Patents by Inventor Hiromasa Yagi

Hiromasa Yagi 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: 6887511
    Abstract: A method for preparing an electrode material for a lithium battery, characterized in that a noncrystalline silicon thin film that serves as an active material is deposited on a substrate.
    Type: Grant
    Filed: October 20, 2000
    Date of Patent: May 3, 2005
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masaki Shima, Hiromasa Yagi, Hisaki Tarui, Hiroaki Ikeda, Masahisa Fujimoto, Shin Fujitani, Yoichi Domoto
  • Patent number: 6844113
    Abstract: The electrode for a lithium secondary battery includes: a current collector; an interlayer containing Mo or W provided on the current collector; and a thin film composed of active material capable of lithium storage and release deposited on the interlayer.
    Type: Grant
    Filed: April 11, 2002
    Date of Patent: January 18, 2005
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hiromasa Yagi, Hisaki Tarui
  • Patent number: 6815003
    Abstract: A method for fabricating an electrode for lithium secondary battery formed by depositing a thin film composed of active material capable of lithium storage and release, on a metallic foil to be used as a current collector, in which the surface of the metallic foil is roughened through wet-etching and then the thin film is deposited on the roughened surface.
    Type: Grant
    Filed: November 29, 2001
    Date of Patent: November 9, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hiromasa Yagi, Koji Endo, Hisaki Tarui, Hiroshi Okano, Shingo Nakano
  • Patent number: 6770175
    Abstract: An apparatus, for forming an electrode for a lithium secondary cell capable of readily forming an active material layer constituted by at least two elements and controlling the composition of the active material layer, comprises a first sputtering source for sputtering a first material forming the active material layer onto the surface of the collector and a second sputtering source for sputtering a second material forming the active material layer onto the surface of the collector. Plasma regions of the first and second sputtering sources are arranged to overlap each other. The active material layer constituted by at least two elements is readily formed with excellent reproducibility, and its composition can be readily controlled by independently controlling power applied to the first sputtering source and the second sputtering source.
    Type: Grant
    Filed: April 16, 2002
    Date of Patent: August 3, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Yoichi Domoto, Hisaki Tarui, Hiromasa Yagi
  • Patent number: 6764791
    Abstract: A rechargeable lithium battery using an Li alloying metal as the active material of at least one of its positive and negative electrodes. The metal active material is covered with a thin film which is nonreactive with Li ions, permits passage of Li ions but does not have an Li ion conductivity.
    Type: Grant
    Filed: July 16, 2001
    Date of Patent: July 20, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Noriyuki Tamura, Masahisa Fujimoto, Maruo Kamino, Shin Fujitani, Hiromasa Yagi, Yoichi Domoto, Hisaki Tarui, Ryuji Ohshita, Ikuo Yonezu
  • Publication number: 20040072067
    Abstract: A lithium secondary battery comprising an electrode in which an active material layer which includes an active material that electrochemically occludes and releases lithium is formed on a current collector, wherein cracks are formed in the active material layer by occlusion and release of lithium ions and thereafter a solid electrolyte is formed in the cracks in the active material layer.
    Type: Application
    Filed: September 30, 2003
    Publication date: April 15, 2004
    Inventors: Hiroshi Minami, Katsunobu Sayama, Hiromasa Yagi, Atsushi Fukui, Mariko Torimae, Yasuyuki Kusumoto, Hisaki Tarui
  • Publication number: 20040048161
    Abstract: A nonaqueous electrolyte rechargeable battery using molybdenum oxide in the form of thin film deposited on an aluminum-containing substrate, as a positive electrode material.
    Type: Application
    Filed: December 23, 2002
    Publication date: March 11, 2004
    Inventors: Takuya Sunagawa, Hiroaki Ikeda, Yoichi Domoto, Masahisa Fujimoto, Ryuji Ohshita, Masaki Shima, Hiromasa Yagi, Hisaki Tarui, Shin Fujitani
  • Patent number: 6685804
    Abstract: A method for fabricating an electrode for a rechargeable lithium battery which includes depositing a thin film composed of active material capable of alloy formation with lithium on a current collector made of a metal incapable of alloy formation with lithium, by using a process for depositing a thin film by supplying a material from a gas phase, characterized in that the thin film of active material is deposited at such a temperature that enables formation of a mixed layer via diffusion of a constituent of the current collector into the thin film in the vicinity of an interface therebetween.
    Type: Grant
    Filed: April 19, 2002
    Date of Patent: February 3, 2004
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hiroaki Ikeda, Yoichi Domoto, Hiromasa Yagi, Hisaki Tarui, Masahisa Fujimoto, Shin Fujitani, Masaki Shima
  • Patent number: 6649033
    Abstract: The method for producing an electrode for a lithium secondary battery, having an active material in the form of a thin film composed of an interface layer formed on a current collector and an active material layer formed on the interface layer. The method comprises the steps of: depositing the interface layer on the current collector by sputtering; and depositing the active material layer on the interface layer by vapor evaporation.
    Type: Grant
    Filed: March 27, 2002
    Date of Patent: November 18, 2003
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hiromasa Yagi, Hisaki Tarui
  • Publication number: 20030138554
    Abstract: A method for manufacturing an electrode for a lithium secondary battery includes a step of forming an oxide film other than a natural oxide film on a current collector by oxidizing the surface of the current collector, and a step of forming an active material layer on the oxide film by a method to provide a material for the active material layer by emitting in the vapor phase, such as PVD (physical vapor deposition) including sputtering, vapor evaporation, and the like, and CVD (chemical vapor deposition) including plasma CVD.
    Type: Application
    Filed: January 17, 2003
    Publication date: July 24, 2003
    Inventors: Hiromasa Yagi, Hisaki Tarui
  • Patent number: 6534131
    Abstract: A method for treating a carbon film comprising, in sequence, depositing a carbon film onto a substrate by a plasma CVD technique and exposing the carbon film at its surface to a gas plasma produced utilizing at least one type of gas selected from an Ar gas, N2 gas, H2 gas and F-containing gas so that the carbon film surface is modified.
    Type: Grant
    Filed: February 14, 2001
    Date of Patent: March 18, 2003
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Yoichi Domoto, Hiromasa Yagi
  • Publication number: 20030038024
    Abstract: The method for producing an electrode for a lithium secondary battery, having an active material in the form of a thin film composed of an interface layer formed on a current collector and an active material layer formed on the interface layer. The method comprises the steps of: depositing the interface layer on the current collector by sputtering; and depositing the active material layer on the interface layer by vapor evaporation.
    Type: Application
    Filed: March 27, 2002
    Publication date: February 27, 2003
    Inventors: Hiromasa Yagi, Hisaki Tarui
  • Publication number: 20020177044
    Abstract: The electrode for a lithium secondary battery includes: a current collector; an interlayer containing Mo or W provided on the current collector; and a thin film composed of active material capable of lithium storage and release deposited on the interlayer.
    Type: Application
    Filed: April 11, 2002
    Publication date: November 28, 2002
    Inventors: Hiromasa Yagi, Hisaki Tarui
  • Publication number: 20020175069
    Abstract: An apparatus for forming an electrode for a lithium secondary cell capable of readily forming an active material layer constituted by at least two elements and controlling the composition of the active material layer is obtained. The apparatus for forming an electrode for a lithium secondary cell comprises a first sputtering source for sputtering a first material forming the active material layer onto the surface of the collector and a second sputtering source for sputtering a second material forming the active material layer onto the surface of the collector. Plasma regions of the first and second sputtering sources are arranged to overlap with each other. Thus, the active material layer constituted by at least two elements is readily formed with excellent reproducibility. When power applied to the first sputtering source and the second sputtering source is controlled independently of each other, the composition of the active material layer constituted by at least two elements is readily controlled.
    Type: Application
    Filed: April 16, 2002
    Publication date: November 28, 2002
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Yoichi Domoto, Hisaki Tarui, Hiromasa Yagi
  • Publication number: 20020102348
    Abstract: A method for fabricating an electrode for lithium secondary battery formed by depositing a thin film composed of active material capable of lithium storage and release, on a metallic foil to be used as a current collector, in which the surface of the metallic foil is roughened through wet-etching and then the thin film is deposited on the roughened surface.
    Type: Application
    Filed: November 29, 2001
    Publication date: August 1, 2002
    Inventors: Hiromasa Yagi, Koji Endo, Hisaki Tarui, Hiroshi Okano, Shingo Nakano
  • Publication number: 20020034687
    Abstract: A rechargeable lithium battery using an Li alloying metal as the active material of at least one of its positive and negative electrodes. The metal active material is covered with a thin film which is nonreactive with Li ions, permits passage of Li ions but does not have an Li ion conductivity.
    Type: Application
    Filed: July 16, 2001
    Publication date: March 21, 2002
    Inventors: Noriyuki Tamura, Masahisa Fujimoto, Maruo Kamino, Shin Fujitani, Hiromasa Yagi, Yoichi Domoto, Hisaki Tarui, Ryuji Ohshita, Ikuo Yonezu