Patents by Inventor Masato KURATSU

Masato KURATSU 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: 11456486
    Abstract: A nonaqueous electrolyte secondary battery which is provided with a positive electrode, a negative electrode and a nonaqueous electrolyte. The positive electrode contains: a positive electrode active material and a compound having a cobalt content of 30% by weight or more. The weight A of the compound and the total weight B of the positive electrode active material satisfy 0.01?A/(A+B)?0.15. The negative electrode contains a negative electrode active material. The nonaqueous electrolyte contains propylene carbonate and diethyl carbonate as nonaqueous solvents; the total amount of the propylene carbonate and the diethyl carbonate is 70% by volume or more relative to 100% by volume of the nonaqueous solvents; and the volume ratio of the propylene carbonate to the diethyl carbonate is within the range of from 1:1 to 1:19.
    Type: Grant
    Filed: October 25, 2019
    Date of Patent: September 27, 2022
    Assignee: KANEKA CORPORATION
    Inventor: Masato Kuratsu
  • Publication number: 20210344016
    Abstract: [Problem] Repeated charge and discharge of a nonaqueous electrolyte secondary battery result in gas generation and thus a reduction in the battery capacity. [Solving Means] The problem can be solved by providing a negative electrode for nonaqueous electrolyte secondary batteries including a negative electrode active material having an average operating potential of 0.5 V (vs. Li/Li+) or more and less than 2.0 V (vs. Li/Li+) during desorption and insertion of lithium ions, a conductive aid that is carbon nanotubes having a diameter of 100 nm or less, and a binder that is macromolecules having acidic functional groups.
    Type: Application
    Filed: July 8, 2021
    Publication date: November 4, 2021
    Applicant: KANEKA CORPORATION
    Inventor: Masato Kuratsu
  • Patent number: 11108079
    Abstract: A lithium-ion secondary battery includes: a laminate including a positive electrode, a negative electrode, and a separator; a nonaqueous electrolyte solution; terminals; and an inclusion body. The negative electrode includes a negative electrode active material including a titanium-containing oxide, and at least one negative electrode additive selected from a carbon material, a silicon-based material, a tin-based material, and a bismuth-based material. A relation between a weight (Ma) of the negative electrode additive and a weight (Mt) of the negative electrode active material is 1.0<Mt/Ma<30.0. An area (Sp) of a positive electrode active material layer of the positive electrode is smaller than an area (Sn) of a negative electrode active material layer of the negative electrode. A positive electrode capacity (Qp) is smaller than a negative electrode capacity (Qn).
    Type: Grant
    Filed: June 6, 2017
    Date of Patent: August 31, 2021
    Assignee: KANEKA CORPORATION
    Inventors: Masato Kuratsu, Yukimasa Niwa
  • Patent number: 10680235
    Abstract: A method for producing a positive electrode containing a positive electrode active material and/or a negative electrode containing a negative electrode active material. The method includes a process for producing an electrode slurry including: a first process in which a positive or negative electrode active material, a conductive additive, and a nonaqueous solvent are mixed to obtain a slurry; and a second process in which the slurry is diluted or concentrated and then mixed to obtain the electrode slurry. In the first process, the mixing is performed such that the obtained slurry has a water content of 1000 ppm or less and a viscosity of 500 cP or more and 8000 cP or less, and, in the second process, the mixing is performed such that a water content of the obtained electrode slurry is maintained at the water content of the slurry after the first process is completed.
    Type: Grant
    Filed: April 17, 2017
    Date of Patent: June 9, 2020
    Assignee: KANEKA CORPORATION
    Inventors: Fujika Ogaki, Masato Kuratsu, Ayumi Takaoka
  • Patent number: 10651468
    Abstract: The present invention provides a nonaqueous electrolyte secondary battery characterized by a significantly smaller amount of gas formation and excellent cycle stability exhibited during cycle testing even when a titanium compound is used for a negative electrode. A nonaqueous electrolyte secondary battery is structured to have a casing, encapsulating a positive electrode, nonaqueous electrolyte, and a negative electrode facing the positive electrode across a separator. The negative electrode contains a titanium compound as a negative-electrode active material, the separator is electrically insulative, the positive electrode contains a spinel-type lithium manganese oxide and a layered rock salt structure compound as positive-electrode active materials, the spinel-type lithium manganese oxide is set to have a number average particle size of 10 ?m to 20 ?m, and a specific surface area of 0.05 m2/g to 0.
    Type: Grant
    Filed: February 5, 2016
    Date of Patent: May 12, 2020
    Assignee: KANEKA CORPORATION
    Inventors: Ayumi Takaoka, Masato Kuratsu
  • Publication number: 20200067036
    Abstract: A battery pack includes a plurality of laminate batteries. Each of the laminate batteries contains a layered body, an outer packaging that is formed from a laminate film enclosing the layered body, a pair of electrode terminals. The outer packaging has a battery part and a bag part that is a space of which a volume is changeable, and communicates to the battery part through a single communication part, the bag part is disposed close to a second edge, which is opposite to a first edge, and the battery part is disposed close to the first edge. The laminate batteries are all arranged in a manner to have the second edges of the outer packagings on an upper side of the battery pack in a vertical direction, which is parallel to the gravity, and to have the first edge on a lower side of the battery pack in the vertical direction such that all the bag parts are disposed above the battery parts in the vertical direction.
    Type: Application
    Filed: October 29, 2019
    Publication date: February 27, 2020
    Inventors: Yuuki SAWADA, Yukimasa NIWA, Mitsuyasu IMAZAKI, Takashi KIKUCHI, Masato KURATSU
  • Publication number: 20200058961
    Abstract: A nonaqueous electrolyte secondary battery which is provided with a positive electrode, a negative electrode and a nonaqueous electrolyte. The positive electrode contains: a positive electrode active material and a compound having a cobalt content of 30% by weight or more. The weight A of the compound and the total weight B of the positive electrode active material satisfy 0.01?A/(A+B)?0.15. The negative electrode contains a negative electrode active material. The nonaqueous electrolyte contains propylene carbonate and diethyl carbonate as nonaqueous solvents; the total amount of the propylene carbonate and the diethyl carbonate is 70% by volume or more relative to 100% by volume of the nonaqueous solvents; and the volume ratio of the propylene carbonate to the diethyl carbonate is within the range of from 1:1 to 1:19.
    Type: Application
    Filed: October 25, 2019
    Publication date: February 20, 2020
    Applicant: KANEKA CORPORATION
    Inventor: Masato KURATSU
  • Publication number: 20190140259
    Abstract: A method for producing a positive electrode containing a positive electrode active material and/or a negative electrode containing a negative electrode active material. The method includes a process for producing an electrode slurry including: a first process in which a positive or negative electrode active material, a conductive additive, and a nonaqueous solvent are mixed to obtain a slurry; and a second process in which the slurry is diluted or concentrated and then mixed to obtain the electrode slurry. In the first process, the mixing is performed such that the obtained slurry has a water content of 1000 ppm or less and a viscosity of 500 cP or more and 8000 cP or less, and, in the second process, the mixing is performed such that a water content of the obtained electrode slurry is maintained at the water content of the slurry after the first process is completed.
    Type: Application
    Filed: April 17, 2017
    Publication date: May 9, 2019
    Applicant: KANEKA CORPORATION
    Inventors: Fujika OGAKI, Masato KURATSU, Ayumi TAKAOKA
  • Publication number: 20190115621
    Abstract: The present invention is intended to provide a lithium-ion secondary battery and an assembled battery that have good cycle characteristics and safety while using a negative electrode in which an additive such as a carbon-based material is used in combination with a titanium-containing oxide. In the present invention, a lithium-ion secondary battery includes: a laminate including a positive electrode, a negative electrode, and a separator; a nonaqueous electrolyte solution; terminals; and an inclusion body. The negative electrode includes: a negative electrode active material including a titanium-containing oxide; and at least one negative electrode additive selected from a carbon material, a silicon-based material, a tin-based material, and a bismuth-based material. A relation between a weight (Ma) of the negative electrode additive and a weight (Mt) of the negative electrode active material is 1.0<Mt/Ma<30.0.
    Type: Application
    Filed: June 6, 2017
    Publication date: April 18, 2019
    Applicant: KANEKA CORPORATION
    Inventors: Masato KURATSU, Yukimasa NIWA
  • Publication number: 20180034053
    Abstract: The present invention provides a nonaqueous electrolyte secondary battery characterized by a significantly smaller amount of gas formation and excellent cycle stability exhibited during cycle testing even when a titanium compound is used for a negative electrode. A nonaqueous electrolyte secondary battery is structured to have a casing, encapsulating a positive electrode, nonaqueous electrolyte, and a negative electrode facing the positive electrode across a separator. The negative electrode contains a titanium compound as a negative-electrode active material, the separator is electrically insulative, the positive electrode contains a spinel-type lithium manganese oxide and a layered rock salt structure compound as positive-electrode active materials, the spinel-type lithium manganese oxide is set to have a number average particle size of 10 ?m to 20 ?m, and a specific surface area of 0.05 m2/g to 0.
    Type: Application
    Filed: February 5, 2016
    Publication date: February 1, 2018
    Applicant: KANEKA CORPORATION
    Inventors: Ayumi TAKAOKA, Masato KURATSU
  • Publication number: 20170222197
    Abstract: A battery pack containing a plurality of plate-shaped laminate batteries arranged in a direction vertical to a plate-shaped surface of one of the laminate batteries. The laminate battery contains: a layered body which includes a negative electrode, a separator, and a positive electrode, and is disposed parallel to the plate-shaped surface of the laminate battery; an outer packaging including a laminate film enclosing the layered body; and an electrode terminal which is electrically connected to the layered body and extends from a one side part of the outer packaging. The outer packaging has, in an inside thereof, a battery part having a space in which the layered body exists and a bag part which has a space a volume of which is changeable, communicates to the battery part through a communication part, and is disposed on an other side part opposite to the one side part.
    Type: Application
    Filed: July 13, 2015
    Publication date: August 3, 2017
    Applicant: KANEKA CORPORATION
    Inventors: Yuuki SAWADA, Yukimasa NIWA, Mitsuyasu IMAZAKI, Takashi KIKUCHI, Masato KURATSU