动力型锂离子电池正极材料LiFePO_4的改性研究  

Modification Techniques in LiFePO_4 as Cathode Material in

作　　者：赵建庆[1] 何建平[1] 赵伟[1] 殷健程[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院,南京210016

出　　处：《化学通报》2011年第3期238-243,共6页Chemistry

摘　　要：橄榄石型LiFePO4具有高的理论比容量、高倍率特性、优越的电化学和热稳定性能、循环寿命长且绿色环保等优点,被认为是新一代动力型锂离子电池理想的正极材料之一。LiFePO4因本身结构的缺陷导致了其极低的电导率和Li+扩散速率,限制了该材料在动力电池的中实际应用。本文综述了通过表面包覆修饰、金属阳离子晶体结构内掺杂和导电介质引入等技术来提高LiFePO4的电导率和Li+扩散速率的改性,以实现LiFePO4在高倍率条件下的快速充放电的进展,着重介绍了具有三维多孔碳骨架结构支撑的LiFePO4/C复合材料的研究现状及其应用前景。Olivine LiFePO4 has been considered as a promising cathode material for high power lithium ion batteries due to various advantages in terms of high theoretical capacity,high-rate capability,outstanding long-term cycle performance,safety and environmental benignancy.The extremely low electronic conductivity and lithium ion diffusion coefficient of LiFePO4 are attributed to the inherent structural drawbacks,which considerably limit the power density of LiFePO4 in practical applications.Here,main modification techniques,including surface coating modification,metallic cation doping in crystal cell,mixture of conductive medium and synthesis of LiFePO4/C composites supported with a three-dimensional porous carbon framework as cathode material,and so forth,for improving electrochemical performance and properties of LiFePO4 were reviewed.The LiFePO4/C composites are attractive with novel structure in combination with excellent electrochemical performance in high-rate capability,and are expected to extensively apply in high power lithium ion batteries.

关 键 词：动力型锂离子电池 正极材料 LiFePO4改性 

分 类 号：TM912[电气工程—电力电子与电力传动]