Patents by Inventor Masahisa Fujimoto

Masahisa Fujimoto 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: 6465131
    Abstract: A lithium secondary cell having incorporated therein a positive electrode or negative electrode active substance which is a compound sulfide having substantially the same crystal structure as stannous sulfide (SnS) or a lithium-containing compound sulfide comprising said compound sulfide and lithium contained therein, said compound sulfide comprising at least one transition metal selected from among copper (Cu), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co) and nickel (Ni), tin and sulfur. This stabilizes the crystal structure of SnS serving as the active substance, giving the cell practically useful charge-discharge cycle characteristics.
    Type: Grant
    Filed: June 6, 2000
    Date of Patent: October 15, 2002
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Yasuyuki Kusumoto, Masahisa Fujimoto, Shin Fujitani
  • Patent number: 6462936
    Abstract: The solid electrolytic capacitor of the invention contains an anode, a dielectric film formed on the anode by anodic oxidation, a solid electrolytic layer formed on the dielectric film, and a cathode connected with the solid electrolytic layer, the solid electrolytic layer being made from a conducting polymer obtained by doping with alkyl sulfonic acid ions, a polymer including a heterocyclic monomer unit represented by the following general formula as a repeating unit: The solid electrolytic capacitor of the invention has large capacitance and exhibits low impedance in a high frequency region.
    Type: Grant
    Filed: April 2, 2001
    Date of Patent: October 8, 2002
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masahisa Fujimoto, Shin Fujitani, Koji Nishio
  • Patent number: 6436572
    Abstract: A negative electrode for a nonaqueous electrolyte secondary battery and a nonaqueous electrolyte secondary battery including the negative electrode. The negative electrode is made from aluminum powder or aluminum alloy powder coated with carbon and a conductive polymer. Since aluminum or aluminum alloy has a theoretical maximum capacity as high as 1200 mAh/g, a battery having aluminum or aluminum alloy as the negative electrode material has a high capacity.
    Type: Grant
    Filed: January 31, 2000
    Date of Patent: August 20, 2002
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masahiro Iyori, Masahisa Fujimoto, Shin Fujitani, Koji Nishio
  • Publication number: 20020090552
    Abstract: In a non-aqueous electrolyte battery provided with a positive electrode, a negative electrode, and a non-aqueous electrolyte using an organic solvent, at least one type of ferrite, FeS2, and a transition metal oxide (except for LiCoO2) having crystal structure of space group R3m is used as a positive electrode material for a positive electrode, and a negative electrode material containing lithium is used for a negative electrode.
    Type: Application
    Filed: November 7, 2001
    Publication date: July 11, 2002
    Applicant: Sanyo Electric Co., Ltd.
    Inventors: Yasuyuki Kusumoto, Masahisa Fujimoto, Shin Fujitani, Masahide Miyake
  • Publication number: 20020090550
    Abstract: A secondary battery is characterized by using an organic material including carbon having a conjugate electron cloud and coupled with an electron attractive group; or a material obtained by baking a fluorocarbon polymer or graphite fluoride in an inert atmosphere at a temperature in the range of from the decomposition start temperature to 1000° C., as a positive electrode active material for the secondary battery.
    Type: Application
    Filed: November 9, 2001
    Publication date: July 11, 2002
    Inventors: Hideyuki Koga, Masahisa Fujimoto, Shin Fujitani
  • Publication number: 20020086215
    Abstract: An electrode for a lithium secondary battery in which an alloy thin film containing Sn (tin) and In (indium) is formed on the surface of a current collector having a surface roughness Ra of 0.1 &mgr;m or more, and a lithium secondary battery using thereof.
    Type: Application
    Filed: November 13, 2001
    Publication date: July 4, 2002
    Inventors: Noriyuki Tamura, Daizo Jito, Ryuji Ohshita, Masahisa Fujimoto, Maruo Kamino, Shin Fujitani
  • Patent number: 6403258
    Abstract: In a lithium secondary battery provided with a positive electrode, a negative electrode, and a non-aqueous electrolyte, a tungsten oxide W20O58 or W18O49, or the tungsten oxide to which lithium is added, or a tungsten composite oxide comprising a tungsten oxide containing at least one type of metal element selected from the group consisting of Mn, Cu, V, Cr, Fe, Co, and Ni and having a W20O58-type or W18O49-type crystal structure or the tungsten composite oxide to which lithium is added is used as a positive electrode active material for said positive electrode or a negative electrode active material for said negative electrode.
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: June 11, 2002
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Seiji Yoshimura, Masahisa Fujimoto, Shin Fujitani
  • Patent number: 6383685
    Abstract: In a lithium secondary battery provided with a positive electrode, a negative electrode, and a non-aqueous electrolyte, a composite oxide represented by a chemical formula MXW1−XOY (wherein M denotes at least one type of metal element selected from the group consisting of Cu, V, Cr, Mn, Fe, Co, and Ni; and the conditions of 0<X≦0.46 and 1.5≦Y≦2.5 are satisfied) and having a rutile-type crystal structure or the composite oxide to which lithium is added is used as a positive electrode active material for said positive electrode or a negative electrode active material for said negative electrode.
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: May 7, 2002
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Seiji Yoshimura, Masahisa Fujimoto, Shin Fujitani
  • Patent number: 6383684
    Abstract: In a lithium secondary battery provided with a positive electrode, a negative electrode, and a non-aqueous electrolyte, a composite oxide represented by a chemical formula MXW1-XOY (wherein M denotes at least one type of metal element selected from the group consisting of Cu, V, Cr, Mn, Fe, Co, and Ni; and the conditions of 0<X<0.46 and 2.5≦Y≦3.5 are satisfied) and having a monoclinic crystal structure or the composite oxide to which lithium is added is used as a positive electrode active material for said positive electrode or a negative electrode active material for said negative electrode.
    Type: Grant
    Filed: March 23, 2000
    Date of Patent: May 7, 2002
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Seiji Yoshimura, Masahisa Fujimoto, Shin Fujitani
  • Publication number: 20020034687
    Abstract: A rechargeable lithium battery using an Li alloying metal as the active material of at least one of its positive and negative electrodes. The metal active material is covered with a thin film which is nonreactive with Li ions, permits passage of Li ions but does not have an Li ion conductivity.
    Type: Application
    Filed: July 16, 2001
    Publication date: March 21, 2002
    Inventors: Noriyuki Tamura, Masahisa Fujimoto, Maruo Kamino, Shin Fujitani, Hiromasa Yagi, Yoichi Domoto, Hisaki Tarui, Ryuji Ohshita, Ikuo Yonezu
  • Publication number: 20020009639
    Abstract: The present invention provides an improved electrode material for a lithium secondary battery to provide a lithium secondary battery that is light in weight and has high energy density. Sulfur and a catalyst material such as active carbon, and the like, that reduces activation energy of an addition reaction of lithium to sulfur and allows the reaction to occur at not greater than 60 ° C., are included in the electrode material.
    Type: Application
    Filed: April 24, 2001
    Publication date: January 24, 2002
    Inventors: Masahide Miyake, Masahisa Fujimoto, Shin Fujitani
  • Patent number: 6319633
    Abstract: A rechargeable lithium battery has a positive electrode, a negative electrode and a non-aqueous electrolyte. The active material of the positive or negative electrode is tungsten complex sulfide, either with or without addition of lithium thereto. The tungsten complex sulfide contains tungsten, sulfur and at least one transition metal selected from Cu, V, Cr, Mn, Fe, Co and Ni, and has substantially the same crystal structure as WS2.
    Type: Grant
    Filed: February 14, 2000
    Date of Patent: November 20, 2001
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Hiroaki Ikeda, Masahisa Fujimoto, Shin Fujitani
  • Patent number: 6300009
    Abstract: In a lithium secondary battery of this invention, an active material of either a positive electrode or a negative electrode includes a composite sulfide having the same crystal structure as MoS2 or Mo2S3, or the composite sulfide including lithium, and the composite sulfide is represented by a composition formula, MXMo1−XSY, wherein M is at least one element selected from the group consisting of Cu, V, Cr, Mn, Fe, Co, Ni, Ti, Y, Cd, In, La, Ce, Pr, Nd, Sm, W, Pt, Pb, Ca, Sr and Ba; 0<X<0.46; and 1.5≦Y≦2.0. Thus, the lithium secondary battery using a molybdenum composite sulfide as an active material of a positive or negative electrode can attain good charge-discharge cycle performance.
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: October 9, 2001
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Toshikazu Yoshida, Yoshinori Kida, Masahisa Fujimoto, Shin Fujitani
  • Patent number: 6153336
    Abstract: A lithium secondary battery includes a positive electrode having a complex oxide of lithium and titanium as an active material, the composition of which before initial discharge is represented by Li.sub.x Ti.sub.3-x O.sub.4 (1.ltoreq.x.ltoreq.1.5), a negative electrode having an intercalation compound as an active material, the composition of which before initial discharge is represented by C.sub.y Li (6.ltoreq.y.ltoreq.6.5), and a nonaqueous electrolyte. A low voltage lithium secondary battery having about 1.5 V of discharge voltage is provided.
    Type: Grant
    Filed: August 27, 1998
    Date of Patent: November 28, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Yoshinori Kida, Masahisa Fujimoto, Toshiyuki Nohma, Koji Nishio
  • Patent number: 6143213
    Abstract: The present invention discloses a secondary cell. The secondary cell comprises a positive electrode, a negative electrode which is made of a carbon material, and non-aqueous electrolytic solution, wherein the secondary cell is characterized in that the carbon material as the material of the negative electrode is produced by carbonizing natural high polymers.
    Type: Grant
    Filed: August 9, 1993
    Date of Patent: November 7, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Nobuhiro Furukawa, Masahisa Fujimoto, Noriyuki Yoshinaga, Koji Ueno
  • Patent number: 6132904
    Abstract: A polyelectrolytic battery wherein a porous film having a polyelectrolyte impregnated into its cavities is interposed between a positive electrode and a negative electrode, the porous film having a porosity of not less than 80% and the polyelectrolyte impregnated therein at a ratio of 20 to 90% by volume of the cavities thereof. Another polyelectrolytic battery includes a positive electrode, a negative electrode including a carbon material, and a polyelectrolytic film interposed between the positive and negative electrodes, the positive and negative electrodes each containing a polyelectrolyte composed of a high polymer having a polystyrene main chain and a side chain of polyethlene oxide and a lithium salt.
    Type: Grant
    Filed: July 22, 1998
    Date of Patent: October 17, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Maruo Kamino, Makoto Uesugi, Masahisa Fujimoto, Toshiyuki Nohma, Koji Nishio
  • Patent number: 6132903
    Abstract: Provided is a lithium secondary battery which has a large discharge capacity and good charge-discharge cycle characteristics comprising a negative electrode in which the lithium ion-occlusion material is an amorphous material consisting essentially of B.sub.2 O.sub.3 or an amorphous material consisting essentially of B.sub.2 O.sub.2 and an oxide whose cation-oxygen bond strength is smaller than 335 kJ/mole.
    Type: Grant
    Filed: July 17, 1998
    Date of Patent: October 17, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Masahisa Fujimoto, Toshiyuki Nohma, Koji Nishio
  • Patent number: 6114070
    Abstract: A lithium secondary battery comprising a nonaqueous electrolyte obtained by dissolving an electrolytic salt in a solvent, a negative electrode comprising a negative electrode material and a positive electrode comprising a positive electrode active material, the electrolytic salt comprising: at least one electrolytic salt A selected from the group consisting of LiPF.sub.6, LiAsF.sub.6, LiSbF.sub.6, LiBF.sub.4, LiBiF.sub.4, LiAlF.sub.4, LiGaF.sub.4, LiInF.sub.4 and LiClO.sub.4, and at least one electrolytic salt B selected from the group consisting of LiN(C.sub.n F.sub.2n+1 SO.sub.2).sub.2 wherein n is an integer of 1, 2, 3 or 4 and LiC(C.sub.m F.sub.2m+1 SO.sub.2).sub.3 wherein m is an integer of 1, 2, 3 or 4. The battery is superior in the aspects of storage characteristic in a charged condition.
    Type: Grant
    Filed: April 29, 1998
    Date of Patent: September 5, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Toshikazu Yoshida, Ryuji Ohshita, Masahisa Fujimoto, Toshiyuki Nohma, Koji Nishio
  • Patent number: 6040090
    Abstract: A non-aqueous electrolyte battery according to the invention includes a positive electrode using a lithium-metal compound oxide as a positive electrode material, a negative electrode and a non-aqueous electrolyte solution, the battery employing a positive electrode material composed of the lithium-metal compound oxide which contains at least Ni, Co and Mn, and has a peak with a full width at half maximum of not greater than 0.22.degree. in a range of 2.theta.=18.71.+-.0.25.degree. as measured by the powder X-ray diffraction analysis using a Cu-K.alpha. X-ray source or employing a positive electrode material composed of a lithium-metal compound oxide which contains at least Ni, Co and Mn, and a non-aqueous electrolyte solution which includes a solvent containing ethylene carbonate and a solute containing at least one type of fluorine-containing compound.
    Type: Grant
    Filed: April 14, 1998
    Date of Patent: March 21, 2000
    Assignee: Sanyo Electric Co., Ltd.
    Inventors: Takuya Sunagawa, Hiroshi Watanabe, Ryuji Ohshita, Masahisa Fujimoto, Toshiyuki Nohma, Koji Nishio
  • Patent number: 5993997
    Abstract: Provided is a novel lithium secondary battery comprising a positive electrode comprising a compound capable of occluding and discharging lithium, a negative electrode composed mainly of a carbon material which comprises a graphite as an only or as a principal component, a separator between said positive electrode and said negative electrode; and an electrolyte solution of an electrolyte solute dissolved in a solvent comprising at least one specific cyclic compound. The lithium secondary battery has a large capacity, small self-discharge rate and excellent cycle characteristics and high charge-discharge efficiency.
    Type: Grant
    Filed: March 30, 1998
    Date of Patent: November 30, 1999
    Assignee: Sanyo Electric Co., Ltd
    Inventors: Masahisa Fujimoto, Noriyuki Yoshinaga, Koji Ueno, Nobuhiro Furukawa, Toshiyuki Nohma, Masatoshi Takahashi