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Journal of the Chilean Chemical Society , 2010, DOI: 10.4067/S0717-97072010000200029
Abstract: we have determined the electrochemical behavior of a series of long chain 1-alkyl-3-methylimidazolium ionic liquids [(r-mim)bf4], with alkyl groups ranging from pentyl to octyl, and tested them as electrolytes in lithium ion batteries. these ionic liquids present good conductivities and electrochemical windows which make them likely solvents of choice for li-ion batteries using limn2o4 as the cathode. charge/discharge properties of a li/ r-mim)bf4/limn2o4 cell have been evaluated both with the il as the sole electro lyte and with il and conducting support. the li- ion insertion results in il can be explained on the basis of self aggregation of each long chain 1-alkyl-3-methylimidazolium cation.
Journal of the Chilean Chemical Society , 2010,
Abstract: We have determined the electrochemical behavior of a series of long chain 1-alkyl-3-methylimidazolium ionic liquids [(R-mim)BF4], with alkyl groups ranging from pentyl to octyl, and tested them as electrolytes in lithium ion batteries. These ionic liquids present good conductivities and electrochemical Windows which make them likely solvents of choice for Li-ion batteries using LiMn2O4 as the cathode. Charge/discharge properties of a Li/ R-mim)BF4/LiMn2O4 cell have been evaluated both with the IL as the sole electro lyte and with IL and conducting support. The Li- ion insertion results in IL can be explained on the basis of self aggregation of each long chain 1-alkyl-3-methylimidazolium cation.
Progression of the silicate cathode materials used in lithium ion batteries
LiYing Bao,Wei Gao,YueFeng Su,Zhao Wang,Ning Li,Shi Chen,Feng Wu
Chinese Science Bulletin , 2013, DOI: 10.1007/s11434-012-5583-3
Abstract: Poly anionic silicate materials, which demonstrate a high theoretical capacity, high security, environmental friendliness and low-cost, are considered one of the most promising candidates for use as cathode materials in the next generation of lithium-ion batteries. This paper summarizes the structure and performance characteristics of these materials. The effects of different synthesis methods and calcination temperature on the properties of these materials are reviewed. Materials that demonstrate low conductivity, poor stability, cationic disorder or other drawbacks, and the use of various modification techniques, such as carbon-coating or compositing, elemental doping and combination with mesoporous materials, are evaluated as well. In addition, further research topics and the possibility of using these kinds of cathode materials in lithium-ion batteries are discussed.
Sulfurized Carbon: A Class of Cathode Materials for High Performance Lithium/Sulfur Batteries  [PDF]
Sheng S. Zhang
Frontiers in Energy Research , 2013, DOI: 10.3389/fenrg.2013.00010
Abstract: Liquid electrolyte lithium/sulfur (Li/S) batteries cannot come into practical applications because of many problems such as low energy efficiency, short cycle life, and fast self-discharge. All these problems are related to the dissolution of lithium polysulfide, a series of sulfur reduction intermediates, in the liquid electrolyte, and resulting parasitic reactions with the Li anode. Covalently binding sulfur onto carbon surface is a solution to completely eliminate the dissolution of lithium polysulfide and make the Li/S battery viable for practical applications. This can be achieved by replacing elemental sulfur with sulfurized carbon (SC) as the cathode material. This article reviews the current efforts on this subject and discusses the syntheses, electrochemical properties, and prospects of the SC as a cathode material in the rechargeable Li/S batteries.
Triple-Cation-Doped Li3V2(PO4)3 Cathode Material for Lithium Ion Batteries

- , 2015, DOI: 10.3866/PKU.WHXB201506082
Abstract: 以柠檬酸为螯合剂和还原剂, NH4VO3为钒源,通过溶胶-凝胶法制备了锂离子电池正极材料Li3V2(PO4)3及其三元掺杂体系Li2.85Na0.15V1.9Al0.1(PO4)2.9F0.1.分别采用X射线衍射(XRD)、高分辨透射电子显微镜(HRTEM)、能量损失谱(EELS)、拉曼(Raman)光谱、扫描电子显微镜(SEM)、X射线能谱(EDS)、恒流充放电、循环伏安(CV)和交流阻抗谱(EIS)等技术对材料的微观结构、颗粒形貌和电化学性能进行分析.结果表明:在残余碳包覆的基础上, Na、Al、F三元掺杂有利于稳定Li3V2(PO4)3的晶体结构,进一步减少颗粒团聚和提升材料导电特性,促进第三个锂离子的脱出和嵌入,从而显著改善Li3V2(PO4)3的实用电化学性能.未经掺杂的Li3V2(PO4)3原粉在1/9C、1C和6C倍率下的可逆比容量分别为141、119和98 mAh·g-1,而三元掺杂改性材料在1/9C、1C、8C和14C倍率下的比容量分别为172、139、119和115 mAh·g-1.在1C倍率下循环300圈后,掺杂体系的比容量依然高达118 mAh·g-1,比原粉高出32.6%.值得注意的是,这种三元掺杂还使Li3V2(PO4)3的多平台放电曲线近似转变为一条斜线,显示出可能不同的储锂机制.
Li3V2(PO4)3 and its triple-cation-doped counterpart Li2.85Na0.15V1.9Al0.1(PO4)2.9F0.1 were prepared by a conventional sol-gel method. The effect of Na-Al-F co-doping on the physicochemical properties, especially the electrochemical performance of Li3V2(PO4)3, were investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), electron energy loss spectroscopy (EELS), Raman spectroscopy, scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS), galvanostatic charge/discharge, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). It was found that combined with surface coating from residual carbon, this triple-cation co-doping stabilizes the crystalline structure of Li3V2(PO4)3, suppresses secondary particle agglomeration, and improves the electric conductivity. Moreover, reversible deinsertion/insertion of the third lithium ion at deeper charge/discharge is enabled by such doping. As a consequence, the practical electrochemical performance of Li3V2(PO4)3 is significantly improved. The specific capacity of the doped material at a low rate of 1/9C is 172 mAh·g-1 and it maintains 115 mAh·g-1 at a rate of 14C, while the specific capacities of the undoped sample at 1/9C and 6C are only 141 and 98 mAh·g-1, respectively. After 300 cycles at 1C rate, the doped material has a capacity of 118 mAh·g-1, which is 32.6% higher than that of the undoped counterpart. It is also noteworthy that the multiplateau discharge curve of Li3V2(PO4)3 transforms to a slope-like curve, indicating the possibility of a different lithium intercalation mechanism after this co-doping
Thermal Stability of Nickel-based Lithium Transition Metal Oxides as the Cathode Materials for Lithium-ion Batteries

YUAN Rong-Zhong,QU Mei-Zhen,YU Zuo-Long,

无机材料学报 , 2003,
Abstract: Lithium nickel oxide as the positive electrode of rechargeable lithium ion batteries with a high energy density and lower cost has aroused more and more interests. However, LiNiO2 has a few disadvantages which prevent this material from being used as a cathode material for rechargeable lithium ion batteries. Poor thermal stability is one of its major disadvantages. In this paper, the progress in recent researches on the thermal behavior of full-lithiated, electrochemically delithiated Li1_xNi02 and the thermal decomposition mechanism were reviewed, and the studies for developing nickel-based lithium transition metal oxides with improved thermal stability as cathode materials were summarized.


物理学报 , 1985,
Abstract: The structure of amorphous MoS3 as the cathode materials in lithium batteries was studied by using X-ray diffraction method and X-ray photoelectron spectroscopy. The results revealed that the structure of amorphous MoS3 is built by homogeneously eandomly stacking of the MoS2 basic unit S-Mo-S sand wich layvs and the amorphous sulphus chains Sn.
Development of Vanadium Oxide in Lithium Ion Batteries

CHEN Chang-Guo,LIU Yu-Ping,LI Lan,

无机材料学报 , 2004,
Abstract: The development of vanadium oxides in lithium ion batteries was summaried. The structure, synthesis methods, electrochemical performances of V2O5, V6O13, VO2, V3O7 and V6O14 in lithium ion batteries were reviewed. The reasons for V4O9, V2O3 excluded from the application in lithium ion batteries were explained. Then the advantage and problem of vanadium oxides as cathode materials of lithium ion batteries were pointed out. Finally the authors considered that those vanadium oxides could be promising as cathode materials of lithium ion batteries.
Composite cathode and anode films for rechargeable lithium batteries
Dihua Guan,Li Jiang,Wei Zhou,Guoquan Yang,Gang Wang,Sishen Xie
Chinese Science Bulletin , 1998, DOI: 10.1007/BF02883925
Abstract: Recently the rechargeable Li and Li-ion polymer batteries have improved due to development of Li-ion conductive gel electrolytes and of high energe granting intercalation compounds. In our laboratory the composite cathodic film, the composite carbon anode film and PVC-based electralyte film were successfully prepared by casting procedures. Cycling experiments of the cells with Li or composite carbon anode in contact with PVC-based electrolyte and composite cathode were performed. Relatively good performance of the cell with Li anode, the composite cathode and LiPF6-EC-DEC electrolyte was achieved in that over 50 cycles were possible with minimal capacity loss upon cycling. The same cell with PVC-based electrolyte was cycled over 20 cycles. Replacing Li anode by composite carbon anode, the cell behaved like the latter. It is found that appropriate amount of carbon content is helpful to improving specific capacity.
Research and Development of Preparing Spherical Cathode Materials for Lithium Ion Batteries by Controlled Crystallization Method

YING Jie-Rong,GAO Jian,JIANG Chang-Yin,WAN Chun-Rong,HE Xiang-Ming,

无机材料学报 , 2006,
Abstract: The spherical cathode materials for lithium ion batteries have the outstanding advantages such as high pile-density, high capacity density and excellent manufacturing performance, being expected as the important directions. The "controlled crystallization" method is an ideal way to prepare spherical cathode materials. This paper introduced the principle of "controlled crystallization" method and reviewed the research and development of the spherical cathode materials, including LiCoO2, LiNi0.8Co0.2O2, LiMn2O4, LiNi1/3Co1/3Mn1/3O2, and LiFePO4. The prospective application of the spherical cathode materials was also analyzed.
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