Patents by Inventor Keiko Matsubara

Keiko Matsubara 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: 20020164479
    Abstract: Disclosed is a carbonaceous material comprising a graphite particle having a 002 plane interval d002 of less than 0.337 nm as measured by the X-ray wide angle diffraction method; a complex particle disposed and distributed in the vicinity of the surface of the graphite particle, the complex particle comprising silicon and carbon and having a particle size smaller than that of the graphite particle; and an amorphous carbon layer with a plane interval d002 of more than 0.37 nm, the amorphous carbon layer being a polymer layer and being coated on the graphite particle and the complex particle, wherein the complex particle comprises a Si particulate, a conductive carbon material disposed and distributed in the vicinity of the surface of the Si particulate, and a rigid carbon material layer coated on the Si particulate and the conductive carbon material, the Si particulate being composed of a crystalline Si phase.
    Type: Application
    Filed: March 1, 2002
    Publication date: November 7, 2002
    Inventors: Keiko Matsubara, Toshiaki Tsuno, Kyou-Yoon Sheem
  • Publication number: 20020039684
    Abstract: A negative electrode for a lithium rechargeable battery includes a carbon material in which lithium intercalation occurs, and at least one metallic oxide selected from yttrium oxide, cerium oxide, and titanium oxide.
    Type: Application
    Filed: August 8, 2001
    Publication date: April 4, 2002
    Inventors: Keiko Matsubara, Toshiaki Tsuno, Sang-Young Yoon
  • Publication number: 20020009646
    Abstract: Disclosed is a negative active material for a rechargeable lithium battery that includes graphite particles, silicon micro-particles attached on the graphite particles and a carbon film partially or totally coated on the graphite particles.
    Type: Application
    Filed: June 14, 2001
    Publication date: January 24, 2002
    Inventors: Keiko Matsubara, Toshiaki Tsuno, Sang-Young Yoon