Patents by Inventor Tsutomu Ohzuku

Tsutomu Ohzuku 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: 20080032199
    Abstract: In a non-aqueous electrolyte secondary battery comprising: a negative electrode containing, as a negative electrode active material, at least a material capable of absorbing and desorbing lithium ions or metal lithium; a positive electrode; and an electrolyte, an oxide containing nickel and manganese elements, the material comprising primary particles of the oxide having a twining portion and a superlattice arrangement of a [3×3] R30° when assigned as R3-m is used as a positive electrode active material.
    Type: Application
    Filed: August 3, 2007
    Publication date: February 7, 2008
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
  • Publication number: 20070231705
    Abstract: A non-aqueous electrolyte secondary battery including a unit cell including a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte, the positive electrode capacity being greater than the negative electrode capacity, and at least a portion of the non-aqueous electrolyte is gasified during charging.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 4, 2007
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa
  • Publication number: 20070207383
    Abstract: The present invention relates to a positive electrode active material comprising a lithium-containing composite oxide containing nickel with an oxidation state of 2.0 to 2.5 and manganese with an oxidation state of 3.5 to 4.0, the oxidation state determined by the shifts of energy at which absorption maximum is observed in the X-ray absorption near-K-edge structures, and to a non-aqueous electrolyte secondary battery using the same, the positive electrode active material being characterized in having a high capacity, a long storage life and excellent cycle life.
    Type: Application
    Filed: May 1, 2007
    Publication date: September 6, 2007
    Applicant: Osaka City University
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
  • Publication number: 20070009424
    Abstract: A positive electrode active material for a non-aqueous electrolyte battery comprising a lithium-containing transition metal oxide, produced with the use of a dry precursor obtained by: introducing an alkaline solution together with an aqueous solution containing two or more of transition metal salts or two kinds or more of aqueous solutions of different transition metal salts into a reaction vessel to obtain a hydroxide or an oxide as a precursor through coprecipitation with a reductant being coexistent or an inert gas being supplied; and drying the precursor at 300 to 500° C. to obtain a dry precursor.
    Type: Application
    Filed: September 14, 2006
    Publication date: January 11, 2007
    Applicants: OSAKA CITY UNIVERSITY, MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
  • Publication number: 20060275664
    Abstract: In order to provide a 3V level non-aqueous electrolyte secondary battery with a flat voltage and excellent cycle life at a high rate with low cost, the present invention provides a positive electrode represented by the formula: Li2±?[Me]4O8?x, wherein 0??<0.4, 0?x<2, and Me is a transition metal containing Mn and at least one selected from the group consisting of Ni, Cr, Fe, Co and Cu, said active material exhibiting topotactic two-phase reactions during charge and discharge.
    Type: Application
    Filed: May 11, 2006
    Publication date: December 7, 2006
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama, Hizuru Koshina
  • Publication number: 20060204847
    Abstract: As an alternative technique to lead-acid batteries, the present invention provides an inexpensive 2 V non-aqueous electrolyte secondary battery having excellent cycle life at a high rate by preventing volume change during charge and discharge. The non-aqueous electrolyte secondary battery uses: a positive electrode active material having a layered structure, being represented by chemical formula Li1±?[Me]O2, where 0??<0.2, and Me is a transition metal including Ni and at least one selected from the group consisting of Mn, Fe, Co, Ti and Cu, and including elemental nickel and elemental cobalt in substantially the same ratio; and a negative electrode active material including Li4Ti5O12 (Li1/3Ti5/3]O4).
    Type: Application
    Filed: May 10, 2006
    Publication date: September 14, 2006
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Kensuke Nakura
  • Publication number: 20050170250
    Abstract: In order to provide a 3V level non-aqueous electrolyte secondary battery with a flat voltage and excellent cycle life at a high rate with low cost, the present invention provides a positive electrode represented by the formula: Li2±?[Me]4O8?x, wherein 0??<0.4, 0?x<2, and Me is a transition metal containing Mn and at least one selected from the group consisting of Ni, Cr, Fe, Co and Cu, said active material exhibiting topotactic two-phase reactions during charge and discharge.
    Type: Application
    Filed: February 24, 2003
    Publication date: August 4, 2005
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama, Hizuru Koshina
  • Publication number: 20050147889
    Abstract: As an alternative technique to lead-acid batteries, the present invention provides an inexpensive 2 V non-aqueous electrolyte secondary battery having excellent cycle life at a high rate by preventing volume change during charge and discharge. The non-aqueous electrolyte secondary battery uses: a positive electrode active material having a layered structure, being represented by chemical formula Li1±?[Me]O2, where 0??<0.2, and Me is a transition metal including Ni and at least one selected from the group consisting of Mn, Fe, Co, Ti and Cu, and including elemental nickel and elemental cobalt in substantially the same ratio; and a negative electrode active material including Li4Ti5O12(Li[Li1/3Ti5/3]O4).
    Type: Application
    Filed: November 3, 2004
    Publication date: July 7, 2005
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Kensuke Nakura
  • Publication number: 20050079416
    Abstract: A nonaqueous electrolytic secondary cell produced at low cost and having a large capacity comprises a negative electrode having an active material mainly composed of a material that at least absorbs and releases lithium ions or metallic lithium, a positive electrode, and an electrolyte. The active material of the positive electrode is an oxide containing nickel, manganese, and cobalt, and the contents of the elements are substantial the same.
    Type: Application
    Filed: April 15, 2002
    Publication date: April 14, 2005
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
  • Publication number: 20040126660
    Abstract: In a non-aqueous electrolyte secondary battery comprising: a negative electrode containing, as a negative electrode active material, at least a material capable of absorbing and desorbing lithium ions or metal lithium; a positive electrode; and an electrolyte, an oxide containing nickel and manganese elements, the material comprising primary particles of the oxide having a twining portion and a superlattice arrangement of a [{square root}{square root over ( )}3×{square root}{square root over ( )}3] R30° when assigned as R3-m is used as a positive electrode active material.
    Type: Application
    Filed: July 30, 2003
    Publication date: July 1, 2004
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
  • Publication number: 20040058243
    Abstract: To provide a non-aqueous electrolyte secondary battery in which the amount of Li deposited is small and the battery surface temperature does not increase so much, a positive electrode active material comprising crystal particles of an oxide having a layered single-phase crystal structure and a composition represented by the formula (1): LiNi2/3Mn1/3O2, wherein the arrangement of oxygen atoms constituting the oxide is a cubic close-packed structure is used.
    Type: Application
    Filed: July 7, 2003
    Publication date: March 25, 2004
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
  • Publication number: 20030170540
    Abstract: The present invention provides a high-capacity and low-cost non-aqueous electrolyte secondary battery, comprising: a negative electrode containing, as a negative electrode active material, a ssubstance capable of absorbing/desorbing lithium ions and/or metal lithium; a separator; a positive electrode; and an electrolyte, wherein the positive electrode active material contained in the positive electrode is composed of crystalline particles of an oxide containing two kinds of transition metal elements, the crystalline particles having a layered crystal structure, and oxygen atoms constituting the oxide forming a cubic closest packing structure.
    Type: Application
    Filed: January 17, 2003
    Publication date: September 11, 2003
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
  • Publication number: 20030087154
    Abstract: The present invention relates to a positive electrode active material comprising a lithium-containing composite oxide containing nickel with an oxidation state of 2.0 to 2.5 and manganese with an oxidation state of 3.5 to 4.0, the oxidation state determined by the shifts of energy at which absorption maximum is observed in the X-ray absorption near-K-edge structures, and to a non-aqueous electrolyte secondary battery using the same, the positive electrode active material being characterized in having a high capacity, a long storage life and excellent cycle life.
    Type: Application
    Filed: October 23, 2002
    Publication date: May 8, 2003
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
  • Patent number: 6551744
    Abstract: The present invention discloses a non-aqueous electrolyte secondary battery comprising: a negative electrode containing metallic lithium or a substance at least capable of absorbing/desorbing lithium ion; a separator; a positive electrode; and an electrolyte, wherein the active material for the positive electrode comprises an oxide containing nickel element and manganese element in substantially the same atomic ratios. The non-aqueous electrolyte secondary battery thus fabricated is low cost in construction and has a high capacity.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: April 22, 2003
    Assignees: Matsushita Electric Industrial Co., Ltd., Osaka City Government, Tanaka Chemical Corporation
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama
  • Publication number: 20030054251
    Abstract: A positive electrode active material for a non-aqueous electrolyte battery comprising a lithium-containing transition metal oxide, produced with the use of a dry precursor obtained by: introducing an alkaline solution together with an aqueous solution containing two or more of transition metal salts or two kinds or more of aqueous solutions of different transition metal salts into a reaction vessel to obtain a hydroxide or an oxide as a precursor through coprecipitation with a reductant being coexistent or an inert gas being supplied; and drying the precursor at 300 to 500° C. to obtain a dry precursor.
    Type: Application
    Filed: September 12, 2002
    Publication date: March 20, 2003
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tsutomu Ohzuku, Hiroshi Yoshizawa, Masatoshi Nagayama