Abstract: An aluminum electrolytic capacitor with an aluminum housing defining a chamber, and having a feed-through aperture providing communication with the chamber from outside of the housing. A number of aluminum anode layers are positioned within the chamber, and a feed-through member formed of a first conductive material occupies the feed-through aperture. The feed-through member has an inner end extending into the chamber, an outer end extending externally from the housing, and an insulative sleeve encompassing an intermediate portion of the feed-through member and directly contacting the housing at the feed-through aperture to prevent electrical contact between the feed-through member and the housing. A connection element formed of a second different conductive material is attached to the inner end of feed-through member and spaced apart from the housing. A compressible insulative gasket may be positioned between the housing and the connection element to provide insulation and a fluid seal.

Abstract: A method for making anode foil plates for use with layered electrolytic capacitors and capacitors made with such plates. A high purity aluminum foil is provided for generation of anode foil plates. Sheets of the foil are highly etched to provide a very high surface area. Following the etch process, the foil is partially cut or punched into plates from the etched sheets in the general shape of the finished capacitor housing with a portion remaining connected to the supporting foil. The supporting foil with the partially punched-out etched plates are subjected to a forming process by applying a voltage to the plates in the presence of an electrolyte to provide formed anode foil plates with edges which do not have to be reformed during capacitor aging and which do not have any particulates at cut edges. The formed anode plates are layered with cathode plates and separators in a capacitor housing with an electrolyte to provide a finished capacitor.

Abstract: A capacitor and a method for making the capacitor using ultrasonic welding to join the cathode layers together are provided. The capacitor includes a housing defining a chamber with a step provided at an inner portion of the housing. A plurality of capacitor layers each including a cathode foil, a separator and an anode foil, each having alignment holes therein to precisely fit with alignment elements housing, is positioned within the chamber, with the alignment holes mating with the alignment elements. The housing is electrically conductive for connection to the cathode foils. Each cathode foil includes a cathode tab which extends away from the foil. The cathode tabs are pressed together and ultrasonically welded to the housing step abutting the periphery of the interior of the housing.

Abstract: A capacitor for an implantable cardiac defibrillator with a housing defining a chamber. A plurality of flat, stacked, charge storing layers reside within the chamber. Each of the layers includes at least a first and a second electrically conductive sheets separated by a sheet in between. The first sheet is electrically connected to the housing, and the second sheet is electrically isolated from the housing. The layers each have a periphery having at least one alignment element, with the second sheet extending to the periphery along at least a portion of the alignment element, such that the layers may be engaged at the alignment element to register the layers during assembly.

Abstract: A capacitor and a method for making the capacitor using ultrasonic welding to join the cathode layers together are provided. The capacitor includes a housing defining a chamber with a step provided at an inner portion of the housing. A plurality of capacitor layers each including a cathode foil, a separator and an anode foil, each having alignment holes therein to precisely fit with alignment elements housing, is positioned within the chamber, with the alignment holes mating with the alignment elements. The housing is electrically conductive for connection to the cathode foils. Each cathode foil includes a cathode tab which extends away from the foil. The cathode tabs are pressed together and ultrasonically welded to the housing step abutting the periphery of the interior of the housing.

Abstract: An improved electrolytic capacitor is provided by producing an anode foil which has areas which are not subject to stress during manufacturing being highly etched and those areas which are subject to stress during manufacturing being lightly etched or not etched at all. The process of the invention provides an etch mask to cover during the etch process those portions of the anode foil which will be subjected to stress during construction of the capacitor. The highly etched areas, which are very brittle, provide increased capacitance and thus improved energy density. For layered or stacked capacitors, a weld tab is covered with the etch mask to allow connection of the anode layers. Additionally, strong edges may be maintained thereby reducing the possibility of cracking that would normally occur during the stamping and assembly operations.

Abstract: An implantable cardiac defibrillator is provided having an energy source, a capacitor, and means coupled to the energy source for charging the capacitor. The capacitor comprises a planar layered structure of anode plates, cathode plates and means separating the anode plates and cathode plates. A polymeric envelope containing electrolyte encloses the layered structure. Electrical contact means extend from the anodes and cathodes to outside the envelope.

Abstract: An electrolytic capacitor capable of withstanding high vibration environments includes a cylindrical capacitor case having an open end and a closed end, and cylindrically rolled alternate wraps of electrolyte impregnated paper and metal foil films with tabs abutting the foil films to electrically connect each of the foil films to a terminal. With the paper film on the outside of the cylindrical roll, the roll's outside diameter is tightly controlled to provide a snug fit when inserted in the case while the inside diameter of the roll is sized to provide a cylindrical volume in cubic inches equal to approximately 1.2 times the actual capacitance in farads times the desired rated voltage in volts so as to prevent a large pressure rise due to gas generation during capacitor operation. The paper films are axially longer than the other films towards the open end of the case while one of the foil films is axially longer towards the closed end of the case than the other films.

Abstract: A capacitor which includes a case containing a capacitor element with multiple tabs extending therefrom is provided with a header which carries a pair of terminal members. Each of the terminal members has a pair of parallel connector leads extending out of the header connected by terminal portions inside the case. Each of the terminal portions includes portions parallel and nonparallel to corresponding terminal portions of the other terminal member and each of the tabs is welded to the outside of a parallel terminal portion.

Abstract: A capacitor which includes a case containing a capacitor element with a pair of unequal length overlapping tabs extending therefrom. A header for sealing the case carries a pair of leads. Each tab is welded to one of the leads with an insulator interposed between the tabs.