Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2/Ag电极材料的制备及电化学性能  

Preparation and Electrochemical Performance of Li(Ni_(1/3)Co_(1/3)Mn_(1/3))O_2/Ag Electrode Material

作　　者：曾姝[1] 刘建本[1,2] 麦发任[1] 粟四水[1] 

机构地区：[1]吉首大学化学化工学院,湖南吉首416000 [2]湘西自治州矿产与新材料技术创新服务中心,湖南吉首416000

出　　处：《热加工工艺》2012年第22期66-69,72,共5页Hot Working Technology

基　　金：吉首大学大学生研究性学习和创新性实验计划基金资助项目(2011ZX JJ22)

摘　　要：以碳酸盐为沉淀剂,采用共沉淀法合成晶型良好的亚微米级Li(Ni1/3Co1/3Mn1/3)O2粉末,并将其与AgNO3复合,采用无电流分解沉积法制备出了Ag表面修饰的Li(Ni1/3Co1/3Mn1/3)O2/Ag电极材料。利用X-射线衍射、扫描电镜及电化学测试等方法表征材料的结构、形貌和电化学性能。结果表明:Ag单质的存在可明显改善Li(Ni1/3Co1/3Mn1/3)O2的电化学性能,尤其是倍率特性,以0.2C、0.5C、1C倍率放电进行测试,经过40次循环后比容量分别为156.2、144.3、137.7mAh.g-1,其容量保持率分别为96.2%、95.3%、93.9%。Ag的表面修饰能使Li(Ni1/3Co1/3Mn1/3)O2电荷转移阻抗大幅度减小,阻抗从65Ω减小到50Ω。The submicron Li （Ni1/3C01/3Mn1/3）O2 powders with high crystallinity were prepared by co-precipitation method using carbonate as the precipitant. Silver nitrate was employed in the preparation ofLi （Ni1/3C01/3Mn1/3）O2/Ag composite by an electroless deposition method. The microstructure, morphology and electrochemical performance of the composite were characterized by X-ray diffxactometry, scanning electron microscopy and electrochemical techniques. The results indicate that the presence of Ag is favorable to the electrochemical performances ofLi （Ni1/3C01/3Mn1/3）O2, particularly high rate performance. After 40 cycles at a discharge rate of 0.2C, 0.5C and 1C, the discharge capacity is 156.20, 144.29 and 137.68 mAh ·g-1, respectively, which is corresponded to capacity retention of 96.2%, 95.3% and 93.9%. The Ag coating on the surface of Li （Ni1/3C01/3Mn1/3）O2 particle can decrease its charge transfer impedance from 6512 to 50 12.

关 键 词：锂离子电池 LI(NI1/3CO1/3MN1/3)O2 表面修饰 银 共沉淀法 无电流分解沉积法 

分 类 号：TG113.224[金属学及工艺—物理冶金]