Patents by Inventor Akihisa Kajiyama

Akihisa Kajiyama 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: 9293235
    Abstract: According to the present invention, there are provided lithium titanate particles which exhibit an excellent initial discharge capacity and an enhanced high-efficiency discharge capacity retention rate as an active substance for non-aqueous electrolyte secondary batteries and a process for producing the lithium titanate particles, and Mg-containing lithium titanate particles.
    Type: Grant
    Filed: August 29, 2011
    Date of Patent: March 22, 2016
    Assignee: TODA KOGYO CORPORATION
    Inventors: Akinori Yamamoto, Tomoko Okita, Hiroshi Yamamoto, Kohji Mori, Kazumichi Koga, Akihisa Kajiyama
  • Publication number: 20150037677
    Abstract: The present invention relates to positive electrode active substance particles for non-aqueous electrolyte secondary batteries, comprising an oxide having a spinel structure and comprising at least Li and Mn as main components and an oxide comprising at least Li and Zr, in which the oxide comprising at least Li and Zr forms a mixed phase comprising two or more phases, and a content of the oxide comprising at least Li and Zr in the positive electrode active substance particles is 0.1 to 4% by weight. The present invention provides positive electrode active substance particles for non-aqueous electrolyte secondary batteries which are excellent in high-temperature characteristics and a process for producing the positive electrode active substance particles, and a non-aqueous electrolyte secondary battery.
    Type: Application
    Filed: February 22, 2013
    Publication date: February 5, 2015
    Applicant: TODA KOGYO CORP.
    Inventors: Kazumichi Koga, Ryuta Masaki, Akihisa Kajiyama, Hiroaki Masukuni
  • Publication number: 20150024273
    Abstract: The present invention relates to lithium composite oxide particles which can be produced by mixing nickel-cobalt-manganese-based compound particles, a zirconium raw material and a lithium raw material with each other and then calcining the resulting mixture, and comprise a Zr compound that is allowed to be present on a surface thereof, in which the Zr compound is represented by the chemical formula: Lix(Zr1-yAy)Oz wherein x, y and z are 2.0?x?8.0; 0?y?1.0; and 2.0?z?6.0, respectively, and a content of Zr in the lithium composite oxide particles is 0.05 to 1.0% by weight. By using the lithium composite oxide particles as a positive electrode active substance, it is possible to produce a lithium ion secondary battery that has a low electric resistance at a high temperature, and is excellent in cycle characteristic at a high temperature as well as high-temperature rate characteristic.
    Type: Application
    Filed: March 14, 2013
    Publication date: January 22, 2015
    Inventors: Minoru Yamazaki, Osamu Sasaki, Shoichi Fujino, Hideharu Mitsui, Takayuki Yamamura, Kunihiro Uramatsu, Akihisa Kajiyama, Ryuta Masaki
  • Patent number: 8821766
    Abstract: The present invention aims at providing lithium manganate having a high output and an excellent high-temperature stability. The above aim can be achieved by lithium manganate particles having a primary particle diameter of not less than 1 ?m and an average particle diameter (D50) of kinetic particles of not less than 1 ?m and not more than 10 ?m, which are substantially in the form of single crystal particles and have a composition represented by the following chemical formula: Li1+xMn2-x-yYyO4 in which Y is at least one element selected from the group consisting of Al, Mg and Co; x and y satisfy 0.03?x?0.15 and 0.05?y?0.20, respectively, wherein the Y element is uniformly dispersed within the respective particles, and an intensity ratio of I(400)/I(111) thereof is not less than 33% and an intensity ratio of I(440)/I(111) thereof is not less than 16%.
    Type: Grant
    Filed: March 7, 2013
    Date of Patent: September 2, 2014
    Assignee: Toda Kogyo Corporation
    Inventors: Masayuki Uegami, Akihisa Kajiyama, Kazutoshi Ishizaki, Hideaki Sadamura
  • Publication number: 20140034872
    Abstract: The present invention provides a precursor of positive electrode active substance particles for non-aqueous electrolyte secondary batteries which have a high discharge voltage and a high discharge capacity, hardly suffer from side reactions with an electrolyte solution, and are excellent in cycle characteristics, positive electrode active substance particles for non-aqueous electrolyte secondary batteries, and processes for producing these particles, and a non-aqueous electrolyte secondary battery.
    Type: Application
    Filed: December 26, 2011
    Publication date: February 6, 2014
    Applicant: Toda Kogyo Corporation
    Inventors: Hiroyasu Watanabe, Daisuke Morita, Manabu Yamamoto, Kazumichi Koga, Akihisa Kajiyama, Hiroaki Masukuni, Hideaki Sadamura, Ryuta Masaki, Kazutoshi Matsumoto
  • Publication number: 20130330626
    Abstract: The present invention relates to Li—Ni-based composite oxide particles comprising Mn, and Co and/or Al, wherein Co and Al are uniformly dispersed within the particles, and Mn is present with a gradient of its concentration in a radial direction of the respective particles such that a concentration of Mn on a surface of the respective particles is higher than that at a central portion thereof. The Li—Ni-based composite oxide particles can be produced by allowing an oxide and a hydroxide comprising Mn to mechanically adhere to Li—Ni-based oxide comprising Co and/or Al; and then heat-treating the obtained material at a temperature of not lower than 400° C. and not higher than 1,000° C. The Li—Ni-based composite oxide particles of the present invention are improved in thermal stability and alkalinity.
    Type: Application
    Filed: August 15, 2013
    Publication date: December 12, 2013
    Applicant: TODA KOGYO CORPORATION
    Inventors: Akihisa KAJIYAMA, Kazuhiko KIKUYA, Teruaki SANTOKI, Osamu SASAKI, Satoshi NAKAMURA, Taiki IMAHASHI, Hideaki SADAMURA
  • Patent number: 8592085
    Abstract: The present invention relates to nickel-cobalt-manganese-based compound particles which have a volume-based average secondary particle diameter (D50) of 3.0 to 25.0 ?m, wherein the volume-based average secondary particle diameter (D50) and a half value width (W) of the peak in volume-based particle size distribution of secondary particles thereof satisfy the relational formula: W?0.4×D50, and can be produced by dropping a metal salt-containing solution and an alkali solution to an alkali solution at the same time, followed by subjecting the obtained reaction solution to neutralization and precipitation reaction. The nickel-cobalt-manganese-based compound particles according to the present invention have a uniform particle size, a less content of very fine particles, a high crystallinity and a large primary particle diameter, and therefore are useful as a precursor of a positive electrode active substance used in a non-aqueous electrolyte secondary battery.
    Type: Grant
    Filed: October 21, 2010
    Date of Patent: November 26, 2013
    Assignee: Toda Kogyo Corporation
    Inventors: Masashi Kobino, Katsuhiro Fujita, Shoichi Fujino, Akihisa Kajiyama, Ryuta Masaki, Daisuke Morita, Takayuki Yamamura, Tetsuya Kodaira, Minoru Yamasaki, Seiji Okazaki, Toshiaki Hiramoto, Akino Sato, Wataru Oda, Kenji Okinaka
  • Patent number: 8546018
    Abstract: The present invention relates to Li—Ni-based composite oxide particles comprising Mn, and Co and/or Al, wherein Co and Al are uniformly dispersed within the particles, and Mn is present with a gradient of its concentration in a radial direction of the respective particles such that a concentration of Mn on a surface of the respective particles is higher than that at a central portion thereof. The Li—Ni-based composite oxide particles can be produced by allowing an oxide and a hydroxide comprising Mn to mechanically adhere to Li—Ni-based oxide comprising Co and/or Al; and then heat-treating the obtained material at a temperature of not lower than 400° C. and not higher than 1,000° C. The Li—Ni-based composite oxide particles of the present invention are improved in thermal stability and alkalinity.
    Type: Grant
    Filed: November 11, 2008
    Date of Patent: October 1, 2013
    Assignee: Toda Kogyo Corporation
    Inventors: Akihisa Kajiyama, Kazuhiko Kikuya, Teruaki Santoki, Osamu Sasaki, Satoshi Nakamura, Taiki Imahashi, Hideaki Sadamura
  • Publication number: 20130244114
    Abstract: According to the present invention, there are provided lithium titanate particles which exhibit an excellent initial discharge capacity and an enhanced high-efficiency discharge capacity retention rate as an active substance for non-aqueous electrolyte secondary batteries and a process for producing the lithium titanate particles, and Mg-containing lithium titanate particles. The present invention relates to lithium titanate particles with a spinel structure comprising TiO2 in an amount of not more than 1.
    Type: Application
    Filed: August 29, 2011
    Publication date: September 19, 2013
    Applicant: Toda Kogyo Corporation
    Inventors: Akinori Yamamoto, Tomoko Okita, Hiroshi Yamamoto, Kohji Mori, Kazumichi Koga, Akihisa Kajiyama
  • Patent number: 8440113
    Abstract: The present invention aims at providing lithium manganate having a high output and an excellent high-temperature stability. The above aim can be achieved by lithium manganate particles having a primary particle diameter of not less than 1 ?m and an average particle diameter (D50) of kinetic particles of not less than 1 ?m and not more than 10 ?m, which are substantially in the form of single crystal particles and have a composition represented by the following chemical formula: Li1+xMn2?x?yYyO4 in which Y is at least one element selected from the group consisting of Al, Mg and Co; x and y satisfy 0.03?x?0.15 and 0.05?y?0.20, respectively, wherein the Y element is uniformly dispersed within the respective particles, and an intensity ratio of I(400)/I(111) thereof is not less than 33% and an intensity ratio of I(440)/I(111) thereof is not less than 16%.
    Type: Grant
    Filed: March 27, 2008
    Date of Patent: May 14, 2013
    Assignee: Toda Kogyo Corporation
    Inventors: Masayuki Uegami, Akihisa Kajiyama, Kazutoshi Ishizaki, Hideaki Sadamura
  • Publication number: 20130045421
    Abstract: The present invention relates to nickel-cobalt-manganese-based compound particles which have a volume-based average secondary particle diameter (D50) of 3.0 to 25.0 ?m, wherein the volume-based average secondary particle diameter (D50) and a half value width (W) of the peak in volume-based particle size distribution of secondary particles thereof satisfy the relational formula: W?0.4×D50, and can be produced by dropping a metal salt-containing solution and an alkali solution to an alkali solution at the same time, followed by subjecting the obtained reaction solution to neutralization and precipitation reaction. The nickel-cobalt-manganese-based compound particles according to the present invention have a uniform particle size, a less content of very fine particles, a high crystallinity and a large primary particle diameter, and therefore are useful as a precursor of a positive electrode active substance used in a non-aqueous electrolyte secondary battery.
    Type: Application
    Filed: October 21, 2010
    Publication date: February 21, 2013
    Inventors: Masashi Kobino, Katsuhiro Fujita, Shoichi Fujino, Akihisa Kajiyama, Ryuta Masaki, Daisuke Morita, Takayuki Yamamura, Tetsuya Kodaira, Minoru Yamasaki, Seiji Okazaki, Toshiaki Hiramoto, Akino Sato, Wataru Oda, Kenji Okinaka
  • Publication number: 20120196185
    Abstract: The present invention relates to a positive electrode active substance for non-aqueous electrolyte secondary batteries which comprises particles comprising a polyanionic compound and carbon, and a lipophilic treatment agent with which the respective particles are coated, wherein the positive electrode active substance has an average particle diameter of 1 to 50 ?m. The positive electrode active substance preferably has an oil absorption of not more than 20 mL/100 g. The positive electrode active substance according to the present invention exhibits a good compatibility with a resin and is excellent in packing property and dispersibility in the resin, and therefore can provide an electrode sheet in which the positive electrode active substance is filled with a high packing density.
    Type: Application
    Filed: July 27, 2010
    Publication date: August 2, 2012
    Inventors: Yoshiteru Kono, Kenji Ogisu, Toshiyuki Hakata, Yuji Mishima, Katsuji Iwami, Masayuki Yokota, Minoru Yamasaki, Akihisa Kajiyama, Hideaki Sadamura
  • Publication number: 20100316910
    Abstract: The present invention relates to Li—Ni-based composite oxide particles comprising Mn, and Co and/or Al, wherein Co and Al are uniformly dispersed within the particles, and Mn is present with a gradient of its concentration in a radial direction of the respective particles such that a concentration of Mn on a surface of the respective particles is higher than that at a central portion thereof. The Li—Ni-based composite oxide particles can be produced by allowing an oxide and a hydroxide comprising Mn to mechanically adhere to Li—Ni-based oxide comprising Co and/or Al; and then heat-treating the obtained material at a temperature of not lower than 400° C. and not higher than 1,000° C. The Li—Ni-based composite oxide particles of the present invention are improved in thermal stability and alkalinity.
    Type: Application
    Filed: November 11, 2008
    Publication date: December 16, 2010
    Inventors: Akihisa Kajiyama, Kazuhiko Kikuya, Teruaki Santoki, Osamu Sasaki, Satoshi Nakamura, Taiki Imahashi, Hideaki Sadamura
  • Publication number: 20100288969
    Abstract: The present invention relates to lithium manganate particles having a primary particle diameter of not less than 1 ?m and an average particle diameter (D50) of not less than 2 ?m and not more than 10 ?m as measured by a particle size distribution meter, and forming particles having substantially a single phase, which have a composition represented by the following chemical formula: Li1+xMn2?x?yY1yO4+Y2 where Y1 is at least one element selected from the group consisting of Ni, Co, Mg, Fe, Al, Cr and Ti; Y2 is at least one element constituting a sintering aid having a melting point of not higher than 800° C., x and y satisfy 0.03?x?0.15 and 0.05?y?0.20, respectively, and Y2 is present in an amount of 0.1 to 2.5 mol % based on Mn; the Y1 element being dispersed within the respective particles, and an X-ray diffraction intensity ratio of I(400)/I(111) of the particles being not less than 38% and an X-ray diffraction intensity ratio of I(440)/I(111) thereof being not less than 18%.
    Type: Application
    Filed: November 12, 2008
    Publication date: November 18, 2010
    Inventors: Kazumichi Koga, Masayuki Uegami, Akihisa Kajiyama, Kazutoshi Ishizaki, Hideaki Sadamura
  • Publication number: 20100207059
    Abstract: The present invention aims at providing lithium manganate having a high output and an excellent high-temperature stability. The above aim can be achieved by lithium manganate particles having a primary particle diameter of not less than 1 ?m and an average particle diameter (D50) of kinetic particles of not less than 1 ?m and not more than 10 ?m, which are substantially in the form of single crystal particles and have a composition represented by the following chemical formula: Li1+xMn2?x?yYyO4 in which Y is at least one element selected from the group consisting of Al, Mg and Co; x and y satisfy 0.03?x?0.15 and 0.05?y?0.20, respectively, wherein the Y element is uniformly dispersed within the respective particles, and an intensity ratio of I(400)/I(111) thereof is not less than 33% and an intensity ratio of I(440)/I(111) thereof is not less than 16%.
    Type: Application
    Filed: March 27, 2008
    Publication date: August 19, 2010
    Inventors: Masayuki Uegami, Akihisa Kajiyama, Kazutoshi Ishizaki, Hideaki Sadamura
  • Publication number: 20020142219
    Abstract: Provided is a lithium iron thiophosphate compound represented by a general formula: Li2xFe1-xPS3 wherein x is more than 0 and less than 1. This compound provides a lithium battery having high out put as well as high energy density when used as an electrode active material.
    Type: Application
    Filed: March 18, 2002
    Publication date: October 3, 2002
    Applicant: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Kazunori Takada, Shigeo Kondo, Mamoru Watanabe, Masaru Kouguchi, Akihisa Kajiyama, Taro Inada
  • Publication number: 20020098146
    Abstract: A lamellar sodium-cobalt-manganese oxide represented by the general formula NaxCoyMn1−yO2 (where 0.6≦x≦0.8, 0.4≦y≦0.6) is disclosed, which is obtained by the steps of: mixing a sodium salt, a cobalt salt and a manganese salt in an aqueous solution state so as to be a molar ratio of sodium, cobalt and manganese of x: y: 1−y (where 0.6≦x≦0.8, 0.4≦y≦0.6) and drying the obtained mixture, sintering the obtained dried body in an oxygen-containing gas at 700 to 900° C., and quenching the sintered body from a temperature between 700° C. and 800° C. The lamellar sodium-cobalt manganese oxide of the present invention has a uniform composition and a single crystal structure, which is useful as an electrode active material for a lithium ion secondary battery.
    Type: Application
    Filed: November 27, 2001
    Publication date: July 25, 2002
    Applicant: NATIONAL INSTITUTE FOR MATERIALS SCIENCE
    Inventors: Kazunori Takada, Shigeo Kondo, Mamoru Watanabe, Masaru Kouguchi, Akihisa Kajiyama, Taro Inada
  • Patent number: 6398977
    Abstract: The present invention provides a hollow shape strontium iron oxide particle powder. Not only is the particle powder high in safety and excellent in workability, but exhibits a large dielectric constant when formed into an artificial dielectric material utilizing electrical conduction by being dispersed in an organic medium such as a rubber.
    Type: Grant
    Filed: April 11, 2000
    Date of Patent: June 4, 2002
    Assignee: Toda Kogyo Corporation
    Inventors: Tatsuya Nakamura, Yoji Okano, Akihisa Kajiyama
  • Patent number: 6337132
    Abstract: The present invention provides a lithium nickel-layered rock salt-type oxide particle powder, a lithium cobalt-layered rock salt-type oxide particle powder or a particle powder of a solid solution of these layered rock salt-type oxides, wherein the surface of the particle is rendered hydrophobic by coating it with a coupling agent having both a hydrophobic group and a hydrophilic group. The layered rock salt-type oxide particle powder is free of an adverse effect caused by adsorbed water because of less amount of water adsorbed on the surface of the particle powder, high in electrochemical charging and discharging capacities, low in cycle deterioration, so that it is especially useful as a positive electrode active material in a lithium battery.
    Type: Grant
    Filed: March 30, 2000
    Date of Patent: January 8, 2002
    Assignee: Toda Kogyo Corporation
    Inventors: Akihisa Kajiyama, Tatsuya Nakamura
  • Patent number: 6103213
    Abstract: A process for producing lithium-cobalt oxide, comprises: mixing cobalt oxide having a BET specific surface area of 30 to 200 m.sup.2 /g or an average particle size of not more than 0.1 .mu.m, with a lithium compound; and calcining the obtained mixture at a temperature of 500 to 850.degree. C. Such a process for producing lithium-cobalt oxide particles is useful especially as a cathode active substance for lithium ion batteries, which particles can be produced by calcination in a short time, and have a narrow particle size distribution and a uniform small particle size.
    Type: Grant
    Filed: March 23, 1998
    Date of Patent: August 15, 2000
    Assignee: Toda Kogyo Corporation
    Inventors: Tatsuya Nakamura, Hideaki Sadamura, Mitsuaki Hatatani, Akihisa Kajiyama, Yoshiro Okuda