Patents by Inventor Naoshi Saito

Naoshi Saito 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: 7270797
    Abstract: To provide a process for producing a lithium-cobalt composite oxide for a positive electrode of a lithium secondary battery excellent in volume capacity density, safety, charge and discharge cyclic durability, press density and productivity, by using in expensive cobalt hydroxide and lithium carbonate. A mixture having a cobalt hydroxide powder and a lithium carbonate powder mixed so that the atomic ratio of lithium/cobalt would be from 0.98 to 1.01, is fired in an oxygen-containing atmosphere at from 250 to 700° C., and the fired product is further fired in an oxygen-containing atmosphere at from 850 to 1,050° C., or such a mixture is heated at a temperature-raising rate of at most 4° C./min in a range from 250 to 600° C. and fired in an oxygen-containing atmosphere at from 850 to 1,050° C.
    Type: Grant
    Filed: May 13, 2005
    Date of Patent: September 18, 2007
    Assignee: Seimi Chemical Co., Ltd.
    Inventors: Manabu Suhara, Naoshi Saito, Kazushige Horichi, Koji Tatsumi
  • Patent number: 7238769
    Abstract: The present invention provides a method for joining liquid-crystalline polyester resin composition parts, characterized in that the melting point of the liquid crystalline polyester resin measured by differential scanning calorimeter is 190-250° C. and that the parts are jointed by means of welding. By using the method of the present invention, jointed articles with sufficient joint strength are provided with accuracy.
    Type: Grant
    Filed: May 10, 2005
    Date of Patent: July 3, 2007
    Assignee: Kabushiki Kaisha Ueno Seiyaku Oyo Kenkyujo
    Inventors: Masaya Kitayama, Naoshi Saito
  • Publication number: 20070117014
    Abstract: It is to provide a cathode active material for a lithium ion secondary battery, which has high safety, a high discharge voltage, a large capacity and excellent cyclic durability, and a process for producing it. A cathode active material for a lithium secondary battery, characterized by comprising a particulate lithium cobalt composite oxide represented by the formula LiaCobAlcMgdAeOfFg??(1) (wherein A is Ti, Nb or Ta, O.90?a?1.10, 0.97?b?1.00, 0.000l?c?0.02, 0.000l?d?0.02, 0.000l?e?0.01, 1.98?f?2.02, 0?g?0.02, and 0.0003?c+d+e?0.03).
    Type: Application
    Filed: January 19, 2007
    Publication date: May 24, 2007
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Naoshi SAITO, Kazushige Horichi, Megumi Uchida, Takeshi Kawasato, Manabu Suhara
  • Publication number: 20070099087
    Abstract: It is to provide a cathode active material powder for a positive electrode for a lithium secondary battery, which has a large volume capacity density, high safety and excellent durability for charge and discharge cycles. A cathode active material powder for a lithium secondary battery characterized by comprising a first composite oxide powder represented by the formula (1) LipQxMyOzFa (wherein Q is Co or Mn, M is aluminum or an alkaline earth metal element or a transition metal element other than Q, provided that when Q is Co, 0.9?p?1.1, 0.980?x?1.000, 0?y?0.02, 1.9?z?2.1, x+y=1, and 0?a?0.02, and when Q is Mn, 1?p?1.3, x=2?y, 0?y?0.05, z=4, and a=0), having an average particle size D50 of from 5 to 30 ?m, and having a compression breaking strength of at least 40 MPa; and a second composite oxide powder represented by the formula (2) LipNixCoyMnzNqOrFa (wherein N is aluminum or an alkaline earth metal element or a transition metal element other than Ni, Co and Mn, 0.9?p?1.1, 0.2?x?0.8, 0?y?0.4, 0?z?0.
    Type: Application
    Filed: December 14, 2006
    Publication date: May 3, 2007
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Takuya MIHARA, Yukimitsu Wakasugi, Naoshi Saito, Manabu Suhara
  • Patent number: 7192672
    Abstract: To provide a process for producing a lithium-cobalt composite oxide for a positive electrode of a lithium secondary battery, which has a large volume capacity density, high safety, high charge and discharge cycle durability, high press density and high productivity. A process for producing a lithium-cobalt composite oxide represented by the formula LipCoxMyOzFa (wherein M is a transition metal element other than Co, or an alkaline earth metal element, 0.9?p?1.1, 0.980?x?1.000, 0?y?0.02, 1.9?z?2.1, x+y=1, and 0?a?0.02), characterized in that as a cobalt source, a mixture is used which comprises cobalt hydroxide in the form of substantially spherical secondary particles with an average particle size of from 8 to 20 ?m formed by agglomeration of primary particles and tricobalt tetroxide in the form of secondary particles with an average particle size of from 2 to 10 ?m formed by agglomeration of primary particles, in a cobalt atomic ratio of from 5:1 to 1:5, and firing is carried out at from 700 to 1,050° C.
    Type: Grant
    Filed: May 25, 2005
    Date of Patent: March 20, 2007
    Assignee: Seimi Chemical Co., Ltd.
    Inventors: Kazushige Horichi, Manabu Suhara, Naoshi Saito, Megumi Uchida
  • Publication number: 20070026314
    Abstract: It is to provide a positive electrode active material for a lithium secondary battery, which has a large volume capacity density, high safety, excellent properties for uniform coating, excellent durability for charge and discharge cycles and low temperature characteristics even at a high charge voltage. A process for producing a lithium-containing composite oxide represented by the formula LipNxMmOzFa (wherein N is at least one element selected from the group consisting of Co, Mn and Ni, M is at least one element selected from the group consisting of Al, alkaline earth metal elements and transition metal elements other than N, 0.9?p?1.2, 0.9?x<1.00, 0<m?0.03, 1.9?z?2.2, x+m=1 and 0?a?0.02), which comprises using a solution comprising a complex containing the M element (M element-containing complex) dissolved in an organic solvent, an N source and a lithium source, and if necessary, a fluorine source, by means of a mixing step, an organic solvent removal step and a firing step.
    Type: Application
    Filed: September 29, 2006
    Publication date: February 1, 2007
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Takeshi Kawasato, Megumi Uchida, Toshiaki Abe, Naoshi Saito, Manabu Suhara
  • Publication number: 20060263690
    Abstract: A positive electrode active material for a lithium secondary battery containing a lithium-cobalt composite oxide, which has a large volume capacity density, has a high safety and is excellent in charge and discharge cyclic durability, and its production process, are provided. A lithium-cobalt composite oxide represented by the formula LipCoxMyOzFa (wherein M is a transition metal element other than Co or an alkaline earth metal element, 0.9?p?1.1, 0.980?x?1.000, 0?y?0.02, 1.9?z?2.1, x+y=1 and 0?a?0.
    Type: Application
    Filed: September 25, 2003
    Publication date: November 23, 2006
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Manabu Suhara, Naoshi Saito, Kazushige Horichi, Megumi Uchida
  • Publication number: 20060222951
    Abstract: A positive electrode material for a lithium secondary battery for high voltage high capacity use exhibiting high cycle durability and high safety. The positive electrode material is composed of particles having a composition represented by the general formula: LiaCObMgcAdOeFf (A is the group 6 transition element or the group 14 element, 0.90?a?1.10, 0.97?b?1.00, 0.0001?c>0.03, 0.0001?d?0.03, 1.98?e?2.02, 0?f?0.02 and 0.0001?c+d?0.03), and magnesium, the element A and fluorine exist uniformly in the vicinity of the surfaces of the particles.
    Type: Application
    Filed: August 16, 2004
    Publication date: October 5, 2006
    Inventors: Koji Tatsumi, Toshiaki Abe, Naoshi Saito, Manabu Suhara
  • Publication number: 20060210879
    Abstract: A lithium-containing composite oxide for a positive electrode for a lithium secondary battery is prepared by formulating a powder mixture by impregnating an N element source powder having an average particle size (D50) ranging from 2 to 20 ?m with an aqueous solution of a carboxylic acid having a total of two or more carboxylic acid groups or carboxylic acid groups and hydroxyl groups in its molecule, and optionally, containing an M element, or its salt, and then drying the material obtained; and firing the N element powder material in admixture with a lithium source, optionally, an M element source and a fluorine source, at a temperature ranging from 700° C. to 1050° C.
    Type: Application
    Filed: March 2, 2006
    Publication date: September 21, 2006
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Takeshi Kawasato, Megumi Uchida, Naoshi Saito, Manabu Suhara
  • Publication number: 20060154146
    Abstract: It is to provide a positive electrode active material for a lithium secondary battery, which has a large volume capacity density and high safety, is excellent in uniform coating properties and is excellent in the charge and discharge cyclic durability and low temperature characteristics even at a high charge voltage. A process for producing a lithium-containing composite oxide represented by the formula LipQqNxMyOzFa (wherein Q is at least one element selected from the group consisting of titanium, zirconium, niobium and tantalum, N is at least one element selected from the group consisting of Co, Mn and Ni, M is at least one element selected from the group consisting of Al, alkaline earth metal elements and transition metal elements other than the Q element and the N element, 0.9?p?1.1, 0<q?0.03, 0.97?x<1.00, 0?y<0.03, 1.9?z?2.1, q+x+y=1 and 0?a?0.
    Type: Application
    Filed: March 10, 2006
    Publication date: July 13, 2006
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Takeshi Kawasato, Naoshi Saito, Megumi Uchida, Kazushige Horichi, Koji Tatsumi, Kunihiko Terase, Manabu Suhara
  • Patent number: 7018741
    Abstract: A particulate positive electrode active material for a lithium secondary cell which satisfies high charge and discharge cyclic durability, high safety, high temperature storage properties, a high discharge average voltage, large current discharge properties, a high weight capacity density, a high volume capacity density, etc. in a well-balanced manner is provided. A particulate positive electrode active material for a lithium secondary cell, which is represented by the formula LipCoxMyOzFa (wherein M is at least one element selected from Groups 2 to 8, 13 and 14 of the Periodic Table, 0.9?p?1.1, 0.980?x?0.9999, 0.0001?y?0.02, 1.9?z?2.1, 0.9?x+y?1 and 0.0001?a?0.02), wherein fluorine atoms and element M are unevenly distributed on the particle surface, the atomic ratio of fluorine atoms to cobalt atoms (a/x) is from 0.0001 to 0.02, and in powder X-ray diffraction using CuK?-ray, the half value width of the angle of diffraction on (110) plane is from 0.06 to 0.
    Type: Grant
    Filed: August 12, 2004
    Date of Patent: March 28, 2006
    Assignee: Seimi Chemical Co., Ltd.
    Inventors: Manabu Suhara, Naoshi Saito, Tsutomu Kato, Megumi Yukawa
  • Publication number: 20050256289
    Abstract: The present invention provides a method for joining liquid-crystalline polyester resin composition parts, characterized in that the melting point of the liquid crystalline polyester resin measured by differential scanning calorimeter is 190-250° C. and that the parts are jointed by means of welding. By using the method of the present invention, jointed articles with sufficient joint strength are provided with accuracy.
    Type: Application
    Filed: May 10, 2005
    Publication date: November 17, 2005
    Inventors: Masaya Kitayama, Naoshi Saito
  • Publication number: 20050250013
    Abstract: There is obtained a material of a positive electrode for a secondary lithium-ion cell having high cycle durability and high safety in high-voltage and high-capacity applications, which is a particulate positive electrode active material for a secondary lithium-ion cell represented by a general formula, LiaCObAcBdOeFf (A is Al or Mg, B is a group-IV transition element, 0.90?a?1.10, 0.97?b?1.00, 0.0001?c?0.03, 0.0001?d?0.03, 1.98?e?2.02, 0?f?0.02, and 0.0001?c+d?0.03), where element A, element B and fluorine are evenly present in the vicinity of the particle surfaces.
    Type: Application
    Filed: June 6, 2003
    Publication date: November 10, 2005
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Koji Tatsumi, Manabu Suhara, Naoshi Saito, Kazushige Horichi, Yukio Jitsugiri
  • Publication number: 20050220701
    Abstract: To provide a process for producing a lithium-cobalt composite oxide for a positive electrode of a lithium secondary battery excellent in volume capacity density, safety, charge and discharge cyclic durability, press density and productivity, by using in expensive cobalt hydroxide and lithium carbonate. A mixture having a cobalt hydroxide powder and a lithium carbonate powder mixed so that the atomic ratio of lithium/cobalt would be from 0.98 to 1.01, is fired in an oxygen-containing atmosphere at from 250 to 700° C., and the fired product is further fired in an oxygen-containing atmosphere at from 850 to 1,050° C., or such a mixture is heated at a temperature-raising rate of at most 4° C./min in a range from 250 to 600° C. and fired in an oxygen-containing atmosphere at from 850 to 1,050° C.
    Type: Application
    Filed: May 13, 2005
    Publication date: October 6, 2005
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Manabu Suhara, Naoshi Saito, Kazushige Horichi, Koji Tatsumi
  • Publication number: 20050214645
    Abstract: To provide a process for producing a lithium-cobalt composite oxide for a positive electrode of a lithium secondary battery, which has a large volume capacity density, high safety, high charge and discharge cycle durability, high press density and high productivity. A process for producing a lithium-cobalt composite oxide represented by the formula LipCoxMyOzFa (wherein M is a transition metal element other than Co, or an alkaline earth metal element, O.9?p?1.1, 0.980?x?1.000, 0?y?0.02, 1.9?z?2.1, x+y=1, and 0?a?0.02), characterized in that as a cobalt source, a mixture is used which comprises cobalt hydroxide in the form of substantially spherical secondary particles with an average particle size of from 8 to 20 ?m formed by agglomeration of primary particles and tricobalt tetroxide in the form of secondary particles with an average particle size of from 2 to 10 ?m formed by agglomeration of primary particles, in a cobalt atomic ratio of from 5:1 to 1:5, and firing is carried out at from 700 to 1,050° C.
    Type: Application
    Filed: May 25, 2005
    Publication date: September 29, 2005
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Kazushige Horichi, Manabu Suhara, Naoshi Saito, Megumi Uchida
  • Patent number: 6929883
    Abstract: The present invention provides a lithium-transition metal composite oxide having a large volume capacity density, high safety, excellent coating uniformity, excellent charge/discharge cycle durability and excellent low temperature characteristics, and suitable as a positive electrode active material for a lithium secondary cell. A lithium-transition metal composite oxide which is represented by the formula LixM1?yNyO2 (wherein 0.2?x?1.2, 0?y?0.7, M is a transition metal element, and N is a transition metal element other than M or an alkaline earth metal element), wherein in the distribution curve of the cumulative volume particle size of said lithium composite oxide, the inclination of the curve at a cumulative volume fraction of 20% and 80% are at most 9%/?m and at least 3%/?m, respectively, and the average particle size is from 3 to 20 ?m.
    Type: Grant
    Filed: May 30, 2001
    Date of Patent: August 16, 2005
    Assignee: Seimi Chemical Co., Ltd.
    Inventors: Manabu Suhara, Megumi Yukawa, Naoshi Saito, Takashi Kimura, Kazuo Sunahara
  • Publication number: 20050019662
    Abstract: A particulate positive electrode active material for a lithium secondary cell which satisfies high charge and discharge cyclic durability, high safety, high temperature storage properties, a high discharge average voltage, large current discharge properties, a high weight capacity density, a high volume capacity density, etc. in a well-balanced manner is provided. A particulate positive electrode active material for a lithium secondary cell, which is represented by the formula LipCoxMyOzFa (wherein M is at least one element selected from Groups 2 to 8, 13 and 14 of the Periodic Table, 0.9?p?1.1, 0.980?x?0.9999, 0.0001?y?0.02, 1.9?z?2.1, 0.9?x+y?1 and 0.0001?a?0.02), wherein fluorine atoms and element M are unevenly distributed on the particle surface, the atomic ratio of fluorine atoms to cobalt atoms (a/x) is from 0.0001 to 0.02, and in powder X-ray diffraction using CuK?-ray, the half value width of the angle of diffraction on (110) plane is from 0.06 to 0.
    Type: Application
    Filed: August 12, 2004
    Publication date: January 27, 2005
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Manabu Suhara, Naoshi Saito, Tsutomu Kato, Megumi Yukawa
  • Publication number: 20040213729
    Abstract: The present invention provides a positive electrode, which has a large volume capacity density, high safety, and is excellent in the coating uniformity, the charge and discharge cyclic durability and the low-temperature properties.
    Type: Application
    Filed: May 21, 2004
    Publication date: October 28, 2004
    Applicant: Seimi Chemical Co., Ltd.
    Inventors: Manabu Suhara, Naoshi Saito, Kazushige Horichi, Megumi Uchida
  • Publication number: 20040023113
    Abstract: The present invention provides a lithium-transition metal composite oxide having a large volume capacity density, high safety, excellent coating uniformity, excellent charge/discharge cycle durability and excellent low temperature characteristics, and suitable as a positive electrode active material for a lithium secondary cell.
    Type: Application
    Filed: November 29, 2002
    Publication date: February 5, 2004
    Inventors: Manabu Suhara, Megumi Yukawa, Naoshi Saito, Takashi Kimura, Kazuo Sunahara
  • Patent number: 6664341
    Abstract: A liquid crystal polyester resin composition which suppresses the formation of a blister caused by a heat treatment at a high temperature and has excellent moldability. This composition comprises (A) a liquid crystal polyester comprising at least two aromatic oxycarbonyl recurring units and (B) a liquid crystal polyester comprising at least two aromatic oxycarbonyl recurring units, at least one aromatic dioxy recurring unit and at least one aromatic dicarbonyl recurring unit. The weight ratio of the liquid crystal polyester (A) to the liquid crystal polyester (B) is 90/10 to 30/70.
    Type: Grant
    Filed: December 14, 2001
    Date of Patent: December 16, 2003
    Assignee: Kabushiki Kaisha Ueno Seiyaku Oyo Kenkyusho
    Inventors: Masaya Kitayama, Kiichi Kometani, Naoshi Saito