Li4Ti5O12的溶胶-凝胶合成及其电化学性能

摘要

The electrode material LiTi5O12 with excellent electrochemical properties was synthesized by a sol-gel method using lactic acid (LA) as chelating agent, tetrabutyl titanate and lithium acetate dihydrate as raw materials.The structure and electrochemical properties of Li4Ti5O12 samples were determined by thermogravimetry (TG), X-ray diffractometry (XRD), scanning electron microscopy (SEM), charge-discharge cycling and cyclic voitammogram (CV).The results indicate that Li4Ti5O12 synthesized at 800 ℃ for 18 h has fine crystallization, uniform particle distribution and good electrochemical performance.The initial discharge capacity is 184.32 mA·h/g, and the discharge capacity remains 155.62 mA·h/g after 50 charge-discharge cycles at 0.5 C rate.%以乳酸(LA)为配位剂,Ti(OC4H-H9)4和LiAc·2H2O为原料,通过溶胶-凝胶法制备具有优良电化学性能的电极材料Li4Ti5O12.采用热重分析(TG)、X射线衍射(XRD)、扫描电镜(SEM)、恒流充放电以及循环伏安(CV)等方法对合成的材料进行结构表征和电化学性能测试.结果表明:在800℃烧结18 h制备的样品颗粒分布均匀、结晶度良好、电化学性能优良.0.5 C倍率的首次放电比容量为184.32 mA·h/g,50次循环后仍然保持在155.62mA·h/g.