Patents by Inventor Yuzuru Fukushima

Yuzuru Fukushima 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: 20050014069
    Abstract: The invention provides an electrolyte whose battery capacity, cycle characteristics, load characteristics, and low temperature characteristics are all excellent, and a battery using it. A cathode and an anode are layered and wound with a separator and electrolyte layer in between. The electrolyte layer contains a high molecular weight compound and an electrolytic solution containing at least one from the group consisting of vinylethylene carbonate and its derivatives in the range of 0.05 wt % to 5 wt % in total. Therefore, chemical stability of the electrolyte layer is improved. It is preferable that the electrolytic solution further contains ethylene carbonate and propylene carbonate by a mass ratio of ethylene carbonate:propylene carbonate=15-75:85-25.
    Type: Application
    Filed: March 2, 2004
    Publication date: January 20, 2005
    Inventors: Yuzuru Fukushima, Yusuke Fujishige, Fumiko Kimura, Takuya Endo
  • Publication number: 20040229120
    Abstract: Provided is a battery capable of preventing the entry of water even if a sealing width is reduced. A battery element comprising a cathode and an anode is accommodated in a film-shaped casing. The casing includes a metal layer, a resin layer disposed on a side of the metal layer closer to the battery element with an adhesive layer in between, and a resin layer disposed on a side of the metal layer opposite to the side where the resin layer is formed with an adhesive layer in between. The adhesive layer has a water vapor transmission rate of 800 g/m2·day or less for a thickness of 25 &mgr;m at 40° C. and 90% RH and a thickness of 10 &mgr;m or less. Thereby, even if the sealing width is reduced, the entry of water into the battery can be prevented.
    Type: Application
    Filed: March 9, 2004
    Publication date: November 18, 2004
    Inventors: Kazuhito Hatta, Takahiro Endo, Tsuyonobu Hatazawa, Yuzuru Fukushima
  • Patent number: 6814764
    Abstract: A method for producing a cathode active material having superior cell characteristics through single-phase synthesis of a composite material composed of a compound represented by the general formula LixFe1-yMyPO4 and a carbon material positively and a method for producing a non-aqueous electrolyte cell employing the so produced cathode active material. To this end, the cathode active material is prepared by a step of mixing the starting materials for synthesis of the compound represented by the general formula LixFe1-yMyPO4, a step of milling a mixture obtained by the mixing step, a step of compressing the mixture obtained by the mixing step to a preset density and a step of sintering the mixture obtained by the compressing step. A carbon material is added in any one of the above steps prior to the sintering step. The density of the mixture in the compressing step is set to not less than 1.71 g/cm3 and not larger than 2.45 g/cm3.
    Type: Grant
    Filed: September 28, 2001
    Date of Patent: November 9, 2004
    Assignee: Sony Corporation
    Inventors: Mamoru Hosoya, Yuzuru Fukushima, Hideki Sakai, Junji Kuyama
  • Patent number: 6811924
    Abstract: A LiFePO4 carbon composite material is to be synthesized in a single phase satisfactorily to achieve superior cell characteristics. In preparing a cathode active material, a starting material for synthesis of a compound represented by the general formula LixFePO4, where 0<x≦1, is mixed, milled and sintered and a carbon material is added to the resulting mass at an optional time point in the course of mixing, milling and sintering. Li3PO4, Fe3(PO4)2 or its hydrates Fe3(PO4)2.nH2O, where n denotes the number of hydrates, are used as the starting material for synthesis of LixFePO4. The particle size distribution of particles of the starting material for synthesis following the milling with the particle size not less than 3 &mgr;m is set to 2.2% or less in terms of the volumetric integration frequency.
    Type: Grant
    Filed: September 24, 2001
    Date of Patent: November 2, 2004
    Assignee: Sony Corporation
    Inventors: Mamoru Hosoya, Kimio Takahashi, Yuzuru Fukushima
  • Patent number: 6797431
    Abstract: A LiFePO4 carbon composite material is to be synthesized in a single phase satisfactorily to achieve superior cell characteristics. In preparing a cathode active material, starting materials for synthesis of a compound represented by the general formula LixFePO4, where 0<x≦1, are mixed, milled and a carbon material is added to the resulting mass at an optional time point in the course of mixing, milling and sintering. Li3PO4, Fe3(PO4)2 or its hydrates Fe3(PO4)2·nH2O, where n denotes the number of hydrates, are used as the starting materials for synthesis of LixFePO4. The the temperature of a product from said sintering is set to 305° C. or less when said product from said sintering is exposed to atmosphere. The oxygen concentration in a sintering atmosphere is set to 1012 ppm in volume or less at the time point of sintering.
    Type: Grant
    Filed: September 27, 2001
    Date of Patent: September 28, 2004
    Assignee: Sony Corporation
    Inventors: Mamoru Hosoya, Kimio Takahashi, Yuzuru Fukushima
  • Publication number: 20040111873
    Abstract: A method for manufacturing a cathode active material comprising: a mixing step of mixing at least Fe3(PO4)2.nH2O (n designates the number of hydrates and ranges from 0 to 8.) with Li3PO4; and a sintering step of sintering a mixed material obtained in the mixing step when the cathode active material represented by a composition of LixFe1-yMyPO4 (M is at least a kind of materials such as Mn, Cr, Co, Cu, Ni, V, Mo, Ti, Zn, Al, Ga, Mg, B, and Nb, x is located within a range expressed by 0.05≦x≦1.2, and y is located within a range expressed by 0≦y<0.8.) is synthesized, wherein a half-value width of a maximum diffraction peak of the mixed material in an X-ray diffraction using CuK&agr; ray is 1.0° or smaller.
    Type: Application
    Filed: September 26, 2003
    Publication date: June 17, 2004
    Inventors: Tsuyoshi Okawa, Yuzuru Fukushima
  • Publication number: 20040081891
    Abstract: The present invention concerns a non-aqueous electrolyte secondary battery includes a cathode (2) capable of being electrochemically doped with and dedoped from lithium; an anode (3)capable of being electrochemically doped with and dedoped from lithium; and an immobilized non-aqueous electrolyte or a gel electrolyte (4) interposed between the cathode (2) and the anode (3) and obtained by mixing a low viscosity compound with or dissolving a low viscosity compound in a polymer compound. At least one kind of unsaturated carbonate or a cyclic ester compound is added to the low viscosity compound, so that storage characteristics and cyclic characteristics are improved.
    Type: Application
    Filed: August 27, 2003
    Publication date: April 29, 2004
    Inventors: Akira Yamaguchi, Hideaki Ojima, Ken Segawa, Yuzuru Fukushima
  • Patent number: 6656635
    Abstract: A non-aqueous electrolyte secondary cell containing a compound of an olivinic structure as a cathode active material is to be improved in load characteristics and cell capacity. To this end, there is provided a non-aqueous electrolyte secondary cell including a cathode having a layer of a cathode active material containing a compound represented by the general formula LixFe1-yMyPO4, where M is at least one selected from the group consisting of Mn, Cr, Co, Cu, Ni, V, Mo, Ti, Zn, Al, Ga, Mg, B and Nb, with 0.05≦x≦1.2 and 0≦y≦0.8, an anode having a layer of a cathode active material containing the anode active material and a non-aqueous electrolyte, wherein the layer of the cathode active material has a film thickness in a range from 25 to 110 &mgr;m. If a layer of a cathode active material is provided on each surface of a cathode current collector, the sum of the film thicknesses of the layers of the cathode active material ranges between 50 and 220 &mgr;m.
    Type: Grant
    Filed: October 5, 2001
    Date of Patent: December 2, 2003
    Assignee: Sony Corporation
    Inventors: Tsuyoshi Okawa, Mamoru Hosoya, Junji Kuyama, Yuzuru Fukushima
  • Patent number: 6649307
    Abstract: The present invention provides a non-aqueous electrolyte secondary cell including: a cathode containing a manganese oxide or a lithium-manganese composite oxide; an anode containing a lithium metal, a lithium alloy, or a material capable of doping/dedoping lithium; and an electrolyte containing at least two electrolyte salts, one of which is LiBF4 contained in the range from 0.005 mol/l to 0.3 mol/l. This enables to increase the cycle characteristic, preventing deterioration of the cell characteristic caused by a repeated use.
    Type: Grant
    Filed: July 10, 2001
    Date of Patent: November 18, 2003
    Assignee: Sony Corporation
    Inventors: Hideki Terashima, Yuzuru Fukushima, Kimio Takahashi, Hiroko Ohnuma, Kotaro Satori, Akinori Kita
  • Publication number: 20020150816
    Abstract: A non-aqueous electrolyte cell having high discharge capacity, an improved capacity upkeep ratio and optimum cyclic characteristics. The non-aqueous electrolyte cell has a cell device including a strip-shaped cathode material and a strip-shaped anode material, layered and together via a separator and coiled a plural number of times, a non-aqueous electrolyte solution, and a cell can for accommodating cell device and the non-aqueous electrolyte solution. The cathode employs a cathode active material containing a compound of the olivinic structure represented by the general formula LixFe1-yMyPO4, where M is at least one selected from the group consisting of Mn, Cr, Co, Cu, Ni, V, Mo, Ti, Zn, Al, Ga, Mg, B and Nb, with 0.05≦x≦1.2 and 0≦y≦0.8, with the compound being used either singly or in combination with other materials. The ratio of an inner diameter d to an outer diameter D of cell device is selected so that 0.05<d/D<0.5.
    Type: Application
    Filed: October 5, 2001
    Publication date: October 17, 2002
    Inventors: Hideki Sakai, Yuzuru Fukushima, Junji Kuyama, Mamoru Hosoya
  • Publication number: 20020124386
    Abstract: A method for producing a cathode active material having superior cell characteristics through single-phase synthesis of a composite material composed of a compound represented by the general formula LixFe1−yMyPO4 and a carbon material positively and a method for producing a non-aqueous electrolyte cell employing the so produced cathode active material. To this end, the cathode active material is prepared by a step of mixing the starting materials for synthesis of the compound represented by the general formula LixFe1−yMyPO4, a step of milling a mixture obtained by the mixing step, a step of compressing the mixture obtained by the mixing step to a preset density and a step of sintering the mixture obtained by the compressing step. A carbon material is added in any one of the above steps prior to the sintering step. The density of the mixture in the compressing step is set to not less than 1.71 g/cm3 and not larger than 2.45 g/cm3.
    Type: Application
    Filed: September 28, 2001
    Publication date: September 12, 2002
    Inventors: Mamoru Hosoya, Yuzuru Fukushima, Hideki Sakai, Junji Kuyama
  • Publication number: 20020127472
    Abstract: The present invention provides a non-aqueous electrolyte secondary cell including: a cathode containing a manganese oxide or a lithium-manganese composite oxide; an anode containing a lithium metal, a lithium alloy, or a material capable of doping/dedoping lithium; and an electrolyte containing at least two electrolyte salts, one of which is LiBF4 contained in the range from 0.005 mol/l to 0.3 mol/l. This enables to increase the cycle characteristic, preventing deterioration of the cell characteristic caused by a repeated use.
    Type: Application
    Filed: July 10, 2001
    Publication date: September 12, 2002
    Inventors: Hideki Terashima, Yuzuru Fukushima, Kimio Takahashi, Hiroko Ohnuma, Kotaro Satori, Akinori Kita
  • Publication number: 20020122984
    Abstract: A method for producing a cathode active material which produces a spinel type lithium manganese oxide expressed by a general formula: Li1+xMn2−x−yMeyPO4, as the cathode active material, (here, x is expressed by a relation of 0≦x≦0.15 and y is expressed by a relation of 0<y<0.3, and Me is at least one kind of element selected from between Co, Ni, Fe, Cr, Mg and Al). The method comprises a mixing step of mixing raw materials of the spinel type lithium manganese oxide to obtain a precursor; and a sintering step of sintering the precursor obtained in the mixing step to obtain the spinel type lithium manganese oxide. The sintering temperature in the sintering step is located within a range of 800° C. or higher and 900° C. or lower. Accordingly. even when manganese which is inexpensive and abundant in resources is employed as a main material, an excellent cathode performance can be maintained under the environment.
    Type: Application
    Filed: October 19, 2001
    Publication date: September 5, 2002
    Inventors: Hideki Sakai, Yuzuru Fukushima, Kimio Takahashi, Mamoru Hosoya
  • Publication number: 20020114754
    Abstract: An LiFePO4 carbon composite material is to be synthesized in a single phase to realize superior cell characteristics. To this end, in the preparation of a cathode active material, starting materials for synthesis of a compound having the formula LixFePO4, where 0<×≦1, are mixed together, milled and sintered. A carbon material is added at one of these steps. As the starting materials for synthesis for LixFePO4, Li3PO4, Fe3PO4, Fe3(PO4)2 or its hydrate Fe3(PO4)2•nH20), where n is the number of hydrates, are used, and the content of Fe3+ in the total iron in Fe3(PO4)2 or its hydrate Fe3(PO4)2·nH20) is set to 61 wt% or less.
    Type: Application
    Filed: September 24, 2001
    Publication date: August 22, 2002
    Inventors: Mamoru Hosoya, Kimio Takahashi, Yuzuru Fukushima
  • Publication number: 20020106564
    Abstract: A non-aqueous electrolyte secondary cell containing a compound of an olivinic structure as a cathode active material is to be improved in load characteristics and cell capacity. To this end, there is provided a non-aqueous electrolyte secondary cell including a cathode having a layer of a cathode active material containing a compound represented by the general formula LixFe1-yMyPO4, where M is at least one selected from the group consisting of Mn, Cr, Co, Cu, Ni, V, Mo, Ti, Zn, Al, Ga, Mg, B and Nb, with 0.05≦x≦1.2 and 0≦y≦0.8, an anode having a layer of a cathode active material containing the anode active material and a non-aqueous electrolyte, wherein the layer of the cathode active material has a film thickness in a range from 25 to 110 &mgr;m. If a layer of a cathode active material is provided on each surface of a cathode current collector, the sum of the film thicknesses of the layers of the cathode active material ranges between 50 and 220 &mgr;m.
    Type: Application
    Filed: October 5, 2001
    Publication date: August 8, 2002
    Inventors: Tsuyoshi Okawa, Mamoru Hosoya, Junji Kuyama, Yuzuru Fukushima
  • Publication number: 20020106562
    Abstract: A non-aqueous electrolyte cell in which the allowable range of starting material s for synthesis left in a cathode active material is prescribed in order to realize satisfactory cell characteristics. The non-aqueous electrolyte cell includes a cathode containing a cathode active material, an anode containing an anode active material, and a non-aqueous electrolyte, in which the cathode active material is mainly composed of a compound represented by the general formula LixFePO4, where 0<x≦1, with the molar ratio of Li3PO4 to a compound represented by the general formula LixFePO4 to the compound represented by the general formula LixFePO4, which ratio is represented by Li3PO4/LiFePO4, being Li3PO4/LixFePO4≦6.67×10−2.
    Type: Application
    Filed: October 4, 2001
    Publication date: August 8, 2002
    Inventors: Atsushi Sato, Junji Kuyama, Yuzuru Fukushima, Mamoru Hosoya
  • Publication number: 20020106563
    Abstract: A cell in which liquid leakage or destruction may be prevented as the apparent energy density per unit volume of the cell is maintained. The cell uses, as a cathode active material, a compound of an olivinic crystal structure having the formula LixFe1−yMyPO4, where M is at least one selected from the group of Mn, Cr, Co, Cu, Ni, V, Mo, Ti, Zn, Al, Ga, Mg, B and Nb and 0.05≦x≦1.2 and 0≦y≦0.8. By adjusting the amount of the electrolyte solution, the amount of the void in the container is set so as to be not less than 0.14 cc and not more than 3.3 cc per 1 Ah of the cell capacity.
    Type: Application
    Filed: October 5, 2001
    Publication date: August 8, 2002
    Inventors: Tsuyoshi Okawa, Mamoru Hosoya, Junji Kuyama, Yuzuru Fukushima
  • Publication number: 20020102459
    Abstract: An non-aqueous electrolyte cell having superior electronic conductivity and superior cell characteristics. A cathode active material used for the cell is a composite material of a compound having the formula LixFePO4, where 0<x≦1.0, and a carbon material, wherein the specific surface area as found by the Bullnauer Emmet Teller formula is not less than 10.3 m2/g.
    Type: Application
    Filed: September 24, 2001
    Publication date: August 1, 2002
    Inventors: Mamoru Hosoya, Kimio Takahashi, Yuzuru Fukushima
  • Publication number: 20020061274
    Abstract: A LiFePO4 carbon composite material is to be synthesized in a single phase satisfactorily to achieve superior cell characteristics. In preparing a cathode active material, starting materials for synthesis of a compound represented by the general formula LixFePO4, where 0<x≦1, are mixed, milled and a carbon material is added to the resulting mass at an optional time point in the course of mixing, milling and sintering. Li3PO4, Fe3(PO4)2 or its hydrates Fe3(PO4)2·nH2O, where n denotes the number of hydrates, are used as the starting materials for synthesis of LixFePO4. The the temperature of a product from said sintering is set to 305° C. or less when said product from said sintering is exposed to atmosphere. The oxygen concentration in a sintering atmosphere is set to 1012 ppm in volume or less at the time point of sintering.
    Type: Application
    Filed: September 27, 2001
    Publication date: May 23, 2002
    Inventors: Mamoru Hosoya, Kimio Takahashi, Yuzuru Fukushima
  • Publication number: 20020059719
    Abstract: A LiFePO4 carbon composite material is to be synthesized in a single phase satisfactorily to prevent the deterioration of the performance of the cathode active material from occurring and achieve superior cell characteristics. In preparing a cathode active material, starting materials for synthesis of a compound represented by the general formula LixFePO4, where 0<x≦1, are mixed, milled and a carbon material is added to the resulting mass at an optional time point in the course of mixing, milling and sintering. Li3PO4, Fe3(PO4)2 or its hydrates Fe3(PO4)2.nH2O, where n denotes the number of hydrates, are used as the starting materials for synthesis of LixFePO4. The temperature of a product from said sintering is set to 305° C. or less when said product from said sintering is exposed to atmosphere.
    Type: Application
    Filed: September 19, 2001
    Publication date: May 23, 2002
    Applicant: Sony Corporation
    Inventors: Mamoru Hosoya, Kimio Takahashi, Yuzuru Fukushima