物理化学学报 >> 2006, Vol. 22 >> Issue (07): 840-844.doi: 10.1016/S1872-1508(06)60037-5

研究论文 上一篇    下一篇

Nb 掺杂LiFePO4/C 的一步固相合成及电化学性能

庄大高;赵新兵;谢健;涂健;朱铁军;曹高劭   

  1. 浙江大学硅材料国家重点实验室, 杭州 310027
  • 收稿日期:2006-02-21 修回日期:2006-03-24 发布日期:2006-06-27
  • 通讯作者: 赵新兵 E-mail:zhaoxb@zju.edu.cn

One-step Solid-state Synthesis and Electrochemical Performance of Nb-doped LiFePO4/C

ZHUANG Da-Gao;ZHAO Xin-Bing;XIE Jian;TU Jian;ZHU Tie-Jun;CAO Gao-Shao   

  1. State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027, P. R. China
  • Received:2006-02-21 Revised:2006-03-24 Published:2006-06-27
  • Contact: ZHAO Xin-Bing E-mail:zhaoxb@zju.edu.cn

摘要: 用固相法一步合成了Nb掺杂的LiFePO4/C复合材料, 研究了Nb掺杂量对材料电化学性能的影响. 结果表明, Nb掺杂后LiFePO4/C复合材料的电化学性能明显提高. 在0.5C、1C和2C充放电倍率下, 名义成分为Li0.96Nb0.008FePO4/C正极材料的比容量分别为161、148和132 mAh•g−1, 已达到实用化水平. 阻抗谱和循环伏安特性测试显示, Nb掺杂有效地降低了复合材料电极的阻抗和极化, 说明Nb掺杂的主要作用是提高了LiFePO4的电子电导率.

关键词: 锂离子电池, 正极材料, Nb掺杂, LiFePO4/C, 电化学性能

Abstract: Nb-doped LiFePO4/C was synthesized using one-step solid-state method. The effect of Nb contents on the electrochemical performance was investigated. The results showed that the electrochemical performances were remarkably promoted. The discharge capacities of Li0.96Nb0.008FePO4/C cathode material were 161, 148, and 132 mAh•g−1 at the charge and discharge rates of 0.5C, 1C, and 2C, respectively. The results of cyclic voltammetry and EIS analyses showed that the resistance and polarization of the LiFePO4/C composite electrode could be effectively decreased by Nb doping, which would improve the electron conductivity of LiFePO4.

Key words: Lithium ion battery, Cathode material, Nb doping, LiFePO4/C, Electrochemical performance