Abstract: A metal support disk useful in sealing an electrochemical cell exerts a resilient outward radial force against the seal to assure seal integrity over a wide temperature range and exerts an upward force against an adjacent metal end cap terminal to assure continued mechanical and electrical contact with the terminal. The support is a stepped disk having a centrally located, shallow, cylindrical pill-box, with the bottom of the pill-box extending radially outward into an annular ring. A spring means in the form of an S-shaped rim extends down from the periphery of the ring, terminating at its bottom in an outward extending flange. The edge of the flange presses a plastic seal member against the inside wall of the cell to form the seal.

Abstract: A method of making lithium manganese oxide of spinel structure is disclosed. The method involves the step of prelithiating a manganese oxide by reacting it with lithium hydroxide or lithium salt and then reacting the prelithiated manganese oxide in a second step at elevated temperature to form a lithium manganese oxide spinel. In a specific embodiment manganese dioxide powder is reacted with lithium hydroxide to prelithiate the manganese dioxide and the prelithiated manganese dioxide is separated from the reaction mixture and heated and reacted with lithium carbonate at elevated temperature to convert it to lithium manganese oxide spinel. The spinel product may be used advantageously in secondary (rechargeable) batteries.

Abstract: An electrochemical cell has a wheel shaped, molded plastic seal member of a unitary construction which includes a central cylindrical hub from which depend in outward radial sequence, an annular pressure vent, a boss, a downward projecting skirt, an annular flexure means for providing radial movement and an outer rim terminating at its periphery in a cylindrical wall. The pressure vent includes a thin membrane ring depending from the hub which joins the hub to an annular diaphragm. A hinge ring joins the periphery of the diaphragm to the boss. The seal member is designed so that the membrane ring fails primarily in shear at excessive cell pressure which makes the vent more reliable and easier to fabricate.

Abstract: A current interrupt mechanism for electrochemical cells is disclosed. A thermally activated current interrupt mechanism is integrated into an end cap assembly for an electrochemical cell. The thermally responsive mechanism preferably includes a free floating bimetallic disk which deforms when exposed to elevated temperature causing a break in an electrical pathway within the end cap assembly. This prevents current from flowing through the cell and effectively shuts down an operating cell. Alternatively, the thermally responsive mechanism may include a meltable mass of material which melts when exposed to elevated temperature to break an electrical pathway within the end cap assembly. The end cap assembly may also include integrated therein a pressure responsive current interrupt mechanism.

Abstract: The efficacy of a passivating layer in a rechargeable lithium ion cell is increased by heating the charged cell and storing the charged cell for a pre-determined period of time.

Abstract: A method of treating lithium manganese oxide of spinel structure is disclosed. The method involves heating the lithium manganese oxide spinel in an atmosphere of an inert gas which does not react with the spinel. Such gases may be selected advantageously from argon, helium, nitrogen, and carbon dioxide. Preferred nonreacting gases which may be employed for spinel treatment are nitrogen or carbon dioxide. The spinel is advantageously treated with such gases at elevated temperatures. Alternatively, the spinel may be first coated with a hydroxide, preferably lithium, sodium or potassium hydroxide and then heated in an atmosphere of carbon dioxide gas at elevated temperatures. Such treatment of lithium manganese oxide spinel has been determined to improve the performance of the spinel when employed as an electrode in rechargeable cells such as lithium-ion cells.

Abstract: A battery pack and a method of operating a battery system. The battery pack includes a rechargeable battery and a processor for monitoring the battery during charging and discharging. The processor receives data values representing the battery voltage, temperature and current, and the processor performs a series of calculations using those data values. The processor is part of a hybrid integrated circuit, which also includes an analog-to-digital converter, a ROM and a RAM. Preferably, the integrated circuit comprises a multitude of layers, upper layers of the circuit form the ROM, and lower layers of the circuit form the RAM.

Abstract: Disclosed is a process for treating manganese dioxide containing ion-exchangeable cations by replacing the ion-exchangeable cations present in the manganese dioxide with lithium by a process comprising first replacing ion-exchangeable cations present in the manganese dioxide with hydrogen. This readily is accomplished by slurrying the manganese dioxide in an aqueous acid solution. The resulting acidic manganese dioxide then is neutralized with a basic solution of a lithium containing compound, such as lithium hydroxide. This neutralization step serves to accomplish replacement of the previously introduced hydrogen, by ion-exchange, with lithium. The manganese dioxide then is washed with water, dried, and heat-treated at an elevated temperature, in conventional manner, to convert the gamma manganese dioxide to a mixture of the gamma and beta forms, which then is used as the active cathodic component in an electrochemical cell.

Abstract: Disclosed is a process for making a lithiated lithium manganese oxide spinel of the formula Li.sub.(1+x)Mn.sub.2 0.sub.4 comprising contacting a lithium manganese oxide spinel of the formula LiMn.sub.2 O.sub.4 with a lithium carboxylate compound, at a temperature and for a time sufficient to decompose the carboxylate compound and free the lithium to form said lithiated spinel.

Abstract: A current interrupt mechanism for electrochemical cells is disclosed. A thermally activated current interrupt mechanism is integrated into an end cap assembly for an electrochemical cell. The thermally responsive mechanism preferably includes a free floating bimetallic disk which deforms when exposed to elevated temperature causing a break in an electrical pathway within the end cap assembly. This prevents current from flowing through the cell and effectively shuts down an operating cell. Alternatively, the thermally responsive mechanism may include a meltable mass of material which melts when exposed to elevated temperature to break an electrical pathway within the end cap assembly. The end cap assembly may also include integrated therein a pressure responsive current interrupt mechanism.

Abstract: A battery pack and a method of operating a battery system. The battery pack includes a rechargeable battery and a processor for monitoring the battery during charging and discharging. The processor receives data values representing the battery voltage, temperature and current, and the processor performs a series of calculations using those data values. In one of these calculations, the processor determines the actual full capacity of the battery. Preferably, the processor also keeps track of an uncertainty value that represents an uncertainty in the capacity of the battery; and the processor calculates the actual full capacity of the battery at the end of each discharge cycle if, at that time, the uncertainty value is less than a given percentage of a nominal full capacity of the battery.

Abstract: A light transparent moisture barrier useful for preventing moisture from destroying the effectiveness of a moisture sensitive cell condition tester on an electrochemical cell comprises a plurality of very thin; alternating layers of an inorganic material and an organic material on a flexible, polymeric substrate. The layers are not laminated, but are formed on the substrate by a deposition or coating process and the thickness of any layer is less than 5 microns.

Abstract: Disclosed is a charger unit for charging a rechargeable energy storage device. In particular, a universal charger unit is disclosed which comprises a connector having a set of externally accessible contacts for making electrical contact with a corresponding set of receptor contacts on a rechargeable energy storage device. The connector, which may comprise a removable module, also preferably includes a sensor to interact with the structure of the receptor on the rechargeable device, so that the output of the charger unit can be regulated to be compatible with the electrical characteristics of the rechargeable device as determined by the sensor. The charger unit and/or connector may include one or more replaceable electronics modules.

Abstract: The present invention relates to coiled electrode assemblies having conductive tabs, methods of attaching the conductive tabs to the coiled electrode, and electrochemical cells employing such assemblies. In the process of the invention, the conductive tab area of an electrode plate coated with active material is pierced with opposing, offset piercing plates having raised surface probes which penetrate the conductive tab area. The resulting area is cleared of active material, and a conductive tab is welded to the thus treated area resulting in an electrode plate having a strong integrated tab assembly.

Abstract: A smart battery device which provides electrical power and which reports predefined battery parameters to an external device having a power management system, includes: at least one rechargeable cell connected to a pair of terminals to provide electrical power to an external device during a discharge mode and to receive electrical power during a charge mode, as provided or determined by the remote device; a data bus for reporting predefined battery identification and charge parameters to the external device; analog devices for generating analog signals representative of battery voltage and current at said terminals, and an analog signal representative of battery temperature at said cell; a hybrid integrated circuit (IC) having a microprocessor for receiving the analog signals and converting them to digital signals representative of battery voltage, current and temperature, and calculating actual charge parameters over time from the digital signals, the calculations including one calculation according to the f

Abstract: A rechargeable battery pack and a method of operating a rechargeable battery system. The battery pack includes a rechargeable battery, a processor for monitoring operation and performance of the battery, and a memory area for storing data values used by the processor. The memory area is normally powered by the battery, and a capacitor is provided to supply back-up power to the memory area in case of an interruption in the supply of electrical power to the memory area from the battery. The battery pack further includes a delatching circuit for electronically decoupling the memory area and the back-up capacitor from the battery under predetermined conditions.

Abstract: A battery pack and a method of operating a battery system. The battery pack includes a rechargeable battery and a processor for monitoring the battery during charging and discharging. The processor receives data values representing the battery voltage, temperature and current, and the processor performs a series of calculations using those data values. The processor has normal, standby and sleep modes. In the normal mode, the processor performs the series of calculations at first regular cycles, and in the standby mode, the processor performs the series of calculations at second regular cycles, which are longer than the first cycles. Preferably, the processor enters the standby mode when the battery current falls below a predetermined current level, and the processor enters the sleep mode when the battery voltage falls below a first predetermined voltage level.

Abstract: An apparatus for the transfer or conveyance of a slurry and the simultaneous densification thereof through the intermediary of vacuum pumping. Specifically, disclosed is an apparatus for the vacuum pumping of a slurry, particularly a zinc-containing slurry utilized in the preparation of zinc anodes for alkaline batteries, which facilitates the transfer of the slurry and the concurrent densification thereof in conjunction with the elimination of any gas bubbles which are entrapped in the slurry. Also disclosed is a method of transferring and simultaneously densifying a slurry while eliminating entrapped gas bubbles therefrom through the intermediary of a vacuum pumping process utilizing the disclosed apparatus.

Abstract: A method for the production of slurries which are uniform in density and consistency. In particular, a method for preparing zinc anode slurries employed in producing anodes for alkaline batteries. The method comprises a bag slurry forming process, using a drum mixer, involving mixing dry anode components within a sealed, inplated, gas-tight, liquid impervious, flexible, collapsible bag; and, then adding a wet component to the bag, collapsing said bag, and tumbling-kneading the components to form a blended slurry.

Abstract: A tester for determining the condition of an electrochemical power source, e.g. a battery or main cell, is disclosed. The tester may comprise an electrolytic (coulometric) cell connected in series to a auxiliary cell. The auxiliary cell is a miniature electrochemical power cell. The electrolytic (coulometric) cell may have no electromotive force of its own and may comprise an anode and cathode of the same material, desirably silver, with an electrolyte contacting at least a portion of both the anode and cathode. The tester may be permanently connected in parallel to a main cell being tested and is thin enough to be integratable into a label for the main cell. As the main cell discharges, the electrolytic cell anode clears proportionally to the discharge of one of the electrodes of the main cell to provide a continuous visually discernible indication of the state of charge of the main cell.