The cathode materials of spinel LiMn3O4 and LiCoxAl0.05Mn1.05-xO3.95(x=0,0.01) for lithium ion batteries were synthesized by sol-gel method. The crystalline structure of as-prepared cathode materials was characterized by XRD. The electrochemical performance of the materials was tested by constant-current cyclic testing and cyclic voltammogram. The results show that the materials possesses the pure spinel structure,LiCo0.01AI0.06Mn1.944O3.95F0.05 exhibits the best electrochemical performance with initial specific discharge capacity of 122.9 mAh/g and 120.8 mAh/g respectively in the room temperature (25 ℃) and the high temperature (55 ℃), and the capacity retention is 94.9% and 89.5% after 40 cycles, respectively. It is evident that the multiple doping can improve the stability of spinel structure and cycle performance.%采用溶胶-凝胶法合成了尖晶石型LiMn2O4和多元复合掺杂的LiCoxAl0.05Mn1.95-xO3.95F0.05(x=0,0.01)正极材料.通过X射线衍射(XRD)对材料的晶体结构进行了分析,通过恒电流充放电和循环伏安对材料的电化学性能进行了测试.实验结果表明:所制备的材料均具有良好的尖晶石结构,其中LiCo0.01Al0.05Mn1.94O3.95F0.05电化学性能最佳,在室温(25℃)和高温(55℃)下恒流充放电,首次放电比容量为122.9 mAh/g和120.8 mAh/g,循环40次后容量保持率高达94.9％和89.5％,充分说明复合掺杂能有效提高其结构稳定性和循环性能.
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