Patents by Inventor Tomofumi YOKOYAMA

Tomofumi YOKOYAMA 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: 10411298
    Abstract: A polyelectrolyte composition is represented by the following formula (1). In the formula (1), R1 is hydrogen or CH3, R2 is any of C2H4, CH(CH3)CH2, and (CH2)3, m and n are each a copolymerization ratio of a structural unit in parentheses, and when m and n are set as follows: m+n=10, m and n satisfy the following formulae: 1?m?5 and 5?n?9, and p is 2 or more and 8 or less.
    Type: Grant
    Filed: November 6, 2017
    Date of Patent: September 10, 2019
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Hitoshi Yamamoto, Tomofumi Yokoyama
  • Publication number: 20190260072
    Abstract: An electrolyte according to the invention includes a first electrolyte portion, in which one or more types of elements among the elements constituting a crystalline lithium composite metal oxide represented by the compositional formula (1) are substituted with a first metal element having a crystal radius of 78 pm or more, and an amorphous second electrolyte portion, which contains Li and one or more types of second metal elements contained in the first electrolyte portion other than Li. Li7(La3?xNdx)Zr2O12??(1) In the formula, x satisfies the following formula: 0.0<x?0.6.
    Type: Application
    Filed: February 15, 2019
    Publication date: August 22, 2019
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hitoshi YAMAMOTO, Tomofumi YOKOYAMA
  • Publication number: 20190260068
    Abstract: An electrolyte according to the invention includes a crystalline first electrolyte portion which contains a lithium composite metal oxide represented by the compositional formula (1). (Li7?3xGax)(La3-yNdy)Zr2O12??(1) In the formula, x and y satisfy the following formulae: 0.1?x?1.0 and 0.01?y?0.2.
    Type: Application
    Filed: February 15, 2019
    Publication date: August 22, 2019
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hitoshi YAMAMOTO, Tomofumi YOKOYAMA
  • Patent number: 10340509
    Abstract: An electrode assembly 10 includes an assembly 4 including an active material compact (active material section) 2 including an active material constituted of a transition metal oxide, a solid electrolyte layer (solid electrolyte section) 3 including a solid electrolyte having an ion-conducting property, and a multiple oxide layer (multiple oxide section) 5 including at least one of a metal multiple oxide represented by General Formula (II) below and a derivative thereof and a collector 1 provided so as to join the active material compact 2 on one surface (first surface) 41 of the assembly. Ln2Li0.5M0.5O4??(II) In the formula, Ln represents a lanthanoid element, and M represents a transition metal.
    Type: Grant
    Filed: March 21, 2016
    Date of Patent: July 2, 2019
    Assignee: SEIKO EPSON CORPORATION
    Inventor: Tomofumi Yokoyama
  • Patent number: 10340549
    Abstract: A electrolyte is an electrolyte represented by the following formula (1): (Li7?3x+yGax)(La3?yCay)Zr2O12??(1) wherein 0.1?x?1, and 0.01?y?0.5.
    Type: Grant
    Filed: August 8, 2017
    Date of Patent: July 2, 2019
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Hitoshi Yamamoto, Tomofumi Yokoyama
  • Publication number: 20190198918
    Abstract: An electrolyte precursor solution includes a metallic compound containing elements constituting an electrolyte, a solvent capable of dissolving the metallic compound, and an anionic surfactant having a sulfate group (SO42?) bonded to a hydrophobic group R. By reacting such an electrolyte precursor solution with active material particles containing lithium, lithium sulfate derived from the anionic surfactant is interposed at the interface between the surface of the active material particle and the electrolyte so as to enhance the dissociation of lithium ions at the interface, and thus, an excellent ion conductivity can be realized.
    Type: Application
    Filed: December 21, 2018
    Publication date: June 27, 2019
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hitoshi YAMAMOTO, Tomofumi YOKOYAMA
  • Publication number: 20190131615
    Abstract: A lithium battery as a secondary battery has a battery cell including a first current collector which has a first face and a second face, a positive electrode active material particle which pierces the first current collector and is exposed from the first face and the second face, an electrolyte layer which covers the positive electrode active material particle exposed from the first face and the second face of the first current collector, a negative electrode as an electrode which is in contact with the electrolyte layer, and a second current collector which is in contact with the negative electrode. The battery cell is hermetically enclosed in a package in a state where one end portion which is a portion of the first current collector is exposed.
    Type: Application
    Filed: October 29, 2018
    Publication date: May 2, 2019
    Applicant: SEIKO EPSON CORPORATION
    Inventor: Tomofumi YOKOYAMA
  • Publication number: 20190097266
    Abstract: A solid electrolyte which reduces grain boundary resistance and exhibits a high total ion conductivity is provided. The solid electrolyte includes a first area which has a cubic garnet type crystalline and a second area which is amorphous, around the first area, in which each of the first area and the second area contains a composite oxide represented by formula (1) or (2) as a forming material, and an abundance ratio of metal atoms each having an ionic radius of 78 pm or more gradually increases from the first area to the second area. Li7+xLa3?xZr2AxO12??(1) [In formula (1), A is at least one selected from the group consisting of Mg, Ca, Sr, and Ba. In addition, x is 0.1 or more and 0.6 or less.] Li7La3?xZr2BxO12??(2) [In formula (2), B is at least one selected from the group consisting of Sc and Y. In addition, x is 0.1 or more and 0.6 or less.
    Type: Application
    Filed: March 3, 2017
    Publication date: March 28, 2019
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hitoshi YAMAMOTO, Tomofumi YOKOYAMA
  • Publication number: 20190097267
    Abstract: A solid electrolyte capable of securing grain boundary resistance even when firing is performed at a relatively low temperature and a battery using the solid electrolyte are provided. The solid electrolyte includes a first electrolyte which contains a lithium composite metal compound, and a second electrolyte which contains Li and at least two kinds of metal elements selected from group 5 elements in period 5 or higher or group 15 elements in period 5 or higher.
    Type: Application
    Filed: March 10, 2017
    Publication date: March 28, 2019
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Tomofumi YOKOYAMA, Hitoshi YAMAMOTO
  • Publication number: 20190084887
    Abstract: A solid electrolyte capable of securing grain boundary resistance even when sintering is performed at a relatively low temperature and a lithium ion battery using the solid electrolyte are provided. The solid electrolyte includes a first electrolyte which contains a lithium composite metal compound containing one kind of first metal element selected from group 13 elements in period 3 or higher, and a second electrolyte which contains Li and at least two kinds of second metal elements selected from group 5 elements in period 5 or higher or group 15 elements in period 5 or higher.
    Type: Application
    Filed: March 13, 2017
    Publication date: March 21, 2019
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hitoshi YAMAMOTO, Tomofumi YOKOYAMA
  • Publication number: 20180375150
    Abstract: An electrolyte includes a first electrolyte, in which an element constituting a crystalline lithium composite metal oxide represented by the following compositional formula (1) is substituted with a first metal element having a crystal radius of 78 pm or more, and an amorphous second electrolyte, which contains Li and a second metal element contained in the first electrolyte other than Li. (Li7?3x+yGax)(La3?yCay)Zr2O12??(1) (In the formula (1), x and y satisfy the following formulae: 0.1?x?0.6 and 0.0<y?0.3).
    Type: Application
    Filed: June 1, 2018
    Publication date: December 27, 2018
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hitoshi YAMAMOTO, Tomofumi YOKOYAMA
  • Patent number: 10096818
    Abstract: An electrode complex includes: a complex which includes a porous active material molded body which is formed by being three-dimensionally connected with a plurality of particulate active material particles containing a lithium double oxide and a plurality of particulate noble metal particles containing a noble metal with a melting point of 1000° C. or higher and includes a communication hole, and a solid electrolyte layer formed on the surface of the active material molded body containing the communication hole of the active material molded body; and a current collector which is provided by being bonded to the active material molded body on one surface of the complex.
    Type: Grant
    Filed: September 17, 2015
    Date of Patent: October 9, 2018
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Tsutomu Teraoka, Tomofumi Yokoyama
  • Publication number: 20180269532
    Abstract: A manufacturing method of an electrode assembly capable of easily manufacturing a configuration in which an electrolyte and an active material are bonded to each other. A step of supplying, solidifying, and crystallizing a solid electrolyte including Li2+XC1?XBXO3 (X represents a real number equal to or greater than 0 and smaller than 1), so as to be in contact with an active material aggregate including a communication hole between active material particles, is included. In a case where the solid electrolyte is melted, the solid electrolyte is heated in a range of 650 degrees to 900 degrees.
    Type: Application
    Filed: September 26, 2016
    Publication date: September 20, 2018
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Tsutomu TERAOKA, Tomofumi YOKOYAMA, Hitoshi YAMAMOTO, Tomoyuki OKUYAMA
  • Patent number: 10056616
    Abstract: A manufacturing method of an electrode assembly includes forming an active material molded body which contains lithium double oxide and includes plural voids, forming a solid electrolyte in the plural voids, and attaching a polymer gel film impregnated with an electrolytic solution for conducting lithium ions to the active material molded body in which the solid electrolyte is formed.
    Type: Grant
    Filed: February 4, 2015
    Date of Patent: August 21, 2018
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Tsutomu Teraoka, Tomofumi Yokoyama, Hirofumi Hokari
  • Publication number: 20180183098
    Abstract: A polymer electrolyte according to the invention is represented by the following formula (1). In the formula (1), R1 and R2 are each independently hydrogen or CH3, R3 is any of C2H4, CH(CH3)CH2, and (CH2)3, m and n are each a copolymerization ratio of a structural unit in parentheses, and when m and n are set as follows: m+n=10, m and n satisfy the following formulae: 1?m?5 and 5?n?9, and p is 2 or more and 8 or less.
    Type: Application
    Filed: December 14, 2017
    Publication date: June 28, 2018
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hitoshi YAMAMOTO, Tomofumi YOKOYAMA
  • Publication number: 20180151915
    Abstract: A polyelectrolyte composition is represented by the following formula (1). In the formula (1), R1 is hydrogen or CH3, R2 is any of C2H4, CH(CH3)CH2, and (CH2)3, m and n are each a copolymerization ratio of a structural unit in parentheses, and when m and n are set as follows: m+n=10, m and n satisfy the following formulae: 1?m?5 and 5?n?9, and p is 2 or more and 8 or less.
    Type: Application
    Filed: November 6, 2017
    Publication date: May 31, 2018
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hitoshi YAMAMOTO, Tomofumi YOKOYAMA
  • Patent number: 9929428
    Abstract: A polymer solid electrolyte is provided that includes anatase-type titanium oxide, a lithium electrolyte salt, and an ion conductive polymer that binds the titanium oxide.
    Type: Grant
    Filed: May 2, 2012
    Date of Patent: March 27, 2018
    Assignee: SEIKO EPSON CORPORATION
    Inventor: Tomofumi Yokoyama
  • Publication number: 20180062200
    Abstract: A electrolyte is an electrolyte represented by the following formula (1): (Li7?3x+yGax)(La3?yCay)Zr2O12??(1) wherein 0.1?x?1, and 0.01?y?0.5.
    Type: Application
    Filed: August 8, 2017
    Publication date: March 1, 2018
    Applicant: SEIKO EPSON CORPORATION
    Inventors: Hitoshi YAMAMOTO, Tomofumi YOKOYAMA
  • Patent number: 9831524
    Abstract: A manufacturing method of an electrode assembly includes: forming an active material compact containing a lithium double oxide and having a plurality of voids; forming a first solid electrolyte in the plurality of voids; impregnating a precursor solution of a second amorphous solid electrolyte conducting lithium ions with an active material compact in which the first solid electrolyte is formed; and performing heat treatment of the active material compact with which the precursor solution is impregnated and forming a second solid electrolyte in the plurality of voids.
    Type: Grant
    Filed: January 27, 2015
    Date of Patent: November 28, 2017
    Assignee: SEIKO EPSON CORPORATION
    Inventors: Tsutomu Teraoka, Tomofumi Yokoyama
  • Patent number: 9831530
    Abstract: An electrode assembly includes a composite body which includes an active material layer containing an active material constituted by a transition metal oxide, a solid electrolyte layer (solid electrolyte portion) containing a solid electrolyte, and a multiple oxide molded body (multiple oxide portion) containing at least one of a metal multiple oxide represented by the following general formula (1): Ln2Li0.5M0.5O4 (wherein Ln represents a lanthanoid, and M represents a transition metal) and a derivative thereof, and a current collector which is provided on one face (one of the faces) of the composite body by being bonded to the active material layer, wherein in the composite body, the multiple oxide molded body, the active material layer, and the solid electrolyte layer are formed in contact with each other in this order from the side of the one face of the composite body.
    Type: Grant
    Filed: May 31, 2016
    Date of Patent: November 28, 2017
    Assignee: SEIKO EPSON CORPORATION
    Inventor: Tomofumi Yokoyama