Abstract:Electrochromic functionality is introduced into supercapacitors to preventing them from overcharging. A high-performance electrochromic supercapacitor electrode material based on barium titanate (BT) and polythiophene (PEDOT) was successfully prepared by chemical oxidation polymerization. The electrode material shows core-shell nanostructures and a high capacitance value of 115.3 F/g, and can retain 93.0% of the initial capacitance value after 1 500 cycles. In addition, due to the electrochromic characteristics of PEDOT, the prepared composite electrode will undergo color changes during the charging and discharging process and has an optical modulation of 52.9% before and after being fully charged and discharged, thus enabling electrochromic energy storage. This electrochromic supercapacitor electrode directly displays the current energy storage level in an observable way.