Abstract: To enhance the bondability or the sealability between an opening shield plate and a capacitor case and between a resin made opening shield member and an aluminum terminal, and to effectively suppress a leakage of electrolyte liquid from these interfaces, an opening shield plate including a resin made opening shield member bonded to an outer circumference of an aluminum terminal and an aluminum made opening shield member bonded to said resin made opening shield member, wherein said shield resin made opening shield member is made of PFA resin, and said aluminum made opening shield member is welded to a capacitor case.

Abstract: An electric double-layer capacitor housing has a bottomed outer case for accommodating an electric double-layer capacitor therein, a lid closing an open end of the bottomed outer case, the lid having a through hole defined therein, an electrode terminal mounted in the through hole in the lid for electrically connecting the electric double-layer capacitor in the bottomed outer case to an external circuit, and an insulative sealing member interposed between the lid and the electrode terminal and sealing the through hole. The electrode terminal includes a terminal body, a projecting rod extending from the terminal body, an outer sleeve spaced radially outwardly from the projecting rod, a tapered portion spreading radially outwardly and downwardly, and a flange extending radially outwardly from the tapered portion.

Abstract: An electric double-layer capacitor includes a plurality of electrode elements each having a current collector, a polarized electrode disposed on a surface thereof, and a strip-like current collecting lead extending from an end of the current collector. The electrode elements are stacked as alternately belonging to respective polarities, and the current collecting leads of the electrode elements are stacked into lead assemblies of the respective polarities. A separator is interposed between the stacked electrode elements, and the lead assemblies are connected respectively to electrode terminals. The lead assemblies of respective polarities serve as respective connectors connected to the electrode terminals. Each of the connectors has a flat joint region as at least a portion thereof. The current collecting leads of each of the lead assemblies are integrally joined to each other by the flat joint region by ultrasonic welding before the connector is connected to the electrode terminal.

Abstract: 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.