# US 2021/0175583 A1 · Separator for lithium secondary battery and lithium secondary battery including same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0175583 A1 - Document ID: US20210175583A1 - Status: Published application - Kind: A1 - Application number: 16/768,468 - Filed: 2019-01-17 - Published: 2021-06-10 - Earliest claimed: 2018-01-18 - Assignees: LG Chem, Ltd. - Applicants: LG Chem, Ltd. - Inventors: Won Kyung SHIN; Kyoung Ho AHN; Chul Haeng LEE - Web page: https://patentgrep.com/patent/US20210175583A1 ## CPC - H01G 11/06: with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC] - H01M 50/414: Synthetic resins, e.g. thermoplastics or thermosetting resins - C08F 220/20: of polyhydric alcohols or phenols {, e.g. 2-hydroxyethyl (meth)acrylate or glycerol mono-(meth)acrylate} - C09D 127/16: Homopolymers or copolymers of vinylidene fluoride - H01G 11/52: Separators - H01M 10/052: Li-accumulators - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - H01M 10/0565: Polymeric materials, e.g. gel-type or solid-type - H01M 50/403: Manufacturing processes of separators, membranes or diaphragms - H01M 50/446: Composite material consisting of a mixture of organic and inorganic materials - H01M 50/451: comprising layers of only organic material and layers containing inorganic material - H01M 50/454: comprising a non-fibrous layer and a fibrous layer superimposed on one another - H01M 50/457: comprising three or more layers - H01M 50/461: {with adhesive layers between electrodes and separators} - C08K 3/22: of metals - C08K 2003/2227: {of aluminium} - H01M 50/417: Polyolefins - H01M 50/426: Fluorocarbon polymers - H01M 2300/0082: Organic polymers - H01M 2300/0085: Immobilising or gelification of electrolyte - H01M 2300/0094: in the form of layered products, e.g. coatings - Y02E 60/10: Energy storage using batteries - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - H01G: CAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE (selection of specified materials as dielectric H01B3/00; capacitors having potential barriers H10D1/62, H10K10/10) - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - C08F: MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS - C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract The present invention relates to a separator for a lithium secondary battery including a substrate, a first coating layer including a first organic binder containing an ethylenically unsaturated group, and a second coating layer including a second organic binder and inorganic particles, a method for preparing the same, and a lithium secondary battery including the separator for a lithium secondary battery. ## Claims ### Claim 1 A separator comprising: a substrate; a first coating layer including a first organic binder containing an ethylenically unsaturated group; and a second coating layer including a second organic binder and inorganic particles. ### Claim 2 (depends on 1) The separator of claim 1, wherein the first coating layer is disposed on a surface of the substrate, and the second coating layer is disposed on the first coating layer. ### Claim 3 (depends on 1) The separator of claim 1, wherein the second coating layer is disposed on a surface of the substrate, and the first coating layer is formed on the second coating layer. ### Claim 4 (depends on 1) The separator of claim 1, wherein the ethylenically unsaturated group comprises at least one selected from the group consisting of a vinyl group, an acryloxy group and a methacryloxy group. ### Claim 5 (depends on 1) The separator of claim 1, wherein the first organic binder and the second organic binder each independently comprise a polymer including at least one unit selected from the group consisting of Formula X-1 to Formula X-6. wherein, in Formula X-1, m1 is an integer of 1 to 100, wherein, in Formula X-2, m2 and m3 are each independently an integer of 1 to 100, wherein, Formula X-3, m4 is an integer of 1 to 100, wherein, in Formula X-4, m5 is an integer of 1 to 100, wherein, in Formula X-5, m6 is an integer of 1 to 100, wherein, in Formula X-6, m7 is an integer of 1 to 100. ### Claim 6 A method for preparing a separator for a lithium secondary battery, the method comprising, forming, on a surface of a substrate, a first coating layer including a first organic binder containing an ethylenically unsaturated group and a second coating layer including a second organic binder and inorganic particles. ### Claim 7 (depends on 6) The method of claim 6, wherein the first coating layer is formed on the substrate, and then a second coating layer is formed on the first coating layer. ### Claim 8 (depends on 6) The method of claim 6, wherein the second coating layer is formed on the substrate, and then a first coating layer is formed on the second coating layer. ### Claim 9 (depends on 6) The method of claim 6, wherein a temperature for forming the first coating layer is 40° C. to 110° C., and a temperature for forming the second coating layer is 120° C. to 200° C. ### Claim 10 A lithium secondary battery comprising: an electrode assembly including: at least one unit cell including at least one positive electrode, at least one negative electrode, and at least one first separator interposed between the positive electrode and the negative electrode; and a second separator interposed between the unit cells; and a gel polymer electrolyte of an oligomer containing a (meth) acrylate group, wherein the first separator and the second separator each comprise: a first coating layer including a first organic binder containing an ethylenically unsaturated group; and a second coating layer including a second organic binder and inorganic particles, and a polymer network in a three-dimensional structure of a polymer of the first organic binder containing an ethylenically unsaturated group and the oligomer containing a (meth) acrylate group. ### Claim 11 (depends on 10) The lithium secondary battery of claim 10, wherein the oligomer is represented by Formula 1 below: A-C1-A′ [Formula 1] wherein, in Formula 1, A and A′ are each independently a unit containing a (meth) acrylate group, and C1 is a unit containing an oxyalkylene group. ### Claim 12 (depends on 10) The lithium secondary battery of claim 10, wherein the oligomer comprises at least one compound selected from the group consisting of the compounds represented by Formula 1-1 to Formula 1-5 below: wherein, in Formula 1-1, n1 is an integer of 1 to 20,000, wherein, in Formula 1-2, n2 is an integer of 1 to 20,000, wherein, in Formula 1-3, n3 is an integer of 1 to 20,000, wherein, in Formula 1-4, n4 is an integer of 1 to 20,000, wherein, in Formula 1-5, n5 is an integer of 1 to 20,000. ### Claim 13 (depends on 10) The lithium secondary battery of claim 10, wherein the gel polymer electrolyte is formed by injecting a gel polymer electrolyte composition including the oligomer into a battery case and then curing the composition.