Patents by Inventor Toshikatsu Kojima

Toshikatsu Kojima 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: 11348934
    Abstract: According to one embodiment, a memory system includes a semiconductor memory and a controller. The semiconductor memory includes blocks each containing memory cells. The controller is configured to instruct the semiconductor memory to execute a first operation and a second operation. In the first operation and the second operation, the semiconductor memory selects at least one of the blocks, and applies at least one voltage to all memory cells contained in said selected blocks. A number of blocks to which said voltage is applied per unit time in the second operation is larger than that in the first operation.
    Type: Grant
    Filed: February 23, 2021
    Date of Patent: May 31, 2022
    Assignee: Kioxia Corporation
    Inventors: Takehiko Amaki, Yoshihisa Kojima, Toshikatsu Hida, Marie Grace Izabelle Angeles Sia, Riki Suzuki, Shohei Asami
  • Patent number: 10906869
    Abstract: An organic sulfur material comprising carbon, hydrogen, oxygen, and sulfur as constituent elements, and having peaks in the vicinity of 482 cm?1, 846 cm?1, 1066 cm?1, 1279 cm?1, and 1442 cm?1 in a Raman spectrum detected by Raman spectroscopy, the peak in the vicinity of 1442 cm?1 being most intense, has a high capacity and high heat resistance, although a liquid organic starting material is used.
    Type: Grant
    Filed: March 31, 2016
    Date of Patent: February 2, 2021
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Hiroshi Senoh, Toshikatsu Kojima, Nobuhiko Takeichi, Hisanori Ando
  • Patent number: 10847279
    Abstract: An object of the present invention is to provide a novel sulfur-based positive-electrode active material which can largely improve cyclability of a lithium-ion secondary battery, a positive electrode comprising the positive-electrode active material and a lithium-ion secondary battery comprising the positive electrode. The sulfur-based positive-electrode active material is one comprising: a carbon skeleton derived from a polymer composed of a monomer unit having at least one hetero atom-containing moiety, and sulfur incorporated into the carbon skeleton as the carbon skeleton is formed from the polymer by heat treatment.
    Type: Grant
    Filed: March 11, 2019
    Date of Patent: November 24, 2020
    Assignees: SUMITOMO RUBBER INDUSTRIES, LTD., NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Tatsuya Kubo, Toshikatsu Kojima, Tetsuo Sakai, Akihiro Yamano, Masahiro Yanagida
  • Patent number: 10710960
    Abstract: The present invention provides an organic sulfur material comprising carbon, hydrogen, and sulfur as constituent elements, and having peaks in the vicinity of 480 cm?1, 1250 cm?1, 1440 cm?1, and 1900 cm?1 in a Raman spectrum detected by Raman spectroscopy. The peak in the vicinity of 1440 cm?1 is the most intense peak. This organic sulfur material, which is produced by using a liquid organic starting material, achieves high capacity. This organic sulfur material preferably does not have peaks in the vicinity of 846 cm?1 or 1066 cm?1.
    Type: Grant
    Filed: March 24, 2016
    Date of Patent: July 14, 2020
    Assignee: National Institute of Advanced Industrial Science and Technology
    Inventors: Tomonari Takeuchi, Toshikatsu Kojima, Hiroyuki Kageyama
  • Patent number: 10505194
    Abstract: An object of the present invention is to provide a novel positive electrode which is produced using a rubber being an inexpensive material and is capable of enhancing a charge and discharge capacity and cyclability of a lithium-ion secondary battery, and the lithium-ion secondary battery composed of the positive electrode. In the lithium-ion secondary battery, the positive electrode comprises a current collector and an electrode layer formed on a surface of the current collector, the electrode layer comprises an active material, an electrically-conductive additive and a thermosetting resin binder subjected to thermosetting, and the active material comprises a sulfur-based positive-electrode active material prepared by heat-treating a starting material comprising a rubber and sulfur under a non-oxidizing atmosphere.
    Type: Grant
    Filed: February 28, 2019
    Date of Patent: December 10, 2019
    Assignees: SUMITOMO RUBBER INDUSTRIES, LTD., NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Tatsuya Kubo, Akihiro Yamano, Naoto Yamashita, Toshikatsu Kojima, Masahiro Yanagida
  • Publication number: 20190207210
    Abstract: An object of the present invention is to provide a novel sulfur-based positive-electrode active material which can largely improve cyclability of a lithium-ion secondary battery, a positive electrode comprising the positive-electrode active material and a lithium-ion secondary battery comprising the positive electrode. The sulfur-based positive-electrode active material is one comprising: a carbon skeleton derived from a polymer composed of a monomer unit having at least one hetero atom-containing moiety, and sulfur incorporated into the carbon skeleton as the carbon skeleton is formed from the polymer by heat treatment.
    Type: Application
    Filed: March 11, 2019
    Publication date: July 4, 2019
    Applicants: SUMITOMO RUBBER INDUSTRIES, LTD., NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Tatsuya KUBO, Toshikatsu KOJIMA, Tetsuo SAKAI, Akihiro YAMANO, Masahiro YANAGIDA
  • Publication number: 20190198877
    Abstract: An object of the present invention is to provide a novel positive electrode which is produced using a rubber being an inexpensive material and is capable of enhancing a charge and discharge capacity and cyclability of a lithium-ion secondary battery, and the lithium-ion secondary battery composed of the positive electrode. In the lithium-ion secondary battery, the positive electrode comprises a current collector and an electrode layer formed on a surface of the current collector, the electrode layer comprises an active material, an electrically-conductive additive and a thermosetting resin binder subjected to thermosetting, and the active material comprises a sulfur-based positive-electrode active material prepared by heat-treating a starting material comprising a rubber and sulfur under a non-oxidizing atmosphere.
    Type: Application
    Filed: February 28, 2019
    Publication date: June 27, 2019
    Applicants: SUMITOMO RUBBER INDUSTRIES, LTD., NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Tatsuya KUBO, Akihiro YAMANO, Naoto YAMASHITA, Toshikatsu KOJIMA, Masahiro YANAGIDA
  • Patent number: 10008722
    Abstract: An object of the present invention is to provide a positive-electrode active material comprising a carbon-sulfur structure which has Raman shift peaks at around 500 cm?1, at around 1,250 cm?1 and at around 1,450 cm?1 in a Raman spectrum, and by using the positive-electrode active material, it is possible to greatly improve cycling characteristics of a lithium-ion secondary battery.
    Type: Grant
    Filed: September 29, 2014
    Date of Patent: June 26, 2018
    Assignees: SUMITOMO RUBBER INDUSTRIES, LTD., NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Kazuo Hochi, Tatsuya Kubo, Tetsuo Sakai, Toshikatsu Kojima
  • Publication number: 20180072665
    Abstract: The present invention provides an organic sulfur material comprising carbon, hydrogen, and sulfur as constituent elements, and having peaks in the vicinity of 480 cm?1, 1250 cm?1, 1440 cm?1, and 1900 cm?1 in a Raman spectrum detected by Raman spectroscopy. The peak in the vicinity of 1440 cm?1 is the most intense peak. This organic sulfur material, which is produced by using a liquid organic starting material, achieves high capacity. This organic sulfur material preferably does not have peaks in the vicinity of 846 cm?1 or 1066 cm?1.
    Type: Application
    Filed: March 24, 2016
    Publication date: March 15, 2018
    Inventors: Tomonari Takeuchi, Toshikatsu Kojima, Hiroyuki Kageyama
  • Publication number: 20180065927
    Abstract: An organic sulfur material comprising carbon, hydrogen, oxygen, and sulfur as constituent elements, and having peaks in the vicinity of 482 cm?1, 846 cm?1, 1066 cm?1, 1279 cm?1, and 1442 cm?1 in a Raman spectrum detected by Raman spectroscopy, the peak in the vicinity of 1442 cm?1 being most intense, has a high capacity and high heat resistance, although a liquid organic starting material is used.
    Type: Application
    Filed: March 31, 2016
    Publication date: March 8, 2018
    Inventors: Hiroshi Senoh, Toshikatsu Kojima, Nobuhiko Takeichi, Hisanori Ando
  • Patent number: 9812702
    Abstract: To provide a lithium ion secondary battery capable of suppressing thermal run-away when internal short circuiting occurs. The lithium ion secondary battery includes: a positive electrode including a current collector, a positive electrode active material layer that is formed on the current collector and that contains a lithium-containing complex oxide having a layered rock salt structure and being represented by general formula: LiaNibCocMndDeOf (0.2?a?1; b+c+d+e=1; 0?e<1; D is at least one element selected from Li, Fe, Cr, Cu, Zn, Ca, Mg, S, Si, Na, K, and Al; 1.7?f?2.1), and a thermal run-away suppressing layer formed on the positive electrode active material layer and containing a lithium transition metal silicate; and a negative electrode including a negative electrode active material. A ratio of the mass of the lithium-containing complex oxide with respect to the mass of the lithium transition metal silicate in the positive electrode is not lower than 1.5.
    Type: Grant
    Filed: July 17, 2014
    Date of Patent: November 7, 2017
    Assignees: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Yuta Ikeuchi, Toshikatsu Kojima, Tetsuo Sakai, Tatsuya Eguchi, Hitoshi Aikiyo, Akira Kojima
  • Publication number: 20170149063
    Abstract: An object of the present invention is to provide a novel positive electrode which is produced using a rubber being an inexpensive material and is capable of enhancing a charge and discharge capacity and cyclability of a lithium-ion secondary battery, and the lithium-ion secondary battery composed of the positive electrode. In the lithium-ion secondary battery, the positive electrode comprises a current collector and an electrode layer formed on a surface of the current collector, the electrode layer comprises an active material, an electrically-conductive additive and a thermosetting resin binder subjected to thermosetting, and the active material comprises a sulfur-based positive-electrode active material prepared by heat-treating a starting material comprising a rubber and sulfur under a non-oxidizing atmosphere.
    Type: Application
    Filed: October 20, 2016
    Publication date: May 25, 2017
    Applicants: SUMITOMO RUBBER INDUSTRIES, LTD., NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Tatsuya KUBO, Akihiro YAMANO, Naoto YAMASHITA, Toshikatsu KOJIMA, Masahiro YANAGIDA
  • 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
  • Publication number: 20170062809
    Abstract: An object of the present invention is to provide a novel sulfur-based positive-electrode active material which can largely improve cyclability of a lithium-ion secondary battery, a positive electrode comprising the positive-electrode active material and a lithium-ion secondary battery comprising the positive electrode. The sulfur-based positive-electrode active material is one comprising: a carbon skeleton derived from a polymer composed of a monomer unit having at least one hetero atom-containing moiety, and sulfur incorporated into the carbon skeleton as the carbon skeleton is formed from the polymer by heat treatment.
    Type: Application
    Filed: August 3, 2016
    Publication date: March 2, 2017
    Applicants: SUMITOMO RUBBER INDUSTRIES, LTD., NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Tatsuya KUBO, Toshikatsu KOJIMA, Tetsuo SAKAI, Akihiro YAMANO, Masahiro YANAGIDA
  • 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
  • Publication number: 20160293955
    Abstract: An object of the present invention is to provide a positive-electrode active material comprising a carbon-sulfur structure which has Raman shift peaks at around 500 cm?1, at around 1,250 cm?1 and at around 1,450 cm?1 in a Raman spectrum, and by using the positive-electrode active material, it is possible to greatly improve cycling characteristics of a lithium-ion secondary battery.
    Type: Application
    Filed: September 29, 2014
    Publication date: October 6, 2016
    Applicants: SUMITOMO RUBBER INDUSTRIES, LTD., NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Kazuo HOCHI, Tatsuya KUBO, Tetsuo SAKAI, Toshikatsu KOJIMA
  • Publication number: 20160204421
    Abstract: To provide a lithium ion secondary battery capable of suppressing thermal run-away when internal short circuiting occurs. The lithium ion secondary battery includes: a positive electrode including a current collector, a positive electrode active material layer that is formed on the current collector and that contains a lithium-containing complex oxide having a layered rock salt structure and being represented by general formula: LiaNibCocMndDeOf (0.2?a?1; b+c+d+e=1; 0?e<1; D is at least one element selected from Li, Fe, Cr, Cu, Zn, Ca, Mg, S, Si, Na, K, and Al; 1.7?f?2.1), and a thermal run-away suppressing layer formed on the positive electrode active material layer and containing a lithium transition metal silicate; and a negative electrode including a negative electrode active material. A ratio of the mass of the lithium-containing complex oxide with respect to the mass of the lithium transition metal silicate in the positive electrode is not lower than 1.5.
    Type: Application
    Filed: July 17, 2014
    Publication date: July 14, 2016
    Applicants: KABUSHIKI KAISHA TOYOTA JIDOSHOKKI, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventors: Yuta IKEUCHI, Toshikatsu KOJIMA, Tetsuo SAKAI, Tatsuya EGUCHI, Hitoshi AIKIYO, Akira KOJIMA
  • 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
  • Patent number: 9269954
    Abstract: The present invention is one which provides a production process for lithium-silicate-system compound, the production process being characterized in that: a lithium-silicate compound being expressed by Li2SiO3 is reacted with a substance including at least one member of transition-metal elements that is selected from the group consisting of iron and manganese 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 mixed-gas atmosphere including carbon dioxide and a reducing gas; and a positive-electrode active material for lithium-ion secondary battery that comprises a lithium-silicate-system compound being obtained by the aforesaid process.
    Type: Grant
    Filed: November 20, 2009
    Date of Patent: February 23, 2016
    Assignees: NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY, KABUSHIKI KAISHA TOYOTA JIDOSHOKKI
    Inventors: Toshikatsu Kojima, Tetsuo Sakai, Takuhiro Miyuki, Yasue Okuyama, Akira Kojima, Junichi Niwa, Hitotoshi Murase