以TiCl4水溶液和LiOH·H2O为原料,采用原位水解与后续热处理相结合的方法制备尖晶石型锂离子电池用负极材料Li4Ti5O12。结果表明:从TiCl4水溶液原位水解合成Li4Ti5O12经历由TiCl4→TiO2→Li2TiO3→Li4Ti5O123个阶段的原位相转变过程;TiCl4水溶液的浓度及稳定性对合成Li4Ti5O12的结构有较大的影响;随着TiCl4浓度的增加,合成纯Li4Ti5O12所需的水解时间延长;以0.5mol/LTiCl4水溶液水解1h、以添加1.0mol/LLiCl的0.5mol/LTiCl4水溶液水解3h、以1.0mol/L与1.5mol/LTiCl水溶液水解5h均可获得纯Li4Ti5O12由低浓度TiCl4水溶液合成的Li4Ti5O12循环性能优良。
Spinel Li4Ti5O12 as an anode material for lithium ion batteries was synthesized via in-situ hydrolysis followed by heat treatment using aqueous TICl4 solution and LiOH-H20 as the raw materials. The results show that the synthesis of Li4Ti5O12 from aqueous TiCl4 solution by in-situ hydrolysis consists of three-step in-situ phase transformation, that is TiCl4→TiO2→Li2TiO3→LinTi5O12. The concentration and stability of aqueous TiCl4 solution have significant effects on the synthesis of Li4Ti5O12. With increasing TiCl4 concentration, the hydrolysis time of TiCl4 for the formation of Li4Ti5O12 increases. The optimal hydrolysis time for the synthesis of pure Li4Ti5O12 from TiCl4 solutions with different Ti(Ⅳ) concentrations is found to be 1 h for 0.5 mol/L TiCl4, 3 h for 0.5 mol/L TiCl4 with addition of 1.0 mol/L LiCl and 5 h for both 1.0 mol/L and 1,5 mol/L TICl4. The products prepared from lower Ti(Ⅳ) concentration solutions show excellent cycling performance.