摘要
本文讨论Y^(3+)掺杂对锂离子电池正极材料LiNi_(0.85)Co_(0.075)Mn_(0.075)O_(2)的影响.首先采用共沉淀法合成LiNi_(0.85)Co_(0.075)Mn_(0.075)(OH)_(2)前驱体,然后在一定的氧气气氛下,采用固态氧化法制备目标产物LiNi_(0.85)Co_(0.075)Mn_(0.075)O_(2)、Li(Ni_(0.85)Co_(0.075)Mn_(0.075))_(0.98)Y_(0.02)O_(2)正极材料.采用X射线衍射(X-ray diffraction,XRD)、扫描电子显微镜(scanning electron microscope,SEM)、恒流充放电、循环伏安法对材料的微观结构、颗粒形貌和电化学性能进行分析.结果表明,Y^(3+)的掺杂扩大了锂离子的扩散通道,抑制了样品与电解质之间的副反应,提高了样品的循环性能.在0.2C时,经过100次循环,掺杂样品的放电比容量为173 mAh·g^(-1),容量保持率为96.64%,电化学性能良好.
In this paper,the influence of Y^(3+)doping in cathode material LiNi_(0.85)Co_(0.075)Mn_(0.075)O_(2)of lithium-ion batteries was discussed.Firstly,the precursor LiNi_(0.85)Co_(0.075)Mn_(0.075)(OH)_(2)was synthesized by the co-precipitation method.And then the target products cathode materials LiNi_(0.85)Co_(0.075)Mn_(0.075)O_(2)and Li(Ni_(0.85)Co_(0.075)Mn_(0.075))_(0.98)Y_(0.02)O_(2)were synthesized by solid-state oxidation reaction in an oxygen atmosphere.X-ray diffraction(XRD),scanning electron microscope(SEM),constant current charge and discharge,cyclic voltammetry were used to analyze the microstructure,particle morphology and electrochemical properties of the materials.The results showed that Y^(3+)doping improved their cycling performance because it promoted the diffusion channel of Li+and inhibited the side reactions between samples and electrolytes.At 0.2C,after 100 cycles,the discharge specific capacity of the doped sample was 173 mAh·g^(-1),the capacity retention rate was 96.64%,and the electrochemical performance was good.
作者
刘丹
朱伟
朱小健
王礼
彭俊仁
LIU Dan;ZHU Wei;ZHU Xiaojian;WANG Li;PENG Junren(School of Chemistry and Chemical Engineering,Chongqing University,Chongqing 401331,China)
关键词
物理化学
锂离子电池
共沉淀法
富镍正极材料
钇离子掺杂
physical chemistry
lithium-ion batteries
co-precipitation method
nickel-rich cathode material
yttrium ion doping
