Patents by Inventor Thomas L. Dunham

Thomas L. Dunham has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5397658
    Abstract: A pre-form of an anode current collector for an alkaline electrochemical cell is plated at its edges with tin, zinc, or a combination of tin and zinc, to protect the anode current collector from chemically reacting with the anode paste, and forming hydrogen gas in the cell. The anode current collector, thus protected, is placed in an alkaline electrochemical cell with an anode paste preferably containing no mercury, without incurring deleterious swelling of the resulting cell.
    Type: Grant
    Filed: August 16, 1993
    Date of Patent: March 14, 1995
    Assignee: Rayovac Corporation
    Inventor: Thomas L. Dunham
  • Patent number: 5278006
    Abstract: An alkaline electrochemical cell is disclosed which comprises a cathode subassembly, with a metal oxide cathode and collector means for collecting current from the cathode, a zinc anode, an electrolyte in contact with the zinc anode and a nonmetallic separator between the cathode and the anode. The collector means comprises a metal plated current collector additionally plated with a layer of palladium, rhodium or platinum. In one embodiment, the metal oxide cathode is a manganese dioxide cathode and the current collector comprises a nickel plated steel clip adapted for holding the metal oxide cathode which has been plated with an additional layer of palladium, rhodium or platinum on surfaces where the collector makes contact with the cathode.
    Type: Grant
    Filed: April 11, 1991
    Date of Patent: January 11, 1994
    Inventor: Thomas L. Dunham
  • Patent number: 4925754
    Abstract: An alkaline electrochemical cell is disclosed which comprises a cathode subassembly, with a metal oxide cathode and collector means for collecting current from the cathode, a zinc anode, an electrolyte in contact with the zinc anode and a nonmetallic separator between the cathode and the anode. The collector means comprises a metal plated current collector additionally plated with a layer of palladium. In one embodiment, the metal oxide cathode is a manganese dioxide cathode and the current collector comprises a nickel plated steel clip adapted for holding the metal oxide cathode which has been plated with an additional layer of palladium on surfaces where the clip makes strong gripping contact with the metal oxide cathode. Most preferably, the current collector clip is selectively plated on the inner surface of each leg of the clip with a palladium layer about 3 microinches thick.
    Type: Grant
    Filed: June 1, 1989
    Date of Patent: May 15, 1990
    Assignee: Rayovac Corporation
    Inventor: Thomas L. Dunham