Patents by Inventor Reizo Maeda

Reizo Maeda 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).

  • Publication number: 20020001750
    Abstract: A metal hydride alkaline storage cell of the present invention comprises a positive electrode, a separator impregated with an electrolyte, and a negative electrode comprising hydrogen-absorbing alloy powder. On the surface of the hydrogen-absorbing alloy powder, there is formed a layer of hydrogen-absorbing alloy oxide, and on the layer of the oxide, there is dotted a catalytic metal or metal compound formed in a granular state by adding a substance soluble in the electrolyte. The substance is selected from the group consisting of a metal fluoride, a metal chloride, a metal iodide, and a metal sulfide. The proportion of the metal fluoride, the metal chloride, the metal iodide, or the metal sulfide in adding, is resticted within the range of from 0.1 to 2.5 wt. % based on the weight of hydrogen-absorbing alloy powder.
    Type: Application
    Filed: August 8, 2001
    Publication date: January 3, 2002
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Yoshinori Matsuura, Mitsuzo Nogami, Reizo Maeda, Katsuhiko Shinyama, Ikuo Yonezu, Koji Nishio
  • Patent number: 6333125
    Abstract: In a non-sintered nickel electrode for an alkaline storage cell, a discharge capacity and cycle life are improved. This is achieved by employing, as an active material for the non-sintered electrode, coated nickel active material particles, each of the particle comprising a base particle composed of nickel hydroxide and a Co—P—A layer coated on the base particle comprising Co and P and an element A, where A is at least one element selected from the group consisting of Mn, Zn, Ni, Y, and Bi.
    Type: Grant
    Filed: April 14, 1999
    Date of Patent: December 25, 2001
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Katsuhiko Shinyama, Yoshinori Matsuura, Reizo Maeda, Ikuo Yonezu, Koji Nishio
  • Patent number: 6322925
    Abstract: A metal hydride alkaline storage cell of the present invention comprises a positive electrode, a separator impregnated with an electrolyte, and a negative electrode comprising hydrogen-absorbing alloy powder. On the surface of the hydrogen-absorbing alloy powder, there is formed a layer of hydrogen-absorbing alloy oxide, and on the layer of the oxide, there is dotted a catalytic metal formed in a granular state by adding a substance soluble in the electrolyte. The substance is selected from the group consisting of a metal fluoride, a metal iodide, and a metal sulfide. The proportion of the metal fluoride, the metal iodide, or the metal sulfide in adding is restricted within the range of from 0.1 to 2.5 wt. % based on the weight of hydrogen-absorbing alloy powder. When the layer of the hydrogen-absorbing alloy oxide is formed on the surface of the hydrogen-absorbing alloy powder, the reaction area on the surface of the hydrogen-absorbing alloy is increased due to the roughness of the layer.
    Type: Grant
    Filed: August 27, 1998
    Date of Patent: November 27, 2001
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Yoshinori Matsuura, Mitsuzo Nogami, Reizo Maeda, Katsuhiko Shinyama, Ikuo Yonezu, Koji Nishio
  • Patent number: 6287725
    Abstract: The present electrode is fabricated by coating a conductive substrate with a paste including a hydrogen-absorbing alloy, a binder and a carbon material and sintering the conductive substrate coated with the paste under vacuum or in an atmosphere of a non-oxidizing gas. In this electrode, the carbon material works as a reducing agent so as to suppress oxidation of the hydrogen-absorbing alloy during the sintering, and therefore, the electrode exhibits large oxygen absorbing power in over-charge. Furthermore, the present battery uses, as a negative electrode, the sintered hydrogen-absorbing alloy electrode exhibiting large oxygen absorbing power in over-charge, and hence attains high reliability because increase of the pressure within the battery is minimal.
    Type: Grant
    Filed: February 1, 2000
    Date of Patent: September 11, 2001
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Reizo Maeda, Syuuichi Suzuki, Hiroshi Nakamura, Mitsuzo Nogami, Ikuo Yonezu, Koji Nishio
  • Patent number: 6077626
    Abstract: In an alkali storage battery comprising a positive electrode, a negative electrode and an alkali electrolyte in a battery can, .alpha.-nickel hydroxide containing manganese is used as a cathode active material for the positive electrode, and the difference between a charging potential and an oxygen gas evolution potential at the positive electrode is increased, to suppress oxygen gas evolution during the charging, and the volume percentage of the cathode active material and an anode active material is set to not less than 75% in the battery can, to obtain a large battery capacity.
    Type: Grant
    Filed: April 22, 1999
    Date of Patent: June 20, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Mitsuzou Nogami, Mutsumi Yano, Mitsunori Tokuda, Syuichi Suzuki, Shin Fujitani, Reizo Maeda, Ikuo Yonezu, Koji Nishio
  • Patent number: 6060195
    Abstract: In the non-sintered nickel electrode for an alkaline storage battery according to the present invention, the active material powder is made up of composite particles, each comprising a nickel hydroxide-containing core particle and a shell layer coating the nickel hydroxide-containing core particle, the shell layer containing a bismuth-containing compound, or is made up of composite particles, each comprising a nickel hydroxide-containing core particle, an inner shell layer coating the nickel hydroxide-containing core particle and an outer shell layer coating the inner shell layer, the inner shell layer containing a bismuth-containing compound and the outer shell layer containing cobalt metal, cobalt monoxide, cobalt hydroxide, cobalt oxyhydroxide or a sodium-containing cobalt compound prepared by adding an aqueous solution of sodium hydroxide to cobalt metal, cobalt monoxide, cobalt hydroxide or cobalt oxyhydroxide to obtain a mixture and heat-treating the mixture in the presence of oxygen.
    Type: Grant
    Filed: July 30, 1998
    Date of Patent: May 9, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Katsuhiko Shinyama, Reizo Maeda, Yoshinori Matsuura, Mitsuzo Nogami, Ikuo Yonezu, Koji Nishio
  • Patent number: 6057057
    Abstract: A conductive agent for use in alkaline storage batteries in accordance with one aspect of the present invention contains 0.1 to 10% by weight sodium. This sodium content results from cobalt or a cobalt compound, to which an aqueous solution of sodium hydroxide is added and heated to 50 to 200.degree. C. A non-sintered nickel electrode for use in alkaline storage batteries is also proposed. In this electrode, the aforesaid conductive agent in accordance with the present invention is added to a pulverulent active material consisting of grains of nickel hydroxide or grains mainly constituted by nickel hydroxide such that 1 to 20 parts by weight of the conductive agent is added to 100 parts by weight nickel hydroxide contained in the pulverulent active material. Another non-sintered nickel electrode for use in alkaline storage batteries is also proposed.
    Type: Grant
    Filed: February 6, 1997
    Date of Patent: May 2, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Mutsumi Yano, Mitsuzo Nogami, Katsuhiko Shinyama, Masao Inoue, Hiroshi Watanabe, Reizo Maeda, Ikuo Yonezu, Koji Nishio
  • Patent number: 5674643
    Abstract: A non-sintered nickel electrode for use in alkaline storage cells includes an active material comprising a solid solution of nickel hydroxide mixed with manganese, the solid solution further incorporating one or more elements selected from a group consisting of cobalt, cadmium, calcium and magnesium; an active material comprising a solid solution of nickel hydroxide mixed with manganese and zinc, the solid solution further incorporating one or more elements selected from a group consisting of cobalt, cadmium, calcium and magnesium; or an active material comprising nickel hydroxide with manganese added thereto, some of which manganese is incorporated in a solid solution of nickel hydroxide and the rest of which manganese exists as liberated from the solid solution of nickel hydroxide.
    Type: Grant
    Filed: February 12, 1996
    Date of Patent: October 7, 1997
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Mutsumi Yano, Mitsuzo Nogami, Reizo Maeda, Mamoru Kimoto, Shigekazu Yasuoka, Katsuhiko Shinyama, Koji Nishio, Toshihiko Saito