NOVELTY - An electrode (101) has an electroconductive support (11) and an active material layer (12) provided on the electroconductive support and contains an electrode active material (13) and a conductive additive (14). The electrode active material contains polymer compound (A) having tetrachalcogeno fulvalene structure as a repeating unit of the main chain and/or polymer compound (B) which is copolymer including unit (a) containing tetrachalcogeno fulvalene structure in a side chain and unit (b) which does not contain the tetrachalcogeno fulvalene structure in a side chain.    USE - Electrode is used for electricity storage device (claimed). Uses include but are not limited to portable apparatus, transport apparatus, portable audio device, mobile telephone, sensor, electrochemical element, hybrid vehicle, motor-vehicle component and notebook personal computer.    ADVANTAGE - The electrode is lightweight, and has high energy density. The electricity storage device containing the electrode has high output, capacitance and repetition characteristics.    DETAILED DESCRIPTION - An electrode has an electroconductive support and an active material layer provided on the conductive supporting body and contains an electrode active material and a conductive additive. The electrode active material contains polymer compound (A) having tetrachalcogeno fulvalene structure as a repeating unit of the main chain and/or polymer compound (B) which is copolymer including unit (a) containing tetrachalcogeno fulvalene structure in a side chain and unit (b) which does not contain the tetrachalcogeno fulvalene structure in a side chain. In the active material layer, the electrode active material does not form particles and covers at least a portion of the surface of the conductive assistant. INDEPENDENT CLAIMS are included for the following:    (1) electricity storage device; and    (2) manufacture of electrode, which involves preparing mixture containing aprotic solvent and electroconductive support agent and removing aprotic solvent from mixture.    DESCRIPTION OF DRAWING(S) - The drawing shows sectional view of electrode.    Electroconductive support (11)    Active material layer (12)    Electrode active material (13)    Conductive assistant (14)    Electrode (101)