提高正极材料磷酸铁锂倍率性能的研究进展

Research progress in rate performance of LiFePO_4 cathode materials

橄榄石结构的磷酸铁锂(LiFePO4)被认为是潜力巨大的锂离子动力电池的正极材料,具有理论比容量高、安全性好、循环寿命长、环境友好和原料来源广泛等优点。但是,由于其本身结构的缺陷,导致其倍率性能低下。本文阐述了近年来改善LiFePO4的倍率性能的研究,重点介绍了包覆碳导电层、掺杂金属离子、合成纳米材料、制备多孔材料等方法,其中以纳米颗粒为基本结构单元的多孔LiFePO4微米球材料倍率性能优异、体积能量密度高,具备广阔的研究和应用前景。

Olive structure lithium iron phosphate LiFePO4 is considered as a promising cathode material for lithium ion power battery due to its high theoretical capacity,high safety,long cycle life,environmental benign and abundant raw material source.However,the instinct drawbacks of olive structure induces a poor rate performance.In this paper,methods for enhancing its rate performance are reviewed,including carbon coating,cation doping,synthesis nanoscale materials and preparing porous materials,etc.Among all the methods,LiFePO4 microsphere material,assembled by nanoparticles basic structure,displayed high rate performance and high volume energy density,has vast prospection.