化学学报 ›› 2011, Vol. 69 ›› Issue (21): 2632-2636.DOI: 10.6023/A1103312B 上一篇    下一篇

研究简报

以二甲亚砜水溶液为反应介质低温合成纳米级磷酸亚铁锂

常照荣*,刘瑶,汤宏伟,赵海丽,黄静   

  1. (河南师范大学化学与环境科学学院 新乡 453007)
  • 投稿日期:2011-03-31 修回日期:2011-06-15 发布日期:2011-07-04
  • 通讯作者: 常照荣 E-mail:czr_56@163.com
  • 基金资助:

    低共熔混合锂盐合成高密度锂离子电池正极材料的研究

Low Temperature Synthesis of LiFePO4/C Nanocomposite in DMSO/H2O System

CHANG Zhao-Rong, LIU Yao, TANG Hong-Wei, ZHAO Hai-Li, HUANG Jing   

  1. (College of Chemistry and Environmental Science, Henan Normal University, Xinxiang 453007)
  • Received:2011-03-31 Revised:2011-06-15 Published:2011-07-04

采用二甲亚砜水溶液为反应介质, 在常压和108 ℃条件下, 经短时间的液相反应直接制备出橄榄石结构的纳米级LiFePO4. IR分析表明, 液相法直接制得的LiFePO4晶体结构中含有少量的Fe3+. 将液相直接制备的样品与少量葡萄糖混合后在600 ℃下焙烧3 h得到类球形的LiFePO4/C材料. 电化学测试结果表明, 这种纳米级LiFePO4/C材料在0.2 C 倍率下放电容量达到157.2 mAh/g, 并且具有较好的放电平台. 5 C和10 C放电容量仍能达到126.1和103.4 mAh/g, 且循环200次后容量没有明显衰减, 表现出优异的倍率放电特性和循环性能.

关键词: 液相法, 低温合成, 锂离子电池, LiFePO4/C, 二甲亚砜

Nanometer-sized LiFePO4 with a well-developed olivine-type structure was synthesized in the dimethyl sulfoxide (DMSO)/H2O system under ambient pressure and 108 ℃. From IR analysis, less amount of Fe3+ ions were proved to exist in the composite by solution-phased method. The sphere-like LiFePO4/C nanocomposite was obtained by sintering the mixture of nanometer-sized LiFePO4 and glucose at 600 ℃ under inert atmosphere for 3 h. The electrochemical tests showed the specific capacity of LiFePO4/C nanocomposites at discharge rates of 0.2 C was 157.2 mAh/g. A capacity of 126.1 mAh/g at 5 C and 103.4 mAh/g at 10 C was even achievable, with no significant capacity fading after 200 cycles.

Key words: solution-phased method, low temperature synthesis, lithium ion battery, LiFePO4/C, dimethyl sulfoxide (DMSO)