Patents by Inventor Hiroto Sagisaka

Hiroto Sagisaka 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: 7608366
    Abstract: A nonaqueous electrolyte secondary battery having a positive electrode made of a carbonaceous material, an electrolyte containing a lithium salt, and a negative electrode made of metallic lithium or a material capable of occluding and releasing lithium, wherein said positive electrode is formed from a boronized graphitic material containing boron or a boron compound such that the content of boron therein is 0.05-11 wt %. A method for production of the positive electrode of the nonaqueous electrolyte secondary battery.
    Type: Grant
    Filed: September 6, 2006
    Date of Patent: October 27, 2009
    Assignee: FDK Corporation
    Inventors: Takashi Suzuki, Masanori Nakanishi, Yoshiro Harada, Hiroto Sagisaka
  • Patent number: 7452633
    Abstract: A non-aqueous electrolyte secondary battery in which a positive electrode formed of a graphite powder and an negative electrode formed of a material capable of absorption/desorption of a lithium metal or lithium are placed to face each other in an electrolyte containing lithium salt. The positive electrode of this battery where a Lc (112) which is the size of crystallite in a c axis direction which is calculated from a (112) diffraction line of a graphite crystal and determined by a powder X-ray diffraction method which is from 4 nm to 30 nm, and a charge capacity at the first cycle which is calculated on the basis of a total weight of the graphite material of the positive electrode filled in the battery is 20 to 50 (mAh/g). Preferably, the graphite powder of the positive electrode has an ratio (A/B) which is the ratio of a specific surface area A determined by a nitrogen absorption (BET) method to a surface area B determined on the basis of an area average diameter of 20 or less.
    Type: Grant
    Filed: April 11, 2005
    Date of Patent: November 18, 2008
    Assignee: FDK Corporation
    Inventors: Takashi Suzuki, Toshiyuki Miwa, Hiroto Sagisaka, Kenji Nabekura, Masanori Nakanishi, Minoru Inagaki
  • Patent number: 7344803
    Abstract: An alkaline primary cell which is improved in reduction of self-discharge and cell capacity under storage at a high temperature, has a prolonged life and makes use of nickel oxyhydroxide is provided inexpensively. ?-Form nickel oxyhydroxide is contained in a positive electrode mixture as an active material, which contains cobalt and zinc as a substitutional element for solid solution, and has a total amount X+Y of molar ratios of cobalt atom X and zinc atom Y such that 2?X+Y?16, with a mixing ratio satisfying the relationship of Y?3/2×X+1/2 and Y?2/3×X ?1/3, and where a diffraction peak obtained as a result of measurement of X-ray powder diffraction of nickel oxyhydroxide appears only in the vicinity of 18.5° within a range of 2?=10°-30°.
    Type: Grant
    Filed: February 26, 2002
    Date of Patent: March 18, 2008
    Assignees: FDK Corporation, Tanaka Chemical Corporation
    Inventors: Shinichi Ueki, Yoshiro Harada, Mitsuhiro Nakamura, Hiroto Sagisaka, Takeshi Miyazaki
  • Patent number: 7238449
    Abstract: A nonaqueous electrolyte secondary battery having a positive electrode made of a carbonaceous material, an electrolyte containing a lithium salt, and a negative electrode made of metallic lithium or a material capable of occluding and releasing lithium, wherein said positive electrode is formed from a boronized graphitic material containing boron or a boron compound such that the content of boron therein is 0.05-11 wt %. A method for production of the positive electrode of the nonaqueous electrolyte secondary battery.
    Type: Grant
    Filed: November 14, 2003
    Date of Patent: July 3, 2007
    Assignee: FDK Corporation
    Inventors: Takashi Suzuki, Masanori Nakanishi, Yoshiro Harada, Hiroto Sagisaka
  • Publication number: 20070148548
    Abstract: A non-aqueous electrolyte secondary battery includes a positive electrode 11 made of graphite powder and a negative electrode 13 made of lithium metal or a lithium-intercalatable/deintercalatable material. The positive electrode 11 and the negative electrode 13 are faced to each other with an electrolyte, containing a lithium salt, interposed in between. The positive electrode 11 has a carbon-derived absorption peak which appears within a range of 3200 gauss to 3400 gauss in an electron spin resonance method in which measurement is performed using an X band. A relative ratio (?H40K/?H296K) of the full width of half maximum intensity ?H40K of the peak measured at a temperature of 40 K to the full width of half maximum intensity ?H296K of the peak measured at a temperature of 296 K is 2.1 or more. Accordingly, it is possible to provide the non-aqueous electrolyte secondary battery which prevents degradation of the capacity in charge/discharge cycles after performing high temperature floating charge.
    Type: Application
    Filed: January 2, 2007
    Publication date: June 28, 2007
    Applicant: FDK CORPORATION
    Inventors: Takashi Suzuki, Toshiyuki Miwa, Hiroto Sagisaka, Yusuke Tamura, Kazuo Takada, Yasuo Suzuki
  • Publication number: 20070015057
    Abstract: A nonaqueous electrolyte secondary battery having a positive electrode made of a carbonaceous material, an electrolyte containing a lithium salt, and a negative electrode made of metallic lithium or a material capable of occluding and releasing lithium, wherein said positive electrode is formed from a boronized graphitic material containing boron or a boron compound such that the content of boron therein is 0.05-11 wt %. A method for production of the positive electrode of the nonaqueous electrolyte secondary battery.
    Type: Application
    Filed: September 6, 2006
    Publication date: January 18, 2007
    Applicant: FDK Corporation
    Inventors: Takashi Suzuki, Masanori Nakanishi, Yoshiro Harada, Hiroto Sagisaka
  • Publication number: 20060292447
    Abstract: A non-aqueous electrolyte secondary battery in which a positive electrode formed of a graphite powder and an negative electrode formed of a material capable of absorption/desorption of a lithium metal or lithium are placed to face each other in an electrolyte containing lithium salt. The positive electrode of this battery where a Lc (112) which is the size of crystallite in a c axis direction which is calculated from a (112) diffraction line of a graphite crystal and determined by a powder X-ray diffraction method which is from 4 nm to 30 nm, and a charge capacity at the first cycle which is calculated on the basis of a total weight of the graphite material of the positive electrode filled in the battery is 20 to 50 (mAh/g). Preferably, the graphite powder of the positive electrode has an ratio (A/B) which is the ratio of a specific surface area A determined by a nitrogen absorption (BET) method to a surface area B determined on the basis of an area average diameter of 20 or less.
    Type: Application
    Filed: April 11, 2005
    Publication date: December 28, 2006
    Applicant: FDK CORPORATION
    Inventors: Takashi Suzuki, Toshiyuki Miwa, Hiroto Sagisaka, Kenji Nabekura, Masanori Nakanishi, Minoru Inagaki
  • Publication number: 20040131940
    Abstract: A nonaqueous electrolyte secondary battery having a positive electrode made of a carbonaceous material, an electrolyte containing a lithium salt, and a negative electrode made of metallic lithium or a material capable of occluding and releasing lithium, wherein said positive electrode is formed from a boronized graphitic material containing boron or a boron compound such that the content of boron therein is 0.05-11 wt %. A method for production of the positive electrode of the nonaqueous electrolyte secondary battery.
    Type: Application
    Filed: November 14, 2003
    Publication date: July 8, 2004
    Inventors: Takashi Suzuki, Masanori Nakanishi, Yoshiro Harada, Hiroto Sagisaka
  • Publication number: 20040115531
    Abstract: An alkaline primary cell which is improved in reduction of self-discharge and cell capacity under storage at a high temperature, has a prolonged life and makes use of nickel oxyhydroxide is provided inexpensively. &bgr;-Form nickel oxyhydroxide is contained in a positive electrode mixture as an active material, which contains cobalt and zinc as a substitutional element for solid solution, and has a total amount X+Y of molar ratios of cobalt atom X and zinc atom Y such that 2≦X+Y≦16, with a mixing ratio satisfying the relationship of Y≦3/2×X+1/2 and Y≧2/3×X−1/3, and where a diffraction peak obtained as a result of measurement of X-ray powder diffraction of nickel oxyhydroxide appears only in the vicinity of 18.5° within a range of 2&thgr;=10°-30°.
    Type: Application
    Filed: January 8, 2004
    Publication date: June 17, 2004
    Inventors: Shinichi Ueki, Yoshiro Harada, Mitsuhiro Nakamura, Hiroto Sagisaka, Takeshi Miyazaki