溶胶凝胶法制备Li_4Ti_5O_(12)/C负极材料及电化学性能

采用溶胶凝胶法,以有机物钛酸四丁酯和醋酸锂为原料,草酸为螯合剂,PEG为碳源制备出Li_4Ti_5O_(12)/C复合材料前驱体,在N_2气氛中850℃高温煅烧制备出Li_4Ti_5O_(12)/C复合材料。通过XRD、SEM分析表明,850℃下煅烧10 h合成结晶性良好的亚微米级纯相尖晶石钛酸锂。电化学性能测试结果表明,Li_4Ti_5O_(12)/C在0.2C,1C,2C倍率下的首次放电比容量分别为173.3、168.7、166.3 mAh/g。与Li_4Ti_5O_(12)相比,显示出良好的倍率性。

Synthesis of Li4Ti5O12/C anode material by sol-gel method and its electrochemical properties

Li4Ti5O12/C composite was prepared by sol-gel method,using Ti (OC4H9)4,LiCH3COO ·2H2O as raw materials,oxalic acid as chelating agent and PEG as carbon source to prepare the precursor.The structure and morphology of Li4Ti5O12/C composite were characterized by XRD and SEM method.Its electrochemical properties were measured by charge-discharge cycling text.It is found that the phase-pure and sub-micron Li4Ti5O12/C is obtained by sintering the precursor at 850 ℃ under N2 atomosphere.The prepared Li4Ti5O12/C presents a more excellent rate capability than Li4Ti5O12.The first discharge specific capacity of Li4Ti5O12/C reaches 173.3,168.7,166.3 mAh/g at 0.2C,1 C,2C,respectively.