TECHNOLOGY FOCUS - ELECTRONICS - Preferred Arrangement: The anode and cathode are arranged opposing each other. A separator containing insulating porous material is arranged between the anode and cathode. A portion of anode, cathode and/or separator contains the non-aqueous electrolyte solution.    TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Materials: Carbon material (I) and carbon material (II) are fibrous activated carbon with aspect ratio of 1.5 or more.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Monomer: The monomer of formula (1) is thiophene, 3-methyl thiophene, 3-butyl thiophene, 3-phenyl thiophene and/or 3-methoxy thiophene.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Materials: Carbon material (I) and carbon material (II) are fibrous activated carbon with aspect ratio of 1.5 or more.    TECHNOLOGY FOCUS - POLYMERS - Preferred Polymers: The conductive polymer (I) has the molecular structure containing repeating unit based on monomer of formula (II), preferably repeating unit based on indole, ethylene dioxythiophene and/or 3-(4-fluorophenyl)thiophene.R3=H or alkyl group;andR4 and R5=same as R1 and R2.Preferred Method: The conductive polymer (II) is formed by electrolytic polymerization on carbon material (II). The electrolytic polymerization is carried out by immersing, carbon material-containing electrode which has the cathode active material content layer containing carbon material (II) formed on collector having electronic conductivity as a working electrode in a solution which contains the monomer of formula (I) and/or carbon material (II). EXAMPLE - A coating liquid containing FR25 (fiber activated carbon) (in mass parts) (80) and fluororubber binder (10) dissolved in methyl isobutyl ketone was applied on aluminum foil and dried to from active carbon-containing working electrode. The electrode was vacuum-dried, immersed in monomer solution containing thiophene, lithium hexa fluoro boride and propylene carbonate and subjected to electrolytic oxidation polymerization, to obtain electrode (A). Similarly electrode (B) containing fibrous activated carbon covered with pyrrole and ethylene dioxythiophene was formed. A cellulose film of 50 microns thickness impregnated with propylene carbonated solution was arranged between electrodes (A and B) and accommodated in a case, form electrochemical capacitor. The difference in redox potential of electrodes (A and B) was 0.44 V. The capacitor had high capacitance.