School of Chemistry, University of St. Andrews, St. Andrews, Fite KY16 9ST (United Kingdom)

    2016-01-15

    Highlights: • CeO{sub 2} and Co{sub 3}O{sub 4} nanoparticles display different behavior within CMK-3. • CMK-3-CeO{sub 2} and Co{sub 3}O{sub 4} show various electrochemical properties • CMK-3-CeO{sub 2} and Co{sub 3}O{sub 4} are further wrapped by graphene nanosheets. • Graphene-encapsulated composites show better electrochemical performances. - Abstract: As a novel anode material for lithium-ion batteries, CeO{sub 2} displays imperceptible volumetric and morphological changes during the lithium insertion and extraction processes, and thereby exhibits good cycling stability. However, the low theoretical capacity and poor electronic conductivity of CeO{sub 2} hinder its practical application. In contrast, Co{sub 3}O{sub 4} possesses high theoretical capacity, but undergoes huge volume change during cycling. To overcome these issues, CeO{sub 2} and Co{sub 3}O{sub 4} nanoparticles are formed inside the pores of CMK-3 and display various electrochemical behaviors due to the different morphological structures of CeO{sub 2} and Co{sub 3}O{sub 4} within CMK-3. Moreover, the graphene/metal oxide/CMK-3 composites with a hierarchical structure are then prepared and exhibit better electrochemical performances than metal oxides with or without CMK-3. This novel synthesis strategy is hopefully employed in the electrode materials design for Li-ion batteries or other energy conversion and storage devices.

  18. Facile synthesis of Fe-incorporated CuO nanoarrays with enhanced electrochemical performance for lithium ion full batteries

    Energy Technology Data Exchange (ETDEWEB)

    Heng, Bojun [Institute of Nano-science and Technology, Central-China Normal University, Wuhan, 430079 (China); Department of Applied Physics, Wuhan University of Science and Technology, Wuhan, 430065 (China); Qing, Chen; Wang, Hai; Sun, Daming; Wang, Bixiao [Institute of Nano-science and Technology, Central-China Normal University, Wuhan, 430079 (China); Tang, Yiwen, E-mail: ywtang@phy.ccnu.edu.cn [Institute of Nano-science and Technology, Central-China Normal University, Wuhan, 430079 (China)

    2015-11-15

    CuO nanoarrays (CNAs) and Fe-incorporated CuO nanoarrays (FCNAs) were fabricated by hydrothermal method. Addition of Fe salt to the reaction mixture allowed the introduction of iron oxide onto the CNAs surface, which was characterized by XPS and HRTEM. Introducing Fe ion into reaction precursor significantly affected not only the morphologies of as-prepared products but also their electrochemical performance as anode for lithium ion full battery. The FCNAs electrodes showed higher specific capacity and better capacity retention at different current densities than that of CNAs. - Highlights: • Fe-incorporated CuO nanoarrays were fabricated by hydrothermal method. • Fe salt in reaction mixture leads to iron oxides forming on the surface of CuO. • Fe-incorporating improves the lithium ion battery performance of CuO anodes.

  19. Electrochemical synthesis of 1D core-shell Si/TiO2 nanotubes for lithium ion batteries

    Science.gov (United States)

    Kowalski, Damian; Mallet, Jeremy; Thomas, Shibin; Nemaga, Abirdu Woreka; Michel, Jean; Guery, Claude; Molinari, Michael; Morcrette, Mathieu

    2017-09-01

    Silicon negative electrode for lithium ion battery was designed in the form of self-organized 1D core-shell nanotubes to overcome shortcomings linked to silicon volume expansion upon lithiation/delithiation typically occurring with Si nanoparticles. The negative electrode was formed on TiO2 nanotubes in two step electrochemical synthesis by means of anodizing of titanium and electrodeposition of silicon using ionic liquid electrolytes. Remarkably, it was found that the silicon grows perpendicularly to the z-axis of nanotube and therefore its thickness can be precisely controlled by the charge passed in the electrochemical protocol. Deposited silicon creates a continuous Si network on TiO2 nanotubes without grain boundaries and particle-particle interfaces, defining its electrochemical characteristics under battery testing. In the core-shell system the titania nanotube play a role of volume expansion stabilizer framework holding the nanostructured silicon upon lithiation/delithiation. The nature of Si shell and presence of titania core determine stable performance as negative electrode tested in half cell of CR2032 coin cell battery.

  20. Improved electrochemical performance of natural honeycomb templated LiSbO3 as an anode in lithium-ion battery

    International Nuclear Information System (INIS)

    Kundu, M.; Mahanty, S.; Basu, R.N.

    2011-01-01

    Highlights: → LiSbO 3 powders are synthesized by using honeycomb from natural beehive as template. → Agglomeration-free morphology with discrete cubic shaped 40-80 nm particles. → Electrochemically active anode in lithium-ion coin cells. → Improved capacity retention and rate performance in templated LiSbO 3 . - Abstract: LiSbO 3 has been synthesized by wet-chemical route using natural honeycomb as template, followed by thermal treatment at 850 deg. C. X-ray powder diffraction (XRD) confirms a single phase material having an orthorhombic crystal structure with lattice parameters of a = 4.912 A, b = 8.679 A and c = 5.089 A. Field emission scanning electron microscopy (FESEM) revealed that while conventional LiSbO 3 synthesized without using any template (C-LiSbO 3 ) consists of softly agglomerated clusters of bar-shaped multifaceted micrometer-sized grains (0.5-4.0 μm long and 0.5-1.0 μm wide), templated LiSbO 3 (T-LiSbO 3 ) consists of an agglomeration-free morphology with discrete cubic shaped particles of sizes 40-80 nm. Electrochemical investigation in 2032 type coin cells vs Li/Li + shows that Li insertion in LiSbO 3 takes place at 0.78 V while Li extraction occurs in two stages at 1.1 and 1.4 V with initial capacities of 178 and 196 mAh g -1 for C-LiSbO 3 and T-LiSbO 3 respectively. While C-LiSbO 3 shows a drastic capacity fading retaining only 28% of initial capacity after 100 cycles, T-LiSbO 3 retains ∼48% of the initial capacity due to the faceted morphology of the nanoparticles.

  1. Electrochemical-thermal Modeling to Evaluate Active Thermal Management of a Lithium-ion Battery Module

    International Nuclear Information System (INIS)

    Bahiraei, Farid; Fartaj, Amir; Nazri, Gholam-Abbas

    2017-01-01

    Lithium-ion batteries are commonly used in hybrid electric and full electric vehicles (HEV and EV). In HEV, thermal management is a strict requirement to control the batteries temperature within an optimal range in order to enhance performance, safety, reduce cost, and prolong the batteries lifetime. The optimum design of a thermal management system depends on the thermo-electrochemical behavior of the batteries, operating conditions, and weight and volume constraints. The aim of this study is to investigate the effects of various operating and design parameters on the thermal performance of a battery module consisted of six building block cells. An electrochemical-thermal model coupled to conjugate heat transfer and fluid dynamics simulations is used to assess the effectiveness of two indirect liquid thermal management approaches under the FUDC driving cycle. In this study, a novel pseudo 3D electrochemical-thermal model of the battery is used. It is found that the cooling plate thickness has a significant effect on the maximum and gradient of temperature in the module. Increasing the Reynolds number decreases the average temperature but at the expense of temperature uniformity. The results show that double channel cooling system has a lower maximum temperature and more uniform temperature distribution compared to a single channel cooling system.

  2. Exploration of artificial neural network [ANN] to predict the electrochemical characteristics of lithium-ion cells

    Energy Technology Data Exchange (ETDEWEB)

    Parthiban, Thirumalai; Ravi, R.; Kalaiselvi, N. [Central Electrochemical Research Institute (CECRI), Karaikudi 630006 (India)

    2007-12-31

    CoO anode, as an alternate to the carbonaceous anodes of lithium-ion cells has been prepared and investigated for electrochemical charge-discharge characteristics for about 50 cycles. Artificial neural networks (ANNs), which are useful in estimating battery performance, has been deployed for the first time to forecast and to verify the charge-discharge behavior of lithium-ion cells containing CoO anode for a total of 50 cycles. In this novel approach, ANN that has one input layer with one neuron corresponding to one input variable, viz., cycles [charge-discharge cycles] and a hidden layer consisting of three neurons to produce their outputs to the output layer through a sigmoid function has been selected for the present investigation. The output layer consists of two neurons, representing the charge and discharge capacity, whose activation function is also the sigmoid transfer function. In this ever first attempt to exploit ANN as an effective theoretical tool to understand the charge-discharge characteristics of lithium-ion cells, an excellent agreement between the calculated and observed capacity values was found with CoO anodes with the best fit values corresponding to an error factor of <1%, which is the highlight of the present study. (author)

  3. Freeze-drying synthesis of three-dimensional porous LiFePO{sub 4} modified with well-dispersed nitrogen-doped carbon nanotubes for high-performance lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Tu, Xiaofeng; Zhou, Yingke, E-mail: zhouyk888@hotmail.com; Song, Yijie

    2017-04-01

    Highlights: • Three-dimensional porous LiFePO{sub 4}/N-CNTs is synthesized by a freeze-drying method. • The N-CNTs conductive network enhances the electron transport within the LiFePO{sub 4} electrode. • The continuous pores accelerate the diffusion of lithium ions. • LiFePO{sub 4}/N-CNTs demonstrates an excellent electrochemical Li-insertion performance. - Abstract: The three-dimensional porous LiFePO{sub 4} modified with uniformly dispersed nitrogen-doped carbon nanotubes has been successfully prepared by a freeze-drying method. The morphology and structure of the porous composites are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), and the electrochemical performances are evaluated using the constant current charge/discharge tests, cyclic voltammetry and electrochemical impedance spectroscopy. The nitrogen-doped carbon nanotubes are uniformly dispersed inside the porous LiFePO{sub 4} to construct a superior three-dimensional conductive network, which remarkably increases the electronic conductivity and accelerates the diffusion of lithium ion. The porous composite displays high specific capacity, good rate capability and excellent cycling stability, rendering it a promising positive electrode material for high-performance lithium-ion batteries.

  4. Physico-Chemical and Electrochemical Properties of Nanoparticulate NiO/C Composites for High Performance Lithium and Sodium Ion Battery Anodes

    Directory of Open Access Journals (Sweden)

    Amaia Iturrondobeitia

    2017-12-01

    Full Text Available Nanoparticulate NiO and NiO/C composites with different carbon proportions have been prepared for anode application in lithium and sodium ion batteries. Structural characterization demonstrated the presence of metallic Ni in the composites. Morphological study revealed that the NiO and Ni nanoparticles were well dispersed in the matrix of amorphous carbon. The electrochemical study showed that the lithium ion batteries (LIBs, containing composites with carbon, have promising electrochemical performances, delivering specific discharge capacities of 550 mAh/g after operating for 100 cycles at 1C. These excellent results could be explained by the homogeneity of particle size and structure, as well as the uniform distribution of NiO/Ni nanoparticles in the in situ generated amorphous carbon matrix. On the other hand, the sodium ion battery (NIB with the NiO/C composite revealed a poor cycling stability. Post-mortem analyses revealed that this fact could be ascribed to the absence of a stable Solid Electrolyte Interface (SEI or passivation layer upon cycling.

  5. Coupling of Mechanical Behavior of Lithium Ion Cells to Electrochemical-Thermal Models for Battery Crush; NREL (National Renewable Energy Laboratory)

    Energy Technology Data Exchange (ETDEWEB)

    Pesaran, Ahmad; Zhang, Chao; Santhanagopalan, Shriram; Sahraei, Elham; Wierzbiki, Tom

    2015-06-15

    Propagation of failure in lithium-ion batteries during field events or under abuse is a strong function of the mechanical response of the different components in the battery. Whereas thermal and electrochemical models that capture the abuse response of batteries have been developed and matured over the years, the interaction between the mechanical behavior and the thermal response of these batteries is not very well understood. With support from the Department of Energy, NREL has made progress in coupling mechanical, thermal, and electrochemical lithium-ion models to predict the initiation and propagation of short circuits under external crush in a cell. The challenge with a cell crush simulation is to estimate the magnitude and location of the short. To address this, the model includes an explicit representation of each individual component such as the active material, current collector, separator, etc., and predicts their mechanical deformation under different crush scenarios. Initial results show reasonable agreement with experiments. In this presentation, the versatility of the approach for use with different design factors, cell formats and chemistries is explored using examples.

  6. Electrochemical zinc insertion into W18O49: Synthesis and characterization of new bronzes

    International Nuclear Information System (INIS)

    Martinez-de la Cruz, A.; Amador, U.; Rodriguez-Carvajal, J.; Garcia-Alvarado, F.

    2005-01-01

    Divalent zinc ions have been electrochemically inserted into W 18 O 49 , producing zinc bronzes. Under our experimental conditions, W 18 O 49 accepts zinc reversibly as a guest up to 0.9 ions per formula. The reaction seems to proceed through the formation of a solid solution in which the W-O framework of the parent oxide is maintained. The location of the Zn 2+ ions in the framework of W 18 O 49 has been determined by neutron diffraction on a chemically prepared sample having the composition Zn 0.34 W 18 O 49 . As a main result, we found that Zn prefers to insert in one of the four types of quadrangular tunnels. More precisely, it is displaced from the center to occupy a low coordination site. This result indicates that a significant covalent character exists in the Zn-O bond. - Graphical Abstract: The structure of Zn 0.36 W 18 O 49 projected along the b-axis

  7. Empirical Modeling of Lithium-ion Batteries Based on Electrochemical Impedance Spectroscopy Tests

    International Nuclear Information System (INIS)

    Samadani, Ehsan; Farhad, Siamak; Scott, William; Mastali, Mehrdad; Gimenez, Leonardo E.; Fowler, Michael; Fraser, Roydon A.

    2015-01-01

    Highlights: • Two commercial Lithium-ion batteries are studied through HPPC and EIS tests. • An equivalent circuit model is developed for a range of operating conditions. • This model improves the current battery empirical models for vehicle applications • This model is proved to be efficient in terms of predicting HPPC test resistances. - ABSTRACT: An empirical model for commercial lithium-ion batteries is developed based on electrochemical impedance spectroscopy (EIS) tests. An equivalent circuit is established according to EIS test observations at various battery states of charge and temperatures. A Laplace transfer time based model is developed based on the circuit which can predict the battery operating output potential difference in battery electric and plug-in hybrid vehicles at various operating conditions. This model demonstrates up to 6% improvement compared to simple resistance and Thevenin models and is suitable for modeling and on-board controller purposes. Results also show that this model can be used to predict the battery internal resistance obtained from hybrid pulse power characterization (HPPC) tests to within 20 percent, making it suitable for low to medium fidelity powertrain design purposes. In total, this simple battery model can be employed as a real-time model in electrified vehicle battery management systems

  8. A Novel synthesis of MgS and its application as electrode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Wang, Minjuan; Li, Xiang; Gao, Mingxia; Pan, Hongge; Liu, Yongfeng

    2014-01-01

    Highlights: • Nanocrystallite MgS was synthesized by means of a reaction of MgH 2 of S via ball milling. • MgS was firstly investigated as anode material for lithium-ion batteries (LIBs). • MgS with acetylene black introduced by ball milling shows superior electrochemical property. • The mechanisms of the lithium insertion and extraction processes of MgS are discussed. • The work is considered helpful in developing new electrode material for LIBs. - Abstract: MgS was firstly investigated as an anode material for lithium-ion batteries (LIBs). A novel method for the synthesis of nano-sized MgS was conducted, i.e., by means of a reaction of MgH 2 of S via ball milling. Acetylene black (AB) was used as electron conductive agent and introduced by two approaches to the MgS anode material: the one is ball milling AB with the as-prepared MgS derived from MgH 2 and S; the other is pre-milling AB with S and then further milling the mixture with MgH 2 . X-ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM) and high resolution TEM analyses show that MgS/AB composites with MgS nanocrystallites embedded in the AB matrix are formed via either of the approaches. The MgS anode derived from MgH 2 and the pre-milled S/AB mixture shows high capacity. Capacity fading occurs mainly in the initial several cycles. A capacity of 630 mA h/g is retained after 80 cycles. The electrochemical property is much better than that of the MgS/AB derived from MgS and AB, due to the much homogenous microstructure of the former. The mechanism of the lithium insertion and extraction process of MgS is primarily discussed. The work is considered helpful in developing new synthesis method for MgS and new electrode material for LIBs

  9. Characterization of LT-LiXO1-YNIYO2 electrodes for rechargeable lithium cells

    CSIR Research Space (South Africa)

    Gummow, RJ

    1993-12-01

    Full Text Available -spinel in character and that LT- Li0.4Co0.sNi0.102 is a defect spinel with spinel notation {Li0.s\\[:\\]0.2}sa \\[Co, 6Nio.2D0.2104. Electrochemical data.--The charge and discharge pro- files for the first four cycles of Li/LT-LiCoO2, Li... on the B sites of an A\\[B2104 spinel structure. The spinel phase is significantly more stable to lithium insertion/extraction reactions than the quasi-spinel phase. It is believed that by optimizing the processing conditions...

  10. Electrochemical impedance characterization of FeSn2 electrodes for Li-ion batteries

    International Nuclear Information System (INIS)

    Chamas, M.; Lippens, P-E.; Jumas, J-C.; Hassoun, J.; Panero, S.; Scrosati, B.

    2011-01-01

    Highlights: → In this paper we study a tin based, FeSn 2 , high capacity lithium-alloying electrode. → The electrochemical performance of this electrode in lithium batteries is remarkably influenced by the current rate. → This aspect is investigated by electrochemical techniques such as galvanostatic cycling and impedance spectroscopy. → The results demonstrated that the good electrochemical behavior of the electrode at the higher currents is due to the formation of a stable solid electrolyte interphase (SEI) film. - Abstract: This work reports the electrochemical characterization of a micro-scale FeSn 2 electrode in a lithium battery. The electrode is proposed as anode material for advanced lithium ion batteries due to its characteristics of high capacity (500 mAh g -1 ) and low working voltage (0.6 V vs. Li). The electrochemical alloying process is studied by cyclic voltammetry and galvanostatic cycling while the interfacial properties are investigated by electrochemical impedance spectroscopy. The impedance measurements in combination with the galvanostatic cycling tests reveal relatively low overall impedance values and good electrochemical performance for the electrode, both in terms of delivered capacity and cycling stability, even at the higher C-rate regimes.

  11. Effects of low-pressure nitrogen plasma treatment on the surface properties and electrochemical performance of the polyethylene separator used lithium-ion batteries

    Science.gov (United States)

    Li, Chun; Li, Hsiao-Ling; Li, Chi-Heng; Liu, Yu-Shuan; Sung, Yu-Ching; Huang, Chun

    2018-01-01

    In this paper, we describe the surface transition of the polyethylene (PE) separator used in lithium-ion batteries treated by low-pressure nitrogen plasma discharge. The nitrogen-plasma-treated PE separator was characterized by contact angle measurement, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. The electrochemical performance of the lithium ion batteries fabricated with the nitrogen-plasma-treated separator was also evaluated. Results showed that polar functionalization groups were induced on the PE surface by the nitrogen plasma discharge, causing the surface to become hydrophilic. The increases in surface wettability and surface free energy result in electrolyte retention improvement. Moreover, the nitrogen plasma-treated PE separator leads to superior performance in lithium-ion battery assembly.

  12. Copper-substituted, lithium rich iron phosphate as cathode material for lithium secondary batteries

    International Nuclear Information System (INIS)

    Lee, S.B.; Cho, S.H.; Heo, J.B.; Aravindan, V.; Kim, H.S.; Lee, Y.S.

    2009-01-01

    Carbon-free, copper-doped, lithium rich iron phosphates, Li 1+x Fe 1-y Cu y PO 4 (0 ≤ x ≤ 0.15, 0 ≤ y ≤ 0.005), have been synthesized by a solid-state reaction method. From the optimization, the Li 1.05 Fe 0.997 Cu 0.003 PO 4 phase showed superior performances in terms of phase purity and high discharge capacity. The structural, morphological, and electrochemical properties were studied and compared to LiFePO 4 , Li 1.05 FePO 4 , LiFe 0.997 Cu 0.003 PO 4 , and materials. X-ray photoelectron spectroscopy (XPS) was conducted to ensure copper doping. Only smooth surface morphologies were observed for lithium rich iron phosphates, namely Li 1.05 FePO 4 and Li 1.05 Fe 0.997 Cu 0.003 PO 4 . The Li/Li 1.05 Fe 0.997 Cu 0.003 PO 4 cell delivered an initial discharge capacity of 145 mAh/g and was 18 mAh/g higher than the Li/LiFePO 4 cell without any carbon coating effect. Cyclic voltammetry revealed excellent reversibility of the Li 1.05 Fe 0.997 Cu 0.003 PO 4 material. High rate capability studies were also performed and showed a capacity retention over 95% during the cycling. We concluded that substituted Li and Cu ions play an important role in enhancing battery performance of the LiFePO 4 material through improving the kinetics of the lithium insertion/extraction reaction on the electrode.

  13. Effect of covalently bonded polysiloxane multilayers on the electrochemical behavior of graphite electrode in lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Qinmin; Jiang, Yinghua [Department of Applied Chemistry, Harbin Institute of Technology, Harbin 150001 (China)

    2008-03-15

    Polysiloxane multilayers were covalently bonded to the surface of natural graphite particles via diazonium chemistry and silylation reaction. The as-prepared graphite exhibited excellent discharge-charge behavior as negative electrode materials in lithium ion batteries. The improvement in the electrochemical performance of the graphite electrodes was attributed to the formation of a stable and flexible passive film on their surfaces. It was also revealed that the chemical compositions of the multilayers exerted influence on the electrochemical behavior of the graphite electrodes. The result of this study presents a new strategy to the formation of elastic and strong passive film on the graphite electrode via molecular design. Owing to the diversity of polysilxoane multilayers, this method also enables researchers to control the surface chemistries of carbonaceous materials with flexibility. (author)

  14. Boron oxide–tin oxide/graphene composite as anode materials for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wen, Lina [Department of chemistry, School of Science, Tianjin University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072 (China); Qin, Xue, E-mail: qinxue@tju.edu.cn [Department of chemistry, School of Science, Tianjin University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072 (China); Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), College of Chemistry, Nankai University, Tianjin 300071 (China); Meng, Wei; Cao, Ning; Song, Zhonghai [Department of chemistry, School of Science, Tianjin University, and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin 300072 (China)

    2016-11-15

    Highlights: • B{sub 2}O{sub 3}–SnO{sub 2}/G anode material is prepared by chemical heat solvent method for LIBs. • B{sub 2}O{sub 3}–SnO{sub 2}/G shows much improved cycling performance and rate capability. • B{sub 2}O{sub 3} plays an important role in improving the performance. - Abstract: B{sub 2}O{sub 3}–SnO{sub 2}/graphene (B{sub 2}O{sub 3}–SnO{sub 2}/G) composite is fabricated via a chemical heat solvent method and utilized as anode material for lithium ion batteries. The added B{sub 2}O{sub 3} dramatically improves the electrochemical performance of lithium ion batteries compared to the SnO{sub 2}/G composite. The B{sub 2}O{sub 3}–SnO{sub 2}/G composites as anode show an outstanding discharge capacity of 1404.9 mAh g{sup −1} at 500 mA g{sup −1} after 200 cycles and an excellent rate capacity, which apparently outperforms the previously reported SnO{sub 2}-based anode material. These improved electrochemical performance characteristics are due to the B{sub 2}O{sub 3} played a buffering role, which are easily beneficial for accommodating the volume change during the lithium ions insertion/extraction processes. Furthermore, boron atoms can accept electrons for its electron-deficient nature and boron ions could release electrons, which lead to electrons' increased density and conductivity are increased. The results indicate that the B{sub 2}O{sub 3}–SnO{sub 2}/G composite is a promising anode material for lithium ion batteries.

  15. Quantifying microstructural dynamics and electrochemical activity of graphite and silicon-graphite lithium ion battery anodes

    Science.gov (United States)

    Pietsch, Patrick; Westhoff, Daniel; Feinauer, Julian; Eller, Jens; Marone, Federica; Stampanoni, Marco; Schmidt, Volker; Wood, Vanessa

    2016-09-01

    Despite numerous studies presenting advances in tomographic imaging and analysis of lithium ion batteries, graphite-based anodes have received little attention. Weak X-ray attenuation of graphite and, as a result, poor contrast between graphite and the other carbon-based components in an electrode pore space renders data analysis challenging. Here we demonstrate operando tomography of weakly attenuating electrodes during electrochemical (de)lithiation. We use propagation-based phase contrast tomography to facilitate the differentiation between weakly attenuating materials and apply digital volume correlation to capture the dynamics of the electrodes during operation. After validating that we can quantify the local electrochemical activity and microstructural changes throughout graphite electrodes, we apply our technique to graphite-silicon composite electrodes. We show that microstructural changes that occur during (de)lithiation of a pure graphite electrode are of the same order of magnitude as spatial inhomogeneities within it, while strain in composite electrodes is locally pronounced and introduces significant microstructural changes.

  16. A comparative study of electrochemical performance of graphene sheets, expanded graphite and natural graphite as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Bai, Li-Zhong; Zhao, Dong-Lin; Zhang, Tai-Ming; Xie, Wei-Gang; Zhang, Ji-Ming; Shen, Zeng-Min

    2013-01-01

    Highlights: • Graphene sheets (GSs), expanded graphite (EG) and natural graphite (NG) were comparatively investigated as anode materials for lithium-ion batteries. • The reversible capacity of GS electrode was almost twice that of EG electrode and three times that of NG electrode. • The first-cycle coulombic efficiency and capacity retention of NG were much bigger than those of GSs and EG. • GS and EG electrodes exhibited higher electrochemical activity and more favorable kinetic properties. -- Abstract: Three kinds of carbon materials, i.e., graphene sheets (GSs), expanded graphite (EG) and natural graphite (NG) were comparatively investigated as anode materials for lithium-ion batteries via scanning electron microscope, high-resolution transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy and a variety of electrochemical testing techniques. The test results showed that the reversible capacities of GS electrode were 1130 and 636 mA h g −1 at the current densities of 0.2 and 1 mA cm −2 , respectively, which were almost twice those of EG electrode and three times those of NG electrode. The first-cycle coulombic efficiency and capacity retention of NG were much bigger than those of GSs and EG. The notable capacity fading observed in GSs and EG may be ascribed to the disorder-induced structure instability. The larger voltage hysteresis in GS and EG electrodes was not only related to the surface functional groups, but also to the active defects in GSs and EG, which results in greater hindrance and higher overvoltage during lithium extraction from electrode. The kinetics properties of GSs, EG and NG electrodes were compared by AC impedance measurements. GS and EG electrodes exhibited higher electrochemical activity and more favorable kinetic properties during charge and discharge process

  17. Development of reliable lithium microreference electrodes for long-term in situ studies of lithium-based battery systems

    NARCIS (Netherlands)

    Zhou, J.; Notten, P.H.L.

    2004-01-01

    An in situ method to prepare lithium microreference electrodes has been developed. The microreference electrodes are made by electrochemical deposition of metallic lithium from both the positive and negative electrodes onto a copper wire positioned in-between the two Li-based battery electrodes. The

  18. Combustion synthesized nanocrystalline Li3V2(PO4)3/C cathode for lithium-ion batteries

    International Nuclear Information System (INIS)

    Nathiya, K.; Bhuvaneswari, D.; Gangulibabu; Kalaiselvi, N.

    2012-01-01

    Graphical abstract: Nanocrystalline Li 3 V 2 (PO 4 ) 3 /C compound has been synthesized using a novel corn assisted combustion (CAC) method, wherein the composite prepared at 850 °C is found to exhibit superior physical and electrochemical properties than the one synthesized at 800 °C (Fig. 1). Despite the charge disproportionation of V 4+ and a possible solid solution behavior of Li 3 V 2 (PO 4 ) 3 cathode upon insertion and de-insertion of Li + ions, the structural stability of the same is appreciable, even with the extraction of third lithium at 4.6 V (Fig. 2). An appreciable specific capacity of 174 mAh g −1 with an excellent columbic efficiency (99%) and better capacity retention upon high rate applications have been exhibited by Li 3 V 2 (PO 4 ) 3 /C cathode, thus demonstrating the feasibility of CAC method in preparing the title compound to best suit with the needs of lithium battery applications. Display Omitted Highlights: ► Novel corn assisted combustion method has been used to synthesize Li 3 V 2 (PO 4 ) 3 /C. ► Corn is a cheap and eco benign combustible fuel to facilitate CAC synthesis. ► Li 3 V 2 (PO 4 ) 3 /C exhibits an appreciable specific capacity of 174 mAh g −1 (C/10 rate). ► Currently observed columbic efficiency of 99% is better than the reported behavior. ► Suitability of Li 3 V 2 (PO 4 ) 3 /C cathode up to 10C rate is demonstrated. -- Abstract: Nanocrystalline Li 3 V 2 (PO 4 ) 3 /C composite synthesized using a novel corn assisted combustion method at 850 °C exhibits superior physical and electrochemical properties than the one synthesized at 800 °C. Despite the charge disproportionation of V 4+ and a possible solid solution behavior of Li 3 V 2 (PO 4 ) 3 cathode upon insertion and extraction of Li + ions, the structural stability of the same is appreciable, even with the extraction of third lithium at 4.6 V. An appreciable specific capacity of 174 mAh g −1 and better capacity retention upon high rate applications have been

  19. Coupling of Mechanical Behavior of Lithium Ion Cells to Electrochemical-Thermal (ECT) Models for Battery Crush

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Chao; Santhanagopalan, Shriram; Pesaran, Ahmad; Sahraei, Elham; Wierzbicki, Tom

    2016-06-14

    Vehicle crashes can lead to crushing of the battery, damaging lithium ion battery cells and causing local shorts, heat generation, and thermal runaway. Simulating all the physics and geometries at the same time is challenging and takes a lot of effort; thus, simplifications are needed. We developed a material model for simultaneously modeling the mechanical-electrochemical-thermal behavior, which predicted the electrical short, voltage drop, and thermal runaway behaviors followed by a mechanical abuse-induced short. The effect of short resistance on the battery cell performance was studied.

  20. Electrical conductivity and reaction with lithium of LiFe{sub 1-y}Mn{sub y}PO{sub 4} olivine-type cathode materials

    Energy Technology Data Exchange (ETDEWEB)

    Molenda, J.; Ojczyk, W.; Marzec, J. [Faculty of Materials Science and Ceramics, AGH University of Science and Technology, al. Mickiewicza 30, 30-059 Krakow (Poland)

    2007-12-06

    Structural, electrical and electrochemical properties of Mn-substituted phospho-olivines LiFe{sub 1-y}Mn{sub y}PO{sub 4} were investigated and compared to those of LiFePO{sub 4}. Rietvield refined XRD patterns taken in the course of delithiation process showed apparent difference between phase compositions of these cathode materials upon lithium extraction. Contrary to the LiFePO{sub 4} and LiMnPO{sub 4} compositions for which a two-phase mechanism of electrochemical lithium extraction/insertion is observed, in case of Mn-substituted LiFe{sub 1-y}Mn{sub y}PO{sub 4} samples a single-phase mechanism of deintercalation was observed in the studied range of lithium concentration. Electrochemical characterization of the cathode materials were performed in Li/Li{sup +}/Li{sub x}Fe{sub 1-y}Mn{sub y}PO{sub 4}-type cells for y = 0.0, 0.25, 0.55, 0.75 and 1.0 compositions. Voltammery studies showed low reversibility of the lithium extraction process in the high-voltage ''manganese'' range, while in the ''iron'' range the reversibility of lithium extraction is high. Impedance measurements of the LiFe{sub 1-y}Mn{sub y}PO{sub 4} cathode materials, which enabled separation of the ionic and electronic components of their entire electrical conductivity, showed distinct influence of Mn content on the electronic part of conductivity. EIS measurements performed at different states of cell charge revealed that the charge-transfer impedance in Li{sub x}Fe{sub 1-y}Mn{sub y}PO{sub 4} is much lower than that of Li{sub x}FePO{sub 4}. (author)

  1. Effect of oxide ion concentration on the electrochemical oxidation of carbon in molten LiCl

    International Nuclear Information System (INIS)

    Yun, J. W.; Choi, I. K.; Park, Y. S.; Kim, W. H.

    2001-01-01

    The continuous measurement of lithium oxide concentration was required in DOR (Direct Oxide Reduction) process, which converts spent nuclear fuel to metal form, for the reactivity monitor and effective control of the process. The concentration of lithium oxide was measured by the electrochemical method, which was based on the phenomenon that carbon atoms of glassy carbon electrode electrochemically react with oxygen ions of lithium oxide in molten LiCl medium. From the results of electrode polarization experiments, the trend of oxidation rate of carbon atoms was classified into two different regions, which were proportional and non-proportional ones, dependent on the amount of lithium oxide. Below about 2.5 wt % Li 2 O, as the carbon atom ionization rate was fast enough for reacting with diffusing lithium oxide to the surface of carbon electrode. In this concentration range, the oxidation rate of carbon atoms was controlled by the diffusion of lithium oxide, and the concentration of lithium oxide could be measured by electrochemical method. But, above 2.5 wt % Li 2 O, the oxidation rate of carbon atoms was controlled by the applied electrochemical potential, because the carbon atom ionization rate was suppressed by the huge amounts of diffusing Li 2 O. Above this concentration, the electrochemical method was not applicable to determine the concentration of lithium oxide

  2. Enhanced electrochemical properties of vanadium-doped titanium niobate as a new anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Wen, Xiaoyan; Ma, Chenxiang; Du, Chenqiang; Liu, Jie; Zhang, Xinhe; Qu, Deyang; Tang, Zhiyuan

    2015-01-01

    The Vanadium-doped TiNb 2 O 7 (TNO) samples have been investigated as novel anode active materials for application in lithium-ion batteries. The samples are characterized by X-ray diffraction patterns (XRD), raman spectrum, scanning electron microscopy (SEM), transmission electron microscopy (TEM), galvanostatic charge-discharge tests, and cyclic voltammetry (CV) tests. The XRD results indicate that V-doping expands the lattice parameters of TiNb 2 O 7 samples and facilitates the enhanced lithium ion diffusion. SEM and TEM results show that lattice expansion caused by V-doping doesn’t significantly change the particle size distribution of TiNb 2 O 7 samples. The electrochemical measurements indicate that the TiNb 1.98 V 0.02 O 7 anode material displays a highly reversible capacity and excellent cycling stability. The initial discharge capacities of TiNb 1.98 V 0.02 O 7 are 298.48 mAh g −1 and 171.99 mAh g −1 at 0.3C and 10C, respectively, indicating that the TiNb 1.98 V 0.02 O 7 material can be utilized as a promising anode material for lithium-ion batteries.

  3. Electrochemical performance of arc-produced carbon nanotubes as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Yang, Shubin; Song, Huaihe; Chen, Xiaohong; Okotrub, A.V.; Bulusheva, L.G.

    2007-01-01

    The effects of etching process on the morphology, structure and electrochemical performance of arc-produced multiwalled carbon nanotubes (CNTs) as anode material for lithium-ion batteries were systematically investigated by TEM and a variety of electrochemical testing techniques. It was found that the etched CNTs exhibited four times higher reversible capacity than that of raw CNTs, and possessed excellent cyclability with almost 100% capacity retention after 30 cycles. The kinetic properties of three kinds of CNTs electrodes involving the pristine (CNTs-1), etched (CNTs-2) as well as etch-carbonized samples (CNTs-3) were characterized via ac impedance measurement. It was indicated that, after 30 cycles the exchange current density i 0 of etched CNTs ((7.6-7.8) x 10 -3 A cm -2 ) was higher than that of the raw CNTs (5.9 x 10 -3 A cm -2 ), suggesting the electrochemical activity of CNTs was enhanced by the etching treatment. The storage characteristics of the CNTs electrodes at room temperature and 50 o C were particularly compared. It was found that the film resistance on CNTs electrode generally tended to become large with the elongation of storage time, especially storage at high temperature. In comparison with CNTs-1 and CNTs-3, CNTs-2 exhibited more distinctly increase of film resistance, which is related with the surface properties

  4. Sulfur nanocrystals anchored graphene composite with highly improved electrochemical performance for lithium-sulfur batteries

    Science.gov (United States)

    Zhang, Jun; Dong, Zimin; Wang, Xiuli; Zhao, Xuyang; Tu, Jiangping; Su, Qingmei; Du, Gaohui

    2014-12-01

    Two kinds of graphene-sulfur composites with 50 wt% of sulfur are prepared using hydrothermal method and thermal mixing, respectively. Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray Spectra mapping show that sulfur nanocrystals with size of ∼5 nm dispersed on graphene sheets homogeneously for the sample prepared by hydrothermal method (NanoS@G). While for the thermal mixed graphene-sulfur composite (S-G mixture), sulfur shows larger and uneven size (50-200 nm). X-ray Photoelectron Spectra (XPS) reveals the strong chemical bonding between the sulfur nanocrystals and graphene. Comparing with the S-G mixture, the NanoS@G composite shows highly improved electrochemical performance as cathode for lithium-sulfur (Li-S) battery. The NanoS@G composite delivers an initial capacity of 1400 mAh g-1 with the sulfur utilization of 83.7% at a current density of 335 mA g-1. The capacity keeps above 720 mAh g-1 over 100 cycles. The strong adherence of the sulfur nanocrystals on graphene immobilizes sulfur and polysulfides species and suppressed the "shuttle effect", resulting higher coulombic efficiency and better capacity retention. Electrochemical impedance also suggests that the strong bonding enabled rapid electronic/ionic transport and improved electrochemical kinetics, therefore good rate capability is obtained. These results demonstrate that the NanoS@G composite is a very promising candidate for high-performance Li-S batteries.

  5. Silver-coated LiVPO4F composite with improved electrochemical performance as cathode material for lithium-ion batteries

    Science.gov (United States)

    Yang, Bo; Yang, Lin

    2015-12-01

    Nano-structured LiVPO4F/Ag composite cathode material has been successfully synthesized via a sol-gel route. The structural and physical properties, as well as the electrochemical performance of the material are compared with those of the pristine LiVPO4F. X-ray diffraction (XRD) and scanning electron microscopy (SEM) reveal that Ag particles are uniformly dispersed on the surface of LiVPO4F without destroying the crystal structure of the bulk material. An analysis of the electrochemical measurements show that the Ag-modified LiVPO4F material exhibits high discharge capacity, good cycle performance (108.5 mAh g-1 after 50th cycles at 0.1 C, 93% of initial discharge capacity) and excellent rate behavior (81.8 mAh g-1 for initial discharge capacity at 5 C). The electrochemical impedance spectroscopy (EIS) results reveal that the adding of Ag decreases the charge-transfer resistance (Rct) of LiVPO4F cathode. This study demonstrates that Ag-coating is a promising way to improve the electrochemical performance of the pristine LiVPO4F for lithium-ion batteries cathode material.

  6. Effect of Ce addition on the mechanical and electrochemical properties of a lithium battery shell alloy

    International Nuclear Information System (INIS)

    Zhang, Junchao; Ding, Dongyan; Xu, Xinglong; Gao, Yongjin; Chen, Guozhen; Chen, Weigao; You, Xiaohua; Huang, Yuanwei; Tang, Jinsong

    2014-01-01

    Highlights: • Fabrication of Ce-free and Ce-containing Al–Cu–Mn–Fe–Mg alloy. • TEM, tensile and electrochemical characterization of the alloys. • Ce element greatly affects the precipitation of the alloy. • Ce element had great impact on the tensile strength and corrosion potential of the alloys. - Abstract: Due to severe application environment lithium battery shell of new-energy automotives requires increasing demands for using high performance aluminum alloys. In the present work, effect of Ce addition on the microstructure, tensile and electrochemical properties of an Al–Cu–Mn–Mg–Fe alloy were investigated through using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile tests and electrochemical tests. The experimental results indicated that the addition of Ce element could promote the precipitation of second phases. With addition of 0.36% Ce, high melting point Al 8 Cu 4 Ce phase and many Al 20 Cu 2 Mn 3 particles could be found. In addition, the precipitation of conventionally dominant phase of Al 2 Cu could be suppressed in alloy. The Ce addition was found to result in enhanced tensile strength and improved corrosion resistance

  7. Effect of Ce addition on the mechanical and electrochemical properties of a lithium battery shell alloy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Junchao [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Ding, Dongyan, E-mail: dyding@sjtu.edu.cn [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Xu, Xinglong [School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Gao, Yongjin; Chen, Guozhen; Chen, Weigao; You, Xiaohua [Huafon NLM Al Co., Ltd, Shanghai 201506 (China); Huang, Yuanwei; Tang, Jinsong [Shanghai Huafon Materials Technology Institute, Shanghai 201203 (China)

    2014-12-25

    Highlights: • Fabrication of Ce-free and Ce-containing Al–Cu–Mn–Fe–Mg alloy. • TEM, tensile and electrochemical characterization of the alloys. • Ce element greatly affects the precipitation of the alloy. • Ce element had great impact on the tensile strength and corrosion potential of the alloys. - Abstract: Due to severe application environment lithium battery shell of new-energy automotives requires increasing demands for using high performance aluminum alloys. In the present work, effect of Ce addition on the microstructure, tensile and electrochemical properties of an Al–Cu–Mn–Mg–Fe alloy were investigated through using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile tests and electrochemical tests. The experimental results indicated that the addition of Ce element could promote the precipitation of second phases. With addition of 0.36% Ce, high melting point Al{sub 8}Cu{sub 4}Ce phase and many Al{sub 20}Cu{sub 2}Mn{sub 3} particles could be found. In addition, the precipitation of conventionally dominant phase of Al{sub 2}Cu could be suppressed in alloy. The Ce addition was found to result in enhanced tensile strength and improved corrosion resistance.

  8. High-performance lithium-rich layered oxide materials: Effects of chelating agents on microstructure and electrochemical properties

    International Nuclear Information System (INIS)

    Li, Lingjun; Xu, Ming; Chen, Zhaoyong; Zhou, Xiang; Zhang, Qiaobao; Zhu, Huali; Wu, Chun; Zhang, Kaili

    2015-01-01

    The mechanisms and effects of three typical chelating agents, namely glucose, citric acid and sucrose on the sol-gel synthesis process, electrochemical degradation and structural evolution of 0.5Li 2 MnO 3 ·0.5LiNi 0.5 Co 0.2 Mn 0.3 O 2 (LLMO) materials are systematically compared for the first time. X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and high-resolution transmission electron microscopy analysis indicate that the sample synthesized from sucrose owns well structure, homogenous distribution, low Ni 3+ concentration and good surface structural stability during cycling, respectively. Electrochemical tests further prove that the LLMO material obtained from sucrose maintains 258.4 mAh g −1 with 94.8% capacity retention after 100 cycles at 0.2 C. The superior electrochemical performance can be ascribed to the exceptional complexing mechanism of sucrose, compared to those of the glucose and citric acid. Namely, one mole sucrose can be hydrolyzed into two different monosaccharides and further chelates three M (Li, Ni, Co and Mn) ions to form a more uniform ion-chelated matrix during sol-gel process. This discovery is an important step towards understanding the selection criterion of chelating agents for sol-gel method, that chelating agent with excellent complexing capability is beneficial to the distribution, structural stability and electrochemical properties of advanced lithium-rich layered materials

  9. Hydrogen-bonding-mediated synthesis of atomically thin TiO2 films with exposed (001) facets and applications in fast lithium insertion/extraction.

    Science.gov (United States)

    Zhang, Hongye; Yang, Zhenzhen; Gan, Wei; Zhao, Yanfei; Yu, Bo; Xu, Huanjun; Ma, Zhishuang; Hao, Leiduan; Chen, Dechao; Miao, Shiding; Liu, Zhimin

    2015-10-05

    Ultrathin two-dimensional (2D) crystalline materials show high specific surface area (SA) of high energy (HE) facets, imparting a significant improvement in their performances. Herein we report a novel route to synthesize TiO2 nanofilms (NFs) with atomic thickness (lithium insertion/extraction, demonstrating foreseeable applications in the energy storage. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Preparation and electrochemical performance of sulfur-alumina cathode material for lithium-sulfur batteries

    International Nuclear Information System (INIS)

    Dong, Kang; Wang, Shengping; Zhang, Hanyu; Wu, Jinping

    2013-01-01

    Highlights: ► Micron-sized alumina was synthesized as adsorbent for lithium-sulfur batteries. ► Sulfur-alumina material was synthesized via crystallizing nucleation. ► The Al 2 O 3 can provide surface area for the deposition of Li 2 S and Li 2 S 2 . ► The discharge capacity of the battery is improved during the first several cycles. - Abstract: Nano-sized sulfur particles exhibiting good adhesion with conducting acetylene black and alumina composite materials were synthesized by means of an evaporated solvent and a concentrated crystallization method for use as the cathodes of lithium-sulfur batteries. The composites were characterized and examined by X-ray diffraction, environmental scanning electron microscopy and electrochemical methods, such as cyclic voltammetry, electrical impedance spectroscopy and charge–discharge tests. Micron-sized flaky alumina was employed as an adsorbent for the cathode material. The initial discharge capacity of the cathode with the added alumina was 1171 mAh g −1 , and the remaining capacity was 585 mAh g −1 after 50 cycles at 0.25 mA cm −2 . Compared with bare sulfur electrodes, the electrodes containing alumina showed an obviously superior cycle performance, confirming that alumina can contribute to reducing the dissolution of polysulfides into electrolytes during the sulfur charge–discharge process

  11. Status of the DOE battery and electrochemical technology program. III

    International Nuclear Information System (INIS)

    Roberts, R.

    1982-02-01

    This report reviews the status of the Department of Energy Subelement on Electrochemical Storage Systems. It emphasizes material presented at the Fourth US Department of Energy Battery and Electrochemical Contractors' Conference, held June 2-4, 1981. The conference stressed secondary batteries, however, the aluminum/air mechanically rechargeable battery and selected topics on industrial electrochemical processes were included. The potential contributions of the battery and electrochemical technology efforts to supported technologies: electric vehicles, solar electric systems, and energy conservation in industrial electrochemical processes, are reviewed. The analyses of the potential impact of these systems on energy technologies as the basis for selecting specific battery systems for investigation are noted. The battery systems in the research, development, and demonstration phase discussed include: aqueous mobile batteries (near term) - lead-acid, iron/nickel-oxide, zinc/nickel-oxide; advanced batteries - aluminum/air, iron/air, zinc/bromine, zinc/ferricyanide, chromous/ferric, lithium/metal sulfide, sodium/sulfur; and exploratory batteries - lithium organic electrolyte, lithium/polymer electrolyte, sodium/sulfur (IV) chloroaluminate, calcium/iron disulfide, lithium/solid electrolyte. Supporting research on electrode reactions, cell performance modeling, new battery materials, ionic conducting solid electrolytes, and electrocatalysis is reviewed. Potential energy saving processes for the electrowinning of aluminum and zinc, and for the electrosynthesis of inorganic and organic compounds are included

  12. Unique interconnected graphene/SnO2 nanoparticle spherical multilayers for lithium-ion battery applications.

    Science.gov (United States)

    Shao, Qingguo; Tang, Jie; Sun, Yige; Li, Jing; Zhang, Kun; Yuan, Jinshi; Zhu, Da-Ming; Qin, Lu-Chang

    2017-03-30

    We have designed and synthesized a unique structured graphene/SnO 2 composite, where SnO 2 nanoparticles are inserted in between interconnected graphene sheets which form hollow spherical multilayers. The hollow spherical multilayered structure provides much flexibility to accommodate the configuration and volume changes of SnO 2 in the material. When it is used as an anode material for lithium-ion batteries, such a novel nanostructure can not only provide a stable conductive matrix and suppress the mechanical stress, but also eliminate the need of any binders for constructing electrodes. Electrochemical tests show that the unique graphene/SnO 2 composite electrode as designed could exhibit a large reversible capacity over 1000 mA h g -1 and long cycling life with 88% retention after 100 cycles. These results indicate the great potential of the composite for being used as a high performance anode material for lithium-ion batteries.

  13. Electrochemical characteristics of polyacetylene in organic electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Padula, A.; Scrosati, B.

    1985-01-15

    The characteristics of the electrochemical doping process of polyacetylene have been investigated in lithium cells using lithium perchlorate in propylene carbonate as electrolytic solution. The kinetics of this process are controlled by the diffusion of the dopant species throughout the polymer. Therefore, polyacetylene samples with a highly porous, extended surface should be selected for the development of efficient, rechargeable lithium batteries. In line with this, we have considered foam-type polyacetylene electrodes which have a lower density than the 'classical' Shirakawa-type film electrodes. The electrochemical behaviour of the polyacetylene foam samples has been examined by cyclic voltametry response and constant current, charge-discharge cycles. The results are described in this work.

  14. Synthesis of TiO2 by electrochemical method from TiCl4 solution as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Nur, Adrian; Purwanto, Agus; Jumari, Arif; Dyartanti, Endah R.; Sari, Sifa Dian Permata; Hanifah, Ita Nur

    2016-01-01

    Metal oxide combined with graphite becomes interesting composition. TiO 2 is a good candidate for Li ion battery anode because of cost, availability of sufficient materials, and environmentally friendly. TiO 2 gravimetric capacity varied within a fairly wide range. TiO 2 crystals form highly depends on the synthesis method used. The electrochemical method is beginning to emerge as a valuable option for preparing TiO 2 powders. Using the electrochemical method, the particle can easily be controlled by simply adjusting the imposed current or potential to the system. In this work, the effects of some key parameters of the electrosynthesis on the formation of TiO 2 have been investigated. The combination of graphite and TiO 2 particle has also been studied for lithium-ion batteries. The homogeneous solution for the electrosynthesis of TiO 2 powders was TiCl 4 in ethanol solution. The electrolysis was carried out in an electrochemical cell consisting of two carbon electrodes with dimensions of (5 × 2) cm. The electrodes were set parallel with a distance of 2.6 cm between the electrodes and immersed in the electrolytic solution at a depth of 2 cm. The electrodes were connected to the positive and negative terminals of a DC power supply. The electrosynthesis was performed galvanostatically at 0.5 to 2.5 hours and voltages were varied from 8 to 12 V under constant stirring at room temperature. The resulted suspension was aged at 48 hrs, filtered, dried directly in an oven at 150°C for 2 hrs, washed 2 times, and dried again 60 °C for 6 hrs. The particle product has been used to lithium-ion battery as anode. Synthesis of TiO 2 particle by electrochemical method at 10 V for 1 to 2.5 hrs resulted anatase and rutile phase

  15. Electrochemical capacitor behavior of copper sulfide (CuS) nanoplatelets

    Energy Technology Data Exchange (ETDEWEB)

    Justin Raj, C.; Kim, Byung Chul; Cho, Won-Je; Lee, Won-Gil; Seo, Yongseong; Yu, Kook-Hyun, E-mail: yukook@dongguk.edu

    2014-02-15

    Highlights: • The electrochemical supercapacitor electrode was fabricated using CuS nanoplatelets. • CuS electrodes shows better electrochemical properties in aqueous LiClO{sub 4} electrolyte. • The heat treated CuS electrode shows an excellent pseudocapacitance performance than bare CuS electrode. -- Abstract: Copper sulfide (CuS) nanoplatelets have been fabricated by simple low temperature chemical bath deposition technique for electrochemical supercapacitor electrodes. The morphology and structural properties of the electrodes were analyzed using scanning electron microscopy and X-ray diffraction. The effect of heat treatment on electrochemical properties of CuS electrodes were examined by cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge/discharge tests. Results show that bare and heat treated CuS has pseudocapacitive characteristic within the potential range of −0.6 to 0.3 V (vs. Ag/AgCl) in aqueous 1 M LiClO{sub 4} solution. The pseudocapacitance is induced mainly by lithium ions insertion/extraction with the CuS electrodes. The specific capacitance of 72.85 F g{sup −1} was delivered by heat treated CuS film at a scan rate of 5 mV s{sup −1} with an energy and power density of 6.23 W h kg{sup −1} and 1.75 kW kg{sup −1} at 3 Ag{sup −1} constant discharge current which is comparatively higher than that of as deposited CuS electrode.

  16. Electrochemical performance of LiMSnO4 (M=Fe, In) phases with ramsdellite structure as anodes for lithium batteries

    International Nuclear Information System (INIS)

    Satya Kishore, M.V.; Varadaraju, U.V.; Raveau, B.

    2004-01-01

    LiMSnO 4 (M=Fe, In) compounds were synthesized by high temperature solid-state reaction method and the electrochemical studies were carried out vs. lithium metal. Lithium is reversibly intercalated and deintercalated in LiFeSnO 4 with a constant capacity of ∼90mAh/g. In situ X-ray diffraction data show that ramsdellite structure is stable for lithium intercalation and deintercalation in LiFeSnO 4 . Galvanostatic discharge/charge of LiFeSnO 4 in the voltage window 0.05-2.0V shows a reversible capacity of ∼100mAh/g. The observed capacity in LiFeSnO 4 is due to the two processes involving alloying/dealloying of Li 4.4 Sn and formation/decomposition of Li 2 O. In contrast, the new isotypic oxide LiInSnO 4 does not exhibit any lithium intercalation due to the absence of mixed valence for indium. Its reversible capacity is strongly dependent on the voltage window. LiInSnO 4 exhibits severe capacity fading on cycling in the voltage window 0.05-2.0V, but shows a stable capacity of ∼90mAh/g in the voltage range 0.75-2.0V

  17. New Insights on the Structure of Electrochemically Deposited Lithium Metal and Its Solid Electrolyte Interphases via Cryogenic TEM

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xuefeng; Zhang, Minghao; Alvarado, Judith; Wang, Shen; Sina, Mahsa; Lu, Bingyu; Bouwer, James; Xu, Wu [Energy; Xiao, Jie [Energy; Zhang, Ji-Guang [Energy; Liu, Jun [Energy; Meng, Ying Shirley

    2017-11-02

    Lithium metal has been considered as the “holy grail” anode material for rechargeable batteries though the dendritic growth and low Coulombic efficiency (CE) have crippled its practical use for decades. Its high chemical reactivity and low stability make it difficult to explore the intrinsic chemical and physical properties of the electrochemically deposited lithium (EDLi) and its accompanied solid electrolyte interphase (SEI). To prevent the dendritic growth and enhance the electrochemical reversibility, it is crucial to understand the nano- and meso- structures of EDLi. However, Li metal is very sensitive to beam damage and has low contrast for commonly used characterization techniques such as electron microscopy. Inspired by biological imaging techniques, this work demonstrates the power of cryogenic (cryo)- electron microscopy to reveal the detailed structure of EDLi and the SEI composition at the nano scale while minimizing beam damage during imaging. Surprisingly, the results show that the nucleation dominated EDLi (five minutes at 0.5 mA cm-2) is amorphous while there is some crystalline LiF present in the SEI. The EDLi grown from various electrolytes with different additives exhibits distinctive surface properties. Consequently, these results highlight the importance of the SEI and its relationship with the CE. Our findings not only illustrate the capabilities of cryogenic microscopy for beam (thermal)-sensitive materials, but it yields crucial structural information of the EDLi evolution with and without electrolyte additives.

  18. Raman spectral and electrochemical studies of lithium/electrolyte interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Odziemkowski, M

    1922-01-01

    Cyclic voltammetry, corrosion potential-time transients and Normal Raman spectroscopy have been employed to characterize the lithium-lithium salt, organic solvent, interfacial region. An in-situ cutting technique was developed to expose lithium metal. In-situ optical and ex-situ scanning electron microscopy (SEM) have been used to examine the morphology of the lithium electrode surface during exposure at open circuit and after anodic polarization. The main reaction product detected by in-situ Raman spectroscopy in the system/lithium/LiAsF[sub 6], tetrahydrofuran (THF) electrolyte was polytetrahydrofuran (PTHF). The conditions for the polymerization reaction in the presence of lithium metal have been determined. Tetrahydrofuran (THF) decomposition reaction mechanisms are discussed. Decomposition reaction products have been determined as arsenic (II) oxide, As[sub 2]O[sub 3] (arsenolite) and arsenious oxyfluoride AsF[sub 2]-O-AsF[sub 2]. Potentiodynamic polarization measurements revealed a substantial shift of the corrosion potential towards positive values and only a moderate increase of anodic dissolution current for in-situ cut lithium metal. Corrosion potential-time merits have been measured. The following electrolytes have been investigated: LiAsF[sub 6], LiPF[sub 6], LiClO[sub 4], and Li(CF[sub 3]SO[sub 2])[sub 2]N in THF, 2Me-THF, and propylene carbonate (PC). The transients permit the ranking of the reactivity of the electrolytes. These measurements have shed light on understanding the stability of various stability and and solvents in contact with lithium. Compared to purified electrolytes, small amounts of water shift the corrosion potential towards even more positive values. Intensive anodic cycling of a Li electrode in unpurified LiAsF[sub 6]/THF electrolyte leads to the breakdown of a surface film/films. While at the open circuit potential (OCP), water in this same electrolyte leads to crack formation in the bulk lithium electrode.

  19. Vinylene carbonate and tris(trimethylsilyl) phosphite hybrid additives to improve the electrochemical performance of spinel lithium manganese oxide/graphite cells at 60 °C

    International Nuclear Information System (INIS)

    Koo, Bonjae; Lee, Jeongmin; Lee, Yongwon; Kim, Jun Ki; Choi, Nam-Soon

    2015-01-01

    Highlights: •The combination of tris(trimethylsilyl) phosphite and vinylene carbonate improves the electrochemical performance of lithium manganese oxide/graphite cells at 60 °C. •Removal of hydrogen fluoride and water by tris(trimethylsilyl) phosphite suppresses manganese dissolution from lithium manganese oxide. -- Abstract: The organophosphorus compounds tris(trimethylsilyl) phosphite (TMSP) and vinylene carbonate (VC) have been considered for use as functional additives to improve the electrochemical performance of Li 1.1 Mn 1.86 Mg 0.04 O 4 (LMO)/graphite full cells. Our investigation reveals that the combination of VC and TMSP as additives enhances the cycling properties and storage performance of full cells at 60 °C. The unique functions of the TMSP additive in the VC electrolyte are investigated via ex situ X-ray photoelectron spectroscopy (XPS) and 19 F nuclear magnetic resonance (NMR) measurements. The TMSP additive effectively eliminates trace water and hydrogen fluoride (HF) and produces a protective film on the LMO cathode that alleviates manganese dissolution at 60 °C

  20. Conductivity and electrochemical performance of LiFePO4 slurry in the lithium slurry battery

    Science.gov (United States)

    Feng, Caimei; Chen, Yongchong; Liu, Dandan; Zhang, Ping

    2017-06-01

    Lithium slurry battery is a new type of energy storage technique which uses the slurry of solid active materials, conductive additions and liquid electrolyte as the electrode. The proportion of conductive addition and the active material has significant influence on the conductivity and electrochemical performance of the slurry electrode. In the present work, slurries with different volume ratios of LiFePO4 (LFP) and Ketjenblack (KB) were investigated by the electrochemical workstation and charge-discharge testing system (vs. Li/Li+). Results show that the conductivity of the slurry increases linearly with the addition of KB, and the measured specific capacity of the slurry reaches its theoretical value when the volume ratio of KB to LFP is around 0.2. Based on this ratio, a slurry battery with higher loading of LFP (19.1 wt.% in the slurry) was tested, and a specific capacity of 165 mAh/g at 0.2 mA/cm2 and 102 mAh/g at 5 mA/cm2 was obtained for LFP.

  1. Lithium-deficient Li YMn2O4 spinels (0.9 ≤ Y < 1): Lithium content, synthesis temperature, thermal behaviour and electrochemical properties

    International Nuclear Information System (INIS)

    Pascual, Laura; Perez-Revenga, M. Luz; Rojas, Rosa M.; Rojo, Jose M.; Amarilla, J. Manuel

    2006-01-01

    Lithium-deficient Li Y Mn 2 O 4 spinels (LD-Li Y Mn 2 O 4 ) with nominal composition (0.9 ≤ Y 2 O 3 and LiNO 3 at temperatures ranging from 700 deg. C to 850 deg. C. X-ray diffraction data show that LD-Li Y Mn 2 O 4 spinels are obtained as single phases in the range Y = 0.975-1 at 700 deg. C and 750 deg. C. Morphological characterization by transmission electron microscopy shows that the particle size of LD-Li Y Mn 2 O 4 spinels increases on decreasing the Li-content. The influence of the Li-content and the synthesis temperature on the thermal and electrochemical behaviours has been systematically studied. Thermal analysis studies indicate that the temperature of the first thermal effect in the differential thermal analysis (DTA)/thermogravimetric (TG) curves, T C1 , linearly increases on decreasing the Li-content. The electrochemical properties of LD-Li Y Mn 2 O 4 spinels, determined by galvanostatic cycling, notably change with the synthesis conditions. So, the first discharge capacity, Q disch. , at C rate increases on rising the Li-content and the synthesis temperature. The sample Li 0.975 Mn 2 O 4 synthesized at 700 deg. C has a Q disch. = 123 mAh g -1 and a capacity retention of 99.77% per cycle. This LD-Li Y Mn 2 O 4 sample had the best electrochemical characteristics of the series

  2. Lithium-aluminum-iron electrode composition

    Science.gov (United States)

    Kaun, Thomas D.

    1979-01-01

    A negative electrode composition is presented for use in a secondary electrochemical cell. The cell also includes an electrolyte with lithium ions such as a molten salt of alkali metal halides or alkaline earth metal halides that can be used in high-temperature cells. The cell's positive electrode contains a a chalcogen or a metal chalcogenide as the active electrode material. The negative electrode composition includes up to 50 atom percent lithium as the active electrode constituent in an alloy of aluminum-iron. Various binary and ternary intermetallic phases of lithium, aluminum and iron are formed. The lithium within the intermetallic phase of Al.sub.5 Fe.sub.2 exhibits increased activity over that of lithium within a lithium-aluminum alloy to provide an increased cell potential of up to about 0.25 volt.

  3. Low hydrogen containing amorphous carbon films - Growth and electrochemical properties as lithium battery anodes

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, V.; Masarapu, Charan; Wei, Bingqing [Department of Mechanical Engineering, University of Delaware, 130 Academy Street, Newark, DE 19716 (United States); Karabacak, Tansel [Department of Applied Science, University of Arkansas at Little Rock, 2801 South University Avenue, Little Rock, AR 72204 (United States); Teki, Ranganath [Department of Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States); Lu, Toh-Ming [Department of Physics, Applied Physics, and Astronomy, Rensselaer Polytechnic Institute, Troy, NY 12180 (United States)

    2010-04-02

    Amorphous carbon films were deposited successfully on Cu foils by DC magnetron sputtering technique. Electrochemical performance of the film as lithium battery anode was evaluated across Li metal at 0.2 C rate in a non-aqueous electrolyte. The discharge curves showed unusually low irreversible capacity in the first cycle with a reversible capacity of {proportional_to}810 mAh g{sup -1}, which is at least 2 times higher than that of graphitic carbon. For the first time we report here an amorphous carbon showing such a high reversibility in the first cycle, which is very much limited to the graphitic carbon. The deposited films were extensively characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and step profilometer for the structural and surface properties. The hydrogen content of the synthesized films was studied using residual gas analysis (RGA). The low hydrogen content and the low specific surface area of the synthesized amorphous carbon film are considered responsible for such a high first cycle columbic efficiency. The growth mechanism and the reasons for enhanced electrochemical performance of the carbon films are discussed. (author)

  4. Low hydrogen containing amorphous carbon films-Growth and electrochemical properties as lithium battery anodes

    Science.gov (United States)

    Subramanian, V.; Karabacak, Tansel; Masarapu, Charan; Teki, Ranganath; Lu, Toh-Ming; Wei, Bingqing

    Amorphous carbon films were deposited successfully on Cu foils by DC magnetron sputtering technique. Electrochemical performance of the film as lithium battery anode was evaluated across Li metal at 0.2 C rate in a non-aqueous electrolyte. The discharge curves showed unusually low irreversible capacity in the first cycle with a reversible capacity of ∼810 mAh g -1, which is at least 2 times higher than that of graphitic carbon. For the first time we report here an amorphous carbon showing such a high reversibility in the first cycle, which is very much limited to the graphitic carbon. The deposited films were extensively characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM) and step profilometer for the structural and surface properties. The hydrogen content of the synthesized films was studied using residual gas analysis (RGA). The low hydrogen content and the low specific surface area of the synthesized amorphous carbon film are considered responsible for such a high first cycle columbic efficiency. The growth mechanism and the reasons for enhanced electrochemical performance of the carbon films are discussed.

  5. Relevant Features of a Triethylene Glycol Dimethyl Ether-Based Electrolyte for Application in Lithium Battery.

    Science.gov (United States)

    Carbone, Lorenzo; Di Lecce, Daniele; Gobet, Mallory; Munoz, Stephen; Devany, Matthew; Greenbaum, Steve; Hassoun, Jusef

    2017-05-24

    Triethylene glycol dimethyl ether (TREGDME) dissolving lithium trifluoromethanesulfonate (LiCF 3 SO 3 ) is studied as a suitable electrolyte medium for lithium battery. Thermal and rheological characteristics, transport properties of the dissolved species, and the electrochemical behavior in lithium cell represent the most relevant investigated properties of the new electrolyte. The self-diffusion coefficients, the lithium transference numbers, the ionic conductivity, and the ion association degree of the solution are determined by pulse field gradient nuclear magnetic resonance and electrochemical impedance spectroscopy. The study sheds light on the determinant role of the lithium nitrate (LiNO 3 ) addition for allowing cell operation by improving the electrode/electrolyte interfaces and widening the voltage stability window. Accordingly, an electrochemical activation procedure of the Li/LiFePO 4 cell using the upgraded electrolyte leads to the formation of stable interfaces at the electrodes surface as clearly evidenced by cyclic voltammetry, impedance spectroscopy, and ex situ scanning electron microscopy. Therefore, the lithium battery employing the TREGDME-LiCF 3 SO 3 -LiNO 3 solution shows a stable galvanostatic cycling, a high efficiency, and a notable rate capability upon the electrochemical conditions adopted herein.

  6. Characterization and electrochemical performance of lithium-active titanium dioxide inlaid LiNi{sub 0.5}Co{sub 0.2}Mn{sub 0.3}O{sub 2} material prepared by lithium residue-assisted method

    Energy Technology Data Exchange (ETDEWEB)

    Li, Lingjun [School of Physics and Electronic Science, Changsha University of Science and Technology, Changsha 410114 (China); Department of Mechanical and Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon (Hong Kong); Chen, Zhaoyong, E-mail: csullj@hotmail.com [School of Physics and Electronic Science, Changsha University of Science and Technology, Changsha 410114 (China); Song, Liubin [Hunan Provincial Key Laboratory of Materials Protection for Electric Power and Transportation, School of Chemistry and Biological Engineering, Changsha University of Science and Technology, Changsha 410004, Hunan (China); Xu, Ming; Zhu, Huali; Gong, Li [School of Physics and Electronic Science, Changsha University of Science and Technology, Changsha 410114 (China); Zhang, Kaili, E-mail: kaizhang@cityu.edu.hk [Department of Mechanical and Biomedical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon (Hong Kong)

    2015-07-25

    Highlights: • LiTiO{sub 2}-inlaid LiNi{sub 0.5}Co{sub 0.2}Mn{sub 0.3}O{sub 2} is prepared by lithium residue-assisted method. • The unique inlaid architecture inherits the advantages of coating and doping. • LiTiO{sub 2} inlaying enhances the pristine at high cyclability and rate properties. • Excess LiTiO{sub 2} modification results in low Li{sup +} diffusion coefficient. • The 3 mol% LiTiO{sub 2} inlaid sample exhibits the best electrochemical performance. - Abstract: The lithium residues are consumed as raw materials to in-situ synthesize the LiTiO{sub 2}-inlaid LiNi{sub 0.5}Co{sub 0.2}Mn{sub 0.3}O{sub 2} composites. The effects of various LiTiO{sub 2} contents on the morphology, structure, and electrochemical properties of LiNi{sub 0.5}Co{sub 0.2}Mn{sub 0.3}O{sub 2} materials are investigated in detail. Energy dispersive spectrometer mapping, high-resolution transmission electron microscopy and fast Fourier transform analysis confirm that the spherical particles of LiNi{sub 0.5}Co{sub 0.2}Mn{sub 0.3}O{sub 2} are completely coated by crystalline LiTiO{sub 2} phase; X-ray diffraction, cross-section SEM and corresponding EDS results indicate that Ti ions are also doped into the bulk LiNi{sub 0.5}Co{sub 0.2}Mn{sub 0.3}O{sub 2} with gradient distribution. Electrochemical tests show that the LiTiO{sub 2}-inlaid samples exhibit excellent reversible capacity, enhanced cyclability, superior lithium diffusion coefficient and rate properties. Specially, the 3 mol% LiTiO{sub 2} inlaid sample maintains 153.7 mA h g{sup −1} with 94.4% capacity retention after 100 cycles between 2.7–4.4 V at 1 C, take 30% advantage than that of the pristine one (118.2 mA h g{sup −1}). This improvement can be attributed to the removal of lithium residues and suitable LiTiO{sub 2} inlaying. The absence of lithium residue is helpful to retard the decomposition of LiPF{sub 6}. While, suitable LiTiO{sub 2} inlaying can protect the bulk from directly contacting the electrolyte

  7. Strategies to optimize lithium-ion supercapacitors achieving high-performance: Cathode configurations, lithium loadings on anode, and types of separator

    Science.gov (United States)

    Cao, Wanjun; Li, Yangxing; Fitch, Brian; Shih, Jonathan; Doung, Tien; Zheng, Jim

    2014-12-01

    The Li-ion capacitor (LIC) is composed of a lithium-doped carbon anode and an activated carbon cathode, which is a half Li-ion battery (LIB) and a half electrochemical double-layer capacitor (EDLC). LICs can achieve much more energy density than EDLC without sacrificing the high power performance advantage of capacitors over batteries. LIC pouch cells were assembled using activated carbon (AC) cathode and hard carbon (HC) + stabilized lithium metal power (SLMP®) anode. Different cathode configurations, various SLMP loadings on HC anode, and two types of separators were investigated to achieve the optimal electrochemical performance of the LIC. Firstly, the cathode binders study suggests that the PTFE binder offers improved energy and power performances for LIC in comparison to PVDF. Secondly, the mass ratio of SLMP to HC is at 1:7 to obtain the optimized electrochemical performance for LIC among all the various studied mass ratios between lithium loading amounts and active anode material. Finally, compared to the separator Celgard PP 3501, cellulose based TF40-30 is proven to be a preferred separator for LIC.

  8. Electrochemical performance of mixed crystallographic phase nanotubes and nanosheets of titania and titania-carbon/silver composites for lithium-ion batteries

    International Nuclear Information System (INIS)

    Das, Shyamal K.; Bhattacharyya, Aninda J.

    2011-01-01

    Highlights: → Carbon wired TiO 2 nanotubes as anode for lithium ion batteries. → Mixed phase nanotubes show higher energy and power density than titania nanosheets. → Lithium storage and phase stabilization influenced by morphology of carbon coating. - Abstract: The role of homogeneity in ex situ grown conductive coatings and dimensionality in the lithium storage properties of TiO 2 is discussed here. TiO 2 nanotube and nanosheet comprising of mixed crystallographic phases of anatase and TiO 2 (B) have been synthesized by an optimized hydrothermal method. Surface modifications of TiO 2 nanotube are realized via coating the nanotube with Ag nanoparticles and amorphous carbon. The first discharge cycle capacity (at current rate = 10 mA g -1 ) for TiO 2 nanotube and nanosheet were 355 mAh g -1 and 225 mAh g -1 , respectively. The conductive surface coating stabilized the titania crystallographic structure during lithium insertion-deinsertion processes via reduction in the accessibility of lithium ions to the trapping sites. The irreversible capacity is beneficially minimized from 110 mAh g -1 for TiO 2 nanotubes to 96 mAh g -1 and 57 mAh g -1 respectively for Ag and carbon modified TiO 2 nanotubes. The homogeneously coated amorphous carbon over TiO 2 renders better lithium battery performance than randomly distributed Ag nanoparticles coated TiO 2 due to efficient hopping of electrons.

  9. Effect of the capacity design of activated carbon cathode on the electrochemical performance of lithium-ion capacitors

    International Nuclear Information System (INIS)

    Shi, Zhiqiang; Zhang, Jin; Wang, Jing; Shi, Jingli; Wang, Chengyang

    2015-01-01

    Highlights: • MCMB with the optimal pre-lithiation capacity as negative electrode in LIC. • The capacity design of cathode affects the electrochemical performance of LIC. • The optimal designed capacity of positive electrode has been proposed. - ABSTRACT: Lithium-ion capacitors (LICs) are assembled with activated carbon (AC) cathode and pre-lithiated mesocarbon microbeads (MCMB) anode. The effect of AC cathode capacity design on the electrochemical performance of LIC is investigated by the galvanostatic charging-discharging and electrochemical impedance tests. As the designed capacity of AC positive electrode is lower than 50 mAh g −1 , the working potential of negative electrode is always in the low and stable plateau, which is conductive to the sufficient utilization and the working potential stability of positive electrode. When the designed capacity of positive electrode is higher than 50 mAh g −1 , the instability of negative electrode directly causes the reduced utilization and shortened working potential range of the positive electrode, which is responsible for the capacity attenuation and cycle performance deterioration of LIC. The positive electrode capacity design can realize the optimization of electrochemical performance of LIC. LIC50 exhibits the optimal electrochemical performance, high energy density up to 92.3 Wh kg −1 and power density as high as 5.5 kW kg −1 (based on active material mass of two electrodes), excellent capacity retention of 97.0 % after 1000 cycles. The power density and cycle performance of LIC can be further improved by reducing the AC positive electrode designed capacity

  10. Preparation and electrochemical performance of sulfur-alumina cathode material for lithium-sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Kang [Faculty of Material Science and Chemistry, China University of Geosciences, 388 Lumo Road, 430074 Wuhan (China); Wang, Shengping, E-mail: spwang@cug.edu.cn [Faculty of Material Science and Chemistry, China University of Geosciences, 388 Lumo Road, 430074 Wuhan (China); Zhang, Hanyu; Wu, Jinping [Faculty of Material Science and Chemistry, China University of Geosciences, 388 Lumo Road, 430074 Wuhan (China)

    2013-06-01

    Highlights: ► Micron-sized alumina was synthesized as adsorbent for lithium-sulfur batteries. ► Sulfur-alumina material was synthesized via crystallizing nucleation. ► The Al{sub 2}O{sub 3} can provide surface area for the deposition of Li{sub 2}S and Li{sub 2}S{sub 2}. ► The discharge capacity of the battery is improved during the first several cycles. - Abstract: Nano-sized sulfur particles exhibiting good adhesion with conducting acetylene black and alumina composite materials were synthesized by means of an evaporated solvent and a concentrated crystallization method for use as the cathodes of lithium-sulfur batteries. The composites were characterized and examined by X-ray diffraction, environmental scanning electron microscopy and electrochemical methods, such as cyclic voltammetry, electrical impedance spectroscopy and charge–discharge tests. Micron-sized flaky alumina was employed as an adsorbent for the cathode material. The initial discharge capacity of the cathode with the added alumina was 1171 mAh g{sup −1}, and the remaining capacity was 585 mAh g{sup −1} after 50 cycles at 0.25 mA cm{sup −2}. Compared with bare sulfur electrodes, the electrodes containing alumina showed an obviously superior cycle performance, confirming that alumina can contribute to reducing the dissolution of polysulfides into electrolytes during the sulfur charge–discharge process.

  11. Lithium electrode and an electrical energy storage device containing the same

    Science.gov (United States)

    Lai, San-Cheng

    1976-07-13

    An improved lithium electrode structure comprises an alloy of lithium and silicon in specified proportions and a supporting current-collecting matrix in intimate contact with said alloy. The lithium electrode of the present invention is utilized as the negative electrode in a rechargeable electrochemical cell.

  12. Lithium-ion batteries advances and applications

    CERN Document Server

    Pistoia, Gianfranco

    2014-01-01

    Lithium-Ion Batteries features an in-depth description of different lithium-ion applications, including important features such as safety and reliability. This title acquaints readers with the numerous and often consumer-oriented applications of this widespread battery type. Lithium-Ion Batteries also explores the concepts of nanostructured materials, as well as the importance of battery management systems. This handbook is an invaluable resource for electrochemical engineers and battery and fuel cell experts everywhere, from research institutions and universities to a worldwi

  13. High electrochemical energy storage in self-assembled nest-like CoO nanofibers with long cycle life

    Energy Technology Data Exchange (ETDEWEB)

    Pramanik, Atin; Maiti, Sandipan [CSIR-Central Glass & Ceramic Research Institute, Fuel Cell & Battery Division (India); Sreemany, Monjoy [CSIR-Central Glass & Ceramic Research Institute, Advanced Mechanical and Materials Characterization Division (India); Mahanty, Sourindra, E-mail: mahanty@cgcri.res.in [CSIR-Central Glass & Ceramic Research Institute, Fuel Cell & Battery Division (India)

    2016-04-15

    Developing efficient electrode material is essential to keep pace with the demand for high energy density together with high power density and long cycle life in next generation energy storage devices. Herein, we report the electrochemical properties of hydrothermally synthesized CoO nanofibers of diameter 30–80 nm assembled in a nest-like morphology which showed a very high reversible lithium storage capacity of 2000 mA h g{sup −1} after 600 cycles at 0.1 mA cm{sup −2} as lithium-ion battery anode. Systematic investigation by ex situ transmission electron microscopy, X-ray photoelectron spectroscopy, cyclic voltammetry, and impedance spectroscopy at different cycling stages indicated that the extraordinary performance could be related to an enhancement in the Co{sup 2+}↔Co{sup x+} (2 < x ≤ 3) redox process in addition to the commonly believed structural and morphological evolution during cycling favoring generation of large number of accessible active sites for lithium insertion. Further, when examined as a supercapacitor electrode in 1.0 M KOH, a capacitance of 1167 F g{sup −1} is achieved from these 1D CoO nanofibers after 10,000 charge discharge cycles at a high current density of 5 A g{sup −1} demonstrating good application potential.Graphical AbstractNest-like CoO nanofibers showed a reversible lithium storage capacity of 2000 mA h g{sup −1} after 600 cycles as LIB anode and a capacitance of 1167 F g{sup −1} after 10,000 cycles as electrochemical supercapacitor.

  14. Novel Pyrrolinium-based Ionic Liquids for Lithium Ion Batteries: Effect of the Cation on Physicochemical and Electrochemical Properties

    International Nuclear Information System (INIS)

    Kim, Hyung-Tae; Kwon, Oh Min; Mun, Junyoung; Oh, Seung M.; Yim, Taeeun; Kim, Young Gyu

    2017-01-01

    Lithium ion batteries (LIBs) are one of the most promising energy conversion/storage systems, but the low thermal stability of the current electrolytes in LIBs should be improved to expand their potential applications. To enhance the safety properties of LIBs, novel pyrrolinium-based ionic liquids (ILs) were proposed as an alternative electrolyte to the current carbonate electrolyte, which have some task-specific functional groups, i.e., a planar C=N double bond, a C-O ether linkage, and no unstable C-H bond, designed to improve their electrochemical performances as well as the physicochemical properties. As a result, the pyrrolinium-based ILs exhibited much improved physicochemical and electrochemical properties compared to those of the known ILs. Among the prepared ILs, N-allyl-2-methoxypyrrolinium bis(fluorosulfonyl)imide (A(OMe)Pyrl-FSI, 4) showed the high ionic conductivity (10.2 mS cm −1 ), the very good cycling performance (99.3% of retention ratio after 50 cycles) with a LiFePO 4 electrode, and the much improved lithium ion transference number (0.19). IL 4 also had the remarkable rate capability at 5 C-rate with the retention ratio of 81.2% (124.8 mA h g −1 ), compared to the initial discharge capacity of 153.7 mA h g −1 at 0.1 C-rate. In addition, both their high thermal stability and non-flammability were also confirmed.

  15. Preparation and electrochemical performances of cubic shape Cu2O as anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Zhang, C.Q.; Tu, J.P.; Huang, X.H.; Yuan, Y.F.; Chen, X.T.; Mao, F.

    2007-01-01

    Cubic and star-shaped crystalline Cu 2 O particles were synthesized by reducing the copper citrate complex solution with glucose. The microstructure and morphology of the Cu 2 O were characterized by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical properties of the Cu 2 O as anode materials for lithium ion batteries were measured by galvanostatic charge-discharge tests. The as-synthesized Cu 2 O particles were 1-2 μm with narrow distribution and the shape of Cu 2 O particles had an effect on the electrochemical properties. The cubic Cu 2 O particles delivered a higher reversible discharge capacity (390 mAh g -1 ) than the star-shaped Cu 2 O, and also exhibited good cyclability. The star-shaped Cu 2 O particles presented poor cyclability due to pulverization and deterioration after cycling, but the morphology of the cubic Cu 2 O particles was stable even after 50 cycles

  16. Synthesis and electrochemical performance of surface-modified nano-sized core/shell tin particles for lithium ion batteries

    International Nuclear Information System (INIS)

    Schmuelling, Guido; Meyer, Hinrich-Wilhelm; Placke, Tobias; Winter, Martin; Oehl, Nikolas; Knipper, Martin; Kolny-Olesiak, Joanna; Plaggenborg, Thorsten; Parisi, Jürgen

    2014-01-01

    Tin is able to lithiate and delithiate reversibly with a high theoretical specific capacity, which makes it a promising candidate to supersede graphite as the state-of-the-art negative electrode material in lithium ion battery technology. Nevertheless, it still suffers from poor cycling stability and high irreversible capacities. In this contribution, we show the synthesis of three different nano-sized core/shell-type particles with crystalline tin cores and different amorphous surface shells consisting of SnO x and organic polymers. The spherical size and the surface shell can be tailored by adjusting the synthesis temperature and the polymer reagents in the synthesis, respectively. We determine the influence of the surface modifications with respect to the electrochemical performance and characterize the morphology, structure, and thermal properties of the nano-sized tin particles by means of high-resolution transmission electron microscopy, x-ray diffraction, and thermogravimetric analysis. The electrochemical performance is investigated by constant current charge/discharge cycling as well as cyclic voltammetry. (paper)

  17. The preparation and electrochemical performances of LiFePO4-multiwalled nanotubes composite cathode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Feng Yan

    2010-01-01

    LiFePO 4 -MWCNTs (multi-walled carbon nanotubes) composite cathode materials were prepared by mixing LiFePO 4 and MWCNTs in ethanol followed by heat-treatment at 500 deg. C for 5 h. The structural, morphology and electrochemical performances of LiFePO 4 -MWCNTs composite materials were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), galvanostatic charge-discharge cycle tests, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The results indicated that MWCNTs adding improved the electronic conductivity, the discharge capacity, cycle stability and lithium ion diffusion kinetics of LiFePO 4 , but MWCNTs adding did not charge the orthorhombic olivine-type structure of LiFePO 4 . In all these prepared LiFePO 4 with x wt.% MWCNTs (x = 4, 7, 10) composites, 7 wt.% MWCNTs adding composite cathode shows the best electrochemical performance, which gets an initial discharge capacity of 152.7 mAh g -1 at 0.18 C discharge rates with capacity retention ratio of 97.77% after 100 cycles.

  18. Different types of pre-lithiated hard carbon as negative electrode material for lithium-ion capacitors

    International Nuclear Information System (INIS)

    Zhang, Jin; Liu, Xifeng; Wang, Jing; Shi, Jingli; Shi, Zhiqiang

    2016-01-01

    Highlights: • Two types of HC materials with different properties as negative electrode. • Lithium ion intercalation plateau of HC affects electrochemical performance of LIC. • The electrochemical performance of LIC is operated at different potential ranges. • The selection of HC and appropriate potential range of LIC have been proposed. - ABSTRACT: Lithium-ion capacitors (LICs) are assembled with activated carbon (AC) cathode and pre-lithiated hard carbon (HC) anode. Two kinds of HC materials with different physical and electrochemical behaviors have been investigated as the negative electrodes for LIC. Compared with spherical HC, the irregular HC shows a distinct lithium ion intercalation plateau in the charge–discharge process. The existence of lithium ion intercalation plateau for irregular HC greatly affects the electrochemical behavior of HC negative electrode and AC positive electrode. The effect of working potential range on the electrochemical performance of LIC-SH and LIC-IH is investigated by the galvanostatic charging–discharging, electrochemical impedance tests and cycle performance testing. The charge–discharge potential range of the irregular HC negative electrode is lower than the spherical HC electrode due to the existence of lithium ion intercalation plateau, which is conducive to the sufficient utilization of the AC positive electrode. The working potential range of LIC should be controlled to realize the optimization of electrochemical performance of LIC. LIC-IH at the working potential range of 2.0-4.0 V exhibits the optimal electrochemical performance, high energy density up to 85.7 Wh kg −1 and power density as high as 7.6 kW kg −1 (based on active material mass of two electrodes), excellent capacity retention about 96.0% after 5000 cycles.

  19. Electrochemical lithium and sodium intercalation into the tantalum-rich layered chalcogenides Ta2Se and Ta2Te3

    International Nuclear Information System (INIS)

    Lavela, P.; Tirado, J.L.

    1999-01-01

    Two-layered tantalum chalcogenides are evaluated as alkali metal intercalation hosts in lithium and sodium electrochemical cells. The metal-rich pseudo-two-dimensional solid Ta 2 Se shows a poor intercalation behaviour. Lithium reacts with the selenide by deintercalating selenium from the blocks of Ta-related b.c.c. structure leading to a collapse of the structure and the formation of tantalum metal. Sodium is reversibly intercalated to a limited extent leading to complex structural changes in the selenide, as revealed by electron diffraction. The two-dimensional telluride Ta 2 Te 3 allows a topotactic intercalation of lithium below 1 F/mol, while a more extended reaction leads to sample amorphization. The better intercalation behaviour of this solid can be related with the one-atom thick metal layer and the van der Waals gap separating tellurium atoms of successive layers. Sodium can be reversibly intercalated into Ta 2 Te 3 in sodium cells which show a good cycling behaviour. Exposure of the intercalated solid to water vapour allows the preparation of hydrated products with a monolayer or a bilayer of water molecules solvating sodium in the interlayer space. (orig.)

  20. Structural and electrochemical properties of SnO nanoflowers as an anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Iqbal, M. Zubair; Wang, Fengping; Zhao, Hailei; Rafique, M. Yasir; Wang, Jie; Li, Quanshui

    2012-01-01

    Graphical abstract: -- Novel self-assembled highly hierarchical SnO nanoflowers with acute edge petals have been successfully synthesized by a template-free hydrothermal growth method using SnCl 2 ·2H 2 O and KOH as precursors. Field emission scanning electron microscopy results show that the flower-like SnO architectureis in the range 4–7 μm. Furthermore, Raman modes at A 1g = 212 and B 1g = 114 cm −1 further testify to the existence of nanotetragonal phase SnO. The electrochemical results suggest that synthesized SnO nanoflowers are a promising anode material for lithium ion batteries.

  1. Control oriented 1D electrochemical model of lithium ion battery

    International Nuclear Information System (INIS)

    Smith, Kandler A.; Rahn, Christopher D.; Wang, Chao-Yang

    2007-01-01

    Lithium ion (Li-ion) batteries provide high energy and power density energy storage for diverse applications ranging from cell phones to hybrid electric vehicles (HEVs). For efficient and reliable systems integration, low order dynamic battery models are needed. This paper introduces a general method to generate numerically a fully observable/controllable state variable model from electrochemical kinetic, species and charge partial differential equations that govern the discharge/charge behavior of a Li-ion battery. Validated against a 313th order nonlinear CFD model of a 6 Ah HEV cell, a 12th order state variable model predicts terminal voltage to within 1% for pulse and constant current profiles at rates up to 50 C. The state equation is constructed in modal form with constant negative real eigenvalues distributed in frequency space from 0 to 10 Hz. Open circuit potential, electrode surface concentration/reaction distribution coupling and electrolyte concentration/ionic conductivity nonlinearities are explicitly approximated in the model output equation on a local, electrode-averaged and distributed basis, respectively. The balanced realization controllability/observability gramian indicates that the fast electrode surface concentration dynamics are more observable/controllable than the electrode bulk concentration dynamics (i.e. state of charge)

  2. Electrochemical Properties of LLTO/Fluoropolymer-Shell Cellulose-Core Fibrous Membrane for Separator of High Performance Lithium-Ion Battery

    Science.gov (United States)

    Huang, Fenglin; Liu, Wenting; Li, Peiying; Ning, Jinxia; Wei, Qufu

    2016-01-01

    A superfine Li0.33La0.557TiO3 (LLTO, 69.4 nm) was successfully synthesized by a facile solvent-thermal method to enhance the electrochemical properties of the lithium-ion battery separator. Co-axial nanofiber of cellulose and Poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) was prepared by a co-axial electrospinning technique, in which the shell material was PVDF-HFP and the core was cellulose. LLTO superfine nanoparticles were incorporated into the shell of the PVDF-HFP. The core–shell composite nanofibrous membrane showed good wettability (16.5°, contact angle), high porosity (69.77%), and super electrolyte compatibility (497%, electrolyte uptake). It had a higher ionic conductivity (13.897 mS·cm−1) than those of pure polymer fibrous membrane and commercial separator. In addition, the rate capability (155.56 mAh·g−1) was also superior to the compared separator. These excellent performances endowed LLTO composite nanofibrous membrane as a promising separator for high-performance lithium-ion batteries. PMID:28787873

  3. Cu2Sb thin film electrodes prepared by pulsed laser deposition f or lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Song, Seung-Wan; Reade, Ronald P.; Cairns, Elton J.; Vaughey, Jack T.; Thackeray, Michael M.; Striebel, Kathryn A.

    2003-08-01

    Thin films of Cu2Sb, prepared on stainless steel and copper substrates with a pulsed laser deposition technique at room temperature, have been evaluated as electrodes in lithium cells. The electrodes operate by a lithium insertion/copper extrusion reaction mechanism, the reversibility of which is superior when copper substrates are used, particularly when electrochemical cycling is restricted to the voltage range 0.65-1.4 V vs. Li/Li+. The superior performance of Cu2Sb films on copper is attributed to the more active participation of the extruded copper in the functioning of the electrode. The continual and extensive extrusion of copper on cycling the cells leads to the isolation of Li3Sb particles and a consequent formation of Sb. Improved cycling stability of both types of electrodes was obtained when cells were cycled between 0.65 and 1.4 V. A low-capacity lithium-ion cell with Cu2Sb and LiNi0.8Co0.15Al0.05O2 electrodes, laminated from powders, shows excellent cycling stability over the voltage range 3.15 - 2.2 V, the potential difference corresponding to approximately 0.65-1.4 V for the Cu2Sb electrode vs. Li/Li+. Chemical self-discharge of lithiated Cu2Sb electrodes by reaction with the electrolyte was severe when cells were allowed to relax on open circuit after reaching a lower voltage limit of 0.1 V. The solid electrolyte interphase (SEI) layer formed on Cu2Sb electrodes after cells had been cycled between 1.4 and 0.65 V vs. Li/Li+ was characterized by Fourier-transform infrared spectroscopy; the SEI layer contributes to the large irreversible capacity loss on the initial cycle of these cells. The data contribute to a better understanding of the electrochemical behavior of intermetallic electrodes in rechargeable lithium batteries.

  4. The electrochemical generation of useful chemical species from lunar materials

    Science.gov (United States)

    Tsai, Kan J.; Kuchynka, Daniel J.; Sammells, Anthony F.

    1989-01-01

    The current status of work on an electrochemical technology for the simultaneous generation of oxygen and lithium from a Li2O containing molten salt (Li2O-LiCl-LiF) is discussed. The electrochemical cell utilizes an oxygen vacancy conducting solid electrolyte, yttria-stabilized zirconia, to effect separation between the oxygen evolving and lithium reduction half-cell reactions. The cell, which operates at 700 to 800 C, possesses rapid electrode kinetics at the lithium-alloy electrode with exchange current density values being greater than 60 mA/sq cm, showing high reversibility for this reaction. When used in the electrolytic mode, lithium produced at the negative electrode would be continuously removed from the cell for later use (under lunar conditions) as an easily storable reducting agent (compared to H2) for the chemical refining of lunar ores via the general reaction: 2Li + MO yields Li2O + M where MO represents a lunar ore. Emphasis to this time has been on the simulated lunar ore ilmenite (FeTiO3), which we have found becomes chemically reduced by Li at 432 C. Furthermore, both Fe2O3 and TiO2 have been reduced by Li to give the corresponding metal. This electrochemical approach provides a convenient route for producing metals under lunar conditions and oxygen for the continuous maintenance of human habitats on the Moon's surface. Because of the high reversibility of this electrochemical system, it has also formed the basis for the lithium-oxygen secondary battery. This secondary lithium-oxygen battery system posses the highest theoretical energy density yet investigated.

  5. A novel method for identification of lithium-ion battery equivalent circuit model parameters considering electrochemical properties

    Science.gov (United States)

    Zhang, Xi; Lu, Jinling; Yuan, Shifei; Yang, Jun; Zhou, Xuan

    2017-03-01

    This paper proposes a novel parameter identification method for the lithium-ion (Li-ion) battery equivalent circuit model (ECM) considering the electrochemical properties. An improved pseudo two-dimension (P2D) model is established on basis of partial differential equations (PDEs), since the electrolyte potential is simplified from the nonlinear to linear expression while terminal voltage can be divided into the electrolyte potential, open circuit voltage (OCV), overpotential of electrodes, internal resistance drop, and so on. The model order reduction process is implemented by the simplification of the PDEs using the Laplace transform, inverse Laplace transform, Pade approximation, etc. A unified second order transfer function between cell voltage and current is obtained for the comparability with that of ECM. The final objective is to obtain the relationship between the ECM resistances/capacitances and electrochemical parameters such that in various conditions, ECM precision could be improved regarding integration of battery interior properties for further applications, e.g., SOC estimation. Finally simulation and experimental results prove the correctness and validity of the proposed methodology.

  6. Electrochemical behavior of sebaconitrile as a cosolvent in the formulation of electrolytes at high potentials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Nanini-Maury, Elise; Światowska, Jolanta; Chagnes, Alexandre; Zanna, Sandrine; Tran-Van, Pierre; Marcus, Philippe; Cassir, Michel

    2014-01-01

    The electrochemical behavior of new high potential electrolyte containing sebaconitrile in LiPF 6 /EC:DMC or LiBF 4 was studied on glassy carbon and LiCoO 2 , LiCoPO 4 as positive electrode materials. The increase of sebaconitrile concentration in EC:DMC electrolyte provides better electrolyte stability at higher potentials on glassy carbon as observed by cyclic voltammetry. Promising electrochemical results showing good reversibility and insertion/deinsertion efficiency have been also obtained on LiCoPO 4 electrode cycled up to 5.3 V vs Li + /Li as upper potential limit. However, the cycling of LiCoPO 4 at higher potential (6 V vs Li + /Li) shows lower reversibility and efficiency of insertion/deinsertion process due to the oxidative decomposition of the electrolyte at high potentials. The surface analysis performed by X-ray photoelectron spectroscopy confirms the formation of a surface layer induced by electrolyte degradation on both types of positive electrodes, which hinder the Li diffusion. The layer composition and morphology vary as a function of electrolyte composition and type of electrode

  7. Mathematical modeling of the electrochemical impedance spectroscopy in lithium ion battery cycling

    International Nuclear Information System (INIS)

    Xie, Yuanyuan; Li, Jianyang; Yuan, Chris

    2014-01-01

    Electrochemical impedance spectroscopy (EIS) has been widely utilized as an experimental method for understanding the internal mechanisms and aging effect of lithium ion battery. However, the impedance interpretation still has a lot of difficulties. In this study, a multi-physics based EIS simulation approach is developed to study the cycling effect on the battery impedance responses. The SEI film growth during cycling is coherently coupled with the complicated charge, mass and energy transport processes. The EIS simulation is carried out by applying a perturbation voltage on the electrode surface, and the numerical results on cycled cells are compared with the corresponding experimental data. The effect of electrical double layer, electrode open circuit potential as well as the diffusivity of binary electrolyte are simulated on battery impedance responses. The influence of different SEI growth rate, thermal conditions and charging-discharging rate during cycling are also studied. This developed method can be potentially utilized for interpretation and analysis of experimental EIS results

  8. Electrochemical cell

    Science.gov (United States)

    Kaun, T.D.

    An improved secondary electrochemical cell is disclosed having a negative electrode of lithium aluminum, a positive electrode of iron sulfide, a molten electrolyte of lithium chloride and potassium chloride, and the combination that the fully charged theoretical capacity of the negative electrode is in the range of 0.5 to 1.0 that of the positive electrode. The cell thus is negative electrode limiting during discharge cycling. Preferably, the negative electrode contains therein, in the approximate range of 1 to 10 volume % of the electrode, an additive from the materials of graphitized carbon, aluminum-iron alloy, and/or magnesium oxide.

  9. Enhanced electrochemical properties of F-doped Li2MnSiO4/C for lithium ion batteries

    Science.gov (United States)

    Wang, Chao; Xu, Youlong; Sun, Xiaofei; Zhang, Baofeng; Chen, Yanjun; He, Shengnan

    2018-02-01

    The Li2MnSiO4 as a novel cathode material for lithium ion batteries, performs high specific capacity, high thermal stability, low cost and etc. However, it suffers from relatively low electronic conductivity and lithium ion diffusion rate. Herein, we successfully introduce fluorine to Li2MnSiO4 (Li2MnSiO4-xFx, x = 0.00, 0.01, 0.03 and 0.05) to overcome these obstacles. The results show that F doping not only enlarges the lattice parameters but also decreases the particle size, synergistically improving the lithium ion diffusion of Li2MnSiO4. Moreover, F doping increase electronic conductivity of Li2MnSiO4/C by inhibiting the formation of C-O bonds in the carbon layers. Meanwhile, F doping improves the crystallinity and stabilizes the crystal structure of Li2MnSiO4. Finally, the Li2MnSiO3.97F0.03/C with the best electrochemical performances delivers the initial specific discharge capacity of 279 mA h g-1 at 25mA g-1 current density from 1.5 V to 4.8 V. Also, it maintains a higher capacity (201 mA h g-1) than F-free Li2MnSiO4 (145 mA h g-1) after 50 cycles.

  10. Graphene-supported SnO2 nanoparticles prepared by a solvothermal approach for an enhanced electrochemical performance in lithium-ion batteries

    OpenAIRE

    Wang, Bei; Su, Dawei; Park, Jinsoo; Ahn, Hyojun; Wang, Guoxiu

    2012-01-01

    SnO2 nanoparticles were dispersed on graphene nanosheets through a solvothermal approach using ethylene glycol as the solvent. The uniform distribution of SnO2 nanoparticles on graphene nanosheets has been confirmed by scanning electron microscopy and transmission electron microscopy. The particle size of SnO2 was determined to be around 5 nm. The as-synthesized SnO2/graphene nanocomposite exhibited an enhanced electrochemical performance in lithium-ion batteries, compared with bare graphene ...

  11. Scalable integration of Li5FeO4 towards robust, high-performance lithium-ion hybrid capacitors.

    Science.gov (United States)

    Park, Min-Sik; Lim, Young-Geun; Hwang, Soo Min; Kim, Jung Ho; Kim, Jeom-Soo; Dou, Shi Xue; Cho, Jaephil; Kim, Young-Jun

    2014-11-01

    Lithium-ion hybrid capacitors have attracted great interest due to their high specific energy relative to conventional electrical double-layer capacitors. Nevertheless, the safety issue still remains a drawback for lithium-ion capacitors in practical operational environments because of the use of metallic lithium. Herein, single-phase Li5FeO4 with an antifluorite structure that acts as an alternative lithium source (instead of metallic lithium) is employed and its potential use for lithium-ion capacitors is verified. Abundant Li(+) amounts can be extracted from Li5FeO4 incorporated in the positive electrode and efficiently doped into the negative electrode during the first electrochemical charging. After the first Li(+) extraction, Li(+) does not return to the Li5FeO4 host structure and is steadily involved in the electrochemical reactions of the negative electrode during subsequent cycling. Various electrochemical and structural analyses support its superior characteristics for use as a promising lithium source. This versatile approach can yield a sufficient Li(+)-doping efficiency of >90% and improved safety as a result of the removal of metallic lithium from the cell. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Electrochemical-thermal modeling and microscale phase change for passive internal thermal management of lithium ion batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Fuller, Thomas F. (Georgia Institute of Technology, Atlanta, GA); Bandhauer, Todd (Georgia Institute of Technology, Atlanta, GA); Garimella, Srinivas (Georgia Institute of Technology, Atlanta, GA)

    2012-01-01

    A fully coupled electrochemical and thermal model for lithium-ion batteries is developed to investigate the impact of different thermal management strategies on battery performance. In contrast to previous modeling efforts focused either exclusively on particle electrochemistry on the one hand or overall vehicle simulations on the other, the present work predicts local electrochemical reaction rates using temperature-dependent data on commercially available batteries designed for high rates (C/LiFePO{sub 4}) in a computationally efficient manner. Simulation results show that conventional external cooling systems for these batteries, which have a low composite thermal conductivity ({approx}1 W/m-K), cause either large temperature rises or internal temperature gradients. Thus, a novel, passive internal cooling system that uses heat removal through liquid-vapor phase change is developed. Although there have been prior investigations of phase change at the microscales, fluid flow at the conditions expected here is not well understood. A first-principles based cooling system performance model is developed and validated experimentally, and is integrated into the coupled electrochemical-thermal model for assessment of performance improvement relative to conventional thermal management strategies. The proposed cooling system passively removes heat almost isothermally with negligible thermal resistances between the heat source and cooling fluid. Thus, the minimization of peak temperatures and gradients within batteries allow increased power and energy densities unencumbered by thermal limitations.

  13. Electrophoretic Nanocrystalline Graphene Film Electrode for Lithium Ion Battery

    International Nuclear Information System (INIS)

    Kaprans, Kaspars; Bajars, Gunars; Kucinskis, Gints; Dorondo, Anna; Mateuss, Janis; Gabrusenoks, Jevgenijs; Kleperis, Janis; Lusis, Andrejs

    2015-01-01

    Graphene sheets were fabricated by electrophoretic deposition method from water suspension of graphene oxide followed by thermal reduction. The formation of nanocrystalline graphene sheets has been confirmed by scanning electron microscopy, X-ray diffraction and Raman spectroscopy. The electrochemical performance of graphene sheets as anode material for lithium ion batteries was evaluated by cycling voltammetry, galvanostatic charge-discharge cycling, and electrochemical impedance spectroscopy. Fabricated graphene sheets exhibited high discharge capacity of about 1120 mAh·g −1 and demonstrated good reversibility of lithium intercalation and deintercalation in graphene sheet film with capacity retention over 85 % after 50 cycles. Results show that nanocrystalline graphene sheets prepared by EPD demonstrated a high potential for application as anode material in lithium ion batteries

  14. Ternary CNTs@TiO₂/CoO Nanotube Composites: Improved Anode Materials for High Performance Lithium Ion Batteries.

    Science.gov (United States)

    Madian, Mahmoud; Ummethala, Raghunandan; Naga, Ahmed Osama Abo El; Ismail, Nahla; Rümmeli, Mark Hermann; Eychmüller, Alexander; Giebeler, Lars

    2017-06-20

    TiO₂ nanotubes (NTs) synthesized by electrochemical anodization are discussed as very promising anodes for lithium ion batteries, owing to their high structural stability, high surface area, safety, and low production cost. However, their poor electronic conductivity and low Li⁺ ion diffusivity are the main drawbacks that prevent them from achieving high electrochemical performance. Herein, we report the fabrication of a novel ternary carbon nanotubes (CNTs)@TiO₂/CoO nanotubes composite by a two-step synthesis method. The preparation includes an initial anodic fabrication of well-ordered TiO₂/CoO NTs from a Ti-Co alloy, followed by growing of CNTs horizontally on the top of the oxide films using a simple spray pyrolysis technique. The unique 1D structure of such a hybrid nanostructure with the inclusion of CNTs demonstrates significantly enhanced areal capacity and rate performances compared to pure TiO₂ and TiO₂/CoO NTs, without CNTs tested under identical conditions. The findings reveal that CNTs provide a highly conductive network that improves Li⁺ ion diffusivity, promoting a strongly favored lithium insertion into the TiO₂/CoO NT framework, and hence resulting in high capacity and an extremely reproducible high rate capability.

  15. First principles simulation of the electrochemical behaviour of lithium battery materials; Modelisation du comportement electrochimique de materiaux pour batteries au lithium a partir de calculs de premiers principes

    Energy Technology Data Exchange (ETDEWEB)

    Rocquefelte, X.

    2001-10-01

    The functioning of a positive electrode in a lithium battery is based on the reversible intercalation of lithium. In some cases, such a reaction can lead to important structural modifications and therefore to an amorphization of the material. A theoretical approach is presented here that leads to structural predictions and simulations of electrochemical behaviour of positive electrode materials. In the first part, DFT (Density Functional Theory) formalisms and the respective advantages of FLAPW (Full potential Linearized Augmented Plane Waves) and PP/PW (Pseudopotential / Plane Waves) methods are discussed. In the second part are given some fundamental electrochemistry considerations related to the intercalation process, thermodynamics aspects and relationships with electronic structure. Then, an approach combining experimental data and geometry optimisation of structural hypotheses is given. This approach was first applied to a model compound LiMoS{sub 2}, and has been then generalised to systems of industrial interest such as Li{sub x}V{sub 2}O{sub 5} (0 {<=} x {<=} 3). The simulated X-ray diagrams of the optimised structures for LiMoS{sub 2} and {omega} - Li{sub 3}V{sub 2}O{sub 5} are in good agreement with experimental data. In the case of Li{sub x}V{sub 2}O{sub 5}, the first discharge curves starting from {alpha} - V{sub 2}O{sub 5} and {gamma}' - V{sub 2}O{sub 5} were then successfully simulated. A chemical bond analysis was carried out to help understand the origin of the distortion in LiMoS{sub 2} and the voltage variations in the electrochemical curves of Li{sub x}V{sub 2}O{sub 5}. This study clearly demonstrates that an approach combining first-principle calculations and available experimental data is invaluable in the structure determination of poorly crystallized compounds. Such a procedure contributes to the understanding of the phase transitions induced by the lithium intercalation in vanadium oxide compounds and can really be used in the research

  16. First principles simulation of the electrochemical behaviour of lithium battery materials; Modelisation du comportement electrochimique de materiaux pour batteries au lithium a partir de calculs de premiers principes

    Energy Technology Data Exchange (ETDEWEB)

    Rocquefelte, X

    2001-10-01

    The functioning of a positive electrode in a lithium battery is based on the reversible intercalation of lithium. In some cases, such a reaction can lead to important structural modifications and therefore to an amorphization of the material. A theoretical approach is presented here that leads to structural predictions and simulations of electrochemical behaviour of positive electrode materials. In the first part, DFT (Density Functional Theory) formalisms and the respective advantages of FLAPW (Full potential Linearized Augmented Plane Waves) and PP/PW (Pseudopotential / Plane Waves) methods are discussed. In the second part are given some fundamental electrochemistry considerations related to the intercalation process, thermodynamics aspects and relationships with electronic structure. Then, an approach combining experimental data and geometry optimisation of structural hypotheses is given. This approach was first applied to a model compound LiMoS{sub 2}, and has been then generalised to systems of industrial interest such as Li{sub x}V{sub 2}O{sub 5} (0 {<=} x {<=} 3). The simulated X-ray diagrams of the optimised structures for LiMoS{sub 2} and {omega} - Li{sub 3}V{sub 2}O{sub 5} are in good agreement with experimental data. In the case of Li{sub x}V{sub 2}O{sub 5}, the first discharge curves starting from {alpha} - V{sub 2}O{sub 5} and {gamma}' - V{sub 2}O{sub 5} were then successfully simulated. A chemical bond analysis was carried out to help understand the origin of the distortion in LiMoS{sub 2} and the voltage variations in the electrochemical curves of Li{sub x}V{sub 2}O{sub 5}. This study clearly demonstrates that an approach combining first-principle calculations and available experimental data is invaluable in the structure determination of poorly crystallized compounds. Such a procedure contributes to the understanding of the phase transitions induced by the lithium intercalation in vanadium oxide compounds and can really be used in the research of

  17. Effect of the synthesis method on the microstructure, morphology and electrochemical characteristics of α-Fe2O3 anodes for Lithium ion batteries

    International Nuclear Information System (INIS)

    Uzunov, I.; Klissurski, D.; Uzunova, S.; Aleksandrova, A.

    2009-01-01

    Effect of the synthesis method and temperature on some structural characteristics and electrochemical behaviour was investigated for samples of α-Fe 2 O 3 prepared from different precursors. The phase composition, morphology and crystallinity of the obtained materials were determined by X-ray diffraction analysis (XRD) and scanning electron microscopy (SEM). The electrochemical behaviour of the synthesized samples was studied within voltage range 0.01-2.5V and various current densities. The electrochemical behaviour of the obtained active anode materials was found to depend mostly on the ratio between mean particle size (MPS) and mean coherent domain size (MCDS). It was found that the ratio depends on the synthesis method and calcination temperature. By optimization of the synthesis processes α-Fe 2 O 3 was prepared with optimal microstructure and particle size, a promising anode material for lithium ion batteries. (authors)

  18. The Surface Coating of Commercial LiFePO4 by Utilizing ZIF-8 for High Electrochemical Performance Lithium Ion Battery

    Science.gov (United States)

    Xu, XiaoLong; Qi, CongYu; Hao, ZhenDong; Wang, Hao; Jiu, JinTing; Liu, JingBing; Yan, Hui; Suganuma, Katsuaki

    2018-03-01

    The requirement of energy-storage equipment needs to develop the lithium ion battery (LIB) with high electrochemical performance. The surface modification of commercial LiFePO4 (LFP) by utilizing zeolitic imidazolate frameworks-8 (ZIF-8) offers new possibilities for commercial LFP with high electrochemical performances. In this work, the carbonized ZIF-8 (CZIF-8) was coated on the surface of LFP particles by the in situ growth and carbonization of ZIF-8. Transmission electron microscopy indicates that there is an approximate 10 nm coating layer with metal zinc and graphite-like carbon on the surface of LFP/CZIF-8 sample. The N2 adsorption and desorption isotherm suggests that the coating layer has uniform and simple connecting mesopores. As cathode material, LFP/CZIF-8 cathode-active material delivers a discharge specific capacity of 159.3 mAh g-1 at 0.1C and a discharge specific energy of 141.7 mWh g-1 after 200 cycles at 5.0C (the retention rate is approximate 99%). These results are attributed to the synergy improvement of the conductivity, the lithium ion diffusion coefficient, and the degree of freedom for volume change of LFP/CZIF-8 cathode. This work will contribute to the improvement of the cathode materials of commercial LIB.[Figure not available: see fulltext.

  19. Synthesis and characterization of high performance electrode materials for lithium ion batteries

    Science.gov (United States)

    Hong, Jian

    Lithium-ion batteries have revolutionized portable electronics. Electrode reactions in these electrochemical systems are based on reversible intercalation of Li+ ions into the host electrode material with a concomitant addition/removal of electrons into the host. If such batteries are to find a wider market such as the automotive industry, less expensive and higher capacity electrode materials will be required. The olivine phase lithium iron phosphate has attracted the most attention because of its low cost and safety (high thermal and chemical stability). However, it is an intriguing fundamental problem to understand the fast electrochemical response from the poorly electronic conducting two-phase LiFePO4/FePO 4 system. This thesis focuses on determining the rate-limit step of LiFePO4. First, a LiFePO4 material, with vanadium substituting on the P-site, was synthesized, and found that the crystal structure change may cause high lithium diffusivity. Since an accurate Li diffusion coefficient cannot be measured by traditional electrochemical method in a three-electrode cell due to the phase transformation during measurement, a new method to measure the intrinsic electronic and ionic conductivity of mixed conductive LiFePO 4 was developed. This was based on the conductivity measurements of mixed conductive solid electrolyte using electrochemical impedance spectroscopy (EIS) and blocking electrode. The effects of ionic/electronic conductivity and phase transformation on the rate performance of LiFePO4 were also first investigated by EIS and other electrochemical technologies. Based on the above fundamental kinetics studies, an optimized LiFePO4 was used as a target to deposit 1mum LiFePO4 thin film at Oak Ridge National Laboratory using radio frequency (RF) magnetron sputtering. Similar to the carbon coated LiFePO4 powder electrode, the carbon-contained RF LiFePO4 film with no preferential orientation showed excellent capacity and rate capability both at 25°C and -20

  20. Synthesis and Electrochemical Performance of a Lithium Titanium Phosphate Anode for Aqueous Lithium-Ion Batteries

    KAUST Repository

    Wessells, Colin; La Mantia, Fabio; Deshazer, Heather; Huggins, Robert A.; Cui, Yi

    2011-01-01

    Lithium-ion batteries that use aqueous electrolytes offer safety and cost advantages when compared to today's commercial cells that use organic electrolytes. The equilibrium reaction potential of lithium titanium phosphate is -0.5 V with respect

  1. Lithium-Ion Electrolytes Containing Flame Retardant Additives for Increased Safety Characteristics

    Science.gov (United States)

    Smart, Marshall C. (Inventor); Smith, Kiah A. (Inventor); Bugga, Ratnakumar V. (Inventor); Prakash, Surya G. (Inventor); Krause, Frederick Charles (Inventor)

    2014-01-01

    The invention discloses various embodiments of Li-ion electrolytes containing flame retardant additives that have delivered good performance over a wide temperature range, good cycle life characteristics, and improved safety characteristics, namely, reduced flammability. In one embodiment of the invention there is provided an electrolyte for use in a lithium-ion electrochemical cell, the electrolyte comprising a mixture of an ethylene carbonate (EC), an ethyl methyl carbonate (EMC), a fluorinated co-solvent, a flame retardant additive, and a lithium salt. In another embodiment of the invention there is provided an electrolyte for use in a lithium-ion electrochemical cell, the electrolyte comprising a mixture of an ethylene carbonate (EC), an ethyl methyl carbonate (EMC), a flame retardant additive, a solid electrolyte interface (SEI) film forming agent, and a lithium salt.

  2. Preparation of octahedral CuO micro/nanocrystals and electrochemical performance as anode for lithium-ion battery

    International Nuclear Information System (INIS)

    Feng, Lili; Xuan, Zhewen; Bai, Yang; Zhao, Hongbo; Li, Li; Chen, Yashun; Yang, Xianqin; Su, Changwei; Guo, Junming; Chen, Xiaokai

    2014-01-01

    Highlights: • Octahedral cupric oxides with hollow structure were prepared. • No hard template was used in the preparation of hollow cupric oxides. • The cupric oxides show good reversible capacity. - Abstract: Herein we report that three octahedral CuO samples with hollow or solid structure are successfully prepared by firstly preparation of Cu 2 O products using a chemical reduction method, then by calcination in a muffle furnace at 300 °C for 3 h in air atmosphere. The obtained CuO samples serve as a good model system for the study as anodes for lithium ion batteries. All the three CuO samples have high discharge specific capacity and good cycling stability from the 2nd cycling to the 50th cycling. Octahedral CuO hollow crystals with 400 nm in size have the highest reversible capacity and the smallest resistance. So their electrochemical performances are partly related to their morphologies. The results suggest that the as-prepared CuO samples, especially the 400 nm hollow octahedral CuO crystals could be a promising material for the anode of lithium-ion battery

  3. Preparation and electrochemical properties of nanocable-like Nb2O5/surface-modified carbon nanotubes composites for anode materials in lithium ion batteries

    International Nuclear Information System (INIS)

    Shi, Chongfu; Xiang, Kaixiong; Zhu, Yirong; Chen, Xianhong; Zhou, Wei; Chen, Han

    2017-01-01

    Highlights: •The acid pretreatment for CNTs is a key factor to fabricate nanocable-like Nb 2 O 5 /SMCNTs composites. •The polar functional groups can induce the symmetrical growth of Nb 2 O 5 nanoparticitles on the surface of SMCNTs. •SMCNTs can provide sufficient conductive contacts for composites and abundant active sites for electrochemical reaction. -- Abstract: Uniform nanocable-like Nb 2 O 5 /surface-modified carbon nanotubes (SMCNTs) composites for anode materials in lithium ion batteries were synthesized by hydrothermal method. It was indicated that Nb 2 O 5 nanoparticles were tightly and uniformly cultivated on carbon nanotubes when CNTs were pretreated with concentrated H 2 SO 4 . As a result, Nb 2 O 5 /SMCNTs composite materials showed remarkable electrochemical performance as anode materials for lithium-ion batteries. It delivered a high reversible capacity of 441 mA h g −1 cycled at the current density of 40 mA g −1 after 100 cycles and an excellent rate capacity of 185 mA h g −1 at the high current density of 5000 mA g −1 after 200 cycles.

  4. Inorganic Glue Enabling High Performance of Silicon Particles as Lithium Ion Battery Anode

    KAUST Repository

    Cui, Li-Feng

    2011-01-01

    Silicon, as an alloy-type anode material, has recently attracted lots of attention because of its highest known Li+ storage capacity (4200 mAh/g). But lithium insertion into and extraction from silicon are accompanied by a huge volume change, up to 300, which induces a strong strain on silicon and causes pulverization and rapid capacity fading due to the loss of the electrical contact between part of silicon and current collector. Silicon nanostructures such as nanowires and nanotubes can overcome the pulverization problem, however these nano-engineered silicon anodes usually involve very expensive processes and have difficulty being applied in commercial lithium ion batteries. In this study, we report a novel method using amorphous silicon as inorganic glue replacing conventional polymer binder. This inorganic glue method can solve the loss of contact issue in conventional silicon particle anode and enables successful cycling of various sizes of silicon particles, both nano-particles and micron particles. With a limited capacity of 800 mAh/g, relatively large silicon micron-particles can be stably cycled over 200 cycles. The very cheap production of these silicon particle anodes makes our method promising and competitive in lithium ion battery industry. © 2011 The Electrochemical Society.

  5. A series of spinel phase cathode materials prepared by a simple hydrothermal process for rechargeable lithium batteries

    International Nuclear Information System (INIS)

    Liang Yanyu; Bao Shujuan; Li Hulin

    2006-01-01

    A series of spinel-structured materials have been prepared by a simple hydrothermal procedure in an aqueous medium. The new synthetic method is time and energy saving i.e., no further thermal treatment and extended grinding. The main experimental process involved the insertion of lithium into electrolytic manganese dioxide with glucose as a mild reductant in an autoclave. Both the hydrothermal temperature and the presence of glucose play the critical roles in determining the final spinel integrity. Particular electrochemical performance has also been systematically explored, and the results show that Al 3+ , F - co-substituted spinels have the best combination of initial capacity and capacity retention among all these samples, exhibited the initial capacity of 115 mAh/g and maintained more than 90% of the initial value at the 50th cycle. - Graphical abstract: It is a SEM image of the spinel LiMn 2 O 4 , which was prepared by this novel hydrothermal procedure. It illustrates that reasonable-crystallized spinel oxide has occurred through the special hydrothermal process and the average particle size declined to about 1 μm. This homogeneous grain size distribution provides an important morphological basis for the reversibility and accessibility of lithium ion insertion/extraction reactions

  6. Nanoscale Protection Layers To Mitigate Degradation in High-Energy Electrochemical Energy Storage Systems.

    Science.gov (United States)

    Lin, Chuan-Fu; Qi, Yue; Gregorczyk, Keith; Lee, Sang Bok; Rubloff, Gary W

    2018-01-16

    In the pursuit of energy storage devices with higher energy and power, new ion storage materials and high-voltage battery chemistries are of paramount importance. However, they invite-and often enhance-degradation mechanisms, which are reflected in capacity loss with charge/discharge cycling and sometimes in safety problems. Degradation mechanisms are often driven by fundamentals such as chemical and electrochemical reactions at electrode-electrolyte interfaces, volume expansion and stress associated with ion insertion and extraction, and profound inhomogeneity of electrochemical behavior. While it is important to identify and understand these mechanisms at some reasonable level, it is even more critical to design strategies to mitigate these degradation pathways and to develop means to implement and validate the strategies. A growing set of research highlights the mitigation benefits achievable by forming thin protection layers (PLs) intentionally created as artificial interphase regions at the electrode-electrolyte interface. These advances illustrate a promising-perhaps even generic-pathway for enabling higher-energy and higher-voltage battery configurations. In this Account, we summarize examples of such PLs that serve as mitigation strategies to avoid degradation in lithium metal anodes, conversion-type electrode materials, and alloy-type electrodes. Examples are chosen from a larger body of electrochemical degradation research carried out in Nanostructures for Electrical Energy Storage (NEES), our DOE Energy Frontier Research Center. Overall, we argue on the basis of experimental and theoretical evidence that PLs effectively stabilize the electrochemical interfaces to prevent parasitic chemical and electrochemical reactions and mitigate the structural, mechanical, and compositional degradation of the electrode materials at the electrode-electrolyte interfaces. The evidenced improvement in performance metrics is accomplished by (1) establishing a homogeneous

  7. Electrochemical improvement of low-temperature petroleum cokes by chemical oxidation with H2O2 for their use as anodes in lithium ion batteries

    International Nuclear Information System (INIS)

    Concheso, A.; Santamaria, R.; Menendez, R.; Jimenez-Mateos, J.M.; Alcantara, R.; Lavela, P.; Tirado, J.L.

    2006-01-01

    The electrochemical performance of non-graphitized petroleum cokes has been improved by mild oxidation using hydrogen peroxide, a procedure used for the first time in these materials. For this purpose, various carbonisation temperatures and H 2 O 2 treatments were tested. For low sulfur content cokes, the aqueous oxidative treatment significantly increases the capacity values above 372 mAh/g during the first cycles. In contrast, cokes with a sulfur content of ca. 5%, did not shown a real improvement. The former results have been interpreted in terms of an effective oxidation of the particles surface, which removes unorganized carbon, where lithium can be irreversibly trapped. Moreover, a stable and less resistive passivating layer grows during the first discharge of lithium, as revealed by impedance spectroscopy. Therefore, chemical procedures, as mild oxidation, open an interesting field of research for the improvement of disordered carbons as anode materials in lithium ion batteries

  8. Effect of calcination temperature on microstructure and electrochemical performance of lithium-rich layered oxide cathode materials

    International Nuclear Information System (INIS)

    Ma, Quanxin; Peng, Fangwei; Li, Ruhong; Yin, Shibo; Dai, Changsong

    2016-01-01

    Highlights: • A series of Li-rich layered oxide cathode materials (Li_1_._2Mn_0_._5_6Ni_0_._1_6Co_0_._0_8O_2) were successfully synthesized via a two-step synthesis method. • The effects of calcination temperature on the cathode materials were researched in detail. • A well-crystallized layered structure was obtained as the calcination temperature increased. • The samples calcined in a range of 850–900 °C exhibited excellent electrochemical performance. - Abstract: Lithium-rich layered oxide cathode materials (Li_1_._2Mn_0_._5_6Ni_0_._1_6Co_0_._0_8O_2 (LLMO)) were synthesized via a two-step synthesis method involving co-precipitation and high-temperature calcination. The effects of calcination temperature on the cathode materials were studied in detail. Structural and morphological characterizations revealed that a well-crystallized layered structure was obtained at a higher calcination temperature. Electrochemical performance evaluation revealed that a cathode material obtained at a calcination temperature of 850 °C delivered a high initial discharge capacity of 266.8 mAh g"−"1 at a 0.1 C rate and a capacity retention rate of 95.8% after 100 cycles as well as excellent rate capability. Another sample calcinated at 900 °C exhibited good cycling stability. It is concluded that the structural stability and electrochemical performance of Li-rich layered oxide cathode materials were strongly dependent on calcination temperatures. The results suggest that a calcination temperature in a range of 850–900 °C could promote electrochemical performance of this type of cathode materials.

  9. Effect of calcination temperature on microstructure and electrochemical performance of lithium-rich layered oxide cathode materials

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Quanxin; Peng, Fangwei; Li, Ruhong; Yin, Shibo; Dai, Changsong, E-mail: changsd@hit.edu.cn

    2016-11-15

    Highlights: • A series of Li-rich layered oxide cathode materials (Li{sub 1.2}Mn{sub 0.56}Ni{sub 0.16}Co{sub 0.08}O{sub 2}) were successfully synthesized via a two-step synthesis method. • The effects of calcination temperature on the cathode materials were researched in detail. • A well-crystallized layered structure was obtained as the calcination temperature increased. • The samples calcined in a range of 850–900 °C exhibited excellent electrochemical performance. - Abstract: Lithium-rich layered oxide cathode materials (Li{sub 1.2}Mn{sub 0.56}Ni{sub 0.16}Co{sub 0.08}O{sub 2} (LLMO)) were synthesized via a two-step synthesis method involving co-precipitation and high-temperature calcination. The effects of calcination temperature on the cathode materials were studied in detail. Structural and morphological characterizations revealed that a well-crystallized layered structure was obtained at a higher calcination temperature. Electrochemical performance evaluation revealed that a cathode material obtained at a calcination temperature of 850 °C delivered a high initial discharge capacity of 266.8 mAh g{sup −1} at a 0.1 C rate and a capacity retention rate of 95.8% after 100 cycles as well as excellent rate capability. Another sample calcinated at 900 °C exhibited good cycling stability. It is concluded that the structural stability and electrochemical performance of Li-rich layered oxide cathode materials were strongly dependent on calcination temperatures. The results suggest that a calcination temperature in a range of 850–900 °C could promote electrochemical performance of this type of cathode materials.

  10. Ternary CNTs@TiO2/CoO Nanotube Composites: Improved Anode Materials for High Performance Lithium Ion Batteries

    Science.gov (United States)

    Madian, Mahmoud; Ummethala, Raghunandan; Abo El Naga, Ahmed Osama; Ismail, Nahla; Rümmeli, Mark Hermann; Eychmüller, Alexander; Giebeler, Lars

    2017-01-01

    TiO2 nanotubes (NTs) synthesized by electrochemical anodization are discussed as very promising anodes for lithium ion batteries, owing to their high structural stability, high surface area, safety, and low production cost. However, their poor electronic conductivity and low Li+ ion diffusivity are the main drawbacks that prevent them from achieving high electrochemical performance. Herein, we report the fabrication of a novel ternary carbon nanotubes (CNTs)@TiO2/CoO nanotubes composite by a two-step synthesis method. The preparation includes an initial anodic fabrication of well-ordered TiO2/CoO NTs from a Ti-Co alloy, followed by growing of CNTs horizontally on the top of the oxide films using a simple spray pyrolysis technique. The unique 1D structure of such a hybrid nanostructure with the inclusion of CNTs demonstrates significantly enhanced areal capacity and rate performances compared to pure TiO2 and TiO2/CoO NTs, without CNTs tested under identical conditions. The findings reveal that CNTs provide a highly conductive network that improves Li+ ion diffusivity, promoting a strongly favored lithium insertion into the TiO2/CoO NT framework, and hence resulting in high capacity and an extremely reproducible high rate capability. PMID:28773032

  11. Ternary CNTs@TiO2/CoO Nanotube Composites: Improved Anode Materials for High Performance Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Mahmoud Madian

    2017-06-01

    Full Text Available TiO2 nanotubes (NTs synthesized by electrochemical anodization are discussed as very promising anodes for lithium ion batteries, owing to their high structural stability, high surface area, safety, and low production cost. However, their poor electronic conductivity and low Li+ ion diffusivity are the main drawbacks that prevent them from achieving high electrochemical performance. Herein, we report the fabrication of a novel ternary carbon nanotubes (CNTs@TiO2/CoO nanotubes composite by a two-step synthesis method. The preparation includes an initial anodic fabrication of well-ordered TiO2/CoO NTs from a Ti-Co alloy, followed by growing of CNTs horizontally on the top of the oxide films using a simple spray pyrolysis technique. The unique 1D structure of such a hybrid nanostructure with the inclusion of CNTs demonstrates significantly enhanced areal capacity and rate performances compared to pure TiO2 and TiO2/CoO NTs, without CNTs tested under identical conditions. The findings reveal that CNTs provide a highly conductive network that improves Li+ ion diffusivity, promoting a strongly favored lithium insertion into the TiO2/CoO NT framework, and hence resulting in high capacity and an extremely reproducible high rate capability.

  12. Characterization of positive electrode/electrolyte interphase in lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Dupre, N.; Martin, J.F.; Soudan, P.; Guyomard, D. [Inst.des Materiaux Jean Rouxel, Nantes (France)

    2008-07-01

    Lithium batteries appear to be the most viable energy source for portable electronic devices because of their energy density. The solid electrolyte interphase (SEI) between the negative electrode and the electrolyte of a Li-ion battery monitors the overall battery behaviour in terms of irreversible capacity loss, charge transfer kinetics and storage properties. This paper reported on a study that examined the influence of the storage atmosphere and the formation of a protective surface layer on the electrochemical performance. The objective was to better understand the interfacial problems controlling the long term life duration and cyclability. The positive/electrolyte interphase evolution was followed upon aging/cycling using 7Li MAS NMR, XPS and impedance spectroscopy. This very novel and uncommon technique was used to characterize the growth and evolution of the surface of some electrode materials for lithium batteries, due to contact with the ambient atmosphere or electrolyte or along electrochemical cycling. LiFePO4 and LiMn0.5Ni0.5O2 were chosen for the studies because they are among the most promising candidates for positive electrodes for future lithium batteries. The reaction of LiMn0.5Ni0.5O2 with the ambient atmosphere or LiPF6 electrolyte is extremely fast and leads to an important amount of lithium-containing diamagnetic species. The NMR spectra provided valuable structural information on the interaction between the interphase and the active material after contact with electrolyte or along electrochemical cycling. MAS NMR was shown to be a very promising tool to monitor phenomena taking place at the interface between electrode and electrolyte in lithium batteries. The study showed the affect of the potential on the strength of the interaction between the surface layer and the active material and the partial removal of this layer along the electrochemical cycling. 11 refs.

  13. Polymer Electrolytes for Lithium/Sulfur Batteries

    Directory of Open Access Journals (Sweden)

    The Nam Long Doan

    2012-08-01

    Full Text Available This review evaluates the characteristics and advantages of employing polymer electrolytes in lithium/sulfur (Li/S batteries. The main highlights of this study constitute detailed information on the advanced developments for solid polymer electrolytes and gel polymer electrolytes, used in the lithium/sulfur battery. This includes an in-depth analysis conducted on the preparation and electrochemical characteristics of the Li/S batteries based on these polymer electrolytes.

  14. Nanoscale visualization of redox activity at lithium-ion battery cathodes.

    Science.gov (United States)

    Takahashi, Yasufumi; Kumatani, Akichika; Munakata, Hirokazu; Inomata, Hirotaka; Ito, Komachi; Ino, Kosuke; Shiku, Hitoshi; Unwin, Patrick R; Korchev, Yuri E; Kanamura, Kiyoshi; Matsue, Tomokazu

    2014-11-17

    Intercalation and deintercalation of lithium ions at electrode surfaces are central to the operation of lithium-ion batteries. Yet, on the most important composite cathode surfaces, this is a rather complex process involving spatially heterogeneous reactions that have proved difficult to resolve with existing techniques. Here we report a scanning electrochemical cell microscope based approach to define a mobile electrochemical cell that is used to quantitatively visualize electrochemical phenomena at the battery cathode material LiFePO4, with resolution of ~100 nm. The technique measures electrode topography and different electrochemical properties simultaneously, and the information can be combined with complementary microscopic techniques to reveal new perspectives on structure and activity. These electrodes exhibit highly spatially heterogeneous electrochemistry at the nanoscale, both within secondary particles and at individual primary nanoparticles, which is highly dependent on the local structure and composition.

  15. Lithium-aluminum-magnesium electrode composition

    Science.gov (United States)

    Melendres, Carlos A.; Siegel, Stanley

    1978-01-01

    A negative electrode composition is presented for use in a secondary, high-temperature electrochemical cell. The cell also includes a molten salt electrolyte of alkali metal halides or alkaline earth metal halides and a positive electrode including a chalcogen or a metal chalcogenide as the active electrode material. The negative electrode composition includes up to 50 atom percent lithium as the active electrode constituent and a magnesium-aluminum alloy as a structural matrix. Various binary and ternary intermetallic phases of lithium, magnesium, and aluminum are formed but the electrode composition in both its charged and discharged state remains substantially free of the alpha lithium-aluminum phase and exhibits good structural integrity.

  16. High-Performance Lithium-Air Battery with a Coaxial-Fiber Architecture.

    Science.gov (United States)

    Zhang, Ye; Wang, Lie; Guo, Ziyang; Xu, Yifan; Wang, Yonggang; Peng, Huisheng

    2016-03-24

    The lithium-air battery has been proposed as the next-generation energy-storage device with a much higher energy density compared with the conventional lithium-ion battery. However, lithium-air batteries currently suffer enormous problems including parasitic reactions, low recyclability in air, degradation, and leakage of liquid electrolyte. Besides, they are designed into a rigid bulk structure that cannot meet the flexible requirement in the modern electronics. Herein, for the first time, a new family of fiber-shaped lithium-air batteries with high electrochemical performances and flexibility has been developed. The battery exhibited a discharge capacity of 12,470 mAh g(-1) and could stably work for 100 cycles in air; its electrochemical performances were well maintained under bending and after bending. It was also wearable and formed flexible power textiles for various electronic devices. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Effect of pre-lithiation degrees of mesocarbon microbeads anode on the electrochemical performance of lithium-ion capacitors

    International Nuclear Information System (INIS)

    Zhang, Jin; Shi, Zhiqiang; Wang, Chengyang

    2014-01-01

    Highlights: • MCMB with different pre-lithiation capacity as negative electrode in LIC. • Pre-lithiation improves the electrochemical performance of LIC. • The optimal pre-lithiation capacity has been proposed. - Abstract: Lithium ion capacitors are assembled with pre-lithiated mesocarbon microbeads (LMCMB) anode and activated carbon (AC) cathode. The effect of pre-lithiation degrees on the crystal structure of MCMB electrode and the electrochemical capacitance behavior of LIC are investigated by X-ray diffraction (XRD) and the charge-discharge test of three-electrode cell. The structure of graphite still maintained when the pre-lithiation capacity is less than 200 mAh g −1 , phase transition takes place with the increase of pre-lithiation capacity from 250 mAh g −1 to 350 mAh g −1 . Pre-lithiation degrees of MCMB anode greatly affect the charge-discharge process and behavior, which impact on the electrochemical performance of LIC. The LIC with pre-lithiation capacity of 300 mAh g −1 has the optimal electrochemical performance. The energy density of LIC300 is up to 92.3 Wh kg −1 , the power density as high as 5.5 kW kg −1 and the capacity retention is 97.0% after 1000 cycles. The excellent electrochemical performance benefits from the appropriate pre-lithiation capacity of negative electrode. The appropriate pre-lithiation ensures the working voltage of negative electrode in low and relative stable charge-discharge platform corresponding to the mutual phase transition from the second stage graphite intercalation compound (LiC 12 ) to the first stage graphite intercalation compound (LiC 6 ). The stable charge-discharge platform of negative electrode is conductive to the sufficient utilization of AC positive electrode

  18. Kinetic Monte Carlo Study of Ambipolar Lithium Ion and Electron-Polaron Diffusion into Nanostructured TiO2

    International Nuclear Information System (INIS)

    Yu, Jianguo; Sushko, Maria L.; Kerisit, Sebastien N.; Rosso, Kevin M.; Liu, Jun

    2012-01-01

    Nanostructured titania (TiO2) polymorphs have proved to be promising electrode materials for next generation lithium-ion batteries. However, there is still a lack of understanding of the fundamental microscopic processes that control charge transport in these materials. Here we present microscopic simulations of the collective dynamics of lithium-ion (Li+) and charge compensating electron polarons (e-) in rutile TiO2 nanoparticles in contact with idealized conductive matrix and electrolyte. Kinetic Monte Carlo simulations are used, parameterized by molecular dynamics-based predictions of activation energy barriers for Li+ and e- diffusion. Simulations reveal the central role of electrostatic coupling between Li+ and e- on their collective drift diffusion at the nanoscale. They also demonstrate that high contact area between conductive matrix and rutile nanoparticles leads to undesirable coupling-induced surface saturation effects during Li+ insertion, which limits the overall capacity and conductivity of the material. These results help provide guidelines for design of nanostructured electrode materials with improved electrochemical performance.

  19. Designer interphases for the lithium-oxygen electrochemical cell

    KAUST Repository

    Choudhury, Snehashis

    2017-04-20

    An electrochemical cell based on the reversible oxygen reduction reaction: 2Li+ + 2e− + O2 ↔ Li2O2, provides among the most energy dense platforms for portable electrical energy storage. Such Lithium-Oxygen (Li-O2) cells offer specific energies competitive with fossil fuels and are considered promising for electrified transportation. Multiple, fundamental challenges with the cathode, anode, and electrolyte have limited practical interest in Li-O2 cells because these problems lead to as many practical shortcomings, including poor rechargeability, high overpotentials, and specific energies well below theoretical expectations. We create and study in-situ formation of solid-electrolyte interphases (SEIs) based on bromide ionomers tethered to a Li anode that take advantage of three powerful processes for overcoming the most stubborn of these challenges. The ionomer SEIs are shown to protect the Li anode against parasitic reactions and also stabilize Li electrodeposition during cell recharge. Bromine species liberated during the anchoring reaction also function as redox mediators at the cathode, reducing the charge overpotential. Finally, the ionomer SEI forms a stable interphase with Li, which protects the metal in high Gutmann donor number liquid electrolytes. Such electrolytes have been reported to exhibit rare stability against nucleophilic attack by Li2O2 and other cathode reaction intermediates, but also react spontaneously with Li metal anodes. We conclude that rationally designed SEIs able to regulate transport of matter and ions at the electrolyte/anode interface provide a promising platform for addressing three major technical barriers to practical Li-O2 cells.

  20. Designer interphases for the lithium-oxygen electrochemical cell

    KAUST Repository

    Choudhury, Snehashis; Wan, Charles Tai-Chieh; Al Sadat, Wajdi I.; Tu, Zhengyuan; Lau, Sampson; Zachman, Michael J.; Kourkoutis, Lena F.; Archer, Lynden A.

    2017-01-01

    An electrochemical cell based on the reversible oxygen reduction reaction: 2Li+ + 2e− + O2 ↔ Li2O2, provides among the most energy dense platforms for portable electrical energy storage. Such Lithium-Oxygen (Li-O2) cells offer specific energies competitive with fossil fuels and are considered promising for electrified transportation. Multiple, fundamental challenges with the cathode, anode, and electrolyte have limited practical interest in Li-O2 cells because these problems lead to as many practical shortcomings, including poor rechargeability, high overpotentials, and specific energies well below theoretical expectations. We create and study in-situ formation of solid-electrolyte interphases (SEIs) based on bromide ionomers tethered to a Li anode that take advantage of three powerful processes for overcoming the most stubborn of these challenges. The ionomer SEIs are shown to protect the Li anode against parasitic reactions and also stabilize Li electrodeposition during cell recharge. Bromine species liberated during the anchoring reaction also function as redox mediators at the cathode, reducing the charge overpotential. Finally, the ionomer SEI forms a stable interphase with Li, which protects the metal in high Gutmann donor number liquid electrolytes. Such electrolytes have been reported to exhibit rare stability against nucleophilic attack by Li2O2 and other cathode reaction intermediates, but also react spontaneously with Li metal anodes. We conclude that rationally designed SEIs able to regulate transport of matter and ions at the electrolyte/anode interface provide a promising platform for addressing three major technical barriers to practical Li-O2 cells.

  1. Polymer electrolytes based on aromatic lithium sulfonyl-imide compounds; Electrolytes polymeres a base de sulfonylimidures de lithium aromatiques

    Energy Technology Data Exchange (ETDEWEB)

    Reibel, L.; Bayoudh, S. [Centre National de la Recherche Scientifique (CNRS), 67 - Strasbourg (France). Institut Charles Sadron; Baudry, P. [Electricite de France, 77 - Moret sur Loing (France). Direction des Etudes et Recherches; Majastre, H. [Bollore Technologies, 29 - Quimper (France); Herlem, G. [UFR de Sciences et Techniques, L.E.S., 25 - Besancon (France)

    1996-12-31

    This paper presents ionic conductivity results obtained with polymer electrolytes and also with propylene carbonate solutions. The domain of electrochemical activity of this salt has been determined using cycle volt-amperometry in propylene carbonate. Preliminary experiments on the stability of the polymer electrolyte with respect to the lithium electrode have been carried out for a possible subsequent use in lithium batteries. (J.S.) 4 refs.

  2. Polymer electrolytes based on aromatic lithium sulfonyl-imide compounds; Electrolytes polymeres a base de sulfonylimidures de lithium aromatiques

    Energy Technology Data Exchange (ETDEWEB)

    Reibel, L; Bayoudh, S [Centre National de la Recherche Scientifique (CNRS), 67 - Strasbourg (France). Institut Charles Sadron; Baudry, P [Electricite de France, 77 - Moret sur Loing (France). Direction des Etudes et Recherches; Majastre, H [Bollore Technologies, 29 - Quimper (France); Herlem, G [UFR de Sciences et Techniques, L.E.S., 25 - Besancon (France)

    1997-12-31

    This paper presents ionic conductivity results obtained with polymer electrolytes and also with propylene carbonate solutions. The domain of electrochemical activity of this salt has been determined using cycle volt-amperometry in propylene carbonate. Preliminary experiments on the stability of the polymer electrolyte with respect to the lithium electrode have been carried out for a possible subsequent use in lithium batteries. (J.S.) 4 refs.

  3. Graphene-encapsulated cobalt sulfides nanocages with excellent anode performances for lithium ion batteries

    International Nuclear Information System (INIS)

    Guo, Jinxue; Li, Fenfen; Sun, Yanfang; Zhang, Xiao; Tang, Lin

    2015-01-01

    Graphical abstract: Display Omitted -- Highlights: •Graphene wrapped CoS 2 nanocages are synthesized as anode materials. •Layer-by-layer assembled structures are beneficial for fast and stable Li storage. •Hollow features improve capacity, rate capability and cycling life. •The sample shows outstanding lithium storages, especially high-rate performance. -- Abstract: A layer-by-layer assembled composite of graphene nanosheets (GNSs) wrapped monodisperse cobalt sulfides (CoS 2 ) nanocages has been prepared via a solvothermal method. The flexible GNSs in the layered composite act as the effective matrix to encapsulate the monodisperse CoS 2 nanocages, buffer the volume changes and prevent the aggregation of the CoS 2 nanocages during electrochemical cycling. The loosely stacked GNSs, which are induced with the insertion of CoS 2 , are convenient for electrolyte wetting and serve as highway for the rapid electron and lithium transport. The monodisperse nanocages can supply additional space to tolerate the volume changes, shorten lithium diffusion path, and do not tend to aggregate. As a result, the specific sample can deliver a high capacity approaching 800 mA h g −1 after 150 cycles at 100 mA g −1 and 697 mA h g −1 after 300 cycles at 500 mA g −1 , in addition to good capacity retention and excellent rate capability, making it a promising candidate as next-generation anode materials for lithium-ion batteries

  4. Graphene derived carbon confined sulfur cathodes for lithium-sulfur batteries: Electrochemical impedance studies

    International Nuclear Information System (INIS)

    Ganesan, Aswathi; Varzi, Alberto; Passerini, Stefano; Shaijumon, Manikoth M.

    2016-01-01

    Highlights: • Graphene-derived carbon (GDC) with distinctive porosity characteristics are prepared. • Effect of micro-/mesoporosity of GDC for improved Li-S battery performance is studied. • Impedance studies reveal insights into Li-S redox reactions and capacity fading phenomena. - Abstract: Sulfur nanocomposites are prepared by using graphene derived carbon (GDC), with controlled porosity characteristics, as confining matrix and are studied as efficient cathodes for lithium-sulfur (Li-S) batteries. To understand the effect of micro-/mesoporosity in porous carbon for the effective encapsulation of sulfur and polysulfides towards improved Li-S battery performance, two different GDC samples with controlled porosity characteristics, one with predominantly micropores (GDC-1) and a surface area of 1970 m 2 g −1 and the other with a surface area of 3239 m 2 g −1 , having more or less equal contribution of micro- and mesopores (GDC-2), are used to synthesize nanocomposite sulfur electrodes following melt diffusion process. Electrochemical studies are carried out by using cyclic voltammetry, galvanostatic charge/discharge cycling and electrochemical impedance spectroscopy (EIS). EIS spectra collected at different depth of discharge (DOD) in the first cycle as well as upon cycling give valuable insights into the Li-S redox reactions and capacity fading phenomena in these electrodes. The impedance response of GDC-S electrodes suggests a detrimental effect of the mesopores, where insoluble reaction products can easily accumulate, resulting in the loss of active material leading to capacity fading of Li-S cells.

  5. High-performance lithium battery anodes using silicon nanowires.

    Science.gov (United States)

    Chan, Candace K; Peng, Hailin; Liu, Gao; McIlwrath, Kevin; Zhang, Xiao Feng; Huggins, Robert A; Cui, Yi

    2008-01-01

    There is great interest in developing rechargeable lithium batteries with higher energy capacity and longer cycle life for applications in portable electronic devices, electric vehicles and implantable medical devices. Silicon is an attractive anode material for lithium batteries because it has a low discharge potential and the highest known theoretical charge capacity (4,200 mAh g(-1); ref. 2). Although this is more than ten times higher than existing graphite anodes and much larger than various nitride and oxide materials, silicon anodes have limited applications because silicon's volume changes by 400% upon insertion and extraction of lithium which results in pulverization and capacity fading. Here, we show that silicon nanowire battery electrodes circumvent these issues as they can accommodate large strain without pulverization, provide good electronic contact and conduction, and display short lithium insertion distances. We achieved the theoretical charge capacity for silicon anodes and maintained a discharge capacity close to 75% of this maximum, with little fading during cycling.

  6. Vanadium nitride as a novel thin film anode material for rechargeable lithium batteries

    International Nuclear Information System (INIS)

    Sun Qian; Fu Zhengwen

    2008-01-01

    Vanadium mononitride (VN) thin films have been successfully fabricated by magnetron sputtering. Its electrochemical behaviour with lithium was examined by galvanostatic cell cycling and cyclic voltammetry. The capacity of VN was found to be stable above 800 mAh g -1 after 50 cycles. By using ex situ X-ray diffraction, high-resolution transmission electron microscopy and selected area electron diffraction as well as in situ spectroelectrochemical measurements, the electrochemical reaction mechanism of VN with lithium was investigated. The reversible conversion reaction of VN into metal V and Li 3 N was revealed. The high reversible capacity and good stable cycle of VN thin film electrode made it a new promising lithium-ion storage material for future rechargeable lithium batteries

  7. Insights into the electrochemical activity of nanosized α-LiFeO2

    International Nuclear Information System (INIS)

    Morales, J.; Santos-Pena, J.; Trocoli, R.; Franger, S.; Rodriguez-Castellon, E.

    2008-01-01

    In recent work [J. Morales, J. Santos-Pena, Electrochem. Commun. 9 (2007) 2116], we prepared nanosized α-LiFeO 2 with increased electrochemical activity in lithium cells relative to various lithium ferrite polymorphs. In this work, we studied the previous electrodes in different charge states in order to obtain a more accurate picture of the phenomena occurring during cycling. Exsitu X-ray photoelectron spectroscopy (XPS) measurements confirmed the oxidation/reduction of iron atoms during the charge/discharge process. The electrochemical impedance spectroscopy results suggested that the electrolyte is not oxidised during the first charge, but rather than a solid electrolyte interface is formed after one cycle. Also, thermal tests revealed that Fe(IV) present in the electrodes reacted with the electrolyte to form oxidised carbon species. Finally, α-LiFeO 2 was tested as a positive electrode material in a lithium battery under different regimes. Stabilised capacities up to 150 mAh g -1 were obtained under a C/4 regime. This lithium ferrite is therefore an attractive alternative to LiCoO 2

  8. Synthesis and electrochemical performances of amorphous carbon-coated Sn-Sb particles as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Wang Zhong; Tian Wenhuai; Liu Xiaohe; Yang Rong; Li Xingguo

    2007-01-01

    The amorphous carbon coating on the Sn-Sb particles was prepared from aqueous glucose solutions using a hydrothermal method. Because the outer layer carbon of composite materials is loose cotton-like and porous-like, it can accommodate the expansion and contraction of active materials to maintain the stability of the structure, and hinder effectively the aggregation of nano-sized alloy particles. The as-prepared composite materials show much improved electrochemical performances as anode materials for lithium-ion batteries compared with Sn-Sb alloy and carbon alone. This amorphous carbon-coated Sn-Sb particle is extremely promising anode materials for lithium secondary batteries and has a high potentiality in the future use. - Graphical abstract: The amorphous carbon coating on the Sn-Sb particles was prepared from aqueous glucose solutions using a hydrothermal method. Because the outer layer carbon of composite materials is loose cotton-like and porous-like, it can accommodate the expansion and contraction of active materials to maintain the stability of the structure, and hinder effectively the aggregation of nano-sized alloy particles

  9. Electrochemical Properties of LLTO/Fluoropolymer-Shell Cellulose-Core Fibrous Membrane for Separator of High Performance Lithium-Ion Battery

    Directory of Open Access Journals (Sweden)

    Fenglin Huang

    2016-01-01

    Full Text Available A superfine Li0.33La0.557TiO3 (LLTO, 69.4 nm was successfully synthesized by a facile solvent-thermal method to enhance the electrochemical properties of the lithium-ion battery separator. Co-axial nanofiber of cellulose and Poly(vinylidene fluoride-co-hexafluoropropylene (PVDF-HFP was prepared by a co-axial electrospinning technique, in which the shell material was PVDF-HFP and the core was cellulose. LLTO superfine nanoparticles were incorporated into the shell of the PVDF-HFP. The core–shell composite nanofibrous membrane showed good wettability (16.5°, contact angle, high porosity (69.77%, and super electrolyte compatibility (497%, electrolyte uptake. It had a higher ionic conductivity (13.897 mS·cm−1 than those of pure polymer fibrous membrane and commercial separator. In addition, the rate capability (155.56 mAh·g−1 was also superior to the compared separator. These excellent performances endowed LLTO composite nanofibrous membrane as a promising separator for high-performance lithium-ion batteries.

  10. Electrochemical oxidation of organic carbonate based electrolyte solutions at lithium metal oxide electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Imhof, R; Novak, P [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    The oxidative decomposition of carbonate based electrolyte solutions at practical lithium metal oxide composite electrodes was studied by differential electrochemical mass spectrometry. For propylene carbonate (PC), CO{sub 2} evolution was detected at LiNiO{sub 2}, LiCoO{sub 2}, and LiMn{sub 2}O{sub 4} composite electrodes. The starting point of gas evolution was 4.2 V vs. Li/Li{sup +} at LiNiO{sub 2}, whereas at LiCoO{sub 2} and LiMn{sub 2}O{sub 4}, CO{sub 2} evolution was only observed above 4.8 V vs. Li/Li{sup +}. In addition, various other volatile electrolyte decomposition products of PC were detected when using LiCoO{sub 2}, LiMn{sub 2}O4, and carbon black electrodes. In ethylene carbonate / dimethyl carbonate, CO{sub 2} evolution was only detected at LiNiO{sub 2} electrodes, again starting at about 4.2 V vs. Li/Li{sup +}. (author) 3 figs., 2 refs.

  11. Lithium thionyl chloride battery

    Energy Technology Data Exchange (ETDEWEB)

    Saathoff, D.J.; Venkatasetty, H.V.

    1982-10-19

    The discharge rate and internal conductivity of electrochemical cell including a lithium anode, and a cathode and an electrolyte including LiAlCl4 and SOC2 is improved by the addition of an amount of a mixture containing AlCl3 and butyl pyridinium chloride.

  12. Non-aqueous electrolytes for lithium ion batteries

    Science.gov (United States)

    Chen, Zonghai; Amine, Khalil

    2015-11-12

    The present invention is generally related to electrolytes containing anion receptor additives to enhance the power capability of lithium-ion batteries. The anion receptor of the present invention is a Lewis acid that can help to dissolve LiF in the passivation films of lithium-ion batteries. Accordingly, one aspect the invention provides electrolytes comprising a lithium salt; a polar aprotic solvent; and an anion receptor additive; and wherein the electrolyte solution is substantially non-aqueous. Further there are provided electrochemical devices employing the electrolyte and methods of making the electrolyte.

  13. A Combined Thermodynamics & Computational Method to Assess Lithium Composition in Anode and Cathode of Lithium Ion Batteries

    International Nuclear Information System (INIS)

    Zhang, Wenyu; Jiang, Lianlian; Van Durmen, Pauline; Saadat, Somaye; Yazami, Rachid

    2016-01-01

    With aim to address the open question of accurate determination of lithium composition in anode and cathode at a defined state of charge (SOC) of lithium ion batteries (LIB), we developed a method combining electrochemical thermodynamic measurements (ETM) and computational data fitting protocol. It is a common knowledge that in a lithium ion battery the SOC of anode and cathode differ from the SOC of the full-cell. Differences are in large part due to irreversible lithium losses within cell and to electrode mass unbalance. This implies that the lithium composition range in anode and in cathode during full charge and discharge cycle in full-cell is different from the composition range achieved in lithium half-cells of anode and cathode over their respective full SOC ranges. To the authors knowledge there is no unequivocal and practical method to determine the actual lithium composition of electrodes in a LIB, hence their SOC. Yet, accurate lithium composition assessment is fundamental not only for understanding the physics of electrodes but also for optimizing cell performances, particularly energy density and cycle life.

  14. High-capacity nanostructured germanium-containing materials and lithium alloys thereof

    Science.gov (United States)

    Graetz, Jason A.; Fultz, Brent T.; Ahn, Channing; Yazami, Rachid

    2010-08-24

    Electrodes comprising an alkali metal, for example, lithium, alloyed with nanostructured materials of formula Si.sub.zGe.sub.(z-1), where 0electrodes made from graphite. These electrodes are useful as anodes for secondary electrochemical cells, for example, batteries and electrochemical supercapacitors.

  15. Lithium salt with a super-delocalized perfluorinated sulfonimide anion as conducting salt for lithium-ion cells: Physicochemical and electrochemical properties

    Science.gov (United States)

    Zhang, Heng; Han, Hongbo; Cheng, Xiaorong; Zheng, Liping; Cheng, Pengfei; Feng, Wenfang; Nie, Jin; Armand, Michel; Huang, Xuejie; Zhou, Zhibin

    2015-11-01

    Lithium salt with a super-delocalized imide anion, namely (trifluoromethane(S-trifluoromethanesulfonylimino)sulfonyl) (trifluoromethanesulfonyl)imide ([CF3SO(=NSO2CF3)2]-), [sTFSI]-), has been prepared and studied as conducting salt for Li-ion cells. The fundamental physicochemical and electrochemical properties of neat Li[sTFSI] and its carbonate-based liquid electrolyte have been characterized with various chemical and electrochemical tools. Li[sTFSI] shows a low melting point at 118 °C, and is thermally stable up to 300 °C without decomposition on the spectra of differential scanning calorimetry-thermogravimetry-mass spectrometry (DSC-TG-MS). The electrolyte of 1.0 M (mol dm-3) Li[sTFSI] in ethylene carbonate (EC)/ethyl-methyl-carbonate (EMC) (3:7, v/v) containing 0.3% water does not show any hydrolytic decomposition on the spectra of 1H and 19F NMR, after storage at 85 °C for 10 days. The conductivities of 1.0 M Li[sTFSI]-EC/EMC (3:7, v/v) are slightly lower than those of Li[(CF3SO2)2N] (LiTFSI), but higher than those of Li[(C2F5SO2)2N] (LiBETI). The electrochemical behavior of Al foil in the Li[sTFSI]-based electrolyte has been investigated by using cyclic voltammetry and chronoamperometry, and scanning electron microscope (SEM). It is illustrated that Al metal does not corrode in the high potential region (3-5 V vs. Li/Li+) in the Li[sTFSI]-based electrolyte. On Pt electrode, the Li[sTFSI]-based electrolyte is highly resistant to oxidation (ca. 5 V vs. Li/Li+), and is also resistant to reduction to allow Li deposition and stripping. The applicability of Li[sTFSI] as conducting salt for Li-ion cells has been tested using graphite/LiCoO2 cells. It shows that the cell with Li[sTFSI] displays better cycling performance than that with LiPF6.

  16. Synthesis of One Dimensional Li2MoO4 Nanostructures and Their Electrochemical Performance as Anode Materials for Lithium-ion Batteries

    International Nuclear Information System (INIS)

    Liu, Xudong; Zhao, Yanming; Dong, Youzhong; Fan, Qinghua; Kuang, Quan; Liang, Zhiyong; Lin, Xinghao; Han, Wei; Li, Qidong; Wen, Mingming

    2015-01-01

    Highlights: • One dimensional Li 2 MoO 4 nanostructures including nanorods and nanotubes have been successfully fabricated via a simple sol-gel method firstly. • Possible crystal formation mechanisms are proposed for these one dimensional Li 2 MoO 4 nanostructures. • These one dimensional Li 2 MoO 4 nanostructure electrode materials present outstanding rate abilities and cycle capabilities in electrochemical performance compared to the carbon-free powder sample when evaluated as anode materials for Lithium-ion batteries. • The carbon-coated Li 2 MoO 4 nanotube electrode improves the charging/discharging capacities of graphite even after applying 60 cycles at very high current density. - Abstract: One dimensional Li 2 MoO 4 nanostructures including nanorods and nanotubes have been successfully fabricated via a simple sol-gel method adding Li 2 CO 3 and MoO 3 powders into distilled water with citric acid as an assistant agent and carbon source. Our experimental results show that the formation of the one dimensional nanostructure morphology is evaporation and crystallization process with self-adjusting into a rod-like hexagonal cross-section structure, while the citric acid played an important role during the formation of Li 2 MoO 4 nanotubes under the acidic environment by capping, stabilizing the {1010} facet of Li 2 MoO 4 structure and controlling the concentration of H + (pH value) of the aqueous solution. Finally, basic electrochemical performance of these one dimensional Li 2 MoO 4 nanostructures including nanorods and nanotubes evaluated as anode materials for lithium-ion batteries (LIBs) are discussed, for comparison, the properties of carbon-free powder sample synthesized by solid-state reaction are also displayed. Experimental results show that different morphology and carbon-coating on the surface have an important influence on electrochemical performance

  17. Effects of ion insertion on cycling performance of miniaturized electrochemical capacitor of carbon nanotubes array.

    Science.gov (United States)

    Tsai, Dah-Shyang; Chang, Chuan-hua; Chiang, Wei-Wen; Lee, Kuei-Yi; Huang, Ying-Sheng

    2014-10-24

    Capacity degradation and ion insertion of a miniaturized electrochemical capacitor are studied using ionic liquid [EMI] [TFSI] as the electrolyte. This capacitor is featured with two comb-like electrodes of vertical carbon nanotubes, ∼70 μm in height and 20 μm in interelectrode gap. We quantify the levels of ion insertion damage with Raman spectroscopy after the electrode experiences 120 consecutive voltammetric cycles to various potential limits. Distinct structural damage emerges due to [EMI] when the negative potential reaches -1.7 V, and those due to [TFSI] arise when the positive potential reaches 1.7 V vs. RHE. Judging from the peak broadenings, [EMI] is more detrimental than [TFSI]. When the voltage window ΔU is set as less than or equal to 2.8 V, both electrode potentials are within the two intercalation limits, little or no decay is observed in 10(4) charge/discharge cycles. When ΔU is 3.4 V, the positive potential exceeds the upper limit, but the negative potential stays within the lower limit, the cell capacitance decreases moderately. When ΔU increases to 3.8 V, both electrodes suffer from damages because of exceeding the intercalation limits. And the cell capacitance decreases substantially, even leading to a premature failure.

  18. Rapid charge-discharge property of Li4Ti5O12-TiO2 nanosheet and nanotube composites as anode material for power lithium-ion batteries.

    Science.gov (United States)

    Yi, Ting-Feng; Fang, Zi-Kui; Xie, Ying; Zhu, Yan-Rong; Yang, Shuang-Yuan

    2014-11-26

    Well-defined Li4Ti5O12-TiO2 nanosheet and nanotube composites have been synthesized by a solvothermal process. The combination of in situ generated rutile-TiO2 in Li4Ti5O12 nanosheets or nanotubes is favorable for reducing the electrode polarization, and Li4Ti5O12-TiO2 nanocomposites show faster lithium insertion/extraction kinetics than that of pristine Li4Ti5O12 during cycling. Li4Ti5O12-TiO2 electrodes also display lower charge-transfer resistance and higher lithium diffusion coefficients than pristine Li4Ti5O12. Therefore, Li4Ti5O12-TiO2 electrodes display lower charge-transfer resistance and higher lithium diffusion coefficients. This reveals that the in situ TiO2 modification improves the electronic conductivity and electrochemical activity of the electrode in the local environment, resulting in its relatively higher capacity at high charge-discharge rate. Li4Ti5O12-TiO2 nanocomposite with a Li/Ti ratio of 3.8:5 exhibits the lowest charge-transfer resistance and the highest lithium diffusion coefficient among all samples, and it shows a much improved rate capability and specific capacity in comparison with pristine Li4Ti5O12 when charging and discharging at a 10 C rate. The improved high-rate capability, cycling stability, and fast charge-discharge performance of Li4Ti5O12-TiO2 nanocomposites can be ascribed to the improvement of electrochemical reversibility, lithium ion diffusion, and conductivity by in situ TiO2 modification.

  19. Na-doped LiMnPO4 as an electrode material for enhanced lithium ...

    Indian Academy of Sciences (India)

    and electrochemical performance. Lithium manganese ... bond enables good thermal and cycling stability [4,5]. The ... Moreover, the surface morphologies are an essential factor ... work, electrochemically inactive cations were replaced par-.

  20. Graphene-Based Composites as Cathode Materials for Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Libao Chen

    2013-01-01

    Full Text Available Owing to the superior mechanical, thermal, and electrical properties, graphene was a perfect candidate to improve the performance of lithium ion batteries. Herein, we review the recent advances in graphene-based composites and their application as cathode materials for lithium ion batteries. We focus on the synthesis methods of graphene-based composites and the superior electrochemical performance of graphene-based composites as cathode materials for lithium ion batteries.

  1. A regenerative electrochemical biosensor for mercury(II) by using the insertion approach and dual-hairpin-based amplification

    International Nuclear Information System (INIS)

    Jia, Jing; Ling, Yu; Gao, Zhong Feng; Lei, Jing Lei; Luo, Hong Qun; Li, Nian Bing

    2015-01-01

    Highlights: • The dual-hairpin structure as a signal amplifier is label-free and handy. • The strategy uses the insertion approach to improve the hybridization efficiency. • This biosensor has a low detection limit (28 pM) for detection of Hg 2+ . • This biosensor can be easily regenerated by using L-cysteine. - Abstract: A simple and effective biosensor for Hg 2+ determination was investigated. The novel biosensor was prepared by the insertion approach that the moiety-labeled DNA inserted into a loosely packed cyclic-dithiothreitol (DTT) monolayer, improving the hybridization efficiency. Electrochemical impedance spectroscopy studies of two biosensors (single-hairpin and dual-hairpin structure DNA modified electrodes) used for Hg 2+ detection indicated that the dual-hairpin modified electrode had a larger electron transfer resistance change (ΔR ct ). Consequently, the dual-hairpin structure was used as a signal amplifier for the preparation of a selective Hg 2+ biosensor. This biosensor exhibited an excellent selectivity toward Hg 2+ over Cd 2+ , Pd 2+ , Co 2+ etc. Also, a linear relation was observed between the ΔR ct and Hg 2+ concentrations in a range from 0.1 nM to 5 μM with a detection limit of 28 pM under optimum conditions. Moreover, the biosensor can be reused by using L-cysteine and successfully applied for detecting Hg 2+ in real samples

  2. Carbon aerogel with 3-D continuous skeleton and mesopore structure for lithium-ion batteries application

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Xiaoqing, E-mail: yxq-886@163.com [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Huang, Hong [Instrumental Analysis and Research Center, Sun Yat-sen University, Guangzhou 510275 (China); Zhang, Guoqing; Li, Xinxi [School of Materials and Energy, Guangdong University of Technology, Guangzhou 510006 (China); Wu, Dingcai [Materials Science Institute, PCFM Laboratory, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China); Fu, Ruowen, E-mail: cesfrw@mail.sysu.edu.cn [Materials Science Institute, PCFM Laboratory, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275 (China)

    2015-01-15

    Carbon aerogel (CA) with 3-D continuous skeleton and mesopore structure was prepared via a microemulsion-templated sol–gel polymerization method and then used as the anode materials of lithium-ion batteries. It was found that the reversible specific capacity of the as-prepared CAs could stay at about 470 mA h g{sup −1} for 80 cycles, much higher than the theoretical capacity of commercial graphite (372 mAh g{sup −1}). In addition, CA also showed a better rate capacity compared to commercial graphite. The good electrochemical properties could be ascribed to the following three factors: (1) the large BET surface area of 620 m{sup 2} g{sup −1}, which can provide more lithium ion insertion sites, (2) 3-D continuous skeleton of CAs, which favors the transport of the electrons, (3) 3-D continuous mesopore structure with narrow mesopore size distribution and high mesopore ratio of 87.3%, which facilitates the diffusion and transport of the electrolyte and lithium ions. - Highlights: • Carbon aerogel (CA) was prepared via a microemulsion-templated sol–gel method. • The CA presents high surface area, 3D continuous skeleton and mesopore structure. • The reversible capacity of CA is much higher than that of graphite.

  3. Carbon aerogel with 3-D continuous skeleton and mesopore structure for lithium-ion batteries application

    International Nuclear Information System (INIS)

    Yang, Xiaoqing; Huang, Hong; Zhang, Guoqing; Li, Xinxi; Wu, Dingcai; Fu, Ruowen

    2015-01-01

    Carbon aerogel (CA) with 3-D continuous skeleton and mesopore structure was prepared via a microemulsion-templated sol–gel polymerization method and then used as the anode materials of lithium-ion batteries. It was found that the reversible specific capacity of the as-prepared CAs could stay at about 470 mA h g −1 for 80 cycles, much higher than the theoretical capacity of commercial graphite (372 mAh g −1 ). In addition, CA also showed a better rate capacity compared to commercial graphite. The good electrochemical properties could be ascribed to the following three factors: (1) the large BET surface area of 620 m 2  g −1 , which can provide more lithium ion insertion sites, (2) 3-D continuous skeleton of CAs, which favors the transport of the electrons, (3) 3-D continuous mesopore structure with narrow mesopore size distribution and high mesopore ratio of 87.3%, which facilitates the diffusion and transport of the electrolyte and lithium ions. - Highlights: • Carbon aerogel (CA) was prepared via a microemulsion-templated sol–gel method. • The CA presents high surface area, 3D continuous skeleton and mesopore structure. • The reversible capacity of CA is much higher than that of graphite

  4. Synthesis of TiO{sub 2} by electrochemical method from TiCl{sub 4} solution as anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Nur, Adrian, E-mail: adriannur@staff.uns.ac.id; Purwanto, Agus; Jumari, Arif; Dyartanti, Endah R.; Sari, Sifa Dian Permata; Hanifah, Ita Nur [Research Group of Advanced Material, Department of Chemical Engineering, Sebelas Maret University, Jl. Ir. Sutami 36 A Kentingan, Surakarta Indonesia 57126 (Indonesia)

    2016-02-08

    Metal oxide combined with graphite becomes interesting composition. TiO{sub 2} is a good candidate for Li ion battery anode because of cost, availability of sufficient materials, and environmentally friendly. TiO{sub 2} gravimetric capacity varied within a fairly wide range. TiO{sub 2} crystals form highly depends on the synthesis method used. The electrochemical method is beginning to emerge as a valuable option for preparing TiO{sub 2} powders. Using the electrochemical method, the particle can easily be controlled by simply adjusting the imposed current or potential to the system. In this work, the effects of some key parameters of the electrosynthesis on the formation of TiO{sub 2} have been investigated. The combination of graphite and TiO{sub 2} particle has also been studied for lithium-ion batteries. The homogeneous solution for the electrosynthesis of TiO{sub 2} powders was TiCl{sub 4} in ethanol solution. The electrolysis was carried out in an electrochemical cell consisting of two carbon electrodes with dimensions of (5 × 2) cm. The electrodes were set parallel with a distance of 2.6 cm between the electrodes and immersed in the electrolytic solution at a depth of 2 cm. The electrodes were connected to the positive and negative terminals of a DC power supply. The electrosynthesis was performed galvanostatically at 0.5 to 2.5 hours and voltages were varied from 8 to 12 V under constant stirring at room temperature. The resulted suspension was aged at 48 hrs, filtered, dried directly in an oven at 150°C for 2 hrs, washed 2 times, and dried again 60 °C for 6 hrs. The particle product has been used to lithium-ion battery as anode. Synthesis of TiO{sub 2} particle by electrochemical method at 10 V for 1 to 2.5 hrs resulted anatase and rutile phase.

  5. Hierarchical architecture of ReS_2/rGO composites with enhanced electrochemical properties for lithium-ion batteries

    International Nuclear Information System (INIS)

    Qi, Fei; Chen, Yuanfu; Zheng, Binjie; He, Jiarui; Li, Qian; Wang, Xinqiang; Lin, Jie; Zhou, Jinhao; Yu, Bo; Li, Pingjian; Zhang, Wanli

    2017-01-01

    Highlights: • The ReS_2/rGO composites have been synthesized by a facile one-pot method. • The ReS_2/rGO composites exhibit hierarchical architecture. • The ReS_2/rGO composites deliver better electrochemical performances than ReS_2. • The enhanced performance is due to porous and conductive structure of ReS_2/rGO. - Abstract: Rhenium disulfide (ReS_2), a two-dimensional (2D) semiconductor, has attracted more and more attention due to its unique anisotropic electronic, optical, mechanical properties. However, the facile synthesis and electrochemical property of ReS_2 and its composite are still necessary to be researched. In this study, for the first time, the ReS_2/reduced graphene oxide (rGO) composites have been synthesized through a facile and one-pot hydrothermal method. The ReS_2/rGO composites exhibit a hierarchical, interconnected, and porous architecture constructed by nanosheets. As anode for lithium-ion batteries, the as-synthesized ReS_2/rGO composites deliver a large initial capacity of 918 mAh g"−"1 at 0.2 C. In addition, the ReS_2/rGO composites exhibit much better electrochemical cycling stability and rate capability than that of bare ReS_2. The significant enhancement in electrochemical property can be attributed to its unique architecture constructed by nanosheets and porous structure, which can allow for easy electrolyte infiltration, efficient electron transfer, and ionic diffusion. Furthermore, the graphene with high electronic conductivity can provide good conductive passageways. The facile synthesis approach can be extended to prepare other 2D transition metal dichalcogenides semiconductors for energy storage and catalytic application.

  6. Polyether matrices for lithium generators; Matrices polyethers pour generateurs au lithium

    Energy Technology Data Exchange (ETDEWEB)

    Alloin, F.; Sanchez, J.Y. [Laboratoire d`Electrochimie et de Physicochimie des Materiaux et des Interfaces, 38 - Saint-Martin-d`Heres (France)

    1996-12-31

    The use of solvating polymers of polyether type is an interesting solution for the manufacturing of high capacity lithium batteries with lithium metal anodes and which can operate at T > 50 deg. C. These operating conditions are perfectly compatible with electric-powered vehicle and stationary battery applications. In order to improve the ionic conductivity of polymer electrolytes, new aprotic and amorphous polyether lattices have been synthesized having a good conductivity but also good thermal, mechanical and electrochemical stabilities. Two type of 3-D polyether lattices obtained by reticulation of linear pre-polymers have been selected as host polymers: unsaturated poly-condensate and unsaturated co-polyethers. (J.S.) 18 refs.

  7. Polyether matrices for lithium generators; Matrices polyethers pour generateurs au lithium

    Energy Technology Data Exchange (ETDEWEB)

    Alloin, F; Sanchez, J Y [Laboratoire d` Electrochimie et de Physicochimie des Materiaux et des Interfaces, 38 - Saint-Martin-d` Heres (France)

    1997-12-31

    The use of solvating polymers of polyether type is an interesting solution for the manufacturing of high capacity lithium batteries with lithium metal anodes and which can operate at T > 50 deg. C. These operating conditions are perfectly compatible with electric-powered vehicle and stationary battery applications. In order to improve the ionic conductivity of polymer electrolytes, new aprotic and amorphous polyether lattices have been synthesized having a good conductivity but also good thermal, mechanical and electrochemical stabilities. Two type of 3-D polyether lattices obtained by reticulation of linear pre-polymers have been selected as host polymers: unsaturated poly-condensate and unsaturated co-polyethers. (J.S.) 18 refs.

  8. Multi-component intermetallic electrodes for lithium batteries

    Science.gov (United States)

    Thackeray, Michael M; Trahey, Lynn; Vaughey, John T

    2015-03-10

    Multi-component intermetallic negative electrodes prepared by electrochemical deposition for non-aqueous lithium cells and batteries are disclosed. More specifically, the invention relates to composite intermetallic electrodes comprising two or more compounds containing metallic or metaloid elements, at least one element of which can react with lithium to form binary, ternary, quaternary or higher order compounds, these compounds being in combination with one or more other metals that are essentially inactive toward lithium and act predominantly, but not necessarily exclusively, to the electronic conductivity of, and as current collection agent for, the electrode. The invention relates more specifically to negative electrode materials that provide an operating potential between 0.05 and 2.0 V vs. metallic lithium.

  9. Nature of the Electrochemical Properties of Sulphur Substituted LiMn2O4 Spinel Cathode Material Studied by Electrochemical Impedance Spectroscopy

    Directory of Open Access Journals (Sweden)

    Monika Bakierska

    2016-08-01

    Full Text Available In this work, nanostructured LiMn2O4 (LMO and LiMn2O3.99S0.01 (LMOS1 spinel cathode materials were comprehensively investigated in terms of electrochemical properties. For this purpose, electrochemical impedance spectroscopy (EIS measurements as a function of state of charge (SOC were conducted on a representative charge and discharge cycle. The changes in the electrochemical performance of the stoichiometric and sulphur-substituted lithium manganese oxide spinels were examined, and suggested explanations for the observed dependencies were given. A strong influence of sulphur introduction into the spinel structure on the chemical stability and electrochemical characteristic was observed. It was demonstrated that the significant improvement in coulombic efficiency and capacity retention of lithium cell with LMOS1 active material arises from a more stable solid electrolyte interphase (SEI layer. Based on EIS studies, the Li ion diffusion coefficients in the cathodes were estimated, and the influence of sulphur on Li+ diffusivity in the spinel structure was established. The obtained results support the assumption that sulphur substitution is an effective way to promote chemical stability and the electrochemical performance of LiMn2O4 cathode material.

  10. Insights into the electrochemical activity of nanosized {alpha}-LiFeO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Morales, J.; Santos-Pena, J.; Trocoli, R. [Departamento de Quimica Inorganica e Ingenieria Quimica, Edificio Marie Curie, Campus de Rabanales, Universidad de Cordoba, Cordoba 14071 (Spain); Franger, S. [Laboratoire de Physico-Chimie de l' Etat Solide, ICMMO, Universite Paris XI, Orsay 91405 (France); Rodriguez-Castellon, E. [Departamento de Quimica Inorganica, Cristalografia y Mineralogia, Campus de Teatinos, Universidad de Malaga, Malaga 29071 (Spain)

    2008-09-20

    In recent work [J. Morales, J. Santos-Pena, Electrochem. Commun. 9 (2007) 2116], we prepared nanosized {alpha}-LiFeO{sub 2} with increased electrochemical activity in lithium cells relative to various lithium ferrite polymorphs. In this work, we studied the previous electrodes in different charge states in order to obtain a more accurate picture of the phenomena occurring during cycling. Exsitu X-ray photoelectron spectroscopy (XPS) measurements confirmed the oxidation/reduction of iron atoms during the charge/discharge process. The electrochemical impedance spectroscopy results suggested that the electrolyte is not oxidised during the first charge, but rather than a solid electrolyte interface is formed after one cycle. Also, thermal tests revealed that Fe(IV) present in the electrodes reacted with the electrolyte to form oxidised carbon species. Finally, {alpha}-LiFeO{sub 2} was tested as a positive electrode material in a lithium battery under different regimes. Stabilised capacities up to 150 mAh g{sup -1} were obtained under a C/4 regime. This lithium ferrite is therefore an attractive alternative to LiCoO{sub 2}. (author)

  11. Efficient Electrolytes for Lithium-Sulfur Batteries

    Directory of Open Access Journals (Sweden)

    Natarajan eAngulakshmi

    2015-05-01

    Full Text Available This review article mainly encompasses on the state-of-the-art electrolytes for lithium–sulfur batteries. Different strategies have been employed to address the issues of lithium-sulfur batteries across the world. One among them is identification of electrolytes and optimization of their properties for the applications in lithium-sulfur batteries. The electrolytes for lithium-sulfur batteries are broadly classified as (i non-aqueous liquid electrolytes, (ii ionic liquids, (iii solid polymer and (iv glass-ceramic electrolytes. This article presents the properties, advantages and limitations of each type of electrolytes. Also the importance of electrolyte additives on the electrochemical performance of Li-S cells is discussed.

  12. Synthesis and electrochemical properties of Li{sub 2}ZnTi{sub 3}O{sub 8} fibers as an anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang Li; Wu Lijuan; Li Zhaohui; Lei Gangtie [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China); Xiao Qizhen, E-mail: qizhenxiao2004@yahoo.com.cn [Key Laboratory of Environmentally Friendly Chemistry and Applications of Ministry of Education, College of Chemistry, Xiangtan University, Hunan 411105 (China); College of Civil Engineering and Mechanics, Xiangtan University, Hunan 411105 (China); Zhang Ping [College of Civil Engineering and Mechanics, Xiangtan University, Hunan 411105 (China)

    2011-06-01

    Highlights: > A simple electrospinning method has been developed to fabricate Li{sub 2}ZnTi{sub 3}O{sub 8} fibers. > Li{sub 2}ZnTi{sub 3}O{sub 8} fibers as anode material for lithium-ion batteries. > A stable and reversible capacity of over 227 mAh g{sup -1} is achieved at a rate of 0.1 C. > Li{sub 2}ZnTi{sub 3}O{sub 8} anode exhibits good cycle performance and high rate capability. - Abstract: Li{sub 2}ZnTi{sub 3}O{sub 8} fibers are synthesized by thermally treating electrospun Zn(CH{sub 3}COO){sub 2}/LiOAc/TBT/PVP fibers and utilized as an energy storage material for rechargeable lithium-ion batteries. The material is characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and thermal analysis. Scanning electron microscopy results show that the Li{sub 2}ZnTi{sub 3}O{sub 8} fibers have an average diameter of 200 nm. Electrochemical properties of the material are evaluated using cyclic voltammetry, galvanostatic cycling and electrochemical impedance spectroscopy. The results show that as-prepared Li{sub 2}ZnTi{sub 3}O{sub 8} has a high specific discharge capacity of 227.6 mAh g{sup -1} at the 2nd cycle. Its electrochemical performance at subsequent cycles shows good cycling capacity and rate capability. The obtained results thus strongly support that the electrospinning method is an effective method to prepare Li{sub 2}ZnTi{sub 3}O{sub 8} anode material with higher capacity and rate capability.

  13. Thin films of lithium manganese oxide spinel as cathode materials for secondary lithium batteries

    International Nuclear Information System (INIS)

    Shui, J.L.; Jiang, G.S.; Xie, S.; Chen, C.H.

    2004-01-01

    The miniaturization of rechargeable lithium-ion batteries requires high quality thin-film electrodes. Electrostatic spray deposition (ESD) technique was used to fabricate LiMn 2 O 4 thin-film electrodes with three different morphologies: sponge-like porous, fractal-like porous, and dense structures. X-ray diffraction (XRD) and scanning electron microscopy were used to analyze the structures of the electrodes. These electrodes were made into coin cells against metallic lithium for electrochemical characterization. Galvanostatic cycling of the cells revealed different rate capability for the cells with LiMn 2 O 4 electrodes of different morphologies. It is found that the cells with LiMn 2 O 4 electrodes of porous, especially the sponge-like porous, morphology better rate capability than those with dense LiMn 2 O 4 electrodes. Electrochemical impedance spectroscopy (EIS) study indicates that the large surface area of the porous electrodes should be attributed to the smaller interfacial resistance and better rate capability

  14. Electrochemical behavior of lithium imide/cyclic ether electrolytes for 4 V lithium metal rechargeable batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang, X.; Yasukawa, Eiki; Mori, Shoichiro

    1999-11-01

    To develop organic electrolytes for 4 V lithium metal rechargeable batteries, LiN(SO{sub 2}CF{sub 3}){sub 2} electrolytes with five-, six-, and seven-membered cyclic ether solvents were characterized. Among these examined electrolytes, LiN(SO{sub 2}CF{sub 3}){sub 2}/tetrahydropyran (THP) electrolyte was found to possess the most advantages, such as high cycling efficiency, good oxidation stability, and high boiling point. Furthermore, lithium cycling efficiency and conductivity were improved by mixing 50% ethylene carbonate (EC) in 1 mol/dm{sup 3} LiN(SO{sub 2}CF{sub 3}){sub 2}/THP electrolyte. By using LiN(SO{sub 2}C{sub 2}F{sub 5}){sub 2} solute as an alternative to LiN(SO{sub 2}CF{sub 3}){sub 2} in EC + THP (1:1) electrolyte, corrosion of the aluminum current collector was inhibited and therefore, excellent cycling performance of a Li/LiMn{sub 2}O{sub 4} coin cell was realized. It was also found that lithium cycling efficiency increased with decreasing deposition current density or increasing dissolution current density. Especially at deposition/dissolution current densities of 0.2/0.6 mA/cm{sup 2}, the observed lithium cycling efficiency in 1 mol/dm{sup 3} LiN(SO{sub 2}C{sub 2}F{sub 5}){sub 2}/EC + THP (1:1) electrolyte was above 99%. Thermal tests further disclosed that this mixed electrolyte has good thermal stability even in the presence of lithium metal or cathode materials.

  15. A MEMS platform for in situ, real-time monitoring of electrochemically induced mechanical changes in lithium-ion battery electrodes

    International Nuclear Information System (INIS)

    Pomerantseva, Ekaterina; Jung, Hyun; Gnerlich, Markus; Baron, Sergio; Gerasopoulos, Konstantinos; Ghodssi, Reza

    2013-01-01

    We report the first successful demonstration of an optical microelectromechanical systems (MEMS) sensing platform for the in situ characterization of electrochemically induced reversible mechanical changes in lithium-ion battery (LIB) electrodes. The platform consists of an array of flexible membranes with a reflective surface on one side and a thin-film LIB electrode on the other side. The membranes deflect due to the active battery material volume change caused by lithium intercalation (expansion) and extraction (contraction). This deflection is monitored using the Fabry–Perot optical interferometry principle. The active material volume change causes high internal stresses and mechanical degradation of the electrodes. The stress evolution observed in a silicon thin-film electrode incorporated into this MEMS platform follows a ‘first elastic, then plastic’ deformation scheme. Understanding of the internal stresses in battery electrodes during discharge/charge is important for improving the reliability and cycle lifetime of LIBs. The developed MEMS platform presents a new method for in situ diagnostics of thin-film LIB electrodes to aid the development of new materials, optimization of electrode performance, and prevention of battery failure. (paper)

  16. NaLaTi_2O_6 nanosheet as a potential anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Geng, Qiao; Cao, Liyun; Kong, Xingang; Xu, Zhanwei; Huang, Jianfeng; Li, Jiayin; Cheng, Yayi

    2016-01-01

    Highlights: • NaLaTi_2O_6 nanosheet was achieved by a simple one-step hydrothermal method. • NaLaTi_2O_6 was reported for the first time as an anode material. • NaLaTi_2O_6 shown a high discharge capacity of about 180 mAh/g at 100 mA/g. - Abstract: NaLaTi_2O_6 nanosheet was achieved by one-step hydrothermal method and was reported for the first time as an anode material for lithium ion batteries. The phase structure and morphology analysis reveals that pure pervoskite NaLaTi_2O_6 possesses nanosheet morphology with thickness of about 20 nm and length of several hundred nanometers. The electrochemical performances demonstrate that NaLaTi_2O_6 has a good lithium ion insertion/extraction ability with a discharge capacity of about 180 mAh/g, which is slightly larger than Li_4Ti_5O_1_2 theoretical capacity (175 mAh/g). Even more, after 1000 charge-discharge cycles at 100 mA/g, it still maintains a discharge capacity of 165 mAh/g, suggesting that NaLaTi_2O_6 could be explored as a potential anode material for lithium ion batteries.

  17. Synthesis of hollandite-type Li yMn 1- xCo xO 2 (x = 0-0.15) by Li + ion-exchange in molten salt and the electrochemical property for rechargeable lithium battery electrodes

    Science.gov (United States)

    Kumagai, Naoaki; Oshitari, Satoru; Komaba, Shinichi; Kadoma, Yoshihiro

    The Li + ion-exchange reaction of K +-type α-K 0.14MnO 1.93·0.18H 2O and its Co-doped α-K 0.14(Mn 0.85Co 0.15)O 1.96·0.21H 2O with a large (2 × 2) tunnel structure has been investigated in a LiNO 3/LiCl molten salt at 300 °C. The Li + ion-exchanged products were examined by chemical analysis, X-ray diffraction, and scanning and transmission electron microscopic measurements. Almost all the K + ions and the hydrogens of water molecules in the (2 × 2) tunnel of α-MnO 2 and its Co-doped one were exchanged by Li + ions in the molten salt, resulting in Li +-type α-MnO 2 and its Co-doped one containing Li + ions as well as Li 2O (lithium oxide) in the (2 × 2) tunnel with maintaining the original hollandite structure. The electrochemical properties including charge-discharge cycling of the Li + ion-exchanged α-MnO 2 and its Co-doped samples have been investigated as insertion compounds in the search for new cathode materials for rechargeable lithium batteries. The Li + ion-exchanged α-MnO 2 and its Co-doped samples provided higher capacities than the K +-type parent materials on initial discharge and charge-discharge cyclings, probably due to the structural stabilization with the existence of Li 2O in the (2 × 2) tunnels.

  18. Porous One-Dimensional Nanomaterials: Design, Fabrication and Applications in Electrochemical Energy Storage.

    Science.gov (United States)

    Wei, Qiulong; Xiong, Fangyu; Tan, Shuangshuang; Huang, Lei; Lan, Esther H; Dunn, Bruce; Mai, Liqiang

    2017-05-01

    Electrochemical energy storage technology is of critical importance for portable electronics, transportation and large-scale energy storage systems. There is a growing demand for energy storage devices with high energy and high power densities, long-term stability, safety and low cost. To achieve these requirements, novel design structures and high performance electrode materials are needed. Porous 1D nanomaterials which combine the advantages of 1D nanoarchitectures and porous structures have had a significant impact in the field of electrochemical energy storage. This review presents an overview of porous 1D nanostructure research, from the synthesis by bottom-up and top-down approaches with rational and controllable structures, to several important electrochemical energy storage applications including lithium-ion batteries, sodium-ion batteries, lithium-sulfur batteries, lithium-oxygen batteries and supercapacitors. Highlights of porous 1D nanostructures are described throughout the review and directions for future research in the field are discussed at the end. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Molecular Spring Enabled High-Performance Anode for Lithium Ion Batteries

    Directory of Open Access Journals (Sweden)

    Tianyue Zheng

    2017-11-01

    Full Text Available Flexible butyl interconnection segments are synthetically incorporated into an electronically conductive poly(pyrene methacrylate homopolymer and its copolymer. The insertion of butyl segment makes the pyrene polymer more flexible, and can better accommodate deformation. This new class of flexible and conductive polymers can be used as a polymer binder and adhesive to facilitate the electrochemical performance of a silicon/graphene composite anode material for lithium ion battery application. They act like a “spring” to maintain the electrode mechanical and electrical integrity. High mass loading and high areal capacity, which are critical design requirements of high energy batteries, have been achieved in the electrodes composed of the novel binders and silicon/graphene composite material. A remarkable area capacity of over 5 mAh/cm2 and volumetric capacity of over 1700 Ah/L have been reached at a high current rate of 333 mA/g.

  20. Deposition of lithium on a plasma edge probe in TFTR -- Behavior of lithium-painted walls interacting with edge plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Hirooka, Y. [Univ. of California, San Diego, La Jolla, CA (United States); Ashida, K. [Toyama Univ. (Japan); Kugel, H. [Princeton Univ., NJ (United States)] [and others

    1998-05-01

    Recent observations have indicated that lithium pellet injection wall conditioning plays an important role in achieving the enhanced supershot regime in TFTR. However, little is understood about the behavior of lithium-coated limiter walls, interacting with edge plasmas. In the final campaign of TFTR, a cylindrical carbon fiber composite probe was inserted into the boundary plasma region and exposed to ohmically-heated deuterium discharges with lithium pellet injection. The ion-drift side probe surface exhibits a sign of codeposition of lithium, carbon, oxygen, and deuterium, whereas the electron side essentially indicates high-temperature erosion. It is found that lithium is incorporated in these codeposits in the form of oxide at the concentration of a few percent. In the electron side, lithium has been found to penetrate deeply into the probe material, presumably via rapid diffusion through interplane spaces in the graphite crystalline. Though it is not conclusive, materials mixing in the carbon and lithium system appears to be a key process in successful lithium wall conditioning.

  1. Influence of operational condition on lithium plating for commercial lithium-ion batteries – Electrochemical experiments and post-mortem-analysis

    International Nuclear Information System (INIS)

    Ecker, Madeleine; Shafiei Sabet, Pouyan; Sauer, Dirk Uwe

    2017-01-01

    Highlights: •Investigation of lithium plating to support reliable system integration. •Influence of operational conditions at low temperature on lithium plating. •Comparison of different lithium-ion battery technologies. •Large differences in low-temperature behaviour for different technologies. •Post-mortem analysis reveals inhomogeneous deposition of metallic lithium. -- Abstract: The lifetime and safety of lithium-ion batteries are key requirements for successful market introduction of electro mobility. Especially charging at low temperature and fast charging, known to provoke lithium plating, is an important issue for automotive engineers. Lithium plating, leading both to ageing as well as safety risks, is known to play a crucial role in system design of the application. To gain knowledge of different influence factors on lithium plating, low-temperature ageing tests are performed in this work. Commercial lithium-ion batteries of various types are tested under various operational conditions such as temperature, current, state of charge, charging strategy as well as state of health. To analyse the ageing behaviour, capacity fade and resistance increase are tracked over lifetime. The results of this large experimental survey on lithium plating provide support for the design of operation strategies for the implementation in battery management systems. To further investigate the underlying degradation mechanisms, differential voltage curves and impedance spectra are analysed and a post-mortem analysis of anode degradation is performed for a selected technology. The results confirm the deposition of metallic lithium or lithium compounds in the porous structure and suggest a strongly inhomogeneous deposition over the electrode thickness with a dense deposition layer close to the separator for the considered cell. It is shown that this inhomogeneous deposition can even lead to loss of active material. The plurality of the investigated technologies

  2. International Meeting on Lithium Batteries, Rome, Italy, April 27-29, 1982

    Energy Technology Data Exchange (ETDEWEB)

    1983-04-15

    Topics discussed include the mechanistic aspects of the reactivity of organic electrolytes with lithium, the electrochemistry of a nonaqueous lithium/sulfur cell, chromium oxides as cathodes for lithium cells, and the behavior of various cathode materials for nonaqueous lithium cells. Papers are presented on a reversible graphite-lithium negative electrode for electrochemical generators, on interfacial conduction in lithium iodide containing inert oxides, on the mechanism for ion conduction in alkali metal-polymer complexes, and on Li/SOCl2 cells for high temperature applications. Attention is also given to Raman spectroscopic studies of the structure of electrolytes used in the Li/SOCl2 battery, to surface films on lithium in acetonitrile-sulfur dioxide solutions, and to polarization of the lithium electrode in sulfuryl chloride solutions.

  3. High-rate capability of lithium-ion batteries after storing at elevated temperature

    International Nuclear Information System (INIS)

    Wu, Mao-Sung; Chiang, Pin-Chi Julia

    2007-01-01

    High-rate performances of a lithium-ion battery after storage at elevated temperature are investigated electrochemically by means of three-electrode system. The high-rate capability is decreased significantly after high-temperature storage. A 3 C discharge capacities after room-temperature storage and 60 o C storage are 650 and 20 mAh, respectively. Lithium-ion diffusion in lithium cobalt oxide cathode limits the battery's capacity and the results show that storage temperature changes this diffusion behavior. Transmission electron microscopy (TEM) images show that many defects are directly observed in the cathode after storage compared with the fresh cathode; the structural defects block the diffusion within the particles. Electrochemical impedance and polarization curve indicate that mass-transfer (diffusion) dominates the discharge capacity during high-rate discharge

  4. Classifying the mechanisms of electrochemical shock in ion-intercalation materials

    OpenAIRE

    Woodford, William; Carter, W. Craig; Chiang, Yet-Ming

    2014-01-01

    Electrochemical shock” – the electrochemical cycling-induced fracture of materials – contributes to impedance growth and performance degradation in ion-intercalation batteries, such as lithium-ion. Using a combination of micromechanical models and acoustic emission experiments, the mechanisms of electrochemical shock are identified, classified, and modeled in targeted model systems with different composition and microstructure. A particular emphasis is placed on mechanical degradation occurr...

  5. A regenerative electrochemical biosensor for mercury(II) by using the insertion approach and dual-hairpin-based amplification

    Energy Technology Data Exchange (ETDEWEB)

    Jia, Jing; Ling, Yu; Gao, Zhong Feng [Key Laboratory of Eco-Environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Lei, Jing Lei [College of Chemistry and Chemical Engineering, Chongqing University, Chongqing 400044 (China); Luo, Hong Qun, E-mail: luohq@swu.edu.cn [Key Laboratory of Eco-Environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China); Li, Nian Bing, E-mail: linb@swu.edu.cn [Key Laboratory of Eco-Environments in Three Gorges Reservoir Region (Ministry of Education), School of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715 (China)

    2015-09-15

    Highlights: • The dual-hairpin structure as a signal amplifier is label-free and handy. • The strategy uses the insertion approach to improve the hybridization efficiency. • This biosensor has a low detection limit (28 pM) for detection of Hg{sup 2+}. • This biosensor can be easily regenerated by using L-cysteine. - Abstract: A simple and effective biosensor for Hg{sup 2+} determination was investigated. The novel biosensor was prepared by the insertion approach that the moiety-labeled DNA inserted into a loosely packed cyclic-dithiothreitol (DTT) monolayer, improving the hybridization efficiency. Electrochemical impedance spectroscopy studies of two biosensors (single-hairpin and dual-hairpin structure DNA modified electrodes) used for Hg{sup 2+} detection indicated that the dual-hairpin modified electrode had a larger electron transfer resistance change (ΔR{sub ct}). Consequently, the dual-hairpin structure was used as a signal amplifier for the preparation of a selective Hg{sup 2+} biosensor. This biosensor exhibited an excellent selectivity toward Hg{sup 2+} over Cd{sup 2+}, Pd{sup 2+}, Co{sup 2+} etc. Also, a linear relation was observed between the ΔR{sub ct} and Hg{sup 2+} concentrations in a range from 0.1 nM to 5 μM with a detection limit of 28 pM under optimum conditions. Moreover, the biosensor can be reused by using L-cysteine and successfully applied for detecting Hg{sup 2+} in real samples.

  6. Manganese oxide octahedral molecular sieves as insertion electrodes for rechargeable Mg batteries

    KAUST Repository

    Rasul, Shahid

    2013-11-01

    Magnesium has been inserted electrochemically into manganese oxide octahedral molecular sieves (OMS-5 MnO2) at room temperature. Discharge/charge profiles show that a large amount of Mg, i.e., 0.37 Mg/Mn can be inserted electrochemically using 1 M Mg(ClO4)2/AN electrolyte when OMS-5 is prepared in presence of acetylene black. X-ray diffraction analysis and discharge/charge profiles verify that a solid state solution reaction takes place upon Mg insertion into the host lattice with concurrent reduction of Mn4+ to Mn2+. However, upon each reduction of Mn by Mg insertion and resultant dissolution into electrolyte, decrease in the active compound occurs consequently. A low intrinsic electronic conductivity of OMS-5 was suggested to play a vital role in Mg insertion into the host. © 2013 Elsevier Ltd.

  7. Manganese oxide octahedral molecular sieves as insertion electrodes for rechargeable Mg batteries

    KAUST Repository

    Rasul, Shahid; Suzuki, Shinya; Yamaguchi, Shu; Miyayama, Masaru

    2013-01-01

    Magnesium has been inserted electrochemically into manganese oxide octahedral molecular sieves (OMS-5 MnO2) at room temperature. Discharge/charge profiles show that a large amount of Mg, i.e., 0.37 Mg/Mn can be inserted electrochemically using 1 M Mg(ClO4)2/AN electrolyte when OMS-5 is prepared in presence of acetylene black. X-ray diffraction analysis and discharge/charge profiles verify that a solid state solution reaction takes place upon Mg insertion into the host lattice with concurrent reduction of Mn4+ to Mn2+. However, upon each reduction of Mn by Mg insertion and resultant dissolution into electrolyte, decrease in the active compound occurs consequently. A low intrinsic electronic conductivity of OMS-5 was suggested to play a vital role in Mg insertion into the host. © 2013 Elsevier Ltd.

  8. Improved electrochemical performances of CuO nanotube array prepared via electrodeposition as anode for lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Xiao, Anguo, E-mail: hixiaoanguo@126.com; Zhou, Shibiao; Zuo, Chenggang; Zhuan, Yongbing; Ding, Xiang

    2015-10-15

    Graphical abstract: CuO nanotube array electrodes prepared by electrodeposition method exhibit an excellent lithium ion storage ability as anode of Li-ion battery. - Highlights: • CuO nanotube arrays are synthesized by an electrodeposition method. • CuO nanotube shows a high-rate performance. • CuO nanotube shows an excellent cycling performance. - Abstract: We report a facile strategy to prepared CuO nanotube arrays directly grown on Cu plate through the electrodeposition method. The as-prepared CuO nanotubes show a quasi-cylinder nanostructure with internal diameters of ca. ∼100 nm, external diameters of ca. ∼120 nm, and average length of ∼3 μm. As an anode for lithium ion batteries, the electrochemical properties of the CuO nanotube arrays are investigated by cyclic voltammetry (CV) and galvanostatic charge/discharge tests. Due to the unique nanotube nanostructure, the as-prepared CuO electrodes exhibit good rate performance (550 mAh g{sup −1} at 0.1 C and 464 mAh g{sup −1} at 1 C) and cycling performance (581 mAh g{sup −1} at 0.1 C and 538 mAh g{sup −1} at 0.5 C)

  9. Electrical and electrochemical properties of niobium disulphide

    Energy Technology Data Exchange (ETDEWEB)

    Molenda, J.; Bak, T.; Marzec, J. [Academy of Min. and Metall., Cracow (Poland). Dept. of Chem. of Solids

    1996-07-16

    The electrical conductivity and thermoelectric power measurements of NbS{sub 2} pure and electrochemically doped with lithium, Li{sub x}NbS{sub 2}, were done as a function of temperature (77 to 300 K). The high absolute values of conductivity and their dependence on temperature together with low absolute values of thermoelectric power and their linear increase with temperature indicate metallic properties of niobium disulphide. In case of Li{sub x}NbS{sub 2} the obtained values of electrical conductivity are significantly lower as compared with the starting NbS{sub 2}. The temperature dependence of the thermo-electric power of intercalated niobium disulphide also indicates that metallic properties get worse as the concentration of lithium increases. The modification of the electronic structure of NbS{sub 2} due to lithium intercalation was proposed. The character of the discharge curves in the electrochemical Li/Li{sup +}/Li{sub x}NbS{sub 2} systems was correlated with the electronic properties of niobium disulphide. (orig.) 11 refs.

  10. Nano-Sn embedded in expanded graphite as anode for lithium ion batteries with improved low temperature electrochemical performance

    International Nuclear Information System (INIS)

    Yan, Yong; Ben, Liubin; Zhan, Yuanjie; Huang, Xuejie

    2016-01-01

    Highlights: • Nano-Sn embedded in interlayers of expanded graphite is fabricated. • The graphene/nano-Sn/graphene stacked structure promotes cycling stability of Sn. • The Sn/EG shows improved low temperature electrochemical performance. • Chemical diffusion coefficients of the Sn/EG are obtained by GITT. • The Sn/EG exhibits faster Li-ion intercalation kinetics than graphite. - Abstract: Metallic tin (Sn) used as anode material for lithium ion batteries has long been proposed, but its low temperature electrochemical performance has been rarely concerned. Here, a Sn/C composite with nano-Sn embedded in expanded graphite (Sn/EG) is synthesized. The nano-Sn particles (∼30 nm) are uniformly distributed in the interlayers of expanded graphite forming a tightly stacked layered structure. The electrochemical performance of the Sn/EG, particularly at low temperature, is carefully investigated compared with graphite. At -20 °C, the Sn/EG shows capacities of 200 mAh g −1 at 0.1C and 130 mAh g −1 at 0.2C, which is much superior to graphite (<10 mAh g −1 ). EIS measurements suggest that the charge transfer impedance of the Sn/EG increases less rapidly than graphite with decreasing temperatures, which is responsible for the improved low temperature electrochemical performance. The Li-ion chemical diffusion coefficients of the Sn/EG obtained by GITT are an order of magnitude higher at room temperature than that at -20 °C. Furthermore, the Sn/EG exhibits faster Li-ion intercalation kinetics than graphite in the asymmetric charge/discharge measurements, which shows great promise for the application in electric vehicles charged at low temperature.

  11. Synthesis of bismuth sulfide/reduced graphene oxide composites and their electrochemical properties for lithium ion batteries

    International Nuclear Information System (INIS)

    Zhang, Zhian; Zhou, Chengkun; Huang, Lei; Wang, Xiwen; Qu, Yaohui; Lai, Yanqing; Li, Jie

    2013-01-01

    Graphical abstract: The Bi 2 S 3 /reduced graphene oxide composites were synthesized by a one-pot hydrothermal route and exhibited an extraordinary capacity of 1073.1 mAh g −1 with excellent cycling stability and high rate capability as anode material of lithium ion battery. The enhancement in the electrochemical performance could be attributed to the introduction of RGO sheets that not only buffer the large volume changes during the alloy/dealloy reaction of Li and Bi, but also provide a highly conductive network for rapid electron transport in electrode during electrochemical reaction. -- Highlights: •Bi 2 S 3 /RGO composites were in situ prepared by one-pot hydrothermal route. •The Bi 2 S 3 nanoparticles are homogeneous dispersion on the RGO sheets. •Bi 2 S 3 /RGO exhibits excellent cycling stability and high rate capability. •This work will also of interest for supercapacitor and solar cells. -- Abstract: A simple one-pot hydrothermal route was developed to synthesize bismuth sulfide/reduced graphene oxide composites (Bi 2 S 3 /RGO composites) in this work. The morphology and crystalline structure of the obtained products were investigated by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and high resolution transmission electron microscopy (HRTEM). The results of Raman spectra and Fourier transform infrared (FTIR) spectra demonstrated that graphite oxide (GO) sheets were in situ reduced to a certain extent. Transmission electron microscopy (TEM) observation indicated that the Bi 2 S 3 nanoparticles, with a size of 80–100 nm in length, are anchored on RGO sheets. Electrochemical tests show the Bi 2 S 3 /RGO composite exhibits an extraordinary capacity of 1073.1 mAh g −1 with excellent cycling stability and high rate capability compared to pure Bi 2 S 3 particles prepared by a similar route in the absence of GO. The enhancement in the electrochemical performance could be attributed to the introduction of RGO sheets

  12. Reliable reference electrodes for lithium-ion batteries

    KAUST Repository

    La Mantia, F.; Wessells, C.D.; Deshazer, H.D.; Cui, Yi

    2013-01-01

    Despite the high attention drawn to the lithium-ion batteries by the scientific and industrial community, most of the electrochemical characterization is carried out using poor reference electrodes or even no reference electrode. In this case

  13. A design strategy of large grain lithium-rich layered oxides for lithium-ion batteries cathode

    International Nuclear Information System (INIS)

    Jiang, Xiong; Wang, Zhenhua; Rooney, David; Zhang, Xiaoxue; Feng, Jie; Qiao, Jinshuo; Sun, Wang; Sun, Kening

    2015-01-01

    Highlights: • Ultrasound-assisted mixing lithium was used to synthesize Lithium-rich layered oxides. • Lithium-rich layered oxides composed of large grain had high capacity and high cycling stability. • This unique large grain overcomes stress-induced structural collapse caused by Li-ion insertion/extraction and reduces dissolution of Mn ions. • A new strategy of large grain could be employed to synthesize the other complex architectures for various applications. - Abstract: Li-rich materials are considered the most promising for Li-ion battery cathodes, as high capacity can be achieved. However, poor cycling stability is a critical drawback that leads to poor capacity retention. Here a strategy is used to synthesize a large-grain lithium-rich layered oxides to overcome this difficulty without sacrificing rate capability. This material is designed with micron scale grain with a width of about 300 nm and length of 1–3 μm. This unique structure has a better ability to overcome stress-induced structural collapse caused by Li-ion insertion/extraction and reduce the dissolution of Mn ions, which enable a reversible and stable capacity. As a result, this cathode material delivered a highest discharge capacity of around 308 mAh g −1 at a current density of 30 mA g −1 with retention of 88.3% (according to the highest discharge capacity) after 100 cycles, 190 mAh g −1 at a current density of 300 mA g −1 and almost no capacity fading after 100 cycles. Therefore, Lithium-rich material of large-grain structure is a promising cathode candidate in Lithium-ion batteries with high capacity and high cycle stability for application. This strategy of large grain may furthermore open the door to synthesize the other complex architectures for various applications

  14. Electrochemical characteristics of nc-Si/SiC composite for anode electrode of lithium ion batteries

    International Nuclear Information System (INIS)

    Jeon, Bup Ju; Lee, Joong Kee

    2014-01-01

    Graphical abstract: Cycling performances and coulombic efficiencies of the nc-Si/SiC composite anodes at different CH 4 /SiH 4 mole ratios. -- Highlights: • Our work has focused on irreversible discharge capacity and capacity retention of nc-Si/SiC composite particles. • Particles comprised a mixed construction of nc-Si/SiC structure with dual phases. • The SiC phase acted as retarding media, leading to enhanced cycle stability. -- Abstract: nc-Si/SiC composite particles were prepared as an anode material for lithium ion batteries using a plasma jet with DC arc discharge. The composition of the nc-Si/SiC composite particles was controlled by setting the mole ratio of CH 4 and SiH 4 precursor gases. X-ray diffraction, TEM images, and Raman shift analyses revealed that the synthesized nc-Si/SiC composite particles comprised a construction of nano-nocaled structure with crystalline phases of active silicon, highly disordered amorphous carbon of graphite and crystalline phases of β-SiC. In the experimental range examined, the nc-Si/SiC composite particles showed good coulombic efficiency in comparison with particles high Si–Si bonding content due to the interplay of particles with a small proportion of carbon and the buffering effect against volume expansion by structural stabilization, and played a role as retarding media for the rapid electrochemical reactions of the SiC crystal against lithium

  15. Electrochemical characteristics of nc-Si/SiC composite for anode electrode of lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Jeon, Bup Ju [Department of Energy Resources, Shinhan University, 233-1, Sangpae-dong, Dongducheon, Gyeonggi-do, 483-777 (Korea, Republic of); Lee, Joong Kee, E-mail: leejk@kist.re.kr [Advanced Energy Materials Processing Laboratory, Center for Energy Convergence Research, Green City Technology Institute, Korea Institute of Science and Technology, Hwarangno 14-gil 5, Seongbuk-gu, Seoul 136-791 (Korea, Republic of)

    2014-03-25

    Graphical abstract: Cycling performances and coulombic efficiencies of the nc-Si/SiC composite anodes at different CH{sub 4}/SiH{sub 4} mole ratios. -- Highlights: • Our work has focused on irreversible discharge capacity and capacity retention of nc-Si/SiC composite particles. • Particles comprised a mixed construction of nc-Si/SiC structure with dual phases. • The SiC phase acted as retarding media, leading to enhanced cycle stability. -- Abstract: nc-Si/SiC composite particles were prepared as an anode material for lithium ion batteries using a plasma jet with DC arc discharge. The composition of the nc-Si/SiC composite particles was controlled by setting the mole ratio of CH{sub 4} and SiH{sub 4} precursor gases. X-ray diffraction, TEM images, and Raman shift analyses revealed that the synthesized nc-Si/SiC composite particles comprised a construction of nano-nocaled structure with crystalline phases of active silicon, highly disordered amorphous carbon of graphite and crystalline phases of β-SiC. In the experimental range examined, the nc-Si/SiC composite particles showed good coulombic efficiency in comparison with particles high Si–Si bonding content due to the interplay of particles with a small proportion of carbon and the buffering effect against volume expansion by structural stabilization, and played a role as retarding media for the rapid electrochemical reactions of the SiC crystal against lithium.

  16. Investigation of positive electrode materials based on MnO2 for lithium batteries

    International Nuclear Information System (INIS)

    Le, My Loan Phung; Lam, Thi Xuan Binh; Pham, Quoc Trung; Nguyen, Thi Phuong Thoa

    2011-01-01

    Various composite materials of MnO 2 /C have been synthesized by electrochemical deposition and then used for the synthesis of lithium manganese oxide (LiMn 2 O 4 ) spinel as a cathode material for lithium ion batteries. The structure and electrochemical properties of electrode materials based on MnO 2 /C, spinel LiMn 2 O 4 and doped spinel LiNi 0.5 Mn 1.5 O 4 have been studied. The influence of synthesis conditions on the structural and electrochemical properties of synthesized materials was investigated by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electronic microscopy (TEM) and charge–discharge experiments. Some of the studied materials exhibit good performance of cycling and discharge capacity

  17. Superior lithium storage performance of hierarchical porous vanadium pentoxide nanofibers for lithium ion battery cathodes

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Bo [Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); National Key Laboratory of Power Sources, Tianjin Institute of Power Sources, Tianjin 300381 (China); Li, Xifei, E-mail: xfli2011@hotmail.com [Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Bai, Zhimin, E-mail: zhimibai@cugb.edu.cn [Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing 100083 (China); Li, Minsi [Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026 (China); Dong, Lei; Xiong, Dongbin [Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Li, Dejun, E-mail: dejunli@mail.tjnu.edu.cn [Energy & Materials Engineering Centre, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China)

    2015-06-15

    Highlights: • Hierarchical porous vanadium pentoxide nanofibers were synthesized by electrospinning. • V{sub 2}O{sub 5} nanofibers showed much enhanced lithium storage performance. • Kinetics process of electrospinning V{sub 2}O{sub 5} nanofibers was studied by means of EIS for the first time. • Strategies to enhance the electrochemical performance of V{sub 2}O{sub 5} electrode were concluded. - Abstract: The hierarchical V{sub 2}O{sub 5} nanofibers cathode materials with diameter of 200–400 nm are successfully synthesized via an electrospinning followed by annealing. Powder X-ray diffraction (XRD) pattern confirms the formation of phase-pure product. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) obviously display the hierarchical porous nanofibers constructed by attached tiny vanadium oxide nanoplates. Electrochemical behavior of the as-prepared product is systematically studied using galvanostatic charge/discharge testing, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). It turns out that in comparison to the commercial V{sub 2}O{sub 5} and other unique nanostructured materials in the literature, our V{sub 2}O{sub 5} nanofibers show much enhanced lithium storage capacity, improved cyclic stability, and higher rate capability. After 100 cycles at a current density of 800 mA g{sup −1}, the specific capacity of the V{sub 2}O{sub 5} nanofibers retain 133.9 mAh g{sup −1}, corresponding to high capacity retention of 96.05%. More importantly, the EIS at various discharge depths clearly reveal the kinetics process of the V{sub 2}O{sub 5} cathode reaction with lithium. Based on our results, the possible approach to improve the specific capacity and rate capability of the V{sub 2}O{sub 5} cathode material is proposed. It is expected that this study could accelerate the development of V{sub 2}O{sub 5} cathode in rechargeable lithium ion batteries.

  18. Lithium batteries: Status, prospects and future

    International Nuclear Information System (INIS)

    Scrosati, Bruno; Garche, Juergen

    2010-01-01

    Lithium batteries are characterized by high specific energy, high efficiency and long life. These unique properties have made lithium batteries the power sources of choice for the consumer electronics market with a production of the order of billions of units per year. These batteries are also expected to find a prominent role as ideal electrochemical storage systems in renewable energy plants, as well as power systems for sustainable vehicles, such as hybrid and electric vehicles. However, scaling up the lithium battery technology for these applications is still problematic since issues such as safety, costs, wide operational temperature and materials availability, are still to be resolved. This review focuses first on the present status of lithium battery technology, then on its near future development and finally it examines important new directions aimed at achieving quantum jumps in energy and power content. (author)

  19. Novel lithium iron phosphate materials for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Popovic, Jelena

    2011-06-15

    Conventional energy sources are diminishing and non-renewable, take million years to form and cause environmental degradation. In the 21st century, we have to aim at achieving sustainable, environmentally friendly and cheap energy supply by employing renewable energy technologies associated with portable energy storage devices. Lithium-ion batteries can repeatedly generate clean energy from stored materials and convert reversely electric into chemical energy. The performance of lithium-ion batteries depends intimately on the properties of their materials. Presently used battery electrodes are expensive to be produced; they offer limited energy storage possibility and are unsafe to be used in larger dimensions restraining the diversity of application, especially in hybrid electric vehicles (HEVs) and electric vehicles (EVs). This thesis presents a major progress in the development of LiFePO4 as a cathode material for lithium-ion batteries. Using simple procedure, a completely novel morphology has been synthesized (mesocrystals of LiFePO4) and excellent electrochemical behavior was recorded (nanostructured LiFePO4). The newly developed reactions for synthesis of LiFePO4 are single-step processes and are taking place in an autoclave at significantly lower temperature (200 deg. C) compared to the conventional solid-state method (multi-step and up to 800 deg. C). The use of inexpensive environmentally benign precursors offers a green manufacturing approach for a large scale production. These newly developed experimental procedures can also be extended to other phospho-olivine materials, such as LiCoPO4 and LiMnPO4. The material with the best electrochemical behavior (nanostructured LiFePO4 with carbon coating) was able to deliver a stable 94% of the theoretically known capacity.

  20. Electrochemical reaction of lithium with orthorhombic bismuth tungstate thin films fabricated by radio-frequency sputtering

    International Nuclear Information System (INIS)

    Li Chilin; Sun Ke; Yu Le; Fu Zhengwen

    2009-01-01

    Bi 2 WO 6 thin films with fast deposition rate have been fabricated by radio-frequency (R.F.) sputtering deposition, and are used as positive electrodes in rechargeable thin film lithium batteries. An initial discharge capacity of 113 μAh/cm 2 -μm is obtainable for Bi 2 WO 6 film electrode with good capacity reversibility. A multiple-center reactive mechanism associated with both Bi 3+ /Bi 0 and W 6+ /W x+ (x 2 WO 6 electrochemical performance with those of Bi 2 O 3 and WO 3 thin films. A possible explanation about smooth capacity loss of Bi 2 WO 6 after long-term cycling is suggested from the incomplete reaction of Bi component. The advantages of Bi 2 WO 6 thin films over the singer-center Bi 2 O 3 or WO 3 thin films are shown in both the aspects of volumetric capacity and cycling life.

  1. Unique effect of mechanical crushing on the electrochemical intercalation of lithium in carbons of different morphologies; Effet unique du broyage mecanique sur l`intercalation electrochimique du lithium dans des carbones de morphologies differentes

    Energy Technology Data Exchange (ETDEWEB)

    Salver-Disma, F.; Tarascon, J.M. [Universite de Picardie, 80 - Amiens (France)

    1996-12-31

    Lithium ion batteries use an oxide as a positive electrode and a carbon material as a negative electrode. The performances of carbon electrodes have rapidly evolved during the last years thanks to the substitution of soft carbons of Conoco or MCMB-2510 type by graphites (F-399, MCMB-2528) and then by hard carbons. These high capacity carbons (700 mAh/g) have higher service life and volume capacity than graphites but their irreversible losses are greater (>20%). In this work, materials with similar electrochemical performances are prepared by mechanical crushing. Mechanical crushing allows to obtain a wide range of carbon materials with various morphologies, specific surfaces and levels of disorder. The formation of the passivation film is directly linked with the surface of materials. A reaction scheme of the reversible and irreversible capacities has been defined and has permitted to obtain compounds with reversible capacities of 720 mAh/g (2 lithium for 6 carbon). (J.S.)

  2. Unique effect of mechanical crushing on the electrochemical intercalation of lithium in carbons of different morphologies; Effet unique du broyage mecanique sur l`intercalation electrochimique du lithium dans des carbones de morphologies differentes

    Energy Technology Data Exchange (ETDEWEB)

    Salver-Disma, F; Tarascon, J M [Universite de Picardie, 80 - Amiens (France)

    1997-12-31

    Lithium ion batteries use an oxide as a positive electrode and a carbon material as a negative electrode. The performances of carbon electrodes have rapidly evolved during the last years thanks to the substitution of soft carbons of Conoco or MCMB-2510 type by graphites (F-399, MCMB-2528) and then by hard carbons. These high capacity carbons (700 mAh/g) have higher service life and volume capacity than graphites but their irreversible losses are greater (>20%). In this work, materials with similar electrochemical performances are prepared by mechanical crushing. Mechanical crushing allows to obtain a wide range of carbon materials with various morphologies, specific surfaces and levels of disorder. The formation of the passivation film is directly linked with the surface of materials. A reaction scheme of the reversible and irreversible capacities has been defined and has permitted to obtain compounds with reversible capacities of 720 mAh/g (2 lithium for 6 carbon). (J.S.)

  3. A soft chemical route to multicomponent lithium transition metal oxide nanowires as promising cathode materials for lithium secondary batteries

    International Nuclear Information System (INIS)

    Park, Dae-Hoon; Lim, Seung-Tae; Hwang, Seong-Ju

    2006-01-01

    We have synthesized 1D nanowires of lithium nickel manganese oxides with two different crystal structures through the chemical oxidation reaction of solid-state precursor LiMn 0.5 Ni 0.5 O 2 under hydrothermal condition. According to X-ray diffraction and elemental analyses, the nanowires obtained by persulfate treatments at 65 and 120 deg. C crystallize with a hexagonal layered and an α-MnO 2 -type structure, respectively, in which nickel and manganese ions exist in octahedral sites. Electron microscopic analyses reveal that the platelike crystallites of the precursor are changed into nanowires with the diameter of ∼20 nm after the persulfate treatment. Thermal and infrared spectroscopic analyses clearly demonstrate that, in comparison with α-MnO 2 -structured nanowires, the hexagonal layered nanowires contain less water molecules in the lattice, which makes them suitable for the application as electrode materials for lithium secondary batteries. According to electrochemical measurements, the hexagonal layered nanowires show a larger discharge capacity and an excellent cyclability with respect to repeated Li intercalation-disintercalation process. X-ray diffraction and electron microscopic analyses on the samples subjected to electrochemical analysis reveal that the layered structure and 1D morphology of the nanowires are still maintained after the electrochemical cyclings, which is responsible for their excellent electrochemical performances

  4. Lithium and sodium batteries with polysulfide electrolyte

    KAUST Repository

    Li, Mengliu

    2017-12-28

    A battery comprising: at least one cathode, at least one anode, at least one battery separator, and at least one electrolyte disposed in the separator, wherein the anode is a lithium metal or lithium alloy anode or an anode adapted for intercalation of lithium ion, wherein the cathode comprises material adapted for reversible lithium extraction from and insertion into the cathode, and wherein the separator comprises at least one porous, electronically conductive layer and at least one insulating layer, and wherein the electrolyte comprises at least one polysulfide anion. The battery provides for high energy density and capacity. A redox species is introduced into the electrolyte which creates a hybrid battery. Sodium metal and sodium-ion batteries also provided.

  5. Lithium-Excess Research of Cathode Material Li2MnTiO4 for Lithium-Ion Batteries

    OpenAIRE

    Zhang, Xinyi; Yang, Le; Hao, Feng; Chen, Haosen; Yang, Meng; Fang, Daining

    2015-01-01

    Lithium-excess and nano-sized Li2+xMn1−x/2TiO4 (x = 0, 0.2, 0.4) cathode materials were synthesized via a sol-gel method. The X-ray diffraction (XRD) experiments indicate that the obtained main phases of Li2.0MnTiO4 and the lithium-excess materials are monoclinic and cubic, respectively. The scanning electron microscope (SEM) images show that the as-prepared particles are well distributed and the primary particles have an average size of about 20–30 nm. The further electrochemical tests revea...

  6. Electrochemical performance of a rechargeable lithium battery containing a Li Mn{sub 2} O{sub 4} cathode; Desempenho eletroquimico de uma bateria recarregavel de litio com catodo de LiMn{sub 2}O{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Amaral, Fabio A.; Ferracin, Luiz C.; Brazuna, Priscila R.; Bocchi, Nerilso [Sao Carlos Univ., SP (Brazil). Dept. de Quimica. Lab. de Pesquisas em Eletroquimica

    1999-07-01

    This paper reports the evaluation of a rechargeable lithium battery, containing a Li Mn{sub 2} O{sub 4} cathode obtained from the {epsilon}-Mn O{sub 2}, through measurements of galvanostatic charge and discharge. The cathode presented a satisfactory electrochemical performance with charge capacity of approximately 110 m A h g{sup -1}. The Teflon electrochemical cell presented satisfactory results only for the initial charge and discharge cycles.

  7. Facile synthesis of ultrafine SnO{sub 2} nanoparticles on graphene nanosheets via thermal decomposition of tin-octoate as anode for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jinkai; Xie, Sanmu; Cao, Daxian; Lu, Xuan [Xi’an Jiaotong University, State Key Lab of Electrical Insulation and Power Equipment, Center of Nanomaterials for Renewable Energy (CNRE), School of Electrical Engineering (China); Meng, Lingjie, E-mail: menglingjie@mail.xjtu.edu.cn [Xi’an Jiaotong University, Department of Chemistry, School of Science (China); Yang, Guidong [Xi’an Jiaotong University, Department of Chemical Engineering, School of Chemical Engineering and Technology (China); Wang, Hongkang, E-mail: hongkang.wang@mail.xjtu.edu.cn [Xi’an Jiaotong University, State Key Lab of Electrical Insulation and Power Equipment, Center of Nanomaterials for Renewable Energy (CNRE), School of Electrical Engineering (China)

    2016-09-15

    We demonstrate a facile synthesis of ultrafine SnO{sub 2} nanoparticles within graphene nanosheets (GNSs) via thermal decomposition of tin-octoate, in which tin-octoate is firstly blended with GNSs followed by annealing in air at a low temperature (350 °C) and a short time (1 h). As anode for lithium ion batteries, the SnO{sub 2}/GNSs displays superior cycle and rate performance, delivering reversible capacities of 803 and 682 mA h/g at current densities of 200 and 500 mA/g after 120 cycles, respectively, much higher than that of pure SnO{sub 2} and GNSs counterparts (143 and 310 mA h/g at 500 mA/g after 120 cycles, respectively). The enhanced electrochemical performance is attributed to the ultrafine SnO{sub 2} nanoparticle size and introduction of GNSs. GNSs prevent the aggregation of the ultrafine SnO{sub 2} nanoparticles, which alleviate the stress and also provide more electrochemically active sites for lithium insertion and extraction. Moreover, GNSs with large specific surface area (~363 m{sup 2}/g) act as a good electrical conductor which greatly improves the electrode conductivity and also an excellent buffer matrix to tolerate the severe volume changes originated from the Li-Sn alloying-dealloying. This work provides a straight-forward synthetic approach for the design of novel composite anode materials with superior electrochemical performance.

  8. NASICON Open Framework Structured Transition Metal Oxides for Lithium Batteries

    OpenAIRE

    Begam, K.M.; Michael, M.S.; Prabaharan, S.R.S.

    2010-01-01

    We identified a group of NASICON open framework structured polyanion materials and examined the materials for rechargeable lithium battery application. We found that the open framework structure of these materials facilitated easy insertion/extraction of lithium into/from their structure. We synthesized the materials in lithium-rich [Li2M2(MoO4)3] and lithium-free [LixM2(MoO4)3] (M= Ni, Co) phases, for the first time, by means of a low temperature soft-combustion technique. The soft-combustio...

  9. Mechanics of high-capacity electrodes in lithium-ion batteries

    International Nuclear Information System (INIS)

    Zhu, Ting

    2016-01-01

    Rechargeable batteries, such as lithium-ion batteries, play an important role in the emerging sustainable energy landscape. Mechanical degradation and resulting capacity fade in high-capacity electrode materials critically hinder their use in high-performance lithium-ion batteries. This paper presents an overview of recent advances in understanding the electrochemically-induced mechanical behavior of the electrode materials in lithium-ion batteries. Particular emphasis is placed on stress generation and facture in high-capacity anode materials such as silicon. Finally, we identify several important unresolved issues for future research. (topical review)

  10. A transfer function type of simplified electrochemical model with modified boundary conditions and Padé approximation for Li-ion battery: Part 1. lithium concentration estimation

    Science.gov (United States)

    Yuan, Shifei; Jiang, Lei; Yin, Chengliang; Wu, Hongjie; Zhang, Xi

    2017-06-01

    To guarantee the safety, high efficiency and long lifetime for lithium-ion battery, an advanced battery management system requires a physics-meaningful yet computationally efficient battery model. The pseudo-two dimensional (P2D) electrochemical model can provide physical information about the lithium concentration and potential distributions across the cell dimension. However, the extensive computation burden caused by the temporal and spatial discretization limits its real-time application. In this research, we propose a new simplified electrochemical model (SEM) by modifying the boundary conditions for electrolyte diffusion equations, which significantly facilitates the analytical solving process. Then to obtain a reduced order transfer function, the Padé approximation method is adopted to simplify the derived transcendental impedance solution. The proposed model with the reduced order transfer function can be briefly computable and preserve physical meanings through the presence of parameters such as the solid/electrolyte diffusion coefficients (Ds&De) and particle radius. The simulation illustrates that the proposed simplified model maintains high accuracy for electrolyte phase concentration (Ce) predictions, saying 0.8% and 0.24% modeling error respectively, when compared to the rigorous model under 1C-rate pulse charge/discharge and urban dynamometer driving schedule (UDDS) profiles. Meanwhile, this simplified model yields significantly reduced computational burden, which benefits its real-time application.

  11. Influence of surfactants on the microstructure and electrochemical performance of the tin oxide anode in lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yan-Hui, E-mail: sunyanhui0102@163.com [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Guangzhou Key Laboratory of Materials for Energy Conversion and Storage, South China Normal University, Guangzhou 510006 (China); Dong, Pei-Pei; Liu, Shan; Nan, Jun-Min [School of Chemistry and Environment, South China Normal University, Guangzhou 510006 (China); Guangzhou Key Laboratory of Materials for Energy Conversion and Storage, South China Normal University, Guangzhou 510006 (China)

    2016-02-15

    Highlights: • CTAB and SDS alter the formation of SnO{sub 2} from nanosheets to nanocubes during oxalate precipitation. • The CTAB concentration affects the SnO{sub 2} crystal growth direction, morphology and size. • The SnO{sub 2} anode synthesized using CTAB exhibited superior electrochemical performance. • Proposed a mechanism of influence of surfactant on SnO{sub 2} in the precipitation and annealing process. - Abstract: Different SnO{sub 2} micro–nano structures are prepared by precipitation using a surfactant-assisted process. The surfactants, such as cetyltriethylammonium bromide (CTAB) or sodium dodecyl benzene sulfonate (SDBS), can change the crystal growth direction and microstructure of SnO{sub 2} primary and secondary particles. Larger SnO{sub 2} nanosheets were synthesized without surfactant, and micro-fragments composed of small nanospheres or nanocubes were synthesized using CTAB and SDBS. The CTAB-assisted process resulted in smaller primary particles and larger specific surface area and larger pore volume, as a lithium-ion-battery anode that exhibits superior electrochemical performance compared to the other two anodes. Further investigation showed that the concentration of CTAB had a substantial influence on the growth of the crystal face, morphology and size of the SnO{sub 2} secondary particles, which influenced the electrochemical performance of the anode. A simple mechanism for the influence of surfactants on SnO{sub 2} morphology and size in the precipitation and annealing process is proposed.

  12. Integrated Interface Strategy toward Room Temperature Solid-State Lithium Batteries.

    Science.gov (United States)

    Ju, Jiangwei; Wang, Yantao; Chen, Bingbing; Ma, Jun; Dong, Shanmu; Chai, Jingchao; Qu, Hongtao; Cui, Longfei; Wu, Xiuxiu; Cui, Guanglei

    2018-04-25

    Solid-state lithium batteries have drawn wide attention to address the safety issues of power batteries. However, the development of solid-state lithium batteries is substantially limited by the poor electrochemical performances originating from the rigid interface between solid electrodes and solid-state electrolytes. In this work, a composite of poly(vinyl carbonate) and Li 10 SnP 2 S 12 solid-state electrolyte is fabricated successfully via in situ polymerization to improve the rigid interface issues. The composite electrolyte presents a considerable room temperature conductivity of 0.2 mS cm -1 , an electrochemical window exceeding 4.5 V, and a Li + transport number of 0.6. It is demonstrated that solid-state lithium metal battery of LiFe 0.2 Mn 0.8 PO 4 (LFMP)/composite electrolyte/Li can deliver a high capacity of 130 mA h g -1 with considerable capacity retention of 88% and Coulombic efficiency of exceeding 99% after 140 cycles at the rate of 0.5 C at room temperature. The superior electrochemical performance can be ascribed to the good compatibility of the composite electrolyte with Li metal and the integrated compatible interface between solid electrodes and the composite electrolyte engineered by in situ polymerization, which leads to a significant interfacial impedance decrease from 1292 to 213 Ω cm 2 in solid-state Li-Li symmetrical cells. This work provides vital reference for improving the interface compatibility for room temperature solid-state lithium batteries.

  13. Reliable reference electrodes for lithium-ion batteries

    KAUST Repository

    La Mantia, F.

    2013-06-01

    Despite the high attention drawn to the lithium-ion batteries by the scientific and industrial community, most of the electrochemical characterization is carried out using poor reference electrodes or even no reference electrode. In this case, the performances of the active material are inaccurate, especially at high current densities. In this work we show the error committed in neglecting the polarizability of lithium counter electrodes, and we propose two reference electrodes to use in organic electrolytes based on lithium salts, namely Li4Ti5O12 and LiFePO 4. In particular, it was observed that, the polarizability of the metallic lithium counter electrode has a relevant stochastic component, which renders measurements at high current densities (above 1 mA·cm - 2) in two electrode cells non reproducible.

  14. Nanostructure Sn-Co-C composite lithium ion battery electrode with unique stability and high electrochemical performance

    International Nuclear Information System (INIS)

    Li Mengyuan; Liu Chunling; Shi Meirong; Dong Wensheng

    2011-01-01

    Nanostructure Sn-Co-C composites with different compositions are synthesized by a simple solution polymerization using inexpensive raw materials followed by pyrolysis in nitrogen atmosphere. The nanostructure Sn-Co-C composites are characterized using various analytic techniques. The results show that the electrochemical performances of the composites are strongly dependent on their structure and composition. Among these composites the Sn-Co-C-1 with a weight composition of Sn 0.31 Co 0.09 C 0.6 exhibits high reversible capacity and excellent cycleability when used as an anode for rechargeable lithium ion batteries. This composite is composed of SnCo 2 , SnCo, Sn and amorphous carbon, and the nanoparticles of SnCo 2 , SnCo and Sn are uniformly dispersed into the amorphous carbon matrix, the average diameter of these metal nanoparticles is 8.44 nm.

  15. Significant improvement of electrochemical performance of Cu ...

    Indian Academy of Sciences (India)

    LiVPO4F cathode material for lithium-ion batteries. YU ZHANGa,∗, XIAOLAN BAIb ... and energy dispersive spectroscopy (EDS). ... Analysis of electrochemical impedance spectra (EIS) ... studied with a SEM (JSM-7500F, Japan) equipped with.

  16. Enhanced Cyclability of Lithium-Oxygen Batteries with Electrodes Protected by Surface Films Induced via In-Situ Electrochemical Process

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Bin; Xu, Wu; Tao, Jinhui; Yan, Pengfei; Zheng, Jianming; Engelhard, Mark H.; Lu, Dongping; Wang, Chongmin; Zhang, Jiguang

    2018-04-16

    Although the rechargeable lithium-oxygen (Li-O2) batteries have extremely high theoretical specific energy, the practical application of these batteries is still limited by the instability of their carbon-based air-electrode, Li metal anode, and electrolytes towards reduced oxygen species. Here we demonstrate a simple one-step in-situ electrochemical pre-charging strategy to generate thin protective films on both carbon nanotubes (CNTs) air-electrode and Li metal anode simultaneously under an inert atmosphere. Li-O2 cells after such pre-treatment demonstrate significantly extended cycle life of 110 and 180 cycles under the capacity-limited protocol of 1000 mAh g-1 and 500 mAh g-1, respectively, which is far more than those without pre-treatment. The thin-films formed from decomposition of electrolyte during in-situ electrochemical pre-charging process in an inert environment can protect both CNTs air-electrode and Li metal anode prior to conventional Li-O2 discharge/charge cycling where reactive reduced oxygen species are formed. This work provides a new approach for protections of carbon-based air-electrode and Li metal anode in practical Li-O2 batteries, and may also be applied to other battery systems.

  17. Preparation of 3D flower-like NiO hierarchical architectures and their electrochemical properties in lithium-ion batteries

    International Nuclear Information System (INIS)

    Li, Qing; Chen, Yuejiao; Yang, Ting; Lei, Danni; Zhang, Guanhua; Mei, Lin; Chen, Libao; Li, Qiuhong; Wang, Taihong

    2013-01-01

    3D flower-like NiO hierarchical architectures have been synthesized by a simple ethanolamine (EA)-mediated self-assembly route and subsequent calcination process. The synthesized β-Ni(OH) 2 precursors annealed at 300, 400 and 500 °C exhibit similar morphology by scanning electron microscopy and different crystallinity, surface area, and pore distribution via X-ray diffraction, Fourier transform infrared spectroscopy and nitrogen adsorption/desorption isotherms. The electrochemical properties indicate that the synthesized NiO hierarchical architectures annealed at 300 °C show the best electrochemical performance, which presents a reversible specific capacity of 713 mAh g −1 at a current density of 100 mA g −1 after 40 cycles. With varying the rate from 100 to 1000 mA g −1 , the capacity still remains 580 mAh g −1 at 500 mA g −1 after 18 cycles and resumes to 470 mAh g −1 at the same rate after 30 cycles. The above results indicate that the 3D flower-like NiO hierarchical architectures are promising anode materials for lithium ion batteries

  18. Electrochemical properties of quaternary ammonium salts for electrochemical capacitors

    Energy Technology Data Exchange (ETDEWEB)

    Ue, Makoto; Takeda, Masayuki; Takehara, Masahiro; Mori, Shoichiro [Mitsubishi Chemical Corp., Inashiki, Ibaraki (Japan). Tsukuba Research Center

    1997-08-01

    The limiting reduction and oxidation potentials and electrolytic conductivities of new quaternary ammonium salts were examined for electrochemical capacitor applications, whose anions have already been tested as lithium salts for lithium battery applications. The anodic stability was in the following order BR{sub 4}{sup {minus}} < ClO{sub 4}{sup {minus}} {le} CF{sub 3}SO{sub 3}{sup {minus}} < (CF{sub 3}SO{sub 2}){sub 2}N{sup {minus}} {le} C{sub 4}F{sub 9}SO{sub 3}{sup {minus}} < BF{sub 4}{sup {minus}} < PF{sub 6}{sup {minus}} {le} AsF{sub 6}{sup {minus}} < SbF{sub 6}{sup {minus}}. The electrolytic conductivities of Me{sub 4{minus}n}Et{sub n}N(CF{sub 3}SO{sub 2}){sub 2}N (n = 0--4) were examined in comparison with Me{sub 4{minus}n}Et{sub n}NBF{sub 4} counterparts. These imide salts showed good solubility, relatively high conductivity, and anodic stability in propylene carbonate. Et{sub 4}N(CF{sub 3}SO{sub 2}){sub 2}N was found to be a good supporting salt for low permittivity organic solvents, and it afforded a highly conductive electrolyte system based on the ethylene carbonate-dimethyl carbonate mixed solvent, which is useful for electrochemical capacitor applications.

  19. Microstructure study of electrochemically driven Li{sub x}Si

    Energy Technology Data Exchange (ETDEWEB)

    Son, Seoung-Bum [Department of Materials Science and Engineering, Seoul National University, Seoul, 151-742 (Korea, Republic of); Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO, 80309 (United States); Trevey, James E.; Dunn, Martin L.; Lee, Se-Hee [Department of Mechanical Engineering, University of Colorado at Boulder, Boulder, CO, 80309 (United States); Roh, Hyunchul; Kim, Sung-Hwan; Han, Heung Nam; Oh, Kyu Hwan [Department of Materials Science and Engineering, Seoul National University, Seoul, 151-742 (Korea, Republic of); Kim, Kee-Bum [Department of Materials Science and Engineering, Seoul National University, Seoul, 151-742 (Korea, Republic of); High Temperature Energy Materials Research Center, Korea Institute of Science and Technology, Seoul, 136-791 (Korea, Republic of); Cho, Jong Soo [Department of Materials Science and Engineering, Seoul National University, Seoul, 151-742 (Korea, Republic of); MK Electron, 316-2 Geumeo-ri, Pogok-myeon, Yongin-si, Gyeong gi-do, 449-810 (Korea, Republic of); Moon, Jeong-Tak [MK Electron, 316-2 Geumeo-ri, Pogok-myeon, Yongin-si, Gyeong gi-do, 449-810 (Korea, Republic of); DeLuca, Christopher M.; Maute, Kurt K. [Department of Aerospace Engineering Sciences, University of Colorado, CB 429, Boulder, CO, 80301-0429 (United States)

    2011-11-15

    We report the direct observation of microstructural changes of Li{sub x}Si electrode with lithium insertion. HRTEM experiments confirm that lithiated amorphous silicon forms a shell around a core made up of the unlithiated silicon and that fully lithiated silicon contains a large number of pores of which concentration increases toward the center of the particle. Chemomechanical modeling is employed in order to explain this mechanical degradation resulting from stresses in the Li{sub x}Si particles with lithium insertion. Because lithiation-induced volume expansion and pulverization are the key mechanical effects that plague the performance and lifetime of high-capacity Si anodes in lithium-ion batteries, our observations and chemomechanical simulation provide important mechanistic insight for the design of advanced battery materials. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Facile synthesis and electrochemical properties of continuous porous spheres assembled from defect-rich, interlayer-expanded, and few-layered MoS2/C nanosheets for reversible lithium storage

    Science.gov (United States)

    Chen, Biao; Lu, Huihui; Zhao, Naiqin; Shi, Chunsheng; Liu, Enzuo; He, Chunnian; Ma, Liying

    2018-05-01

    Hollow or continuous porous hierarchical MoS2/C structures with large Li-ion and electron transport kinetics, and high structural stability are urgent needs for their application in lithium ion batteries. In this regard, a novel continuous porous micro-sphere constructed from defect-rich, interlayer-expanded, and few-layered MoS2/C nanosheets is successfully synthesized through a facile one-pot hydrothermal method. The polyvinyl pyrrolidone surfactant serves as carbon source and supporter, while the CS2 works as soft template and sulfur source during hydrothermal process. The morphologies, structures, and electrochemical properties are systematically characterized. Importantly, it should be noted that the unique porous micro-spheres with merits of rich-defect, expanded-interlayer, few-layer (integrating carbon are favorable for lithium ion batteries application. When the uniform composites are used as lithium ion batteries anode materials, they deliver a high reversible capacity, excellent cycling performance (average capacity fading of 0.037% per cycle at 0.2 A g-1), and good rate capability.

  1. Electrochemically induced nuclear fusion of deuterium

    International Nuclear Information System (INIS)

    Jorne, J.

    1990-01-01

    In this paper cold fusion of deuterium by electrolysis of heavy water onto a palladium (or titanium) cathode is reported. Contrary to the assumption of Fleishmann and Pons that electrochemically compressed D + exists inside the palladium cathode, the observations of Jones et al. can be partially explained by the simultaneous presence of deuteride D - and the highly mobile positive deuterium ion D + . The opposite charges reduce the intranuclear distance and enhance the tunneling fusion rate. Furthermore, alloying of lithium with palladium can stabilize a negatively charged deuteride ion due to the salinelike character of lithium deuteride. The enormous pressure (or fugacity), achieved by the applied electrochemical potential (10 30 atm), is a virtual pressure that would have existed in equilibrium with palladium deuteride (PdD x ). It is speculated that nuclear fusion occurs at the surface, and the PdD x serves as a reservoir for the supply of deuteride ions

  2. WS_2-Super P nanocomposites anode material with enhanced cycling stability for lithium ion batteries

    International Nuclear Information System (INIS)

    Huang, Jianfeng; Wang, Xin; Li, Jiayin; Cao, Liyun; Xu, Zhanwei; Wei, Hao

    2016-01-01

    WS_2-Super P nanocomposites are prepared for lithium battery anodes by a simple two-step process consisting of hydrothermal and sulfide reduction reactions. The addition of Super P (50 nm) as a conductive addictive is beneficial for decreasing the size of nanocomposites and improving their dispersibility, which could accelerate the insertion/extraction reaction between WS_2-Super P nanocomposite electrode and electrolyte. Compared to the pure WS_2, the WS_2-Super P nanocomposites exhibit highly improved electrochemical performance with initial discharge capacity of 421 mAh g"−"1, high initial Coulombic efficiency (81%), low charge transfer impedance (53 Ω) and good retentive capacity of 389 mAh g"−"1 after 200th cycles. The much improved electrochemical performance can be attributed to the incorporation of Super P, which facilitates the interface charge transfer and Li"+ diffusion. - Graphical abstract: The addition of Super P (50 nm) is beneficial for decreasing the size of WS_2-Super P nanocomposites, improving their dispersibility, accelerating the Li"+ transportation and the insertion/extraction reaction. The WS_2-Super P nanocomposites show higher cycling stability and rate performances than pure WS_2. - Highlights: • WS_2-Super P nanocomposites are prepared for LIBs anodes with good performances. • Super P as a conductive addictive is added into the WS_2 nanosheets. • The incorporation of Super P is beneficial for decreasing the size of composites. • Super P were embedded in WS_2 nanosheets for improving their dispersibility.

  3. Roles of surface chemistry on safety and electrochemistry in lithium ion batteries.

    Science.gov (United States)

    Lee, Kyu Tae; Jeong, Sookyung; Cho, Jaephil

    2013-05-21

    Motivated by new applications including electric vehicles and the smart grid, interest in advanced lithium ion batteries has increased significantly over the past decade. Therefore, research in this field has intensified to produce safer devices with better electrochemical performance. Most research has focused on the development of new electrode materials through the optimization of bulk properties such as crystal structure, ionic diffusivity, and electric conductivity. More recently, researchers have also considered the surface properties of electrodes as critical factors for optimizing performance. In particular, the electrolyte decomposition at the electrode surface relates to both a lithium ion battery's electrochemical performance and safety. In this Account, we give an overview of the major developments in the area of surface chemistry for lithium ion batteries. These ideas will provide the basis for the design of advanced electrode materials. Initially, we present a brief background to lithium ion batteries such as major chemical components and reactions that occur in lithium ion batteries. Then, we highlight the role of surface chemistry in the safety of lithium ion batteries. We examine the thermal stability of cathode materials: For example, we discuss the oxygen generation from cathode materials and describe how cells can swell and heat up in response to specific conditions. We also demonstrate how coating the surfaces of electrodes can improve safety. The surface chemistry can also affect the electrochemistry of lithium ion batteries. The surface coating strategy improved the energy density and cycle performance for layered LiCoO2, xLi2MnO3·(1 - x)LiMO2 (M = Mn, Ni, Co, and their combinations), and LiMn2O4 spinel materials, and we describe a working mechanism for these enhancements. Although coating the surfaces of cathodes with inorganic materials such as metal oxides and phosphates improves the electrochemical performance and safety properties of

  4. Novel synthesis of holey reduced graphene oxide (HRGO) by microwave irradiation method for anode in lithium-ion batteries

    Science.gov (United States)

    Alsharaeh, Edreese; Ahmed, Faheem; Aldawsari, Yazeed; Khasawneh, Majdi; Abuhimd, Hatem; Alshahrani, Mohammad

    2016-07-01

    In this work, holey reduced graphene oxide (HRGO) was synthesized by the deposition of silver (Ag) nanoparticles onto the reduced graphene oxide (RGO) sheets followed by nitric acid treatment to remove Ag nanoparticles by microwave irradiation to form a porous structure. The HRGO were characterized by X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), ultra violet-visible spectroscopy (UV-Vis), thermogravimetric analysis (TGA), and Raman spectroscopy. These novel HRGO exhibited high rate capability with excellent cycling stability as an anode material for lithium-ion batteries. The results have shown an excellent electrochemical response in terms of charge/discharge capacity (423 mAh/g at 100 mA/g). The cyclic performance was also exceptional as a high reversible capacity (400 mAh/g at 100 mA/g) was retained for 100 charge/discharge cycles. This fascinating electrochemical performance can be ascribed to their specific porous structure (2-5 nm pores) and high surface area (457 m2/g), providing numerous active sites for Li+ insertion, high electrical conductivity, low charge-transfer resistance across the electrolyte-electrode interface, and improved structural stability against the local volume change during Li+ insertion-extraction. Such electrodes are envisioned to be mass scalable with relatively simple and low-cost fabrication procedures, thereby providing a clear pathway toward commercialization.

  5. High-Rate Long-Life Pored Nanoribbon VNb9O25 Built by Interconnected Ultrafine Nanoparticles as Anode for Lithium-Ion Batteries.

    Science.gov (United States)

    Qian, Shangshu; Yu, Haoxiang; Yan, Lei; Zhu, Haojie; Cheng, Xing; Xie, Ying; Long, Nengbing; Shui, Miao; Shu, Jie

    2017-09-13

    VNb 9 O 25 is a novel lithium storage material, which has not been systematically investigated so far. Via electrospinning technology, VNb 9 O 25 samples with two different morphologies, pored nanoribbon and rodlike nanoparticles, are prepared in relatively low temperature and time-saving calcination conditions. It is found that the formation process of different morphologies depends on the control of self-aggregation of the precursor by using different sample collectors. Compared with rodlike VNb 9 O 25 (RL-VNb 9 O 25 ), pored nanoribbon VNb 9 O 25 (PR-VNb 9 O 25 ) can deliver a higher specific capacity, lower capacity loss, and better cyclability. Even cycled at 1000 mA g -1 , the reversible capacity of 132.3 mAh g -1 is maintained by PR-VNb 9 O 25 after 500 cycles, whereas RL-VNb 9 O 25 only exhibits a capacity of 102.7 mAh g -1 . The enhancement should be attributed to the pored nanoribbon structure with large specific surface area and shorter pathway for lithium ions transport. Furthermore, the lithium ions insertion/extraction process is verified from refinement results of in situ X-ray diffraction data, which is associated with a lithium occupation process in type III and VI cavities through tunnels I, II, and III. In addition, high structural stability and electrochemical reversibility are also demonstrated. All of these advantages suggest that PR-VNb 9 O 25 is a promising anode material for lithium-ion batteries.

  6. Measurement of lithium ion transference numbers of electrolytes for lithium-ion batteries. A comparative study with five various methods.; Messung von Lithium-Ionen Ueberfuehrungszahlen an Elektrolyten fuer Lithium-Ionen Batterien. Eine vergleichende Studie mit fuenf verschiedenen Methoden

    Energy Technology Data Exchange (ETDEWEB)

    Zugmann, Sandra

    2011-03-30

    Transference numbers are decisive transport properties to characterize electrolytes. They state the fraction of a certain species at charge transport and are defined by the ratio of current Ii that is transported by the ionic species i to the total current I. They are very important for lithium-ion batteries, because they give information about the real lithium transport and the efficiency of the battery. If the transference number has a too small value, for example, the lithium cannot be ''delivered'' fast enough in the discharge process. This can lead to precipitation of the salt at the anode and to depletion of the electrolyte at the cathode. Currently only a few adequate measurement methods for non-aqueous lithium electrolytes exist. The aim of this work was the installation of measurement devices and the comparison of different methods of transference numbers for electrolytes in lithium-ion batteries. The advantages and disadvantages for every method should be analyzed and transference numbers of new electrolyte be measured. In this work a detailed comparison of different methods with electrochemical and spectroscopic factors was presented for the first time. The galvanostatic polarization, the potentiostatic polarization, the emf method, the determination by NMR and the determination by conductivity measurements were tested for their practical application and used for different lithium salts in several solvents. The results show clearly that the assumptions made for every method affect the measured transference number a lot. They can have different values depending on the used method and the concentration dependence can even have contrary tendencies for methods with electrochemical or spectroscopic aspects. The influence of ion pairs is the determining factor at the measurements. For a full characterization of electrolytes a complete set of transport parameters is necessary, including diffusion coefficients, conductivity, transference number and ideally

  7. Measurement of lithium ion transference numbers of electrolytes for lithium-ion batteries. A comparative study with five various methods.; Messung von Lithium-Ionen Ueberfuehrungszahlen an Elektrolyten fuer Lithium-Ionen Batterien. Eine vergleichende Studie mit fuenf verschiedenen Methoden

    Energy Technology Data Exchange (ETDEWEB)

    Zugmann, Sandra

    2011-03-30

    Transference numbers are decisive transport properties to characterize electrolytes. They state the fraction of a certain species at charge transport and are defined by the ratio of current Ii that is transported by the ionic species i to the total current I. They are very important for lithium-ion batteries, because they give information about the real lithium transport and the efficiency of the battery. If the transference number has a too small value, for example, the lithium cannot be ''delivered'' fast enough in the discharge process. This can lead to precipitation of the salt at the anode and to depletion of the electrolyte at the cathode. Currently only a few adequate measurement methods for non-aqueous lithium electrolytes exist. The aim of this work was the installation of measurement devices and the comparison of different methods of transference numbers for electrolytes in lithium-ion batteries. The advantages and disadvantages for every method should be analyzed and transference numbers of new electrolyte be measured. In this work a detailed comparison of different methods with electrochemical and spectroscopic factors was presented for the first time. The galvanostatic polarization, the potentiostatic polarization, the emf method, the determination by NMR and the determination by conductivity measurements were tested for their practical application and used for different lithium salts in several solvents. The results show clearly that the assumptions made for every method affect the measured transference number a lot. They can have different values depending on the used method and the concentration dependence can even have contrary tendencies for methods with electrochemical or spectroscopic aspects. The influence of ion pairs is the determining factor at the measurements. For a full characterization of electrolytes a complete set of transport parameters is necessary, including diffusion coefficients, conductivity, transference

  8. Comparative Issues of Cathode Materials for Li-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Christian M. Julien

    2014-03-01

    Full Text Available After an introduction to lithium insertion compounds and the principles of Li-ion cells, we present a comparative study of the physical and electrochemical properties of positive electrodes used in lithium-ion batteries (LIBs. Electrode materials include three different classes of lattices according to the dimensionality of the Li+ ion motion in them: olivine, layered transition-metal oxides and spinel frameworks. Their advantages and disadvantages are compared with emphasis on synthesis difficulties, electrochemical stability, faradaic performance and security issues.

  9. Electrochemical properties of SnO2/carbon composite materials as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Wang Jie; Zhao Hailei; Liu Xiaotong; Wang Jing; Wang Chunmei

    2011-01-01

    Highlights: → SnO 2 /carbon powders with a cauliflower-like particle structure were synthesized. → Post-annealing can improve the electrochemical properties of SnO 2 /C composite. → The 500 deg. C-annealed SnO 2 /C shows the best electrochemical performance. → The lithium ion diffusion coefficients of the SnO 2 /C electrodes were calculated. - Abstract: SnO 2 /carbon composite anode materials were synthesized from SnCl 4 .5H 2 O and sucrose via a hydrothermal route and a post heat-treatment. The synthesized spherical SnO 2 /carbon powders show a cauliflower-like micro-sized structure. High annealing temperature results in partial reduction of SnO 2 . Metallic Sn starts to emerge at 500 deg. C. High Sn content in SnO 2 /carbon composite is favorable for the increase of initial coulombic efficiency but not for the cycling stability. The SnO 2 /carbon annealed at 500 deg. C exhibits high specific capacity (∼400 mAh g -1 ), stable cycling performance and good rate capability. The generation of Li 2 O in the first lithiation process can prevent the aggregation of active Sn, while the carbon component can buffer the big volume change caused by lithiation/delithiation of active Sn. Both of them make contribution to the better cycle stability.

  10. Hierarchical architecture of ReS{sub 2}/rGO composites with enhanced electrochemical properties for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Fei; Chen, Yuanfu, E-mail: yfchen@uestc.edu.cn; Zheng, Binjie; He, Jiarui; Li, Qian; Wang, Xinqiang; Lin, Jie; Zhou, Jinhao; Yu, Bo; Li, Pingjian; Zhang, Wanli

    2017-08-15

    Highlights: • The ReS{sub 2}/rGO composites have been synthesized by a facile one-pot method. • The ReS{sub 2}/rGO composites exhibit hierarchical architecture. • The ReS{sub 2}/rGO composites deliver better electrochemical performances than ReS{sub 2}. • The enhanced performance is due to porous and conductive structure of ReS{sub 2}/rGO. - Abstract: Rhenium disulfide (ReS{sub 2}), a two-dimensional (2D) semiconductor, has attracted more and more attention due to its unique anisotropic electronic, optical, mechanical properties. However, the facile synthesis and electrochemical property of ReS{sub 2} and its composite are still necessary to be researched. In this study, for the first time, the ReS{sub 2}/reduced graphene oxide (rGO) composites have been synthesized through a facile and one-pot hydrothermal method. The ReS{sub 2}/rGO composites exhibit a hierarchical, interconnected, and porous architecture constructed by nanosheets. As anode for lithium-ion batteries, the as-synthesized ReS{sub 2}/rGO composites deliver a large initial capacity of 918 mAh g{sup −1} at 0.2 C. In addition, the ReS{sub 2}/rGO composites exhibit much better electrochemical cycling stability and rate capability than that of bare ReS{sub 2}. The significant enhancement in electrochemical property can be attributed to its unique architecture constructed by nanosheets and porous structure, which can allow for easy electrolyte infiltration, efficient electron transfer, and ionic diffusion. Furthermore, the graphene with high electronic conductivity can provide good conductive passageways. The facile synthesis approach can be extended to prepare other 2D transition metal dichalcogenides semiconductors for energy storage and catalytic application.

  11. Quantitative detection of microscopic lithium distributions with neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Neri, Giulia; Gernhaeuser, Roman; Lichtinger, Josef; Winkler, Sonja; Seiler, Dominik; Bendel, Michael [Technische Universitaet Muenchen, Physik-Department (Germany); Kunze-Liebhaeuser, Julia; Brumbarov, Jassen; Portenkirchner, Engelbert [Institut fuer Physikalische Chemie, Leopold-Franzens-Universitaet Innsbruck (Austria); Renno, Axel; Rugel, Georg [Helmholtz Zentrum Dresden Rossendorf, Helmholtz-Institut Freiberg fuer Ressourcentechnologie (Germany)

    2016-07-01

    The importance of lithium in the modern industrial society is continuously increasing. Spatially resolved detection of tritium particles from {sup 6}Li(n,α){sup 3}H nuclear reactions is used to reconstruct microscopic lithium distributions. Samples are exposed to a flux of cold neutrons. Emitted charged particles are detected with a PSD. Introducing a pinhole aperture between target and detector, the experimental setup works like a ''camera obscura'', allowing to perform spatially resolved measurements. Tritium detection analysis was successfully used to reconstruct the lithium content in self-organized TiO{sub 2-x}-C and Si/TiO{sub 2-x}-C nanotubes electrochemically lithiated, for the first time. Titanium dioxide nanotubes are a candidate for a safe anode material in lithium-ion batteries. Also lithium distributions in geological samples, so called ''pathfinder-minerals'' containing lithium, like lepidolite from a pegmatite, were analyzed. With this development we present a new precision method using nuclear physics for material science.

  12. On the electrochemistry of tin oxide coated tin electrodes in lithium-ion batteries

    International Nuclear Information System (INIS)

    Böhme, Solveig; Edström, Kristina; Nyholm, Leif

    2015-01-01

    As tin based electrodes are of significant interest in the development of improved lithium-ion batteries it is important to understand the associated electrochemical reactions. In this work it is shown that the electrochemical behavior of SnO_2 coated tin electrodes can be described based on the SnO_2 and SnO conversion reactions, the lithium tin alloy formation and the oxidation of tin generating SnF_2. The CV, XPS and SEM data, obtained for electrodeposited tin crystals on gold substrates, demonstrates that the capacity loss often observed for SnO_2 is caused by the reformed SnO_2 layer serving as a passivating layer protecting the remaining tin. Capacities corresponding up to about 80 % of the initial SnO_2 capacity could, however, be obtained by cycling to 3.5 V vs. Li"+/Li. It is also shown that the oxidation of the lithium tin alloy is hindered by the rate of the diffusion of lithium through a layer of tin with increasing thickness and that the irreversible oxidation of tin to SnF_2 at potentials larger than 2.8 V vs. Li"+/Li is due to the fact that SnF_2 is formed below the SnO_2 layer. This improved electrochemical understanding of the SnO_2/Sn system should be valuable in the development of tin based electrodes for lithium-ion batteries.

  13. Numerical study on lithium titanate battery thermal response under adiabatic condition

    International Nuclear Information System (INIS)

    Sun, Qiujuan; Wang, Qingsong; Zhao, Xuejuan; Sun, Jinhua; Lin, Zijing

    2015-01-01

    Highlights: • The thermal behavior of lithium titanate battery during cycling was investigated. • The temperature rate in charging was less than that of discharging in the cycling. • The temperature difference was less than 0.02 °C at 0.5 C in adiabatic condition. • The temperature distribution and thermal runaway of the battery were predicted. - Abstract: To analyze the thermal behavior of 945 mA h lithium titanate battery during charging and discharging processes, the experimental and numerical studies are performed in this work. The cathode and anode of the 945 mA h lithium titanate soft package battery are the lithium nickel–cobalt–manganese-oxide and lithium titanate, respectively. In the experiment, an Accelerating Rate Calorimeter combined with battery cycler is employed to investigate the electrochemical–thermal behavior during charge–discharge cycling under the adiabatic condition. In numerical simulation, one electrochemical-thermal model is adopted to predict the thermal response and validated with the experimental results. From both experimental and simulated results, the profile of potential and current, the heat generation, the temperature, the temperature changing rate and the temperature distribution in the cell are obtained and thermal runaway is predicted. The analysis of the electrochemical and thermal behavior is beneficial for the commercial application of lithium titanate battery in the fields of electric vehicles and hybrid electric vehicles

  14. Materials for electrochemical capacitors

    Science.gov (United States)

    Simon, Patrice; Gogotsi, Yury

    2008-11-01

    Electrochemical capacitors, also called supercapacitors, store energy using either ion adsorption (electrochemical double layer capacitors) or fast surface redox reactions (pseudo-capacitors). They can complement or replace batteries in electrical energy storage and harvesting applications, when high power delivery or uptake is needed. A notable improvement in performance has been achieved through recent advances in understanding charge storage mechanisms and the development of advanced nanostructured materials. The discovery that ion desolvation occurs in pores smaller than the solvated ions has led to higher capacitance for electrochemical double layer capacitors using carbon electrodes with subnanometre pores, and opened the door to designing high-energy density devices using a variety of electrolytes. Combination of pseudo-capacitive nanomaterials, including oxides, nitrides and polymers, with the latest generation of nanostructured lithium electrodes has brought the energy density of electrochemical capacitors closer to that of batteries. The use of carbon nanotubes has further advanced micro-electrochemical capacitors, enabling flexible and adaptable devices to be made. Mathematical modelling and simulation will be the key to success in designing tomorrow's high-energy and high-power devices.

  15. Facile preparation and electrochemical characterization of poly (4-methoxytriphenylamine)-modified separator as a self-activated potential switch for lithium ion batteries

    International Nuclear Information System (INIS)

    Zhang, Haiyan; Cao, Yuliang; Yang, Hanxi; Lu, Shigang; Ai, Xinping

    2013-01-01

    Highlights: • A potential-sensitive separator is prepared by incorporating an electroactive poly (4-methoxytriphenylamine) (PMOTPA) into the micropores of a commercial porous polyolefin film. • This separator can be used as an internal and self-actuating voltage control device to provide overcharge protection for LiFePO 4 /Li 4 Ti 5 O 12 lithium ion batteries. • This type of the separators works reversibly and has no any discernable impact on the battery performances. -- Abstract: A potential-sensitive separator is prepared by incorporating an electroactive poly (4-methoxytriphenylamine) (PMOTPA) into the micropores of a commercial porous polyolefin film and tested as an internal voltage control device for overcharge protection of LiFePO 4 /Li 4 Ti 5 O 12 lithium ion batteries. The experimental results demonstrate that the PMOTPA polymer embedded in the separator can be electrochemically p-doped at overcharged voltages into an electrically conductive state, producing an internal conducting bypass for shunting the charge current to maintain the charge voltage of LiFePO 4 /Li 4 Ti 5 O 12 cells at a safety value less than 2.6 V, thus protecting the cell from voltage runaway. Since this type of the separators works reversibly and has no any discernable impact on the battery performances, it may offer a self-protection mechanism for development of safer lithium ion batteries

  16. First-principles studies of complex hydrides for lithium-ion battery and hydrogen storage applications

    Science.gov (United States)

    Mason, Timothy Hudson

    We employ density functional theory in a computational study of two energy storage systems. In the first, we explore the thermodynamic viability of light metal hydrides as a high capacity Li-ion battery negative electrode. Given a set of solid-state and gas-phase reactants, we have determined the phase diagram in the Li-Mg-B-N-H system in the grand canonical ensemble as a function of lithium electrochemical potential. We present computational results for several new conversion reactions with predicted capacities between 2400 and 4000 mAhg-1 that are thermodynamically favorable and that do not involve gas evolution. We provide experimental evidence for the reaction pathway on delithiation for the compound Li4BN3H10 and compare with our theoretical prediction. The maximum volume increase for these materials on lithium insertion is significantly smaller than that for Si, whose 400% expansion hinders its cyclability. In the second study, we attempt to gain understanding of recent experimental results of lithium borohydride nanoconfined in highly ordered nanoporous carbon. The carbon environment is modeled as a single sheet of graphene, and adsorption energies are calculated for nanoparticles of the constituent phases of LiBH 4 desorption processes (LiBH4, LiH, lithium and boron). We find good agreement with previous studies of a single lithium atom adsorbed onto graphene. We predict that infiltrated LiBH4 will decompose such that boron is trapped in carbon vacancies, and that the resulting boron doping is required to achieve negative wetting energies for the remaining LiBH4. Desorption enthalpies are found to increase with shrinking cluster sizes, suggesting that the observed lowering of desorption temperatures is a kinetic effect although interactions with the carbon surface itself are predicted to have an overall effect of decreasing the desorption enthalpy .

  17. “Double-Sandwich-Like” CuS@reduced graphene oxide as an Anode in Lithium Ion Batteries with Enhanced Electrochemical Performance

    International Nuclear Information System (INIS)

    Ren, Yurong; Wei, Hengma; Yang, Bo; Wang, Jiawei; Ding, Jianning

    2014-01-01

    Graphical abstract: CuS@reduced graphene oxide displays excellent electrochemical behavior as an anode material for Lithium ion batteries. - Abstract: The CuS@reduced graphene oxide (CSG) was synthesized and used as an anode material in lithium ion batteries (LIBs). CuS nanoparticles were homogeneously dispersed on the surfaces of reduced graphene oxide (rGO) nanosheets via a hydrothermal method. The rGO nanosheets in the CSG hydrids can improve the electrical conductivity and structure stability of CSG. The LIB with a CSG anode displays excellent performance, with a first discharge capacity up to 851 mAh/g, a reversible capacity of 648.1 mAh/g in the initial cycle, and an enhanced cyclic performance with a discharge capacity of 710.7 mAh/g at the 100 th cycle, which corresponds to 114.3% of the theoretical value of CSG and 83.5% of the first discharge capacity accompanied by an excellent Coulombic efficiency of 99.1% at a current density of 0.2 C, which is much larger than (close to 4.5 times) that with a pure CuS anode at the 100 th cycle (159.7 mAh/g). This phenomenon can be attributed to the synergistic action of CuS nanoparticles and rGO nanosheets in the “double-sandwich-like” CSG hybrids. These results indicate that CSG is an excellent anode material and has promising prospects in lithium ion batteries applications

  18. Strong lithium polysulfide chemisorption on electroactive sites of nitrogen-doped carbon composites for high-performance lithium-sulfur battery cathodes.

    Science.gov (United States)

    Song, Jiangxuan; Gordin, Mikhail L; Xu, Terrence; Chen, Shuru; Yu, Zhaoxin; Sohn, Hiesang; Lu, Jun; Ren, Yang; Duan, Yuhua; Wang, Donghai

    2015-03-27

    Despite the high theoretical capacity of lithium-sulfur batteries, their practical applications are severely hindered by a fast capacity decay, stemming from the dissolution and diffusion of lithium polysulfides in the electrolyte. A novel functional carbon composite (carbon-nanotube-interpenetrated mesoporous nitrogen-doped carbon spheres, MNCS/CNT), which can strongly adsorb lithium polysulfides, is now reported to act as a sulfur host. The nitrogen functional groups of this composite enable the effective trapping of lithium polysulfides on electroactive sites within the cathode, leading to a much improved electrochemical performance (1200 mAh g(-1) after 200 cycles). The enhancement in adsorption can be attributed to the chemical bonding of lithium ions by nitrogen functional groups in the MNCS/CNT framework. Furthermore, the micrometer-sized spherical structure of the material yields a high areal capacity (ca. 6 mAh cm(-2)) with a high sulfur loading of approximately 5 mg cm(-2), which is ideal for practical applications of the lithium-sulfur batteries. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Electrochemistry of Inorganic Nanocrystalline Electrode Materials for Lithium Batteries

    Directory of Open Access Journals (Sweden)

    C. W. Kwon

    2003-01-01

    much different from that of traditional crystalline ones because of their significant ‘surface effects’. In connection with that, the nanocrystalline cathode materials are reported to have an enhanced electrochemical activity when the first significative electrochemical step is insertion of Li ions (discharge process. The “electrochemical grafting” concept will be given as a plausible explanation. As illustrative examples, electrochemical behaviors of nanocrystalline manganese oxydes are presented.

  20. Electrochemical behavior of current collectors for lithium batteries in non-aqueous alkyl carbonate solution and surface analysis by ToF-SIMS

    International Nuclear Information System (INIS)

    Myung, Seung-Taek; Sasaki, Yusuke; Sakurada, Shuhei; Sun, Yang-Kook; Yashiro, Hitoshi

    2009-01-01

    Several metals (Cu, Fe, Al, Ti, and Cr) as current collector for lithium-ion battery were investigated to understand their electrochemical behavior and passivation process in a non-aqueous alkyl carbonate solution containing LiPF 6 salt. From cyclic voltammetric study, it was found that Cu and Fe metals were dissolved into the electrolyte below 4 V vs. Li/Li + . Alternatively, Al and Ti were stable up to 5 V vs. Li/Li + . Their scratched surfaces at 5 V vs. Li/Li + were polarized in a transient mode and it was found that the surfaces were passivated during the polarization test. Formed passive film was composed of two hybrid layers: outer layer by metal (Al and Ti) fluoride and inner by metal oxide, as confirmed by time-of-flight secondary ion mass spectroscopy. Presence of HF in the electrolyte was indispensible to form the metal fluoride layer on the oxide layer. The outer fluoride layer would protect the inner oxide layer and metal substrate from HF attack, bringing about satisfactory corrosion resistance under lithium-ion battery environment.

  1. In situ synthesis of Co3O4/graphene nanocomposite material for lithium-ion batteries and supercapacitors with high capacity and supercapacitance

    International Nuclear Information System (INIS)

    Wang Bei; Wang Ying; Park, Jinsoo; Ahn, Hyojun; Wang Guoxiu

    2011-01-01

    Highlights: → In situ solution-based preparation of Co 3 O 4 /graphene composite material. → Well dispersed Co 3 O 4 nanoparticles on graphene nanosheets. → Co 3 O 4 /graphene exhibits highly reversible lithium storage capacity. → Co 3 O 4 /graphene delivers superior supercapacitance up to 478 F g -1 . → Functional groups make contributions to the overall supercapacitance. - Abstract: Co 3 O 4 /graphene nanocomposite material was prepared by an in situ solution-based method under reflux conditions. In this reaction progress, Co 2+ salts were converted to Co 3 O 4 nanoparticles which were simultaneously inserted into the graphene layers, upon the reduction of graphite oxide to graphene. The prepared material consists of uniform Co 3 O 4 nanoparticles (15-25 nm), which are well dispersed on the surfaces of graphene nanosheets. This has been confirmed through observations by field emission scanning electron microscopy, transmission electron microscopy and atomic force microscopy. The prepared composite material exhibits an initial reversible lithium storage capacity of 722 mAh g -1 in lithium-ion cells and a specific supercapacitance of 478 F g -1 in 2 M KOH electrolyte for supercapacitors, which were higher than that of the previously reported pure graphene nanosheets and Co 3 O 4 nanoparticles. Co 3 O 4 /graphene nanocomposite material demonstrated an excellent electrochemical performance as an anode material for reversible lithium storage in lithium ion cells and as an electrode material in supercapacitors.

  2. Electrochemical studies of ferrocene in a lithium ion conducting organic carbonate electrolyte

    International Nuclear Information System (INIS)

    Laoire, Cormac O.; Plichta, Edward; Hendrickson, Mary; Mukerjee, Sanjeev; Abraham, K.M.

    2009-01-01

    We carried out a detailed study of the kinetics of oxidation of ferrocene (Fc) to ferrocenium ion (Fc + ) in the non-aqueous lithium ion conducting electrolyte composed of a solution of 1 M LiPF 6 in 1:1 EC:EMC solvent mixture. This study using cyclic (CV) and rotating disk electrode (RDE) voltammetry showed that the Fc 0 /Fc + redox couple is reversible in this highly concentrated electrolyte. The ferrocene and ferrocenium ion diffusion coefficients (D) were calculated from these results. In addition, the electron transfer rate constant (k 0 ) and the exchange current density for the oxidation of ferrocene were determined. A comparison of the kinetic data obtained from the two electrochemical techniques appears to show that the data from the RDE experiments are more reliable because they are collected under strict mass transport control. A Tafel slope of c.a. 79 mV/decade and a transfer coefficient α of 0.3 obtained from analysis of the RDE data for ferrocene oxidation suggest that the structure of the activated complex is closer to that of the oxidized specie due to strong interactions with the carbonate solvents. The experiments reported here are relevant to the study of redox reagents for the chemical overcharge protection of Li-ion batteries.

  3. Preparation and capacitive properties of lithium manganese oxide intercalation compound

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Fang; Xie, Yibing, E-mail: ybxie@seu.edu.cn [Southeast University, School of Chemistry and Chemical Engineering (China)

    2015-12-15

    Lithium manganese oxide intercalation compound (Li{sub 0.7}MnO{sub 2}) supported on titanium nitride nanotube array (TiN NTA) was applied as cathode electrode material for lithium-ion supercapacitor application. Li{sub 0.7}MnO{sub 2}/TiN NTA was fabricated through electrochemical deposition and simultaneous intercalation process using TiN NTA as a substrate, Mn(CH{sub 3}COO){sub 2} as manganese source, and Li{sub 2}SO{sub 4} as lithium source. The morphology and microstructure of the Li{sub 0.7}MnO{sub 2}/TiN NTA were characterized by scanning electron microscopy and X-ray diffraction analysis. The electrochemical performance of the Li{sub 0.7}MnO{sub 2}/TiN NTA was investigated by electrochemical impedance spectroscopy, cyclic voltammetry, and galvanostatic charge/discharge measurements. Li{sub 0.7}MnO{sub 2}/TiN NTA exhibited higher capacitive performance in Li{sub 2}SO{sub 4} electrolyte solution rather than that in Na{sub 2}SO{sub 4} electrolyte solution, which was due to the different intercalation effects of lithium-ion and sodium-ion. The specific capacitance was improved from 503.3 F g{sup −1} for MnO{sub 2}/TiN NTA to 595.0 F g{sup −1} for Li{sub 0.7}MnO{sub 2}/TiN NTA at a current density of 2 A g{sup −1} in 1.0 M Li{sub 2}SO{sub 4} electrolyte solution, which was due to the intercalation of lithium-ion for Li{sub 0.7}MnO{sub 2}. Li{sub 0.7}MnO{sub 2}/TiN NTA also kept 90.4 % capacity retention after 1000 cycles, presenting a good cycling stability. An all-solid-state lithium-ion supercapacitor was fabricated and showed an energy density of 82.5 Wh kg{sup −1} and a power density of 10.0 kW kg{sup −1}.

  4. Synthesis and electrochemical performance of hierarchical Sb2S3 nanorod-bundles for lithium-ion batteries

    Directory of Open Access Journals (Sweden)

    XIAOZHONG ZHOU

    2014-05-01

    Full Text Available Uniform hierarchical Sb2S3 nanorod-bundles were synthesised successfully by L-cysteine hydrochloride-assisted solvothermal treatment, and were then characterised by X-ray diffraction, field emission scanning electron microscopy, and high-resolution transmission electron microscopy, respectively. The electrochemical performance of the synthesised Sb2S3 nanorod-bundles was investigated by cyclic voltammetry and galvanostatic charge−discharge technique, respectively. This material was found to exhibit a high initial charge specific capacity of 803 mA h g-1 at a rate of 100 mA g-1, a good cyclability of 614 mA h g-1 at a rate of 100 mA g-1 after 30 cycles, and a good rate capability of 400 mA h g-1 at a rate of 500 mA g-1 when evaluated as an electrode candidate material for lithium-ion batteries.

  5. The effects of carbon distribution and thickness on the lithium storage properties of carbon-coated SnO_2 hollow nanofibers

    International Nuclear Information System (INIS)

    Zhou, Huimin; Li, Zhiyong; Qiu, Yiping; Xia, Xin

    2016-01-01

    To alleviate the enormous volume change problem of tin-based anodes for lithium ion batteries (LIBs), carbon-coated tin dioxide (SnO_2) hollow nanofibers were prepared by means of single-spinneret electrospinning followed by calcination and hydrothermal treatment. By varying the concentration of glucose and the reaction time during the hydrothermal coating process, the final product with different carbon distribution and thickness could be obtained. Galvanostatic charge/discharge was carried out to evaluate them as potential anode materials for LIBs. It was shown that the main effect of carbon distribution was to control the capacity retention rate, and the carbon thickness played the important role in lithium insertion/extraction properties. The optimum composite nanofibers could be prepared with glucose concentration of 10 mg/ml and hydrothermal time of 20 h, the carbon content and the specific surface area of which were 26.15% and 29.4 m"2/g, respectively. And this anode with both the carbon core and deposited thin carbon skin was able to deliver a high reversible capacity of 704.6 mAhg"−"1 and the capacity retention could retain 68.2% after 80 cycles. - Graphical abstract: Based on the electrochemical properties of carbon-coated hollow SnO2 anodes, how the carbon distribution and carbon thickness affect their performance are disscussed in groups. - Highlights: • The hollow SnO_2 nanofibers were carbon-coated by hydrothermal process. • The controlled distribution and thickness of carbon layer can be obtained. • The main effect of carbon distribution was to control the capacity retention rate. • The carbon thickness played the important role in lithium insertion/extraction properties.

  6. In-situ grown CNTs modified SiO2/C composites as anode with improved cycling stability and rate capability for lithium storage

    Science.gov (United States)

    Wang, Siqi; Zhao, Naiqin; Shi, Chunsheng; Liu, Enzuo; He, Chunnian; He, Fang; Ma, Liying

    2018-03-01

    Silica (SiO2) is regarded as one of the most promising anode materials for lithium ion batteries owing to its high theoretical specific capacity, relatively low operation potentials, abundance, environmental benignity and low cost. However, the low intrinsic electrical conductivity and large volume change of SiO2 during the discharge/charge cycles usually results in poor electrochemical performance. In this work, carbon nanotubes (CNTs) modified SiO2/C composites have been fabricated through an in-situ chemical vapor deposition method. The results show that the electrical conductivity of the SiO2/C/CNTs is visibly enhanced through a robust connection between the CNTs and SiO2/C particles. Compared with the pristine SiO2 and SiO2/C composites, the SiO2/C/CNTs composites display a high initial capacity of 1267.2 mA h g-1. Besides, an excellent cycling stability with the capacity of 315.7 mA h g-1 is achieved after 1000th cycles at a rate of 1 A g-1. The significantly improved electrochemical properties of the SiO2/C/CNTs composites are mainly attributed to the formation of three dimensional CNT networks in the SiO2/C substrate, which can not only shorten the Li-ion diffusion path but also relieve the volume change during the lithium-ion insertion/extraction processes.

  7. Lithium alloy negative electrodes

    Science.gov (United States)

    Huggins, Robert A.

    The 1996 announcement by Fuji Photo Film of the development of lithium batteries containing convertible metal oxides has caused a great deal of renewed interest in lithium alloys as alternative materials for use in the negative electrode of rechargeable lithium cells. The earlier work on lithium alloys, both at elevated and ambient temperatures is briefly reviewed. Basic principles relating thermodynamics, phase diagrams and electrochemical properties under near-equilibrium conditions are discussed, with the Li-Sn system as an example. Second-phase nucleation, and its hindrance under dynamic conditions plays an important role in determining deviations from equilibrium behavior. Two general types of composite microstructure electrodes, those with a mixed-conducting matrix, and those with a solid electrolyte matrix, are discussed. The Li-Sn-Si system at elevated temperatures, and the Li-Sn-Cd at ambient temperatures are shown to be examples of mixed-conducting matrix microstructures. The convertible oxides are an example of the solid electrolyte matrix type. Although the reversible capacity can be very large in this case, the first cycle irreversible capacity required to convert the oxides to alloys may be a significant handicap.

  8. Synthesis and electrochemical performance of Li2FeSiO4/C/carbon nanosphere composite cathode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Yang, Jinlong; Kang, Xiaochun; Hu, Lin; Gong, Xue; He, Daping; Peng, Tao; Mu, Shichun

    2013-01-01

    Highlights: •The Li 2 FeSiO 4 /C/CNS was prepared by effective double-carbon composite route. •The CNS as the conductivity belt connects the Li 2 FeSiO 4 /C particles. •The samples have a high capacity and excellent cyclic and rate performance. -- Abstract: Li 2 FeSiO 4 /C/carbon nanosphere (CNS) composites as cathode materials for lithium-ion batteries were synthesized by a simple hydro-chemical method. The double-carbon structural design of glucose pyrolysis-carbon (C) and CNS improved electrochemical performance of the composite where the CNS can build conductivity belts to connect the Li 2 FeSiO 4 /C particles and to favor electronic transmission. The exchange current density and the diffusion coefficient of lithium ions with the composite were 0.208 mA cm −2 and 1.06E−11 cm 2 S −1 , respectively, which were much larger than that of conventional Li 2 FeSiO 4 /C composite cathode materials (i = 0.131 mA cm −2 , D Li = 4.69E−12 cm 2 S −1 ). The electrochemical test results showed that the discharge capacity of 164.7 mA h g −1 could be obtained, and especially, after 60 cycles, 98.4% of the initial discharge capacity remained at 0.1 C of galvanostatic discharge in the potential range of 1.5–4.8 V (vs. Li/Li + ). In addition, the discharge capacity of 92.4 mA h g −1 at 5 C was easily recovered to 159.8 mA h g −1 at 0.1 C

  9. Electrochemical properties and lithium ion diffusion in Li4FeSbO6 studied by first principle

    Science.gov (United States)

    Jia, Mingzhen; Wang, Hongyan; Wang, Hui; Chen, Yuanzheng; Guo, Chunsheng; Gan, Liyong

    2017-10-01

    Due to the high capacity, Li-rich materials Li2MO3 (M = transition metal) have attracted considerable attention as the next generation of Li-ion batteries. Li4FeSbO6 is a new Li-rich layered oxide material with antiferromagnet honeycomb structure. In this work, the electrochemical behavior, charging process and oxygen stability of LixFeSbO6 (0 ≤ xextracted, the charge compensation is mainly contributed by the oxygen atoms through analyzing the Bader charges of each element. In addition, oxygen evolution reactions will occur in LixFeSbO6 (x ≤ 1.5), which will decay the capacities during cycling process. Finally, we calculated that the lithium ion can diffuse in a three-dimensional pathway with the activation barriers from 0.36 eV to 0.67 eV.

  10. Synthesis and structural characterization of defect spinels in the Lithium-Manganese-Oxide system

    CSIR Research Space (South Africa)

    Thackeray, MM

    1993-10-01

    Full Text Available Lithium-manganese-oxides prepared at moderate temperatures are under investigation as insertion electrodes for rechargeable lithium batteries. The structures of two defect-spinel compounds synthesised by the reaction of MnCO3 and Li2CO3 at 400...

  11. Method of fabricating electrodes including high-capacity, binder-free anodes for lithium-ion batteries

    Science.gov (United States)

    Ban, Chunmei; Wu, Zhuangchun; Dillon, Anne C.

    2017-01-10

    An electrode (110) is provided that may be used in an electrochemical device (100) such as an energy storage/discharge device, e.g., a lithium-ion battery, or an electrochromic device, e.g., a smart window. Hydrothermal techniques and vacuum filtration methods were applied to fabricate the electrode (110). The electrode (110) includes an active portion (140) that is made up of electrochemically active nanoparticles, with one embodiment utilizing 3d-transition metal oxides to provide the electrochemical capacity of the electrode (110). The active material (140) may include other electrochemical materials, such as silicon, tin, lithium manganese oxide, and lithium iron phosphate. The electrode (110) also includes a matrix or net (170) of electrically conductive nanomaterial that acts to connect and/or bind the active nanoparticles (140) such that no binder material is required in the electrode (110), which allows more active materials (140) to be included to improve energy density and other desirable characteristics of the electrode. The matrix material (170) may take the form of carbon nanotubes, such as single-wall, double-wall, and/or multi-wall nanotubes, and be provided as about 2 to 30 percent weight of the electrode (110) with the rest being the active material (140).

  12. A Novel 2D Porous Print Fabric-like α-Fe_2O_3 Sheet with High Performance as the Anode Material for Lithium-ion Battery

    International Nuclear Information System (INIS)

    Zhang, Suyue; Zhang, Peigen; Xie, Anjian; Li, Shikuo; Huang, Fangzhi; Shen, Yuhua

    2016-01-01

    Anode materials are very crucial in lithium ion batteries. Exploring the simple and low cost production of anodes with excellent electrochemical performance remains a great challenge. Here, we used natural flower spikes of Typha orientalis as the bio-templates and organizers to prepare a novel two-dimensional (2D) porous print fabric-like α-Fe_2O_3 sheet with thickness of about 30 nm. The prepared large-area sheets were orderly assembled by many nanosheets or nanoparticles, and two kinds of pore structures, such as pores with average diameter of about 50 nm or pore channels with aspect ratio of ca. 4, presented between adjacent nanosheets. The pre-treatment by ammonium for flower spikes has a great effect on the microstructure and electrochemical performance of the products. As the anode material for lithium ion battery (LIB), the as-obtained porous print fabric-like α-Fe_2O_3 sheets show an initial discharge capacity of 2264 mA h g"−"1 and the specific capacity of 1028 mA h g"−"1 after 100 cycles at a current density of 500 mA g"−"1, which is higher than the theoretical capacity of α-Fe_2O_3 (1007 mA h g"−"1). This highly reversible capacity is attributed to the very thin large-area sheet structure, and many pores or pore channels among the interconnected nanosheets, which could increase lithium-ion mobility, facilitate the transport of electrons and shorten the distance for Li"+ diffusion, and also buffer large volume changes of the anodes during lithium insertion and extraction at the same time. The synthesis process is very simple, providing a low-cost production approach toward high-performance energy storage materials.

  13. Insertion of lithium in Nb2O5

    International Nuclear Information System (INIS)

    Alves, M.C.M.; Bulhoes, L.O.S.; Castro, S.C.

    1990-01-01

    The electrode process during the reduction and oxidation of Nb sub(2) O sub(5) by cyclic voltametry was characterized. The surface analysis by X-ray photo electronic spectroscopy allowed characterize the surface processes, that happening during the insertion reaction. (author)

  14. Lithium recovery from brine using a λ-MnO2/activated carbon hybrid supercapacitor system.

    Science.gov (United States)

    Kim, Seoni; Lee, Jaehan; Kang, Jin Soo; Jo, Kyusik; Kim, Seonghwan; Sung, Yung-Eun; Yoon, Jeyong

    2015-04-01

    Lithium is one of the most important elements in various fields including energy storage, medicine manufacturing and the glass industry, and demands for lithium are constantly increasing these days. The lime soda evaporation process using brine lake water is the major extraction method for lithium, but this process is not only inefficient and time-consuming but also causes a few environmental problems. Electrochemical recovery processes of lithium ions have been proposed recently, but the better idea for the silver negative electrodes used in these systems is required to reduce its cost or increase long term stability. Here, we report an electrochemical lithium recovery method based on a λ-MnO2/activated carbon hybrid supercapacitor system. In this system, lithium ions and counter anions are effectively captured at each electrode with low energy consumption in a salt solution containing various cationic species or simulated Salar de Atacama brine lake water in Chile. Furthermore, we designed this system as a flow process for practical applications. By experimental analyses, we confirmed that this system has high selectivity and long-term stability, with its performance being retained even after repetitive captures and releases of lithium ions. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Synthesis and electrochemical properties of ZnMn_2O_4 anode for lithium-ion batteries

    International Nuclear Information System (INIS)

    Feng, Chuanqi; Wang, Wei; Chen, Xiao; Wang, Shiquan; Guo, Zaiping

    2015-01-01

    Graphical abstract: ZnMn_2O_4 nanoparticles were prepared through the rheological phase reaction method (R-ZMO) or the mixed solvothermal method(M-ZMO). The particles of M-ZMO were clustered together to form uniform microspheres morphology. The M-ZMO behaved higher reversible capacity and better cycle performance than that of R-ZMO. - Highlights: • ZnMn_2O_4 nanoparticles were prepared through the rheological phase reaction method (R-ZMO) or the mixed solvothermal method (M-ZMO). • The M-ZMO behaved higher reversible capacity and better cycle performance than that of R-ZMO. • The morphology and cell parameters of ZnMn_2O_4 are important effects on its electrochemical properties. • The diffusion coefficient of Li"+ in M-ZMO is beneficial for M-ZMO to be used an anode. - Abstract: The precursors of ZnMn_2O_4 were synthesized by different methods (the rheological phase reaction method or the mixed solvothermal method). The precursors were heat-treated at a suitable temperature to obtain the expected product (ZnMn_2O_4). The synthesized samples were characterized by X-ray diffraction, scanning electron microscopy, and transmission electron microscopy. The electrochemical properties of the samples were also investigated. The results show that ZnMn_2O_4 was synthesized successfully. The particles of ZnMn_2O_4 were irregular quasi-spheres with sizes of about 50 nm. The ZnMn_2O_4 nanoparticles synthesized through the mixed solvothermal method were clustered together to form microspheres about 1 μm in diameter. The electrochemical testing results showed that the ZnMn_2O_4 synthesized through the mixed solvothermal method featured higher reversible capacity and better cycling performance than the sample synthesized by the rheological phase reaction method. The ZnMn_2O_4 synthesized through the mixed solvothermal method could be a promising anode material for lithium ion battery application.

  16. Recent Advances in Porous Carbon Materials for Electrochemical Energy Storage.

    Science.gov (United States)

    Wang, Libin; Hu, Xianluo

    2018-06-18

    Climate change and the energy crisis have promoted the rapid development of electrochemical energy-storage devices. Owing to many intriguing physicochemical properties, such as excellent chemical stability, high electronic conductivity, and a large specific surface area, porous carbon materials have always been considering as a promising candidate for electrochemical energy storage. To date, a wide variety of porous carbon materials based upon molecular design, pore control, and compositional tailoring have been proposed for energy-storage applications. This focus review summarizes recent advances in the synthesis of various porous carbon materials from the view of energy storage, particularly in the past three years. Their applications in representative electrochemical energy-storage devices, such as lithium-ion batteries, supercapacitors, and lithium-ion hybrid capacitors, are discussed in this review, with a look forward to offer some inspiration and guidelines for the exploitation of advanced carbon-based energy-storage materials. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Influence of particle size and fluorination ratio of CFx precursor compounds on the electrochemical performance of C–FeF2 nanocomposites for reversible lithium storage

    Directory of Open Access Journals (Sweden)

    Ben Breitung

    2013-11-01

    Full Text Available Systematical studies of the electrochemical performance of CFx-derived carbon–FeF2 nanocomposites for reversible lithium storage are presented. The conversion cathode materials were synthesized by a simple one-pot synthesis, which enables a reactive intercalation of nanoscale Fe particles in a CFx matrix, and the reaction of these components to an electrically conductive C–FeF2 compound. The pretreatment and the structure of the utilized CFx precursors play a crucial role in the synthesis and influence the electrochemical behavior of the conversion cathode material. The particle size of the CFx precursor particles was varied by ball milling as well as by choosing different C/F ratios. The investigations led to optimized C–FeF2 conversion cathode materials that showed specific capacities of 436 mAh/g at 40 °C after 25 cycles. The composites were characterized by Raman spectroscopy, X-Ray diffraction measurements, electron energy loss spectroscopy and TEM measurements. The electrochemical performances of the materials were tested by galvanostatic measurements.

  18. High rate capacity nanocomposite lanthanum oxide coated lithium zinc titanate anode for rechargeable lithium-ion battery

    International Nuclear Information System (INIS)

    Tang, Haoqing; Zan, Lingxing; Zhu, Jiangtao; Ma, Yiheng; Zhao, Naiqin; Tang, Zhiyuan

    2016-01-01

    Lithium zinc titanate (Li_2ZnTi_3O_8) is an important titanium material of promising candidates for anode materials with superior electrochemical performance and thus has attracted extensive attention. Herein, high capacity, stable Li_2ZnTi_3O_8/La_2O_3 nanocomposite for lithium-ion battery anode is prepared by a facile strategy. Compared to unmodified Li_2ZnTi_3O_8, the Li_2ZnTi_3O_8/La_2O_3 electrode display a high specific capacity of 188.6 mAh g"−"1 and remain as high as 147.7 mAh g"−"1 after 100 cycles at 2.0 A g"−"1. Moreover, a reversible capacity of 76.3 mAh g"−"1 can be obtained after 1000 cycles at 2.0 A g"−"1 and the retention is 42.7% for Li_2ZnTi_3O_8/La_2O_3, which is much higher than un-coated Li_2ZnTi_3O_8. The superior lithium storage performances of the Li_2ZnTi_3O_8/La_2O_3 can be ascribed to the stable layer of protection, small particle size and large surface area. Cyclic voltammograms result reveals that the La_2O_3 coating layer reduces the polarization and improves the electrochemical activity of anode. - Highlights: • Nano layer La_2O_3 coated Li_2ZnTi_3O_8 particles have been prepared via a suspension mixing process followed by heat treatment. • Coated Li_2ZnTi_3O_8 has enhanced high rate capability, cyclic stability and long lifespan performance. • Electrochemical properties were tested in a charge/discharge voltage range of 3.0–0.05 V (vs. Li/Li"+).

  19. Electrochemical Investigation of The Catalytical Processes During Sulfuric Acid Production

    DEFF Research Database (Denmark)

    Bjerrum, Niels; Petrushina, Irina; Berg, Rolf W.

    1995-01-01

    The electrochemical behavior of molten K2S2O7 and its mixtures with V2O5 [2–20 mole percent (m/o) V2O5] was studiedat 440°C in argon, by using cyclic voltammetry on a gold electrode. The effect of the addition of sulfate and lithium ions onthe electrochemical processes in the molten potassium...

  20. Effects of lithium insertion on thermal conductivity of silicon nanowires

    International Nuclear Information System (INIS)

    Xu, Wen; Zhang, Gang; Li, Baowen

    2015-01-01

    Recently, silicon nanowires (SiNWs) have been applied as high-performance Li battery anodes, since they can overcome the pulverization and mechanical fracture during lithiation. Although thermal stability is one of the most important parameters that determine safety of Li batteries, thermal conductivity of SiNWs with Li insertion remains unclear. In this letter, using molecular dynamics simulations, we study room temperature thermal conductivity of SiNWs with Li insertion. It is found that compared with the pristine SiNW, there is as much as 60% reduction in thermal conductivity with 10% concentration of inserted Li atoms, while under the same impurity concentration the reduction in thermal conductivity of the mass-disordered SiNW is only 30%. With lattice dynamics calculations and normal mode decomposition, it is revealed that the phonon lifetimes in SiNWs decrease greatly due to strong scattering of phonons by vibrational modes of Li atoms, especially for those high frequency phonons. The observed strong phonon scattering phenomenon in Li-inserted SiNWs is similar to the phonon rattling effect. Our study serves as an exploration of thermal properties of SiNWs as Li battery anodes or weakly coupled with impurity atoms

  1. A series of spinel phase cathode materials prepared by a simple hydrothermal process for rechargeable lithium batteries

    Science.gov (United States)

    Liang, Yan-Yu; Bao, Shu-Juan; Li, Hu-Lin

    2006-07-01

    A series of spinel-structured materials have been prepared by a simple hydrothermal procedure in an aqueous medium. The new synthetic method is time and energy saving i.e., no further thermal treatment and extended grinding. The main experimental process involved the insertion of lithium into electrolytic manganese dioxide with glucose as a mild reductant in an autoclave. Both the hydrothermal temperature and the presence of glucose play the critical roles in determining the final spinel integrity. Particular electrochemical performance has also been systematically explored, and the results show that Al 3+, F - co-substituted spinels have the best combination of initial capacity and capacity retention among all these samples, exhibited the initial capacity of 115 mAh/g and maintained more than 90% of the initial value at the 50th cycle.

  2. Non-aqueous electrolyte for lithium-ion battery

    Science.gov (United States)

    Zhang, Lu; Zhang, Zhengcheng; Amine, Khalil

    2014-04-15

    The present technology relates to stabilizing additives and electrolytes containing the same for use in electrochemical devices such as lithium ion batteries and capacitors. The stabilizing additives include triazinane triones and bicyclic compounds comprising succinic anhydride, such as compounds of Formulas I and II described herein.

  3. Electrochemical properties of SnO{sub 2}/carbon composite materials as anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jie [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Zhao Hailei, E-mail: hlzhao@ustb.edu.cn [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Beijing Key Lab of New Energy Materials and Technologies, Beijing 100083 (China); Liu Xiaotong; Wang Jing; Wang Chunmei [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China)

    2011-07-15

    Highlights: > SnO{sub 2}/carbon powders with a cauliflower-like particle structure were synthesized. > Post-annealing can improve the electrochemical properties of SnO{sub 2}/C composite. > The 500 deg. C-annealed SnO{sub 2}/C shows the best electrochemical performance. > The lithium ion diffusion coefficients of the SnO{sub 2}/C electrodes were calculated. - Abstract: SnO{sub 2}/carbon composite anode materials were synthesized from SnCl{sub 4}.5H{sub 2}O and sucrose via a hydrothermal route and a post heat-treatment. The synthesized spherical SnO{sub 2}/carbon powders show a cauliflower-like micro-sized structure. High annealing temperature results in partial reduction of SnO{sub 2}. Metallic Sn starts to emerge at 500 deg. C. High Sn content in SnO{sub 2}/carbon composite is favorable for the increase of initial coulombic efficiency but not for the cycling stability. The SnO{sub 2}/carbon annealed at 500 deg. C exhibits high specific capacity ({approx}400 mAh g{sup -1}), stable cycling performance and good rate capability. The generation of Li{sub 2}O in the first lithiation process can prevent the aggregation of active Sn, while the carbon component can buffer the big volume change caused by lithiation/delithiation of active Sn. Both of them make contribution to the better cycle stability.

  4. Synthesis and structural characterization of defect spinels in the lithium-manganese-oxide system

    CSIR Research Space (South Africa)

    Thackeray, MM

    1993-10-01

    Full Text Available Lithium-manganese-oxides prepared at moderate temperatures are under investigation as insertion electrodes for rechargeable lithium batteries. The structures of two defect-spinel compounds synthesized by the reaction of MnCO3 and Li2CO3 at 400°C...

  5. Nanocarbon networks for advanced rechargeable lithium batteries.

    Science.gov (United States)

    Xin, Sen; Guo, Yu-Guo; Wan, Li-Jun

    2012-10-16

    Carbon is one of the essential elements in energy storage. In rechargeable lithium batteries, researchers have considered many types of nanostructured carbons, such as carbon nanoparticles, carbon nanotubes, graphene, and nanoporous carbon, as anode materials and, especially, as key components for building advanced composite electrode materials. Nanocarbons can form efficient three-dimensional conducting networks that improve the performance of electrode materials suffering from the limited kinetics of lithium storage. Although the porous structure guarantees a fast migration of Li ions, the nanocarbon network can serve as an effective matrix for dispersing the active materials to prevent them from agglomerating. The nanocarbon network also affords an efficient electron pathway to provide better electrical contacts. Because of their structural stability and flexibility, nanocarbon networks can alleviate the stress and volume changes that occur in active materials during the Li insertion/extraction process. Through the elegant design of hierarchical electrode materials with nanocarbon networks, researchers can improve both the kinetic performance and the structural stability of the electrode material, which leads to optimal battery capacity, cycling stability, and rate capability. This Account summarizes recent progress in the structural design, chemical synthesis, and characterization of the electrochemical properties of nanocarbon networks for Li-ion batteries. In such systems, storage occurs primarily in the non-carbon components, while carbon acts as the conductor and as the structural buffer. We emphasize representative nanocarbon networks including those that use carbon nanotubes and graphene. We discuss the role of carbon in enhancing the performance of various electrode materials in areas such as Li storage, Li ion and electron transport, and structural stability during cycling. We especially highlight the use of graphene to construct the carbon conducting

  6. Lithium position and occupancy fluctuations in a cathode during charge/discharge cycling of lithium-ion battery

    International Nuclear Information System (INIS)

    Sharma, N.; Yu, D.; Zhu, Y.; Wu, Y.; Peterson, V. K.

    2012-01-01

    Lithium-ion batteries are undergoing rapid development to meet the energy demands of the transportation and renewable energy-generation sectors. The capacity of a lithium-ion battery is dependent on the amount of lithium that can be reversibly incorporated into the cathode. Neutron diffraction provides greater sensitivity towards lithium relative to other diffraction techniques. In conjunction with the penetration depth afforded by neutron diffraction, the information concerning lithium gained in a neutron diffraction study allows commercial lithium-ion batteries to be explored with respect to the lithium content in the whole cathode. Furthermore, neutron diffraction instruments featuring area detectors that allow relatively fast acquisitions enable perturbations of lithium location and occupancy in the cathode during charge/discharge cycling to be determined in real time. Here, we present the time, current, and temperature dependent lithium transfer occurring within a cathode functioning under conventional charge-discharge cycling. The lithium location and content, oxygen positional parameter, and lattice parameter of the Li 1+y Mn 2 0 4 cathode are measured and linked to the battery's charge/discharge characteristics (performance). We determine that the lithium-transfer mechanism involves two crystallographic sites, and that the mechanism differs between discharge and charge, explaining the relative ease of discharging (compared with charging) this material. Furthermore, we find that the rate of change of the lattice is faster on charging than discharging, and is dependent on the lithium insertion/ extraction processes (e.g. dependent on how the site occupancies evolve). Using in situ neutron diffraction data the atomic-scale understanding of cathode functionality is revealed, representing detailed information that can be used to direct improvements in battery performance at both the practical and fundamental level.

  7. Mitigating Thermal Runaway Risk in Lithium Ion Batteries

    Science.gov (United States)

    Darcy, Eric; Jeevarajan, Judy; Russell, Samuel

    2014-01-01

    The JSC/NESC team has successfully demonstrated Thermal Runaway (TR) risk reduction in a lithium ion battery for human space flight by developing and implementing verifiable design features which interrupt energy transfer between adjacent electrochemical cells. Conventional lithium ion (li-Ion) batteries can fail catastrophically as a result of a single cell going into thermal runaway. Thermal runaway results when an internal component fails to separate electrode materials leading to localized heating and complete combustion of the lithium ion cell. Previously, the greatest control to minimize the probability of cell failure was individual cell screening. Combining thermal runaway propagation mitigation design features with a comprehensive screening program reduces both the probability, and the severity, of a single cell failure.

  8. Electrochemical cell and method of assembly

    Science.gov (United States)

    Shimotake, Hiroshi; Voss, Ernst C. H.; Bartholme, Louis G.

    1979-01-01

    A method of preparing an electrochemical cell is disclosed which permits the assembly to be accomplished in air. The cell includes a metal sulfide as the positive electrode reactant, lithium alloy as the negative electrode reactant and an alkali metal, molten salt electrolyte. Positive electrode reactant is introduced as Li.sub.2 FeS.sub.2, a single-phase compound produced by the reaction of Li.sub.2 S and FeS. The use of this compound permits introduction of lithium in an oxidized form. Additional lithium can be introduced in the negative electrode structure enclosed within an aluminum foil envelope between layers of porous aluminum. Molten salt electrolyte is added after assembly and evacuation of the cell by including an interelectrode separator that has been prewet with an organic solution of KCl.

  9. Impedance Analysis of Silicon Nanowire Lithium Ion Battery Anodes

    KAUST Repository

    Ruffo, Riccardo; Hong, Seung Sae; Chan, Candace K.; Huggins, Robert A.; Cui, Yi

    2009-01-01

    The impedance behavior of silicon nanowire electrodes has been investigated to understand the electrochemical process kinetics that influences the performance when used as a high-capacity anode in a lithium ion battery. The ac response was measured

  10. Progress in Application of CNTs in Lithium-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Li Li

    2014-01-01

    Full Text Available The lithium-ion battery is widely used in the fields of portable devices and electric cars with its superior performance and promising energy storage applications. The unique one-dimensional structure formed by the graphene layer makes carbon nanotubes possess excellent mechanical, electrical, and electrochemical properties and becomes a hot material in the research of lithium-ion battery. In this paper, the applicable research progress of carbon nanotubes in lithium-ion battery is described, and its future development is put forward from its two aspects of being not only the anodic conductive reinforcing material and the cathodic energy storage material but also the electrically conductive framework material.

  11. Method of preparing an electrochemical cell in uncharged state

    Science.gov (United States)

    Shimotake, Hiroshi; Bartholme, Louis G.; Arntzen, John D.

    1977-02-01

    A secondary electrochemical cell is assembled in an uncharged state for the preparation of a lithium alloy-transition metal sulfide cell. The negative electrode includes a material such as aluminum or silicon for alloying with lithium as the cell is charged. The positive electrode is prepared by blending particulate lithium sulfide, transition metal powder and electrolytic salt in solid phase. The mixture is simultaneously heated to a temperature in excess of the melting point of the electrolyte and pressed onto an electrically conductive substrate to form a plaque. The plaque is assembled as a positive electrode within the cell. During the first charge cycle lithium alloy is formed within the negative electrode and transition metal sulfide such as iron sulfide is produced within the positive electrode.

  12. Two-dimensional MoS2-graphene hybrid nanosheets for high gravimetric and volumetric lithium storage

    Science.gov (United States)

    Deng, Yakai; Ding, Lixin; Liu, Qixing; Zhan, Liang; Wang, Yanli; Yang, Shubin

    2018-04-01

    Two-dimensional (2D) MoS2-graphene (MoS2-G) hybrid is fabricated simultaneously and scalablely with an efficient electrochemical exfoliation approach from the combined bulk MoS2-graphite wafer. The as-prepared 2D MoS2-G hybrid is tightly covered with each other with lateral sizes of 600 nm to few micrometers and can be directly assembled to flexible films for lithium storage. When used as anode material for lithium ion battery, the resultant MoS2-G hybrid film exhibits both high gravimetric (750 mA h g-1 at 50 mA g-1) and volumetric capacities (1200 mA h cm-3 at 0.1 mA cm-2). Such excellent electrochemical performance should attributed to the unique 2D structure and good conductive graphene network, which not only facilitates the diffusion of lithium ions, but also improves the fast transfer of electrons, satisfying the kinetics requirements for rapid lithium storage.

  13. Lithium Superionic Conductor Li9.42Si1.02P2.1S9.96O2.04 with Li10GeP2S12-Type Structure in the Li2S–P2S5–SiO2 Pseudoternary System: Synthesis, Electrochemical Properties, and Structure–Composition Relationships

    International Nuclear Information System (INIS)

    Hori, Satoshi; Suzuki, Kota; Hirayama, Masaaki; Kato, Yuki; Kanno, Ryoji

    2016-01-01

    Lithium superionic conductors with the Li 10 GeP 2 S 12 (LGPS)-type structure are promising materials for use as solid electrolytes in the next-generation lithium batteries. A novel member of the LGPS family, Li 9.42 Si 1.02 P 2.1 S 9.96 O 2.04 (LSiPSO), and its solid solutions were synthesized by quenching from 1273 K in the Li 2 S–P 2 S 5 –SiO 2 pseudoternary system. The material exhibited an ionic conductivity as high as 3.2 × 10 −4 S cm −1 at 298 K, as well as the high electrochemical stability to lithium metal, which was improved by the introduction of oxygen into the LGPS-type structure. An all-solid-state cell with a lithium metal anode and LSiPSO as the separator showed excellent performance with a high reversibility of 100%. Thus, oxygen doping is an effective way of improving the electrochemical stability of LGPS-type structure.

  14. Metal-organic frameworks for lithium ion batteries and supercapacitors

    International Nuclear Information System (INIS)

    Ke, Fu-Sheng; Wu, Yu-Shan; Deng, Hexiang

    2015-01-01

    Porous materials have been widely used in batteries and supercapacitors attribute to their large internal surface area (usually 100–1000 m 2 g −1 ) and porosity that can favor the electrochemical reaction, interfacial charge transport, and provide short diffusion paths for ions. As a new type of porous crystalline materials, metal-organic frameworks (MOFs) have received huge attention in the past decade due to their unique properties, i.e. huge surface area (up to 7000 m 2 g −1 ), high porosity, low density, controllable structure and tunable pore size. A wide range of applications including gas separation, storage, catalysis, and drug delivery benefit from the recent fast development of MOFs. However, their potential in electrochemical energy storage has not been fully revealed. Herein, the present mini review appraises recent and significant development of MOFs and MOF-derived materials for rechargeable lithium ion batteries and supercapacitors, to give a glimpse into these potential applications of MOFs. - Graphical abstract: MOFs with large surface area and high porosity can offer more reaction sites and charge carriers diffusion path. Thus MOFs are used as cathode, anode, electrolyte, matrix and precursor materials for lithium ion battery, and also as electrode and precursor materials for supercapacitors. - Highlights: • MOFs have potential in electrochemical area due to their high porosity and diversity. • We summarized and compared works on MOFs for lithium ion battery and supercapacitor. • We pointed out critical challenges and provided possible solutions for future study

  15. Sol-Gel Synthesis and in Situ X-ray Diffraction Study of Li3Nd3W2O12 as a Lithium Container.

    Science.gov (United States)

    Luo, Minghe; Yu, Haoxiang; Cheng, Xing; Ye, Wuquan; Zhu, Haojie; Liu, Tingting; Peng, Na; Shui, Miao; Shu, Jie

    2018-04-18

    In this work, garnet-framework Li 3 Nd 3 W 2 O 12 as a novel insertion-type anode material has been prepared via a facile sol-gel method and examined as a lithium container for lithium ion batteries (LIBs). Li 3 Nd 3 W 2 O 12 shows a charge capacity of 225 mA h g -1 at 50 mA g -1 , and with the current density increasing up to 500 mA g -1 , the charge capacity can still be maintained at 186 mA h g -1 . After cycling at 500 mA g -1 for 500 cycles, Li 3 Nd 3 W 2 O 12 retains about 85% of its first charge capacity changed from 190.2 to 161 mA h g -1 . Furthermore, in situ X-ray diffraction technique is adopted for the understanding of the insertion/extraction mechanism of Li 3 Nd 3 W 2 O 12 . The full-cell configuration LiFePO 4 /Li 3 Nd 3 W 2 O 12 is also assembled to evaluate the potential of Li 3 Nd 3 W 2 O 12 for practical application. These results show that Li 3 Nd 3 W 2 O 12 is such a promising anode material for LIBs with excellent electrochemical performance and stable structure.

  16. The use of anions with sulfate function in electrolyte for lithium battery. Study of transport mechanism; Utilisation d'anions a fonction sulfate dans des electrolytes pour batterie au lithium. Etude des mecanismes de transport

    Energy Technology Data Exchange (ETDEWEB)

    Chauvin, Ch.

    2005-05-15

    Lithium salts based on oligo-ether sulfate were synthesized and characterised. They incorporate oxy-ethylene units which enable the lithium cation salvation and, potentially, their use as ionic liquids. Their properties as lithium salts dissolved in liquid or polymer electrolytes were evaluated. Their electrochemical and thermal stabilities are sufficient for lithium battery application. Due to their weak dissociation in POE, their conductivities are fairly low. On the other hand, they have high cationic transference numbers. In mixture with usual salts as LiTFSI, they provide a good compromise between conductivities/transference number/cost. The second part of this study deals with the synthesis and characterisation of an ionomer with sulfate function and polyether backbone. The electrochemical, physical and chemical properties of this material show that it could be used as polymer electrolyte. Its potential as cross-linked gelled polymer electrolyte is outstanding. Structural analyses on an ionomeric monocrystal have been corroborated with quantum chemistry calculations. (author)

  17. Anode Improvement in Rechargeable Lithium-Sulfur Batteries.

    Science.gov (United States)

    Tao, Tao; Lu, Shengguo; Fan, Ye; Lei, Weiwei; Huang, Shaoming; Chen, Ying

    2017-12-01

    Owing to their theoretical energy density of 2600 Wh kg -1 , lithium-sulfur batteries represent a promising future energy storage device to power electric vehicles. However, the practical applications of lithium-sulfur batteries suffer from poor cycle life and low Coulombic efficiency, which is attributed, in part, to the polysulfide shuttle and Li dendrite formation. Suppressing Li dendrite growth, blocking the unfavorable reaction between soluble polysulfides and Li, and improving the safety of Li-S batteries have become very important for the development of high-performance lithium sulfur batteries. A comprehensive review of various strategies is presented for enhancing the stability of the anode of lithium sulfur batteries, including inserting an interlayer, modifying the separator and electrolytes, employing artificial protection layers, and alternative anodes to replace the Li metal anode. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Lithium-Excess Research of Cathode Material Li₂MnTiO₄ for Lithium-Ion Batteries.

    Science.gov (United States)

    Zhang, Xinyi; Yang, Le; Hao, Feng; Chen, Haosen; Yang, Meng; Fang, Daining

    2015-11-20

    Lithium-excess and nano-sized Li 2+x Mn₁ - x /2 TiO₄ ( x = 0, 0.2, 0.4) cathode materials were synthesized via a sol-gel method. The X-ray diffraction (XRD) experiments indicate that the obtained main phases of Li 2.0 MnTiO₄ and the lithium-excess materials are monoclinic and cubic, respectively. The scanning electron microscope (SEM) images show that the as-prepared particles are well distributed and the primary particles have an average size of about 20-30 nm. The further electrochemical tests reveal that the charge-discharge performance of the material improves remarkably with the lithium content increasing. Particularly, the first discharging capacity at the current of 30 mA g -1 increases from 112.2 mAh g -1 of Li 2.0 MnTiO₄ to 187.5 mAh g -1 of Li 2.4 Mn 0.8 TiO₄. In addition, the ex situ XRD experiments indicate that the monoclinic Li₂MnTiO₄ tends to transform to an amorphous state with the extraction of lithium ions, while the cubic Li₂MnTiO₄ phase shows better structural reversibility and stability.

  19. Electrochemical studies of calcium-lithium alloys in thionyl chloride electrolyte systems

    Science.gov (United States)

    Gupta, V. K.; Fritts, D. H.

    The corrosion of the calcium anode in the calcium thionyl chloride cell has been a persistent problem, which has kept this otherwise attractive couple from use. Investigations of cells with anodes made from calcium/calcium-lithium alloys are reported. These anodes were chosen in hopes of obtaining synergistic results, namely a stable anode surface film vs. pure calcium, and a higher melting point than lithium anodes. Results indicate that some degree of synergism does exist, but that the surface film is not sufficiently stable to protect the anode from continuous corrosion. It is concluded that the stability problem is one of a mechanical shedding of the film which occurs independent of lithium content. Also, a change in the electrolyte salt is the most promising approach to the calcium corrosion problem.

  20. Role of Disorder in Enhancing Lithium-Ion Battery Performance

    DEFF Research Database (Denmark)

    Yue, Yuanzheng; He, W.

    and type of disorder, material performances can be significantly enhanced. Disorder can be tuned by doping, calcination, redox reaction, composition tuning, and so on. Recently we have fabricated a cathode material for lithium ion battery by introducing heterostructure and disorder into the material...... material exhibits the extremely high reversible lithium ion capacity and extraordinary rate capability with high cycling stability at high discharge current. In this presentation we demonstrate that the disorder plays a decisive role in achieving those exceptional electrochemical performances. We describe...... how the disorder affects the migration of both lithium ions and electrons. It is found that both the modified glassy surface and the heterogeneous superlattice structure greatly contribute to the extremely high discharge/charge rates owing to the enhanced storage capacity of lithium ions and ultrafast...

  1. Ionic Liquid-Doped Gel Polymer Electrolyte for Flexible Lithium-Ion Polymer Batteries

    Science.gov (United States)

    Zhang, Ruisi; Chen, Yuanfen; Montazami, Reza

    2015-01-01

    Application of gel polymer electrolytes (GPE) in lithium-ion polymer batteries can address many shortcomings associated with liquid electrolyte lithium-ion batteries. Due to their physical structure, GPEs exhibit lower ion conductivity compared to their liquid counterparts. In this work, we have investigated and report improved ion conductivity in GPEs doped with ionic liquid. Samples containing ionic liquid at a variety of volume percentages (vol %) were characterized for their electrochemical and ionic properties. It is concluded that excess ionic liquid can damage internal structure of the batteries and result in unwanted electrochemical reactions; however, samples containing 40–50 vol % ionic liquid exhibit superior ionic properties and lower internal resistance compared to those containing less or more ionic liquids.

  2. Controllable growth of MoS{sub 2}/C flower-like microspheres with enhanced electrochemical performance for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Xiong, Q.Q., E-mail: zjxqq@hdu.edu.cn; Ji, Z.G.

    2016-07-15

    Tailored design/fabrication of hierarchical porous advanced electrodes is of great importance for developing high-performance power sources. Herein, we report a facile solvothermal method for fabrication of hierarchical porous MoS{sub 2}/C flower-like microspheres. Interestingly, the obtained MoS{sub 2}/C microspheres are composed of interconnected secondary thin nanoflakes and an amorphous carbon layer. As an anode material for lithium ion batteries, the resultant MoS{sub 2}/C flower-like microspheres electrode delivers a high specific capacity of 1125.9 mAh g{sup −1} and good cycle capability (916.6 mAh g{sup −1} at 200 mA g{sup −1} up to 400 cycles), as well as enhanced rate performance. The excellent electrochemical performance is attributed to the unique porous composite architecture with fast transportation of ion/electron and good strain accommodation during the lithiation/delithiation reaction. Our research may pave the way for construction of other high-performance metal sulfides electrodes for electrochemical energy storage. - Graphical abstract: We report a facile solvothermal method for fabrication of hierarchical porous MoS{sub 2}/C flower-like microspheres composed of interconnected thin nanoflakes and an amorphous carbon layer. As an anode material for LIBs, MoS{sub 2}/C flower-like microspheres electrode delivers enhanced electrochemical performance. - Highlights: • We prepared MoS{sub 2}/C flower-like microspheres via a facile solvothermal method. • The microsphere consists of interconnected nanoflake and an amorphous carbon layer. • The MoS{sub 2}/C microspheres show high capacity and good rate performance.

  3. Copper Antimonide Nanowire Array Lithium Ion Anodes Stabilized by Electrolyte Additives.

    Science.gov (United States)

    Jackson, Everett D; Prieto, Amy L

    2016-11-09

    Nanowires of electrochemically active electrode materials for lithium ion batteries represent a unique system that allows for intensive investigations of surface phenomena. In particular, highly ordered nanowire arrays produced by electrodeposition into anodic aluminum oxide templates can lead to new insights into a material's electrochemical performance by providing a high-surface-area electrode with negligible volume expansion induced pulverization. Here we show that for the Li-Cu x Sb ternary system, stabilizing the surface chemistry is the most critical factor for promoting long electrode life. The resulting solid electrolyte interphase is analyzed using a mix of electron microscopy, X-ray photoelectron spectroscopy, and lithium ion battery half-cell testing to provide a better understanding of the importance of electrolyte composition on this multicomponent alloy anode material.

  4. High Lithium Insertion Voltage Single-Crystal H2 Ti12 O25 Nanorods as a High-Capacity and High-Rate Lithium-Ion Battery Anode Material.

    Science.gov (United States)

    Guo, Qiang; Chen, Li; Shan, Zizhao; Lee, Wee Siang Vincent; Xiao, Wen; Liu, Zhifang; Liang, Jingjing; Yang, Gaoli; Xue, Junmin

    2018-01-10

    H 2 Ti 12 O 25 holds great promise as a high-voltage anode material for advanced lithium-ion battery applications. To enhance its electrochemical performance, control of the crystal orientation and morphology is an effective way to cope with slow Li + -ion diffusion inside H 2 Ti 12 O 25 with severe anisotropy. In this report, Na 2 Ti 6 O 13 nanorods, prepared from Na 2 CO 3 and anatase TiO 2 in molten NaCl medium, were used as a precursor in the synthesis of long single-crystal H 2 Ti 12 O 25 nanorods with reactive facets. The as-prepared H 2 Ti 12 O 25 nanorods with a diameter of 100-200 nm showed higher charge (extraction) specific capacity and better rate performance than previously reported systems. The reversible capacity of H 2 Ti 12 O 25 was 219.8 mAh g -1 at 1C after 100 cycles, 172.1 mAh g -1 at 10C, and 144.4 mAh g -1 at 20C after 200 cycles; these values are higher than those of H 2 Ti 12 O 25 prepared by the conventional soft-chemical method. Moreover, the as-prepared H 2 Ti 12 O 25 nanorods exhibited superior cycle stability with more than 94 % retention of capacity with nearly 100 % coulombic efficiency after 100 cycles at 1C. On the basis of the above results, long single-crystal H 2 Ti 12 O 25 nanorods synthesized in molten NaCl with outstanding electrochemical characteristics hold a significant amount of promise for hybrid electric vehicles and energy-storage systems. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Effect of current pulses on Lithium intercalation batteries

    NARCIS (Netherlands)

    Jongh, de P.E.; Notten, P.H.L.

    2002-01-01

    The effect of (dis)charge pulses on lithium-ion batteries is evaluated using an electronic network model. Simulations give insight into the effect of the pulses on the internal processes such as diffusion, migration, electrochemical reactions, heat generation, etc. on time scales from microseconds

  6. A revolution in electrodes: recent progress in rechargeable lithium-sulfur batteries.

    Science.gov (United States)

    Fang, Xin; Peng, Huisheng

    2015-04-01

    As a promising candidate for future batteries, the lithium-sulfur battery is gaining increasing interest due to its high capacity and energy density. However, over the years, lithium-sulfur batteries have been plagued by fading capacities and the low Coulombic efficiency derived from its unique electrochemical behavior, which involves solid-liquid transition reactions. Moreover, lithium-sulfur batteries employ metallic lithium as the anode, which engenders safety vulnerability of the battery. The electrodes play a pivotal role in the performance of lithium-sulfur batteries. A leap forward in progress of lithium-sulfur batteries is always accompanied by a revolution in the electrode technology. In this review, recent progress in rechargeable lithium-sulfur batteries is summarized in accordance with the evolution of the electrodes, including the diversified cathode design and burgeoning metallic-lithium-free anodes. Although the way toward application has still many challenges associated, recent progress in lithium-sulfur battery technology still paints an encouraging picture of a revolution in rechargeable batteries. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Structure Interlacing and Pore Engineering of Zn2GeO4 Nanofibers for Achieving High Capacity and Rate Capability as an Anode Material of Lithium Ion Batteries.

    Science.gov (United States)

    Wang, Wei; Qin, Jinwen; Cao, Minhua

    2016-01-20

    An interlaced Zn2GeO4 nanofiber network with continuous and interpenetrated mesoporous structure was prepared using a facile electrospinning method followed by a thermal treatment. The mesoporous structure in Zn2GeO4 nanofibers is directly in situ constructed by the decomposition of polyvinylpyrolidone (PVP), while the interlaced nanofiber network is achieved by the mutual fusion of the junctions between nanofibers in higher calcination temperatures. When used as an anode material in lithium ion batteries (LIBs), it exhibits superior lithium storage performance in terms of specific capacity, cycling stability, and rate capability. The pore engineering and the interlaced network structure are believed to be responsible for the excellent lithium storage performance. The pore structure allows for easy diffusion of electrolyte, shortens the pathway of Li(+) transport, and alleviates large volume variation during repeated Li(+) extraction/insertion. Moreover, the interlaced network structure can provide continuous electron/ion pathways and effectively accommodate the strain induced by the volume change during the electrochemical reaction, thus maintaining structural stability and mechanical integrity of electrode materials during lithiation/delithiation process. This strategy in current work offers a new perspective in designing high-performance electrodes for LIBs.

  8. High-capacity electrode materials for electrochemical energy storage

    Indian Academy of Sciences (India)

    2015-06-02

    Jun 2, 2015 ... We discuss the role of nanoscale effects on the electrochemical ..... tems and BASF for developing high energy density lithium ion cells for plug-in electric ..... SEM and STEM images showing typical shapes and sizes of FeF2 ...

  9. Optimization of the lithium/thionyl chloride battery

    Science.gov (United States)

    White, Ralph E.

    1989-01-01

    A 1-D math model for the lithium/thionyl chloride primary cell is used in conjunction with a parameter estimation technique in order to estimate the electro-kinetic parameters of this electrochemical system. The electro-kinetic parameters include the anodic transfer coefficient and exchange current density of the lithium oxidation, alpha sub a,1 and i sub o,i,ref, the cathodic transfer coefficient and the effective exchange current density of the thionyl chloride reduction, alpha sub c,2 and a sup o i sub o,2,ref, and a morphology parameter, Xi. The parameter estimation is performed on simulated data first in order to gain confidence in the method. Data, reported in the literature, for a high rate discharge of an experimental lithium/thionyl chloride cell is used for an analysis.

  10. Synthesis and electrochemical performances of ZnO/MnO2 sea urchin-like sleeve array as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Fang, J.; Yuan, Y.F.; Wang, L.K.; Ni, H.L.; Zhu, H.L.; Yang, J.L.; Gui, J.S.; Chen, Y.B.; Guo, S.Y.

    2013-01-01

    MnO 2 is electrodeposited onto ZnO nanorod array grown on Ni foil, forming a binder-free ZnO/MnO 2 composited electrode. XRD, EDS, SEM and TEM are used to analyze the phase and microstructure of this composite. Burr-like MnO 2 nanoflakes grows on ZnO nanorod array, the top of the composite is hollow and at the bottom exists ZnO large block core as an internal support, forming ZnO/MnO 2 sea urchin-like sleeve array. As anode material for lithium ion batteries, ZnO/MnO 2 sleeve array exhibits higher discharge capacity and coulombic efficiency, better rate performance and cycling stability than single ZnO nanorod array or directly electrodepsited MnO 2 , and the composite effect is very remarkable. After 100 cycles, the discharge capacity of ZnO/MnO 2 still reaches 1259 mA h g −1 , and coulombic efficiency surpasses 98%, higher than those of ZnO nanorod array (111 mA h g −1 ) and directly electrodeposited MnO 2 (507 mA h g −1 ). The improvement of the electrochemical performances is due to the unique sea urchin-like sleeve array architecture. MnO 2 burr tube shell structure leads to high electrochemical activity while the internal ZnO core support ensures good structure stability. The gradually opening of sea urchin-like sleeve during the cycling further enhances the electrochemical activity of MnO 2 , stabilizing and increasing electrochemical performances of the ZnO/MnO 2 composite

  11. MATHEMATICAL MODELING OF ELECTROCHEMICAL PROCESSES IN LITHIUM-ION BATTERIES POTENTIALLY STREAMING METHOD

    Directory of Open Access Journals (Sweden)

    S. P. Halutin

    2014-01-01

    Full Text Available Mathematical models in the electrical parameters of physico-chemical processes in lithium-ion batteries are developed. The developed model parameters (discharge mode are identified out of family of discharging curve. By using of the parameters of this model we get the numerically model of lithium-ion battery.

  12. Preparation and electrochemical performance of copper foam-supported amorphous silicon thin films for rechargeable lithium-ion batteries

    International Nuclear Information System (INIS)

    Li Haixia; Cheng Fangyi; Zhu Zhiqiang; Bai Hongmei; Tao Zhanliang; Chen Jun

    2011-01-01

    Research highlights: → Amorphous Si thin films have been deposited on copper foam substrate by radio-frequency (rf) magnetron sputtering. → The as-prepared Si/Cu films with interconnected 3-dimensional structure are employed as anode materials of rechargeable lithium-ion batteries, showing that the electrode properties are greatly affected by the deposition temperature. → The film electrode deposited at an optimum temperature of 300 deg. C delivers a specific capacity of ∼2900 mAh/g and a coulombic efficiency above 95% at charge/discharge current density of 0.2C after 30 cycles. → The Li + diffusion coefficiency in copper foam-supported Si thin films is determined to be 2.36 x 10 -9 cm 2 /s. → The combination of rf magnetron sputtering and cooper foam substrate is an efficient route to prepare amorphous Si films with high capacity and cyclability due to the efficient ionic diffusion and interface contact with a good conductive current collector. - Abstract: Amorphous Si thin films, which have been deposited on copper foam by radio-frequency (rf) magnetron sputtering, are employed as anode materials of rechargeable lithium-ion batteries. The morphologies and structures of the as-prepared Si thin films are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray powder diffraction (XRD). Electrochemical performance of lithium-ion batteries with the as-prepared Si films as the anode materials is investigated by cyclic voltammetry and charge-discharge measurements. The results show that the electrode properties of the prepared amorphous Si films are greatly affected by the deposition temperature. The film electrode deposited at an optimum temperature of 300 deg. C can deliver a specific capacity of ∼2900 mAh/g and a coulombic efficiency above 95% at charge/discharge current density of 0.2C after 30 cycles. The Li + diffusion coefficiency in copper foam-supported Si thin films is determined to be 2.36 x 10 -9 cm

  13. About the safety of lithium batteries with carbon anode; De la securite des accumulateurs au lithium a anode de carbone

    Energy Technology Data Exchange (ETDEWEB)

    Biensan, Ph.; Le Nay, F. [SAFT, Direction de la Recherche, 91 - Marcoussis (France); Simon, B. [Alcatel Alsthom Recherche, 91 - Marcoussis (France); Bodet, J.M. [SAFT, Advanced and Industrial Battery Group, 86 - Poitiers (France)

    1996-12-31

    The replacement of lithium metal from the negative electrode of lithium batteries by a material allowing the reversible insertion of lithium ions is an undeniable commercial success. Carbon electrodes, generally called Li{sub x}C{sub 6}, are the most common type and allow to increase the service life of the battery, its charging fastness and its safety. The safety of such batteries is well known in normal conditions of use, but it has to be known also in any abusive condition of use, whatever is the charging state. The mastery of the phenomena that can occur requires a good knowledge of the kinetics of the exothermal chemical reactions involved. (J.S.) 8 refs.

  14. About the safety of lithium batteries with carbon anode; De la securite des accumulateurs au lithium a anode de carbone

    Energy Technology Data Exchange (ETDEWEB)

    Biensan, Ph; Le Nay, F [SAFT, Direction de la Recherche, 91 - Marcoussis (France); Simon, B [Alcatel Alsthom Recherche, 91 - Marcoussis (France); Bodet, J M [SAFT, Advanced and Industrial Battery Group, 86 - Poitiers (France)

    1997-12-31

    The replacement of lithium metal from the negative electrode of lithium batteries by a material allowing the reversible insertion of lithium ions is an undeniable commercial success. Carbon electrodes, generally called Li{sub x}C{sub 6}, are the most common type and allow to increase the service life of the battery, its charging fastness and its safety. The safety of such batteries is well known in normal conditions of use, but it has to be known also in any abusive condition of use, whatever is the charging state. The mastery of the phenomena that can occur requires a good knowledge of the kinetics of the exothermal chemical reactions involved. (J.S.) 8 refs.

  15. Interphase Evolution of a Lithium-Ion/Oxygen Battery.

    Science.gov (United States)

    Elia, Giuseppe Antonio; Bresser, Dominic; Reiter, Jakub; Oberhumer, Philipp; Sun, Yang-Kook; Scrosati, Bruno; Passerini, Stefano; Hassoun, Jusef

    2015-10-14

    A novel lithium-ion/oxygen battery employing Pyr14TFSI-LiTFSI as the electrolyte and nanostructured LixSn-C as the anode is reported. The remarkable energy content of the oxygen cathode, the replacement of the lithium metal anode by a nanostructured stable lithium-alloying composite, and the concomitant use of nonflammable ionic liquid-based electrolyte result in a new and intrinsically safer energy storage system. The lithium-ion/oxygen battery delivers a stable capacity of 500 mAh g(-1) at a working voltage of 2.4 V with a low charge-discharge polarization. However, further characterization of this new system by electrochemical impedance spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy reveals the progressive decrease of the battery working voltage, because of the crossover of oxygen through the electrolyte and its direct reaction with the LixSn-C anode.

  16. Improving the Electrochemical Performance of LiNi0.80Co0.15Al0.05O2 in Lithium Ion Batteries by LiAlO2 Surface Modification

    Directory of Open Access Journals (Sweden)

    Chunhua Song

    2018-03-01

    Full Text Available LiNi0.80Co0.15Al0.05O2 (NCA as a lithium ion battery cathode material has received attention for its highly specific capacity and excellent low temperature performance. However, the disadvantages of its high surface lithium compound residues and high pH value have influenced its processing performance and limited its application. This paper uses a facile method to modify NCA through LiAlO2 coating. The results showed that when the molar ratio of Al(NO33·9H2O and lithium compound residues at the surface of NCA cathode material was 0.25:1, the pH of the cathode material decreased from 12.70 to 11.80 and the surface lithium compound residues decreased from 3.99% to 1.48%. The NCA cell was charged and discharged for 100 cycles at 1 C in the voltage range of 3.0–4.3 V, to test the capacity retention of NCA. It was found to be as high as 94.67%, which was 5.36% higher than the control NCA cell. The discharge capacity of NCA-0.25-500 °C was 139.8 mAh/g even at 8 C rate, which was 15% higher than the raw NCA. Further research indicated that Al(NO33·9H2O reacted with the surface lithium compound residues of NCA and generated LiAlO2, which improved the NCA electrochemical performance.

  17. Battery Relevant Electrochemistry of Ag7Fe3(P2O7)4 : Contrasting Contributions from the Redox Chemistries of Ag+ and Fe3+

    International Nuclear Information System (INIS)

    Zhang, Yiman; Marschilok, Amy C.; Stony Brook University, NY; Takeuchi, Esther S.

    2016-01-01

    Ag 7 Fe 3 (P 2 O 7 ) 4 is an example of an electrochemical displacement material which contains two different electrochemically active metal cations, where one cation (Ag + ) forms metallic silver nanoparticles external to the crystals of Ag 7 Fe 3 (P 2 O 7 ) 4 via an electrochemical reduction displacement reaction, while the other cation (Fe +3 ) is electrochemically reduced with the retention of iron cations within the anion structural framework concomitant with lithium insertion. These contrasting redox chemistries within one pure cathode material enable high rate capability and reversibility when Ag 7 Fe 3 (P 2 O 7 ) 4 is employed as cathode material in a lithium ion battery (LIB). Further, pyrophosphate materials are thermally and electrically stable, desirable attributes for cathode materials in LIBs. In this article, a bimetallic pyrophosphate material Ag 7 Fe 3 (P 2 O 7 ) 4 is synthesized and confirmed to be a single phase by Rietveld refinement. Electrochemistry of Ag 7 Fe 3 (P 2 O 7 ) 4 is reported for the first time in the context of lithium based batteries using cyclic voltammetry and galvanostatic discharge–charge cycling. The reduction displacement reaction and the lithium (de)insertion processes are investigated using ex situ X-ray absorption spectroscopy and X-ray diffraction of electrochemically reduced and oxidized Ag 7 Fe 3 (P 2 O 7 ) 4 . Ag 7 Fe 3 (P 2 O 7 ) 4 exhibits good reversibility at the iron centers indicated by ~80% capacity retention over 100 cycles following the initial formation cycle and excellent rate capability exhibited by ~70% capacity retention upon a 4-fold increase in current.

  18. Study of the electrochemical behavior at low temperatures of green anodes for Lithium ion batteries prepared with anatase TiO2 and water soluble sodium carboxymethyl cellulose binder

    International Nuclear Information System (INIS)

    Mancini, M.; Nobili, F.; Tossici, R.; Marassi, R.

    2012-01-01

    Highlights: ► Water soluble CMC and PVDF binders are used to prepare anatase TiO 2 electrodes. ► The electrochemical behavior of the different electrodes is studied between 20 and −30 °C. ► CMC/TiO 2 anodes show lower ICL, lower polarization and higher low-temperature capacity at high rates than PVDF/TiO 2 anodes. ► Electrochemical Impedance Spectroscopy results show better kinetics for CMC/TiO 2 electrodes. - Abstract: The electrochemical behavior at low temperatures of anatase TiO 2 electrodes for Lithium ion batteries have been evaluated by galvanostatic cycles in the temperature range 20 to −30 °C. Two different manufacturing processes have been used to prepare anatase anodes containing water soluble sodium carboxymethyl cellulose (CMC) or poly(vinilydene fluoride) (PVDF) as binder. The low temperature performances at different charge/discharge rates of TiO 2 /CMC and TiO 2 /PVDF electrodes are compared and discussed in terms of irreversible capacity loss (ICL) at the first cycle, capacity retention and reversible capacity. The kinetics of the electrodes containing CMC or PVDF is evaluated by Electrochemical Impedance Spectroscopy.

  19. Amorphous boron nanorod as an anode material for lithium-ion batteries at room temperature.

    Science.gov (United States)

    Deng, Changjian; Lau, Miu Lun; Barkholtz, Heather M; Xu, Haiping; Parrish, Riley; Xu, Meiyue Olivia; Xu, Tao; Liu, Yuzi; Wang, Hao; Connell, Justin G; Smith, Kassiopeia A; Xiong, Hui

    2017-08-03

    We report an amorphous boron nanorod anode material for lithium-ion batteries prepared through smelting non-toxic boron oxide in liquid lithium. Boron in theory can provide capacity as high as 3099 mA h g -1 by alloying with Li to form B 4 Li 5 . However, experimental studies of the boron anode have been rarely reported for room temperature lithium-ion batteries. Among the reported studies the electrochemical activity and cycling performance of the bulk crystalline boron anode material are poor at room temperature. In this work, we utilized an amorphous nanostructured one-dimensional (1D) boron material aiming at improving the electrochemical reactivity between boron and lithium ions at room temperature. The amorphous boron nanorod anode exhibited, at room temperature, a reversible capacity of 170 mA h g -1 at a current rate of 10 mA g -1 between 0.01 and 2 V. The anode also demonstrated good rate capability and cycling stability. The lithium storage mechanism was investigated by both sweep voltammetry measurements and galvanostatic intermittent titration techniques (GITTs). The sweep voltammetric analysis suggested that the contributions from lithium ion diffusion into boron and the capacitive process to the overall lithium charge storage are 57% and 43%, respectively. The results from GITT indicated that the discharge capacity at higher potentials (>∼0.2 V vs. Li/Li + ) could be ascribed to a capacitive process and at lower potentials (ions and the amorphous boron nanorod. This work provides new insights into designing nanostructured boron materials for lithium-ion batteries.

  20. Synthesis, characterization and electrochemical performance of Li 2 ...

    Indian Academy of Sciences (India)

    Positive electrodes; lithium metal silicates; electrical conductivity; cyclic performance ... Furthermore, electrochemical impedance spectra measurements are performed ... It was observed that Li–Li 2 Ni 0.4 Fe 0.6 SiO 4 battery has initial discharge ... Central Metallurgical Research and Development Institute (CMRDI), Tebbin, ...

  1. Electrochemical potentials of layered oxide and olivine phosphate ...

    Indian Academy of Sciences (India)

    Lithium ion battery; cathodes; density functional theory; density of states; Bader charge analysis; electrochemical ... voltage, ionic diffusion coefficient, phase stability and charge ... routes to synthesis and fabrication techniques. .... from the lithiated one. ..... Ebner W, Fouchard D and Xie L 1994 Solid State Ionics 69 238.

  2. Effect of sulfolane on the performance of lithium bis(oxalato)borate-based electrolytes for advanced lithium ion batteries

    International Nuclear Information System (INIS)

    Li Shiyou; Zhao Yangyu; Shi Xinming; Li Bucheng; Xu Xiaoli; Zhao Wei; Cui Xiaoling

    2012-01-01

    Highlights: ► High purity of LiBOB is obtained by the compressing dry granulation method. ► LiBOB-SL/DEC electrolyte is an excellent candidate electrolyte for lithium ion batteries. ► It shows high oxidation potentials (>5.3 V) and satisfactory conductivities. ► In Li/MCMB cells, this novel electrolyte exhibits excellent film-forming characteristics and low impedances of the interface films. ► In LiFePO 4 /Li cells, this novel electrolyte exhibits stable cycle performance and high discharge voltage plateau (>3.35 V). - Abstract: Lithium bis(oxalato)borate (LiBOB) is a promising salt for lithium ion batteries. However, before applying in lithium ion batteries, it is necessary to prepare high purity LiBOB with a simple method, and find more appropriate solvent systems to exert the perfect electrochemical performance of LiBOB. In this paper, LiBOB is synthesized by the compressing dry granulation method, with the yield of 97%. Moreover, the electrochemical performances of LiBOB-sulfolane (SL)/diethyl carbonate (DEC) electrolyte are investigated. It shows high oxidation potentials (>5.3 V) and satisfactory conductivities, also the temperature dependence of the conductivity is well in accord with the Vogel–Tamman–Fulcher (VTF) behavior. When used in Li/MCMB (mesophase carbon microbeads) cells, this novel electrolyte exhibits not only excellent film-forming characteristics, but also low impedances of the interface films. When used in LiFePO 4 /Li cells, compared to the cell with the electrolyte system of LiBOB-EC/DEC electrolyte, LiBOB-SL/DEC electrolyte exhibit several advantages, such as more stable cycle performance, and higher discharge voltage plateau (>3.35 V).

  3. NbSe{sub 3} nanobelts wrapped by reduced graphene oxide for lithium ion battery with enhanced electrochemical performance

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jing; Sun, Qi; Wang, Zhijie; Xiang, Junxiang; Zhao, Benliang [Department of Materials Science & Engineering, CAS Key Lab of Materials for Energy Conversion, Synergetic Innovation Center of Quantum Information Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); Qu, Yan [The Sixth Element Materials Technology Co. Ltd, Changzhou, Jiangsu, 213145 (China); Xiang, Bin, E-mail: binxiang@ustc.edu.cn [Department of Materials Science & Engineering, CAS Key Lab of Materials for Energy Conversion, Synergetic Innovation Center of Quantum Information Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2017-08-01

    Highlights: • A core-shell structure of NbSe{sub 3} nanobelts wrapped by rGO is synthesized by a PDDA assisted method. • Cushion effect of the rGO coating enhances the structure integrity. • Performance of the composites during cycling are improved remarkably compared to the pure nanobelts. - Abstract: Recently, layered transition metal chalcogenides (LTMCs) have attracted great attention as anode materials for lithium ion batteries (LIBs). However, the volume expansion and structure instability of LTMCs during the lithiation and delithiation process still remains challenging. Herein, we report NbSe{sub 3} nanobelts wrapped by reduced-graphene oxide (NbSe{sub 3}@rGO) utilized as buffer layers with enhanced electrochemical performance. The X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy were used to probe features of the NbSe{sub 3}@rGO. The NbSe{sub 3}@rGO nanobelts as anode exhibit a discharge capacity of 300 mAh/g at the current density of 100 mAh/g after 250 cycles, several times higher than pure NbSe{sub 3} nanobelts. The improved electrochemical performance of NbSe{sub 3}@rGO is attributed to a buffer effect from the rGO, cushioning the volume-change-induced strain effect on the structure of NbSe{sub 3} nanobelts during cycling.

  4. A novel molten-salt electrochemical cell for investigating the reduction of uranium dioxide to uranium metal by lithium using in situ synchrotron radiation.

    Science.gov (United States)

    Brown, Leon D; Abdulaziz, Rema; Jervis, Rhodri; Bharath, Vidal; Mason, Thomas J; Atwood, Robert C; Reinhard, Christina; Connor, Leigh D; Inman, Douglas; Brett, Daniel J L; Shearing, Paul R

    2017-03-01

    A novel electrochemical cell has been designed and built to allow for in situ energy-dispersive X-ray diffraction measurements to be made during reduction of UO 2 to U metal in LiCl-KCl at 500°C. The electrochemical cell contains a recessed well at the bottom of the cell into which the working electrode sits, reducing the beam path for the X-rays through the molten-salt and maximizing the signal-to-noise ratio from the sample. Lithium metal was electrodeposited onto the UO 2 working electrode by exposing the working electrode to more negative potentials than the Li deposition potential of the LiCl-KCl eutectic electrolyte. The Li metal acts as a reducing agent for the chemical reduction of UO 2 to U, which appears to proceed to completion. All phases were fitted using Le Bail refinement. The cell is expected to be widely applicable to many studies involving molten-salt systems.

  5. Electrochemical cell assembled in discharged state

    Science.gov (United States)

    Yao, Neng-Ping; Walsh, William J.

    1976-01-01

    A secondary, electrochemical cell is assembled in a completely discharged state within a sealed containment. As assembled, the cell includes a positive electrode separated from a negative electrode by a molten salt electrolyte. The positive electrode is contained within a porous structure, permitting passage of molten electrolyte, and includes one or more layers of a metallic mesh, e.g. iron, impregnated with an intimate mixture of lithium sulfide and the electrolyte. The negative electrode is a porous plaque of aluminum metal. Prior to using the cell, an electrical charge forms lithium-aluminum alloy within the negative electrode and metal sulfide within the positive electrode.

  6. Lithium storage into carbonaceous materials obtained from sugarcane bagasse

    International Nuclear Information System (INIS)

    Matsubara, Elaine Y.; Lala, Stella M.; Rosolen, Jose Mauricio

    2010-01-01

    Carbonaceous materials with different structures are prepared by carbonization of sugarcane bagasse. Depending on carbonization conditions, it is possible to obtain soot rich in flakes or in honeycomb-shaped micrometric particles, whose concentration has large influence on lithium storage into electrodes. The soot rich in honeycomb-shaped particles provides the best electrochemical performance, with a reversible specific capacity of 310 mAh g -1 . The results suggest that the sugarcane bagasse can be potentially used in the design of anodic materials for lithium ion batteries. (author)

  7. In situ electrochemical creation of cobalt oxide nanosheets with favorable performance as a high tap density anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Lin, Qian; Sha, Yujing; Zhao, Bote; Chen, Yubo; Tadé, Moses O.; Shao, Zongping

    2015-01-01

    Highlights: • Cobalt oxide nanosheets in situ electrochemical generated from commercial LiCoO_2. • TEM indicates creation of cobalt oxide nanosheets from coarse layered LiCoO_2_. • Coarse-type LiCoO_2 with high tap density shows promising anode performance. • Optimizing weight ratio of LiCoO_2 in electrode, a high capacity was achieved. - Abstract: Cobalt oxides are attractive alternative anode materials for next-generation lithium-ion batteries (LIBs). To improve the performance of conversion-type anode materials such as cobalt oxides, well dispersed and nanosized particulate morphology is typically required. In this study, we describe the in situ electrochemical generation of cobalt oxide nanosheets from commercial micrometer-sized LiCoO_2 oxide as an anode material for LIBs. The electrode material as prepared was analyzed by XRD, FE-SEM and TEM. The electrochemical properties were investigated by cyclic voltammetry and by a constant current galvanostatic discharge–charge test. The material shows a high tap density and promising anode performance in terms of capacity, rate performance and cycling stability. A capacity of 560 mA h g"−"1 is still achieved at a current density of 1000 mA g"−"1 by increasing the amount of additives in the electrode to 40 wt%. This paper provides a new technique for developing a high-performance conversion-type anode for LIBs.

  8. Metalized, three-dimensional structured oxygen cathode materials for lithium/air batteries and method for making and using the same

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Weibing; Buettner-Garrett, Josh

    2017-04-18

    This disclosure relates generally to cathode materials for electrochemical energy cells, more particularly to metal/air electrochemical energy cell cathode materials containing silver vanadium oxide and methods of making and using the same. The metal/air electrochemical energy cell can be a lithium/air electrochemical energy cell. Moreover the silver vanadium oxide can be a catalyst for one or more of oxidation and reduction processes of the electrochemical energy cell.

  9. Hierarchically structured lithium titanate for ultrafast charging in long-life high capacity batteries

    Science.gov (United States)

    Odziomek, Mateusz; Chaput, Frédéric; Rutkowska, Anna; Świerczek, Konrad; Olszewska, Danuta; Sitarz, Maciej; Lerouge, Frédéric; Parola, Stephane

    2017-05-01

    High-performance Li-ion batteries require materials with well-designed and controlled structures on nanometre and micrometre scales. Electrochemical properties can be enhanced by reducing crystallite size and by manipulating structure and morphology. Here we show a method for preparing hierarchically structured Li4Ti5O12 yielding nano- and microstructure well-suited for use in lithium-ion batteries. Scalable glycothermal synthesis yields well-crystallized primary 4-8 nm nanoparticles, assembled into porous secondary particles. X-ray photoelectron spectroscopy reveals presence of Ti+4 only; combined with chemical analysis showing lithium deficiency, this suggests oxygen non-stoichiometry. Electron microscopy confirms hierarchical morphology of the obtained material. Extended cycling tests in half cells demonstrates capacity of 170 mAh g-1 and no sign of capacity fading after 1,000 cycles at 50C rate (charging completed in 72 s). The particular combination of nanostructure, microstructure and non-stoichiometry for the prepared lithium titanate is believed to underlie the observed electrochemical performance of material.

  10. Ionic Liquid-Doped Gel Polymer Electrolyte for Flexible Lithium-Ion Polymer Batteries

    Directory of Open Access Journals (Sweden)

    Ruisi Zhang

    2015-05-01

    Full Text Available Application of gel polymer electrolytes (GPE in lithium-ion polymer batteries can address many shortcomings associated with liquid electrolyte lithium-ion batteries. Due to their physical structure, GPEs exhibit lower ion conductivity compared to their liquid counterparts. In this work, we have investigated and report improved ion conductivity in GPEs doped with ionic liquid. Samples containing ionic liquid at a variety of volume percentages (vol % were characterized for their electrochemical and ionic properties. It is concluded that excess ionic liquid can damage internal structure of the batteries and result in unwanted electrochemical reactions; however, samples containing 40–50 vol % ionic liquid exhibit superior ionic properties and lower internal resistance compared to those containing less or more ionic liquids.

  11. Improved electrochemical performance of Li1.2Mn0.54Ni0.13Co0.13O2 cathode material synthesized by citric acid assisted sol-gel method for lithium ion batteries

    Science.gov (United States)

    Li, Shiyou; Liang, Youwei; Lei, Dan; Xie, Yingchun; Ai, Ling; Xie, Jing

    2018-03-01

    A citric acid assisted sol-gel method is employed for synthesizing Li1.2Mn0.54Ni0.13Co0.13O2 used as a cathode material in lithium-ion batteries. Powder X-ray diffraction (XRD) and scanning electron microscopy (SEM) characterizations prove that materials have a typical a-NaFeO2 structure with primary nano-sized particles. Electrochemical performances have been investigated by charge-discharge test and results show that the synthesized product exhibits excellent electrochemical performance with a high initial discharge capacity of 253.5 mAh g-1 at 0.1 C and a preferable capacity retention of 84.8% after 50 cycles.

  12. Metal-organic frameworks for lithium ion batteries and supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Ke, Fu-Sheng; Wu, Yu-Shan; Deng, Hexiang, E-mail: hdeng@whu.edu.cn

    2015-03-15

    Porous materials have been widely used in batteries and supercapacitors attribute to their large internal surface area (usually 100–1000 m{sup 2} g{sup −1}) and porosity that can favor the electrochemical reaction, interfacial charge transport, and provide short diffusion paths for ions. As a new type of porous crystalline materials, metal-organic frameworks (MOFs) have received huge attention in the past decade due to their unique properties, i.e. huge surface area (up to 7000 m{sup 2} g{sup −1}), high porosity, low density, controllable structure and tunable pore size. A wide range of applications including gas separation, storage, catalysis, and drug delivery benefit from the recent fast development of MOFs. However, their potential in electrochemical energy storage has not been fully revealed. Herein, the present mini review appraises recent and significant development of MOFs and MOF-derived materials for rechargeable lithium ion batteries and supercapacitors, to give a glimpse into these potential applications of MOFs. - Graphical abstract: MOFs with large surface area and high porosity can offer more reaction sites and charge carriers diffusion path. Thus MOFs are used as cathode, anode, electrolyte, matrix and precursor materials for lithium ion battery, and also as electrode and precursor materials for supercapacitors. - Highlights: • MOFs have potential in electrochemical area due to their high porosity and diversity. • We summarized and compared works on MOFs for lithium ion battery and supercapacitor. • We pointed out critical challenges and provided possible solutions for future study.

  13. Chemical insertion in the perovskite solid solutions Pr{sub 0.5+x-y}Li{sub 0.5-3x}Bi{sub y}{open_square}{sub 2x}TiO{sub 3}: Implications on the electrical properties

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Sanchez, M.F., E-mail: rusonil@yahoo.com [Unidad Profesional Interdisciplinaria en Ingenieria y Tecnologias Avanzadas-Instituto Politecnico Nacional (IPN), C.P. 07340, Mexico D.F. (Mexico); Fernandez, N. [Departamento de Quimica Inorganica, Universidad de la Habana, 10400 Ciudad de la Habana (Cuba); Martinez-Sarrion, M.-L.; Mestres, L. [Departament de Quimica Inorganica, Universitat de Barcelona, Marti i Franques 1-11, 08028 Barcelona (Spain); Santana, G. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, Ciudad Universitaria, Coyoacan 04510, Mexico D.F. (Mexico); Lewis, D.W. [Department of Chemistry, University College London, 20 Gordon St., London WC1H 0AJ (United Kingdom); Ruiz-Salvador, A.R. [Instituto de Ciencia y Tecnologia de Materiales, Universidad de La Habana, 10400 Ciudad de la Habana (Cuba)

    2012-05-15

    Highlight: Black-Right-Pointing-Pointer Lithium insertion is related to the number of vacancies and bismuth concentration. Black-Right-Pointing-Pointer The use of Kramers-Kronig relations allows the separation of the electronic conductivities. Black-Right-Pointing-Pointer The insertion changes the samples from ionic conductors to mixed conductors. Black-Right-Pointing-Pointer Electronic conduction is via a polaron mechanism with activation energy of {approx}0.8 eV. - Abstract: Chemical insertion and de-insertion of lithium in pellet samples of the solid solutions Pr{sub 0.5+x-y}Li{sub 0.5-3x}Bi{sub y}{open_square}{sub 2x}TiO{sub 3} were studied. Two regions of the phase diagram are studied: one having constant composition of bismuth and the other of lithium. The amount of inserted lithium depends on both the number of vacancies and the amount of bismuth in the original samples. The conductivity of the samples is directly related to the amount of inserted lithium and the activation energy depends on the unit cell volume. An analysis of the electronic and ionic components of the conductivity reveals that the untreated materials are pure ionic conductors, while after Li-insertion an additional electronic conductivity (t < 10{sup -2}) occurs, due to a polaron mechanism, with an activation energy of 0.8 eV.

  14. Battery of circular cell shape with central lithium anode and non-aqueous electrolytes. Galvanisches Element in Rundzellenform mit zentrisch angeordneter Lithium-Anode und nichtwaessrigem Elektrolyten

    Energy Technology Data Exchange (ETDEWEB)

    Kretzschmar, R

    1987-06-11

    The separation of such a cell situated between the negative and positive electrode is formed by a loose plastic vliess cut into a strip, which during assembly of the cells, is laid with central orientation on the open cell cup already provided with a circular cathode and filled with electrolyte and is pressed directly through the bar-shaped lithium electrode into the hollow space of the annular cathode, where it surrounds the lithium electrode as a compressed, closed sheath. Excess electrolyte flows into the sheath from the uncompressed top part of the separator vliess over the electrodes, to the extent that the lithium electrode is electrochemically dissolved and the expanding vliess maintaining contact with the lithium takes up liquid so that there is no interruption of ion conduction between the electrodes.

  15. Chemical Immobilization Effect on Lithium Polysulfides for Lithium-Sulfur Batteries.

    Science.gov (United States)

    Li, Caixia; Xi, Zhucong; Guo, Dexiang; Chen, Xiangju; Yin, Longwei

    2018-01-01

    Despite great progress in lithium-sulfur batteries (LSBs), great obstacles still exist to achieve high loading content of sulfur and avoid the loss of active materials due to the dissolution of the intermediate polysulfide products in the electrolyte. Relationships between the intrinsic properties of nanostructured hosts and electrochemical performance of LSBs, especially, the chemical interaction effects on immobilizing polysulfides for LSB cathodes, are discussed in this Review. Moreover, the principle of rational microstructure design for LSB cathode materials with strong chemical interaction adsorbent effects on polysulfides, such as metallic compounds, metal particles, organic polymers, and heteroatom-doped carbon, is mainly described. According to the chemical immobilizing mechanism of polysulfide on LSB cathodes, three kinds of chemical immobilizing effects, including the strong chemical affinity between polar host and polar polysulfides, the chemical bonding effect between sulfur and the special function groups/atoms, and the catalytic effect on electrochemical reaction kinetics, are thoroughly reviewed. To improve the electrochemical performance and long cycling life-cycle stability of LSBs, possible solutions and strategies with respect to the rational design of the microstructure of LSB cathodes are comprehensively analyzed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Long life lithium batteries with stabilized electrodes

    Science.gov (United States)

    Amine, Khalil [Downers Grove, IL; Liu, Jun [Naperville, IL; Vissers, Donald R [Naperville, IL; Lu, Wenquan [Darien, IL

    2009-03-24

    The present invention relates to non-aqueous electrolytes having electrode stabilizing additives, stabilized electrodes, and electrochemical devices containing the same. Thus the present invention provides electrolytes containing an alkali metal salt, a polar aprotic solvent, and an electrode stabilizing additive. In some embodiments the additives include a substituted or unsubstituted cyclic or spirocyclic hydrocarbon containing at least one oxygen atom and at least one alkenyl or alkynyl group. When used in electrochemical devices with, e.g., lithium manganese oxide spinel electrodes or olivine or carbon-coated olivine electrodes, the new electrolytes provide batteries with improved calendar and cycle life.

  17. High-Performance Lithium-Oxygen Battery Electrolyte Derived from Optimum Combination of Solvent and Lithium Salt.

    Science.gov (United States)

    Ahn, Su Mi; Suk, Jungdon; Kim, Do Youb; Kang, Yongku; Kim, Hwan Kyu; Kim, Dong Wook

    2017-10-01

    To fabricate a sustainable lithium-oxygen (Li-O 2 ) battery, it is crucial to identify an optimum electrolyte. Herein, it is found that tetramethylene sulfone (TMS) and lithium nitrate (LiNO 3 ) form the optimum electrolyte, which greatly reduces the overpotential at charge, exhibits superior oxygen efficiency, and allows stable cycling for 100 cycles. Linear sweep voltammetry (LSV) and differential electrochemical mass spectrometry (DEMS) analyses reveal that neat TMS is stable to oxidative decomposition and exhibit good compatibility with a lithium metal. But, when TMS is combined with typical lithium salts, its performance is far from satisfactory. However, the TMS electrolyte containing LiNO 3 exhibits a very low overpotential, which minimizes the side reactions and shows high oxygen efficiency. LSV-DEMS study confirms that the TMS-LiNO 3 electrolyte efficiently produces NO 2 - , which initiates a redox shuttle reaction. Interestingly, this NO 2 - /NO 2 redox reaction derived from the LiNO 3 salt is not very effective in solvents other than TMS. Compared with other common Li-O 2 solvents, TMS seems optimum solvent for the efficient use of LiNO 3 salt. Good compatibility with lithium metal, high dielectric constant, and low donicity of TMS are considered to be highly favorable to an efficient NO 2 - /NO 2 redox reaction, which results in a high-performance Li-O 2 battery.

  18. Electrochemical investigation of electrochromic devices based on NiO and WO3 films using different lithium salts electrolytes

    International Nuclear Information System (INIS)

    Wei, Youxiu; Chen, Mu; Liu, Weiming; Li, Lei; Yan, Yue

    2017-01-01

    Highlights: •ECDs based on NiO and WO 3 films using different electrolytes were fabricated. •Effect of different electrolytes on films and ECDs was investigated. •Applied voltage distribution on NiO and WO 3 electrodes in an ECD was studied. •Voltage distribution on films was unbalanced and associated with electrolyte. •Films have different impedance behavior in different states and electrolytes. -- Abstract: Electrochromic devices (ECDs) with different liquid electrolytes were fabricated using NiO film as counter electrode, WO 3 film as working electrode. The effect of liquid electrolytes containing different lithium salts (LiClO 4 , LiPF 6 , LiTFSI) on films and ECDs was investigated, such as transmittance change, charge density, memory effect and cyclic stability. Films or ECDs using LiPF 6 electrolyte have excellent electrochromic properties but low cyclic stability, compared with LiClO 4 and LiTFSI electrolytes. In order to deeply understand the effect of electrolyte on films and devices, the voltage distribution of films based on an analog cell and electrochemical impedance spectroscopy (EIS) were measured and analyzed in different lithium salts electrolytes. Results show that voltage distribution and EIS characteristics of films have obvious difference in liquid LiClO 4 , LiPF 6 and LiTFSI electrolytes. Voltage distribution on NiO and WO 3 films is unbalanced and the impedance of films in bleached and colored states is different in the same electrolyte.

  19. Lithium superionic conductor Li9.42Si1.02P2.1S9.96O2.04 with Li10GeP2S12-type structure in the Li2S–P2S5–SiO2 pseudoternary system: Synthesis, electrochemical properties, and structure–composition relationships

    Directory of Open Access Journals (Sweden)

    Satoshi Hori

    2016-12-01

    Full Text Available Lithium superionic conductors with the Li10GeP2S12 (LGPS-type structure are promising materials for use as solid electrolytes in next-generation lithium batteries. A novel member of the LGPS family, Li9.42Si1.02P2.1S9.96O2.04, and its solid solutions were synthesised by quenching from 1273 K in the Li2S–P2S5–SiO2 pseudoternary system. The material exhibited an ionic conductivity as high as 3.2×10−4 S cm−1 at 298 K, as well as the high electrochemical stability to lithium metal, which was improved by the introduction of oxygen into the LGPS-type structure. An all-solid-state cell with a lithium metal anode and Li9.42Si1.02P2.1S9.96O2.04 as the separator showed excellent performance with a high coulomb efficiency of 100%. Thus, oxygen doping is an effective way of improving the electrochemical stability of LGPS-type structure.

  20. In situ synthesis of Co{sub 3}O{sub 4}/graphene nanocomposite material for lithium-ion batteries and supercapacitors with high capacity and supercapacitance

    Energy Technology Data Exchange (ETDEWEB)

    Wang Bei, E-mail: Bei.Wang-1@student.uts.edu.au [School of Chemistry and Forensic Science, University of Technology Sydney, City Campus, Broadway, Sydney, NSW 2007 (Australia); Wang Ying [School of Chemistry and Forensic Science, University of Technology Sydney, City Campus, Broadway, Sydney, NSW 2007 (Australia); Park, Jinsoo; Ahn, Hyojun [School of Materials Science and Engineering, Gyeongsang National University, 900 Gazwa-dong Jinju, Gyeongnam 660-701 (Korea, Republic of); Wang Guoxiu, E-mail: Guoxiu.Wang@uts.edu.au [School of Chemistry and Forensic Science, University of Technology Sydney, City Campus, Broadway, Sydney, NSW 2007 (Australia)

    2011-07-21

    Highlights: > In situ solution-based preparation of Co{sub 3}O{sub 4}/graphene composite material. > Well dispersed Co{sub 3}O{sub 4} nanoparticles on graphene nanosheets. > Co{sub 3}O{sub 4}/graphene exhibits highly reversible lithium storage capacity. > Co{sub 3}O{sub 4}/graphene delivers superior supercapacitance up to 478 F g{sup -1}. > Functional groups make contributions to the overall supercapacitance. - Abstract: Co{sub 3}O{sub 4}/graphene nanocomposite material was prepared by an in situ solution-based method under reflux conditions. In this reaction progress, Co{sup 2+} salts were converted to Co{sub 3}O{sub 4} nanoparticles which were simultaneously inserted into the graphene layers, upon the reduction of graphite oxide to graphene. The prepared material consists of uniform Co{sub 3}O{sub 4} nanoparticles (15-25 nm), which are well dispersed on the surfaces of graphene nanosheets. This has been confirmed through observations by field emission scanning electron microscopy, transmission electron microscopy and atomic force microscopy. The prepared composite material exhibits an initial reversible lithium storage capacity of 722 mAh g{sup -1} in lithium-ion cells and a specific supercapacitance of 478 F g{sup -1} in 2 M KOH electrolyte for supercapacitors, which were higher than that of the previously reported pure graphene nanosheets and Co{sub 3}O{sub 4} nanoparticles. Co{sub 3}O{sub 4}/graphene nanocomposite material demonstrated an excellent electrochemical performance as an anode material for reversible lithium storage in lithium ion cells and as an electrode material in supercapacitors.