摘要
采用固相法合成磷酸铁锂锂离子电池正极材料。X射线衍射分析(XRD)显示合成的样品具有橄榄石晶型结构。扫描电镜(SEM)结果显示LiFePO4的大小在0.5～2.5μm,并且形状不规则。通过电化学测试研究了不同物料配比和涂膜厚度对LiFePO4电化学性能的影响。结果显示:当物料配比为85:10:5、涂膜厚度为200μm时,以LiFePO4为正极的电池在0.1C下首次放电比容量为134.8mAh/g。从循环伏安测试(CV)发现,优化后的样品对于Li+的脱出与嵌入具有很好的可逆性,这一性能同样被交流阻抗分析(AC)所证实。
Lithium iron phosphate (LiFePO4) powders were synthesized by a solid state method. X-ray diffraction (XRD) patterns reveal an orthorhombic olivine-type structure. The scanning electron microscopy (SEM) result indicates that LiFePO4 particles possess the size 0.5-2.5 μm and an irregular shape. Electrochemical test indicates the performance of LiFePO4 cathode material with different mixture ratio in different spread thickness. The cathode material with the mixture ratio of 85:10:5 in 200 μm has the discharge capacity of 134.8 mAh/g at the current of 0.1 C. From the result of cyclic voltammetry, it is found that the optimized sample has good reversibility for lithium extraction/ insertion reactions, which is further proven by impedance analysis.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2010年第S2期77-80,共4页
Rare Metal Materials and Engineering
基金
National Natural Science Foundation of China (50874074, 50474092)
Guangdong Natural Science Foundation (8151806001000028)
The Shenzhen Key Laboratory of Functional Polymer Foundation (FP20080003)
关键词
磷酸铁锂
锂离子电池
固相法
电化学性能
优化
LiFePO4
lithium ion battery
solid state method
electrochemical properties
optimization
