LiNi_(0.5)Mn_(1.5)O_4正极材料制备及其电化学性能研究

Synthesis and electrochemical performance of LiNi_(0.5)Mn_(1.5)O_4 cathode materials

以二氧化锰、氧化镍和碳酸锂为原料,采用二次焙烧工艺制备了尖晶石型镍锰酸锂(LiNi0.5Mn1.5O4)正极材料。采用X射线衍射(XRD)、扫描电镜(SEM)、交流阻抗测试(EIS)和充放电测试对LiNi0.5Mn1.5O4正极材料进行了表征。结果表明,合成的材料晶体结构完整,形貌规则,并且表现出优异的电化学性能,其0.2 C首次放电容量为134.6 mA·h/g,5 C首次放电容量为112.9 mA·h/g,5 C循环34次后容量保持率为103.3%。

Spinel-type LiNi0.5Mn1.5O4 cathode materials were synthesized by twice-calcination method using MnO2, NiO, and Li2CO3 as raw materials.The samples were characterized by X-ray diffraction （XRD）,scanning electron microscope （SEM）, electrochemical impedance spectroscopy （EIS）,and charge-discharge test.Results showed that the samples presented the perfect crystal structure and the regular morphology,which also showed excellent electrochemical performance ,the fist discharge capacity reached 134.6 mA. h/g at 0.2 C rates, 112.9 mA. h/g at 5 C rates, and the capacity retention after 34 cycles at 5 C was 103.3%.