LiNi0.4Co0.2Mn0.4O2与LiMn2O4共混正极材料电化学性能

为开发具有优良循环性能和安全性能的大型锂离子电池的正极材料，将不同比例的LiNi0.4Co0.2Mn0.4O2和LiMn2O4材料进行共混，研究了LiNi0.4Co0.2Mn0.4O2和LiMn2O4共混以及共混比例(10∶0、8∶2、7∶3、6∶4、5∶5、0∶10)对锂离子电池的首次放电性能、循环性能和倍率性能以及交流阻抗和循环伏安曲线的影响，并采用扫描电镜对电极材料进行了表征.研究结果表明，共混比例会影响材料的电化学性能，8∶2，7∶3和6∶4配比的混合材料的体积比容量、循环性能和倍率性能要好于纯LiNi0.4Co0.2Mn0.4O2和LiMn2O4材料.其中，8∶2配比的材料性能最好.
In order to explore the positive material with excellent cycling ability and good safety, the effects of co-mixed ratios(10∶0、8∶2、7∶3、6∶4、5∶5、0∶10) of LiNi0.4Co0.2Mn0.4O2 with LiMn2O4 as the positive material of lithium ion battery on the first discharging properties, cycling abilities, rate capabilities, impedance spectroscopy and cyclic voltammetry were investigated. The co-mixed electrode materials were also characterized by SEM. The results indicated that the co-mixed ratio affected the electrochemical performances of the co-mixed materials. The materials with the ratios of 8∶2, 7∶3 and 6∶4 showed higher specific volumetric capacity, better cyclic and rate performances than that of LiNi0.4Co0.2Mn0.4O2 and LiMn2O4 materials. The co-mixed material with the ratio of 8∶2 is the best.