Patents by Inventor Hee Tak Kim

Hee Tak Kim 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: 20060003214
    Abstract: A polymer electrolyte membrane for a fuel cell includes a porous membrane forming micropores. Proton-conducting polymers fill the micropores of the porous membrane. In addition, a method for preparing the polymer electrolyte membrane includes: preparing a porous membrane having a plurality of micropores; and filling the micropores with proton-conducting polymer.
    Type: Application
    Filed: June 30, 2005
    Publication date: January 5, 2006
    Inventors: Hee-Tak Kim, Hyoung-Juhn Kim, Ho-Jin Kweon
  • Publication number: 20060003212
    Abstract: A polymer electrolyte membrane for a fuel cell includes a proton conductive polymer membrane and proton conductive microfibers coated on either side of the proton conductive polymer membrane.
    Type: Application
    Filed: June 16, 2005
    Publication date: January 5, 2006
    Inventors: Hee-Tak Kim, Ho-Jin Kweon
  • Publication number: 20050287419
    Abstract: Disclosed is a membrane-electrode assembly for a fuel cell including an anode and a cathode with a polymer electrolyte membrane placed between them. At least one of the anode and the cathode includes a catalyst layer including a catalyst metal with a hydrophilic polymer layer on the catalyst metal.
    Type: Application
    Filed: May 11, 2005
    Publication date: December 29, 2005
    Inventors: Hee-Tak Kim, Myoung-Ki Min
  • Publication number: 20050287418
    Abstract: The electrode for a fuel cell of the invention includes: an electrode substrate; and a catalyst layer having a filler layer formed on the surface of the electrode substrate and a catalyst coating the filler layer.
    Type: Application
    Filed: May 11, 2005
    Publication date: December 29, 2005
    Inventors: Hyung-Gon Noh, Hee-Tak Kim, Jong-Ki Lee, Ho-Jin Kweon
  • Publication number: 20050271921
    Abstract: A membrane-electrode assembly for a fuel cell of the present invention includes a polymer electrolyte membrane with a layer of inorganic fine particles on either side. Catalyst layers are positioned on the layers of inorganic fine particles with gas diffusion layers positioned on the catalyst layers. The resulting polymer electrolyte membrane provides improved cell efficiency.
    Type: Application
    Filed: May 26, 2005
    Publication date: December 8, 2005
    Inventors: Hee-Tak Kim, Hyoung-Juhn Kim, Ho-Jin Kweon
  • Publication number: 20050095504
    Abstract: The present invention relates to a negative electrode for a lithium metal battery and a lithium metal battery comprising the same. The negative electrode of the present invention comprises a negative active material layer of metallic lithium or a lithium alloy, and a passivation layer formed on the negative active material layer. The passivation layer has a structure comprising a 3-dimensionally cross-linked polymer network matrix penetrated by linear polymers. The passivation layer formed on the surface of the negative electrode reduces reactivity of the negative electrode and stabilizes the surface, so that it offers a lithium metal battery having superior life cycle characteristics.
    Type: Application
    Filed: October 11, 2004
    Publication date: May 5, 2005
    Inventors: Hee-Tak Kim, Su-Suk Choi, Yun-Suk Choi, Sang-Eun Cheon, Ji-Seong Han
  • Patent number: 6731362
    Abstract: The present invention relates to a polymer blend of cinnamate polymer and polyimide polymer, which are photo-reactive polymers, for preparing liquid crystal alignment layer having a high pretilt angle in photo-alignment, a process for preparing liquid crystal alignment layer by employing the said blend, a liquid crystal alignment layer prepared by the process, and a crystal cell prepared by employing the liquid crystal alignment layer. The polymer blend for preparing liquid crystal alignment layer of the invention comprises 10 to 90% (w/w) of cinnamate polymer and 10 to 90% (w/w) of polyimide polymer. Since the liquid crystal alignment layer prepared by employing the polymer blend of the invention has an excellent alignment property and thermal stability, which makes possible its wide application in the development of liquid crystal displays.
    Type: Grant
    Filed: November 28, 2001
    Date of Patent: May 4, 2004
    Assignee: Korea Advanced Institute of Science and Technology
    Inventors: Jung-Ki Park, Hee-Tak Kim, Jong-Woo Lee, Shi-Joon Sung
  • Patent number: 6599333
    Abstract: Disclosed is a method of manufacturing a lithium secondary battery. A polymer mixture including a) polyvinylidene fluoride-based polymer and b) at least one polymer selected from the group consisting of polyacrylonitrile and polymethyl methacrylate is mixed with a solvent in which a lithium salt is dissolved. The mixing ratio of the polymer mixture and the solvent is about 1:3-10. Thus obtained first mixture is heated to obtain a polymer electrolyte composition. And this polymer electrolyte composition is coated onto a first electrode which is one of an anode and a cathode, and then dried to obtain a polymer electrolyte layer. Then, a second electrode which is a remaining one of the anode and cathode is attached onto the polymer electrolyte layer. The polymer electrolyte has a good mechanical strength and the lithium secondary battery has a stable charge/discharge characteristic.
    Type: Grant
    Filed: November 13, 2000
    Date of Patent: July 29, 2003
    Assignee: Ness Co., Ltd.
    Inventors: Hee Tak Kim, Jung Min Song, Sun Wook Kim
  • Patent number: 6521382
    Abstract: Disclosed are a method of preparing a polymer electrolyte composition and a method of manufacturing a lithium secondary battery employing the same. A polymer mixture including a) a polymer mixture including polyvinylidene fluoride-based polymer and b) at least one polymer selected from the group consisting of polyacrylonitrile and polymethyl methacrylate are mixed with a solvent in which a lithium salt is dissolved. The mixing ratio of the polymer mixture and the solvent is 1: 3-10. Thus obtained first mixture is stirred at a room temperature for 1-48 hours. Then, thus obtained second mixture is heated at 60-250° C. for 5 minutes-6 hours while stirring to prepare a polymer electrolyte composition. This composition is coated on at least one substrate selected from a group consisting of a molded film, an anode and a cathode and then dried. The polymer electrolyte has a good mechanical strength and the lithium secondary battery has a stable charge/discharge characteristic and a high capacity.
    Type: Grant
    Filed: November 13, 2000
    Date of Patent: February 18, 2003
    Assignee: Ness Energy Co., Ltd.
    Inventors: Jung Min Song, Hee Tak Kim, Sun Wook Kim
  • Publication number: 20020188075
    Abstract: The present invention relates to a polymer blend of cinnamate polymer and polyimide polymer, which are photo-reactive polymers, for preparing liquid crystal alignment layer having a high pretilt angle in photo-alignment, a process for preparing liquid crystal alignment layer by employing the said blend, a liquid crystal alignment layer prepared by the process, and a crystal cell prepared by employing the liquid crystal alignment layer. The polymer blend for preparing liquid crystal alignment layer of the invention comprises 10 to 90% (w/w) of cinnamate polymer and 10 to 90% (w/w) of polyimide polymer. Since the liquid crystal alignment layer prepared by employing the polymer blend of the invention has an excellent alignment property and thermal stability, which makes possible its wide application in the development of liquid crystal displays.
    Type: Application
    Filed: November 28, 2001
    Publication date: December 12, 2002
    Inventors: Jung-Ki Park, Hee-Tak Kim, Jong-Woo Lee, Shi-Joon Sung
  • Patent number: 6403266
    Abstract: Disclosed are a polymer electrolyte composition, a method for preparing the same and a lithium secondary battery employing the same. The polymer electrolyte composition comprises a polymer mixture and a solvent in which a lithium salt is disclosed. The polymer mixture includes polyvinylidene fluoride-based polymer and at least one polymer selected from the group consisting of polyacrylonitrile and polymethyl methacrylate. Polyvinylidene fluoride-based polymer which has a good mechanical strength, polymethyl methacrylate polymer which has a good affinity and polyacrylonitrile polymer which has a good adhesiveness to electrodes are utilized. As a result, the mechanical strength and the adhesiveness to the electrodes of the polymer electrolyte can be improved to obtain a lithium secondary battery which has a stable charge/discharge characteristic and a high capacity.
    Type: Grant
    Filed: January 18, 2000
    Date of Patent: June 11, 2002
    Assignee: Ness Energy Co., Ltd.
    Inventors: Hee Tak Kim, Kyoung Bae Kim, Sun Wook Kim