摘要
用共沉淀的方法制备了改性的锂离子电池正极材料LiFePO4,利用X射线衍射(XRD)、扫描电镜(SEM)、傅立叶红外光谱(FTIR)等方法对样品的晶体结构、表观形貌、谱学性质等进行了分析研究,并在表观形貌和电性能上与固相法制备的样品进行比较。结果表明,此种方法制备的LiFePO4为单一的橄榄石型晶体结构,具有3.4V左右的放电电压平台,该材料具有良好的电性能,分别以0.2,0.4mA/cm2的电流密度充放电,首次放电比容量达到142.3,127mAh/g,充放电循环20次后放电比容量仍保持在129.7,105.5mAh/g。
The cathode materials of LiFePO4 were synthesized under liquid-state co-precipitation method. The crystalline structures, morphology of particles, spectroscopic character were investigated by X-ray diffraction, scanning electron microscopy and FTIR. Morphology of particles and electrochemical performance were also compared with that synthesized by solid-state reaction. The results showed that LiFePO4 were simple pure olive-type phase, and exhibit a 3.4 V discharge voltage plateau. LiFePO4 as prepared possessed excellent electrochemical performance, whose first specific capacities were 142.3 mAh/g at 0.2 mA/cm2, 127 mAh/g at 0.4 mA/cm2, after 20 times cycling, the specific capacities were 129.7 mAh/g, 105.5 mAh/g respectively.
出处
《材料工程》
EI
CAS
CSCD
北大核心
2005年第6期36-40,共5页
Journal of Materials Engineering
关键词
锂离子电池
正极材料
LIFEPO4
共沉淀法
Li-ion battery
cathode material
LiFePO_4
liquid-state co-precipitation method
