We have fabricated two types of supercapacitors, redox and hybrid, based on poly(ethylenedioxythiophene) (PEDOT) and MSP-20 powder as electrode materials with Et4NBF4 in PC and LiPF6 in EC/DMC as electrolyte solutions. The redox type of supercapacitor is assembled with two PEDOT electrode sheets, while the hybrid type with PEDOT and MSP-20 electrode sheets. Their electrochemical properties in different electrolyte solutions and cut-off voltage range are investigated. From the results of charge and discharge for the hybrid type, the specific discharge capacitance of 56 F/g after 1000th cycle in the range 0-3 V is observed with LiPF6 in EC/DMC system. The electrochemical properties of the hybrid type supercapacitor are shown much better than them of the redox type. (C) 2004 Elsevier Ltd. All rights reserved.