Patents by Inventor Yutaka Nakazawa
Yutaka Nakazawa 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).
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Patent number: 7092239Abstract: An electric double layer capacitor comprises: a separator; a pair of electrodes separated by the separator, and the electrodes including activated carbon particles and a binder binding the activated carbon particles; and a pair of collectors separated by the pair of electrodes, wherein a density of the electrodes is in the range of 1.4 g/cm3 to 1.8 g/cm3.Type: GrantFiled: February 6, 2002Date of Patent: August 15, 2006Assignee: NEC Tokin CorporationInventors: Yutaka Nakazawa, Koji Sakata, Ryuuichi Kasahara
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Patent number: 6870725Abstract: An electric double layer capacitor, including at least one basic cell, an electrode plate, and an outer package which covers the basic cell and the electrode plate in a decompression state. The basic cell may be laminated in its thickness direction to form a layered cell and includes a separator, a pair of polarized electrodes disposed so as to sandwich the separator, a pair of collectors disposed so as to sandwich the polarized electrodes, and a gasket disposed between the pair of collectors so as to surround the pair of polarized electrodes. The electrode plate body is attached to each of the collectors located at the outermost side in a laminated direction of the layered cell. A sealing material having a higher gas barrier property than the collectors is disposed so as to seal an interface between the collectors and the electrode plate in the outer package.Type: GrantFiled: July 7, 2003Date of Patent: March 22, 2005Assignee: NEC Tokin CorporationInventors: Koji Sakata, Kazuya Mimura, Yutaka Nakazawa, Satoshi Abe
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Patent number: 6843810Abstract: 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: GrantFiled: January 2, 2004Date of Patent: January 18, 2005Assignee: NEC Tokin CorporationInventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
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Publication number: 20040141280Abstract: 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: ApplicationFiled: January 2, 2004Publication date: July 22, 2004Applicant: NEC TOKIN CORPORATIONInventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
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Patent number: 6751084Abstract: 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: GrantFiled: October 17, 2002Date of Patent: June 15, 2004Assignee: NEC Tokin CorporationInventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
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Patent number: 6741450Abstract: 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: GrantFiled: December 17, 2002Date of Patent: May 25, 2004Assignee: NEC Tokin CorporationInventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
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Publication number: 20040066604Abstract: An electric double layer capacitor, including at least one basic cell, an electrode plate, and an outer package which covers the basic cell and the electrode plate in a decompression state. The basic cell may be laminated in its thickness direction to form a layered cell and includes a separator, a pair of polarized electrodes disposed so as to sandwich the separator, a pair of collectors disposed so as to sandwich the polarized electrodes, and a gasket disposed between the pair of collectors so as to surround the pair of polarized electrodes. The electrode plate body is attached to each of the collectors located at the outermost side in a laminated direction of the layered cell. A sealing material having a higher gas barrier property than the collectors is disposed so as to seal an interface between the collectors and the electrode plate in the outer package.Type: ApplicationFiled: July 7, 2003Publication date: April 8, 2004Applicant: NEC TOKIN CORPORATIONInventors: Koji Sakata, Kazuya Mimura, Yutaka Nakazawa, Satoshi Abe
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Patent number: 6717795Abstract: 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: GrantFiled: October 31, 2002Date of Patent: April 6, 2004Assignee: NEC Tokin CorporationInventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
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Patent number: 6671165Abstract: A separator, a pair of polarized electrodes, gaskets holding the separator and the polarized electrodes from their sides, and a pair of the collectors provided in contact with the outer surfaces of polarized electrodes and gaskets are provided in an electric double layer capacitor. The collectors are a lamination having a conductive film formed by coating a conductive resin solution containing a conductive material to at least one surface of copper foil.Type: GrantFiled: August 31, 2000Date of Patent: December 30, 2003Assignee: NEC Tokin CorporationInventors: Yutaka Nakazawa, Koji Sakata, Kazuya Mimura, Takashi Yasuda
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Patent number: 6657850Abstract: An electrical double layer capacitor includes a capacitor cell structure comprising: a separator; polarization electrodes; collectors; and a gasket, wherein at least a part of at least either one of the collectors and the gasket has a gas permeability coefficient of at least 4.0E-12[m3/(m2·S·Pa)].Type: GrantFiled: March 19, 2002Date of Patent: December 2, 2003Assignee: NEC Tokin CorporationInventors: Yutaka Nakazawa, Koji Sakata, Ryuuichi Kasahara
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Patent number: 6636417Abstract: An electric double layer capacitor, including at least one basic cell, an electrode plate, and an outer package which covers the basic cell and the electrode plate in a decompression state. The basic cell may be laminated in its thickness direction to form a layered cell and includes a separator, a pair of polarized electrodes disposed so as to sandwich the separator, a pair of collectors disposed so as to sandwich the polarized electrodes, and a gasket disposed between the pair of collectors so as to surround the pair of polarized electrodes. The electrode plate body is attached to each of the collectors located at the outermost side in a laminated direction of the layered cell. A sealing material having a higher gas barrier property than the collectors is disposed so as to seal an interface between the collectors and the electrode plate in the outer package.Type: GrantFiled: May 23, 2001Date of Patent: October 21, 2003Assignee: NEC Tokin CorporationInventors: Koji Sakata, Kazuya Mimura, Yutaka Nakazawa, Satoshi Abe
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Patent number: 6625007Abstract: 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: GrantFiled: March 14, 2002Date of Patent: September 23, 2003Assignee: NEC Tokin CorporationInventors: Koji Sakata, Yutaka Nakazawa, Ryuichi Kasahara
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Publication number: 20030147201Abstract: 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: ApplicationFiled: December 17, 2002Publication date: August 7, 2003Applicant: NEC TOKIN CORPORATIONInventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
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Publication number: 20030095372Abstract: 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: ApplicationFiled: October 31, 2002Publication date: May 22, 2003Applicant: NEC TOKIN CORPORATIONInventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
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Publication number: 20030081372Abstract: 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: ApplicationFiled: October 17, 2002Publication date: May 1, 2003Applicant: NEC TOKIN CORPORATIONInventors: Yutaka Nakazawa, Ryuichi Kasahara, Koji Sakata
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Publication number: 20020191369Abstract: An electrical double layer capacitor includes a capacitor cell structure comprising: a separator; polarization electrodes; collectors; and a gasket, wherein at least a part of at least either one of the collectors and the gasket has a gas permeability coefficient of at least 4.0E-12[m3/(m2·S·Pa)].Type: ApplicationFiled: March 19, 2002Publication date: December 19, 2002Applicant: NEC CORPORATIONInventors: Yutaka Nakazawa, Koji Sakata, Ryuuichi Kasahara
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Publication number: 20020154467Abstract: An electric double layer capacitor comprises: a separator; a pair of electrodes separated by the separator, and the electrodes including activated carbon particles and a binder binding the activated carbon particles; and a pair of collectors separated by the pair of electrodes, wherein a density of the electrodes is in the range of 1.4 g/cm3 to 1.8 g/cm3.Type: ApplicationFiled: February 6, 2002Publication date: October 24, 2002Applicant: NEC CORPORATIONInventors: Yutaka Nakazawa, Koji Sakata, Ryuuichi Kasahara
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Publication number: 20020131232Abstract: 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: ApplicationFiled: March 14, 2002Publication date: September 19, 2002Applicant: NEC CORPORATIONInventors: Koji Sakata, Yutaka Nakazawa, Ryuichi Kasahara
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Patent number: 6392868Abstract: An electric double-layer capacitor has a pair of thrust plates for thrusting a stacked cell pair and a gasket for encapsulating the stacked cell pair together with the thrust plates. The thrust plate has slanted side surfaces for effecting a close contact with a packaging overcoat. The thrust plates and the mounting gasket are coupled together by an interdigitaion relationship.Type: GrantFiled: February 26, 2001Date of Patent: May 21, 2002Assignee: NEC CorporationInventors: Masako Ohya, Kazuya Mimura, Yutaka Nakazawa, Satoshi Abe, Satoshi Arai, Takashi Yasuda, Toshihisa Nagasawa, Koji Sakata, Mitsuru Ogawa
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Patent number: 6341058Abstract: The present invention provides an electric double layer capacitor having a pail of polarized electrodes separated by a separator, the polarized electrodes having surfaces facing to the separator, wherein substantially entire parts of the surfaces of the polarized electrodes are spaced from the separator to form inner spaces between the polarized electrodes and the separator.Type: GrantFiled: March 30, 2000Date of Patent: January 22, 2002Assignee: NEC CorporationInventors: Koji Sakata, Kazuya Mimura, Yutaka Nakazawa