Abstract: A capacitor working electrolyte containing water and a silicate additive is described. The silicate additive does not alter the electrolyte properties and/or cause any separation of the electrolyte composition. Instead, it stabilizes capacitor long-term performance.

Abstract: A lithium electrochemical cell of either a primary or a secondary chemistry activated with an electrolyte having a cyclic carbonate of a ring size equal to or larger than a six-member ring is described. The cyclic carbonate helps to make the anode passivation film ionically conductive to thereby eliminate voltage delay during pulse discharge and to reduce Rdc. Such a cell is particularly well suited for powering an implantable medical device, such as a cardiac defibrillator.

Abstract: It is known that reforming implantable defibrillator capacitors at least partially restores and preserves their charging efficiency. An industry-recognized standard is to reform implantable capacitors by pulse discharging the connected electrochemical cell about once every three months throughout the useful life of the medical device. A Li/SVO cell typically powers such devices. The present invention relates to methodologies for significantly minimizing, if not entirely eliminating, the occurrence of voltage delay and irreversible Rdc growth in the about 35% to 70% DOD region by subjecting Li/SVO cells to novel discharge regimes. At the same time, the connected capacitors in the cardiac defibrillator are reformed to maintain them at their rated breakdown voltages.

Abstract: A hermetically sealed coin cell is described. The coin cell has the opposite polarity terminals isolated from one another by a glass-to-metal seal. Glassing a conductive disc inside a ring of greater diameter and height forms this seal. The height of the ring is equivalent to the desired height of the cell. The disc acts as one cell terminal, which can be positive or negative, and the ring serves as the other terminal. In plan view, both terminals are on the same side of the cell. This allows for easy mounting and connection to an electronic circuit board, and the like.

Abstract: A new cathode design has a first cathode active material of a relatively low energy density but of a relatively high rate capability contacted to the outer sides of first and second cathode current collectors and a second cathode active material having a relatively high energy density but of a relatively low rate capability in contact with the inner sides of the current collectors. The second cathode active material has a greater peripheral extend than the current collectors and the opposed layers of the first cathode active material between which it is sandwiched. This construction helps prevent delamination by promoting improved contact of the respective active materials to the current collectors. The present cathode design is useful for powering an implantable medical device requiring a high rate discharge application.

Abstract: An enclosure for an electrical energy storage device such as a wet tantalum electrolytic capacitor or an electrochemical cell such as a lithium/silver vanadium oxide cell is described. The enclosure comprises two metallic casing components or portions. The first is a drawn member having a planar face wall supporting a surrounding sidewall and is shaped to nest the anode, cathode and intermediate separator components. The surrounding sidewall has an annular flange at its outer periphery. A mating cover is a stamped planar piece of similar material whose periphery fits inside the annular flange or rim as a complementary piece.

Abstract: A lithium/fluorinated carbon electrochemical cell having the CFx material supported on a titanium current collector screen sputter coated with a noble metal is described. The gold, iridium, palladium, platinum, rhodium and ruthenium-coated titanium current collector provides the cell with higher rate capability, even after exposure to high temperatures, in comparison to cells of a similar chemistry having the CFx contacted to a titanium current collector painted with a carbon coating.

Abstract: A hermetically sealed coin cell is described. The coin cell has the opposite polarity terminals isolated from one another by a glass-to-metal seal. Glassing a conductive disc inside a ring of greater diameter and height forms this seal. The height of the ring is equivalent to the desired height of the cell. The disc acts as one cell terminal, which can be positive or negative, and the ring serves as the other terminal. In plan view, both terminals are on the same side of the cell. This allows for easy mounting and connection to an electronic circuit board, and the like.

Abstract: The present invention provides an electrochemical cell of either a primary or a secondary chemistry housed in a casing having opposed major side walls of a contoured shape.

Abstract: The present invention relates to a current collector for an electrochemical cell. The current collector is a substrate having a grid pattern comprising open areas converging at an imaginary focal point on a connector tab of the substrate. The openings are grouped into distinct regions with the larger openings immediately adjacent to the connector tab and the smaller openings distant there from. This provides more conductive pathways at greater distances from the tab.

Abstract: A unitary lid for the casing of an electrochemical energy storage device is described. The lid has a terminal lead ferrule and a fillport formed from a single blank in a machining process. The lid does not require any welding except for securing it to the open end of a casing container. This helps the lid contribute to the cell's volumetric efficiency, which is especially important for cells powering implantable medical device.

Abstract: A hermetically sealed coin cell is described. The coin cell has the opposite polarity terminals isolated from one another by a glass-to-metal seal. Glassing a conductive disc inside a ring of greater diameter and height forms this seal. The height of the ring is equivalent to the desired height of the cell. The disc acts as one cell terminal, which can be positive or negative, and the ring serves as the other terminal. In plan view, both terminals are on the same side of the cell. This allows for easy mounting and connection to an electric circuit board, and the like.

Abstract: It is known that reforming implantable defibrillator capacitors at least partially restores and preserves their charging efficiency. An industry-recognized standard is to reform implantable capacitors by pulse discharging the connected electrochemical cell about once every three months throughout the useful life of the medical device. A Li/SVO cell typically powers such devices. The present invention relates to methodologies for accurately determining the precise boundaries of voltage delay and irreversible Rdc growth region in the about 25% to 70% DOD region so that more frequent pulse discharging for the purpose of cell reform is confined to the limits of the region. At the same time, the connected capacitors in the cardiac defibrillator are reformed to maintain them at their rated breakdown voltages.

Abstract: The present invention provides an electrochemical cell of either a primary or a secondary chemistry housed in a casing having opposed major side walls of a contoured shape.

Abstract: A sintering method for valve metal powders, such as tantalum, niobium, aluminum, titanium, and their alloys, is described. The valve metal powders are pressed into a pellet and sintered at a relatively high temperature, but for a relatively short time. The anodized valve metal structure is then useful as an anode in an electrolytic capacitor.

Abstract: An economical method for manufacturing an electrode assembly of virtually any shape to fit into a similarly shaped casing without compromising volumetric efficiency is described. This is accomplished by providing an electrode assembly of multiplate anode and cathode plates that substantially match the internal shape of the casing. That way, no matter what shape the device being powered by the cell dictates the electrode assembly assumes, as little internal volume as possible is left unoccupied by electrode active materials.

Abstract: A method for providing a physician with an elective replacement indicator (ERI) for an implantable medical device is described. The medical device is powered by an electrochemical having a lithium anode coupled to a sandwich cathode comprising the configuration: SVO/current collector/CFx, with the SVO facing the anode. The indicator is predicated on when the cell's discharge capacity is nearing end-of-life (EOL) based on the theoretical capacity and the discharge efficiency of the SVO and CFx active materials. This serves as an indicator when it is time to replace the medical device.

Abstract: An insulator ring for preventing short circuit contact between the opposite polarity electrode in a case-terminal cell design is described. Typically, a lithium/silver vanadium oxide cell is built in a case-negative design with the casing serving at the negative terminal. The cathode is connected to an insulated terminal pin. In a conventional cell construction, the electrode assembly is enclosed in an insulator bag in addition to the electrode separator envelopes before being housed inside the casing. The insulator bag ensures the cathode electrode will not come into short circuit contact with the casing. In the present invention, the insulator bag is replaced with an insulator ring which only protects those portions of the electrode assembly vulnerable to short circuit contact.

Abstract: It is known that reforming implantable defibrillator capacitors at least partially restores and preserves their charging efficiency. An industry-recognized standard is to reform implantable capacitors by pulse discharging the connected electrochemical cell about once every three months throughout the useful life of the medical device. A Li/SVO cell typically powers such devices. The present invention relates to methodologies for significantly minimizing, if not entirely eliminating, the occurrence of voltage delay and irreversible Rdc growth in the about 25% to 70% DOD region by subjecting Li/SVO cells to novel discharge regimes. At the same time, the connected capacitors in the cardiac defibrillator are reformed to maintain them at their rated breakdown voltages.

Abstract: A rod-shaped coupler for connecting a current collector to a terminal pin, is described. The coupler is secured to the entire width of the current collector, preferably the cathode in a cell of a case negative design, and is generally aligned along the longitudinal axis of the electrode assembly. An extension portion of the coupler extends beyond the electrode assembly and is of a hollow, tubular structure crimped or otherwise collapsed into surrounding contact with the terminal pin. The coupler and terminal pin are then welded together. Preferably, the terminal pin is roughened prior to effecting the connection. This method of attachment is suitable for either primary lithium or secondary lithium ion cells, particularly those powering implantable biomedical devices.