β-Ni(OH)_2/C混合超级电容的电极行为

Electrode Performance of β-Ni(OH)_2/C Hybrid Capacitor

分别利用 β -Ni(OH) 2 和活性炭作为正、负极活性物质 ,通过循环伏安和双电极恒流充放电测试考察了镍正极与碳负极组合成混合超级电容电极在KOH电解液中的电极行为 .结果表明 ,镍正极的法拉第电化学反应过程和碳负极非法拉第双电层过程可以很好的结合起来 ,体现出超级电容的充放特性 .对于碳电极对 ,由于正极容量的限制 ,使得工作电压仅为 1V左右 ,双电极比容量为 39.6F/ g ,而镍正极 /碳负极组合工作电压可高达 1.5V ,双电极比容量能达到 90 .7F/ g .在相同电流下进行充放电 ,镍 /碳电极对功率密度可达到碳电极对的 2～ 3倍 ,能量密度可高达 10倍 .

The electrode perfomance of nickel positve/carbon negative hybrid capacitor electrode pair with β-Ni(OH) 2 and activated carbon as positive and negative electrode material in KOH electrolyte was measured through cyclic voltammetric and double_electrode galvanostatic change/discharge measurmements.The results proved that ,the combination of faradic electrochemical reaction process on nickel electrode and non_faradic double layer capacitance process on carbon electrode enables the nickel positivel/carbon negative electrode pair to have a very good supercapacitor performance.The working voltage and double electrode specific capacitance of a carbon/carbon electrode pair could only be 1?V and 39.6 F/g respectively because of the specific capacitance limitation of positive electrode,and the working voltage and double electrode specific capacitance of a nickel/carbon electrode pair could be up to 1.5 V and 90.7 F/g respectively .Charged/discharged at the same curent value,the power density of a nickel/carbon electrode pair could be 2～3 times larger than that of a carbon/carbon electrode pair,and the energy/density could be even ten times larger.