A novel hybrid supercapacitor based on spherical activated carbon and spherical MnO2 in a non-aqueous electrolyte

A novel non-aqueous hybrid supercapacitor was fabricated from two spherical materials – an activated mesocarbon microbead (AMCMB) and MnO2 nanowire-sphere, as the negative and positive electrodes, respectively. The preliminary results for this energy-storage device, which operates over a wide voltage range (0.0–3.0 V) using 1 M Et4NBF4 in acetonitrile (AN) as electrolytes, are presented. On the basis of a single electrode, the AMCMB|MnO2 supercapacitor displays a high specific capacitance of 228 F g−1 at a scan rate of 10 mV s−1, corresponding to specific energy of 128 W h kg−1 based on based on the total mass of active materials, while maintaining desirable cycling stability and rate capability. The combination of the spherical AMCMB and MnO2 in a non-aqueous electrolyte is proved to be suitable for high-performance hybrid supercapacitor applications.