( 1. 天津大学 化工学院 应用化学系， 天津 300072;
2. 天津力神电池股份有限公司， 天津 300384)
摘 要: 采用有机溶剂醇热法， 以异丙醇铝为原材料对LiCoO2进行表面处理。通过XRD、 SEM对包覆前后正极材料的微观结构进行表征， 对包覆前后正极材料的电化学性能进行测试。结果表明： 包覆后正极材料的充放电效率明显提高， 循环30次后容量保持率由包覆前的84.1%提高到包覆后的93.2%。 这归因于包覆后LiCoO2表面形成的Al2O3或LiAlxCo1-xO2层，该层起到阻挡层的作用， 有效地抑制Co4+与电解液反应，稳定了LiCoO2结构，提高了电化学循环性能。
关键字: 有机溶剂醇热法; 表面修饰; 循环性能; 充放电效率
（ 1. School of Chemical Engineering and Technology,
Tianjin University, Tianjin 300072, China;
2. Tianjin Lishen Battery Joint-Stock Co.Ltd,
Tianjin 300384, China）
Abstract: The organic solvent alcohol-heating method was used to modify LiCoO2 cathode material’s surface with aluminium isopropoxide. The structures of surface-modified LiCoO2 cathode material were characterized with X-ray diffraction(XRD) and scanning electron microscope(SEM).The electrochemical measurement results show that the charge/discharge efficiency of coated LiCoO2 is improved significantly and the capacity retention is increased from 84.1% to 93.2% after 30 cycle times. The improvements are attributed to the Al2O3 or solid solution LiAlxCo1-xO2 layer on the LiCoO2 surface. The coating layer is effective in stopping reactions of Co4+ ions with electrolyte, and stabilizes the structure of LiCoO2, so improving the electrochemical cycle performance.
Key words: organic solvent alcohol-heating method； surface-modification； cycle performance; charge/discharge efficiency
