物理化学学报 >> 2007, Vol. 23 >> Issue (Supp): 56-59.doi: 10.3866/PKU.WHXB2007Supp13

研究论文 上一篇    下一篇

非化学计量比的Li1+xCoO2正极材料的性能

江卫军; 赛喜雅勒图; 乌云毕力格; 其鲁; 商士波   

  1. 中信国安盟固利新能源科技有限公司, 北京 102200; 北京大学化学与分子工程学院应用化学系, 新能源材料与技术实验室, 北京 100871
  • 收稿日期:1900-01-01 修回日期:1900-01-01 发布日期:2008-01-04
  • 通讯作者: 其鲁 E-mail:qilu@pku.edu.cn

Performance of Nonstoichiometric Li1+xCoO2 Cathode Materials

JIANG Wei-Jun; Sai-Xi-Ya-Le-Tu; Wu-Yun-Bi-Li-Ge; QI Lu; SHANG Shi-Bo   

  1. CITIC Guoan Mengguli New Engery Technology Co. Ltd., Beijing 102200, P. R. China; New Energy Materials and Technology Laboratory, Department of Applied Chemistry, College of Chemical and Molecular Engineering, Peking University, Beijing 100871, P. R. China
  • Received:1900-01-01 Revised:1900-01-01 Published:2008-01-04
  • Contact: QI Lu E-mail:qilu@pku.edu.cn

摘要: 以不同的nLi/nCo比例合成LiCoO2和非化学计量比的Li1+xCoO2(x=0.02, 0.05)正极材料. 采用扫描电子显微镜(SEM)、X射线粉末衍射(XRD)、电感耦合等离子体鄄原子发射光谱(ICP-AES)、激光粒度分布、BET法和电化学等方法对生成物质进行了晶体结构、元素组成、物理性能和电化学性能等分析. 结果表明, 过量的碳酸锂能改变生成物质的表面形貌、增大粒径、降低比表面积和提高密度. 同时, 过量的Li 元素能抑制不利的相转变, 提高物质的结构稳定性, 50次循环的平均衰减率从1.9‰降低到1.3‰.

关键词: 锂离子二次电池, 正极材料, LiCoO2, 非化学计量比

Abstract: LiCoO2 and nonstoichiometric Li1+xCoO2(x=0.02, 0.05) cathode materials were synthesized under various nLi/nCo ratio. X-rayDiffraction (XRD), scanning electronic microscope (SEM), inductively coupled plasma-atomic emission spectrometry (ICP-AES), laser particle size distribution, BET and electrochemical analysis were used to characterize the materials. The results showed that excess Li2CO3 added could smooth particles’surface, enlarge particles’size, reduce particles’ specific surface area and increase materials’density. The results of electrochemical analysis also indicated that excess Li in LiCoO2 could suppress the disadvantageous crystal phase change, stabilize materials’ structure and decrease the average loss ratio to 1.3‰ from 1.9‰ during 50 cycles.

Key words: Lithium-ion secondary batteries, Cathode materials, LiCoO2, Nonstoichiometry

MSC2000: 

  • O646