摘要
通过综述碳质材料对磷酸铁锂(LiFePO4)电极材料物理和电化学性能的影响,评述了碳质材料在不同LiFePO4/C复合电极材料中的作用及其优缺点。指出:炭膜的原位包覆和模板炭的引入,限制了LiFePO4晶粒的生长,进而提高了电极材料的电导率;而导电炭和石墨烯的引入,则是直接提高了电极材料的电导率;有机结合这两种碳质材料的复合方式将会极大改善电极材料的电化学性能。但是,为了提高电极材料的体积能量密度及其振实密度,应该最大限度地降低碳质材料在LiFePO4/C复合电极材料中的含量。
The effects of carbonaceous materials on the physical and electrochemical performance of LiFePO4/C hybrids are reviewed.The major role,advantages and disadvantages of carbon-based materials in LiFePO4/carbon hybrids are discussed.The introduction of an in situ grown carbon coating would be beneficial to limiting the LiFePO4 particle growth and increasing the electric conductivity.The structure and precursors of the in situ grown carbons have a great influence in the rate performance of the hybrids,which can be related to an improved electron and ion transfer rate.Deposition of LiFePO4 into a carbonaceous matrix such as a templated membrane can increase the contact area between the active materials and the electrolyte,which favors a fast ion transport.The addition of conductive carbon and graphene would only effectively increase the electrical conductivity.In order to achieve an excellent electrochemical performance of LiFePO4,it is necessary to take advantage of and to combine these approaches to optimize electron and ion transfer rates.Also,it is most important to minimize the carbon content in LiFePO4/carbon hybrids to increase volumetric energy density and tap density when practical applications in electric vehicles are targeted.
出处
《新型炭材料》
SCIE
EI
CAS
CSCD
北大核心
2011年第3期161-170,共10页
New Carbon Materials
基金
National Nature Science Foundation of China under Grant(50632040,50802049)
Guangdong Province Innovation R&D Team Plan and Shenzhen Technical Plan Project(JP200806230010A,SG200810150054A)~~
关键词
磷酸铁锂
炭包覆
炭基体
导电炭
碳纳米管
石墨烯
Lithium iron phosphate
Carbon coating
Carbonaceous matrix
Conductive carbon
Carbon nanotube
Graphene
