Patents by Inventor Daisuke Kawasaki

Daisuke Kawasaki 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: 9325010
    Abstract: Provided is a negative electrode active material for a lithium secondary cell, the material having the function of a binder for the active material, and being capable of stable reversible reactions with lithium. Also, provided are an extended-life lithium secondary cell having improved energy density and stable charge/discharge, and a method for producing the same. The negative electrode active material for a lithium secondary cell is polyimide represented by formula (1) (wherein R1 and R2 independently denote an alkyl, alkoxy, acyl, phenyl, or phenoxy group).
    Type: Grant
    Filed: April 27, 2012
    Date of Patent: April 26, 2016
    Assignee: NEC Corporation
    Inventors: Jiro Iriyama, Tetsuya Kajita, Daisuke Kawasaki, Tatsuji Numata, Kazuhiko Inoue
  • Patent number: 9299985
    Abstract: Provided is a secondary battery having a good battery property at a high temperature. A secondary battery according to an exemplary embodiment of the invention comprises a negative electrode and an electrolyte liquid; wherein the negative electrode is formed by binding a negative electrode active substance on a negative electrode collector with a negative electrode binder; and wherein the electrolyte liquid comprises a compound (A) having a C?S bond. In this embodiment, the negative electrode active substance is formed by covering at least one of a metal (a) that can be alloyed with lithium and a metal oxide (b) that can absorb and desorb a lithium ion with a carbon material (c). Alternatively, the negative electrode active substance comprises a metal (a) that can be alloyed with lithium and the negative electrode binder negative electrode is a polyimide or a polyamide-imide.
    Type: Grant
    Filed: June 23, 2011
    Date of Patent: March 29, 2016
    Assignee: NEC CORPORATION
    Inventors: Yoko Hashizume, Daisuke Kawasaki, Masahiro Suguro, Midori Shimura, Kazuaki Matsumoto
  • Publication number: 20160028123
    Abstract: A nonaqueous electrolyte solution secondary battery having an electrode element having a positive electrode and a negative electrode disposed so as to face each other, a nonaqueous electrolyte solution, and an outer package housing the electrode element and the nonaqueous electrolyte solution, wherein the nonaqueous electrolyte solution contains a cyclic sulfonic acid ester represented by the general formula (1), and a positive electrode active material in the positive electrode is a mixture of a lithium manganese composite oxide having a spinel structure and a lithium transition metal composite compound having a layered rock salt structure.
    Type: Application
    Filed: February 28, 2014
    Publication date: January 28, 2016
    Applicant: NEC Corporation
    Inventors: Daisuke KAWASAKI, Ikiko SHIMANUKI, Noboru YOSHIDA
  • Publication number: 20160028118
    Abstract: Disclosed is an electrolyte solution for lithium secondary batteries, including a cyclic sulfonic acid ester represented by the general formula (1): wherein, in the general formula (1), R1 and R2 each independently represent a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, halogen or an amino group with the proviso that R1 and R2 do not represent hydrogen atoms at the same time; and R3 represents methylene which may be substituted with fluorine. Batteries using this electrolyte solution are excellent in battery properties and storage characteristics.
    Type: Application
    Filed: February 28, 2014
    Publication date: January 28, 2016
    Applicant: NEC CORPORATION
    Inventors: Ikiko SHIMANUKI, Hitoshi ISHIKAWA, Daisuke KAWASAKI
  • Patent number: 9219274
    Abstract: A secondary battery having high capacity and satisfactory high-temperature cycle characteristics is provided. A secondary battery according to the exemplary embodiment has an electrode element in which a positive electrode and a negative electrode are arranged so as to face each other, an electrolytic solution and an outer package packaging the electrode element and the electrolytic solution, wherein the negative electrode is formed by binding a negative electrode active material containing at least one of a metal (a) capable of forming an alloy with lithium and a metal oxide (b) capable of absorbing and releasing lithium ions, to a negative electrode collector, with a polyimide or a polyamide-imide serving as a negative electrode binder; and the electrolytic solution contains a phosphazene compound.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: December 22, 2015
    Assignee: NEC CORPORATION
    Inventors: Daisuke Kawasaki, Masahiro Suguro, Midori Shimura, Kazuaki Matsumoto, Yoko Hashizume
  • Patent number: 9203107
    Abstract: An exemplary embodiment provides a lithium ion secondary battery using a high energy type anode, which enables long-life operation thereof. A secondary battery according to an exemplary embodiment comprises an electrode element in which a cathode and an anode are oppositely disposed, an electrolytic solution, and an outer packaging body which encloses the electrode element and the electrolytic solution inside; wherein the anode is formed by binding an anode active material, which comprises carbon material (a) that can absorb and desorb a lithium ion, metal (b) that can be alloyed with lithium, and metal oxide (c) that can absorb and desorb a lithium ion, to an anode collector with an anode binder; and wherein the electrolytic solution comprises a liquid medium which is hard to generate carbon dioxide at a concentration of 10 to 75 vol %.
    Type: Grant
    Filed: September 29, 2010
    Date of Patent: December 1, 2015
    Assignees: NEC ENERGY DEVICES, LTD., NEC CORPORATION
    Inventors: Daisuke Kawasaki, Shinako Kaneko, Jiro Iriyama
  • Patent number: 9123928
    Abstract: The object of an exemplary embodiment of the invention is to provide a negative electrode having excellent cycle property. An exemplary embodiment of the invention a method for doping and dedoping lithium for the first time after a negative electrode for a lithium secondary battery comprising silicon oxide as an active material is produced, comprising doping the lithium within the following current value range (A) and within the following doped amount range (B); current value range (A): a range of a current value in which a doped amount in which only one peak appears at 1 V or less on the V-dQ/dV curve becomes maximum, wherein the V-dQ/dV curve represents a relationship between voltage V of the negative electrode with respect to a lithium reference electrode and dQ/dV that is a ratio of variation dQ of lithium dedoped amount Q in the negative electrode to variation dV of the voltage V, and doped amount range (B): a range of a doped amount in which only one peak appears at 1 V or less on the V-dQ/dV curve.
    Type: Grant
    Filed: April 6, 2012
    Date of Patent: September 1, 2015
    Assignee: NEC Corporation
    Inventors: Jiro Iriyama, Tetsuya Kajita, Daisuke Kawasaki, Tatsuji Numata
  • Patent number: 9123971
    Abstract: The object of an exemplary embodiment of the invention is to provide a secondary battery with a high performance in which the generation of the swelling can be suppressed and in which the cycle property is excellent. An exemplary embodiment of the invention is a secondary battery, comprising an electrode assembly in which a positive electrode and a negative electrode are oppositely disposed, an electrolyte liquid, and a package which encloses the electrode assembly and the electrolyte liquid inside; wherein the negative electrode is formed by binding a negative electrode active substance, which comprises metal (a) that can be alloyed with lithium, metal oxide (b) that can absorb and desorb lithium ion, and carbon material (c) that can absorb and desorb lithium ion, to a negative electrode collector with at least one selected from polyimides and a polyamide-imides; and wherein the electrolyte liquid comprises a compound represented by any one of predetermined formulae.
    Type: Grant
    Filed: June 23, 2011
    Date of Patent: September 1, 2015
    Assignee: NEC CORPORATION
    Inventors: Midori Shimura, Daisuke Kawasaki, Masahiro Suguro, Yoko Hashizume, Kazuaki Matsumoto
  • Publication number: 20150200425
    Abstract: There is provided a control system for a lithium secondary battery that can quantitatively sense a deterioration state inherent in a lithium secondary battery using silicon oxide as a negative electrode active material, that is, the nonuniform reaction state of a negative electrode.
    Type: Application
    Filed: March 27, 2015
    Publication date: July 16, 2015
    Applicants: NEC ENERGY DEVICES, LTD., NEC CORPORATION
    Inventors: Jiro IRIYAMA, Tetsuya KAJITA, Daisuke KAWASAKI, Ryuichi KASAHARA, Tatsuji NUMATA
  • Patent number: 9076995
    Abstract: A secondary battery according to the present exemplary embodiment is a secondary battery including a laminated electrode body provided with at least one pair of positive and negative electrodes and an outer enclosure that accommodates the laminated electrode body, wherein the outer enclosure includes one or more concave portions, inside a border corresponding to an outer edge of an electrode surface of an outermost layer of the laminated electrode body, on a surface facing the electrode surface, and wherein, when a band-shaped outer circumferential region having an area that is a half of an area inside the border is set inside the border, at least one of the concave portions is located inside the outer circumferential region.
    Type: Grant
    Filed: March 21, 2012
    Date of Patent: July 7, 2015
    Assignee: NEC CORPORATION
    Inventors: Shin Serizawa, Hiroo Takahashi, Daisuke Kawasaki, Jiro Iriyama, Ryuichi Kasahara, Emiko Fujii, Tetsuya Kajita, Tatsuji Numata
  • Patent number: 9077045
    Abstract: An object is to provide a higher-performance secondary battery, particularly to provide a secondary battery having a low impedance. The present exemplary embodiment is a secondary battery comprising an electrode assembly in which a positive electrode and a negative electrode are arranged to face each other, an electrolyte liquid, and a package accommodating the electrode assembly and the electrolyte liquid, wherein the negative electrode includes a negative electrode active substance containing at least one selected from a metal (a) capable of being alloyed with lithium, and a metal oxide (b) capable of occluding and releasing lithium ions, a negative electrode binder, and a negative electrode current collector; and the electrolyte liquid contains a sulfide compound.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: July 7, 2015
    Assignee: NEC CORPORATION
    Inventors: Masahiro Suguro, Daisuke Kawasaki, Midori Shimura, Kazuaki Matsumoto, Yoko Hashizume
  • Publication number: 20150125740
    Abstract: The present invention relates to a lithium ion secondary battery having an electrode element in which a positive electrode and a negative electrode are arranged so as to face each other, an electrolyte and an outer package housing the electrode element and the electrolyte, wherein the negative electrode is formed by using a second negative electrode active material in which lithium is doped into a first negative electrode active material containing a metal (a) capable of forming an alloy with lithium, a metal oxide (b) capable of absorbing and desorbing lithium ions, and a carbon material (c) capable of absorbing and desorbing lithium ions; and the electrolyte contains a fluorinated ether compound represented by a predetermined formula.
    Type: Application
    Filed: May 29, 2013
    Publication date: May 7, 2015
    Applicant: NEC Corporation
    Inventors: Daisuke Kawasaki, Shinya Sudo
  • Patent number: 9018916
    Abstract: There is provided a control system for a lithium secondary battery that can quantitatively sense a deterioration state inherent in a lithium secondary battery using silicon oxide as a negative electrode active material, that is, the nonuniform reaction state of a negative electrode.
    Type: Grant
    Filed: July 20, 2011
    Date of Patent: April 28, 2015
    Assignees: NEC Corporation, NEC Energy Devices, Ltd.
    Inventors: Jiro Iriyama, Tetsuya Kajita, Daisuke Kawasaki, Ryuichi Kasahara, Tatsuji Numata
  • Patent number: 9012093
    Abstract: The present invention provides an electrolyte solution for a lithium ion secondary battery comprising 65 to 99% by volume of a phosphate ester compound, 0.01 to 30% by volume of a fluorinated carbonate compound, and 0.1 to 10% by volume of a halogenated phosphate ester compound and/or 0.1 to 30% by volume of a solvent having a specific dielectric constant of 15 or more, and a lithium ion secondary battery having the same.
    Type: Grant
    Filed: February 25, 2013
    Date of Patent: April 21, 2015
    Assignee: NEC Corporation
    Inventors: Kazuaki Matsumoto, Kazuhiko Inoue, Daisuke Kawasaki
  • Patent number: 8999562
    Abstract: A secondary battery capable of suppressing deterioration of rate characteristics and cycle characteristics even under a high-temperature environment is provided. The secondary battery according to an exemplary embodiment is a secondary battery having an electrode element in which a positive electrode and a negative electrode are arranged so as to face each other, an electrolytic solution and an outer package packaging the electrode element and the electrolytic solution, in which the negative electrode is formed by binding a negative electrode active material to a negative electrode collector, with a negative electrode binder; and the electrolytic solution contains an organic sulfurane compound. The secondary battery electrolytic solution according to the exemplary embodiment contains an organic sulfurane compound.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: April 7, 2015
    Assignee: NEC Corporation
    Inventors: Yoko Hashizume, Daisuke Kawasaki, Masahiro Suguro, Midori Shimura, Kazuaki Matsumoto
  • Publication number: 20150093631
    Abstract: The present invention relates to a secondary battery, comprising an electrode element comprising a positive electrode and a negative electrode placed opposite to each other, an electrolyte, and an outer package housing the electrode element and the electrolyte; wherein the negative electrode is formed by binding a negative electrode active material, which comprises a metal (a) capable of being alloyed with lithium, a metal oxide (b) capable of intercalating/deintercalating lithium ions, and a carbon material (c) capable of intercalating/deintercalating lithium ions, to a negative electrode current collector with a negative electrode binder; and the electrolyte comprises a lithium salt dissolved in a solvent comprising 65 vol % or more of a phosphate ester compound, and more than 0 vol % and less than 20 vol % of a fluorinated carbonate compound.
    Type: Application
    Filed: February 4, 2013
    Publication date: April 2, 2015
    Inventors: Daisuke Kawasaki, Kazuaki Matsumoto
  • Patent number: 8956762
    Abstract: In a lithium ion secondary battery including a positive electrode, a separator, a negative electrode, and a package body, the negative electrode includes simple substance silicon as a negative electrode active material, and a negative electrode binder, and is doped with lithium, and the following formulas (1) and (2) are satisfied: 1.2?Ma/Mc?1.9??(1) 1.0<Ma/(Mc+MLi)<1.6??(2) wherein an amount of lithium inserted into the negative electrode until the negative electrode reaches a potential of 0.02 V with respect to metal lithium is Ma (a number of atoms), an amount of lithium released from the positive electrode until the positive electrode reaches a potential of 4.3 V with respect to metal lithium is Mc (a number of atoms), and an amount of lithium with which the negative electrode is doped is MLi (a number of atoms).
    Type: Grant
    Filed: July 29, 2011
    Date of Patent: February 17, 2015
    Assignees: NEC Corporation, NEC Energy Devices, Ltd.
    Inventors: Ryuichi Kasahara, Jiro Iriyama, Tetsuya Kajita, Hiroo Takahashi, Tatsuji Numata, Daisuke Kawasaki
  • Publication number: 20140377635
    Abstract: The present invention provides an electrolyte solution for a lithium ion secondary battery comprising 65 to 99% by volume of a phosphate ester compound, 0.01 to 30% by volume of a fluorinated carbonate compound, and 0.1 to 10% by volume of a halogenated phosphate ester compound and/or 0.1 to 30% by volume of a solvent having a specific dielectric constant of 15 or more, and a lithium ion secondary battery having the same.
    Type: Application
    Filed: February 25, 2013
    Publication date: December 25, 2014
    Applicant: NEC Corporation
    Inventors: Kazuaki Matsumoto, Kazuhiko Inoue, Daisuke Kawasaki
  • Publication number: 20140076729
    Abstract: The object of an exemplary embodiment of the invention is to provide a negative electrode having excellent cycle property. An exemplary embodiment of the invention a method for doping and dedoping lithium for the first time after a negative electrode for a lithium secondary battery comprising silicon oxide as an active material is produced, comprising doping the lithium within the following current value range (A) and within the following doped amount range (B); current value range (A): a range of a current value in which a doped amount in which only one peak appears at 1 V or less on the V-dQ/dV curve becomes maximum, wherein the V-dQ/dV curve represents a relationship between voltage V of the negative electrode with respect to a lithium reference electrode and dQ/dV that is a ratio of variation dQ of lithium dedoped amount Q in the negative electrode to variation dV of the voltage V, and doped amount range (B): a range of a doped amount in which only one peak appears at 1 V or less on the V-dQ/dV curve.
    Type: Application
    Filed: April 6, 2012
    Publication date: March 20, 2014
    Inventors: Jiro Iriyama, Tetsuya Kajita, Daisuke Kawasaki, Tatsuji Numata
  • Publication number: 20140045063
    Abstract: Provided is a negative electrode active material for a lithium secondary cell, the material having the function of a binder for the active material, and being capable of stable reversible reactions with lithium. Also, provided are an extended-life lithium secondary cell having improved energy density and stable charge/discharge, and a method for producing the same. The negative electrode active material for a lithium secondary cell is polyimide represented by formula (1) (wherein R1 and R2 independently denote an alkyl, alkoxy, acyl, phenyl, or phenoxy group).
    Type: Application
    Filed: April 27, 2012
    Publication date: February 13, 2014
    Inventors: Jiro Iriyama, Tetsuya Kajita, Daisuke Kawasaki, Tatsuji Numata, Kazuhiko Inoue