Patents by Inventor Hironori Shirakata

Hironori Shirakata 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: 9337479
    Abstract: [Problem] To provide a nonaqueous electrolyte secondary battery exhibiting superior stability characteristics and having charge/discharge characteristics exhibiting a high-rate discharge stroke, even when a lithium-nickel-cobalt manganate and a spinel-type lithium manganate are used as the positive electrode active material. [Solution] A mixture having a specific ratio of a tungsten- and zirconium-modified lithium-nickel-cobalt manganate and a spinel-type lithium manganate is used as the positive electrode active material. Furthermore, a nonaqueous electrolyte having a specific ratio of the content of dimethyl carbonate and the content of a cyclic carbonate is used.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: May 10, 2016
    Assignee: SANYO Electric Co., Ltd.
    Inventors: Shinya Miyazaki, Hironori Shirakata
  • Patent number: 8802298
    Abstract: A non-aqueous electrolyte secondary cell having high temperature storage characteristics and cycle characteristics is provided. This object is realized by adopting the following configuration. The non-aqueous electrolyte secondary cell includes a positive electrode having a positive electrode active material; a negative electrode having a negative electrode active material; and a non-aqueous electrolyte having a non-aqueous solvent and an electrolyte salt. And the positive electrode active material contains a compound represented by Lia(NibCocMnd)1?x?yWxZryO2 (0.9?a?1.2, 0.3?b?0.6, 0.1?c?0.7, 0?d?0.4, b+c+d=1, 0.001?x?0.05, 0.001?y?0.05); and the non-aqueous electrolyte contains at least one compound selected from the group consisting of cyclohexylbenzene, tert-butylbenzene and tert-amylbenzene in a total concentration of 0.1 to 5% by mass relative to the mass of the non-aqueous electrolyte.
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: August 12, 2014
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Shinya Miyazaki, Hironori Shirakata
  • Patent number: 8568928
    Abstract: A non-aqueous electrolyte secondary battery has a positive electrode (1), a negative electrode (2), and a non-aqueous electrolyte. The positive electrode has a positive electrode mixture layer containing a positive electrode active material, a binder agent, and a conductive agent. The positive electrode active material in the positive electrode mixture layer contains an olivine-type lithium-containing metal phosphate represented by the general formula LixMPO4, where M is at least one element selected from the group consisting of Co, Ni, Mn, and Fe, and x is 0<x<1.3. The conductive agent in the positive electrode mixture layer is composed of a mixture of carbon particles and carbon fiber.
    Type: Grant
    Filed: October 19, 2007
    Date of Patent: October 29, 2013
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hironori Shirakata, Koji Hasumi, Hiroyuki Akita, Kazunori Donoue, Yoshinori Kida
  • Publication number: 20130260262
    Abstract: [Problem] To provide a nonaqueous electrolyte secondary battery exhibiting superior stability characteristics and having charge/discharge characteristics exhibiting a high-rate discharge stroke, even when a lithium-nickel-cobalt manganate and a spinel-type lithium manganate are used as the positive electrode active material. [Solution] A mixture having a specific ratio of a tungsten- and zirconium-modified lithium-nickel-cobalt manganate and a spinel-type lithium manganate is used as the positive electrode active material. Furthermore, a nonaqueous electrolyte having a specific ratio of the content of dimethyl carbonate and the content of a cyclic carbonate is used.
    Type: Application
    Filed: December 9, 2011
    Publication date: October 3, 2013
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Shinya Miyazaki, Hironori Shirakata
  • Publication number: 20120028130
    Abstract: A non-aqueous electrolyte secondary cell having high temperature storage characteristics and cycle characteristics is provided. This object is realized by adopting the following configuration. The non-aqueous electrolyte secondary cell includes a positive electrode having a positive electrode active material; a negative electrode having a negative electrode active material; and a non-aqueous electrolyte having a non-aqueous solvent and an electrolyte salt. And the positive electrode active material contains a compound represented by Lia(NibCocMnd)1?x?yWxZryO2 (0.9?a?1.2, 0.3?b?0.6, 0.1?c?0.7, 0?d?0.4, b+c+d=1, 0.001?x?0.05, 0.001?y?0.05); and the non-aqueous electrolyte contains at least one compound selected from the group consisting of cyclohexylbenzene, tert-butylbenzene and tert-amylbenzene in a total concentration of 0.1 to 5% by mass relative to the mass of the non-aqueous electrolyte.
    Type: Application
    Filed: July 29, 2011
    Publication date: February 2, 2012
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Shinya Miyazaki, Hironori Shirakata
  • Publication number: 20110177364
    Abstract: Provided is a nonaqueous electrolyte secondary battery using lithium-manganese composite oxide as positive electrode active material, having superior high-temperature charge storage characteristics and charge-discharge cycling characteristics and enhanced safety in the event of overcharging. A nonaqueous electrolyte secondary battery according to an aspect of the invention includes: a positive electrode plate provided with a positive electrode mixture containing positive electrode active material, a negative electrode plate, a nonaqueous electrolyte, and a pressure-sensitive safety mechanism that is actuated by rise in internal pressure. The positive electrode active material contains lithium-manganese composite oxide containing 10 to 61% by mass of the element manganese. The positive electrode mixture contains lithium carbonate or calcium carbonate, and lithium phosphate.
    Type: Application
    Filed: January 20, 2011
    Publication date: July 21, 2011
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Shinya Miyazaki, Hironori Shirakata
  • Publication number: 20100248022
    Abstract: The nonaqueous electrolyte secondary battery having high output characteristics and excellent safety when overcharging as well as excellent charge and discharge cycle characteristics according to an aspect of the invention includes a positive electrode having a positive electrode active material, a negative electrode having a negative electrode active material, a separator, and a nonaqueous electrolyte. The positive electrode active material includes lithium iron phosphate having an olivine crystal structure represented by General Formula LixFePO4 (where x is 0<x<1.3), the negative electrode active material includes a carbon material having an average operating potential of 0.3 V or less based on lithium in a range of 10 to 30% depth of discharge at the time of discharging at 6 mA/cm2, and the nonaqueous electrolyte includes an alkoxybenzene derivative within a range of 0.1 to 5.0% by mass.
    Type: Application
    Filed: March 11, 2010
    Publication date: September 30, 2010
    Applicant: SANYO ELECTRIC CO., LTD.
    Inventors: Hironori Shirakata, Yasunobu Iwami, Masato Iwanaga
  • Publication number: 20090068560
    Abstract: A non-aqueous electrolyte secondary battery has a negative electrode, a non-aqueous electrolyte, and a positive electrode containing a positive electrode active material composed of an olivine lithium-containing metal phosphate represented by the general formula LixMPO4, where M is at least one element selected from the group consisting of Co, Ni, Mn, and Fe, and 0<x<1.3. The positive electrode active material contains a LixMPO4 aggregate formed by granulating a LixMPO4 having an average particle size of 1 ?m or less in a volumetric particle size distribution by coating the LixMPO4 with a binding agent composed of a carbonaceous substance. The LixMPO4 aggregate has an average particle size of 3 ?m or less in the volumetric particle size distribution and a 90th percentile particle size (D90) of 7 ?m or greater, as measured at the 90th percentile point of the volumetric particle size distribution.
    Type: Application
    Filed: August 22, 2008
    Publication date: March 12, 2009
    Inventors: Koji Hasumi, Hiroyuki Akita, Hironori Shirakata, Yoshinori Kida, Toshikazu Yoshida, Kazunori Donoue, Takashi Yamamoto, Tetsuyuki Murata, Shigeki Matsuta
  • Publication number: 20080096098
    Abstract: A non-aqueous electrolyte secondary battery has a positive electrode (1), a negative electrode (2), and a non-aqueous electrolyte. The positive electrode has a positive electrode mixture layer containing a positive electrode active material, a binder agent, and a conductive agent. The positive electrode active material in the positive electrode mixture layer contains an olivine-type lithium-containing metal phosphate represented by the general formula LixMPO4, where M is at least one element selected from the group consisting of Co, Ni, Mn, and Fe, and x is 0<x<1.3. The conductive agent in the positive electrode mixture layer is composed of a mixture of carbon particles and carbon fiber.
    Type: Application
    Filed: October 19, 2007
    Publication date: April 24, 2008
    Inventors: Hironori Shirakata, Koji Hasumi, Hiroyuki Akita, Kazunori Donoue, Yoshinori Kida
  • Publication number: 20070248886
    Abstract: A non-aqueous electrolyte secondary battery includes a positive electrode (11), a negative electrode (12), and a non-aqueous electrolyte (14). The positive electrode contains a lithium-free metal oxide and a positive electrode active material composed of an olivine-type lithium-containing phosphate represented by the general formula LixMPO4, where M is at least one element selected from the group consisting of Co, Ni, Mn, and Fe, and 0<x<1.3.
    Type: Application
    Filed: March 30, 2007
    Publication date: October 25, 2007
    Inventors: Hironori Shirakata, Hideki Kitao, Yoshinori Kida
  • Publication number: 20060216605
    Abstract: In a non-aqueous electrolyte secondary battery employing an olivine-type lithium phosphate as a positive electrode active material, power regeneration performance is improved. The non-aqueous electrolyte secondary battery for use as a power source for regenerative charging includes: a positive electrode including a mixture layer containing a positive electrode active material, a binder agent, and a carbon material as a conductive agent; a negative electrode; and a non-aqueous electrolyte. The mixture layer contains, as the positive electrode active material, an olivine-type lithium phosphate represented by the formula LiMPO4, where M is at least one element selected from the group consisting of Co, Ni, Mn, and Fe, and the mixture layer further contains a metal oxide such as a lithium-containing transition metal oxide containing at least Ni or Mn.
    Type: Application
    Filed: March 20, 2006
    Publication date: September 28, 2006
    Inventors: Hironori Shirakata, Hideki Kitao, Hiroyuki Akita, Koji Hasumi, Yoshinori Kida, Toyoki Fujihara, Kazuhisa Takeda, Naoya Nakanishi, Toshiyuki Nohma