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›› 2007, Vol. 7 ›› Issue (4): 817-821.

• 材料工程专栏 • 上一篇    下一篇

层状锂离子电池正极材料LiNi0.8Co0.1Mn0.1O2的制备及性能

王希敏,王先友,易四勇,曹俊琪   

  1. 湘潭大学化学学院
  • 出版日期:2007-08-20 发布日期:2007-08-20

Synthesis and Characteristics of Layered LiNi0.8Co0.1Mn0.1O2 Cathode Material for Lithium Rechargeable Batteries

WANG Xi-min,WANG Xian-you,YI Si-yong,CAO Jun-qi   

  1. Department of Chemistry, Xiangtan University
  • Online:2007-08-20 Published:2007-08-20

摘要: 采用共沉淀法得到前驱体Ni0.8Co0.1Mn0.1(OH)2,利用前驱体与LiOH×H2O的高温固相反应得到高振实密度的锂离子电池层状正极材料LiNi0.8Co0.1Mn0.1O2 (2.3~2.5 g/cm3). 初步探讨了合成条件对材料电化学性能的影响. 通过X射线衍射(XRD)、扫描电镜(SEM)、热重-差热分析(TG/DTG)以及恒电流充放电测试对合成的样品进行了测试和表征. 结果表明,在750℃、氧气气氛下合成的材料具有较好的电化学性能. 通过XRD分析可知该材料为典型的六方晶系a-NaFeO2结构;SEM测试发现产物粒子是由500~800 nm的一次小晶粒堆积形成的二次类球形粒子. 电化学测试表明,其首次放电容量和库仑效率分别为168.6 mA×h/g和90.5%, 20次循环后容量为161.7 mA×h/g,保持率达到95.9%,是一种具有应用前景的新型锂离子电池正极材料.

关键词: 锂离子电池, 正极材料, 锂镍钴锰复合氧化物, 层状结构, 共沉淀法

Abstract: Layered LiNi0.8Co0.1Mn0.1O2 powder was synthesized by reacting quasi-spherical Ni0.8Co0.1Mn0.1(OH)2 prepared by co-precipitation with LiOH×H2O through high temperature sintering route. The obtained powder was characterized by X-ray diffraction (XRD), scanning electronic microscope (SEM), thermogravimetric-differential thermogravimetric analysis (TG-DTG) and constant current charge-discharge cycling. The results revealed that the optimal preparation condition of the layered LiNi0.8Co0.1Mn0.1O2 was 750℃ under oxygen flowing. The XRD pattern of the sample prepared under the above condition could be identified by a typical structure of hexagonal a-NaFeO2 type. The SEM micrograph of LiNi0.8Co0.1Mn0.1O2 showed that a large number of spherical primary particles with an average size of about 500~800 nm piled loosely to form quasi-spherical secondary particles. Electrochemical measurements showed that it delivered an initial discharge capacity of 168.6 mA×h/g during the first charge and discharge cycle, and the first coulombic efficiency was 90.5%, and the discharge capacity in the 20th cycle was 161.7 mA×h/g. The material would be potential cathode material for Li-ion battery.

Key words: lithium ion battery, cathode material, lithium nickel cobalt manganese oxide, layered structure, co-precipitation