摘要
橄榄石型的LiFePO4材料是一种具有良好发展潜力的锂离子电池阴极材料。应用一种两步烧结的碳热还原方法制备出LiFePO4阴极材料,该法缩短了高温烧结阶段的时间,从而达到抑制晶粒长大的目的,并对LiFePO4进行原位碳包覆,制得LiFePO4/C复合阴极材料。对制得的材料进行0.1C恒电流充放电测试,首次放电容量为149.4mAh/g,首次放电效率可以达到93.5%。而用作对比的一步法烧结碳热还原样品在0.1C恒流充放电试验中首次容量只有99.1mAh/g,放电效率是81.4%,并对制备反应及充放电结果的机理进行了探讨。
Olivine-structured LiFePO4 is a promising cathode material for lithium-ion batteries.A two-step carbothermal reduction method was used in synthesizing LiFePO4 cathode materials in this study.Decreasing high-temperature sintering time of the two-step method restrained the growth of the particle.At the same time,carbon was wrapped on the surface of LiFePO4 particle.And a LiFePO4/C composite cathode material was formed.The results showed that the initial discharge capacity of this sample was 149.4mAh/g at 0.1C rate and the discharge efficiency reached 93.5%.On contrary,the one-step carbothermal reduction sample had an initial discharge capacity for 99.1mAh/g.And the discharge efficiency is 81.4%.Then the mechanism of synthesis reaction and electrochemical result was analyzed.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2011年第11期2030-2033,共4页
Journal of Functional Materials
基金
教育部创新团队发展计划资助项目(IRT0739)
上海市科委资助项目(09dz1203602)
关键词
磷酸铁锂
碳热还原
复合阴极材料
碳包覆
两步烧结
LiFePO4
carbothermal reduction
composite cathode materials
carbon coated
two-step method
