TiO_(2)包覆对V_(2)O_(5)锂离子电池负极材料电化学性能的影响  

Effect of TiO_(2)Coating on Electrochemical Performance of V_(2)O_(5)Li-Ion Battery Anode Materials

作　　者：韦玉红 华骏[1] 彭商权 肖佳俊 章聪华 谭旭峰 颜文斌[1] WEI Yu-hong;HUA Jun;PENG Shang-quan;XIAO Jia-jun;ZHANG Cong-hua;TAN Xu-feng;YAN Wen-bin(College of Chemistry and Chemical Engineering,Jishou University,Jishou 416000,China)

机构地区：[1]吉首大学化学化工学院,湖南吉首416000

出　　处：《稀有金属与硬质合金》2023年第2期90-97,共8页Rare Metals and Cemented Carbides

摘　　要：以偏钒酸铵为V源,酞酸四丁酯为Ti源,通过水热反应和350℃焙烧制备微米级花球网络状V_(2)O_(5)@TiO_(2)复合材料。以V_(2)O_(5)@TiO_(2)复合材料作为锂离子电池负极材料,对其电化学性能进行了测试。结果表明,在恒流充放电电流密度为100 mA/g的条件下,循环300圈后,微粒级V_(2)O_(5)放电比容量为270 mA·h/g,同时容量保持率仅为50.2%;而在相同的测试条件下,V_(2)O_(5)@TiO_(2)复合材料放电比容量高达619.9 mA·h/g,容量保持率高达160.7%。V_(2)O_(5)@TiO_(2)复合材料能在长期循环过程中保持较高的放电比容量,主要归因于包覆的TiO_(2)起到了保护层的作用,抑制了V_(2)O_(5)在电解液中的溶解,且降低了Li+嵌入/脱出的应力,减缓了V_(2)O_(5)结构的退化。本研究结果为V_(2)O_(5)作为锂离子电池负极材料的制备和表面改性提供了一种简单有效的方法。Using ammonium metavanadate as V raw material and tetrabutyl phthalate as Ti raw material,micron-sized flower ball V_(2)O_(5)@TiO_(2)composites in network shape were prepared by hydrothermal reaction and calcination at 350℃.The electrochemical performance of V_(2)O_(5)@TiO_(2)composites as anode materials for lithium-ion batteries was tested.The results show that under the condition of constant current chargedischarge current density of 100 mA/g,the specific discharge capacity of particulate V_(2)O_(5)is 270 mA·h/g with a capacity retention rate of 50.2%after 300 cycles,while the specific discharge capacity of V_(2)O_(5)@TiO_(2)composites is as high as 619.9 mA·h/g with the capacity retention rate of 160.7%under the same test conditions.The ability of V_(2)O_(5)@TiO_(2)composites to maintain a high specific discharge capacity during long-term cycling is mainly attributed to the coating of TiO_(2)that acts as a protective layer,which inhibits the dissolution of V_(2)O_(5)in the electrolyte and reduces the stress of Li+insertion/extraction,slowing down the degradation of the V_(2)O_(5)structure.The results of this study provide a simple and effective method for the preparation and surface modification of V_(2)O_(5)as anode materials for lithium-ion batteries.

关 键 词：锂离子电池 V_(2)O_(5) TiO_(2)包覆 放电比容量 循环性能 

分 类 号：TB34[一般工业技术—材料科学与工程]