Electrochemical supercapacitors based on carbon aerogels/Ni(OH)(2) composites and activated carbon

Purpose - The purpose of this paper is to show how to obtain a supercapacitor with high specific power (P) and high specific energy (E-p) simultaneously. Design/methodology/approach - The carbon aerogels are obtained by ambient pressure drying method instead of supercritical drying method and carbon aerogels/Ni(OH)(2) composites are prepared by in situ polymerisation. A series of asymmetric supercapacitors based on carbon aerogels/Ni(OH)(2) composites as positive electrode and activated carbon as negative electrode, respectively, are assembled. The electrochemical performances of carbon aerogels/Ni(OH)(2) composites and supercapacitors are studied. Findings - The results show that the specific capacitance (C-p) of carbon aerogels/Ni(OH)2 composites is 584 F/m(2). The working potential of supercapacitors could be increased to 1.6V. When the mass ratio of carbon aerogels and Ni(OH)2 is 3:7, the mass ratio of positive electrode and negative electrode is 1:1, the E-P and P of the supercapacitor is higher than 10.5 Wh/kg and 578 W/kg, respectively, when the current varies from 50 mA to 100 mA and the attenuation ratio of C-p is only 8.3 per cent after 10,000 cycles at 100 mA. Practical implications - The supercapacitors can be used in the field of automobile engineering and can solve the problems of energy shortage and environmental pollutions. Originality/value - The supercapacitor based on carbon aerogels/Ni(OH)(2) composites as positive electrode and activated carbon as negative electrode is novel and the synthetic properties of the supercapacitor are excellent.