Patents by Inventor Sang-hoon Choy

Sang-hoon Choy 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: 20210043938
    Abstract: Provided is a positive electrode slurry for preparing a positive electrode for a lithium secondary battery, the positive electrode slurry including a positive electrode active material, a conductive material, a binder, overcharge inhibitor, oxalic acid, and a solvent, wherein the overcharge inhibitor is included in an amount of 1 part by weight to 2 parts by weight, based on 100 parts by weight of the total solid content of the positive electrode active material, the conductive material, and the binder of the positive electrode slurry, the oxalic acid is included in an amount of 0.1 part by weight to 0.7 parts by weight, based on 100 parts by weight of the total solid content of the positive electrode active material, the conductive material, and the binder of the positive electrode slurry, and the positive electrode slurry has a viscosity of 4000 cp to 15000 cp at room temperature.
    Type: Application
    Filed: December 4, 2019
    Publication date: February 11, 2021
    Applicant: LG CHEM, LTD.
    Inventors: Shanghao PIAO, Hye Lim SHIM, Wooha KIM, Sang Hoon CHOY
  • Publication number: 20210013487
    Abstract: The present invention relates to a method of preparing a positive electrode which includes forming a solid electrolyte by mixing a lithium salt and a polymer for a solid electrolyte in a dry atmosphere, forming a dry mixture by stirring after adding a conductive agent and a positive electrode active material to the solid electrolyte in a dry atmosphere, and pressing after coating a current collector with the dry mixture.
    Type: Application
    Filed: March 14, 2019
    Publication date: January 14, 2021
    Applicant: LG Chem, Ltd.
    Inventors: Chang Wan Koo, Ki Tae Kim, Sang Hoon Choy
  • Patent number: 10888870
    Abstract: The present invention relates to a grinder using induced electric fields. The grinder comprises: a grinding unit on which a plurality of protrusions for cutting are disposed on an outer circumferential surface thereof; a power unit disposed in the grinding unit to generate electric fields and attach the conductive materials to the grinding unit; and a chamber disposed outside the grinding unit and comprising beads that disperse and grind the conductive materials attached to the grinding unit, wherein the conductive materials have directionality by the electric fields of the power unit.
    Type: Grant
    Filed: March 17, 2017
    Date of Patent: January 12, 2021
    Inventors: Jin Young Son, Hyung Suk Cho, Sang Hoon Choy, Byoung Hoon Ahn, Hyun Sik Chae
  • Publication number: 20200386663
    Abstract: The present invention relates to a method for measuring undissolved material in a polymer solution used in the production of electrode slurry using a surface light source. The method for measuring undissolved material in a polymer solution of the present invention comprises: a solution application step of applying a polymer solution on a transparent plate; a light supplying step of supplying light with a light source to the polymer solution applied on the transparent plate; a photographing step of photographing a shape of the light transmitted through the polymer solution applied on the transparent plate; and a measuring step of confirming the number and particle size of the undissolved material in the polymer solution with a photographed image.
    Type: Application
    Filed: July 31, 2019
    Publication date: December 10, 2020
    Applicant: LG CHEM, LTD.
    Inventors: Hwi Soo YANG, Ga Hyun LIM, Sang Hoon CHOY
  • Publication number: 20200373559
    Abstract: A positive electrode includes a current collector and a positive electrode active material layer disposed on the current collector, wherein the positive electrode active material layer includes a positive electrode active material, carbon nanotube, and a binder, the binder includes polyvinylidene fluoride which has a weight average molecular weight of 720,000 g/mol to 980,000 g/mol, a BET specific surface area of the carbon nanotube is 140 m2/g to 195 m2/g, and the positive electrode satisfies the following Formula 1: 1.3?B/A?3.4??[Formula 1] in Formula 1, B is an amount (wt %) of the polyvinylidene fluoride in the positive electrode active material layer, and A is an amount (wt %) of the carbon nanotube in the positive electrode active material layer.
    Type: Application
    Filed: February 19, 2019
    Publication date: November 26, 2020
    Applicant: LG Chem, Ltd.
    Inventors: Joo Yul Baek, Jun Muk Lim, Chang Ju Lee, Il Geun Oh, Je Young Kim, Sang Hoon Choy
  • Publication number: 20200358103
    Abstract: A secondary battery includes a positive electrode, a negative electrode, a separator disposed between the positive electrode and the negative electrode, and an electrolyte solution, wherein the positive electrode includes a current collector and a positive electrode active material layer disposed on the current collector, the positive electrode active material layer includes a positive electrode active material and carbon nanotubes, and the electrolyte solution includes a non-aqueous solvent, a lithium salt, and tetravinylsilane.
    Type: Application
    Filed: February 22, 2019
    Publication date: November 12, 2020
    Applicant: LG Chem, Ltd.
    Inventors: Joo Yul Baek, Young Min Lim, Jun Muk Lim, Sang Hoon Choy, Chul Haeng Lee
  • Patent number: 10822498
    Abstract: The present disclosure relates to a carbon black dispersion solution comprising carbon black, a dispersion medium, and partially hydrogenated nitrile rubber having a residual double bond (RDB) value of 0.5% by weight to 40% by weight calculated according to the following Mathematical Formula 1, wherein dispersed particle diameters of the carbon black have particle size distribution D50 of 0.1 ?m to 2 ?m, a method for preparing the same, and methods for preparing electrode slurry and an electrode using the same.
    Type: Grant
    Filed: August 26, 2016
    Date of Patent: November 3, 2020
    Assignee: LG Chem, Ltd.
    Inventors: Gyemin Kwon, Houngsik Yoo, Hye Lim Sim, Byoung Hoon Ahn, Jong Won Lee, Dong Hyun Kim, Sang Hoon Choy, Hyeon Choi
  • Publication number: 20200331759
    Abstract: A method of preparing graphene, including preparing graphite; and putting the graphite in the inside of a vessel and applying vibration at a frequency of 55 Hz to 65 Hz to the vessel.
    Type: Application
    Filed: April 10, 2018
    Publication date: October 22, 2020
    Applicant: LG Chem, Ltd.
    Inventors: Jin Young Son, Cheol Woo Kim, Byoung Hoon Ahn, Hyun Sik Chae, Sang Hoon Choy
  • Patent number: 10804528
    Abstract: Disclosed is a method for preparing positive electrode active material slurry, which includes the steps of: (S1) preparing a positive electrode active material, a linear conductive material, a polymer binder and a solvent; (S2) introducing 40-80% of the prepared polymer binder, the positive electrode active material and the linear conductive material to the solvent, followed by mixing, to obtain a first positive electrode active material slurry; and (S3) further introducing the remaining polymer binder to the first positive electrode active material slurry, followed by mixing, to obtain a second positive electrode active material slurry.
    Type: Grant
    Filed: November 16, 2017
    Date of Patent: October 13, 2020
    Assignee: LG Chem, Ltd.
    Inventors: Byoung-Hoon Ahn, Sang-Hoon Choy, Hyun-Sik Chae
  • Publication number: 20200321599
    Abstract: The present invention provides a method for manufacturing an electrode, the method comprising the steps of: preparing a lump of mixture bulk; milling the mixture bulk to prepare granular powder having an average particle diameter of 30 micrometers to 180 micrometers; sprinkling the granular powder on the surface of a metal current collector; and rolling the granular powder on the metal current collector to laminate the granular powder on the metal current collector.
    Type: Application
    Filed: September 21, 2018
    Publication date: October 8, 2020
    Applicant: LG Chem, Ltd.
    Inventors: Ki Tae Kim, Chang Wan Koo, Sang Hoon Choy
  • Publication number: 20200295347
    Abstract: A method of preparing a slurry composition for a secondary battery positive electrode includes preparing a positive electrode active material pre-dispersion by mixing a lithium iron phosphate-based positive electrode active material, a dispersant, and a solvent, and preparing a slurry for a positive electrode by further mixing a conductive agent, a binder, and an additional solvent with the positive electrode active material pre-dispersion is provided. A positive electrode for a secondary battery which is prepared by using the same method, and a lithium secondary battery including the positive electrode are also provided.
    Type: Application
    Filed: March 22, 2018
    Publication date: September 17, 2020
    Applicant: LG Chem, Ltd.
    Inventors: Byoung Hoon Ahn, Houng Sik Yoo, Gye Min Kwon, Sang Hoon Choy
  • Patent number: 10741829
    Abstract: The present invention provides a composition for forming a positive electrode of a secondary battery which includes a positive electrode active material, a conductive material, and a dispersing agent, in which the conductive material includes a carbon-based material having a specific surface area of 130 m2/g or more and an oil absorption number of 220 ml/100 g or more at 0.1 wt % to 2 wt % with respect to the total weight of the composition for forming a positive electrode, and the dispersing agent is introduced into the conductive material to form a conductive material-dispersing agent composite, and the conductive material-dispersing agent composite has a particle size distribution D50 of 0.8 ?m to 1.2 ?m, a positive electrode for a secondary battery and a secondary battery, which are manufactured using the same.
    Type: Grant
    Filed: March 24, 2017
    Date of Patent: August 11, 2020
    Assignee: LG Chem, Ltd.
    Inventors: Byoung Hoon Ahn, Sang Hoon Choy, Houng Sik Yoo, Ki Won Sung
  • Publication number: 20200240915
    Abstract: The present invention relates to an apparatus and method for monitoring a dry state of an electrode substrate in which electrode slurry is applied to a collector. The monitoring method comprises emitting light onto a surface of the electrode substrate; receiving the light reflected by the surface of the electrode substrate; and analyzing a luminous intensity or spectrum of the received light to estimate a drying rate of the electrode substrate. The apparatus includes a light emitting part emitting light from a light source onto a surface of the electrode substrate; a light receiving part receiving the light reflected by the surface of the electrode substrate; and a computing device analyzing a luminous intensity or spectrum of the received light and comparing analyzed characteristics of the light with the reference data of the reflected light to the drying rate of the electrode substrate.
    Type: Application
    Filed: December 17, 2018
    Publication date: July 30, 2020
    Applicant: LG Chem, Ltd.
    Inventors: Jin Young Son, Moo Yong Shin, Taek Soo Lee, Cheol Woo Kim, Sang Hoon Choy
  • Patent number: 10727477
    Abstract: The present invention provides a conductive material dispersed liquid, including: a conductive material which includes bundle-type carbon nanotubes; a dispersant; a dispersion medium, where a phase angle is in a range of 3° to 18° when measured by a rheometer at a frequency of 1 Hz; and a lithium secondary battery manufactured using the conductive material dispersed liquid. The conductive material dispersed liquid has high solid-like properties, and thus allows the formation of an electrode active material layer having a uniform thickness with no concern for collapse or occurrence of cracks during manufacture of an electrode, and thereby can improve the performance characteristics, particularly capacity characteristics, of a battery.
    Type: Grant
    Filed: October 28, 2016
    Date of Patent: July 28, 2020
    Assignee: LG Chem, Ltd.
    Inventors: Ye Lin Kim, Ki Yeon Jo, Jung Keun Yoo, Je Young Kim, Sang Hoon Choy, Jong Heon Seol
  • Publication number: 20200227719
    Abstract: Disclosed is a coating apparatus for producing an electrode, which has a reduced defect rate in the coating process. The coating apparatus includes a die unit having an inlet through which the electrode slurry is introduced and an inner space for accommodating the introduced electrode slurry; a shim unit mounted in the die unit and configured to form an outlet together with the die unit so that the electrode slurry is discharged therethrough; and a cover member configured to surround an outer surface of the die unit and the shim unit so that the electrode slurry is not leaked at the outer surface, except for the outlet.
    Type: Application
    Filed: June 27, 2018
    Publication date: July 16, 2020
    Applicant: LG Chem, Ltd.
    Inventors: Woo-Ha Kim, In-Seong Kim, Il-Jae Moon, Byoung-Hoon Ahn, Jung-Min Yang, Sang-Hoon Choy
  • Publication number: 20200212430
    Abstract: A method for evaluating phase stability of an electrode mixture slurry, including the steps of: (S1) introducing the electrode mixture slurry to a rheometer; (S2) applying a first shear rate to the electrode mixture slurry; (S3) applying a second shear rate after applying the first shear rate to the electrode mixture slurry, wherein the second shear rate is higher than the first shear rate; (S4) applying a third shear rate after applying the second shear rate to the electrode mixture slurry, wherein the third shear rate is lower than the second shear rate; and (S5) comparing the shear viscosity at the first shear rate with the shear viscosity at the third shear rate. An apparatus for evaluating phase stability of the electrode mixture slurry is also provided.
    Type: Application
    Filed: February 22, 2019
    Publication date: July 2, 2020
    Applicant: LG CHEM, LTD.
    Inventors: Ga-Hyun LIM, Jin-Young SON, Hwi-Soo YANG, Jong-Heon SEOL, Hyung-Suk CHO, Sang-Hoon CHOY
  • Patent number: 10693124
    Abstract: The present invention provides a composition for forming a positive electrode of a secondary battery which includes a positive electrode active material, a conductive material, and a dispersing agent, in which the conductive material includes a carbon-based material having a specific surface area of 130 m2/g or more and an oil absorption number of 220 ml/100 g or more at 0.1 wt % to 2 wt % with respect to the total weight of the composition for forming a positive electrode, and the dispersing agent is introduced into the conductive material to form a conductive material-dispersing agent composite, and the conductive material-dispersing agent composite has a particle size distribution D50 of 0.8 ?m to 1.2 ?m, a positive electrode for a secondary battery and a secondary battery, which are manufactured using the same.
    Type: Grant
    Filed: March 24, 2017
    Date of Patent: June 23, 2020
    Assignee: LG Chem, Ltd.
    Inventors: Byoung Hoon Ahn, Sang Hoon Choy, Houng Sik Yoo, Ki Won Sung
  • Patent number: 10686185
    Abstract: The present disclosure relates to a carbon nanotube dispersion including entangled-type carbon nanotubes, a dispersion medium, and partially hydrogenated nitrile rubber having a residual double bond (RDB) value of 0.5% by weight to 40% by weight calculated according to the following Mathematical Formula 1, wherein dispersed particle diameters of the carbon nanotubes have particle size distribution D50 of 2 ?m to 5 ?m, a method for preparing the same, and methods for preparing electrode slurry and an electrode using the same.
    Type: Grant
    Filed: August 26, 2016
    Date of Patent: June 16, 2020
    Assignee: LG CHEM, LTD.
    Inventors: Houngsik Yoo, Jong Won Lee, Dong Hyun Kim, Gyemin Kwon, Byoung Hoon Ahn, Yelin Kim, Sang Hoon Choy, Hyeon Choi, Jungkeun Yoo
  • Publication number: 20200185696
    Abstract: The present invention relates to an electrode slurry coating apparatus comprising a lower die applying electrode slurry on a collector, an intermediate die, and an upper die, a first discharge part primarily applying the electrode slurry on the collector to form a first coating layer; an intermediate pressing part pressing the first coating layer to adjust a thickness of the first coating layer; a second discharge part secondarily applying the electrode slurry on a surface of the first coating layer to form a second coating layer; and an upper pressing part pressing the first coating layer and the second coating layer, which are stacked, at the same time to to adjust a thickness of each of the first coating layer and the second coating layer, wherein the first discharge part has a width less than that of the second discharge part.
    Type: Application
    Filed: December 14, 2018
    Publication date: June 11, 2020
    Inventors: Taek Soo Lee, Cheol Woo Kim, Sang Hoon Choy
  • Patent number: 10680247
    Abstract: The present invention relates to positive electrode active material slurry of which degree of non-crystallinity is controlled by including a rubber-based binder in a specific ratio, a positive electrode including a positive electrode active material layer formed therefrom, and a lithium secondary battery including the positive electrode. The positive electrode active material layer formed from the positive electrode active material slurry has enhanced flexibility and rolling property, and internal short circuits, high voltage defects and capacity decline of the lithium secondary battery using the positive electrode including the same are capable of being suppressed.
    Type: Grant
    Filed: October 5, 2018
    Date of Patent: June 9, 2020
    Assignee: LG Chem, Ltd.
    Inventors: Do Hwa Jung, Sang Hoon Choy