富锂正极材料Li_(1+x)Ni_(0.5)Mn_(0.5)O_2的制备及电化学性能

Synthesis and eletrochemical performance of Li-rich cathode material Li_(1+x)Ni_(0.5)Mn_(0.5)O_2

通过液相沉淀法制备球形Ni（OH）2,与Mn（NO3）2和CH3COOLi·2 H2O混合,经高温固相法制备富锂Li1＋xNi0.5Mn0.5O2正极材料。采用X射线衍射（XRD）、扫描电镜（SEM）、电化学交流阻抗及恒流充放电测试对样品的结构、形貌和电化学性能进行表征。结果表明,当x=0.2时制备的富锂材料,阳离子混排低、颗粒均匀,表现出最好的电化学性能。在2.0∽4.8 V之间,20 m A/g条件下最高放电比容量为201.4 m Ah/g,60 m A/g下放电比容量仍可达到113.1m Ah/g。

Li1＋xNi0.5Mn0.5O2 Li-rich cathode material was CH3COOLi.2 H20 and the spherical Ni（OH）2 prepared by prepared through solid-state method with Mn （NO3）2, quid phase precipitation. XRD, SEM, AC impedance and constant current charge-discharge test were used to investigate structure, morphology and eletrochemical performance. The results indicate that the material ofLi1＋xNi0.5Mn0.5O2 （x=0.2） has the lowest cation mixing, uniform particle and the best electrochemical behavior. At the voltage rang of 2.0-4.8 V, the highest discharge specific capacity is 201.4 mAh/g at 20 mA/g. The discharge specific capacity is 113.1 mAh/g even at 60 mA/g.