Patents by Inventor Kyung-yeon Kang

Kyung-yeon Kang 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: 11964870
    Abstract: The present invention relates to a method for preparing carbon nanotubes, the method including: preparing a support including AlO(OH) by primary heat treatment of Al(OH)3; preparing an active carrier by supporting a mixture including a main catalyst precursor and a cocatalyst precursor on the support; drying the active carrier through multi-stage drying including vacuum drying; preparing a supported catalyst by secondary heat treatment of the dried active support; and preparing carbon nanotubes in the presence of the supported catalyst, and the carbon nanotubes prepared by the method as described above can remarkably improve conductivity.
    Type: Grant
    Filed: July 22, 2019
    Date of Patent: April 23, 2024
    Assignee: LG CHEM, LTD.
    Inventors: Kyung Yeon Kang, Hyun Joon Kang, Ki Soo Lee
  • Patent number: 11511994
    Abstract: The present invention relates to carbon nanotubes having a pore volume of 0.94 cm3/g or more, and being an entangled type, a method of manufacturing the same, and a positive electrode for a primary battery which comprises the same.
    Type: Grant
    Filed: July 26, 2019
    Date of Patent: November 29, 2022
    Assignee: LG CHEM, LTD.
    Inventors: Kyung Yeon Kang, Hyun Joon Kang, Ki Soo Lee, Soon Ki Jeong
  • Patent number: 11453592
    Abstract: The present invention relates to a method for preparing a carbon nanotube dispersion, the method including mixing a dispersion solution including a dispersion solvent and a dispersant with carbon nanotubes to prepare carbon nanotube paste, extruding the paste to obtain solid carbon nanotubes, and introducing a second solvent to the solid carbon nanotubes, and homogenizing the carbon nanotubes, wherein the weight ratio of the dispersion solution and the carbon nanotubes is 1:1 to 9:1. According to the present invention, the mixing of a dispersant and carbon nanotubes is increased and the particle size is controlled by a wet method, so that a carbon nanotube dispersion having a viscosity controlled to a low level, excellent resistance properties, and a high concentration, may be provided.
    Type: Grant
    Filed: January 21, 2019
    Date of Patent: September 27, 2022
    Assignee: LG CHEM, LTD.
    Inventors: Kyung Yeon Kang, Seung Yong Lee, Seok Won Kim, Hyun Joon Kang
  • Patent number: 11267710
    Abstract: In the present invention, by dry pulverizing carbon nanotubes to control wettability index of the carbon nanotubes, the maximum concentration of the carbon nanotubes that can be added to the dispersion solvent can be increased and the workability of the carbon nanotube dispersion can be improved. Further, from this, it is possible to more easily predict the maximum concentration of the carbon nanotubes that can be added to the dispersion solvent.
    Type: Grant
    Filed: January 5, 2018
    Date of Patent: March 8, 2022
    Assignee: LG CHEM, LTD.
    Inventors: Jae Keun Yoon, Dong Hyun Cho, Sung Jin Kim, Kyung Yeon Kang
  • Publication number: 20210214227
    Abstract: The present invention relates to a method for preparing carbon nanotubes, the method including: preparing a support including AlO(OH) by primary heat treatment of Al(OH)3; preparing an active carrier by supporting a mixture including a main catalyst precursor and a cocatalyst precursor on the support; drying the active carrier through multi-stage drying including vacuum drying; preparing a supported catalyst by secondary heat treatment of the dried active support; and preparing carbon nanotubes in the presence of the supported catalyst, and the carbon nanotubes prepared by the method as described above can remarkably improve conductivity.
    Type: Application
    Filed: July 22, 2019
    Publication date: July 15, 2021
    Inventors: Kyung Yeon KANG, Hyung Joon KANG, Ki Soo KEE
  • Patent number: 11059009
    Abstract: The apparatus for manufacturing carbon nanotube pellets according to the present invention provides carbon nanotube pellets with increased apparent density by using only a small amount of solvent. The carbon nanotube pellets produced by the apparatus according to the present invention can improve various problems generated by scattering of powders. And since the density of the pellet form is high, transport, transfer and improvement become easier. Therefore, it can be more effectively applied to the manufacturing of composite materials.
    Type: Grant
    Filed: October 17, 2016
    Date of Patent: July 13, 2021
    Assignee: LG CHEM, LTD.
    Inventors: Kyung Yeon Kang, Jihee Woo, Seungyong Lee, Hyungsik Jang, Dong Hyun Cho
  • Patent number: 11050061
    Abstract: The present invention provides: a conductive material dispersed liquid containing a conductive material, a dispersant, and a dispersion medium, wherein the conductive material comprises bundle-type carbon nanotubes having a bulk density in a range of 10-50 kg/m3 and a conductivity satisfying the conditions of Equation 1 below, thereby exhibiting excellent dispersibility and conductivity; and a lithium secondary battery, which is manufactured using the conductive material dispersed liquid and thus can exhibit excellent battery functions, especially, excellent output characteristics at low temperatures: ?X?10 log R??0.6X??[Equation 1] (in Equation 1 above, X is a bulk density of the carbon nanotubes, and R is a powder resistance of the carbon nanotubes under a pressure of 10 to 65 MPa.).
    Type: Grant
    Filed: October 28, 2016
    Date of Patent: June 29, 2021
    Inventors: Ye Lin Kim, Jong Heon Seol, Kyung Yeon Kang, Sang Hoon Choy, Ji Hee Woo, Dong Hyun Cho
  • Publication number: 20210139331
    Abstract: The present invention relates to carbon nanotubes having a pore volume of 0.94 cm3/g or more, and being an entangled type, a method of manufacturing the same, and a positive electrode for a primary battery which comprises the same.
    Type: Application
    Filed: July 26, 2019
    Publication date: May 13, 2021
    Inventors: Kyung Yeon Kang, Hyun Joon Kang, Ki Soo Lee, Soon Ki Jeong
  • Patent number: 10857524
    Abstract: The carbon nanotubes according to the present invention can provide higher conductivity by allowing the BET and crystal size to satisfy the conditions expressed by formula 1 below, and consequently, can improve the conductivity of a carbon composite material containing the carbon nanotubes. Lc×[Specific surface area of CNT (cm2/g)]1/2>80??[Formula 1] wherein, Lc is crystal size measured by X-ray diffraction.
    Type: Grant
    Filed: March 21, 2017
    Date of Patent: December 8, 2020
    Assignee: LG CHEM, LTD.
    Inventors: Kyung Yeon Kang, Yelin Kim, Jihee Woo, Jung Keun Yoo, Dong Hyun Cho
  • Publication number: 20200172401
    Abstract: The present invention relates to a method for preparing a carbon nanotube dispersion, the method including mixing a dispersion solution including a dispersion solvent and a dispersant with carbon nanotubes to prepare carbon nanotube paste, extruding the paste to obtain solid carbon nanotubes, and introducing a second solvent to the solid carbon nanotubes, and homogenizing the carbon nanotubes, wherein the weight ratio of the dispersion solution and the carbon nanotubes is 1:1 to 9:1. According to the present invention, the mixing of a dispersant and carbon nanotubes is increased and the particle size is controlled by a wet method, so that a carbon nanotube dispersion having a viscosity controlled to a low level, excellent resistance properties, and a high concentration, may be provided.
    Type: Application
    Filed: January 21, 2019
    Publication date: June 4, 2020
    Inventors: Kyung Yeon Kang, Seung Yong Lee, Seok Won Kim, Hyun Joon Kang
  • Patent number: 10665890
    Abstract: The present invention provides a conductive material for a secondary battery, and a secondary battery containing the same, the conductive material comprising carbon nanotubes, having a secondary structure in which carbon nanotube units having a diameter of 20-150 nm are entangled, having a ratio of true density to bulk density (TD/BD) of 30-120, having a metal content of 50 ppm or less, and having both excellent dispersibility and high purity, thereby being capable of improving, by increasing the conductivity within an electrode, battery performance, particularly, battery performance at room temperature and low temperature when applied to a battery.
    Type: Grant
    Filed: September 9, 2016
    Date of Patent: May 26, 2020
    Assignee: LG CHEM, LTD.
    Inventors: Kyung Yeon Kang, Jong Heon Seol, Ji Hee Woo, Ye Lin Kim, Dong Hyun Cho, Sang Hoon Choy
  • Patent number: 10647579
    Abstract: The method for producing carbon nanotube pellets according to the present invention can reduce the particle size of the carbon nanotubes contained in the pellet by a repetitive extrusion process to produce pellets having improved dispersion characteristics in a solvent. The present invention can improve the problems of the change of the content generated by scattering of powders and safety issues by using carbon nanotubes in the form of pellet. And since the density of the pellet form is higher than that of the powder form, transport, transfer and improvement become easier. Therefore, it can be more effectively applied to the manufacturing of composite materials.
    Type: Grant
    Filed: October 17, 2016
    Date of Patent: May 12, 2020
    Assignee: LG CHEM, LTD.
    Inventors: Kyung Yeon Kang, Jihee Woo, Seungyong Lee, Hyungsik Jang, Dong Hyun Cho
  • Patent number: 10541067
    Abstract: The carbon nanotube pellets according to the present invention are produced by using only a small amount of solvent and have increased apparent density. The present invention can improve the problems of the change of the content generated by scattering of powders and safety issues by using carbon nanotubes in the form of pellet rather than carbon nanotubes in the form of powder in composite materials. And since the density of the pellet form is higher than that of the powder form, transport, transfer and improvement become easier. Therefore, it can be more effectively applied to the manufacturing of composite materials.
    Type: Grant
    Filed: October 17, 2016
    Date of Patent: January 21, 2020
    Assignee: LG CHEM, LTD.
    Inventors: Kyung Yeon Kang, Yelin Kim, Jihee Woo, Seungyong Lee, Hyungsik Jang, Dong Hyun Cho, Sang Hoon Choy
  • Publication number: 20190263663
    Abstract: In the present invention, by dry pulverizing carbon nanotubes to control wettability index of the carbon nanotubes, the maximum concentration of the carbon nanotubes that can be added to the dispersion solvent can be increased and the workability of the carbon nanotube dispersion can be improved. Further, from this, it is possible to more easily predict the maximum concentration of the carbon nanotubes that can be added to the dispersion solvent.
    Type: Application
    Filed: January 5, 2018
    Publication date: August 29, 2019
    Inventors: Jae Keun YOON, Dong Hyun CHO, Sung Jin KIM, Kyung Yeon KANG
  • Publication number: 20190135634
    Abstract: The method for producing carbon nanotube pellets according to the present invention can reduce the particle size of the carbon nanotubes contained in the pellet by a repetitive extrusion process to produce pellets having improved dispersion characteristics in a solvent. The present invention can improve the problems of the change of the content generated by scattering of powders and safety issues by using carbon nanotubes in the form of pellet. And since the density of the pellet form is higher than that of the powder form, transport, transfer and improvement become easier. Therefore, it can be more effectively applied to the manufacturing of composite materials.
    Type: Application
    Filed: October 17, 2016
    Publication date: May 9, 2019
    Applicant: LG Chem, Ltd.
    Inventors: Kyung Yeon KANG, Jihee WOO, Seungyong LEE, Hyungsik JANG, Dong Hyun CHO
  • Publication number: 20190060878
    Abstract: The carbon nanotubes according to the present invention can provide higher conductivity by allowing the BET and crystal size to satisfy the conditions expressed by formula 1 below, and consequently, can improve the conductivity of a carbon composite material containing the carbon nanotubes. Lc×[Specific surface area of CNT (cm2/g)]1/2>80??[Formula 1] wherein, Lc is crystal size measured by X-ray diffraction.
    Type: Application
    Filed: March 21, 2017
    Publication date: February 28, 2019
    Inventors: Kyung Yeon KANG, Yelin KIM, Jihee WOO, Jung Keun YOO, Dong Hyun CHO
  • Publication number: 20180240567
    Abstract: The carbon nanotube pellets according to the present invention are produced by using only a small amount of solvent and have increased apparent density. The present invention can improve the problems of the change of the content generated by scattering of powders and safety issues by using carbon nanotubes in the form of pellet rather than carbon nanotubes in the form of powder in composite materials. And since the density of the pellet form is higher than that of the powder form, transport, transfer and improvement become easier. Therefore, it can be more effectively applied to the manufacturing of composite materials.
    Type: Application
    Filed: October 17, 2016
    Publication date: August 23, 2018
    Inventors: Kyung Yeon KANG, Yelin KIM, Jihee WOO, Seungyong LEE, Hyungsik JANG, Dong Hyun CHO, Sang Hoon CHOY
  • Publication number: 20180198129
    Abstract: The present invention provides: a conductive material dispersed liquid containing a conductive material, a dispersant, and a dispersion medium, wherein the conductive material comprises bundle-type carbon nanotubes having a bulk density in a range of 10-50 kg/m3 and a conductivity satisfying the conditions of Equation 1 below, thereby exhibiting excellent dispersibility and conductivity; and a lithium secondary battery, which is manufactured using the conductive material dispersed liquid and thus can exhibit excellent battery functions, especially, excellent output characteristics at low temperatures: ?X?10 log R??0.6X??[Equation 1] (in Equation 1 above, X is a bulk density of the carbon nanotubes, and R is a powder resistance of the carbon nanotubes under a pressure of 10 to 65 MPa.).
    Type: Application
    Filed: October 28, 2016
    Publication date: July 12, 2018
    Applicant: LG Chem, Ltd.
    Inventors: Ye Lin Kim, Jong Heon Seol, Kyung Yeon Kang, Sang Hoon Choy, Ji Hee Woo, Dong Hyun Cho
  • Publication number: 20180175439
    Abstract: The present invention provides a conductive material for a secondary battery, and a secondary battery containing the same, the conductive material comprising carbon nanotubes, having a secondary structure in which carbon nanotube units having a diameter of 20-150 nm are entangled, having a ratio of true density to bulk density (TD/BD) of 30-120, having a metal content of 50 ppm or less, and having both excellent dispersibility and high purity, thereby being capable of improving, by increasing the conductivity within an electrode, battery performance, particularly, battery performance at room temperature and low temperature when applied to a battery.
    Type: Application
    Filed: September 9, 2016
    Publication date: June 21, 2018
    Inventors: Kyung Yeon KANG, Jong Heon SEOL, Ji Hee WOO, Ye Lin KIM, Dong Hyun CHO, Sang Hoon CHOY
  • Publication number: 20180126350
    Abstract: The apparatus for manufacturing carbon nanotube pellets according to the present invention provides carbon nanotube pellets with increased apparent density by using only a small amount of solvent. The carbon nanotube pellets produced by the apparatus according to the present invention can improve various problems generated by scattering of powders. And since the density of the pellet form is high, transport, transfer and improvement become easier. Therefore, it can be more effectively applied to the manufacturing of composite materials.
    Type: Application
    Filed: October 17, 2016
    Publication date: May 10, 2018
    Inventors: Kyung Yeon KANG, Jihee WOO, Seungyong LEE, Hyungsik JANG, Dong Hyun CHO