Patents by Inventor Takuya Miwa

Takuya Miwa 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: 20150099161
    Abstract: To achieve a power storage unit that can be repeatedly bent without a large decrease in charge and discharge capacity. In the flexible power storage unit, the content of a binder in an active material layer containing an active material is greater than or equal to 1 wt % and less than or equal to 10 wt %, preferably greater than or equal to 2 wt % and less than or equal to 8 wt %, and more preferably greater than or equal to 3 wt % and less than or equal to 5 wt %.
    Type: Application
    Filed: September 19, 2014
    Publication date: April 9, 2015
    Inventors: Aya HITOTSUYANAGI, Teppei OGUNI, Takuya MIWA, Hiroyuki MIYAKE
  • Patent number: 8865270
    Abstract: The power extraction efficiency of a nonaqueous electrolyte secondary battery such as a lithium ion battery is improved. A material having magnetic susceptibility anisotropy such as an olivine type oxide including a transition metal element is used for active material particles. The active material particles and an electrolyte solution are mixed to form a slurry. The slurry is applied to a current collector, and then the current collector is left in a magnetic field. Thus, the active material particles are oriented. With the use of active material particles oriented in such a manner, the power extraction efficiency can be improved.
    Type: Grant
    Filed: December 29, 2011
    Date of Patent: October 21, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Mayumi Mikami, Takuya Miwa, Kuniharu Nomoto, Takeshi Osada
  • Publication number: 20140295261
    Abstract: An object is to provide an electrochemical device in which lithium deposition and reduction in battery capacity can be inhibited even when the concentration of a lithium salt in an electrolytic solution is lower than 1.0 M. Lithium deposition can be inhibited and lithium whiskers can be dissolved by applying an inversion pulse current for a short time more than once in a charging period of a secondary battery which deteriorates. By applying the inversion pulse current more than once, deterioration of a lithium-ion secondary battery due to repeated charging can be suppressed even when it is a secondary battery in which the concentration of a lithium salt in an electrolytic solution is lower than 1.0 M and therefore lithium is easily deposited.
    Type: Application
    Filed: March 20, 2014
    Publication date: October 2, 2014
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Hiroyuki MIYAKE, Teppei OGUNI, Tatsuya TAKAHASHI, Takuya MIWA, Aya HITOTSUYANAGI
  • Publication number: 20140166946
    Abstract: At least one of an aqueous solution A containing lithium, an aqueous solution B containing iron, manganese, cobalt, or nickel, and an aqueous solution C containing a phosphoric acid includes graphene oxide. The aqueous solution A is dripped into the aqueous solution C, so that a mixed solution E including a precipitate D is prepared. The mixed solution E is dripped into the aqueous solution B, so that a mixed solution G including a precipitate F is prepared. The mixed solution G is subjected to heat treatment in a pressurized atmosphere, so that a mixed solution H is prepared, and the mixed solution H is then filtered. Thus, particles of a compound containing lithium and oxygen which have a small size are obtained.
    Type: Application
    Filed: February 12, 2014
    Publication date: June 19, 2014
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takuya MIWA, Kuniharu Nomoto, Nobuhiro Inoue
  • Patent number: 8715525
    Abstract: One object is to provide a manufacturing method of an electrode material with which a characteristic of a power storage device can be improved. In a manufacturing method of an electrode material comprising a compound represented by a general formula A2-aMSiO4 (A represents an alkali metal, M represents a transition metal, and a represents 0?a<2), a mixed material is formed by mixing a compound that is a supply source of A, a compound that is a supply source of M, and a compound that is a supply source of Si; a flux is mixed into the mixed material after the mixed material is subjected to a heat treatment at a temperature of 400° C. or lower and pulverized; and the mixed material into which the flux is mixed is subjected to a heat treatment at a temperature of 700° C. or lower in an inert gas atmosphere.
    Type: Grant
    Filed: June 28, 2011
    Date of Patent: May 6, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Masaki Yamakaji, Takuya Miwa
  • Patent number: 8685570
    Abstract: At least one of an aqueous solution A containing lithium, an aqueous solution B containing iron, manganese, cobalt, or nickel, and an aqueous solution C containing a phosphoric acid includes graphene oxide. The aqueous solution A is dripped into the aqueous solution C, so that a mixed solution E including a precipitate D is prepared. The mixed solution E is dripped into the aqueous solution B, so that a mixed solution G including a precipitate F is prepared. The mixed solution G is subjected to heat treatment in a pressurized atmosphere, so that a mixed solution H is prepared, and the mixed solution H is then filtered. Thus, particles of a compound containing lithium and oxygen which have a small size are obtained.
    Type: Grant
    Filed: June 21, 2013
    Date of Patent: April 1, 2014
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Takuya Miwa, Kuniharu Nomoto, Nobuhiro Inoue
  • Publication number: 20130283603
    Abstract: At least one of an aqueous solution A containing lithium, an aqueous solution B containing iron, manganese, cobalt, or nickel, and an aqueous solution C containing a phosphoric acid includes graphene oxide. The aqueous solution A is dripped into the aqueous solution C, so that a mixed solution E including a precipitate D is prepared. The mixed solution E is dripped into the aqueous solution B, so that a mixed solution G including a precipitate F is prepared. The mixed solution G is subjected to heat treatment in a pressurized atmosphere, so that a mixed solution H is prepared, and the mixed solution H is then filtered. Thus, particles of a compound containing lithium and oxygen which have a small size are obtained.
    Type: Application
    Filed: June 21, 2013
    Publication date: October 31, 2013
    Inventors: Takuya MIWA, Kuniharu Nomoto, Nobuhiro Inoue
  • Patent number: 8470477
    Abstract: At least one of an aqueous solution A containing lithium, an aqueous solution B containing iron, manganese, cobalt, or nickel, and an aqueous solution C containing a phosphoric acid includes graphene oxide. The aqueous solution A is dripped into the aqueous solution C, so that a mixed solution E including a precipitate D is prepared. The mixed solution E is dripped into the aqueous solution B, so that a mixed solution G including a precipitate F is prepared. The mixed solution G is subjected to heat treatment in a pressurized atmosphere, so that a mixed solution H is prepared, and the mixed solution H is then filtered. Thus, particles of a compound containing lithium and oxygen which have a small size are obtained.
    Type: Grant
    Filed: August 27, 2012
    Date of Patent: June 25, 2013
    Assignee: Semiconductor Energy Laboratory Co., Ltd.
    Inventors: Takuya Miwa, Kuniharu Nomoto, Nobuhiro Inoue
  • Publication number: 20130065120
    Abstract: Occlusion and release of lithium ion are likely to one-dimensionally occur in the b-axis direction of a crystal in a lithium-containing composite oxide having an olivine structure. Thus, a positive electrode in which the b-axes of lithium-containing composite oxide single crystals are oriented vertically to a surface of a positive electrode current collector is provided. The lithium-containing composite oxide particles are mixed with graphene oxide and then pressure is applied thereto, whereby the rectangular parallelepiped or substantially rectangular parallelepiped particles are likely to slip. In addition, in the case where the rectangular parallelepiped or substantially rectangular parallelepiped particles whose length in the b-axis direction is shorter than those in the a-axis direction and the c-axis direction are used, when pressure is applied in one direction, the b-axes can be oriented in the one direction.
    Type: Application
    Filed: September 4, 2012
    Publication date: March 14, 2013
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takuya MIWA, Nobuhiro INOUE, Kuniharu NOMOTO, Junpei MOMO
  • Publication number: 20130047422
    Abstract: An object is to reduce variation in shape of crystals that are to be manufactured. Raw materials are each weighed, solutions containing the respective raw materials are formed in an environment where an oxygen concentration is lower than that in air, the solutions containing the respective raw materials are mixed in an environment where an oxygen concentration is lower than that in air to form a mixture solution, and with use of the mixture solution, a composite oxide is formed by a hydrothermal method.
    Type: Application
    Filed: August 17, 2012
    Publication date: February 28, 2013
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takuya Miwa, Kuniharu Nomoto, Junpei Momo
  • Publication number: 20130047423
    Abstract: At least one of an aqueous solution A containing lithium, an aqueous solution B containing iron, manganese, cobalt, or nickel, and an aqueous solution C containing a phosphoric acid includes graphene oxide. The aqueous solution A is dripped into the aqueous solution C, so that a mixed solution E including a precipitate D is prepared. The mixed solution E is dripped into the aqueous solution B, so that a mixed solution G including a precipitate F is prepared. The mixed solution G is subjected to heat treatment in a pressurized atmosphere, so that a mixed solution H is prepared, and the mixed solution H is then filtered. Thus, particles of a compound containing lithium and oxygen which have a small size are obtained.
    Type: Application
    Filed: August 27, 2012
    Publication date: February 28, 2013
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takuya MIWA, Kuniharu Nomoto, Nobuhiro Inoue
  • Publication number: 20130047915
    Abstract: An object is to reduce variation in shape of crystals that are to be formed. Solutions containing respective raw materials are made in an environment where an oxygen concentration is lower than that in air, the solutions containing the respective raw materials are mixed in an environment where an oxygen concentration is lower than that in air to form a mixture solution, and with use of the mixture solution, a composite oxide is formed by a hydrothermal method.
    Type: Application
    Filed: August 17, 2012
    Publication date: February 28, 2013
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takuya MIWA, Kuniharu NOMOTO, Junpei MOMO
  • Publication number: 20120177842
    Abstract: The power extraction efficiency of a nonaqueous electrolyte secondary battery such as a lithium ion battery is improved. A material having magnetic susceptibility anisotropy such as an olivine type oxide including a transition metal element is used for active material particles. The active material particles and an electrolyte solution are mixed to form a slurry. The slurry is applied to a current collector, and then the current collector is left in a magnetic field. Thus, the active material particles are oriented. With the use of active material particles oriented in such a manner, the power extraction efficiency can be improved.
    Type: Application
    Filed: December 29, 2011
    Publication date: July 12, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Mayumi MIKAMI, Takuya Miwa, Kuniharu Nomoto, Takeshi Osada
  • Publication number: 20120088156
    Abstract: An energy storage device having high capacity per weight or volume and a positive electrode active material for the energy storage device are manufactured. A surface of a main material included in the positive electrode active material for the energy storage device is coated with two-dimensional carbon. The main material included in the positive electrode active material is coated with a highly conductive material which has a structure expanding two-dimensionally and whose thickness is ignorable, whereby the amount of carbon coating can be reduced and an energy storage device having capacity close to theoretical capacity can be obtained even when a conduction auxiliary agent is not used or the amount of the conduction auxiliary agent is extremely small. Accordingly, the amount of carbon coating in a positive electrode and the volume of the conduction auxiliary agent can be reduced; consequently, the volume of the positive electrode can be reduced.
    Type: Application
    Filed: September 29, 2011
    Publication date: April 12, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Kuniharu NOMOTO, Takuya MIWA, Masaki YAMAKAJI, Takahiro KAWAKAMI
  • Publication number: 20120088151
    Abstract: A positive-electrode active material with improved electrical conductivity, and a power storage device using the material are provided. A positive-electrode active material with large capacity, and a power storage device using the material are provided. A core including lithium metal oxide is used as a core of a main material of the positive-electrode active material, and one to ten pieces of graphene is used as a covering layer for the core. A hole is provided for graphene, whereby transmission of a lithium ion is facilitated, resulting in improvement of use efficiency of current.
    Type: Application
    Filed: September 23, 2011
    Publication date: April 12, 2012
    Inventors: Shunpei Yamazaki, Tamae Moriwaka, Takuya Hirohashi, Kuniharu Nomoto, Takuya Miwa
  • Publication number: 20120001120
    Abstract: One object is to provide a manufacturing method of an electrode material with which a characteristic of a power storage device can be improved. Another object is to provide a power storage device to which the above-mentioned electrode material is applied, and an application mode thereof. In a manufacturing method of an electrode material comprising a compound represented by a general formula A2-aMSiO4 (A represents an alkali metal, M represents a transition metal, and a represents 0?a<2), a mixed material is formed by mixing a compound that is a supply source of A of the general formula, a compound that is a supply source of M of the general formula, and a compound that is a supply source of Si of the general formula; a flux is mixed into the mixed material after the mixed material is subjected to a heat treatment at a temperature of 400° C. or lower and pulverized; and the mixed material into which the flux is mixed is subjected to a heat treatment at a temperature of 700° C.
    Type: Application
    Filed: June 28, 2011
    Publication date: January 5, 2012
    Inventors: Masaki Yamakaji, Takuya Miwa
  • Publication number: 20120003139
    Abstract: It is an object to provide a material for an electrode with improved electron conductivity and a power storage device using the material for an electrode. In a process for manufacturing a material for an electrode including a lithium phosphate compound represented by a general formula LiMPO4 having an olivine structure or a lithium silicate compound represented by a general formula Li2MSiO4 having an olivine structure, a metal element having a valence different from that of a metal element represented by M is added. The metal element having a different valence serves as a carrier generation source in the material for an electrode, whereby the electron conductivity of the material for an electrode is improved. By using the material for an electrode with improved electron conductivity as a positive electrode active material, a power storage device with larger discharge capacity is provided.
    Type: Application
    Filed: June 6, 2011
    Publication date: January 5, 2012
    Applicant: SEMICONDUCTOR ENERGY LABORATORY CO., LTD.
    Inventors: Takahiro KAWAKAMI, Takuya MIWA
  • Patent number: 6461788
    Abstract: Disclosed herein are polymerizable compounds represented by the following formula (1): wherein R1 to R9 each independently represent a hydrogen atom, a silyl group, a cyano group, a hydroxyl group, a halogen atom or a monovalent nonpolymerizable organic substituent group, and A represents a polymerizable group having a carbon-carbon double bond; polymers obtained by singly polymerizing the polymerizable compounds or copolymerizing them with copolymerizable compounds; and resist compositions comprising the polymers. These polymers are useful as base polymers for resist materials for an exposure light source of a short wavelength.
    Type: Grant
    Filed: August 15, 2000
    Date of Patent: October 8, 2002
    Assignee: Maruzen Petrochemical Co., Ltd.
    Inventors: Takuya Miwa, Nobuyuki Oka, Masao Kaneko
  • Patent number: 6462158
    Abstract: Disclosed herein are polymerizable compounds represented by the following formula (1): wherein one of R1 and R2 represents an alkyl group, which has 1 to 4 carbon atoms and is other than a tert-butyl group, and the other represents a hydrogen atom or an alkyl group which has 1 to 4 carbon atoms and is other than a tert-butyl group, R3 to R9 each independently represent a hydrogen atom, a silyl group, a cyano group, a hydroxyl group, a halogen atom or a monovalent nonpolymerizable organic substituent group, and A represents a polymerizable group having a carbon-carbon double bond; polymers obtained by singly polymerizing the polymerizable compounds or copolymerizing them with copolymerizable compounds; and resist compositions comprising the polymers. These polymers are useful as base polymers for resist materials for an exposure light source of a short wavelength.
    Type: Grant
    Filed: August 16, 2000
    Date of Patent: October 8, 2002
    Assignee: Maruzen Petrochemical Co., Ltd.
    Inventors: Takuya Miwa, Nobuyuki Oka, Masao Kaneko