Patents by Inventor Shohei Yokoyama

Shohei Yokoyama 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: 20100173204
    Abstract: An object of the present invention is to provide a lithium secondary battery which has improved capacity, durability, and rate characteristic as compared with conventional lithium secondary batteries. A plate-like particle or a film for a lithium secondary battery cathode active material contains cobalt and lithium and has a layered rock salt structure. The (003) plane is oriented so as to intersect the plate surface of the particle or film.
    Type: Application
    Filed: December 22, 2009
    Publication date: July 8, 2010
    Applicant: NGK Insulators, Ltd.
    Inventors: Ryuta Sugiura, Nobuyuki Kobayashi, Shohei Yokoyama, Tsutomu Nanataki
  • Publication number: 20100159326
    Abstract: An object of the present invention is to provide a lithium secondary battery which has improved capacity, durability, and rate characteristic as compared with conventional lithium secondary batteries. A plate-like particle or a film for a lithium secondary battery cathode active material is represented by the following general formula: General formula: Lip(Nix,Coy,Alz)O2 (wherein 0.9?p?1.3, 0.6<x?0.9, 0.1<y?0.3, 0?z?0.2, x+y+z=1) The particle or the film contains cobalt and lithium and has a layered rock salt structure. The (003) plane is oriented so as to intersect the plate surface of the particle or film.
    Type: Application
    Filed: December 22, 2009
    Publication date: June 24, 2010
    Applicant: NGK Insulators, Ltd.
    Inventors: Ryuta Sugiura, Nobuyuki Kobayashi, Shohei Yokoyama, Tsutomu Nanataki
  • Publication number: 20100159333
    Abstract: By exposing the crystal plane (a plane other than the (003) plane: e.g., the (101) plane and (104) plane) through which lithium ions are favorably intercalated and deintercalated, more to an electrolyte, characteristics such as cell capacity is improved. The present invention relates a plate-like particle for a lithium secondary battery cathode active material. The particle has a layered rock salt structure. The (003) plane is oriented in a direction intersecting a particle plate surface. The porosity is 10% or less.
    Type: Application
    Filed: December 22, 2009
    Publication date: June 24, 2010
    Applicant: NGK Insulators, Ltd.
    Inventors: Ryuta SUGIURA, Nobuyuki Kobayashi, Shohei Yokoyama, Tsutomu Nanataki
  • Publication number: 20100159330
    Abstract: An object of the present invention is to provide a lithium secondary battery which has improved capacity, durability, and the other characteristic as compared with conventional lithium secondary batteries. [Means for Solution] A plate-like particle or a film for a lithium secondary battery cathode active material has a layered rock salt structure. The lithium ion gateway plane is oriented in parallel with a plate surface, which is a surface orthogonal to a thickness direction of the particle and thus exposed at the plate surface, a plurality of layers are stacked together in the thickness direction, and while the layers have the same crystal axis in the thickness direction, as for the plate surface direction perpendicular to the thickness direction, the layers have different crystal axes.
    Type: Application
    Filed: December 22, 2009
    Publication date: June 24, 2010
    Applicant: NGK Insulators, Ltd.
    Inventors: Ryuta SUGIURA, Nobuyuki Kobayashi, Shohei Yokoyama, Tsutomu Nanataki
  • Publication number: 20100159325
    Abstract: An object of the present invention is to provide a multi-component system (cobalt-nickel-manganese three-component system) cathode active material for a lithium secondary battery which has improved characteristic as compared with conventional lithium secondary batteries and a layered rock salt structure. A plate-like particle or a film for a lithium secondary battery cathode active material is represented by the following general formula: Lip(Cox,Niy,Mnz)O2??General formula (wherein 0.97?p?1.07, 0.1<x?0.4, 0.3<y?0.5, 0.1<z?0.5, x+y+z=1) The particle or the film contains cobalt and lithium and has a layered rock salt structure. The (003) plane is oriented so as to intersect the plate surface of the particle or film.
    Type: Application
    Filed: December 22, 2009
    Publication date: June 24, 2010
    Applicant: NGK Insulators, Ltd.
    Inventors: Ryuta SUGIURA, Nobuyuki Kobayashi, Shohei Yokoyama, Tsutomu Nanataki, Akira Urakawa
  • Publication number: 20100159329
    Abstract: An object of the present invention is to improve the characteristics such as cell capacity, by raising the exposure of a crystal plane (a plane other than the (003) plane: e.g., (101) plane and (104) plane), through which lithium ions are favorably intercalated and deintercalated, to an electrolyte. A plate-like particle or a film for a lithium secondary battery cathode active material has a layered rock salt structure. A plane other than the (003) plane is oriented in parallel with the plate surface (a surface orthogonal to a thickness direction) and step-like structures are two-dimensionally formed along the plate surface.
    Type: Application
    Filed: December 22, 2009
    Publication date: June 24, 2010
    Applicant: NGK Insulators, Ltd.
    Inventors: Ryuta SUGIURA, Nobuyuki Kobayashi, Shohei Yokoyama, Tsutomu Nanataki
  • Publication number: 20100159332
    Abstract: An object of the present invention is to provide a lithium secondary battery which has improved capacity, durability, and rate characteristic as compared with conventional lithium secondary batteries. A plate-like particle or a film for a lithium secondary battery cathode active material has a layered rock salt structure. The (003) plane is oriented in a direction intersecting the direction of the plate surface of the particle or film.
    Type: Application
    Filed: December 22, 2009
    Publication date: June 24, 2010
    Applicant: NGK Insulators, Ltd.
    Inventors: Ryuta SUGIURA, Nobuyuki Kobayashi, Shohei Yokoyama
  • Publication number: 20100119800
    Abstract: A ceramic sheet 20 is produced by a method in which inorganic particles including, as a main component, an oxide represented by general formula ABO3 and containing a volatile component are mixed such that the A/B ratio is 1.05 or more, the inorganic particles are formed into a self-supported planar shaped body with a thickness of 30 ?m or less, and the shaped body is fired, without an inactive layer or with an inactive layer which does not substantially react with the shaped body and is disposed adjacent to the shaped body, at a temperature-rising rate of 30° C./min or more in a temperature range which is equal to or higher than a temperature at which the volatile component is volatilized.
    Type: Application
    Filed: November 4, 2009
    Publication date: May 13, 2010
    Applicant: NGK Insulators, Ltd.
    Inventors: Shohei Yokoyama, Nobuyuki Kobayashi, Tsutomu Nanataki
  • Patent number: 7700067
    Abstract: A crystallographically-oriented ceramic including first regions, in which crystal nuclei remain and which contain a specific element in a predetermined concentration range and extend at least partially in a layered shape along a crystal plane, and second regions, which contain the specific element in a different concentration range from the first regions and extend at least partially in a layered shape along the crystal plane. The regions are alternately repeated, and a compositional distribution exists in a direction orthogonal to the crystal plane. In the first region, the concentration of Na is higher, the concentration of K is lower, the concentration of Nb is lower, and the concentration of Ta is higher than the second region, and in the second region, the concentration of Na is lower, the concentration of K is higher, the concentration of Nb is higher, and the concentration of Ta is lower than the first region.
    Type: Grant
    Filed: February 22, 2008
    Date of Patent: April 20, 2010
    Assignee: NGK Insulators, Ltd.
    Inventors: Shohei Yokoyama, Nobuyuki Kobayashi, Tsutomu Nanataki
  • Publication number: 20090189489
    Abstract: An actuator includes a fired ceramic substrate having a space opened downward, a first electrode formed on the upper surface of the fired ceramic substrate above the space, a piezoelectric/electrostrictive body formed on the first electrode so that the volume changes with input and output of electric power, and a second electrode formed on the piezoelectric/electrostrictive body. The piezoelectric/electrostrictive body is composed of Pb(Zr1-xTix)O3 or (Li, Na, K) (Nb, Ta)O3 as a main component and contains crystals oriented along the direction of an electric field. In the actuator, the degree of orientation of the piezoelectric/electrostrictive body can be increased regardless of the orientation of the substrate on which the piezoelectric/electrostrictive body is formed.
    Type: Application
    Filed: January 23, 2009
    Publication date: July 30, 2009
    Applicant: NGK Insulators, Ltd.
    Inventors: Yukinobu YURA, Shohei Yokoyama, Nobuyuki Kobayashi, Tsutomu Nanataki
  • Publication number: 20090185971
    Abstract: A crystallographically-oriented ceramic including first regions, in which crystal nuclei remain and which contain a specific element in a predetermined concentration range and extend at least partially in a layered shape along a crystal plane, and second regions, which contain the specific element in a different concentration range from the first regions and extend at least partially in a layered shape along the crystal plane. The regions are alternately repeated, and a compositional distribution exists in a direction orthogonal to the crystal plane. In the first region, the concentration of Na is higher, the concentration of K is lower, the concentration of Nb is lower, and the concentration of Ta is higher than the second region, and in the second region, the concentration of Na is lower, the concentration of K is higher, the concentration of Nb is higher, and the concentration of Ta is lower than the first region.
    Type: Application
    Filed: February 22, 2008
    Publication date: July 23, 2009
    Applicant: NGK Insulators, Ltd.
    Inventors: Shohei Yokoyama, Nobuyuki Kobayashi, Tsutomu Nanataki
  • Patent number: 7528539
    Abstract: An electron emitter includes an emitter layer formed of a dielectric material, an upper electrode, and a lower electrode. A drive voltage is applied between the upper electrode and the lower electrode, for emitting electrons. The upper electrode is formed of scale-like conductive particles on the upper surface of the emitter layer and has a plurality of opening portions. The surfaces of overhanging portions of the opening portions that face the emitter layer are apart from the emitter layer. The overhanging portions each have such a cross-sectional shape as to be acutely pointed toward the inner edge of the opening portion, or the tip end of the overhanging portion, so that lines of electric force concentrate at the inner edge.
    Type: Grant
    Filed: June 2, 2005
    Date of Patent: May 5, 2009
    Assignee: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Kei Sato, Nobuyuki Kobayashi, Shohei Yokoyama
  • Publication number: 20080295948
    Abstract: A method for producing a crystallographically-oriented ceramic includes the steps of forming a first sheet with a thickness of 10 ?m or less containing a first inorganic material in which grain growth occurs at a first temperature or higher and a second sheet containing a second inorganic material in which grain growth occurs at a second temperature higher than the first temperature, laminating one or more each of the first and second sheets to form a laminated body, firing the laminated body at a temperature equal to or higher than the first temperature and lower than the second temperature to cause grain growth in the first inorganic material, and then firing the laminated body at a temperature equal to or higher than the second temperature to cause grain growth in the second inorganic material in the direction of a crystal plane of the first inorganic material.
    Type: Application
    Filed: January 14, 2008
    Publication date: December 4, 2008
    Applicant: NGK Insulators, Ltd.
    Inventors: Shohei Yokoyama, Nobuyuki Kobayashi, Tsutomu Nanataki
  • Publication number: 20080248277
    Abstract: A ceramic sheet is self-supported and planar and has a thickness of 10 ?m or less, wherein a surface of the sheet includes a specific crystal plane, and the number of crystal grains present in the thickness direction of the sheet at any one point is substantially one. Preferably, the aspect ratio of the crystal grains is 3 or more, and the degree of orientation measured by the Lotgering method is 30% or more. The crystal grains may be composed of an oxide represented by general formula ABO3, wherein the A site contains at least one element selected from the group consisting of Li, Na, K, Bi, and Ag, and the B site contains at least one element selected from the group consisting of Nb, Ta, and Ti. The crystal grains may be composed of an oxide having a perovskite structure and an isotropic shape.
    Type: Application
    Filed: January 15, 2008
    Publication date: October 9, 2008
    Applicant: NGK Insulators, Ltd.
    Inventors: Shohei YOKOYAMA, Nobuyuki Kobayashi, Tsutomu Nanataki, Akira Urakawa
  • Publication number: 20080206561
    Abstract: A plate-like polycrystalline particle is produced by forming inorganic particles into a self-supported, sheet-like shaped body with a predetermined thickness, firing the shaped body, and crushing and classifying the fired shaped body by passing through a mesh having openings with a predetermined size. The inorganic particles are composed of an oxide having a perovskite structure and grow into crystal grains with an isotropic and polyhedral shape. Since grain growth in the thickness direction is limited and grain growth in the surface direction of the sheet is promoted, it is possible to obtain crystal grains having a high aspect ratio and a high degree of orientation. Therefore, in the plate-like polycrystalline particle, in most parts, the number of crystal grains present in the thickness direction of the particle at any one point is one, and a high aspect ratio and a high degree of orientation are achieved.
    Type: Application
    Filed: January 22, 2008
    Publication date: August 28, 2008
    Applicant: NGK Insulators, Ltd.
    Inventors: Shohei YOKOYAMA, Nobuyuki Kobayashi, Tsutomu Nanataki
  • Publication number: 20070069622
    Abstract: An electron emitter includes an emitter layer composed of a dielectric material, a first electrode disposed onto a first surface of the emitter layer, and a second electrode disposed onto the first surface, inside, or onto a second surface opposite to the first surface of the emitter layer. A microscopic recess is disposed on a surface of the first electrode. Alternatively, an opening is disposed in the first electrode, the opening exposing the first surface of the emitter layer to the outside of the electron emitter, and a plurality of microscopic protrusions are disposed along the thickness direction of the first electrode at an inner edge of the opening.
    Type: Application
    Filed: February 22, 2006
    Publication date: March 29, 2007
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Shuichi Ozawa, Koichi Yoshino, Shohei Yokoyama
  • Publication number: 20050269929
    Abstract: An electron emitter includes an emitter layer formed of a dielectric material, an upper electrode, and a lower electrode. A drive voltage is applied between the upper electrode and the lower electrode, for emitting electrons. The upper electrode is formed of scale-like conductive particles on the upper surface of the emitter layer and has a plurality of opening portions. The surfaces of overhanging portions of the opening portions that face the emitter layer are apart from the emitter layer. The overhanging portions each have such a cross-sectional shape as to be acutely pointed toward the inner edge of the opening portion, or the tip end of the overhanging portion, so that lines of electric force concentrate at the inner edge.
    Type: Application
    Filed: June 2, 2005
    Publication date: December 8, 2005
    Applicant: NGK Insulators, Ltd.
    Inventors: Iwao Ohwada, Kei Sato, Nobuyuki Kobayashi, Shohei Yokoyama