Patents by Inventor Kazuhito Kawasumi

Kazuhito Kawasumi 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: 9997772
    Abstract: Providing a negative-electrode material for nonaqueous-electrolyte secondary battery, the negative-electrode material including lithium silicate particles coated by a carbonaceous substance, a production process for the same, a negative electrode for nonaqueous-electrolyte secondary battery, and a nonaqueous-electrolyte secondary battery. A negative-electrode material for nonaqueous-electrolyte secondary battery includes lithium silicate particles having a surface at least some of which is coated by a carbonaceous substance formed by heating a carbon-containing compound at a thermal decomposition temperature of the carbon-containing compound or more and 1,100±° C. or less, the carbon-containing compound being a solid at ordinary temperature and exhibiting a zeta-potential absolute value being 60 or more against N-methyl-2-pyrrolidone (or NMP).
    Type: Grant
    Filed: August 23, 2013
    Date of Patent: June 12, 2018
    Assignee: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Tomohiro Niimi, Yusuke Sugiyama, Nagisa Watanabe, Kazuhito Kawasumi, Masakazu Murase, Masataka Nakanishi
  • Patent number: 9590237
    Abstract: A lithium-ion secondary battery of the present invention comprises a positive electrode including a positive electrode active material composite formed by compositing a lithium silicate-based material and a carbon material, a negative electrode including a negative electrode active material containing a silicon, and an electrolyte. The lithium-ion secondary battery satisfies 0.8<B/A<1.2, where A is irreversible capacity of the positive electrode and B is irreversible capacity of the negative electrode.
    Type: Grant
    Filed: January 8, 2014
    Date of Patent: March 7, 2017
    Assignees: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Akira Kojima, Junichi Niwa, Kazuhito Kawasumi, Yuta Ikeuchi, Masanori Morishita, Toshikatsu Kojima, Tetsuo Sakai
  • Patent number: 9583765
    Abstract: Provided are a positive electrode active material for a sodium ion secondary battery, and a positive electrode and a sodium ion secondary battery using the material. The positive electrode active material for a sodium ion secondary battery comprises a lithium sodium-based compound containing lithium (Li), sodium (Na), iron (Fe), and oxygen (O).
    Type: Grant
    Filed: April 8, 2014
    Date of Patent: February 28, 2017
    Assignees: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Akira Kojima, Kazuhito Kawasumi, Junichi Niwa, Yuta Ikeuchi, Toshikatsu Kojima, Tetsuo Sakai
  • Patent number: 9444100
    Abstract: In a secondary battery, a negative electrode, an electrolytic solution for negative electrode, a diaphragm, an electrolytic solution for positive electrode, and a positive electrode are disposed in order. The negative electrode includes a negative-electrode active material that has an element whose oxidation-reduction potential is more “base” by 1.5 V or more than an oxidation-reduction potential of hydrogen, and whose volume density is larger than that of lithium metal. The diaphragm includes a solid electrolyte transmitting ions of said element alone. A secondary battery with high volumetric density is provided.
    Type: Grant
    Filed: September 21, 2012
    Date of Patent: September 13, 2016
    Assignee: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Junichi Niwa, Masataka Nakanishi, Kazuhito Kawasumi, Masakazu Murase
  • Patent number: 9330805
    Abstract: Provided is a novel lithium silicate-based material useful as a positive electrode material for lithium ion secondary battery. The lithium silicate-based compound is represented by Li1.5FeSiO4.25. The lithium silicate-based compound is a compound including: lithium (Li); iron (Fe); silicon (Si); and oxygen (O), and expressed by a composition formula, Li1+2?FeSiO4+??c (?0.25???0.25, 0?c?0.5). The lithium silicate-based compound, of which iron (Fe) is trivalent, exerts a remarkable chemical stability as compared to Li2FeSiO4.
    Type: Grant
    Filed: July 26, 2012
    Date of Patent: May 3, 2016
    Assignees: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Akira Kojima, Toshikatsu Kojima, Mitsuharu Tabuchi, Tetsuo Sakai, Masanori Morishita, Takuhiro Miyuki, Junichi Niwa, Masataka Nakanishi, Yuya Sato, Kazuhito Kawasumi, Masakazu Murase
  • Patent number: 9315390
    Abstract: A production process for lithium-silicate-based compound according to the present invention is characterized in that: a lithium-silicate compound being expressed by Li2SiO3 is reacted with a transition-metal-element-containing substance including at least one member being selected from the group consisting of iron and manganese at 550° C. or less within a molten salt including at least one member being selected from the group consisting of alkali-metal nitrates as well as alkali-metal hydroxides in an atmosphere in the presence of a mixed gas including carbon dioxide and a reducing gas. In accordance with the present invention, it is possible to produce lithium-silicate-based materials, which are useful as a positive-electrode active material for lithium-ion secondary battery, and the like, at low temperatures by means of relatively easy means.
    Type: Grant
    Filed: June 17, 2011
    Date of Patent: April 19, 2016
    Assignees: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Toshikatsu Kojima, Takuhiro Miyuki, Tetsuo Sakai, Akira Kojima, Junichi Niwa, Hitotoshi Murase, Kazuhito Kawasumi
  • Publication number: 20150380729
    Abstract: A lithium-ion secondary battery of the present invention comprises a positive electrode including a positive electrode active material composite formed by compositing a lithium silicate-based material and a carbon material, a negative electrode including a negative electrode active material containing a silicon, and an electrolyte. The lithium-ion secondary battery satisfies 0.8<B/A<1.2, where A is irreversible capacity of the positive electrode and B is irreversible capacity of the negative electrode.
    Type: Application
    Filed: January 8, 2014
    Publication date: December 31, 2015
    Applicants: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Akira KOJIMA, Junichi NIWA, Kazuhito KAWASUMI, Yuta IKEUCHI, Masanori MORISHITA, Toshikatsu KOJIMA, Tetsuo SAKAI
  • Patent number: 9190186
    Abstract: Providing a negative-electrode active material for nonaqueous-electrolyte secondary battery, the negative-electrode active material enabling an output characteristic to upgrade, a production process for the same, a negative electrode for nonaqueous-electrolyte secondary battery, and a nonaqueous-electrolyte secondary battery. The negative-electrode active material includes an Si-metal-carbon composite composed of: a metal/carbon composite matrix including at least one metal selected from the group consisting of Cu, Fe, Ni, Ti, Nb, Zn, In and Sn, at least one member selected from the group consisting of N, O, P and S, and amorphous carbon; and nanometer-size Si particles dispersed in the metal/carbon composite matrix.
    Type: Grant
    Filed: April 10, 2013
    Date of Patent: November 17, 2015
    Assignee: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Yusuke Sugiyama, Tomohiro Niimi, Masataka Nakanishi, Hirotaka Sone, Kazuhito Kawasumi, Masakazu Murase
  • Patent number: 9082525
    Abstract: A lithium silicate-based compound according to the present invention is expressed by a general formula, Li(2?a+b)AaMn(1?x?y)CoxMySiO(4+?)Cl? (In the formula: “A” is at least one element selected from the group consisting of Na, K, Rb and Cs; “M” is at least one member selected from the group consisting of Mg, Ca, Al, Ni, Fe, Nb, Ti, Cr, Cu, Zn, Zr, V, Mo and W; and the respective subscripts appear to be as follows: 0?“a”<0.2; 0?“b”<1; 0<“x”<1; 0?“y”?0.5; ?0.25?“?”?1.25; and 0?“?”?0.05). The lithium silicate-based compound is used as a positive-electrode active material for secondary battery whose discharge average voltage is higher, and which is able to sorb and desorb lithium ions.
    Type: Grant
    Filed: October 12, 2012
    Date of Patent: July 14, 2015
    Assignees: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Akira Kojima, Toshikatsu Kojima, Mitsuharu Tabuchi, Tetsuo Sakai, Takuhiro Miyuki, Junichi Niwa, Kazuhito Kawasumi, Masakazu Murase
  • Publication number: 20150188127
    Abstract: Providing a negative-electrode material for nonaqueous-electrolyte secondary battery, the negative-electrode material including lithium silicate particles coated by a carbonaceous substance, a production process for the same, a negative electrode for nonaqueous-electrolyte secondary battery, and a nonaqueous-electrolyte secondary battery. A negative-electrode material for nonaqueous-electrolyte secondary battery includes lithium silicate particles having a surface at least some of which is coated by a carbonaceous substance formed by heating a carbon-containing compound at a thermal decomposition temperature of the carbon-containing compound or more and 1,100° C. or less, the carbon-containing compound being a solid at ordinary temperature and exhibiting a zeta-potential absolute value being 60 or more against N-methyl-2-pyrrolidone (or NMP).
    Type: Application
    Filed: August 23, 2013
    Publication date: July 2, 2015
    Applicant: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Tomohiro Niimi, Yusuke Sugiyama, Nagisa Watanabe, Kazuhito Kawasumi, Masakazu Murase, Masataka Nakanishi
  • Publication number: 20150111110
    Abstract: A solid electrolyte has a sheet shape, and is composed of an oxide sintered body. The solid electrolyte includes a layer-shaped dense portion whose sintered density is 90% or more, and a porous portion formed on a superficial side of the solid electrolyte so as to be continuous from at least one of opposite surfaces of the dense portion, and having a porosity of 50% or more. A secondary battery includes a positive electrode, and a negative electrode, the positive electrode and negative electrode arranged at opposite facing positions interposing the solid electrolyte.
    Type: Application
    Filed: April 25, 2013
    Publication date: April 23, 2015
    Applicant: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Nagisa Watanabe, Kazuhito Kawasumi, Junichi Niwa, Masataka Nakanishi
  • Publication number: 20150076399
    Abstract: Providing a negative-electrode active material for nonaqueous-electrolyte secondary battery, the negative-electrode active material enabling an output characteristic to upgrade, a production process for the same, a negative electrode for nonaqueous-electrolyte secondary battery, and a nonaqueous-electrolyte secondary battery. The negative-electrode active material includes an Si-metal-carbon composite composed of: a metal/carbon composite matrix including at least one metal selected from the group consisting of Cu, Fe, Ni, Ti, Nb, Zn, In and Sn, at least one member selected from the group consisting of N, O, P and S, and amorphous carbon; and nanometer-size Si particles dispersed in the metal/carbon composite matrix.
    Type: Application
    Filed: April 10, 2013
    Publication date: March 19, 2015
    Applicant: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Yusuke Sugiyama, Tomohiro Niimi, Masataka Nakanishi, Hirotaka Sone, Kazuhito Kawasumi, Masakazu Murase
  • Publication number: 20140356731
    Abstract: In a secondary battery, a negative electrode, an electrolytic solution for negative electrode, a diaphragm, an electrolytic solution for positive electrode, and a positive electrode are disposed in order. The negative electrode includes a negative-electrode active material that has an element whose oxidation-reduction potential is more “base” by 1.5 V or more than an oxidation-reduction potential of hydrogen, and whose volume density is larger than that of lithium metal. The diaphragm includes a solid electrolyte transmitting ions of said element alone. A secondary battery with high volumetric density is provided.
    Type: Application
    Filed: September 21, 2012
    Publication date: December 4, 2014
    Applicant: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Junichi Niwa, Masataka Nakanishi, Kazuhito Kawasumi, Masakazu Murase
  • Publication number: 20140332718
    Abstract: A lithium silicate-based compound according to the present invention is expressed by a general formula, Li(2?a+b)AaMn(1?x?y)CoxMySiO(4+?)Cl? (In the formula: “A” is at least one element selected from the group consisting of Na, K, Rb and Cs; “M” is at least one member selected from the group consisting of Mg, Ca, Al, Ni, Fe, Nb, Ti, Cr, Cu, Zn, Zr, V, Mo and W; and the respective subscripts appear to be as follows: 0?“a”<0.2; 0?“b”<1; 0<“x”<1; 0?“y”?0.5; ?0.25?“?”?1.25; and 0?“?”?0.05). The lithium silicate-based compound is used as a positive-electrode active material for secondary battery whose discharge average voltage is higher, and which is able to sorb and desorb lithium ions.
    Type: Application
    Filed: October 12, 2012
    Publication date: November 13, 2014
    Applicants: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Akira Kojima, Toshikatsu Kojima, Mitsuharu Tabuchi, Tetsuo Sakai, Takuhiro Miyuki, Junichi Niwa, Kazuhito Kawasumi, Masakazu Murase
  • Publication number: 20140308579
    Abstract: Provided are a positive electrode active material for a sodium ion secondary battery, and a positive electrode and a sodium ion secondary battery using the material. The positive electrode active material for a sodium ion secondary battery comprises a lithium sodium-based compound containing lithium (Li), sodium (Na), iron (Fe), and oxygen (O).
    Type: Application
    Filed: April 8, 2014
    Publication date: October 16, 2014
    Applicants: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Akira KOJIMA, Kazuhito KAWASUMI, Junichi NIWA, Yuta IKEUCHI, Toshikatsu KOJIMA, Tetsuo SAKAI
  • Publication number: 20140231721
    Abstract: Provided is a novel lithium silicate-based material useful as a positive electrode material for lithium ion secondary battery. The lithium silicate-based compound is represented by Li1.5FeSiO4.25 The lithium silicate-based compound is a compound including: lithium (Li); iron (Fe); silicon (Si); and oxygen (O), and expressed by a composition formula, Li1+2?FeSiO4+??c(?0.25???0.25, 0?c?0.5). The lithium silicate-based compound, of which iron (Fe) is trivalent, exerts a remarkable chemical stability as compared to Li2FeSiO4.
    Type: Application
    Filed: July 26, 2012
    Publication date: August 21, 2014
    Applicants: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Akira Kojima, Toshikatsu Kojima, Mitsuharu Tabuchi, Tetsuo Sakai, Masanori Morishita, Takuhiro Miyuki, Junichi Niwa, Masataka Nakanishi, Yuya Sato, Kazuhito Kawasumi, Masakazu Murase
  • Patent number: 8728663
    Abstract: To provide a sulfur-system positive electrode for lithium-ion battery, sulfur-system positive electrode which is good in the cyclability and the other characteristics, and a lithium-ion secondary battery including that positive electrode. In a positive electrode for lithium-ion secondary battery, the positive electrode having: a current collector; and an electrode layer that is formed on a surface of the current collector, and which includes a binder resin, an active material and a conductive additive, the positive electrode is characterized in that the active material includes a sulfur-modified polyacrylonitrile that is produced by heating a raw-material powder including a sulfur powder and a polyacrylonitrile powder in an enclosed nonoxidizing atmosphere; and the binder resin includes a polyimide resin and/or a polyamide-imide resin.
    Type: Grant
    Filed: April 12, 2011
    Date of Patent: May 20, 2014
    Assignees: Kabushiki Kaisha Toyota Jidoshokki, National Institute of Advanced Industrial Science and Technology
    Inventors: Junichi Niwa, Kazuaki Hokano, Masataka Nakanishi, Akira Kojima, Kazuhito Kawasumi, Takuhiro Miyuki, Tetsuo Sakai
  • Publication number: 20140134485
    Abstract: A negative-electrode active material for secondary battery includes a sulfur-modified polyacrylonitrile. The sulfur-modified polyacrylonitrile includes a polyacrylonitrile, and sulfur being introduced into the polyacrylonitrile.
    Type: Application
    Filed: November 8, 2013
    Publication date: May 15, 2014
    Applicants: National Institute of Advanced Industrial Science and Technology, Kabushiki Kaisha Toyota Jidoshokki
    Inventors: Takuhiro MIYUKI, Toshikatsu KOJIMA, Yuta IKEUCHI, Masanori MORISHITA, Tetsuo SAKAI, Kazuhito KAWASUMI, Masataka NAKANISHI, Junichi NIWA
  • Publication number: 20140127585
    Abstract: It is intended to provide a positive electrode active material, which contains a lithium silicate based compound and has superior conductivity, for nonaqueous electrolyte secondary battery, a process for producing the same, and a nonaqueous electrolyte secondary battery using the positive electrode active material. The lithium silicate based compound and a carbon material are mixed at 450 to 16000 rpm for 1 minute to 10 hours and then heated and pressurized at 500° C. to 700° C. at 1 to 500 MPa for 1 minute to 15 hours, thereby adhering the lithium silicate based compound and the carbon material to each other.
    Type: Application
    Filed: March 16, 2012
    Publication date: May 8, 2014
    Applicants: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Akira Kojima, Toshikatsu Kojima, Tomonari Takeuchi, Tetsuo Sakai, Takuhiro Miyuki, Junichi Niwa, Kazuhito Kawasumi
  • Publication number: 20140050974
    Abstract: Because of being equipped with a positive electrode, a negative electrode and a sodium-ion nonaqueous electrolyte, and because the positive electrode includes a sulfur-based positive-electrode active material containing carbon (C) and sulfur (S), it is possible to inhibit sulfur from eluting out into electrolytic solution, thereby resulting in a sodium secondary battery that makes it feasible to undergo charging and discharging for 100 cycles or more reversibly.
    Type: Application
    Filed: January 12, 2012
    Publication date: February 20, 2014
    Applicants: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Takuhiro Miyuki, Toshikatsu Kojima, Yasue Okuyama, Tetsuo Sakai, Masataka Nakanishi, Junichi Niwa, Kazuhito Kawasumi, Satoshi Nakagawa, Akira Kojima