Electrochemical redox supercapacitor. The supercapacitor includes two thin films of electrically conducting polymer separated by an ion-permeable membrane and including an electrolyte disposed between the two thin films. Electrical contacts are disposed on outer surfaces of the two thin films. The supercapacitor is flexible and may be rolled, folded on itself, or kept substantially flat. A suitable conducting polymer is polypyrrole. In another aspect, the invention is a method for making a redox supercapacitor.