摘要
制备了不同比例的活性炭复合LiMn_2O_4电极材料,研究其在1mol/L Li_2SO_4溶液中的电化学性能。循环伏安结果表明复合后电极材料的电容包含活性炭的双电层电容和LiMn_2O_4电化学反应的法拉第电容,复合后响应电流在0～0．6V范围内有所增加,且含80%活性炭时响应电流达到最大;恒流充放电结果表明含80%活性炭时的放电曲线也基本呈直线,表现出较好的电容特性,仅复合了20%的LiMn_2O_4,其容量却增加了25%;交流阻抗结果表明含80%活性发的复合电极的溶液欧姆电阻仅为0．1Ω,呈现出更理想的电容行为。
LiMn2O4 /activated carbon composite materials with different proportion were synthesized. And the electrochemical performances of composite electrode materials were investigated in lmol/L Li2SO4 solution by means of different electrochemical techniques. The cyclic voltammetric curves show that the capacitances of composite electrode materials include double-layer capacitance of activated carbon and the Faraday capacitance of the electrochemical reaction of LiMn204. After the composite electrode is synthesized, the response current increases in the potential range of 0 to 0.6V. In addition, the response current reaches to peak value with 80% activated carbon content. From the charge-discharge curves, it is obvious that the discharge curve of the composite electrode with 80 % activated carbon content is linearity relation, and the composite electrode represents good capacitance performance as well the capacitance increases 25% with compounding only 20% LiMn2O4. The results of AC impedance testing indicate that the solution resistance of composite electrode with 80% activated carbon content is only 0.1Ω, which represents ideal capacitance performance.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2007年第4期586-588,591,共4页
Journal of Functional Materials
基金
教育部博士点基金(20050217019)
关键词
LIMN2O4
活性炭
超级电容器
复合材料
LiMn2O4
activated carbon
supercapacitor
composite electrode materials
