Patents by Inventor Shinako Okada

Shinako Okada 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: 20040110062
    Abstract: The present invention provides a conductive polymer comprising a polybiphenylaniline which is doped with dopant comprising at least an acid having a single site of a group which dissociates proton.
    Type: Application
    Filed: November 20, 2003
    Publication date: June 10, 2004
    Applicant: NEC TOKIN CORPORATION
    Inventors: Gaku Harada, Toshihiko Nishiyama, Masaki Fujiwara, Shinako Okada, Masato Kurosaki
  • Patent number: 6686089
    Abstract: A battery electrode is obtained by coating an electrically conductive film serving as a collector with an aqueous solution of formic acid containing polypyridine, which is an active material, in dissolved form as well as carbon powder serving as a conduction aid, and drying the solution on the film. A secondary battery is manufactured using such electrodes.
    Type: Grant
    Filed: August 27, 1999
    Date of Patent: February 3, 2004
    Assignee: NEC Tokin Corporation
    Inventors: Masaki Fujiwara, Gaku Harada, Shinako Okada, Toshihiko Nishiyama
  • Patent number: 6428928
    Abstract: The present invention provides an electrode containing a quinoxaline resin and an electrolyte which includes at least one of sulfuric acid ions and sulfonic acid ions, or the electrolyte which includes cations having ion radius of not more than 3 angstroms.
    Type: Grant
    Filed: March 8, 2000
    Date of Patent: August 6, 2002
    Assignee: NEC Corporation
    Inventors: Gaku Harada, Toshihiko Nishiyama, Masaki Fujiwara, Shinako Okada, Masato Kurosaki
  • Patent number: 6413675
    Abstract: A multi layer electrolyte and a secondary cell using the multi layer electrolyte. The multi layer electrolyte comprises a solid electrolyte and other electrolyte such as gel electrolyte and/or electrolytic solution layer laminated on the solid electrolyte. The secondary cell using the multi layer electrolyte includes at least a positive electrode, a negative electrode and the multi layer electrolyte which comprises: a solid electrolyte layer; and at least one electrolyte layers selected from a gel electrolyte layer and an electrolytic solution layer and laminated on the solid electrolyte layer. By this structure, it is possible to use active material dissoluble in electrolytic solution as electrode active material and to realize a cell which can be quickly charged and discharged and which has superior capacity appearance rate and superior charge-discharge cycle characteristics.
    Type: Grant
    Filed: July 15, 1999
    Date of Patent: July 2, 2002
    Assignee: NEC Corporation
    Inventors: Gaku Harada, Toshihiko Nishiyama, Masaki Fujiwara, Shinako Okada
  • Patent number: 6343003
    Abstract: A capacitor element and a battery cell which a dry-up phenomenon is restricted and an internal resistance is small are provided. The capacitor element provides a porous separator which has ion permeability and the ability of insulation, a pair of carbon electrode layers having many successive through holes separated by the porous separator, a non-conductive gasket holding the surrounding ends of the carbon electrode layers, a pair of conductive separators holding the carbon electrode layers and the non-conductive gasket from the outside, electrolyte solution in the successive through holes of the carbon electrode layers, and minute particles which are more than 0.1 weight % and less than 5.0 weight % of the electrolyte solution. A battery cell provides electrolyte solution and positive/negative electrode active material layers containing minute particles which are more than 0.1 weight % and less than 5.0 weight % of the electrolyte solution in the successive through holes.
    Type: Grant
    Filed: November 9, 1998
    Date of Patent: January 29, 2002
    Assignee: NEC Corporation
    Inventors: Koji Sakata, Shinako Okada, Junko Kurihara, Gaku Harada
  • Patent number: 6300015
    Abstract: The present invention provides a positive electrode active material doped with a dopant comprising an anion having the same or similar molecular structure to a polymer matrix of at least one of a solid electrolyte and a gel solid electrolyte.
    Type: Grant
    Filed: April 5, 1999
    Date of Patent: October 9, 2001
    Assignee: NEC Corporation
    Inventors: Toshihiko Nishiyama, Gaku Harada, Shinako Okada, Masaki Fuziwara
  • Patent number: 6277518
    Abstract: A polymer composed of structural units having a fused ring structure derived from a nitrogen-containing cyclic compound and a quinone compound as represented by the following formula is used as an electrode material for use in batteries. This makes it possible to provide batteries having excellent cycle characteristics and a high power density.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: August 21, 2001
    Assignee: NEC Corporation
    Inventors: Katsuhiko Naoi, Shunzou Suematsu, Ari Manago, Junko Kurihara, Toshihiko Nishiyama, Gaku Harada, Shinako Okada, Koji Sakata
  • Patent number: 6274268
    Abstract: A polymer secondary battery uses, for at least one of the active material of positive electrode and the active material of negative electrode, a polymer-carbon composite material including powdered carbon having its surfaces coated with an organic compound polymer capable of adsorbing and desorbing protons electrochemically. The polymer secondary battery has a high rate of appearance of capacity and excellent cycle characteristics.
    Type: Grant
    Filed: July 7, 1999
    Date of Patent: August 14, 2001
    Assignee: NEC Corporation
    Inventors: Masaki Fujiwara, Gaku Harada, Shinako Okada, Toshihiko Nishiyama
  • Patent number: 6254761
    Abstract: A method of producing a conductive polymer comprises the following steps of depositing a solid-state organic compound and contacting a collector with an electrolytic solution thereby to cause an electrolytic polymerization of said organic compound.
    Type: Grant
    Filed: March 20, 2000
    Date of Patent: July 3, 2001
    Assignee: NEC Corporation
    Inventors: Shinako Okada, Toshihiko Nishiyama, Masaki Fujiwara, Gaku Harada, Masato Kurosaki
  • Patent number: 6248474
    Abstract: An electrode for a secondary or rechargeable battery using a conducting polymer as an active material is provided, which realizes a large capacity, a good cycling property, and a high power density. This electrode is comprised of an active material layer having an active material made of a mixture of a nitrogen-containing compound polymer and a quinone-system compound. The molar ratio of the nitrogen-containing compound polymer and the quinone-system compound is preferably in the range of 0.25:0.75˜0.75:0.25 and is more preferably in the range of 0.33:0.66˜0.66:0.33. The active material of the electrode is produced by using a mixture of powders of the nitrogen-containing compound polymer and the quinone-system compound.
    Type: Grant
    Filed: November 4, 1998
    Date of Patent: June 19, 2001
    Assignee: NEC Corporation
    Inventors: Toshihiko Nishiyama, Junko Kurihara, Gaku Harada, Koji Sakata, Shinako Okada
  • Patent number: 6099989
    Abstract: The present invention provides a polymer secondary battery comprising a pair of current collectors and electrodes arranged in opposed relationship with an electrolyte solution-containing separator or a solid electrolyte interposed therebetween, the polymer secondary battery having a structure in which a first polymer active material layer adjacent to the current collector of the negative electrode has laminated thereto at least one layer of a polymer material having an oxidation-reduction potential higher than that of the first polymer active material layer. This polymer secondary battery has a high rate of appearance of capacity, is capable of quick charging and discharging, and exhibits excellent cycle characteristics.
    Type: Grant
    Filed: October 19, 1998
    Date of Patent: August 8, 2000
    Assignee: NEC Corporation
    Inventors: Gaku Harada, Koji Sakata, Junko Kurihara, Shinako Okada