摘要
以FePO4·xH2O为铁源与Li2CO3混合，以草酸为还原剂，在常温机械活化作用下合成出无定形态LiFePO4，然后低温热处理合成晶态的LiFePO4。考察了不同合成温度、时间对产物晶形结构、形貌和电化学性能的影响。结果表明，600℃热处理12h后制得的LiFePO4粒径细小且分布均匀，一次粒子粒径在100-200nm之间；该材料在0．1、0．2、0．5和1C下首次放电比容量分别为165、160、156和154mAh／g，50次循环后放电比容量分别为163、159．2、154．66和153．4mAh／g，容量保持率分别为98．8％、99．5％、99．1％和99．6％。
LiFePO4 was synthesized by heating an amorphous LiFePO4. The amorphous LiFePO~ obtained through lithiation of FePO4·xH2O by using oxalic acid as a novel reducing agent at room temperature. The effects of reaction temperature and time on the crystal structure, morphology and electrochemical properties of products were investigated. The results show that the sample synthesized at 600℃ for 12h has fine particle sizes between 100- 200nm, and with homogenous sizes distribution. The synthesized LiFePO4 composites shows high electrochemical capacity of 165,160,156 and 154mAh/g at the 0.1, 0.2, 0.5 and 1C rate. The cell retains 98. 8 %, 99.5 %, 99.1% and 99.6%of its initial discharge capacity after 50 cycles.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2008年第11期1843-1846,共4页
Journal of Functional Materials
基金
国家重点基础研究发展计划(973计划)资助项目(2007CB613607)
