The LiNi0.5Co0.2Mn0.3O2/LiFePO4 blend cathode material for lithium-ion battery was prepared by wet ball-milling. The crystalline structure and morphology of the sample were characterized by X-ray diffraction(XRD) and scanning electron microscope(SEM),and the electrochemical performances of LiNi0.5Co0.2Mn0.3O2/LiFePO4 blend cathode material were investigated by galvanostatic charge/discharge, cyclic voltammetry(CV) and electrochemical impedance spectroscopy(EIS) tests. The results indicate that the crystalline structure of LiNi0.5Co0.2Mn0.3O2/LiFePO4 are preserved well, and the LiNi0.5Co0.2Mn0.3O2 is coated by LiFePO4 nanoparticals. Among all the composite cathodes, the one with 15% mass fraction of LiFePO4 shows the best electrochemical performance.The initial discharge specific capacity of battery is 181.40 mAh·g–1 at 0.2C rate,andthe first charge and discharge efficiency is 90.79%. Its discharge specific capacity is 169.89 mAh·g–1 after 50 cycles at 1.0 Crate, with capacity retention of 97.80%, and the discharge specific capacity is 162.22 mAh·g–1after 5 cycles at 3.0C rate,with capacity retention of 89.43%.After high temperature storaged for 7 days at 60℃, the capacity retention rate and capacity recovery rateare 86.48% and 97.32%,respectively.%采用湿法球磨制备了锂离子电池用混合正极材料LiNi0.5Co0.2Mn0.3O2/LiFePO4.通过X射线衍射(XRD)和扫描电镜(SEM)表征了材料的结构和形貌,采用恒流充放电测试、循环伏安测试(CV)和电化学阻抗谱测试(EIS)方法研究了混合正极材料LiNi0.5Co0.2Mn0.3O2/LiFePO4的电化学性能.结果表明:混合正极材料LiNi0.5Co0.2Mn0.3O2/LiFePO4的晶体结构完好,碳包覆的纳米LiFePO4颗粒较好地包覆在LiNi0.5Co0.2Mn0.3O2表面.含质量分数15%LiFePO4的混合正极材料LiNi0.5Co0.2Mn0.3O2/LiFePO4电化学性能优良,0.2C首次充放电比容量为181.40 mAh·g–1,首次充放电效率为90.79%;1.0C循环50次后放电比容量为169.89 mAh·g–1,容量保持率为97.80%;3.0C循环5次后的放电比容量为162.22 mAh·g–1,容量保持率仍有89.43%;60℃高温存储7d后,容量保持率和容量恢复率分别为86.48%和97.32%.
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