锂钒氧化物的液相法合成及电化学性能

Research on Liquid-state Reaction Synthesis and Electrochemical Property of Lithium Vanadium Oxide

采用液相法合成锂离子电池正极材料锂钒氧化物.通过XRD,TG-DTA分析确定了合成反应的主要历程.采用XRD及SEM、恒电流充放电、循环伏安测试研究了产物Li1+xV3O8的物理和电化学特征.结果表明,该法合成的产物为单一相层状结构,颗粒均匀,首次放电容量达288.9mA-h/g,15次后仍保持在264.0mA-h/g,容量保持率为91.38%,充放电效率在95%以上.Li+在Li1+xV3O8中的嵌入过程是分步进行的.

Lithium vanadium oxide was synthesized by a liquid-state reaction method. The main reaction mechanism was determined by XRD and TG-DTA analysis. Physical characteristics and electrochemical performances of Li1＋xV3O8 were investigated by XRD, SEM, galvanostatic charge-discharge and cyclic voltammogram tests. The results indicated that the as-synthesized material had pure layered structure and was evengranular. A maximum reversible capacity of 288.9 mA.b./g for the first cycle and 264.0 mA.b./g after 15 cycles were obtained and charge-discharge efficiency was above 93.84%. Insertion of Li^＋ in Li1＋xV3O8 proceeded step by step.