An electrochemical supercapacitor with a polymeric active electrolyte was designed and fabricated in thiswork. A water-soluble conducting polymer, sulfonated polyaniline (SPAni), was used in the supercapacitoras the active electrolyte and a semipermeable membrane was employed as the separator of the device. Itwas found that SPAni in the electrolyte can provide pseudocapacitance via its reversible electrochemical
redox reaction. Owing to the good stability of SPAni, the supercapacitor has a long cycling life.Moreover, the migration of SPAni between the two electrodes was blocked by the semipermeablemembrane separator, thus self-discharge caused by the shuttle effect of SPAni was suppressed. The research in this paper demonstrates the possibility of using a polymer as the active electrolyte in asupercapacitor and has paved a new way to achieve active electrolyte enhanced supercapacitors withhigh capacitance and good energy retention.
