摘要
LiFePO4电极的倍率特性与材料的粒度和电子导电性有很大关系.采用共沉淀方法,调控预处理温度,将3种不同尺寸的FePO4前驱体通过表面修饰对-羟基苯甲酸的聚合物,可合成不同尺度的LiFePO4/C材料,分别为80 nm、200nm和1μm.纳米尺度LiFePO4-a/C电极,30C放电比容量达到了100 mAh·g-1,而微米级LiFePO4-c/C电极放电比容量仅为54mAh·g-1.均一碳包覆的LiFePO4/C电极表现出强抗氧化性,不仅提高其导电性,还可防止材料氧化.
We adopted an effective route to prepare the particle size controllable core-shell structure carbon-coated LiFePO 4 from different sized FePO4 precursors, varying from 80 nm, 200 nm and 1 μm by an in situ polymerization method integrated with a surface modification technology. The discharge capacities of the three sized LiFePO4 /C are, respectively, 162 mAh·g^-1, 142 mAh·g^-1 and 92 mAh·g^-1at 0.1C rate. The nano-sized LiFePO4-a/C（80 nm） delivers a discharge capacity at large as 100 mAh·g^-1at even at 30C, while the macroscopic LiFePO4-c/C（1 μm） exhibits a much poorer discharge capacity of 54 mAh·g^-1under the same current density. The carbon coated LiFePO4（LiFePO4 /C） also shows good chemical stability after the exposure to air atmosphere, in which the uniform carbon layer could prevent the LiFePO4 from reacting with H2 O and O2.
出处
《电化学》
CAS
CSCD
北大核心
2013年第6期550-557,共8页
Journal of Electrochemistry
基金
国家自然科学基金重点项目(No.20925312)资助
作者简介
通讯作者，Tel：（86—21）51630318，E-mail：yyxia@fudan．edu．cn
