Patents by Inventor Yasuhiro Kawahashi

Yasuhiro Kawahashi 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: 9327996
    Abstract: The present invention provides a method for producing a positive electrode active material for lithium ion battery, having excellent tap density, at excellent production efficiency, and a positive electrode active material for lithium ion battery. The method for producing a positive electrode active material for lithium ion battery including a step of conducting a main firing after increasing mass percent of all metals in lithium-containing carbonate by 1% to 105% compared to the mass percent of all metals before a preliminary firing, by conducting the step of a preliminary firing to the lithium-containing carbonate, which is a precursor for positive electrode active material for lithium ion battery, with a rotary kiln.
    Type: Grant
    Filed: August 24, 2011
    Date of Patent: May 3, 2016
    Assignee: JX Nippon Mining & Metals Corporation
    Inventors: Yasuhiro Kawahashi, Yoshio Kajiya
  • Patent number: 9263732
    Abstract: The present invention provides a positive electrode active material for lithium ion batteries, which realizes a lithium ion battery that is, while satisfying fundamental characteristics of a battery (capacity, efficiency, load characteristics), low in the resistance and excellent in the lifetime characteristics. In the positive electrode active material for lithium ion batteries, the variation in the composition of transition metal that is a main component inside of particles of or between particles of the positive electrode active material, which is defined as a ratio of the absolute value of the difference between a composition ratio inside of the particles of or in a small area between the particles of the transition metal and a composition ratio in a bulk state to the composition ratio in a bulk state of the transition metal, is 5% or less.
    Type: Grant
    Filed: December 23, 2014
    Date of Patent: February 16, 2016
    Assignee: JX Nippon Mining & Metals Corporation
    Inventors: Ryuichi Nagase, Yasuhiro Kawahashi
  • Patent number: 9221693
    Abstract: The present invention provides a method for producing a high quality positive electrode active material for lithium ion batteries at low cost and at excellent production efficiency. The method for producing a positive electrode active material for lithium ion batteries includes a step of firing a powder of lithium-containing carbonate that is a precursor for positive electrode active material for lithium ion batteries in a rotary kiln. In the step, a temperature at a powder feed part inside of the rotary kiln is kept at 500° C. or more.
    Type: Grant
    Filed: October 4, 2011
    Date of Patent: December 29, 2015
    Assignee: JX Nippon Mining & Metals Corporation
    Inventors: Yasuhiro Kawahashi, Yoshio Kajiya
  • Publication number: 20150123029
    Abstract: The present invention provides a positive electrode active material for lithium ion batteries, which realizes a lithium ion battery that is, while satisfying fundamental characteristics of a battery (capacity, efficiency, load characteristics), low in the resistance and excellent in the lifetime characteristics. In the positive electrode active material for lithium ion batteries, the variation in the composition of transition metal that is a main component inside of particles of or between particles of the positive electrode active material, which is defined as a ratio of the absolute value of the difference between a composition ratio inside of the particles of or in a small area between the particles of the transition metal and a composition ratio in a bulk state to the composition ratio in a bulk state of the transition metal, is 5% or less.
    Type: Application
    Filed: December 23, 2014
    Publication date: May 7, 2015
    Inventors: Ryuichi Nagase, Yasuhiro Kawahashi
  • Patent number: 8623551
    Abstract: The present invention provides a positive electrode active material for a lithium ion battery having good battery performance can be provided. The positive electrode active material for a lithium ion battery is represented by; Compositional formula:LixNi1?yMyO2+? wherein M is one or more selected from Sc, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Ga, Ge, Al, Bi, Sn, Mg, Ca, B, and Zr, 0.9?x?1.1, 0<y?0.7, and 0.05???0.2, and contains primary particles and has a tap density of 1.3 to 2.6 g/cm3. The average particle size of the primary particles is 0.3 to 3.0 ?m and the specific surface area is 0.3 to 2.3 m2/g.
    Type: Grant
    Filed: March 4, 2011
    Date of Patent: January 7, 2014
    Assignee: JX Nippon Mining & Metals Corporation
    Inventors: Yasuhiro Kawahashi, Kentaro Okamoto
  • Publication number: 20130175470
    Abstract: An object of the present invention is to reduce the time required for the calcination of a lithium metal salt complex to thereby provide a high-quality cathode active material for a lithium ion battery at low cost. The method for producing a cathode active material for a lithium ion battery comprises the steps of: preparing a lithium metal salt solution slurry containing a lithium salt and a metal salt containing an oxidizer or a metal salt containing ions having an oxygenation effect; drying the lithium metal salt solution slurry to obtain a powder of a lithium metal salt complex containing an oxidizer or a powder of a lithium metal salt complex containing a metal salt containing ions having an oxygenation effect; and calcining the powder.
    Type: Application
    Filed: December 20, 2011
    Publication date: July 11, 2013
    Applicant: JX NIPPON MINING & METALS CORPORATION
    Inventors: Yoshio Kajiya, Yasuhiro Kawahashi, Ryuichi Nagase
  • Publication number: 20130043428
    Abstract: The present invention provides a method for producing a high quality positive electrode active material for lithium ion batteries at low cost and at excellent production efficiency. The method for producing a positive electrode active material for lithium ion batteries includes a step of firing a powder of lithium-containing carbonate that is a precursor for positive electrode active material for lithium ion batteries in a rotary kiln. In the step, a temperature at a powder feed part inside of the rotary kiln is kept at 500° C. or more.
    Type: Application
    Filed: October 4, 2011
    Publication date: February 21, 2013
    Applicant: JX NIPPON MINING & METALS CORPORATION
    Inventors: Yasuhiro Kawahashi, Yoshio Kajiya
  • Publication number: 20120319037
    Abstract: The present invention provides a method for producing a positive electrode active material for lithium ion battery, having excellent tap density, at excellent production efficiency, and a positive electrode active material for lithium ion battery. The method for producing a positive electrode active material for lithium ion battery including a step of conducting a main firing after increasing mass percent of all metals in lithium-containing carbonate by 1% to 105% compared to the mass percent of all metals before a preliminary firing, by conducting the step of a preliminary firing to the lithium-containing carbonate, which is a precursor for positive electrode active material for lithium ion battery, with a rotary kiln.
    Type: Application
    Filed: August 24, 2011
    Publication date: December 20, 2012
    Applicant: JX NIPPON MINING & METALS CORPORATION
    Inventors: Yasuhiro Kawahashi, Yoshio Kajiya
  • Publication number: 20120321956
    Abstract: The present invention provides a positive electrode active material for a lithium ion battery having good battery performance can be provided. The positive electrode active material for a lithium ion battery is represented by; Compositional formula:LixNi1-yMyO2? wherein M is one or more selected from Sc, Ti, V, Cr, Mn, Fe, Co, Cu, Zn, Ga, Ge, Al, Bi, Sn, Mg, Ca, B, and Zr, 0.9?x?1.1, 0<y?0.7, and 0.05???0.2, and contains primary particles and has a tap density of 1.3 to 2.6 g/cm3. The average particle size of the primary particles is 0.3 to 3.0 ?m and the specific surface area is 0.3 to 2.3 m2/g.
    Type: Application
    Filed: March 4, 2011
    Publication date: December 20, 2012
    Applicant: JX NIPPON MINING & METALS CORPORATION
    Inventors: Yasuhiro Kawahashi, Kentaro Okamoto
  • Publication number: 20120231343
    Abstract: The present invention provides a positive electrode active material for lithium ion batteries, which realizes a lithium ion battery that is, while satisfying fundamental characteristics of a battery (capacity, efficiency, load characteristics), low in the resistance and excellent in the lifetime characteristics. In the positive electrode active material for lithium ion batteries, the variation in the composition of transition metal that is a main component inside of particles of or between particles of the positive electrode active material, which is defined as a ratio of the absolute value of the difference between a composition ratio inside of the particles of or in a small area between the particles of the transition metal and a composition ratio in a bulk state to the composition ratio in a bulk state of the transition metal, is 5% or less.
    Type: Application
    Filed: December 3, 2010
    Publication date: September 13, 2012
    Applicant: JX NIPPON MINING & METALS CORPORATION
    Inventors: Ryuichi Nagase, Yasuhiro Kawahashi