Patents by Inventor Yoshinobu Yasunaga

Yoshinobu Yasunaga 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: 9318742
    Abstract: An object is to provide a positive active material for nonaqueous electrolyte secondary battery, which is capable of providing a battery with excellent cycle performance. Provided are a positive active material for nonaqueous electrolyte secondary battery, which includes an Fe-containing lithium vanadium phosphate compound having a NASICON-type structure, wherein in the Fe-containing lithium vanadium phosphate compound, the percentage of iron atoms relative to the sum of vanadium and iron atoms is 2% or more and 20% or less; and the like.
    Type: Grant
    Filed: February 16, 2011
    Date of Patent: April 19, 2016
    Assignee: GS YUASA INTERNATIONAL LTD.
    Inventors: Yukiko Fujino, Yoshinobu Yasunaga, Toru Tabuchi, Tokuo Inamasu, Toshiyuki Nukuda
  • Patent number: 9172072
    Abstract: [PROBLEM] In space-conservative fashion, at low cost, and with high efficiency, to carry out absorption of gas produced at the interior of a battery. [SOLUTION MEANS] Secondary battery 21 is provided with case 3 in which positive electrode 10 and negative electrode 11 are sealed together with electrolyte, and with explosion prevention valve 4 for allowing escape of high-pressure gas present at the interior of case 3 when pressure within case 3 rises; and is further provided with gas absorber 13 or 14 for absorbing high-pressure gas. Gas absorber 13, includes gas-absorbent material 6 and capsule 5, which comprises hot-melt material, and is provided within case 3, this capsule 5 including, at the interior thereof, gas-absorbent material 6.
    Type: Grant
    Filed: August 26, 2011
    Date of Patent: October 27, 2015
    Assignees: GS Yuasa International Ltd, KURITA WATER INDUSTRIES LTD.
    Inventors: Yohei Shibata, Yoshinobu Yasunaga, Tsutomu Watanabe, Tokuo Inamasu, Ryoichi Okuyama, Minoru Yagi, Hiroshi Obuse, Shinichi Wada
  • Patent number: 8822080
    Abstract: The present invention provides a Li3V2(PO4)3-based positive active material for a lithium secondary battery, which has high discharge capacity and excellent storage performance, particularly high-temperature storage performance; and a lithium secondary battery made using the positive active material. The positive active material for a lithium secondary battery has general formula Li3V2(PO4)3?x(BO3)x (0<x?2?2). It is preferable that x be 2?7?x?2?3. Also provided are a positive electrode for a lithium secondary battery containing the positive active material; and a lithium secondary battery including the positive electrode.
    Type: Grant
    Filed: October 27, 2010
    Date of Patent: September 2, 2014
    Assignee: GS Yuasa International Ltd.
    Inventors: Yukiko Fujino, Yoshinobu Yasunaga, Toru Tabuchi, Tokuo Inamasu, Toshiyuki Nukuda
  • Patent number: 8771877
    Abstract: Disclosed is a positive electrode material for nonaqueous electrolyte secondary batteries, which comprises a porous body composed of a material containing a polyanion. Also disclosed is a method for producing such a positive electrode material for nonaqueous electrolyte secondary batteries. When a carbon coating is formed on the surface of a material containing a polyanion of lithium iron phosphate or the like by a conventional method, the capacity during low rate discharge is improved but the capacity is not sufficient. In the present invention, the positive electrode material for nonaqueous electrolyte secondary batteries, which comprises a porous body composed of a material containing a polyanion, has a structure wherein the inner walls of the pores of the porous body are provided with a layered carbon, for improving the discharge capacity.
    Type: Grant
    Filed: December 28, 2007
    Date of Patent: July 8, 2014
    Assignee: GS Yuasa International Ltd.
    Inventors: Yoshinobu Yasunaga, Akihiro Fujii, Tokuo Inamasu
  • Patent number: 8647777
    Abstract: Disclosed is a mixed material of lithium iron phosphate and carbon, which contains secondary particles as aggregates of lithium iron phosphate primary particles and a fibrous carbon which is present inside the secondary particles. An electrode containing such a mixed material, a battery comprising such an electrode, a method for producing such a mixed material, and a method for producing a battery are also disclosed.
    Type: Grant
    Filed: October 13, 2006
    Date of Patent: February 11, 2014
    Assignee: GS Yuasa International Ltd.
    Inventors: Yoshinobu Yasunaga, Tokuo Inamasu, Akihiro Fujii, Toshiyuki Nukuda
  • Publication number: 20130171483
    Abstract: [PROBLEM] In space-conservative fashion, at low cost, and with high efficiency, to carry out absorption of gas produced at the interior of a battery. [SOLUTION MEANS] Secondary battery 21 is provided with case 3 in which positive electrode 10 and negative electrode 11 are sealed together with electrolyte, and with explosion prevention valve 4 for allowing escape of high-pressure gas present at the interior of case 3 when pressure within case 3 rises; and is further provided with gas absorber 13 or 14 for absorbing high-pressure gas. Gas absorber 13, includes gas-absorbent material 6 and capsule 5, which comprises hot-melt material, and is provided within case 3, this capsule 5 including, at the interior thereof, gas-absorbent material 6.
    Type: Application
    Filed: August 26, 2011
    Publication date: July 4, 2013
    Applicants: KURITA WATER INDUSTRIES LTD., GS YUASA INTERNATIONAL LTD.
    Inventors: Yohei Shibata, Yoshinobu Yasunaga, Tsutomu Watanabe, Tokuo Inamasu, Ryoichi Okuyama, Minoru Yagi, Hiroshi Obuse, Shinichi Wada
  • Patent number: 8431271
    Abstract: The invention provides a polyanion-based positive active material which can improve storage stability (especially, high temperature storage stability), charge and discharge cycle performance and the like of a lithium secondary battery, and a lithium secondary battery using the same. The positive active material for a lithium ion secondary battery contains lithium iron cobalt phosphate represented by the general formula: LiyFe(1-x)CoxPO4(0<x?0.019, 0?y?1.2). By using the positive active material for a lithium secondary battery, high temperature storage stability and charge and discharge cycle performance can be improved in comparison with a case where LiyFePO4 containing no Co is used. By using the positive active material, a lithium ion secondary battery can be suitable for applications in fields of electric automobiles and industrial batteries in which long lives, high capacities, and high output powers are required.
    Type: Grant
    Filed: May 22, 2009
    Date of Patent: April 30, 2013
    Assignee: GS Yuasa International Ltd.
    Inventors: Yukiko Fujino, Yoshinobu Yasunaga, Akihiro Fujii, Yohei Shibata, Mariko Kohmoto, Takashi Egawa, Toru Tabuchi, Hiroe Nakagawa, Tokuo Inamasu, Toshiyuki Nukuda
  • Publication number: 20120308893
    Abstract: An object is to provide a positive active material for nonaqueous electrolyte secondary battery, which is capable of providing a battery with excellent cycle performance. Provided are a positive active material for nonaqueous electrolyte secondary battery, which includes an Fe-containing lithium vanadium phosphate compound having a NASICON-type structure, wherein in the Fe-containing lithium vanadium phosphate compound, the percentage of iron atoms relative to the sum of vanadium and iron atoms is 2% or more and 20% or less; and the like.
    Type: Application
    Filed: February 16, 2011
    Publication date: December 6, 2012
    Applicant: GS YUASA INTERNATIONAL LTD.
    Inventors: Yukiko Fujino, Yoshinobu Yasunaga, Toru Tabuchi, Tokuo Inamasu, Toshiyuki Nukuda
  • Publication number: 20120219862
    Abstract: The present invention provides a Li3V2(PO4)3-based positive active material for a lithium secondary battery, which has high discharge capacity and excellent storage performance, particularly high-temperature storage performance; and a lithium secondary battery made using the positive active material. The positive active material for a lithium secondary battery has general formula Li3V2(PO4)3-x(BO3)x (0<x?2?2). It is preferable that x be 2?7?x?2?3. Also provided are a positive electrode for a lithium secondary battery containing the positive active material; and a lithium secondary battery including the positive electrode.
    Type: Application
    Filed: October 27, 2010
    Publication date: August 30, 2012
    Applicant: GS YUASA INTERNATIONAL LTD.
    Inventors: Yukiko Fujino, Yoshinobu Yasunaga, Toru Tabuchi, Tokuo Inamasu, Toshiyuki Nukuda
  • Publication number: 20110068293
    Abstract: The invention provides a polyanion-based positive active material which can improve storage stability (especially, high temperature storage stability), charge and discharge cycle performance and the like of a lithium secondary battery, and a lithium secondary battery using the same. The positive active material for a lithium ion secondary battery contains lithium iron cobalt phosphate represented by the general formula: LiyFe(1-x)CoxPO4 (0<x?0.019, 0?y?1.2). By using the positive active material for a lithium secondary battery, high temperature storage stability and charge and discharge cycle performance can be improved in comparison with a case where LiyFePO4 containing no Co is used. By using the positive active material, a lithium ion secondary battery can be suitable for applications in fields of electric automobiles and industrial batteries in which long lives, high capacities, and high output powers are required.
    Type: Application
    Filed: May 22, 2009
    Publication date: March 24, 2011
    Applicant: GS YUASA INTERNATIONAL LTD.
    Inventors: Yukiko Fujino, Yoshinobu Yasunaga, Akihiro Fujii, Yohei Shibata, Mariko Kohmoto, Takashi Egawa, Toru Tabuchi, Hiroe Nakagawa, Tokuo Inamasu, Toshiyuki Nukuda
  • Publication number: 20090297952
    Abstract: Disclosed is a positive electrode material for nonaqueous electrolyte secondary batteries, which comprises a porous body composed of a material containing a polyanion. Also disclosed is a method for producing such a positive electrode material for nonaqueous electrolyte secondary batteries. When a carbon coating is formed on the surface of a material containing a polyanion of lithium iron phosphate or the like by a conventional method, the capacity during low rate discharge is improved but the capacity is not sufficient. In the present invention, the positive electrode material for nonaqueous electrolyte secondary batteries, which comprises a porous body composed of a material containing a polyanion, has a structure wherein the inner walls of the pores of the porous body are provided with a layered carbon, for improving the discharge capacity.
    Type: Application
    Filed: December 28, 2007
    Publication date: December 3, 2009
    Inventors: Yoshinobu Yasunaga, Akihiro Fujii, Tokuo Inamasu
  • Publication number: 20090236564
    Abstract: Disclosed is a mixed material of lithium iron phosphate and carbon, which contains secondary particles as aggregates of lithium iron phosphate primary particles and a fibrous carbon which is present inside the secondary particles. An electrode containing such a mixed material, a battery comprising such an electrode, a method for producing such a mixed material, and a method for producing a battery are also disclosed.
    Type: Application
    Filed: October 13, 2006
    Publication date: September 24, 2009
    Applicant: GS YUASA CORPORATION
    Inventors: Yoshinobu Yasunaga, Tokuo Inamasu, Akihiro Fujii, Toshiyuki Nukuda
  • Patent number: 7151069
    Abstract: The feature of the process for ultra-low alloy catalyst loading electrode according to this invention is to reduce its alloy formation period of aging process subsequent to hydrogen reduction process of catalyst ions after ion exchange process of proton for their ions in the cluster of the polymer electrolyte on the surface of the carbon powder. The process is able to drastically shorten the aging time with temperature rise beyond 200° C. up to 400° C. under hydrogen atmosphere for the formation of alloy catalyst, for example Pt—Ru binary by the additional processes of pre-treatment of substituting K+, Na+, Li+, Rb+, Cs+, Mg2+, Ca2+, Ba2+, Fe2+, Sr2+, Ra2+, Cu2+, Ag+, Zn2+, Ni2+, or Co2+ for proton before the hydrogen reduction process. The further post-treatment of substituting K+, Na+, Li+, Rb+, Cs+, Mg2+, Ca2+, Ba2+, Fe2+, Sr2+, Ra2+, Cu2+, Ag+, Zn2+, Ni2+, or Co2+ for proton before the ion exchange process is more preferable. This new process is little harmful to the CO tolerance performance of PEFC.
    Type: Grant
    Filed: July 16, 2004
    Date of Patent: December 19, 2006
    Assignee: Japan Storage Battery Co., Ltd.
    Inventors: Yoshinobu Yasunaga, Shuji Hitomi
  • Publication number: 20050026772
    Abstract: The feature of the process for ultra-low alloy catalyst loading electrode according this invention is to reduce its alloy formation period of aging process subsequent to hydrogen reduction process of catalyst ions after ion exchange process of their ions and proton in the cluster of the polymer electrolyte on the surface of the carbon powder. The process is able to drastically shorten the aging time with temperature rise beyond 200° C. up to 400° C. under hydrogen atmosphere for the formation of Pt—Ru binary alloy for example catalyst by the additional processes of pre-treatment of K+, Na+, Li+, Rb+, Cs+, Mg2+, Ca2+, Ba2+, Fe2+, Sr2+, Ra2+, Cu2+, Ag+, Zn2+, Ni2+, and Co2+ ions substitution for proton before the hydrogen reduction process. More preference, the further post-treatment of K+, Na+, Li+, Rb+, Cs+, Mg2+, Ca2+, Ba2+, Fe2+, Sr2+, Ra2+, Cu2+, Ag+, Zn2+, Ni2+, and Co2+ ions substitution for proton before the ion exchange process.
    Type: Application
    Filed: July 16, 2004
    Publication date: February 3, 2005
    Inventors: Yoshinobu Yasunaga, Shuji Hitomi