Patents by Inventor Junichi Niwa

Junichi Niwa 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: 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: 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
  • Patent number: 8940436
    Abstract: Provided is a sulfur-modified polyacrylonitrile manufacturing method that is characterized in that a starting base powder that comprises sulfur powder and polyacrylonitrile powder is mixed and the mixture is heated in a non-oxidizing environment while outflow of sulfur vapor is prevented. Also provided are a cathode for lithium batteries that uses, as the active substance, the sulfur-modified polyacrylonitrile manufactured with the method, and a lithium secondary battery that includes the cathode as a component element. This enables the practical use of an inexpensive sulfur-based material as the cathode material for lithium secondary batteries, and in particular, a sulfur-based cathode material that enables higher output and has excellent cycle life characteristics, as well as other characteristics, and secondary lithium batteries using the same can be obtained.
    Type: Grant
    Filed: October 15, 2009
    Date of Patent: January 27, 2015
    Assignees: National Institute of Advanced Industrial Science and Technology, Kabushiki Kaisha Toyota Jidoshokki
    Inventors: Takuhiro Miyuki, Tetsuo Sakai, Junichi Niwa, Hitotoshi Murase
  • Patent number: 8927157
    Abstract: Provided is a condensed polycyclic aromatic compound, having lithium ion responsivity and is suitable for lithium ion secondary battery applications, a production process thereof, a positive electrode active material containing that condensed polycyclic aromatic compound, and a positive electrode for a lithium ion secondary battery provided therewith, and further provided is a lithium ion secondary battery, having high capacity and cycling adaptability, that has the positive electrode as a constituent thereof. The condensed polycyclic aromatic compound has at least four imino groups in a molecule thereof.
    Type: Grant
    Filed: May 26, 2011
    Date of Patent: January 6, 2015
    Assignees: Kabushiki Kaisha Toyota Jidoshokki, Keio University
    Inventors: Osamu Ohmori, Akiko Shima, Hitotoshi Murase, Masataka Nakanishi, Junichi Niwa, Kimihisa Yamamoto
  • 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
  • Publication number: 20140186704
    Abstract: To provide a lithium ion secondary battery electrode in which a coated layer is held on a surface of an active material layer over a long period of time to suppress decomposition of the electrolysis solution and to enhance the cyclability, a manufacturing process for the same, and a lithium ion secondary battery using the electrode. A lithium ion secondary battery electrode includes a current collector, an active material layer containing a binder formed on a surface of the current collector, and a coated layer formed on the surface of at least a part of the active material layer, wherein the coated layer consists of an acrylic type copolymer cured substance comprising an acrylic type main chain and a side chain having polyester or polyether graft-polymerized to said acrylic type main chain and the coated layer is chemically bonded with the binder.
    Type: Application
    Filed: May 2, 2012
    Publication date: July 3, 2014
    Applicant: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Junichi Niwa, Yuichi Hirakawa, Manabu Miyoshi, Keiichi Hayashi, Hitotoshi 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: 20140099542
    Abstract: To provide a lithium ion secondary battery electrode in which a coated layer is held on a surface of an active material layer over a long period of time to suppress decomposition of the electrolysis solution and to enhance the cyclability, a manufacturing process for the same, and a lithium ion secondary battery using the electrode. A lithium ion secondary battery electrode includes a current collector, an active material layer containing a binder formed on a surface of the current collector, and a coated layer formed on the surface of at least a part of the active material layer, wherein the coated layer contains a silicone-acrylic graft copolymer cured substance including an acrylic type main chain having a functional group and a side chain having a silicone graft-polymerized to the acrylic type main chain, and the coated layer is chemically bonded with the binder.
    Type: Application
    Filed: May 2, 2012
    Publication date: April 10, 2014
    Applicant: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Junichi Niwa, Yuichi Hirakawa, Manabu Miyoshi, Keiichi Hayashi, Hitotoshi Murase
  • 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
  • Publication number: 20130183584
    Abstract: A production process for lithium-silicate-based compound is characterized in that: a lithium-silicate compound is reacted with a transition-metal-element-containing substance including iron and/or manganese at from 300° C. or more to 600° C. or less within a molten salt including at least one member being selected from the group consisting of alkali-metal salts under a mixed-gas atmosphere including carbon dioxide and a reducing gas; wherein said transition-metal-element-containing substance includes a deposit that is formed by alkalifying a transition-metal-containing aqueous solution including a compound that includes iron and/or manganese. In accordance with the present production process, lithium-silicate-based compounds including silicon excessively are obtainable.
    Type: Application
    Filed: October 31, 2011
    Publication date: July 18, 2013
    Applicant: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Toshikatsu Kojima, Mitsuharu Tabuchi, Takuhiro Miyuki, Tetsuo Sakai, Akira Kojima, Junichi Niwa, Kazuhito Kawasumi
  • Publication number: 20130078519
    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: Application
    Filed: June 17, 2011
    Publication date: March 28, 2013
    Applicants: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Toshikatsu Kojima, Takuhiro Miyuki, Tetsuo Sakai, Akira Kojima, Junichi Niwa, Hitotoshi Murase, Kazuhito Kawasumi
  • Publication number: 20130078514
    Abstract: Provided is a condensed polycyclic aromatic compound, having superior lithium ion responsivity and is suitable for lithium ion secondary battery applications, a production process thereof, a positive electrode active material containing that condensed polycyclic aromatic compound, and a positive electrode for a lithium ion secondary battery provided therewith, and further provided is a lithium ion secondary battery, having high capacity and superior cycling adaptability, that has the positive electrode as a constituent thereof. The condensed polycyclic aromatic compound according to the present invention has at least four imino groups in a molecule thereof.
    Type: Application
    Filed: May 26, 2011
    Publication date: March 28, 2013
    Applicants: KEIO UNIVERSITY, KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Osamu Ohmori, Akiko Shima, Hitotoshi Murase, Masataka Nakanishi, Junichi Niwa, Kimihisa Yamamoto
  • Publication number: 20130029222
    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: Application
    Filed: April 12, 2011
    Publication date: January 31, 2013
    Applicants: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Junichi Niwa, Kazuaki Hokano, Masataka Nakanishi, Akira Kojima, Kazuhito Kawasumi, Takuhiro Miyuki, Tetsuo Sakai
  • Publication number: 20120321955
    Abstract: A lithium-ion secondary battery is characterized in that it is equipped with: a positive electrode comprising a positive-electrode active material that includes a lithium-transition metal composite oxide including at least lithium and manganese and possessing a layered rock-salt structure; a negative electrode comprising a negative-electrode active material that includes at least one kind of carbon-based materials, silicon-based materials, and tin-based materials; and a non-aqueous electrolytic solution, wherein: said lithium-transition metal composite oxide exhibits an irreversible capacity; and an actual capacity of said negative electrode at the time of first-round charging up to 0 V with respect to metallic lithium is smaller than an actual capacity of said positive electrode at the time of first-round charging up to 4.7 V with respect to metallic lithium.
    Type: Application
    Filed: April 1, 2011
    Publication date: December 20, 2012
    Applicant: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Naoto Yasuda, Toru Abe, Junichi Niwa
  • Publication number: 20110315919
    Abstract: A process is provided, process which makes it possible to produce lithium-borate-system materials by means of relatively simple means, lithium-borate-system materials which are useful as positive-electrode active materials for lithium-ion secondary battery, and the like, whose cyclic characteristics, capacities, and so forth, are improved, and which have better performance. The present production is characterized in that a divalent metallic compound including at least one member of compounds that is selected from the group consisting of divalent-iron compounds and divalent-manganese compounds, and boric acid as well as lithium hydroxide are reacted at 400-650° C. in a molten salt of a carbonate mixture comprising lithium carbonate and at least one member of alkali-metal carbonates that is selected from the group consisting of potassium carbonate, sodium carbonate, rubidium carbonate and cesium carbonate in a reducing atmosphere.
    Type: Application
    Filed: March 4, 2010
    Publication date: December 29, 2011
    Applicants: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Toshikatsu Kojima, Tetsuo Sakai, Takuhiro Miyuki, Akira Kojima, Junichi Niwa, Hitotoshi Murase