复合材料LiMn_2O_4/活性炭的电化学行为  

Electrochemical performance of LiMn_2O_4/activated carbon composite material

作　　者：马婷婷[1] 王志兴[1] 李新海[1] 郭华军[1] 方杰[1] 彭文杰[1] 胡启阳[1] 张云河[1] 

机构地区：[1]中南大学冶金科学与工程学院,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2012年第1期17-22,共6页Journal of Central South University:Science and Technology

基　　金：国家重大科技支撑计划项目(2007BAE12B00)

摘　　要：利用充放电测试、循环伏安和交流阻抗等方法研究LiMn2O4/活性炭复合材料在1 mol/L LiPF6-EC/EMC/DMC有机电解液中的电化学性能。研究结果表明:复合材料同时具备超级电容器高功率密度和锂离子电池高能量密度的特点;复合材料的容量包含活性炭的双电层电容和LiMn2O4电化学反应的容量;当活性炭的质量分数为20%时,10C倍率下复合材料的首次放电容量高达76.4 mA.h/g,100次循环后容量几乎没有衰减(0.01%),与纯LiMn2O4电极相比有很大提高。The electrochemical performances of the composite material based on activated carbon and LiMn2O4 were characterized by rate charge-discharge,cyclic voltammograms and electrochemical impedance spectra.It is demonstrated that the composite material has advantages of both the high power density of the supercapacitor and the high energy density of the lithium ion battery.Moreover,the electrochemical measurements also show that the composite material has good cycle life performance.At 10C rate,the discharge capacity of the composite material（80% LiMn2O4＋20% activated carbon,mass fraction） is 76.4 mA-h/g,which is greatly improved compared with that of LiMn2O4.The capacity loss in constant current-constant voltage mode is no more than 0.01% after 100 cycles.

关 键 词：超级电容器 LIMN2O4 复合材料 锂离子电池 

分 类 号：TM912.9[电气工程—电力电子与电力传动]