Patents by Inventor Norikatsu Akutsu

Norikatsu Akutsu 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: 6114063
    Abstract: An alkaline storage battery comprises a positive electrode prepared by filling a nickel hydroxide in a porous plaque as an active material, a negative electrode, a separator and an alkaline electrolyte, the positive electrode containing the nickel hydroxide as a main component and a complex oxide of lithium and cobalt as a conductive agent. The lithium-cobalt complex oxide as a conductive agent is preferably represented by the formula Li.sub.x CoO.sub.2 (x is 0.2-0.9).
    Type: Grant
    Filed: March 4, 1998
    Date of Patent: September 5, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Masumi Katsumoto, Norikatsu Akutsu, Takeshi Yao, Yasuharu Yamamura
  • Patent number: 5879429
    Abstract: A method for producing a hydrogen storage alloy electrode comprising the step of treating a hydrogen storage alloy by immersing it in an alkaline solution containing cobalt ion or copper ion at a high temperature at a stage wherein the alloy is in powder state before formed into an electrode and/or at a stage wherein the alloy has been formed into an electrode. By this treatment, a hydrogen storage alloy electrode having an excellent high-rate discharge performance at a low temperature is obtained.
    Type: Grant
    Filed: March 26, 1997
    Date of Patent: March 9, 1999
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yasuharu Yamamura, Norikatsu Akutsu, Yoichi Izumi, Yoshio Moriwaki
  • Patent number: 5700596
    Abstract: The tap density of nickel hydroxide powders is improved, the expansion of a positive electrode is inhibited and the energy density of the positive electrode and the cycle life characteristics are improved by specifying the shape of the nickel hydroxide powders and besides, adding to the nickel hydroxide powders at least one of Cd, Ca, Zn, Mg, Fe, Co and Mn. The nickel hydroxide active material powders contain 1-7 wt % of at least one of Cd, Ca, Zn, Mg, Fe, Co and Mn and comprise a mixture of spherical or nearly spherical particles and non-spherical particles.
    Type: Grant
    Filed: November 21, 1991
    Date of Patent: December 23, 1997
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Munehisa Ikoma, Norikatsu Akutsu, Masashi Enokido, Fumihiko Yoshii, Hideo Kaiya, Shingo Tsuda
  • Patent number: 5547784
    Abstract: An alkaline storage battery made using a hydrogen-storing alloy for the negative electrode has suffered from the problems that the negative electrode is oxidized with oxygen gas generated from the positive electrode during overdischarge to cause increase of internal resistance and deterioration of charging and discharging cycle characteristics. Disclosed is a solution to the above problems which incorporates into the hydrogen-storing alloy negative electrode one of yttrium and yttrium compounds or a mixture thereof in such a state that it covers the surface of the hydrogen-storing alloy powder.
    Type: Grant
    Filed: November 25, 1994
    Date of Patent: August 20, 1996
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Takashi Okawa, Masashi Enokido, Shingo Tsuda, Norikatsu Akutsu
  • Patent number: 5466543
    Abstract: A nickel positive electrode for use in alkaline storage batteries which is improved in the rate of utilization of the nickel hydroxide in a wide temperature range with an oxygen evolving overvoltage being increased by incorporating at least one selected from the group consisting of compounds of yttrium, indium, antimony, barium and beryllium, and at least one selected from the group consisting of compounds of cobalt and calcium into the nickel positive electrode (2), and a nickel-hydrogen storage battery using the same.
    Type: Grant
    Filed: March 9, 1994
    Date of Patent: November 14, 1995
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Munehisa Ikoma, Kimie Muramatsu, Hiromu Matsuda, Norikatsu Akutsu, Isao Matsumoto