水溶液体系中MgO表面修饰LiNi_(0.9)Co_(0.1)O_2的制备及性能研究

在水溶液体系中,采用化学沉淀法对镍基正极材料LiNi_(0.9)Co_(0.1)O_2进行了MgO表面修饰,研究了MgO修饰量对材料物理和化学性能的影响。采用SEM、XRD、电池测试仪、电化学工作站等研究了材料的物理和化学性能。结果表明,MgO修饰后,材料表面有许多MgO微小颗粒,pH降低,阳离子混排程度降低;当MgO修饰量为1%时有最佳的电化学性能,其首次充放电效率为83%,50周循环后容量保持率为90.7%。

Study on Preparation and Performance of MgO Surface Modified LiNi0.9Co0.1O2 in Aqueous Solution System

MgO surface modified nickel based cathode material LiNi0.9Co0.1O2 was prepared by chemical precipitation method in aqueous solution system to investigate effect of amount of MgO modification on physical and chemical properties of the material. The physical and chemical properties were tested by XRD, SEM, battery tester and electrochemical workstation. The results show that surface of the material have many MgO tiny particles after surface modification by MgO, and both pH value and degree of cationic mixing drop. Electrochemical performance is the best upon amount of MgO modification of 1%. Initial charge discharge efficiency is 83%, and capacity retention rate is 90.7% after 50 cycles.