Energy storage device for the current collector

A current collector for use in an electric double-layer capacitor is constructed such that it is held in intimate contact with the electrodes thereby reducing the internal resistance and providing for better charging and discharging characteristics. The current collector includes an electrically conductive metal foil having a plurality of through holes defined therein and a plurality of pointed bars projecting from edges of each of the through holes perpendicularly to the electrically conductive metal foil. The pointed bars extend through electrodes disposed on opposite surfaces of the current collector. Distal end portions of the pointed bars are bent over against the outer surfaces of the electrodes. The bent distal end portions hold the electrodes under pressure against the current collector so that the current collector and the electrodes are tightly fastened together. Preferably, the electrically conductive foil includes aluminum foil and each of the electrodes contains activated carbon.