An asymmetric capacitor (ASC) employs electrodes of differing capacitances, separated by an electrolyte. In this setup, the larger electrode, made of a material with superior specific capacitance, has a higher absolute capacitance than the smaller one.
Asymmetric capacitors over hybrid capacitors Based on the electrode materials the supercapacitors are of two types- symmetric supercapacitors and asymmetric supercapacitors.
In asymmetric supercapacitor, MnS//EDAC shows a superior device performance with specific capacitance of 110.4 F g −1 and 89.87% specific capacitance retained after 5000 cycles. Importantly, the device exhibits a high energy density of 37.6 Wh kg −1 at a power density of 181.2 W kg −1 and remains 24.9 Wh kg −1 at 5976 W kg −1.
Asymmetric capacitors can be applied for new type of advanced propuslion. This technology require electric input power but fuel is not necessary. It is not reactive ion flow. Published in 2004, New Energy Technologies, issue #16. ISSN 1684-7288
The most notable asymmetric supercapacitor electrodes being used are AC and MnO 2 along with AC-Ni (OH) 2 . AC/MnO 2 is one of the most promising materials that have been widely reported for energy storage . Asymmetric supercapacitors can achieve high energy and power density .
Flexible asymmetric supercapacitors (ASCs) based on hybrid thin-film electrodes of transition-metal-oxide nanowire and single-walled carbon nanotube (SWNT) were successfully constructed by Po Chiang Chen et al.