Abstract: An alkaline cell having an anode comprising zinc, an aqueous alkaline electrolyte, a cathode mixture comprising cathode active material comprising copper oxide or copper hydroxide. Graphitic carbon, preferably expanded graphite or graphitic carbon nanofibers are added to the cathode mixture thereby resulting in a sharp drop in cathode resistivity. Addition of sulfur to cathode mixtures comprising copper hydroxide active material improves performance. The sharp drop in cathode resistivity resulting from the addition of expanded graphite or graphitic carbon nanofibers makes the cell suitable for use as a primary alkaline cell having good capacity. The graphitic carbon, preferably comprises preferably between about 3 and 10 percent by weight of the cathode. The carbon nanofibers have an average diameter desirably less than 500 nanometers, preferably between about 50 and 300 nanometers.

Abstract: A flat elongated alkaline battery comprising an outer metal housing and plurality of individual alkaline cells housed therein. The outer housing has at least a major surface which is a flat polygon. Preferably the outer metal housing is a cuboid. The individual cells comprise an anode slab comprising zinc, cathode slab, comprising manganese dioxide and separator therebetween. Each cell is formed by stacking the anode, separator, and cathode body to body. Each cell has at least one surface which is polygonal. The individual cells are preferably aligned in a row edge to edge to form a pack of cells having the same thickness as the thickness of an individual cell. The pack of cells are inserted into a common hydrogen permeable plastic container and encased therein. The cells encased in the plastic container are housed within the interior of the metal outer casing. The cells are electrically connected in parallel to the battery positive and negative terminals.

Abstract: An alkaline cell having an anode comprising zinc, an alkaline electrolyte solution, a separator, and a cathode comprising silver copper oxide AgCuO2, or Ag2Cu2O3, desirably in admixture with MnO2. The cathode preferably also includes a graphitic carbon to improve electrical conductivity. The graphtic carbon can comprise natural or synthetic graphites including expanded graphites and graphitic carbon fibers. The carbon nanofibers desirably have a mean average diameter less than 500 nanometers.

Abstract: An alkaline cell having an anode comprising zinc, an alkaline electrolyte solution, a separator, and a cathode comprising silver copper oxide selected from the compounds AgCuO2 Ag2Cu2O3 or any mixture thereof. The cathode preferably also includes a graphitic carbon to improve electrical conductivity. The graphitic carbon can comprise natural or synthetic graphites including expanded graphites and graphitic carbon fibers. The carbon nanofibers desirably have a mean average diameter less than 500 nanometers.

Abstract: An alkaline cell having an anode comprising zinc, an alkaline electrolyte solution, a separator, and a cathode comprising copper iodate. The cathode preferably also includes a graphitic carbon to improve electrical conductivity. The graphtic carbon can comprise natural or synthetic graphites including expanded graphites and graphitic carbon fibers. Preferably, the graphitic carbon comprises graphitic carbon nanofibers. The carbon nanofibers desirably have a mean average diameter less than 500 nanometers. The cathode can also include sulfur in admixture with the copper iodate to improve cell performance.

Abstract: A battery cartridge comprising a housing and one or more primary (nonrechargeable) cells therein. The cell can be a single primary cylindrical cell, desirably a primary lithium cell having a voltage of about 3.0 volts. Alternatively, there can be a pair or plurality of such cells electrically connected in parallel within the cartridge housing. The cartridge housing of the invention has an elongated body with an elongated opening in its surface of sufficient size to allow insertion of one or more cylindrical primary cells therein. The housing can be provided with a disk partition which divides the housing interior into two or more chambers, one for each cell. The cartridge can have overall dimensions similar to that of lithium ion or other rechargeable cartridges used to power small size camcorders or digital cameras. Thus, the battery cartridge of the invention has particular utility as a replacement for rechargeable cartridges for such devices.

Abstract: The invention provides an improved method for preparing homogeneous intermixtures of particulate manganese dioxide and conductive carbon for use in cathodes for electrochemical cells, in particular alkaline primary cells. Homogeneous intermixtures can be prepared by mechanically activating an essentially dry admixture of particulate electrolytic manganese dioxide and a natural graphite, an expanded graphite or combinations thereof with inert, rigid milling media by the agitation process of the invention. Improved cell discharge performance at both low and high rates of discharge can be achieved for extremely low levels of highly expanded graphite, typically between about 1 and 5 wt %.

Abstract: A spray method of applying liquid adhesive to surfaces of components of an electrochemical cell. The adhesive is applied by spraying through a nozzle, preferably activated by a piezoelectric transducer. The nozzle can be an elongated resilient tube terminating in an outlet opening. The adhesive is preferably sprayed in a pulsed stream of droplets. The liquid adhesive is desirably dispensed in fine droplets at a rate of between about 500 and 5000 droplets per second. The method is effective in applying adhesive to narrow width or difficult to reach surfaces of cell components in a precise, consistent and reproducible manner. In a specific application the adhesive can be applied to the narrow recessed step surrounding the terminal portion of the cathode casing of a zinc/air button cell. In such application the adhesive provides a tight seal between the cathode casing and cathode assembly, thereby preventing leakage of electrolyte from the cell.

Abstract: An alkaline electrochemical cell having a cathode comprising manganese dioxide and conductive graphitized mesophase pitch-based carbon fibers having an increased BET surface area of between about 10 and 60 m2/g, desirably between about 10 and 50 m2/g, preferably between about 30 and 50 m2/g by heat treatment between 800 and 1200° C. with potassium hydroxide. The treated graphitized mesophase pitch-based carbon fibers can comprise between about 1 and 100 percent by weight of the total graphite material in the cathode, typically between about 5 and 50 percent by weight of the total graphite. The total graphite in the cathode desirably comprises between about 4 and 10 percent by weight of the cathode. The graphite can be the mixtures of the graphitized mesophase pitch-based carbon fibers with flaky crystalline graphites including expanded graphites. The graphitized mesophase pitch-based carbon fibers have a mean average diameter typically between about 1 and 10 micron.

Abstract: A process for manufacture of manganese dioxide comprising subjecting an aqueous bath comprising manganese sulfate (MnSO4) and sulfuric acid (H2SO4) to electrolysis in a closed cell wherein the electrolysis bath is maintained at an elevated temperature above 110° C., preferably above 115° C. and at superatmospheric pressure. Desirably the bath can be maintained at an elevated temperature between about 115° C. and 155° C. The electrolysis is carried out preferably at elevated current density of between about 12.5 and 37 Amp/sq. ft (135 and 400 Amp/sq. meter) which allows for smaller or fewer electrolysis units. An MnO2 product having a specific surface area (SSA) within desired range of between 18-45 m2/g can be obtained. A doping agent, preferably a soluble titanium dopant is employed to help obtain the desired specific surface area (SSA) of the MnO2 product. The manganese dioxide product in zinc/MnO2 alkaline cells gives excellent service life, particularly in high power application.

Abstract: The invention relates to electrochemical cells having a metal current collector, particularly zinc/MnO2 primary alkaline cells wherein the cathode metal current collector is the cell's steel casing. The present invention is directed to a coating on the current collector, such as the inside surface of the steel casing of an alkaline cell, to improve the cell's performance, particularly when it is used for high power applications. In accordance with the invention the current collector or inside surface of the steel casing for the cell, is preferably preplated with nickel, then plated with a layer of cobalt or cobalt alloy, and subsequently coated with a layer of carbon over the cobalt layer. The carbon may be applied from a carbon/solvent coating mixture which is dried to evaporate the solvent carrier. The service life of the cell is improved, particularly during high power applications.

Abstract: A fluorosurfactant, preferably an anionic fluorosurfactant, can be added to the anode mixture of a zinc/air cell. A desirable surfactant is an anionic fluoroaliphaticcarboxylate. The addition of the surfactant reduces gassing and improves cell performance. The anode casing can also be treated with the surfactant solution prior to inserting the anode mixture therein. The anode casing of a zinc/air depolarized cell can also be heat treated after the casing has been formed but before anode material comprising zinc is inserted therein. The anode casing has a layer of copper on its inside surface. The process comprises heat treating the anode casing by passing a gas at a temperature between about 200° C. and 700° C., preferably between about 300° C. and 600° C. in contact therewith to form a heat treated anode casing and then cooling said heat treated anode casing to ambient temperature.

Abstract: A process for heat treating the metal sheeting forming the anode casing of a zinc/air depolarized cell before anode material comprising zinc is inserted into the anode casing. The anode casing has a layer of copper on its inside surface. The process comprises heat treating the metal sheeting forming the anode casing by passing a gas at a temperature between about 200° C. and 700° C., preferably between about 300° C. and 600° C. in contact therewith to form a heat treated sheeting and then cooling said heat treated sheeting to ambient temperature. The anode casing is stored away from atmospheric air until anode active material is inserted therein during cell assembly. The heat treating process significantly reduces gassing during cell discharge and storage. The cell's capacity and performance is improved when the cell's anode comprises particulate zinc (or zinc alloy) plated with indium, preferably between about 200 and 600 ppm indium.

Abstract: A casing for cylindrical electrochemical cells, for example, alkaline cells or lithium cells. The casing is characterized by having a non-uniform wall thickness. The casing comprises a cylindrical body surface, an open end and an integrally formed closed bottom. A portion of the casing body forms the peripheral edge of the casing at the open end thereof. The casing body surface has a wall thickness which is less than the wall thickness of the casing bottom. The casing has a peripheral edge which has a wall thickness which is greater than the wall thickness of the body surface. The peripheral edge wall thickness is desirably about the same or greater than the wall thickness of the casing bottom. The casing is formed by subjecting a sheet of metal to a series of discrete punching steps. A partially formed cup is punched through a die cavity in each step thereby progressively drawing the cup to a progressively reduced diameter and increased length.

Abstract: An electrochemical separator is formed insitu on an electrode surface within an electrochemical cell, preferably an alkaline cell cathode surface. The alkaline cell comprises a zinc anode, a and potassium hydroxide electrolyte. The cathode may comprise a cathode comprising manganese dioxide. The separator may be formed by coating an electrode surface preferably with a low molecular weight copolymer of polyvinyalcohol and polyvinylacetate. The film can be coagulated to form a permeable separator uniformly conforming to and covering the electrode surface irrespective of the shape and contour of the electrode. A separate protector disk can be inserted onto the top surface of the cathode to protect the cathode from shorting in the event that imperfections in the separator surface develop. The protector disk can have a protruding lip which surrounds and protects the inside corner edge of the cathode.

Abstract: An end seal assembly for small sized cylindrical alkaline cells. The seal assembly eliminates the need for a separate end cap and also eliminates the need for an insulating washer which is normally included between the end cap and housing at the cell's open end in order to insulate the end cap from the housing. The seal assembly includes an insulating sealing disk which fits into the open end of the cell housing. The peripheral edge of the cell housing is crimped over the edge of the sealing disk to seal the cell. The sealing disk comprises an integral raised central boss which protrudes from the housing open end. An elongated current collector penetrates into the cell's interior through an aperture in the central boss. The head of the current collector is thus exposed to the external environment and forms an end (negative) terminal for the cell. The boss is wider than normal in order to prevent interlocking with heads from other like cells.