Patents by Inventor Kazuyuki Takeishi

Kazuyuki Takeishi 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).

  • Active material of positive electrode for non-aqueous electrolyte secondary battery and method for preparing the same and non-aqueous electrolyte secondary battery using the same
    Patent number: 6794036
    Abstract: In an active material of a positive electrode for a non-aqueous electrolyte secondary battery where lithium cobaltate represented by the formula LiCoO2 is used, which comprises a mixture of primary particles of small crystals falling in the range of 0.4 to 10 &mgr;m in Feret's diameter in a projection chart by SEM observation and having an average diameter of 5 &mgr;m or less and secondary particles formed by gathering of a number of said small crystals and having an average particle size falling in the range of 4 to 30 &mgr;m where the molar ratio of Co to Li is 0.97 or more to 1.03 or less, at least part of the small crystals constituting the secondary particles are jointed by sintering and furthermore, the secondary particles are preferably spherical or elliptical.
    Type: Grant
    Filed: August 15, 2003
    Date of Patent: September 21, 2004
    Assignee: Sumitomo Metal Mining Co., Ltd.
    Inventors: Kazutoshi Matsumoto, Tomio Tujimura, Kazuyuki Takeishi
  • Active material of positive electrode for non-aqueous electrolyte secondary battery and method for preparing the same and non-aqueous electrolyte secondary battery using the same
    Publication number: 20040053135
    Abstract: In an active material of a positive electrode for a non-aqueous electrolyte secondary battery where lithium cobaltate represented by the formula LiCoO2 is used, which comprises a mixture of primary particles of small crystals falling in the range of 0.4 to 10 &mgr;m in Feret's diameter in a projection chart by SEM observation and having an average diameter of 5 &mgr;m or less and secondary particles formed by gathering of a number of said small crystals and having an average particle size falling in the range of 4 to 30 &mgr;m where the molar ratio of Co to Li is 0.97 or more to 1.03 or less, at least part of the small crystals constituting the secondary particles are jointed by sintering and furthermore, the secondary particles are preferably spherical or elliptical.
    Type: Application
    Filed: August 15, 2003
    Publication date: March 18, 2004
    Inventors: Kazutoshi Matsumoto, Tomio Tujimura, Kazuyuki Takeishi
  • Active material of positive electrode for non-aqueous electrode secondary battery and method for preparing the same and non-aqueous electrode secondary battery using the same
    Patent number: 6617073
    Abstract: In an active material of a positive electrode for a non-aqueous electrolyte secondary battery where lithium cobaltate represented by the formula LiCoO2 is used, which comprises a mixture of primary particles of small crystals falling in the range of 0.4 to 10 &mgr;m in Feret's diameter in a projection chart by SEM observation and having an average diameter of 5 &mgr;m or less and secondary particles formed by gathering of a number of said small crystals and having an average particle size falling in the range of 4 to 30 &mgr;m where the molar ratio of Co to Li is 0.97 or more to 1.03 or less, at least part of the small crystals constituting the secondary particles are jointed by sintering and furthermore, the secondary particles are preferably spherical or elliptical.
    Type: Grant
    Filed: September 25, 2000
    Date of Patent: September 9, 2003
    Assignee: Sumitomo Metal Mining Co., Ltd.
    Inventors: Kazutoshi Matsumoto, Tomio Tujimura, Kazuyuki Takeishi