Abstract: An end cap assembly is disclosed for sealing the open end of a cylindrical alkaline cell housing preferably having a diameter less than the diameter of AAA size cells. The end cap assembly is preferably intended for sealing AAAA (LR61) size cylindrical alkaline cells. The end cap assembly comprises a terminal end cap, an insulating sealing disk underlying said end cap, and an elongated current collector penetrating through an aperture in said insulating sealing disk. At least a portion of the insulating sealing disk lies within the cell housing to seal the open end thereof. The terminal end cap has a peripheral edge, preferably formed from a curved rib, which is locked within the peripheral edge of the insulating sealing disk. The end cap assembly does not require other metal disks held within the sealing and insulating disk. The insulating disk comprises a discontinuous skirt comprising a plurality of integral legs emanating downwardly into the cell interior from the peripheral edge of said insulating disk.

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 or shape memory alloy member 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. The thermally responsive mechanism may include a heat producing electrical resistance means, preferably a Zener diode, to enhance thermal sensitivity. The end cap assembly may include a pressure responsive mechanism which ruptures when there is extreme gas pressure buildup. Gas is allowed to escape from the cell interior to the external environment through a series of vent apertures within the end cap assembly.

Abstract: An end cap assembly is disclosed for sealing the open end of a cylindrical alkaline cell housing preferably having a diameter less than the diameter of AAA size cells. The end cap assembly is preferably intended for sealing AAAA (LR61) size cylindrical alkaline cells. The end cap assembly comprises a terminal end cap, an insulating sealing disk underlying said end cap, and an elongated current collector penetrating through an aperture in said insulating sealing disk. At least a portion of the insulating sealing disk lies within the cell housing to seal the open end thereof. The terminal end cap is located outside of said housing. The end cap assembly may include an insulating washer between the terminal end cap and the cell housing. The terminal end cap and the insulating washer are stacked over the peripheral edge of the cell housing at the open end of the cell housing. The insulating washer electrically insulates the terminal end cap from the cell housing.

Abstract: A current interrupt assembly for electrochemical cells is disclosed. The current interrupter assembly may be a self-contained, sealed unit which may be separately inserted into the cell during cell construction. Several current interrupt assemblies may be inserted in the cell. The current interrupter assembly has particular utility for thin rechargeable cells and when inserted in the cell forms a portion of the electrical pathway between a cell electrode and corresponding terminal. The current interrupt mechanism comprises a thin thermally responsive member preferably comprising a disk of a shape memory metal alloy having a curved surface. The current interrupt mechanism may include a heat producing electrical resistance means, preferably a Zener diode in proximity to the thermally responsive member. When cell temperature exceeds a predetermined value the disk deflects to cause a break in the electrical pathway within the assembly.

Abstract: An end cap assembly for an electrochemical cell, for example an alkaline cell, is disclosed comprising an exposed terminal end cap of single piece construction having a convoluted surface, an electrically insulating member and a metal support disk between the insulating member and the terminal end cap. The end cap assembly is inserted into the open end of the cell housing after the cell contents have been supplied. A portion of the end cap surface is a flat annular step which improves contact between the end cap and the electrically conductive portion of a condition tester for the cell which may be integrated into the cell label. The annular step is advantageously located at about right angle to the cell's longitudinal axis. The surface step is integral with the end cap and preferably located at about the same level as the shoulder of the cell housing at the end of the cell containing the end cap. The end cap assembly as a whole provides a tight seal for the cell.

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 layers of amorphous silicon nitride and a hydrophobic fluorocarbon polymer on a flexible, polymeric substrate. The layers are formed on the substrate by a deposition process such as sputtering. The thickness of any individual layer is less than one micron.

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 or shape memory alloy member 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. The end cap assembly may include a pressure responsive mechanism which ruptures when there is extreme gas pressure buildup. Gas is allowed to escape from the cell interior to the external environment through a series of vent apertures within the end cap assembly.

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: An improved high rate alkaline cell is obtained by employing an anode current collector comprising a foraminous metal.

Abstract: A package for articles such as zinc air batteries includes a base, a cover hinged to the base, and a flexible sheet material for covering the articles. The base includes pockets for the articles. The flexible sheet material adhesively attached to the articles and base, covers the articles in the pockets. The articles are capable of being stripped from the flexible sheet material.

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, e.g, argon, helium, nitrogen or carbon dioxide, which does not react with the spinel. Alternatively, the spinel may be first coated with an alkali metal hydroxide, preferably lithium, sodium or potassium hydroxide and then heated in an atmosphere preferably containing carbon dioxide. Such treatment of lithium manganese oxide spinel improves the performance of the spinel when employed as an electrode in rechargeable cells such as lithium-ion cells. Alternatively, the spinel may be first treated in an aqueous solution of a soluble metal salt of a carboxylic acid prior to treatment with heated carbon dioxide or inert gas. In such latter case the spinel may optionally also be treated with an alkali metal hydroxide prior to treatment with carbon dioxide or inert gas.

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.