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以CH3COOLi·2H2O、Ni(CH3COO)2·4H2O、Co(CH3COO)2·4H2O和Mn(CH3COO)2·4H2O为原料,采用高温固相法制备正极材料LiNi1/3Co1/3Mn1/3O2。采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对材料的结构和形貌进行了表征,用恒电流充放电测试系统测试材料的电化学性能。结果表明:不同Li/(Ni+Co+Mn)摩尔比时制备的层状正极材料LiNi1/3Co1/3Mn1/3O2都具有典型的六方晶系α-NaFeO2型层状结构特征,晶型结构完整,颗粒大小在450~650nm之间。电化学性能结果表明:充放电电压为2.6~4.6V,电流密度为0.1C循环3次,0.2C循环20次,0.5C循环20次,在Li/(Ni+Co+Mn)摩尔比为1.1︰1时合成的正极材料的首次放电比容量为181.5mAh/g,43次后的放电比容量为161.5mAh/g,容量保持率为88.98%。
The cathode materials LiNi1 / 3Co1 / 3Mn1 / 3O2 were prepared by high temperature solid state reaction with CH3COOLi · 2H2O, Ni (CH3COO) 2.4H2O, Co (CH3COO) 2.4H2O and Mn (CH3COO) 2.4H2O as raw materials. The structure and morphology of the materials were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical properties of the materials were tested by a constant current charge-discharge test system. The results show that the layered LiNi1 / 3Co1 / 3Mn1 / 3O2 cathode materials prepared at different molar ratios of Li / (Ni + Co + Mn) have the typical hexagonal α-NaFeO2 layered structure with complete crystal structure, Particle size between 450 ~ 650nm. The results of electrochemical performance showed that the charge / discharge voltage was 2.6 ~ 4.6V, the current density was 0.1C for 3 cycles, 0.2C for 20 cycles and 0.5C for 20 cycles. When the molar ratio of Li / (Ni + Co + Mn) : 1, the initial discharge capacity of the synthesized cathode material was 181.5 mAh / g, the discharge capacity after 43 passes was 161.5 mAh / g, and the capacity retention rate was 88.98%.