Patents by Inventor Akira Urakawa
Akira Urakawa 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).
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Publication number: 20210203024Abstract: A coin-type secondary cell for soldering by reflow method includes a positive electrode, a negative electrode, an electrolyte layer, and a cell case. The cell case has an enclosed space in which the positive electrode, the negative electrode, and the electrolyte layer are housed. The cell case includes a positive electrode can, a negative electrode can, and a gasket. The positive electrode can and the negative electrode can have plate thicknesses of 0.075 to 0.25 mm and are different in plate thickness.Type: ApplicationFiled: March 17, 2021Publication date: July 1, 2021Applicant: NGK INSULATORS, LTD.Inventors: Yukinobu YURA, Kazuki MAEDA, Akira URAKAWA
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Publication number: 20210184241Abstract: A coin-type secondary cell for soldering by reflow method includes a porous positive electrode, a porous negative electrode, a porous separator provided between the positive electrode and the negative electrode, an electrolytic solution with which the positive electrode, the negative electrode, and the separator are impregnated, and a cell case having an enclosed space in which the positive electrode, the negative electrode, the separator, and the electrolytic solution are housed. A value obtained by dividing the amount of the electrolytic solution by the sum of the amounts of voids in the positive electrode, the negative electrode, and the separator ranges from 1.025 to 2.4.Type: ApplicationFiled: February 26, 2021Publication date: June 17, 2021Applicant: NGK INSULATORS, LTD.Inventors: Yukinobu YURA, Kazuki MAEDA, Akira URAKAWA
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Patent number: 9515347Abstract: An object of the present invention is to provide a lithium secondary battery cathode which can more improve characteristics of the battery. The cathode of the present invention includes an electroconductive cathode current collector, a plurality of plate-like particle formed of a cathode active material, and a binder containing microparticles formed of the cathode active material and being smaller than the plate-like particles. The plate-like particles are formed so as to have an aspect ratio of 4 to 50. The plate-like particles are arranged such that the particles cover the surface of the cathode current collector surface at a percent area of 85 to 98%. The binder is disposed so as to intervene between two adjacent plate-like particles.Type: GrantFiled: November 1, 2011Date of Patent: December 6, 2016Assignee: NGK Insulators, Ltd.Inventors: Shigeki Okada, Tsutomu Nanataki, Nobuyuki Kobayashi, Jun Yoshikawa, Akira Urakawa
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Patent number: 9115005Abstract: A cathode active material precursor particle, a method for producing thereof and a method for producing cathode active material for a lithium secondary battery. The cathode active material precursor particle is capable of forming a cathode active material for a lithium secondary battery including a lithium composite oxide having a layered rock salt structure through lithium incorporation. The particles are characterized by the cathode active material precursor particle being formed into a substantially spherical shape and includes therein a large number of voids in a substantially uniform manner; and the cathode active material precursor particle has: an average particle diameter D50 of 0.5 to 5 ?m; a specific surface area of 3 to 25 m2/g; and a relative tap density, which is a value obtained by dividing a tap density by a theoretical density of a material constituting the cathode active material precursor particle, of 0.25 to 0.4.Type: GrantFiled: September 13, 2012Date of Patent: August 25, 2015Assignee: NGK Insulators, Ltd.Inventors: Shigeki Okada, Ryuta Sugiura, Akira Urakawa, Kazuki Maeda, Tsutomu Nanataki
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Patent number: 9023519Abstract: The present invention relates to a cathode and a cathode active material plate for a lithium secondary battery, and the production method thereof. There is a feature of the present invention in that grooves consisting of a concave portion and having an infinite form (for example, an infinite cell-like shape) in a planar view are formed in a principal surface of the cathode active material plate.Type: GrantFiled: February 21, 2013Date of Patent: May 5, 2015Assignee: NGK Insulators, Ltd.Inventors: Shuichi Ozawa, Akira Urakawa, Shigeki Okada, Ryuta Sugiura, Tsutomu Nanataki
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Patent number: 8821765Abstract: The present invention provides a cathode active material for a lithium secondary battery containing therein an open pore having a protrusion which is formed so as to extend from the inner surface of the open pore toward the center of the open pore. Specifically, the protrusion is formed so as to extend toward the center of a virtual circle formed by approximating the shape of a cross section of the open pore to a circular shape. The protrusion is formed of the same material as the remaining portion of the cathode active material.Type: GrantFiled: August 4, 2011Date of Patent: September 2, 2014Assignee: NGK Insulators, Ltd.Inventors: Ryuta Sugiura, Akira Urakawa, Nobuyuki Kobayashi, Tsutomu Nanataki
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Patent number: 8628881Abstract: An object of the present invention is to provide a lithium secondary battery cathode which can more improve characteristics of the battery. The cathode of the present invention includes a first layer composed of a plate-like cathode active material and a second layer containing particles of the cathode active material and a binder, the second layer being joined to the first layer in a stacked state.Type: GrantFiled: November 1, 2011Date of Patent: January 14, 2014Assignee: NGK Insulators, Ltd.Inventors: Shigeki Okada, Tsutomu Nanataki, Nobuyuki Kobayashi, Jun Yoshikawa, Akira Urakawa
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Publication number: 20130252087Abstract: The present invention relates to a cathode and a cathode active material plate for a lithium secondary battery, and the production method thereof. There is a feature of the present invention in that grooves consisting of a concave portion and having an infinite form (for example, an infinite cell-like shape) in a planar view are formed in a principal surface of the cathode active material plate.Type: ApplicationFiled: February 21, 2013Publication date: September 26, 2013Applicant: NGK INSULATORS, LTD.Inventors: Shuichi OZAWA, Akira URAKAWA, Shigeki OKADA, Ryuta SUGIURA, Tsutomu NANATAKI
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Publication number: 20130071748Abstract: A cathode active material precursor particle, a method for producing thereof and a method for producing cathode active material for a lithium secondary battery. The cathode active material precursor particle is capable of forming a cathode active material for a lithium secondary battery including a lithium composite oxide having a layered rock salt structure through lithium incorporation. The particles are characterized by the cathode active material precursor particle being formed into a substantially spherical shape and includes therein a large number of voids in a substantially uniform manner; and the cathode active material precursor particle has: an average particle diameter D50 of 0.5 to 5 ?m; a specific surface area of 3 to 25 m2/g; and a relative tap density, which is a value obtained by dividing a tap density by a theoretical density of a material constituting the cathode active material precursor particle, of 0.25 to 0.4.Type: ApplicationFiled: September 13, 2012Publication date: March 21, 2013Applicant: NGK Insulators, Ltd.Inventors: Shigeki Okada, Ryuta Sugiura, Akira Urakawa, Kazuki Maeda, Tsutomu Nanataki
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Publication number: 20120121979Abstract: An object of the present invention is to provide a lithium secondary battery cathode which can more improve characteristics of the battery. The cathode of the present invention includes an electroconductive cathode current collector, a plurality of plate-like particle formed of a cathode active material, and a binder containing microparticles formed of the cathode active material and being smaller than the plate-like particles. The plate-like particles are formed so as to have an aspect ratio of 4 to 50. The plate-like particles are arranged such that the particles cover the surface of the cathode current collector surface at a percent area of 85 to 98%. The binder is disposed so as to intervene between two adjacent plate-like particles.Type: ApplicationFiled: November 1, 2011Publication date: May 17, 2012Applicant: NGK Insulators, Ltd.Inventors: Shigeki Okada, Tsutomu Nanataki, Nobuyuki Kobayashi, Jun Yoshikawa, Akira Urakawa
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Publication number: 20120121978Abstract: An object of the present invention is to provide a lithium secondary battery cathode which can more improve characteristics of the battery. The cathode of the present invention includes a first layer composed of a plate-like cathode active material and a second layer containing particles of the cathode active material and a binder, the second layer being joined to the first layer in a stacked state.Type: ApplicationFiled: November 1, 2011Publication date: May 17, 2012Applicant: NGK Insulators, Ltd.Inventors: Shigeki OKada, Tsutomu Nanataki, Nobuyuki Kobayashi, Jun Yoshikawa, Akira Urakawa
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Publication number: 20120049109Abstract: The present invention provides a cathode active material for a lithium secondary battery containing therein an open pore having a protrusion which is formed so as to extend from the inner surface of the open pore toward the center of the open pore. Specifically, the protrusion is formed so as to extend toward the center of a virtual circle formed by approximating the shape of a cross section of the open pore to a circular shape. The protrusion is formed of the same material as the remaining portion of the cathode active material.Type: ApplicationFiled: August 4, 2011Publication date: March 1, 2012Applicant: NGK Insulators, Ltd.Inventors: Ryuta SUGIURA, Akira Urakawa, Nobuyuki Kobayashi, Tsutomu Nanataki
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Publication number: 20100159325Abstract: 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: ApplicationFiled: December 22, 2009Publication date: June 24, 2010Applicant: NGK Insulators, Ltd.Inventors: Ryuta SUGIURA, Nobuyuki Kobayashi, Shohei Yokoyama, Tsutomu Nanataki, Akira Urakawa
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Publication number: 20080248277Abstract: 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: ApplicationFiled: January 15, 2008Publication date: October 9, 2008Applicant: NGK Insulators, Ltd.Inventors: Shohei YOKOYAMA, Nobuyuki Kobayashi, Tsutomu Nanataki, Akira Urakawa
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Patent number: 5770833Abstract: A laser processing method locates a processing head at a piercing start position so that the focal point of the laser beam is positioned above the workpiece surface and offset from a point right above the intended piercing point on the workpiece. While conducting irradiation with the laser beam and jetting of an assist gas, the processing head located at the piercing start position is moved simultaneously both in a direction parallel to the workpiece surface and a direction perpendicular to the workpiece surface such that the focal point approaches the piercing point.Type: GrantFiled: January 21, 1997Date of Patent: June 23, 1998Assignee: Mitsubishi Denki Kabushiki KaishaInventors: Masaru Kanaoka, Tooru Murai, Akira Urakawa
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Patent number: 4055235Abstract: A bicycle brake device for increasing the braking power to be applied to the wheel of a bicycle which has caliper type brake arms mounted on the seat stay bridge by a bolt about which the caliper arms are pivotally movable. A cage is mounted on the ends of the caliper arms and has an open end and a closed end. A brake shoe is slidably carried for axial movement in the cage through the open end and has a front end and a rear end oriented with the open and closed end respectively of the cage. A brake block is carried in the brake shoe and has a surface for engaging the rim to apply friction forces for braking action. A cam is mounted at the front end of the brake shoe for engaging the seat stay upon forward sliding movement of the brake shoe in the cage as a result of friction forces between the brake block and the rim when the block engages the rim.Type: GrantFiled: July 8, 1976Date of Patent: October 25, 1977Assignee: Nichibei Fuji Cycle Co., Ltd.Inventors: Hiroshi Tanaka, Noriyuki Ogisu, Akira Urakawa