Patents by Inventor Shigeo Ikuta

Shigeo Ikuta 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: 8211574
    Abstract: A lithium ion secondary battery includes a positive electrode capable of absorbing and desorbing lithium ion, a negative electrode capable of absorbing and desorbing lithium ion, a porous film interposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte, the porous film being adhered to a surface of at least the negative electrode. The porous film includes an inorganic filler and a first binder: The content of the first binder in the porous film is 1.5 to 8 parts by weight per 100 parts by weight of the filler: The first binder includes a first rubber including an acrylonitrile unit: The first rubber is water-insoluble and has a decomposition temperature of 250° C. or higher. The negative electrode includes a negative electrode active material capable of absorbing and desorbing lithium ion and a second binder, and the second binder includes a second rubber particle and a water-soluble polymer.
    Type: Grant
    Filed: September 13, 2004
    Date of Patent: July 3, 2012
    Assignee: Panasonic Corporation
    Inventors: Kohei Suzuki, Tsumoru Ohata, Junji Nakajima, Akiko Fujino, Shigeo Ikuta, Tetsuya Hayashi, Yusuke Fukumoto, Shinji Kasamatsu
  • Patent number: 8163424
    Abstract: A secondary battery includes: a positive electrode; a negative electrode; a porous electron-insulating layer adhered to a surface of at least one selected from the group consisting of the positive electrode and the negative electrode; and an electrolyte. The porous electron-insulating layer comprises a particulate filler and a resin binder, and the particulate filler comprises an indefinite-shape particle comprising a plurality of primary particles that are joined to one another. A neck is preferably formed between the primary particles. Since the porous electron-insulating layer has high porosity, it is possible to obtain a secondary battery that exhibits excellent low-temperature characteristics, which are particularly important in actual use, and that is capable of discharging at a large current.
    Type: Grant
    Filed: February 7, 2005
    Date of Patent: April 24, 2012
    Assignee: Panasonic Corporation
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Shigeo Ikuta, Yusuke Fukumoto
  • Patent number: 8163425
    Abstract: A secondary battery includes: a positive electrode; a negative electrode; a porous electron-insulating layer adhered to a surface of at least one selected from the group consisting of the positive electrode and the negative electrode; and an electrolyte. The porous electron-insulating layer comprises a particulate filler and a resin binder, and the particulate filler comprises an indefinite-shape particle comprising a plurality of primary particles that are joined to one another. A neck is preferably formed between the primary particles. Since the porous electron-insulating layer has high porosity, it is possible to obtain a secondary battery that exhibits excellent low-temperature characteristics, which are particularly important in actual use, and that is capable of discharging at a large current.
    Type: Grant
    Filed: June 20, 2008
    Date of Patent: April 24, 2012
    Assignee: Panasonic Corporation
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Shigeo Ikuta, Yusuke Fukumoto
  • Patent number: 8119291
    Abstract: A non-aqueous electrolyte secondary battery including: a positive electrode; a negative electrode; a separator interposed between the positive electrode and the negative electrode; a non-aqueous electrolyte; and a porous insulating film adhered to a surface of at least one selected from the group consisting of the positive electrode and the negative electrode, the porous insulating film including an inorganic oxide filler and a film binder, wherein the ratio R of actual volume to apparent volume of the separator is not less than 0.4 and not greater than 0.7, and wherein the ratio R and a porosity P of the porous insulating film satisfy the relational formula: ?0.10?R?P?0.30.
    Type: Grant
    Filed: April 29, 2008
    Date of Patent: February 21, 2012
    Assignee: Panasonic Corporation
    Inventors: Kaoru Inoue, Kiyomi Kato, Kohei Suzuki, Shigeo Ikuta, Yusuke Fukumoto, Tetsuya Hayashi
  • Patent number: 8003259
    Abstract: A non-aqueous electrolyte secondary battery including: a positive electrode; a negative electrode; a separator interposed between the positive electrode and the negative electrode; a non-aqueous electrolyte; and a porous insulating film adhered to a surface of at least one selected from the group consisting of the positive electrode and the negative electrode, the porous insulating film including an inorganic oxide filler and a film binder, wherein the ratio R of actual volume to apparent volume of the separator is not less than 0.4 and not greater than 0.7, and wherein the ratio R and a porosity P of the porous insulating film satisfy the relational formula: ?0.10?R?P?0.30.
    Type: Grant
    Filed: April 29, 2008
    Date of Patent: August 23, 2011
    Assignee: Panasonic Corporation
    Inventors: Kaoru Inoue, Kiyomi Kato, Kohei Suzuki, Shigeo Ikuta, Yusuke Fukumoto, Tetsuya Hayashi
  • Patent number: 7931983
    Abstract: A lithium ion secondary battery includes a positive electrode capable of absorbing and desorbing lithium ion, a negative electrode capable of absorbing and desorbing lithium ion, a porous film interposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte: the porous film being adhered to a surface of at least one of the positive electrode and the negative electrode; the porous film including a filler and a resin binder; the resin binder content in the porous film being 1.5 to 8 parts by weight per 100 parts by weight of the filler; and the resin binder including an acrylonitrile unit, an acrylate unit, or a methacrylate unit.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: April 26, 2011
    Assignee: Panasonic Corporation
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Takashi Takano, Shigeo Ikuta, Kohei Suzuki, Kouji Nishida, Masao Fukunaga, Akiko Fujino
  • Patent number: 7816038
    Abstract: A method for producing a lithium ion secondary battery includes the steps of: forming a positive electrode mixture layer on a positive electrode substrate to obtain a positive electrode; forming a negative electrode mixture layer on a negative electrode substrate to obtain a negative electrode; forming an electronically insulating porous film that is bonded to a surface of at least one of the positive electrode and the negative electrode; interposing a separator between the positive electrode and the negative electrode to form an electrode plate assembly; and impregnating the electrode plate assembly with a non-aqueous electrolyte. The step of forming a porous film includes the steps of: preparing a porous film paste that contains a film binder comprising a thermo-cross-linkable resin and a particulate filler; and applying the porous film paste onto a surface of at least one of the positive electrode and the negative electrode and heating the resultant applied film.
    Type: Grant
    Filed: April 19, 2005
    Date of Patent: October 19, 2010
    Assignee: Panasonic Corporation
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Shigeo Ikuta, Akiko Fujino, Eitaro Nakamura
  • Publication number: 20100188048
    Abstract: A nonaqueous secondary battery includes a negative electrode plate 303 containing a negative electrode active material 324 capable of reversely inserting and extracting lithium, a positive electrode plate 301 containing lithium as a positive electrode active material 322, an electrolyte, a porous protective membrane 325 provided between the negative electrode plate 303 and the positive electrode plate 301 and permeable to lithium ions while having heat resistance, and a concave portion 352 in which growth of deposited metal, which is formed according to a set voltage Vs, is controlled in such a manner that the deposited metal is bridged between the negative electrode plate 303 and the positive electrode plate 301 when the set voltage Vs is applied between the negative electrode plate 303 and the positive electrode plate 301.
    Type: Application
    Filed: May 21, 2008
    Publication date: July 29, 2010
    Inventors: Hajime Nishino, Kohei Suzuki, Shigeo Ikuta, Akiko Fujino
  • Patent number: 7759004
    Abstract: Disclosed is an electrode for lithium ion secondary batteries which includes an active material layer containing active material particles and a porous insulating layer formed on the surface of the active material layer. The porous insulating layer includes an inorganic filler and a resin binder, and the surface of the active material layer has a first region on which the porous insulating layer is formed, and a second region on which the porous insulating layer is not formed. By using such an electrode, a lithium ion secondary battery can have a high capacity, excellent characteristics and improved safety.
    Type: Grant
    Filed: December 1, 2004
    Date of Patent: July 20, 2010
    Assignee: Panasonic Corporation
    Inventors: Shigeo Ikuta, Tsumoru Ohata
  • Patent number: 7758998
    Abstract: A lithium ion secondary battery includes a positive electrode capable of absorbing and desorbing lithium ion, a negative electrode capable of absorbing and desorbing lithium ion, a porous film interposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte: the porous film being adhered to a surface of at least one of the positive electrode and the negative electrode; the porous film including a filler and a resin binder; the resin binder content in the porous film being 1.5 to 8 parts by weight per 100 parts by weight of the filler; and the resin binder including an acrylonitrile unit, an acrylate unit, or a methacrylate unit.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: July 20, 2010
    Assignee: Panasonic Corporation
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Takashi Takano, Shigeo Ikuta, Kohei Suzuki, Kouji Nishida, Masao Fukunaga, Akiko Fujino
  • Patent number: 7754377
    Abstract: A lithium ion secondary battery includes a positive electrode capable of absorbing and desorbing lithium ion, a negative electrode capable of absorbing and desorbing lithium ion, a porous film interposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte: the porous film being adhered to a surface of at least one of the positive electrode and the negative electrode; the porous film including a filler and a resin binder; the resin binder content in the porous film being 1.5 to 8 parts by weight per 100 parts by weight of the filler; and the resin binder including an acrylonitrile unit, an acrylate unit, or a methacrylate unit.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: July 13, 2010
    Assignee: Panasonic Corporation
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Takashi Takano, Shigeo Ikuta, Kohei Suzuki, Kouji Nishida, Masao Fukunaga, Akiko Fujino
  • Patent number: 7560193
    Abstract: In a secondary battery including a positive electrode, a negative electrode and a porous film bonded to the surface of at least one of the positive electrode and the negative electrode, the porous film includes ceramic particles and a binder, and the ceramic particles include polycrystalline particles obtained by mechanically crushing a fired material comprising a ceramic that is directly synthesized from a ceramic precursor. The porous film has a porosity of 40 to 80%, for example. The porous film can be formed by a method including the steps of: obtaining a fired material comprising a ceramic from a ceramic precursor; obtaining ceramic particles by mechanically crushing the fired material of the ceramic; obtaining a slurry including the ceramic particles and a binder; and applying the slurry onto the surface of an electrode, followed by drying.
    Type: Grant
    Filed: December 22, 2005
    Date of Patent: July 14, 2009
    Assignee: Panasonic Corporation
    Inventors: Shigeo Ikuta, Yusuke Fukumoto
  • Publication number: 20080274399
    Abstract: A secondary battery includes: a positive electrode; a negative electrode; a porous electron-insulating layer adhered to a surface of at least one selected from the group consisting of the positive electrode and the negative electrode; and an electrolyte. The porous electron-insulating layer comprises a particulate filler and a resin binder, and the particulate filler comprises an indefinite-shape particle comprising a plurality of primary particles that are joined to one another. A neck is preferably formed between the primary particles. Since the porous electron-insulating layer has high porosity, it is possible to obtain a secondary battery that exhibits excellent low-temperature characteristics, which are particularly important in actual use, and that is capable of discharging at a large current.
    Type: Application
    Filed: June 20, 2008
    Publication date: November 6, 2008
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO. LTD.
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Shigeo Ikuta, Yusuke Fukumoto
  • Publication number: 20080254369
    Abstract: A non-aqueous electrolyte secondary battery including: a positive electrode; a negative electrode; a separator interposed between the positive electrode and the negative electrode; a non-aqueous electrolyte; and a porous insulating film adhered to a surface of at least one selected from the group consisting of the positive electrode and the negative electrode, the porous insulating film including an inorganic oxide filler and a film binder, wherein the ratio R of actual volume to apparent volume of the separator is not less than 0.4 and not greater than 0.7, and wherein the ratio R and a porosity P of the porous insulating film satisfy the relational formula: ?0.10?R?P?0.30.
    Type: Application
    Filed: April 29, 2008
    Publication date: October 16, 2008
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Kaoru Inoue, Kiyomi Kato, Kohei Suzuki, Shigeo Ikuta, Yusuke Fukumoto, Tetsuya Hayashi
  • Patent number: 7435507
    Abstract: A lithium ion secondary battery has an electrode group including: a winding core; and a positive electrode and a negative electrode that are wound around the winding core. This electrode group does not have an independent separator between the positive and negative electrodes. A porous film is integrally formed on both sides of at least one of the positive electrode and the negative electrode. The negative electrode and the positive electrode are connected to the winding core by a negative electrode resin film and a positive electrode resin film, respectively. The use of such resin films makes it possible to reduce the breakage of the porous films and prevent a short-circuit between the positive and negative electrodes.
    Type: Grant
    Filed: October 27, 2004
    Date of Patent: October 14, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tsumoru Ohata, Shigeo Ikuta, Akiko Fujino, Tetsuya Hayashi, Kohei Suzuki
  • Publication number: 20080248394
    Abstract: A non-aqueous electrolyte secondary battery including: a positive electrode; a negative electrode; a separator interposed between the positive electrode and the negative electrode; a non-aqueous electrolyte; and a porous insulating film adhered to a surface of at least one selected from the group consisting of the positive electrode and the negative electrode, the porous insulating film including an inorganic oxide filler and a film binder, wherein the ratio R of actual volume to apparent volume of the separator is not less than 0.4 and not greater than 0.7, and wherein the ratio R and a porosity P of the porous insulating film satisfy the relational formula: ?0.10?R?P?0.30.
    Type: Application
    Filed: April 29, 2008
    Publication date: October 9, 2008
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Kaoru Inoue, Kiyomi Kato, Kohei Suzuki, Shigeo Ikuta, Yusuke Fukumoto, Tetsuya Hayashi
  • Patent number: 7422825
    Abstract: A non-aqueous electrolyte secondary battery including: a positive electrode; a negative electrode; a separator interposed between the positive electrode and the negative electrode; a non-aqueous electrolyte; and a porous insulating film adhered to a surface of at least one selected from the group consisting of the positive electrode and the negative electrode, the porous insulating film including an inorganic oxide filler and a film binder, wherein the ratio R of actual volume to apparent volume of the separator is not less than 0.4 and not greater than 0.7, and wherein the ratio R and a porosity P of the porous insulating film satisfy the relational formula: ?0.10?R?P?0.30.
    Type: Grant
    Filed: March 22, 2005
    Date of Patent: September 9, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Kaoru Inoue, Kiyomi Kato, Kohei Suzuki, Shigeo Ikuta, Yusuke Fukumoto, Tetsuya Hayashi
  • Patent number: 7402184
    Abstract: In a secondary battery including a positive electrode, a negative electrode and a porous film bonded to the surface of at least one of the positive electrode and the negative electrode, the porous film includes ceramic particles and a binder, and the ceramic particles include polycrystalline particles obtained by mechanically crushing a fired material comprising a ceramic that is directly synthesized from a ceramic precursor. The porous film has a porosity of 40 to 80%, for example. The porous film can be formed by a method including the steps of: obtaining a fired material comprising a ceramic from a ceramic precursor; obtaining ceramic particles by mechanically crushing the fired material of the ceramic; obtaining a slurry including the ceramic particles and a binder; and applying the slurry onto the surface of an electrode, followed by drying.
    Type: Grant
    Filed: January 19, 2007
    Date of Patent: July 22, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Shigeo Ikuta, Yusuke Fukumoto
  • Patent number: 7396612
    Abstract: A lithium ion secondary battery includes a positive electrode capable of absorbing and desorbing lithium ion, a negative electrode capable of absorbing and desorbing lithium ion, a porous film interposed between the positive electrode and the negative electrode, and a non-aqueous electrolyte: the porous film being adhered to a surface of at least one of the positive electrode and the negative electrode; the porous film including a filler and a resin binder; the resin binder content in the porous film being 1.5 to 8 parts by weight per 100 parts by weight of the filler; and the resin binder including an acrylonitrile unit, an acrylate unit, or a methacrylate unit.
    Type: Grant
    Filed: July 26, 2004
    Date of Patent: July 8, 2008
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Takashi Takano, Shigeo Ikuta, Kohei Suzuki, Kouji Nishida, Masao Fukunaga, Akiko Fujino
  • Publication number: 20080038639
    Abstract: A method for producing a lithium ion secondary battery includes the steps of: forming a positive electrode mixture layer on a positive electrode substrate to obtain a positive electrode; forming a negative electrode mixture layer on a negative electrode substrate to obtain a negative electrode; forming an electronically insulating porous film that is bonded to a surface of at least one of the positive electrode and the negative electrode; interposing a separator between the positive electrode and the negative electrode to form an electrode plate assembly; and impregnating the electrode plate assembly with a non-aqueous electrolyte. The step of forming a porous film includes the steps of: preparing a porous film paste that contains a film binder comprising a thermo-cross-linkable resin and a particulate filler; and applying the porous film paste onto a surface of at least one of the positive electrode and the negative electrode and heating the resultant applied film.
    Type: Application
    Filed: April 19, 2005
    Publication date: February 14, 2008
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Shigeo Ikuta, Akiko Fujino, Eitaro Nakamura