Abstract:
An electrochemical cell comprising a medium rate electrode region intended to be discharged under a substantially constant drain and a high rate electrode region intended to be pulse discharged, is described. Both electrode regions share a common anode and are activated with the same electrolyte.
Abstract:
A separator insert used in addition to the main separator in an electrochemical cell, is described. A preferred material for the separator insert is a woven or nonwoven fluropolymeric material such as tetrafluoroethylene-ethylene copolymer (PETFE). This polymeric material is chemically inert to the components used in alkali metal cells, is corrosion resistant and does not decompose at normal battery temperatures. Preferably, the separator insert covers at least each side of the cathode means in a spirally wound electrode stack and extends less than one-half the total length thereof. This provides additional protection against internal short circuit conditions due to tearing or puncture of the traditional separator cause by exposed electrode screens.
Abstract:
A method for preparing a cathode, having as active material silver vanadium oxide with vanadium of mixed valance properties prepared using a sol-gel process, which may generate a preparation of silver vanadium oxide and which may provide an alternate preparation technique for improving chemical control in the formation of a cathode for incorporation into an electrochemical cell.
Abstract:
An electrochemical cell incorporating cathode materials comprising at least one metal oxide, a first metal and a second metal or a mixture of a first and a second metals or their metal oxides incorporated in the matrix of a host metal oxide is described. The cathode materials of this invention are constructed of the chemical addition, reaction, or otherwise intimate contact of various metal oxides and/or metal elements during thermal treatment in mixed states. The materials thereby produced contain metals and oxides of Group IB, IIB, IIIB, IVB, VB, VIB, VIIB, and VIII, which include the noble metals and/or their metal oxide compounds. A preferred material comprises a metal oxide matrix material formed of vanadium oxide and a copper-containing constituent and a silver-containing constituent.
Abstract:
A method for preparing a cathode having as active material silver vanadium oxide formed by chemical addition, reaction or otherwise intimate contact of a silver-containing component and a vanadium-containing compound to form a mixed metal oxide bronze that is thermally treated and rapidly cooled to form an amorphous product. The method of the present invention provides an alternate preparation technique for improving chemical control in the formation of a cathode for incorporation into an electrochemical cell.
Abstract:
An electrochemical cell incorporating cathode materials comprising at least one metal oxide, a first metal and a second metal or a mixture of a first and a second metals or their metal oxides incorporated in the matrix of a host metal oxide is described. The cathode materials of this invention are constructed of the chemical addition, reaction, or otherwise intimate contact of various metal oxides and/or metal elements during thermal treatment in mixed states. The materials thereby produced contain metals and oxides of Group IB, IIB, IIIB, IVB, VB, VIB, VIIB, and VIII, which include the noble metals and/or their metal oxide compounds. A preferred material comprises a composite metal oxide matrix formed as the thermal decomposition and reaction product of a matrix of vanadium oxide and at least two decomposable metals including copper and silver.
Abstract:
A fabric separator woven from synthetic halogenated polymeric fibers for use in an electrochemical cell comprising a Group IA, IIA and IIIB metal anode and a depolarizer/catholyte or a solid cathode/electrolyte system, is described. The separator is resistant to the highly oxidizing components present in the cell, is tear resistant and has a reduced thickness to minimize the diminishing effect of the separator on the volumetric amount of active components in the cell. The separator can be used by itself or as a laminate with a microporous film, preferably made of a fluoropolymeric fiber.
Abstract:
A method of making electrodes with distributed material loadings used in rechargeable electrochemical cells and batteries is described. This method controls electrode material loading (mass per unit area) along the electrode's length while maintaining uniform compaction throughout the electrode. Such prepared electrode maintain sufficient mechanical flexibility for winding and are compact and robust to have high energy density and long cycle life in rechargeable cells and batteries.
Abstract:
An electrochemical cell comprising a lithium anode, a cathode comprising a blank cut from a free-standing sheet of a silver vanadium oxide mixture contacted to a current collector. The active material has having a relatively lower surface area and an electrolyte activating the anode and the cathode is described. By optimizing the cathode active material surface area in a SVO-containing cell, the magnitude of the passivating film growth at the solid-electrolyte interphase (SEI) and its relative impermeability to lithium ion diffusion is reduced. Therefore, by using a cathode of an active material, in a range of from about 0.2 m2/gram to about 2.6 m2/gram, and preferably from about 1.6 m2/gram to about 2.4 m2/gram, it is possible to eliminate or significantly reduce undesirable irreversible Rdc growth and voltage delay in the cell and to extend its useful life in an 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.