Patents by Inventor Kyung-Yoon Chung

Kyung-Yoon Chung 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: 20140349177
    Abstract: The present disclosure relates to a magnesium hybrid battery and a method for fabricating same. The magnesium hybrid battery according to the present disclosure, which includes magnesium or magnesium alloy metal as an anode, a cathode including a cathode active material wherein not only magnesium ion but also one or more ion selected from lithium ion and sodium ion can be intercalated and deintercalated and an electrolyte including magnesium ion and further including one or more ion selected from lithium ion and sodium, can overcome the limitation of the existing magnesium secondary battery and provide improved battery capacity, output characteristics, cycle life, safety, etc.
    Type: Application
    Filed: September 3, 2013
    Publication date: November 27, 2014
    Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Kyung Yoon CHUNG, Byung Won CHO, Joong Kee LEE, Hyung Sun KIM, Jae Hyun CHO, Won Young CHANG, Hwa Young LEE
  • Patent number: 8889297
    Abstract: The present disclosure relates to a nanocomposite cathode active material for a lithium secondary battery, a method for preparing same, and a lithium secondary battery including same. More particularly, the present disclosure relates to a nanocomposite cathode active material for a lithium secondary battery including: a core including LiMn2O4; and LiMn(PO3)3 distributed on the surface of the core. In accordance with the present disclosure, the time and cost for manufacturing a lithium secondary battery can be reduced and the manufactured lithium secondary battery has superior electrochemical properties.
    Type: Grant
    Filed: January 10, 2013
    Date of Patent: November 18, 2014
    Assignee: Korea Institute of Science and Technology
    Inventors: Kyung Yoon Chung, Dieky Susanto, Won Young Chang, Byung Won Cho
  • Publication number: 20140264185
    Abstract: The present invention relates to a method for recycling LiFePO4, which is an olivine-based cathode material for a lithium secondary battery. The present invention is characterized in that a cathode material including LiFePO4 is synthesized using, as precursors, amorphous FePO4.XH2O and crystalline FePO4.2H2O (metastrengite) obtained by chemically treating LiFePO4 as an olivine-based cathode material for a lithium secondary battery, which is produced from a waste battery. Since a cathode fabricated from the LiFePO4 cathode material synthesized according to the present invention does not deteriorate the capacity, output characteristics, cycle efficiency and performance of the secondary battery and the cathode material of the lithium secondary battery may be recycled, the secondary battery is economically efficient.
    Type: Application
    Filed: July 17, 2013
    Publication date: September 18, 2014
    Inventors: Hyung Sun KIM, Byung Won CHO, Hwa Young LEE, Eun Jung SHIN, Soo KIM, Kyung Yoon CHUNG
  • Patent number: 8835026
    Abstract: Disclosed are a recovery for a metaloxidic cathodic active material for a lithium ion secondary battery and a synthesis thereof by the recovery method, wherein the recovery method includes (a) dissolving a cathodic active material from a waste lithium ion secondary battery using sulfuric acid solution containing sulfurous acid gas to generate a solution containing metal ions, (b) injecting sodium hydroxide solution and ammonia solution in the solution containing the metal ions to fabricate an electrode active material precursor, and (c) filtrating the active material precursor, followed by drying and grinding, thus to fabricate a solid-state cathodic active material precursor, and the synthesis method is achieved by mixing the electrode active material precursor fabricated according to the recovery method with lithium carbonate or lithium hydroxide, followed by heat treatment, to generate a metaloxidic cathodic active material.
    Type: Grant
    Filed: January 27, 2011
    Date of Patent: September 16, 2014
    Assignee: Korea Institute of Science and Technology
    Inventors: Kyung Yoon Chung, Hwa Young Lee, Byung-Won Cho
  • Patent number: 8741254
    Abstract: The present invention relates to a method of preparing a porous silicon nanorod structure composed of columnar bundles having a diameter of 50-100 nm and a length of 2-5 ?m, and a lithium secondary cell using the porous silicon nanorod structure as an anode active material. The present invention provides a high-capacity and high-efficiency anode active material for lithium secondary cells, which can overcome the low conductivity of silicon and improve the electrode deterioration attributable to volume expansion because it is prepared by electrodepositing the surface of silicon powder with metal and simultaneously etching the silicon powder partially using hydrofluoric acid.
    Type: Grant
    Filed: August 4, 2009
    Date of Patent: June 3, 2014
    Assignee: Korea Institute of Science and Technology
    Inventors: Joong Kee Lee, Byung Won Cho, Joo Man Woo, Hyung Sun Kim, Kyung Yoon Chung, Won Young Chang, Sang Ok Kim, Sang Eun Park
  • Publication number: 20140141324
    Abstract: Provided are an electrolyte for a magnesium secondary battery having improved ion conductivity and stability, and a method for preparing the same. The electrolyte for a magnesium secondary battery shows higher ion conductivity as compared to the electrolyte according to the related art, increases the dissociation degree of a magnesium halide electrolyte salt, and provides stable electrochemical characteristics. In addition, after determining the capacity, output characteristics and cycle life of the magnesium secondary battery including the electrolyte, the battery provides significantly higher discharge capacity after 100 cycles, as compared to the electrolyte according to the related art. Therefore, the electrolyte may be useful for an electrolyte solution of a magnesium secondary battery.
    Type: Application
    Filed: April 25, 2013
    Publication date: May 22, 2014
    Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Kyung Yoon CHUNG, Byung Won CHO, Joong Kee LEE, Jae Hyun CHO, Sang Hoon LEE, Won Young CHANG
  • Patent number: 8729382
    Abstract: A photovoltaic-charged secondary battery system is provided, in which an electrode for optical power generation and an electrode for charging and discharging generated electrical energy are integrated into a single cell structure, and the potential difference between the electrodes is systematically controlled, thus maximizing the conversion efficiency of optical energy, maximizing the utilization rate of cell energy, and extending the life span of the battery. Thus, the photovoltaic-charged secondary battery system may include a transparent electrode capable of transmitting light; a PN semiconductor layer formed on the transparent electrode and generating a current by incident light; and a secondary battery layer, formed on the PN semiconductor layer, in which the current generated by the PN semiconductor layer is charged.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: May 20, 2014
    Assignee: Korea Institute of Science and Technology
    Inventors: Joong Kee Lee, Byung Won Cho, Kyung Yoon Chung, Hyung Sun Kim, Il Doo Kim, Chan Wook Jeon, Yong Sang Kim
  • Publication number: 20130313485
    Abstract: The present invention relates to a method for fabricating a LiFePO4 cathode electroactive material for a lithium secondary battery by recycling, and a LiFePO4 cathode electroactive material for a lithium secondary battery, a LiFePO4 cathode, and a lithium secondary battery fabricated thereby. The present invention is characterized in that a cathode scrap is heat treated in air for a cathode electroactive material to be easily dissolved in an acidic solution, and amorphous FePO4 obtained as precipitate is heat treated in an atmosphere of air or hydrogen so as to fabricate crystalline FePO4 or Fe2P2O7. According to the present invention, a cathode scrap may be recycled by using a simple, environmentally friendly, and economical method. Further, a lithium secondary battery fabricated by using a LiFePO4 cathode electroactive material from the cathode scrap is not limited in terms of performance.
    Type: Application
    Filed: October 15, 2012
    Publication date: November 28, 2013
    Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Hyung Sun KIM, Byung Won CHO, Hwa Young LEE, Su Jin KIM, Eun Jung SHIN, Kyung Yoon CHUNG
  • Patent number: 8585874
    Abstract: Disclosed is a method of preparing a positive active material for a lithium battery. The method comprises: depositing a positive active material on an electrode on a substrate (1); and putting metal chips on a metal oxides target and performing a sputtering process, thereby depositing mixed metal-oxides on the positive active material (2). In another aspect, the method comprises: preparing an electrode active material; preparing a precursor solution including the electrode active material; and printing the precursor solution on the substrate, and evaporating a solvent at a temperature of 80-120° C.
    Type: Grant
    Filed: November 25, 2009
    Date of Patent: November 19, 2013
    Assignee: Korea Institue of Science and Technology
    Inventors: Kyung Yoon Chung, Byung Won Cho, Seong-rae Lee, Hwa Young Lee, Ji-Ae Choi
  • Publication number: 20130299735
    Abstract: Disclosed is a method of producing a nanocomposite cathode active material for a lithium secondary battery, represented by the following formula: xLi2MnO3—(1?x)LiMO2 wherein M is Nia—Mnb—Coc, x is a decimal number from 0.1 to 0.9, and a, b and c are independently a decimal number from 0.05 to 0.9. The method includes mixing a lithium compound with a manganese compound to prepare Li2MnO3 as a first cathode active material, mixing a mixed solution of nickel sulfate/manganese sulfate/cobalt sulfate, a sodium hydroxide solution and aqueous ammonia to prepare a coprecipitated hydroxide represented by (Nia—Mnb—Coc)(OH)2 wherein a, b and c are as defined above, mixing the coprecipitated hydroxide with a lithium compound to prepare a second cathode active material represented by LiMO2 wherein M is as defined above, and mixing the first cathode active material with the second cathode active material.
    Type: Application
    Filed: March 29, 2013
    Publication date: November 14, 2013
    Applicant: Korea Institute of Science and Technology
    Inventors: Kyung Yoon CHUNG, Byung Won CHO, Won Young CHANG, Jae Hyung CHO, Jae-kyo NOH, Soo KIM, Sujin KIM
  • Publication number: 20120326078
    Abstract: Disclosed is a method for preparing a cathode active material represented by Li2MSiO4 (M=transition metal) for a lithium secondary battery using microwaves, including: 1) dispersing a silicon compound in a solvent; 2) mixing a lithium salt and a transition metal salt in the resulting dispersion and then adding a chelating agent to form complex ions: and 3) treating the mixture with microwaves for gelation. The prepared cathode active material represented by Li2MSiO4 (M=transition metal) for a lithium secondary battery has homogeneous composition and superior characteristics. Further, since the preparation process is simple, the production efficiency is good.
    Type: Application
    Filed: November 1, 2011
    Publication date: December 27, 2012
    Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Kyung Yoon CHUNG, Won Bin IM, Byung Won CHO, Won Young CHANG, Hyung Sun KIM
  • Publication number: 20120202120
    Abstract: A method for synthesizing lithium titanium oxide-based anode active material nanoparticles, and more particularly, a method for synthesizing lithium titanium oxide-based anode active material nanoparticles using a supercritical fluid condition is disclosed herein. The method may include (a) preparing a lithium precursor solution and a titanium precursor solution, (b) forming lithium titanium oxide-based anode active material nanoparticles by introducing the lithium precursor solution and titanium precursor solution into an reactor at a supercritical fluid condition, and (c) cleaning and drying the nanoparticles, and may further include (d) calcinating the nanoparticles at 500-1000° C. for 10 minutes to 24 hours after the step (c).
    Type: Application
    Filed: October 3, 2011
    Publication date: August 9, 2012
    Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Jaehoon KIM, Kyung Yoon CHUNG, Byung Won CHO, Nugroho AGUNG, Jong Min PARK
  • Patent number: 8211572
    Abstract: Disclosed is a fabrication method for an electrode active material, and a lithium battery comprising an electrode active material fabricated therefrom. The fabrication method for an electrode active material comprises preparing an aqueous solution by dissolving a precursor that can simultaneously undergo positive ion substitution and surface-reforming processes in water; mixing and dissolving raw materials for an electrode active material with a composition ratio for a final electrode active material in the aqueous solution, thereby preparing a mixed solution; removing a solvent from the mixed solution, thereby forming a solid dry substance; thermal- processing the solid dry substance; and crushing the thermal-processed solid dry substance.
    Type: Grant
    Filed: October 30, 2008
    Date of Patent: July 3, 2012
    Assignee: Korea Institute of Science and Technology
    Inventors: Byung-Won Cho, Kyung-Yoon Chung, Joong-Kee Lee
  • Patent number: 8168328
    Abstract: Disclosed are a silicon thin film anode for a lithium secondary battery having enhanced cycle characteristics and capacity and a preparation method thereof. A preparation method for a silicon thin film anode for a lithium secondary battery, comprises: preparing a collector including a metal; forming an anode active material layer including a silicon on the collector; forming one or more interface stabilizing layer, by annealing the collector and the anode active material layer under one of an inert atmosphere, a reduced atmosphere, and a vacuum atmosphere to react a metallic component of at least one of the collector and the anode active material layer with a silicon component of the anode active material layer at an interface therebetween; and forming a carbon coating layer on the anode active material layer by performing an annealing process in a hydrocarbon atmosphere.
    Type: Grant
    Filed: August 27, 2008
    Date of Patent: May 1, 2012
    Assignee: Korea Institute of Science and Technology
    Inventors: Hyung-Sun Kim, Byung-Won Cho, Kyung-Yoon Chung, Joong-Kee Lee, Taeg-Kwan Kang, Young-Hwan Jung
  • Publication number: 20120068107
    Abstract: Disclosed are a recovery for a metaloxidic cathodic active material for a lithium ion secondary battery and a synthesis thereof by the recovery method, wherein the recovery method includes (a) dissolving a cathodic active material from a waste lithium ion secondary battery using sulfuric acid solution containing sulfurous acid gas to generate a solution containing metal ions, (b) injecting sodium hydroxide solution and ammonia solution in the solution containing the metal ions to fabricate an electrode active material precursor, and (c) filtrating the active material precursor, followed by drying and grinding, thus to fabricate a solid-state cathodic active material precursor, and the synthesis method is achieved by mixing the electrode active material precursor fabricated according to the recovery method with lithium carbonate or lithium hydroxide, followed by heat treatment, to generate a metaloxidic cathodic active material.
    Type: Application
    Filed: January 27, 2011
    Publication date: March 22, 2012
    Applicant: Korea Institute of Science and Technology
    Inventors: Kyung Yoon CHUNG, Hwa Young Lee, Byung-Won Cho
  • Publication number: 20110056824
    Abstract: Disclosed is a method of preparing a positive active material for a lithium battery. The method comprises: depositing a positive active material on an electrode on a substrate (1); and putting metal chips on a metal oxides target and performing a sputtering process, thereby depositing mixed metal-oxides on the positive active material (2). In another aspect, the method comprises: preparing an electrode active material; preparing a precursor solution including the electrode active material; and printing the precursor solution on the substrate, and evaporating a solvent at a temperature of 80-120° C.
    Type: Application
    Filed: November 25, 2009
    Publication date: March 10, 2011
    Inventors: Kyung Yoon CHUNG, Byung Won CHO, Seong-rae LEE, Hwa Young LEE, Ji-Ae CHOI
  • Publication number: 20100301276
    Abstract: The present invention relates to a method of preparing a porous silicon nanorod structure composed of columnar bundles having a diameter of 50-100 nm and a length of 2-5 ?m, and a lithium secondary cell using the porous silicon nanorod structure as an anode active material. The present invention provides a high-capacity and high-efficiency anode active material for lithium secondary cells, which can overcome the low conductivity of silicon and improve the electrode deterioration attributable to volume expansion because it is prepared by electrodepositing the surface of silicon powder with metal and simultaneously etching the silicon powder partially using hydrofluoric acid.
    Type: Application
    Filed: August 4, 2009
    Publication date: December 2, 2010
    Inventors: Joong Kee LEE, Byung Won Cho, Joo Man Woo, Hyung Sun Kim, Kyung Yoon Chung, Won Young Chang, Sang Ok Kim, Sang Eun Park
  • Publication number: 20100092868
    Abstract: Disclosed are a carbon nanotube-coated silicon/metal composite particle, a preparation method thereof, an anode for a secondary battery comprising the carbon nanotube-coated silicon/metal composite particle, and a secondary battery comprising the anode, wherein the carbon nanotube-coated silicon/metal composite particle characterized in comprising: a composite particle of silicon and metal; and a carbon nanotube coated on the surface of the composite particle of silicon and metal, wherein the carbon nanotube-coated silicon/metal composite particle may be prepared by preparing composite particle of silicon and metal, followed by treating the composite particles of silicon and metal with heat under a mixed gas atmosphere of an inert gas and a hydrocarbon gas.
    Type: Application
    Filed: October 13, 2009
    Publication date: April 15, 2010
    Inventors: Hyung-Sun KIM, Byung Won CHO, Kyung Yoon CHUNG, Joong Kee LEE, Won Il CHO
  • Publication number: 20090117464
    Abstract: Disclosed is a fabrication method for an electrode active material, and a lithium battery comprising an electrode active material fabricated therefrom. The fabrication method for an electrode active material comprises preparing an aqueous solution by dissolving a precursor that can simultaneously undergo positive ion substitution and surface-reforming processes in water; mixing and dissolving raw materials for an electrode active material with a composition ratio for a final electrode active material in the aqueous solution, thereby preparing a mixed solution; removing a solvent from the mixed solution, thereby forming a solid dry substance; thermal-processing the solid dry substance; and crushing the thermal-processed solid dry substance.
    Type: Application
    Filed: October 30, 2008
    Publication date: May 7, 2009
    Applicant: KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY
    Inventors: Byung-Won Cho, Kyung-Yoon Chung, Joong-Kee Lee
  • Publication number: 20090072780
    Abstract: The present invention provides a photovoltaic-charged secondary battery system, in which an electrode for optical power generation and an electrode for charging and discharging generated electrical energy are integrated into a single cell structure, and the potential difference between the electrodes is systematically controlled, thus maximizing the conversion efficiency of optical energy, maximizing the utilization rate of cell energy, and extending the life span of the battery. For this, the present invention provides a photovoltaic-charged secondary battery system including: a transparent electrode capable of transmitting light; a PN semiconductor layer formed on the transparent electrode and generating a current by incident light; and a secondary battery layer, formed on the PN semiconductor layer, in which the current generated by the PN semiconductor layer is charged.
    Type: Application
    Filed: December 21, 2007
    Publication date: March 19, 2009
    Inventors: Joong Kee Lee, Byung Won Cho, Kyung Yoon Chung, Hyung Sun Kim, Il Doo Kim, Chan Wook Jeon, Yong Sang Kim