Influence of amorphous carbon nano-clusters on the capacity of carbon black electrodes

Electric double layer supercapacitor electrodes were prepared from a mixture of carbon black, amorphous carbon nano-particles and binder to obtain higher capacitance. The capacitance of the electrodes was calculated from the charge-discharge characteristics. Aluminium foil served as the current collector. The active material was laid on it by the spraying technique. The best adherence of the compound to the foil was achieved by the solution of hexamethylenediamine (HMDA), glycidyl methacrylate (GMA) and polytetrafluoroethylene (PTFE) in isopropanol. However, this binding mixture caused a loss in the capacitance because after the polymerization, it obstructs the pores of the carbon black, thus decreasing the active surface of the capacitor. To compensate this, plasma-prepared carbon nano-clusters were introduced into the capacitor electrode matrix, because this material has a large polarizability. The effect of the amorphous carbon nano-particle content of the prepared electrodes on the capacitance was studied. The maximal capacitance was obtained when the active material contained 30 wt.% of carbon nano-particles.