Patents by Inventor Yoshiyuki Muraoka

Yoshiyuki Muraoka 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: 11411274
    Abstract: An object of the present disclosure is to provide a high-endurance and long-life nonaqueous electrolyte secondary battery including a battery case having sealing performance unlikely to be degraded. A nonaqueous electrolyte secondary battery according to an aspect of the present disclosure includes a closed-end cylindrical outer can, a sealing body that closes an opening of the outer can, a resin gasket disposed between the outer can and the sealing body, a sealing member interposed between the outer can and the gasket, and a nonaqueous electrolyte. The sealing member has a multilayer structure including a first sealing member layer, the main constituent of which is one selected from butadiene rubber, urethane rubber, silicone rubber, chloroprene rubber, and isoprene rubber, and a second sealing member layer, the main constituent of which is one selected from ethylene propylene rubber, ethylene propylene diene rubber, and fluoro rubber.
    Type: Grant
    Filed: September 3, 2018
    Date of Patent: August 9, 2022
    Assignee: SANYO Electric Co., Ltd.
    Inventors: Yukihiro Oki, Yoshiyuki Muraoka, Shuichi Yamashita
  • Publication number: 20200185669
    Abstract: An object of the present disclosure is to provide a high-endurance and long-life nonaqueous electrolyte secondary battery including a battery case having sealing performance unlikely to be degraded. A nonaqueous electrolyte secondary battery according to an aspect of the present disclosure includes a closed-end cylindrical outer can, a sealing body that closes an opening of the outer can, a resin gasket disposed between the outer can and the sealing body, a sealing member interposed between the outer can and the gasket, and a nonaqueous electrolyte. The sealing member has a multilayer structure including a first sealing member layer, the main constituent of which is one selected from butadiene rubber, urethane rubber, silicone rubber, chloroprene rubber, and isoprene rubber, and a second sealing member layer, the main constituent of which is one selected from ethylene propylene rubber, ethylene propylene diene rubber, and fluoro rubber.
    Type: Application
    Filed: September 3, 2018
    Publication date: June 11, 2020
    Applicant: SANYO Electric Co., Ltd.
    Inventors: Yukihiro Oki, Yoshiyuki Muraoka, Shuichi Yamashita
  • Patent number: 10535851
    Abstract: A cylindrical lithium ion battery in which an electrode group formed by winding a positive electrode and a negative electrode is housed in a battery case is disclosed. A sealing plate seals an opening of the battery case. An insulating plate having a plurality of openings is provided on a side of the electrode group closer to the sealing plate. The plurality of openings include a first hole with a largest opening area, and a plurality of second holes with opening areas smaller than the opening area of the first hole. An opening ratio of the first hole is 12% or more and 40% or less; a sum of opening ratios of the second holes is 0.3% or more and 10% or less; and a total opening ratio of all the openings is 20% or more and 50% or less.
    Type: Grant
    Filed: June 20, 2018
    Date of Patent: January 14, 2020
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Tomohiko Yokoyama, Yoshiyuki Muraoka, Takahiro Fukuoka, Kyosuke Miyata
  • Patent number: 10340521
    Abstract: An object of the invention is to provide a nonaqueous electrolyte secondary battery having good cycle characteristics. The nonaqueous electrolyte secondary battery of the present invention includes a positive electrode containing a positive electrode active material, a negative electrode containing a negative electrode active material, a separator interposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte. The positive electrode active material is a layered lithium transition metal oxide, and the positive electrode active material has a crystallite size of 140 nm or less. The negative electrode active material contains at least carbon, and the nonaqueous electrolyte contains 2 to 30% by volume of fluoroethylene carbonate.
    Type: Grant
    Filed: February 13, 2015
    Date of Patent: July 2, 2019
    Assignee: SANYO Electric Co., Ltd.
    Inventors: Atsushi Ogata, Yoshiyuki Muraoka, Katsunori Yanagida, Masanobu Takeuchi, Fumiharu Niina
  • Publication number: 20180301677
    Abstract: A cylindrical lithium ion battery in which an electrode group formed by winding a positive electrode and a negative electrode is housed in a battery case is disclosed. A sealing plate seals an opening of the battery case. An insulating plate having a plurality of openings is provided on a side of the electrode group closer to the sealing plate. The plurality of openings include a first hole with a largest opening area, and a plurality of second holes with opening areas smaller than the opening area of the first hole. An opening ratio of the first hole is 12% or more and 40% or less; a sum of opening ratios of the second holes is 0.3% or more and 10% or less; and a total opening ratio of all the openings is 20% or more and 50% or less.
    Type: Application
    Filed: June 20, 2018
    Publication date: October 18, 2018
    Inventors: Tomohiko YOKOYAMA, Yoshiyuki MURAOKA, Takahiro FUKUOKA, Kyosuke MIYATA
  • Patent number: 10056606
    Abstract: It is an object to improve the initial charge-discharge efficiency of a nonaqueous electrolyte secondary battery that uses, as negative electrode active materials, a carbon material and a metal or metal oxide that forms an alloy with lithium. There is provided a nonaqueous electrolyte secondary battery including a positive electrode, a nonaqueous electrolyte, and a negative electrode which includes, as negative electrode active materials, a carbon material and a metal or metal oxide that forms an alloy with lithium and in which at least part of a surface of the carbon material is coated with a polymer material that does not react with lithium. The mass percentage of the polymer material that does not react with lithium relative to the carbon material is preferably 0.5 to 2 mass %.
    Type: Grant
    Filed: February 10, 2014
    Date of Patent: August 21, 2018
    Assignee: SANYO Electric Co., Ltd.
    Inventors: Yoshiyuki Muraoka, Kei Kobayashi, Tatsuki Hiraoka, Masahiro Shiraga
  • Patent number: 10026938
    Abstract: A cylindrical lithium ion battery in which an electrode group formed by winding a positive electrode and a negative electrode is housed in a battery case is disclosed. A sealing plate seals an opening of the battery case. An insulating plate having a plurality of openings is provided on a side of the electrode group closer to the sealing plate. The plurality of openings include a first hole with a largest opening area, and a plurality of second holes with opening areas smaller than the opening area of the first hole. An opening ratio of the first hole is 12% or more and 40% or less; a sum of opening ratios of the second holes is 0.3% or more and 10% or less; and a total opening ratio of all the openings is 20% or more and 50% or less.
    Type: Grant
    Filed: September 16, 2016
    Date of Patent: July 17, 2018
    Assignee: Panasonic Intellectual Property Management Co, Ltd.
    Inventors: Tomohiko Yokoyama, Yoshiyuki Muraoka, Takahiro Fukuoka, Kyosuke Miyata
  • Publication number: 20170346071
    Abstract: Nonaqueous electrolyte secondary batteries are provided which are resistant to a decrease in capacity associated with charge and discharge cycles and have excellent discharge rate characteristics. A nonaqueous electrolyte secondary battery according to an example embodiment includes a positive electrode including a lithium transition metal oxide, a negative electrode and a nonaqueous electrolyte. The lithium transition metal oxide has a content of voids within particles of 0.2 to 30% before first charging. The nonaqueous electrolyte includes a fluorinated cyclic carbonate and a fluorinated chain carboxylate ester.
    Type: Application
    Filed: August 16, 2017
    Publication date: November 30, 2017
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Atsushi Ogata, Katsunori Yanagida, Takanobu Chiga, Naoya Morisawa, Yoshiyuki Muraoka
  • Patent number: 9705159
    Abstract: A nonaqueous electrolyte secondary battery includes: a positive electrode 4 including a positive electrode current collector and a positive electrode mixture layer containing a positive electrode active material and a binder, the positive electrode mixture layer being provided on the positive electrode current collector; a negative electrode 5; a porous insulating layer 6 interposed between the positive electrode 4 and the negative electrode 5; and a nonaqueous electrolyte. The positive electrode 4 has a tensile extension percentage of equal to or higher than 3.0%. The positive electrode current collector is made of aluminum containing iron. In this manner, the tensile extension percentage of the positive electrode is increased without a decrease in capacity of the nonaqueous electrolyte secondary battery. Accordingly, even when the nonaqueous electrolyte secondary battery is destroyed by crush, occurrence of short-circuit in the nonaqueous electrolyte secondary battery can be suppressed.
    Type: Grant
    Filed: July 25, 2014
    Date of Patent: July 11, 2017
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Yoshiyuki Muraoka, Kozo Watanabe, Kaoru Inoue, Yukihiro Okada
  • Publication number: 20170062818
    Abstract: An object of the invention is to provide a nonaqueous electrolyte secondary battery having good cycle characteristics. The nonaqueous electrolyte secondary battery of the present invention includes a positive electrode containing a positive electrode active material, a negative electrode containing a negative electrode active material, a separator interposed between the positive electrode and the negative electrode, and a nonaqueous electrolyte. The positive electrode active material is a layered lithium transition metal oxide, and the positive electrode active material has a crystallite size of 140 nm or less. The negative electrode active material contains at least carbon, and the nonaqueous electrolyte contains 2 to 30% by volume of fluoroethylene carbonate.
    Type: Application
    Filed: February 13, 2015
    Publication date: March 2, 2017
    Applicant: SANYO Electric Co., Ltd.
    Inventors: Atsushi Ogata, Yoshiyuki Muraoka, Katsunori Yanagida, Masanobu Takeuchi, Fumiharu Niina
  • Patent number: 9559362
    Abstract: The nonaqueous electrolyte secondary battery of the invention includes: a wound-type electrode group including a long positive electrode, a long negative electrode, and a separator disposed between the positive electrode and the negative electrode; a nonaqueous electrolyte; and a prismatic battery case accommodating the electrode group and the nonaqueous electrolyte. A horizontal cross-section of the electrode group has a major axis and a minor axis. The positive electrode includes a positive electrode current collector and a positive electrode active material layer disposed thereon, and the negative electrode includes a negative electrode current collector and a negative electrode active material layer disposed thereon. A tensile strength of the positive electrode when an elongation percentage in a longitudinal direction of the positive electrode is 1% is not greater than 15 N/cm.
    Type: Grant
    Filed: March 31, 2009
    Date of Patent: January 31, 2017
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Yoshiyuki Muraoka, Yukihiro Okada
  • Publication number: 20170005306
    Abstract: A cylindrical lithium ion battery in which an electrode group formed by winding a positive electrode and a negative electrode is housed in a battery case is disclosed. A sealing plate seals an opening of the battery case. An insulating plate having a plurality of openings is provided on a side of the electrode group closer to the sealing plate. The plurality of openings include a first hole with a largest opening area, and a plurality of second holes with opening areas smaller than the opening area of the first hole. An opening ratio of the first hole is 12% or more and 40% or less; a sum of opening ratios of the second holes is 0.3% or more and 10% or less; and a total opening ratio of all the openings is 20% or more and 50% or less.
    Type: Application
    Filed: September 16, 2016
    Publication date: January 5, 2017
    Inventors: Tomohiko YOKOYAMA, Yoshiyuki MURAOKA, Takahiro FUKUOKA, Kyosuke MIYATA
  • Patent number: 9484599
    Abstract: Provided is a non-aqueous electrolyte secondary battery having a high capacity and an improved cycle life. The battery includes an electrode group and a non-aqueous electrolyte, and has a volume energy density of 650 Wh/L or more. The electrode group includes wound positive and negative electrodes with a separator interposed therebetween. The positive and negative electrodes each include a current collector and a material mixture layer adhering thereto. The positive and negative electrode material mixture layers each have a porosity Pp of 22% or less and porosity Pn of 25% or less. The ratio VE/VT of a volume VE of the electrolyte to a total VT of the pore volumes of the positive and negative electrode material mixture layers, and the separator is 1 to 1.5. The difference between contact angles CAp and CAn of the positive and negative electrodes with respect to the non-aqueous electrolyte is 23° or less.
    Type: Grant
    Filed: August 30, 2012
    Date of Patent: November 1, 2016
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Atsushi Mizawa, Yoshiyuki Muraoka
  • Patent number: 9472795
    Abstract: A cylindrical lithium ion battery in which an electrode group formed by winding a positive electrode and a negative electrode is housed in a battery case is disclosed. A sealing plate seals an opening of the battery case. An insulating plate having a plurality of openings is provided on a side of the electrode group closer to the sealing plate. The plurality of openings include a first hole with a largest opening area, and a plurality of second holes with opening areas smaller than the opening area of the first hole. An opening ratio of the first hole is 12% or more and 40% or less; a sum of opening ratios of the second holes is 0.3% or more and 10% or less; and a total opening ratio of all the openings is 20% or more and 50% or less.
    Type: Grant
    Filed: December 28, 2012
    Date of Patent: October 18, 2016
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Tomohiko Yokoyama, Yoshiyuki Muraoka, Takahiro Fukuoka, Kyosuke Miyata
  • Patent number: 9379376
    Abstract: A method for producing a positive electrode for non-aqueous electrolyte secondary battery of the present invention includes the steps of: (1) producing a positive electrode precursor by applying a positive electrode slurry including a positive electrode active material comprising a lithium-containing composite oxide including nickel, a binder, and a conductive agent on a positive electrode core material, the positive electrode active material including secondary particles having an average particle diameter of 8 ?m or more, and then drying the positive electrode slurry to form a positive electrode material mixture layer; and (2) rolling while heating the positive electrode precursor to produce a positive electrode in which 3.5 g or more of the positive electrode active material is included per 1 cm3 of the positive electrode material mixture layer, and the positive electrode active material includes secondary particles having an average particle diameter of 5 ?m or more.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: June 28, 2016
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Junichi Sugaya, Yoshiyuki Muraoka
  • Patent number: 9257717
    Abstract: In a wound electrode group, a positive electrode includes positive electrode active material layers formed on both surfaces of a band-like positive electrode current collector, and a negative electrode includes negative electrode active material layers on both surfaces of a band-like negative electrode current collector. Charge capacity of the negative electrode falls within a range of 83-99% of theoretical capacity of the negative electrode in a full charge state of a nonaqueous electrolyte secondary battery. An active material mass M1 per unit area of a negative electrode active material layer formed on an outer circumference of the negative electrode current collector, and an active material mass M2 per unit area of a negative electrode active material layer formed on an inner circumference satisfy a relational expression of M1/M2<(R1+t/2)/(R1?t/2), where the electrode group has an innermost diameter of R1, and the negative electrode has a thickness of t.
    Type: Grant
    Filed: April 3, 2012
    Date of Patent: February 9, 2016
    Assignee: PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO., LTD.
    Inventors: Yoshiyuki Muraoka, Masaya Ugaji, Takahiro Aoyama, Haruya Nakai
  • Publication number: 20150372306
    Abstract: It is an object to improve the initial charge-discharge efficiency of a nonaqueous electrolyte secondary battery that uses, as negative electrode active materials, a carbon material and a metal or metal oxide that forms an alloy with lithium. There is provided a nonaqueous electrolyte secondary battery including a positive electrode, a nonaqueous electrolyte, and a negative electrode which includes, as negative electrode active materials, a carbon material and a metal or metal oxide that forms an alloy with lithium and in which at least part of a surface of the carbon material is coated with a polymer material that does not react with lithium. The mass percentage of the polymer material that does not react with lithium relative to the carbon material is preferably 0.5 to 2 mass %.
    Type: Application
    Filed: February 10, 2014
    Publication date: December 24, 2015
    Applicant: SANYO Electric Co., Ltd.
    Inventors: Yoshiyuki Muraoka, Kei Kobayashi, Tatsuki Hiraoka, Masahiro Shiraga
  • Patent number: 8999585
    Abstract: A nonaqueous electrolyte secondary battery includes a positive electrode, a negative electrode, a porous insulating layer, and nonaqueous electrolyte. The porous insulating layer is interposed between the positive electrode and the negative electrode. The nonaqueous electrolyte is contained at least in the porous insulating layer. The mixture layer of the positive electrode and the porous insulating layer each include a structure retainer.
    Type: Grant
    Filed: July 18, 2008
    Date of Patent: April 7, 2015
    Assignee: Panasonic Intellectual Property Management Co., Ltd.
    Inventors: Yukihiro Okada, Yoshiyuki Muraoka
  • Publication number: 20150010793
    Abstract: A cylindrical lithium ion battery in which an electrode group formed by winding a positive electrode and a negative electrode is housed in a battery case is disclosed. A sealing plate seals an opening of the battery case. An insulating plate having a plurality of openings is provided on a side of the electrode group closer to the sealing plate. The plurality of openings include a first hole with a largest opening area, and a plurality of second holes with opening areas smaller than the opening area of the first hole. An opening ratio of the first hole is 12% or more and 40% or less; a sum of opening ratios of the second holes is 0.3% or more and 10% or less; and a total opening ratio of all the openings is 20% or more and 50% or less.
    Type: Application
    Filed: December 28, 2012
    Publication date: January 8, 2015
    Applicant: PANASONIC CORPORATION
    Inventors: Tomohiko Yokoyama, Yoshiyuki Muraoka, Takahiro Fukuoka, Kyosuke Miyata
  • Publication number: 20140331485
    Abstract: A nonaqueous electrolyte secondary battery includes: a positive electrode 4 including a positive electrode current collector and a positive electrode mixture layer containing a positive electrode active material and a binder, the positive electrode mixture layer being provided on the positive electrode current collector; a negative electrode 5; a porous insulating layer 6 interposed between the positive electrode 4 and the negative electrode 5; and a nonaqueous electrolyte. The positive electrode 4 has a tensile extension percentage of equal to or higher than 3.0%. The positive electrode current collector is made of aluminium containing iron. In this manner, the tensile extension percentage of the positive electrode is increased without a decrease in capacity of the nonaqueous electrolyte secondary battery. Accordingly, even when the nonaqueous electrolyte secondary battery is destroyed by crush, occurrence of short-circuit in the nonaqueous electrolyte secondary battery can be suppressed.
    Type: Application
    Filed: July 25, 2014
    Publication date: November 13, 2014
    Inventors: Yoshiyuki MURAOKA, Kozo WATANABE, Kaoru INOUE, Yukihiro OKADA