Supercapacitor based on activated carbon and polyethylene oxide-KOH-H2O polymer electrolyte

For the first time, a totally solid state electric double layer capacitor h as been fabricated using an alkaline polymer electrolyte and an activated c arbon powder as electrode material. The polymer electrolyte serves both as separator as well as electrode binder. The capacitor has a three-layer stru cture: electrode-electrolyte-electrode with a final thickness of ca. 1.5-2 mm, diameter of 1.8 cm (surface of 2.5 cm(2)) and a mass of ca. 300-500 mg. Cyclic voltammetry, galvanostatic cycling and impedance spectroscopy have been used for the determination of the electrochemical performance of proto type capacitors and a capacity of ca. 1.7-3.0 F for a 1 V voltage range has been measured. (C) 2001 Elsevier Science Ltd. All rights reserved.