Patents by Inventor Akiko Fujino

Akiko Fujino 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: 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: 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: 7745042
    Abstract: A lithium ion secondary battery in which an abnormal overheat due to a short circuit of a current collecting portion of one electrode and an electrode material mixture of the other is prevented. The lithium ion secondary battery has: a positive electrode including a core material having a current collecting portion and a material mixture carrying portion and a material mixture layer carried thereon; a negative electrode including a core material having a current collecting portion and a material mixture carrying portion and a material mixture layer carried thereon; a separator and a porous electron-insulating layer including an inorganic oxide filler and a binder both interposed between the positive and negative electrodes; and a non-aqueous electrolyte. The insulating layer is carried on a region including surfaces of the positive electrode current collecting portion and material mixture layer, and/or a region including surfaces of the negative electrode current collecting portion and material mixture layer.
    Type: Grant
    Filed: December 28, 2004
    Date of Patent: June 29, 2010
    Assignee: Panasonic Corporation
    Inventors: Akiko Fujino, Tsumoru Ohata, 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
  • 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
  • Publication number: 20070202404
    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: Application
    Filed: April 26, 2007
    Publication date: August 30, 2007
    Applicant: 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: 20070196738
    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: Application
    Filed: April 26, 2007
    Publication date: August 23, 2007
    Applicant: 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: 20070196737
    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: Application
    Filed: April 26, 2007
    Publication date: August 23, 2007
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Takashi Takano, Shigeo Ikuta, Kohei Suzuki, Kouji Nishida, Masao Fukunaga, Akiko Fujino
  • Patent number: 7252689
    Abstract: By using a winding type electrode plate assembly resistant to displacement by wind-up and buckling, a lithium ion secondary battery, capable of suppressing deterioration in cycle and storage characteristic caused by expansion and shrinkage of the electrode plate due to charge/discharge cycles or by generation of gas during storage at high temperatures or the like, is accomplished. An electrode plate A comprising a binder mainly composed of a polymer material “a” and an electrode plate B, having the opposite polarity to the electrode plate A, with a porous polymer layer mainly composed of the polymer material “a” or a copolymer of the polymer material “a” formed thereon, are wound up in flat form to give a flat electrode plate assembly, which is soaked in a non-aqueous electrolyte and then heated and cooled, with the soaked state maintained, while pressure is applied in the direction of the thickness of the flat electrode plate assembly, to integrate the electrode plate assembly.
    Type: Grant
    Filed: March 5, 2003
    Date of Patent: August 7, 2007
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Akiko Fujino, Shinji Nakanishi, Hizuru Koshina
  • Publication number: 20070122715
    Abstract: A lithium ion secondary battery in which an abnormal overheat due to a short circuit of a current collecting portion of one electrode and an electrode material mixture of the other is prevented. The lithium ion secondary battery has: a positive electrode including a core material having a current collecting portion and a material mixture carrying portion and a material mixture layer carried thereon; a negative electrode including a core material having a current collecting portion and a material mixture carrying portion and a material mixture layer carried thereon; a separator and a porous electron-insulating layer including an inorganic oxide filler and a binder both interposed between the positive and negative electrodes; and a non-aqueous electrolyte. The insulating layer is carried on a region including surfaces of the positive electrode current collecting portion and material mixture layer, and/or a region including surfaces of the negative electrode current collecting portion and material mixture layer.
    Type: Application
    Filed: December 28, 2004
    Publication date: May 31, 2007
    Applicant: MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD.
    Inventors: Akiko Fujino, Tsumoru Ohata, Tetsuya Hayashi
  • Publication number: 20060281006
    Abstract: A lithium secondary battery includes: a positive electrode comprising a composite lithium oxide; a negative electrode comprising a material capable of absorbing and desorbing lithium; a separator interposed between the positive electrode and the negative electrode; and a non-aqueous electrolyte. The separator comprises non-woven fabric. At least one of the positive electrode and the negative electrode has a porous film that is adhered to a surface thereof, and the porous film comprises an inorganic oxide filler and a binder. The non-woven fabric preferably has a thickness of not less than 15 ?m and not more than 50 ?m. The non-woven fabric preferably has a melt-down temperature of 150° C. or more.
    Type: Application
    Filed: November 16, 2004
    Publication date: December 14, 2006
    Inventors: Akiko Fujino, Tsumoru Ohata
  • Publication number: 20060216608
    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: Application
    Filed: July 26, 2004
    Publication date: September 28, 2006
    Inventors: Tsumoru Ohata, Junji Nakajima, Tetsuya Hayashi, Takashi Takano, Shigeo Ikuta, Suzuki Kohei, Kouji Nishida, Masao Fukunaga, Akiko Fujino
  • Publication number: 20060194116
    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: Application
    Filed: September 13, 2004
    Publication date: August 31, 2006
    Inventors: Kohei Suzuki, Tsumoru Ohata, Junji Nakajima, Akiko Fujino, Shigeo Ikuta, Tetsuya Hayashi, Yusuke Fukumoto, Shinji Kasamatsu
  • Patent number: 6893778
    Abstract: In a lithium polymer battery of the present invention, a positive electrode, an negative electrode and a separator respectively contain a vinylidene fluoride-hexafluoropropylene copolymer, an electrolyte contains a solvent comprising diethyl carbonate and a solute dissolved in the solvent, and the electrolyte further contains diphenyl ether as an additive. With the use of the above electrolyte, it is possible to improve the thermal stability of the battery containing P(VDF-HFP) in the positive electrode, the negative electrode and the separator and to operate the shutdown function surely, thereby ensuring the excellent safety of the battery.
    Type: Grant
    Filed: February 20, 2002
    Date of Patent: May 17, 2005
    Assignee: Matsushita Electric Industrial Co., Ltd.
    Inventors: Akiko Fujino, Shinji Mino, Hiroshi Yoshizawa
  • Publication number: 20050095505
    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: Application
    Filed: October 27, 2004
    Publication date: May 5, 2005
    Inventors: Tsumoru Ohata, Shigeo Ikuta, Akiko Fujino, Tetsuya Hayashi, Kohei Suzuki