Patents by Inventor Ryuichi Kasahara

Ryuichi Kasahara 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).

  • Publication number: 20110274966
    Abstract: An exemplary embodiment of the invention provides a nonaqueous electrolytic solution secondary battery in which capacity deterioration associated with a charge/discharge cycle at a high temperature (45° C. or higher) can be prevented. An exemplary embodiment of the invention is a nonaqueous electrolytic solution secondary battery, comprising an electrode element in which a cathode and an anode are stacked, a nonaqueous electrolytic solution which contains at least one of carbonate solvent, and a gel in an outer packaging body; wherein the anode comprises a silicon oxide represented by SiOx (0<x?2) as an anode active material, and the gel comprises a cross-linked unsaturated carboxylate ester polymer and a carbonate solvent which is the same as at least one of the carbonate solvent contained in the nonaqueous electrolytic solution.
    Type: Application
    Filed: January 19, 2010
    Publication date: November 10, 2011
    Inventors: Jiro Iriyama, Tatsuji Numata, Ryuichi Kasahara, Tetsuya Kajita
  • Publication number: 20110244328
    Abstract: There is provided a negative electrode for a nonaqueous electrolyte secondary battery in which when a battery is formed, the energy density is high, and moreover, the decrease in charge and discharge capacity is small even if charge and discharge are repeated. By using silicon oxide particles having a particle diameter in a particular range as a starting raw material, and heating these particles in the range of 850° C. to 1050° C., Si microcrystals are deposited on the surfaces of the particles. Then, by performing doping of Li, a structure comprising a plurality of protrusions having height and cross-sectional area in a particular range is formed on the surfaces. The average value of the height of the above protrusions is 2% to 19% of the average particle diameter of the above lithium-containing silicon oxide particles.
    Type: Application
    Filed: December 17, 2009
    Publication date: October 6, 2011
    Applicant: NEC ENERGY DEVICES, LTD.
    Inventors: Jiro Iriyama, Ryuichi Kasahara, Tetsuya Kajita, Tatsuji Numata
  • Publication number: 20110197435
    Abstract: The present invention provides a stack-type lithium-ion polymer battery wherein: the battery capacity is not being degraded; the generation of the wrinkles and fracture of the separator is being suppressed; the battery has gas releasing paths; the displacement of an electrode stack hardly occurs; and the workability at the time of placing the electrode stack in a package body is improved by fixing the electrode stack. A stack-type lithium-ion polymer battery of the present invention comprises: a cathode 13; an anode 14; a separator 15; and a gel electrolyte; wherein an electrode stack 23 in which the cathode 13 and the anode 14 are stacked through the separator 15 is enclosed and fixed by insulating porous sheets 21 and 24, and is packaged with a laminate material.
    Type: Application
    Filed: April 26, 2011
    Publication date: August 18, 2011
    Applicant: NEC TOKIN CORPORATION
    Inventors: Shinako KANEKO, Ryuichi KASAHARA, Hiroshi KOBAYASHI, Yasutaka KONO, Toshihiko NISHIYAMA
  • Publication number: 20100173201
    Abstract: An objective of the present invention is to provide a lithium secondary battery which can achieve a higher capacity and a longer life without reduction in a lower voltage in the battery. In the present invention, a compound represented by general formula (I) described below is used as a cathode active material, and a compound represented by general formula (II) described below is used as an anode active material; Lia1(Nix1Mn2-x1-y1M1y1)O4??(I) wherein the M1 is at least one of Ti, Si, Mg and Al, the a1 satisfies 0?a1?1, the x1 satisfies 0.4?x1?0.6, and the y1 satisfies 0?y1?0.4; and Lia2M21-y2M3y2Oz2??(II) wherein the M2 is at least one of Si and Sn; the M3 is at least one of Fe, Ni and Cu, the a2 satisfies 0?a2?5, the y2 satisfies 0?y2<0.3, and the z2 satisfies 0<z2<2.
    Type: Application
    Filed: March 17, 2010
    Publication date: July 8, 2010
    Applicant: NEC TOKIN CORPORATION
    Inventors: Takehiro NOGUCHI, Masaaki MATSUU, Ryuichi KASAHARA, Tatsuji NUMATA, Yutaka BANNAI
  • Publication number: 20100173200
    Abstract: An objective of the present invention is to provide a lithium secondary battery which can achieve a higher capacity and a longer life without reduction in a lower voltage in the battery. In the present invention, a compound represented by general formula (I) described below is used as a cathode active material, and a compound represented by general formula (II) described below is used as an anode active material; Lia1(Nix1Mn2-x1-y1M1y1)O4??(I) wherein the M1 is at least one of Ti, Si, Mg and Al, the a1 satisfies 0?a1?1, the x1 satisfies 0.4?x1?0.6, and the y1 satisfies 0?y1?0.4; and Lia2M21-y2M3y2Oz2??(II) wherein the M2 is at least one of Si and Sn; the M3 is at least one of Fe, Ni and Cu, the a2 satisfies 0?a2?5, the y2 satisfies 0?y2?0.3, and the z2 satisfies 0?z2?2.
    Type: Application
    Filed: March 17, 2010
    Publication date: July 8, 2010
    Applicant: NEC TOKIN CORPORATION
    Inventors: Takehiro NOGUCHI, Masaaki MATSUU, Ryuichi KASAHARA, Tatsuji NUMATA, Yutaka BANNAI
  • Publication number: 20070248885
    Abstract: The invention provides a lithium ion secondary battery comprising a positive electrode, a negative electrode and an electrolysis solution containing an aprotic solvent having an electrolyte dissolved in it, wherein the negative electrodes uses an amorphous carbon material as a negative electrode active material. The amorphous carbon material has (A) an average particle diameter (median size of 7 ?m to 20 ?m inclusive as measured by a laser diffraction scattering method and (B) a particle size distribution as measured by a laser diffraction scattering method, in which distribution the ratio of particles of less than 3 ?m in diameter is 1% by mass to 10% mass inclusive, and is free of an electrical conducting material.
    Type: Application
    Filed: April 19, 2007
    Publication date: October 25, 2007
    Applicant: NEC TOKIN Corporation
    Inventors: Yutaka Bannai, Tatsuji Numata, Ryuichi Kasahara
  • Publication number: 20070172734
    Abstract: An objective of the present invention is to provide a lithium secondary battery which can achieve a higher capacity and a longer life without reduction in a lower voltage in the battery. In the present invention, a compound represented by general formula (I) described below is used as a cathode active material, and a compound represented by general formula (II) described below is used as an anode active material; Lia1(Nix1Mn2-x1-y1M1y1)O4??(I) wherein the M1 is at least one of Ti, Si, Mg and Al, the a1 satisfies 0<a1<, the x1 satisfies 0.4?x1?0.6, and the y1 satisfies 0?y1?0.4; and Lia2M21-y2M3y2Oz2??(II) wherein the M2 is at least one of Si and Sn; the M3 is at least one of Fe, Ni and Cu, the a2 satisfies 0?a2?5, the y2 satisfies 0?y2<0.3, and the z2 satisfies 0<z2<2.
    Type: Application
    Filed: January 24, 2007
    Publication date: July 26, 2007
    Inventors: Takehiro NOGUCHI, Masaaki MATSUU, Ryuichi KASAHARA, Tatsuji NUMATA, Yutaka BANNAI
  • Publication number: 20070117008
    Abstract: The present invention provides a stack-type lithium-ion polymer battery wherein: the battery capacity is not being degraded; the generation of the wrinkles and fracture of the separator is being suppressed; the battery has gas releasing paths; the displacement of an electrode stack hardly occurs; and the workability at the time of placing the electrode stack in a package body is improved by fixing the electrode stack. A stack-type lithium-ion polymer battery of the present invention comprises: a cathode 13; an anode 14; a separator 15; and a gel electrolyte; wherein an electrode stack 23 in which the cathode 13 and the anode 14 are stacked through the separator 15 is enclosed and fixed by insulating porous sheets 21 and 24, and is packaged with a laminate material.
    Type: Application
    Filed: November 20, 2006
    Publication date: May 24, 2007
    Inventors: Shinako KANEKO, Ryuichi KASAHARA, Hiroshi KOBAYASHI, Yasutaka KONO, Toshihiko NISHIYAMA
  • Patent number: 6843810
    Abstract: An electric double layer capacitor is disclosed which is capable of preventing transmission of an electrolytic solution vaporized in a basic cell through current collectors and capable of improving a yield. A method for preparing the electric double layer capacitor is also disclosed.
    Type: Grant
    Filed: January 2, 2004
    Date of Patent: January 18, 2005
    Assignee: NEC Tokin Corporation
    Inventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
  • Publication number: 20040233613
    Abstract: In an electric double layer capacitor having a pair of collectors, a pair of polarizing electrodes interposed between the collectors and faced each other with a separator interposed between the polarizing electrodes, each collector has a metallic foil and a conductive polymer layer located between the metallic foil and the polarizing electrode. The conductive polymer layer is formed by conductive polymer identical with that of the polarizing electrode.
    Type: Application
    Filed: May 13, 2004
    Publication date: November 25, 2004
    Applicant: NEC TOKIN Corporation
    Inventors: Ryuichi Kasahara, Masako Ohya, Makoto Unno
  • Publication number: 20040141280
    Abstract: An electric double layer capacitor is disclosed which is capable of preventing transmission of an electrolytic solution vaporized in a basic cell through current collectors and capable of improving a yield. A method for preparing the electric double layer capacitor is also disclosed.
    Type: Application
    Filed: January 2, 2004
    Publication date: July 22, 2004
    Applicant: NEC TOKIN CORPORATION
    Inventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
  • Patent number: 6751084
    Abstract: An electric double layer capacitor is disclosed which is capable of preventing transmission of an electrolytic solution vaporized in a basic cell through current collectors and capable of improving a yield. A method for preparing the electric double layer capacitor is also disclosed.
    Type: Grant
    Filed: October 17, 2002
    Date of Patent: June 15, 2004
    Assignee: NEC Tokin Corporation
    Inventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
  • Patent number: 6741450
    Abstract: An electric double-layer capacitor includes a cell structure formed by laminating basic cells in series one on another. Each of the basic cells includes a pair of collectors, a separator disposed between said collectors, gaskets disposed at peripheral edges of said pair of collectors and said separator to define a pair of closed spaces, and a pair of polarizable electrodes which are disposed in said closed spaces defined by said collectors, said separator and said gaskets, respectively and which contain an electrolytic solution. The basic cells are laminated one on another with a back of each of said collectors opposed to said polarizable electrode serving as a connection surface. The electric double-layer capacitor further includes a lead terminal/electrode plate assembly having electrode plates bonded to the collectors located at opposite ends of the cell structure through conductive bond layers.
    Type: Grant
    Filed: December 17, 2002
    Date of Patent: May 25, 2004
    Assignee: NEC Tokin Corporation
    Inventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
  • Patent number: 6717795
    Abstract: An electric double-layer capacitor includes a cell structure constituted by laminating basic cells in series with their collectors serving as connections. Each of the basic cells includes a pair of collectors, a separator disposed between the collectors, and a pair of polarizable electrodes which are disposed between the collectors and the separator and in which an electrolytic solution is contained. The capacitor further includes lead terminal/electrode plate assemblies each having an electrode plate electrically connected to the collectors at opposite ends of the cell structure. Each of the collectors includes a matrix made of an elastomer having a hardness Hs in a range of about 55 (inclusive) to lower than about 85 at ambient temperature, and conductive particles dispersed in the matrix. Thus, in the electric double-layer capacitor, a lower ESR can be realized at in initial stage and even after the service for a long period.
    Type: Grant
    Filed: October 31, 2002
    Date of Patent: April 6, 2004
    Assignee: NEC Tokin Corporation
    Inventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
  • Patent number: 6625007
    Abstract: A component cell of an electric double layer capacitor is fabricated by forming first and second half portions of the cell. In each of the half portions a polarized electrode impregnated with electrolyte is pasted to a collector electrode so that a stepped portion is formed on the periphery of the collector electrode. A gasket is attached to the stepped portion of each half portion, and a center gasket is attached to the periphery of a separator which is placed between the first and second half portions. Pressure is then applied to the first and second half portions of the cell in directions towards each other at an elevated temperature so that all gaskets are thermally joined together. A plurality of such component cells are stacked in a layered structure and sealed in a package.
    Type: Grant
    Filed: March 14, 2002
    Date of Patent: September 23, 2003
    Assignee: NEC Tokin Corporation
    Inventors: Koji Sakata, Yutaka Nakazawa, Ryuichi Kasahara
  • Publication number: 20030147201
    Abstract: An electric double-layer capacitor includes a cell structure formed by laminating basic cells in series one on another. Each of the basic cells includes a pair of collectors, a separator disposed between said collectors, gaskets disposed at peripheral edges of said pair of collectors and said separator to define a pair of closed spaces, and a pair of polarizable electrodes which are disposed in said closed spaces defined by said collectors, said separator and said gaskets, respectively and which contain an electrolytic solution. The basic cells are laminated one on another with a back of each of said collectors opposed to said polarizable electrode serving as a connection surface. The electric double-layer capacitor further includes a lead terminal/electrode plate assembly having electrode plates bonded to the collectors located at opposite ends of the cell structure through conductive bond layers.
    Type: Application
    Filed: December 17, 2002
    Publication date: August 7, 2003
    Applicant: NEC TOKIN CORPORATION
    Inventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
  • Publication number: 20030095372
    Abstract: An electric double-layer capacitor includes a cell structure constituted by laminating basic cells in series with their collectors serving as connections. Each of the basic cells includes a pair of collectors, a separator disposed between the collectors, and a pair of polarizable electrodes which are disposed between the collectors and the separator and in which an electrolytic solution is contained. The capacitor further includes lead terminal/electrode plate assemblies each having an electrode plate electrically connected to the collectors at opposite ends of the cell structure. Each of the collectors includes a matrix made of an elastomer having a hardness Hs in a range of about 55 (inclusive) to lower than about 85 at ambient temperature, and conductive particles dispersed in the matrix. Thus, in the electric double-layer capacitor, a lower ESR can be realized at in initial stage and even after the service for a long period.
    Type: Application
    Filed: October 31, 2002
    Publication date: May 22, 2003
    Applicant: NEC TOKIN CORPORATION
    Inventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
  • Publication number: 20030081372
    Abstract: An electric double layer capacitor is disclosed which is capable of preventing transmission of an electrolytic solution vaporized in a basic cell through current collectors and capable of improving a yield. A method for preparing the electric double layer capacitor is also disclosed.
    Type: Application
    Filed: October 17, 2002
    Publication date: May 1, 2003
    Applicant: NEC TOKIN CORPORATION
    Inventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
  • Patent number: 6507479
    Abstract: An electric double-layer capacitor (EDLC) has a laminated overcoat encapsulating a stacked body including a plurality of basic cells and a pair of terminals sandwiching therebetween the stacked body. The innermost film of the laminated overcoat is thermally fused onto the exposed surfaces of the terminal plates and the stacked body substantially without a gap. The fusing step is conducted by an equal-pressure pressing using a hot water while the internal of the laminated overcoat is evacuated.
    Type: Grant
    Filed: January 31, 2001
    Date of Patent: January 14, 2003
    Assignee: NEC Corporation
    Inventors: Takashi Saito, Ryuichi Kasahara
  • Publication number: 20020131232
    Abstract: A component cell of an electric double layer capacitor is fabricated by forming first and second half portions of the cell. In each of the half portions a polarized electrode impregnated with electrolyte is pasted to a collector electrode so that a stepped portion is formed on the periphery of the collector electrode. A gasket is attached to the stepped portion of each half portion, and a center gasket is attached to the periphery of a separator which is placed between the first and second half portions. Pressure is then applied to the first and second half portions of the cell in directions towards each other at an elevated temperature so that all gaskets are thermally joined together. A plurality of such component cells are stacked in a layered structure and sealed in a package.
    Type: Application
    Filed: March 14, 2002
    Publication date: September 19, 2002
    Applicant: NEC CORPORATION
    Inventors: Koji Sakata, Yutaka Nakazawa, Ryuichi Kasahara