(中南大学 冶金科学与工程学院，长沙 410083)
摘 要: 以金红石型TiO2、Li2CO3和Al2O3为原料，采用高温固相法制备锂离子电池负极材料Li4Ti5O12和Li4AlxTi5-xO12(x=0, 0.025, 0.05, 0.1, 0.2, 0.4)。利用X射线衍射仪、扫描电镜、半电池充放电测试和交流阻抗测试研究材料的物相、结构、形貌以及电化学性能。结果表明：Al掺杂不会改变Li4AlxTi5-xO12的尖晶石结构，但会导致材料颗粒尺寸增大；适当Al掺杂后，材料的循环稳定性和极化性能得到改善，充放电比容量和可逆比容量不同程度降低；Li4Al0.025Ti4.975O12具有最优的电化学性能，0.1C倍率下首次充电比容量达到156.7 mA·h/g。
关键字: 钛酸锂；锂离子电池；负极材料；Al掺杂
eletrochemical performance of Li4Ti5O12
（School of Metallurgical Science and Engineering, Central South University, Changsha 410083, China）
Abstract:Anode materials Li4Ti5O12 and Li4AlxTi5−xO12(x=0, 0.025, 0.05, 0.1, 0.2, 0.4) were prepared by solid-state reaction using rutile TiO2 and Li2CO3 as the reactants. The crystalline structure, morphology, composition and electrochemical properties of the as-prepared materials were characterized by XRD, SEM and half cell charge-discharge testing and AC impedance. The results show that all of the prepared Li4AlxTi5−xO12 keep the structure of spinel, however, the particle size of samples with Al-doping increases in a certain extent and the appropriate amount of Al doping in Li4Ti5O12 leads to obvious decrease in initial and the reversible specific capacity, but improves the cycling stability and electrochemical polarization. In this study, Li4Al0.025Ti4.975O12 shows the best electrochemical performance and delivers the first discharge specific capacity of 156.7mA·h/g at 0.1 C.
Key words: lithium titanate; Li-ion battery; anode material; Al-doping
