ZnO包覆LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2的表面结构和电化学性能  

Surface Structure and Electrochemical Performance of ZnO Coated LiNi_(1/3)Co_(1/3)Mn_(1/3)O_2

作　　者：刘昌位[1] 王宇[1] 郭玉忠[1] 淡露露 王剑华[2] 

机构地区：[1]昆明理工大学材料科学与工程学院,云南昆明650093 [2]昆明理工大学分析测试中心,云南昆明650093

出　　处：《电化学》2014年第1期60-65,共6页Journal of Electrochemistry

基　　金：昆明理工大学校基金项目(No.KKZ4200730010)资助

摘　　要：在LiNi1/3Co1/3Mn1/3O2正极材料表面包覆ZnO,通过X射线衍射(XRD)和光电子能谱(XPS)分析包覆层对正极材料表面状态的改变,并考察了改性后材料的放电容量、首次不可逆容量等电化学性能变化.结果表明:ZnO主要存在于材料表面并影响着材料表面组成和电化学性质,材料表面镍和锰的含量随着包覆量的增加而增大;400oC热处理可使过渡金属与锌在材料表面形成复合氧化物,过渡金属的结合能增大;包覆2%(by mass,下同)的ZnO可有效抑制55 oC下充放电时3.6 V附近的不可逆反应,提高了材料的首次库仑效率;包覆2%ZnO的电池材料在55oC/0.5C的放电比容量和循环寿命最佳.The surface of LiNit^COlcjMnl^O2 particles were modified by ZnO. Surface structure and electrochemical properties of the coated materials were investigated by X-ray diffraction （XRD）, X-ray photoelectron spectroscopy （XPS） and electrochemical tests, The results show that a ZnO coating affects the surface composition of LiNi1/3Co1/3eMn1/3O2 particles. The surface contents of nickel and manganese increase with the amount of ZnO coating. ZnO can react with LiNi1/3COl/3）Mn1/3O2 and a complex oxide is formed during the heat-treatment at above 400℃. The electrochemical studies suggest that a ZnO coating hinder the electrochemical reactions near 3.6 V for pristine sample. The initial columbic efficiency is significantly enhanced by coating LiNil/3Co1/3Mnl/3O2 with 2% （by mass） ZnO, which delivers high discharge capacity and shows excellent capacity retention at 55 ℃/0.5C.

关 键 词：LINI1 3Col 3Mn1 3O2 包覆 表面 锂离子电池 

分 类 号：TM912[电气工程—电力电子与电力传动]