物理化学学报 >> 2008, Vol. 24 >> Issue (08): 1498-1502.doi: 10.3866/PKU.WHXB20080829

研究简报 上一篇    下一篇

掺杂Mo的LiFePO4正极材料的电化学性能

陈宇; 王忠丽; 于春洋; 夏定国; 吴自玉   

  1. 北京工业大学环境与能源工程学院, 北京 100022; 北京联合大学生物化学工程学院, 北京 100023; 中国科学院高能物理研究所, 北京同步辐射实验室, 北京 100049
  • 收稿日期:2008-02-04 修回日期:2008-03-21 发布日期:2008-08-06
  • 通讯作者: 夏定国; 吴自玉 E-mail:dgxia@bjut.edu.cn;wuzy@ihep.ac.cn

Electrochemical Properties of Mo-Doped LiFePO4 Cathode Material

CHEN Yu; WANG Zhong-Li; YU Chun-Yang; XIA Ding-Guo; WU Zi-Yu   

  1. College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100022, P. R. China; Biochemical Engineering College of Beijing Union University, Beijing 100023, P. R. China; Beijing Synchrotron Radiation Facility, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P. R. China
  • Received:2008-02-04 Revised:2008-03-21 Published:2008-08-06
  • Contact: XIA Ding-Guo; WU Zi-Yu E-mail:dgxia@bjut.edu.cn;wuzy@ihep.ac.cn

摘要: 通过固相法以(NH4)6Mo7O24·4H2O为钼源, 在氮气气氛下合成出掺杂Mo的LiFePO4正极材料. 采用X射线衍射(XRD)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、扩展X射线吸收精细结构(EXAFS)和正电子湮没进行结构表征, 通过不同放电倍率研究掺Mo的LiFePO4电化学性能. 结果表明, 掺Mo的LiFePO4呈橄榄石结构, Mo6+同时占据着Fe位及Li位, 提高了LiFePO4的电导率, 1C放电可逆容量为141 mAh·g-1, 表现出良好的电化学性能.

关键词: 磷酸亚铁锂, 固相法, 离子掺杂, 电子电导率

Abstract: Mo-doped LiFePO4 was prepared using (NH4)6Mo7O24·4H2O as doping starting material by solid state method under N2 atmosphere. The Mo-doped LiFePO4 samples were characterized by X-ray diffraction, scanning electron microscope, X-ray photoelectron spectrum, extended X-ray absorption fine structure, positron annihilation technique, and electrochemical performance testing at different discharge rates. The results showed that Mo-doped LiFePO4 preserved pure olivine structure. Mo6 + occupied Fe site and Li site simultaneously and the electronic conductivity of LiFePO4 increased. The Mo-doped LiFePO4 had a reversible capacity of 141 mAh·g-1 at 1C discharge rate, and showed good electrochemical properties.

Key words: LiFePO4, Solid-state reaction, Doping-ion, Electronic conductivity

MSC2000: 

  • O646