Patents by Inventor Akira Tsujiko

Akira Tsujiko 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: 20230369583
    Abstract: A positive electrode active material 1 disclosed herein includes a Ni content lithium complex oxide containing 70 mol % or more of nickel relative to the total of metal elements other than lithium, and a boron element. The Ni content lithium complex oxide is in a form of a secondary particle in which primary particles are aggregated and has a porosity of 2% or more and 10% or less, and inside the secondary particle, a larger space than an average cross-sectional area of the primary particles does not exist. The boron element is contained by 0.5 to 3 mol % when the total of metal elements of the Ni content lithium complex oxide is 100 mol %.
    Type: Application
    Filed: May 8, 2023
    Publication date: November 16, 2023
    Applicant: PRIME PLANET ENERGY & SOLUTIONS, INC.
    Inventors: Shinya SUZUKI, Akira TSUJIKO
  • Publication number: 20230369574
    Abstract: A positive electrode of a nonaqueous electrolyte secondary battery disclosed herein includes a positive electrode active material layer with a multilayer structure including a positive electrode lower layer and a positive electrode upper layer. The positive electrode lower layer includes a first positive electrode active material including a first Ni content lithium complex oxide. The positive electrode upper layer includes a second positive electrode active material including a second Ni content lithium complex oxide, and does not include a larger space than an average cross-sectional area of the primary particles inside the secondary particle, and a covering element. The ratio of the covering element is 0.5 to 3 mol % when the total of metal elements of the second Ni content lithium complex oxide is 100 mol %.
    Type: Application
    Filed: May 8, 2023
    Publication date: November 16, 2023
    Inventors: Shinya SUZUKI, Akira TSUJIKO
  • Publication number: 20230317928
    Abstract: The present disclosure relates to a positive electrode comprising a positive electrode active material layer and a positive electrode base material, wherein the positive electrode active material layer includes a positive electrode active material, the positive electrode active material includes a layered metal oxide, the ratio of nickel to the total amount of nickel and a transition metal in the layered metal oxide is 70% or more, and the positive electrode active material present near a surface of the positive electrode active material layer closer to the positive electrode base material has a crystallite diameter that is 200 Å to 500 Å greater than the positive electrode active material present near a surface of the positive electrode active material layer opposite to the positive electrode base material. According to the present disclosure, a positive electrode and a battery each of which is excellent in both endurance and efficiency are provided.
    Type: Application
    Filed: March 7, 2023
    Publication date: October 5, 2023
    Inventors: Kouhei MASAI, Ryo HANAZAKI, Akira TSUJIKO
  • Patent number: 11646456
    Abstract: A battery system includes a battery that is a lithium ion battery including an electrode assembly containing a positive electrode active material. An ECU calculates a deterioration index value ?D corresponding a degree of progress of high rate deterioration, and when the deterioration index value ?D exceeds a threshold value, controls a power converter or a PCU to cause a voltage of the battery to fall within a voltage range including a specific voltage. The specific voltage is a peak voltage on a dQ/dV voltage characteristic curve, the peak voltage being derived from structural change of the positive electrode active material. The dQ/dV voltage characteristic curve is a curve indicating a relationship between dQ/dV that is a ratio of a change dQ of a stored electricity amount to a change dV of the voltage of the battery, and the voltage of the battery.
    Type: Grant
    Filed: September 9, 2020
    Date of Patent: May 9, 2023
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventor: Akira Tsujiko
  • Publication number: 20230017772
    Abstract: Manufacturing a lithium-ion battery includes assembling the lithium-ion battery; and performing an initial charging on the lithium-ion battery. The lithium-ion battery includes a positive electrode, a negative electrode, and an electrolyte; the negative electrode contains a negative electrode active material containing a precursor of a silicon material, the precursor having a composition represented by SiOx where a relationship of 0<x<2 is satisfied. The initial charging includes a first step where the charging is performed to an intermediate voltage at a first current rate, and a second step where the charging is performed from the intermediate voltage to a maximum voltage at a second current rate. The first current rate is lower than 0.5 C; the second current rate is higher than the first current rate; and the intermediate voltage is 3.75 V or higher.
    Type: Application
    Filed: September 9, 2022
    Publication date: January 19, 2023
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Akira TSUJIKO, Hiroki IGUCHI
  • Publication number: 20220399535
    Abstract: The negative electrode disclosed herein includes: a negative electrode current collector; and a negative electrode active material layer formed on the surface of the negative electrode current collector. The negative electrode active material layer contains silicon oxide containing at least one alkali earth metal. The negative electrode active material layer includes at least a first layer and a second layer. The first layer is disposed between the second layer and the negative electrode current collector. The second layer contains 2 mass % or less of the silicon oxide containing the alkali earth metal, relative to 100 mass % of the negative electrode active material in the second layer. The amount of the alkali earth metal in the first layer calculated based on energy dispersive X-ray spectroscopy using a scanning electron microscope image is higher than the amount of the alkali earth metal in the second layer.
    Type: Application
    Filed: June 13, 2022
    Publication date: December 15, 2022
    Inventors: Yuki Morikawa, Akira Tsujiko
  • Publication number: 20220393148
    Abstract: The negative electrode disclosed herein includes: a negative electrode current collector; and a negative electrode active material layer formed on the surface of the negative electrode current collector. The negative electrode active material layer contains silicon oxide containing at least one alkali earth metal. The negative electrode active material layer includes at least a first layer and a second layer. The first layer is disposed between the second layer and the negative electrode current collector. The amount of the alkali earth metal in the second layer calculated based on energy dispersive X-ray spectroscopy using a scanning electron microscope image is higher than the amount of the alkali earth metal in the first layer.
    Type: Application
    Filed: June 7, 2022
    Publication date: December 8, 2022
    Inventors: Yuki MORIKAWA, Akira TSUJIKO
  • Publication number: 20220328822
    Abstract: The positive electrode is provided with a positive electrode current collector and a positive electrode active material layer that is supported on the positive electrode current collector. The positive electrode active material layer contains a positive electrode active material and a surfactant. The positive electrode active material contains a lithium composite oxide that has a nickel content, with respect to the metal atoms other than lithium, of at least 70 mol %. The positive electrode active material layer has a multilayer structure that includes at least two layers that have different mass percentages of the surfactant with respect to the total of the positive electrode active material and the surfactant. The mass percentage of the surfactant in a layer that has a larger mass percentage of surfactant, of the layers present in the multilayer structure is not less than 1.0 mass % and not more than 10 mass %.
    Type: Application
    Filed: March 30, 2022
    Publication date: October 13, 2022
    Inventors: Shinya SUZUKI, Akira TSUJIKO
  • Publication number: 20220328810
    Abstract: A positive electrode includes a current collector, and an active material layer provided on the current collector. The active material layer has a first layer located on the current collector side and a second layer located on a surface layer side of the active material layer. A proportion of a thickness of the second layer to a total thickness of the first and second layers is from 0.20 to 0.80. When each specific capacity of a potential flat portion near 4.2 V in a charging voltage curve is measured for the first and second layers, the above specific capacity of the second layer is larger than that of the first layer. The above specific capacity of the second layer is greater than 17 mAh/g and at most 30 mAh/g. The above specific capacity of the first layer is from 2 mAh/g to 17 mAh/g.
    Type: Application
    Filed: April 8, 2022
    Publication date: October 13, 2022
    Inventors: Keiichi TAKAHASHI, Ryo HANAZAKI, Akira TSUJIKO
  • Publication number: 20220271295
    Abstract: The positive electrode active material layer is placed on a surface of the positive electrode substrate. The positive electrode active material layer includes a first layer and a second layer. The first layer is interposed between the positive electrode substrate and the second layer. The positive electrode active material layer includes a positive electrode active material, carbon black, and fibrous carbon. A mass fraction of the carbon black in the first layer is higher than a mass fraction of the carbon black in the second layer. A mass fraction of the fibrous carbon in the second layer is higher than a mass fraction of the fibrous carbon in the first layer.
    Type: Application
    Filed: February 24, 2022
    Publication date: August 25, 2022
    Inventors: Shinya SUZUKI, Akira TSUJIKO
  • Patent number: 11424437
    Abstract: A negative electrode for a non-aqueous electrolyte secondary battery is provided. The negative electrode includes at least a negative electrode active material. The negative electrode active material includes a first type of silicon oxide particles and a second type of silicon oxide particles. The first type of silicon oxide particles has not been pre-doped with lithium. The second type of silicon oxide particles has been pre-doped with lithium. The first type of silicon oxide particles has a first average particle size. The second type of silicon oxide particles has a second average particle size. The ratio of the second average particle size to the first average particle size is not lower than 1.5 and not higher than 11.2.
    Type: Grant
    Filed: July 9, 2019
    Date of Patent: August 23, 2022
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Ryosuke Ohsawa, Akira Tsujiko, Kaoru Inoue
  • Patent number: 11296314
    Abstract: A negative electrode material contains composite particles. Each of the composite particles contains a negative electrode active material particle and a film. The negative electrode active material particle contains a silicon oxide phase and a lithium silicate phase. The film covers a surface of the negative electrode active material particle. The film contains an anion-exchange resin. To an ion-exchange group of the anion-exchange resin, a fluoride ion is bound. The content of the anion-exchange resin in the negative electrode material is not higher than 33 mass %.
    Type: Grant
    Filed: February 28, 2019
    Date of Patent: April 5, 2022
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Ryosuke Ohsawa, Akira Tsujiko, Kaoru Inoue
  • Patent number: 11145848
    Abstract: A method of producing a secondary battery disclosed here includes forming a positive electrode active material layer containing a lithium- and manganese-containing composite oxide on a positive electrode current collector to produce a positive electrode; measuring a peel strength between the positive electrode active material layer and the positive electrode current collector; producing a secondary battery assembly including the positive electrode, a negative electrode, and a nonaqueous electrolyte using the positive electrode; and initially charging the secondary battery assembly. When the secondary battery assembly is initially charged, a restraining pressure is determined based on the measured peel strength, and in a predetermined peel strength range, a higher restraining pressure is set for a secondary battery assembly including a positive electrode having a low peel strength than for a secondary battery assembly including a positive electrode having a large peel strength.
    Type: Grant
    Filed: January 10, 2020
    Date of Patent: October 12, 2021
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Akira Tsujiko, Ippei Goto
  • Patent number: 11139464
    Abstract: A first silicon oxide material and a second silicon oxide material are prepared. A dispersion is prepared by dispersing the first silicon oxide material in an aqueous carboxymethylcellulose solution. A negative electrode composite material slurry is prepared by dispersing the second silicon oxide material and a binder in the dispersion. A negative electrode is produced by applying the negative electrode composite material slurry to a surface of a negative electrode current collector and then performing drying. The binder includes no carboxymethylcellulose. The first silicon oxide material has not been pre-doped with lithium. The second silicon oxide material has been pre-doped with lithium.
    Type: Grant
    Filed: June 12, 2019
    Date of Patent: October 5, 2021
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Ryosuke Ohsawa, Akira Tsujiko, Kaoru Inoue
  • Publication number: 20210296638
    Abstract: Disclosed is a non-aqueous electrolyte secondary battery positive electrode that includes a positive electrode core and a positive electrode mixture layer disposed on the positive electrode core. The positive electrode mixture layer contains a positive electrode active material and carbon nanotubes. The positive electrode active material contains a lithium transition metal composite oxide (I) that either comprises secondary particles that are aggregates of primary particles having an average particle size of 1 ?m or greater, or is substantially composed of single particles, the lithium transition metal composite oxide (I) having a volume-based median diameter of 0.6 ?m to 6 ?m, and a lithium transition metal composite oxide (II) that comprises secondary particles that are aggregates of primary particles having an average particle size of less than 1 ?m, the lithium transition metal composite oxide (II) having a volume-based median diameter of 3 ?m to 25 ?m.
    Type: Application
    Filed: March 11, 2021
    Publication date: September 23, 2021
    Applicants: Panasonic Corporation, TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Kohei Kintsu, Takashi Ko, Natsumi Goto, Keiichi Takahashi, Fumiharu Niina, Sho Tsuruta, Ryo Hanazaki, Akira Tsujiko
  • Publication number: 20210203013
    Abstract: A battery system includes a battery that is a lithium ion battery including an electrode assembly containing a positive electrode active material. An ECU calculates a deterioration index value ED corresponding a degree of progress of high rate deterioration, and when the deterioration index value ED exceeds a threshold value, controls a power converter or a PCU to cause a voltage of the battery to fall within a voltage range including a specific voltage. The specific voltage is a peak voltage on a dQ/dV voltage characteristic curve, the peak voltage being derived from structural change of the positive electrode active material. The dQ/dV voltage characteristic curve is a curve indicating a relationship between dQ/dV that is a ratio of a change dQ of a stored electricity amount to a change dV of the voltage of the battery, and the voltage of the battery.
    Type: Application
    Filed: September 9, 2020
    Publication date: July 1, 2021
    Inventor: Akira TSUJIKO
  • Publication number: 20210202937
    Abstract: The lithium-ion battery includes a positive electrode, a negative electrode, and an electrolyte. The negative electrode contains a negative electrode active material. The negative electrode active material contains a silicon material. The silicon material contains a silicon alloy phase and a silicate phase. The silicon alloy phase has a three-dimensional network structure. The silicate phase is arranged in a mesh of the three-dimensional network structure. The three-dimensional network structure has an average mesh size of 2.8 nm to 3.5 nm.
    Type: Application
    Filed: December 15, 2020
    Publication date: July 1, 2021
    Applicant: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Akira TSUJIKO, Hiroki IGUCHI
  • Patent number: 10971726
    Abstract: The positive electrode includes a positive electrode composite layer. The negative electrode includes a negative electrode composite material layer. A whole of the positive electrode composite layer and a portion of the negative electrode composite material layer face each other with the separator being interposed therebetween. The negative electrode composite material layer includes a first region and a second region. The first region is a region that does not face the positive electrode composite layer and that extends from a position facing one end portion of the positive electrode composite layer to a point separated from the position by more than or equal to 0.1 mm and less than or equal to 10 mm. The second region is a region other than the first region. The first region includes silicon oxide doped with lithium. The second region includes silicon oxide.
    Type: Grant
    Filed: March 6, 2019
    Date of Patent: April 6, 2021
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Ryosuke Ohsawa, Akira Tsujiko, Kaoru Inoue
  • Patent number: 10892522
    Abstract: A nonaqueous electrolytic solution is a nonaqueous electrolytic solution for a lithium secondary battery, the lithium secondary battery including a positive electrode that includes a positive electrode active material, and a negative electrode that includes a negative electrode active material which is a carbonaceous material storing and releasing a lithium ion. The nonaqueous electrolytic solution includes: one or more anions selected from an oxalato borate anion and an oxalato phosphate anion; and one or more arylamine compounds. The nonaqueous electrolytic solution is present between the positive electrode and the negative electrode and conducts a lithium ion.
    Type: Grant
    Filed: December 18, 2017
    Date of Patent: January 12, 2021
    Assignee: TOYOTA JIDOSHA KABUSHIKI KAISHA
    Inventors: Mamoru Mizutani, Akira Kohyama, Akira Tsujiko
  • Patent number: 10886569
    Abstract: A non-aqueous electrolyte secondary battery includes a negative electrode, a positive electrode, and an electrolyte solution. The electrolyte solution contains at least one selected from the group consisting of ethylene carbonate, fluoroethylene carbonate, and vinylene carbonate. The negative electrode includes a negative electrode mixture layer. The negative electrode mixture layer contains a silicon-containing particle and a graphite particle. In a Log-differential pore volume distribution of the negative electrode mixture layer, the ratio of a Log-differential pore volume at a pore diameter of 2 ?m to a Log-differential pore volume at a pore diameter of 0.2 ?m is within a range of 10.5 to 33.1.
    Type: Grant
    Filed: September 25, 2018
    Date of Patent: January 5, 2021
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Ryosuke Ohsawa, Akira Tsujiko, Kaoru Inoue