Patents by Inventor Kohji Yuasa

Kohji Yuasa 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: 20010033966
    Abstract: The present invention provides a positive electrode material for alkaline storage batteries which has high energy density and causes little capacity reduction even when a charge/discharge cycle is repeated at high temperatures. The positive electrode material for alkaline storage batteries of the present invention comprises nickel hydroxide particles and a layers of cobalt oxide coating the nickel hydroxide particles. A valence of cobalt of the cobalt oxide is larger than 3.0, and the cobalt oxide contains sodium ions or potassium ions inside the crystal and further fixes lithium hydroxide or lithium ions.
    Type: Application
    Filed: December 29, 2000
    Publication date: October 25, 2001
    Applicant: Matsushita Electric Industrial Co., Ltd
    Inventors: Futoshi Tanigawa, Akihiro Maeda, Yasushi Nakamura, Yoichi Izumi, Yoshitaka Dansui, Kohji Yuasa
  • Publication number: 20010024751
    Abstract: A alkaline storage battery using positive electrodes comprising an active material containing nickel hydroxide particles and a rare earth element or a compound thereof containing or mixed with 0.1-100 ppm of Fe or an Fe compound based on the rare earth element or the compound thereof is provided.
    Type: Application
    Filed: February 28, 2001
    Publication date: September 27, 2001
    Inventors: Tatsuhiko Suzuki, Yoshitaka Dansui, Hideki Kasahara, Kohji Yuasa
  • Patent number: 6218046
    Abstract: The present invention provides a positive electrode material for alkaline storage batteries which has high energy density and causes little capacity reduction even when a charge/discharge cycle is repeated at high temperatures. The positive electrode material for alkaline storage batteries of the present invention comprises nickel hydroxide particles and a layers of cobalt oxide coating the nickel hydroxide particles. A valence of cobalt of the cobalt oxide is greater than 3.0, and the cobalt oxide contains sodium ions or potassium ions inside the crystal and further fixes lithium hydroxide or lithium ions.
    Type: Grant
    Filed: September 2, 1998
    Date of Patent: April 17, 2001
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Futoshi Tanigawa, Masumi Katsumoto, Fumio Kato, Tatsuhiko Suzuki, Yoshitaka Dansui, Kohji Yuasa
  • Patent number: 6130008
    Abstract: An alkaline storage battery with improved cycle life and self-discharge characteristics is disclosed. The battery comprises a positive electrode, a negative electrode, a separator and an alkaline electrolyte. For the separator, a material of a woven or nonwoven fabric sheet or a porous film of polyolefine resin of which surfaces have been modified with a hydrophilic compound having a carboxyl group by graft-polymerization. The quantity of carbonates inside the battery is regulated to 150 mg/Ah battery capacity. The quantity of carbonates inside the battery can be regulated to a minimum by optimizing graft polymerization and subsequent washing conditions.
    Type: Grant
    Filed: January 29, 1998
    Date of Patent: October 10, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kohji Yuasa, Yasuhiro Nitta, Kaori Gomikawa
  • Patent number: 6083642
    Abstract: Disclosed is a positive electrode material which provides an alkaline storage battery having high active material utilization, wherein good capacity recovery can be obtained by charging even after standing in the state of overdischarge or short circuit, and reduction in capacity scarcely arises. This active material comprises nickel hydroxide particles and a cobalt oxide. The cobalt oxide is a higher cobalt oxide containing as a main component .gamma.-cobalt oxyhydroxide, which belongs to any one crystal system of hexagonal, orthorhombic and monoclinic systems and has a layered structure, wherein a lattice spacing of the (003) plane is from 5.5 to 7.0 angstroms and an average valence of cobalt is higher than 3.0. Those which are prepared by coating the surface of nickel hydroxide particles with the higher cobalt oxide are preferable.
    Type: Grant
    Filed: December 16, 1997
    Date of Patent: July 4, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Fumio Kato, Futoshi Tanigawa, Yoshitaka Dansui, Kohji Yuasa
  • Patent number: 6074785
    Abstract: The present invention provides a nickel/metal hydride storage battery using improved nickel hydroxide with an increased energy density as the active material. This invention is characterized in that the nickel hydroxide as the active material of the positive electrode constituting the battery indispensably contains as a solid solution at least one transition metal selected from the group consisting of Mn, Cr and Co in a proportion of 2 to 20 atomic % based on the amount of the nickel hydroxide in terms of metallic nickel, and that the crystal structure of the nickel hydroxide at charged state is a hexagonal or tetragonal system which has a diffraction peak of 2.theta. on (00l) plane of .beta.-NiOOH at an angle of approximately 15.degree. to 19.degree. in X-ray diffraction using CuK.alpha. as a source and has a regular array with a NaCl type structure.
    Type: Grant
    Filed: April 10, 1998
    Date of Patent: June 13, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshitaka Dansui, Fumio Kato, Kenji Suzuki, Kohji Yuasa
  • Patent number: 6033805
    Abstract: By using a thin film-formed positive electrode, and negative electrode and a film separator, the capacity density of the electrode plate can be improved and at the same time a nickel-hydrogen secondary battery with a higher capacity can be easily obtained; as a result a nickel-hydrogen secondary battery with a higher capacity density can be provided.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: March 7, 2000
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Yoshitaka Dansui, Kenji Suzuki, Kohji Yuasa
  • Patent number: 5346781
    Abstract: Disclosed is an alkaline storage battery, in which the negative electrode is constituted by a hydrogen absorbing alloy capable of absorbing/desorbing hydrogen electrochemically, and a hydrophobic material is provided in the space between the surface of the negative electrode and the separator while a hydrophilic material is provided in the inside of the negative electrode, thereby properly secure both wetting property and surface hydrophobic property of the negative electrode against the alkaline electrolytic solution. Accordingly, a hydrogen gas generated in charging the battery can be absorbed by a vapor phase reaction in the hydrophobic portion in the surface of the negative electrode which is exposed to the vapor phase and can be absorbed electrochemically in the portion of the negative electrode which is wetted by the electrolytic solution, so that the inner pressure of the battery can be reduced to thereby make it possible to perform quick charging.
    Type: Grant
    Filed: January 28, 1991
    Date of Patent: September 13, 1994
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kohji Yuasa, Munehisa Ikoma, Hiroshi Kawano, Osamu Takahashi, Isao Matsumoto
  • Patent number: 5250369
    Abstract: Disclosed is an alkaline storage battery, in which the negative electrode is constituted by a hydrogen absorbing alloy capable of absorbing/desorbing hydrogen electrochemically, and a hydrophobic material is provided in the space between the surface of the negative electrode and the separator while a hydrophilic material is provided in the inside of the negative electrode, thereby properly secure both wetting property and surface hydrophobic property of the negative electrode against the alkaline electrolytic solution. Accordingly, a hydrogen gas generated in charging the battery can be absorbed by a vapor phase reaction in the hydrophobic portion in the surface of the negative electrode which is exposed to the vapor phase and can be absorbed electrochemically in the Portion of the negative electrode which is wetted by the electrolytic solution, so that the inner pressure of the battery can be reduced to thereby make it possible to perform quick charging.
    Type: Grant
    Filed: September 28, 1992
    Date of Patent: October 5, 1993
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kohji Yuasa, Munehisa Ikoma, Hiroshi Kawano, Osamu Takahashi, Isao Matsumoto
  • Patent number: 5034289
    Abstract: Disclosed is an improvement in a negative electrode of an alkaline storage battery, in which the negative electrode is constituted by a hydrogen absorbing alloy capable of absorbing/desorbing hydrogen electrochemically, and a hydrophobic material and a hydrophilic material are provided in a portion of the surface layer of the negative electrode and in the side of the negative electrode respectively so as to properly secure both the wetting property and hydrophobic property of the negative electrode against the alkaline electrolytic solution. Accordingly, a hydrogen can be absorbed electrochemically in the portion of the negative electrode which is wetted by the electrolytic solution and a hydrogen gas generated in charging the battery can be absorbed by a vapor phase reaction in the hydrophobic portion of the negative electrode which is exposed to the vapor phase so that the internal gas pressure can be reduced to thereby make it possible to perform rapid charging.
    Type: Grant
    Filed: May 24, 1989
    Date of Patent: July 23, 1991
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kohji Yuasa, Munehisa Ikoma, Hiroshi Kawano, Osamu Takahashi, Isao Matsumoto
  • Patent number: 4994334
    Abstract: Disclosed is an alkaline storage battery using a negative electrode formed of a hydrogen absorbing alloy capable of absorbing/desorbing hydrogen electrochemically. A three-dimensional structural matter having hydrophobic property is used as a supporter for supporting the hydrogen absorbing alloy of the negative electrode, so that hydrophobic property is given to the surface of the hydrogen absorbing alloy which is in contact with the support, whereby a hydrogen gas generated in a charging period is absorbed by powder of the alloy exposed at a gas phase portion to suppress the increase of the internal gas pressure of the battery.According to the present invention, it is possible to perform rapid charge in a short time because the increase of the internal gas pressure of the battery can be suppressed.
    Type: Grant
    Filed: May 24, 1989
    Date of Patent: February 19, 1991
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Munehisa Ikoma, Yasuko Ito, Kohji Yuasa, Isao Matsumoto, Takashi Hino