文献类型：期刊文献

中文题名：PEG分子量对LiFePO_4/C纳米复合正极材料结构与电化学性能的影响

英文题名：Effect of Molecular Weight of PEG on the Structure and Electrochemical Properties of Nanosized LiFePO_4/C Composite Cathode Material

作者：马新胜[1,2];徐永刚[1];黄新虎[1];张洁[1];徐云龙[1,2];于建国[2]

机构：[1]华东理工大学材料科学与工程学院,上海200237;[2]华东理工大学国家超细粉末工程研究中心,上海200237

年份：2010

卷号：18

期号：4

起止页码：410

中文期刊名：合成化学

外文期刊名：Chinese Journal of Synthetic Chemistry

收录：CSTPCD;;北大核心:【北大核心2008】；CSCD:【CSCD_E2011_2012】；

基金：国际合作基金资助项目(08230705600);上海市纳米科技专项资助项目(0852nm02300)

语种：中文

中文关键词：磷酸锂铁;PEG;电导率;电化学性质

外文关键词：LiFePO4/C; PEG; electronic conductivity; electrochemical property

摘要：以聚乙二醇(PEG)为纳米结构控制剂和碳源,采用液相法合成了纳米复合正极材料LiFePO4/C,其结构与电化学性能经XRD,SEM和恒电流充放电测试等表征。考察了4种不同分子量的PEG对LiFePO4/C晶型结构、粒径、形貌及充放电性能的影响。结果表明:随着PEG分子量的增大,LiFePO4/C的粒径减小、电导率增大、电化学性能提高。以PEG 4000合成的LiFePO4/C(Fd)的粒径小于50 nm,电导率为8.58×10-4S.cm-1,0.1C倍率下首次放电比容量高达165.8 mAh.g-1,循环20次后容量无衰减;1C倍率下,首次放电比容量为108.1 mAh.g-1,表明Fd具有优良的倍率性能。
Nanosized LiFePO4/C composite cathode material was synthesized by liquid phase method using polyethylene glycol（PEG） as the template and the carbon source.The structure and electrochemical properties of LiFePO4/C were characterized by XRD,SEM and constant current charge-discharge experiments.The influences of PEG with different molecular weights on crystal structure,particle size,morphology and electrochemical properties of LiFePO4/C were investigated.The results showed that with the increase of molecular weight of PEG,the particle size reduced,the electronic conductivity and electrochemical performance of LiFePO4/C were improved.The Fd（using PEG 4000 as the carbon source） had a fine particle size below 50 nm and the electronic conductivity was 8.58×10^-4 S·cm^-1.A discharge capacity of 165.8 mAh·g^-1 under 0.1C was obtained with no capacity fading over 20 cycles and the discharge capacity was 108.1 mAh·g^-1 at the rate of 1C,which reveals excellent electrochemical performance of Fd.