# US 2021/0242442 A1 · Functionalized separator having zwitterionic coating and method of fabricating thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242442 A1 - Document ID: US20210242442A1 - Status: Published application - Kind: A1 - Application number: 16/989,986 - Filed: 2020-08-11 - Published: 2021-08-05 - Earliest claimed: 2020-01-31 - Assignees: Research & Business Foundation Sungkyunkwan University - Applicants: Research & Business Foundation Sungkyunkwan University - Inventors: Pil Jin YOO; Ho Seok PARK; Duk Joon KIM; Jun Hyuk LEE; Jeong Seok YEON; Sung Mo KANG - Web page: https://patentgrep.com/patent/US20210242442A1 ## CPC - H01M 50/446: Composite material consisting of a mixture of organic and inorganic materials - H01M 50/403: Manufacturing processes of separators, membranes or diaphragms - H01M 50/411: Organic material - H01M 50/437: Glass - H01M 50/451: comprising layers of only organic material and layers containing inorganic material - Y02E 60/10: Energy storage using batteries - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract Disclosed is a method for manufacturing a functionalized separator having a zwitterionic coating thereon. The method includes preparing a porous separator; coating a linker on a surface of the porous separator; and chemically reacting zwitterions with the linker such the zwitterions are grafted to the linker on the surface of the separator. The zwitterions grafted to the linker acts as a monolayer to functionalize the surface of the separator. The functionalized separator may disallow elution of polysulfide compound in a lithium-sulfur battery. Further, the functionalized separator may increase ion conductivity of electrolyte of the lithium-sulfur battery and thus ensure high output characteristics. ## Claims ### Claim 1 A method for manufacturing a functionalized separator having a zwitterionic coating thereon, the method comprising: preparing a porous separator; coating a linker on a surface of the porous separator; and chemically reacting zwitterions with the linker such the zwitterions are grafted to the linker on the surface of the separator, wherein the zwitterions grafted to the linker acts as a monolayer to functionalize the surface of the separator. ### Claim 2 (depends on 1) The method of claim 1, wherein the porous separator includes a polymer separator. ### Claim 3 (depends on 1) The method of claim 1, wherein the porous separator includes an inorganic separator. ### Claim 4 (depends on 1) The method of claim 1, wherein the linker contains an amine group. ### Claim 5 (depends on 1) The method of claim 1, wherein a zwitterionic monomer containing the zwitterions reacts with the linker, wherein the zwitterionic monomer containing the zwitterions has a cationic functional group and an anionic functional group at one end thereof and an acrylate functional group at the other end thereof. ### Claim 6 (depends on 4) The method of claim 4, wherein a zwitterionic monomer containing the zwitterions reacts with the linker, wherein the zwitterionic monomer containing the zwitterions has a cationic functional group and an anionic functional group at one end thereof and an acrylate functional group at the other end thereof. ### Claim 7 (depends on 6) The method of claim 6, wherein the zwitterionic monomer includes [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide or 2-methacryloyloxyethyl phosphorylcholine. ### Claim 8 (depends on 6) The method of claim 6, wherein the chemically reacting of the zwitterions with the linker includes formation of a bond via an addition reaction between the amine group of the linker and the acrylate functional group of the zwitterionic monomer. ### Claim 9 (depends on 1) A functionalized separator having a zwitterionic coating thereon, wherein the functionalized separator is manufactured using the method of claim 1, wherein the functionalized separator is used as a separator for a lithium-sulfur battery. ### Claim 10 A functionalized separator having a zwitterionic coating thereon, wherein the functionalized separator includes a porous separator, wherein zwitterions are coated on a surface of the porous separator, wherein the zwitterionic coating acts as a monolayer to functionalize the surface of the porous separator. ### Claim 11 (depends on 10) The functionalized separator of claim 10, wherein a linker is coated on the surface of the porous separator, and the zwitterions are grafted to the linker on the surface of the porous separator. ### Claim 12 (depends on 10) The functionalized separator of claim 10, wherein the porous separator includes a polymer separator. ### Claim 13 (depends on 10) The functionalized separator of claim 10, wherein the porous separator includes an inorganic separator. ### Claim 14 (depends on 11) The functionalized separator of claim 11, wherein the linker contains an amine group. ### Claim 15 (depends on 10) The functionalized separator of claim 10, wherein in order that the zwitterions are coated on the surface of the porous separator, a zwitterionic monomer containing the zwitterions reacts with the surface of the porous separator, wherein the zwitterionic monomer containing the zwitterions has a cationic functional group and an anionic functional group at one end thereof and an acrylate functional group at the other end thereof. ### Claim 16 (depends on 14) The functionalized separator of claim 14, wherein in order that the zwitterions are coated on the surface of the porous separator, a zwitterionic monomer containing the zwitterions reacts with the linker coated on the surface of the porous separator, wherein the zwitterionic monomer containing the zwitterions has a cationic functional group and an anionic functional group at one end thereof and an acrylate functional group at the other end thereof. ### Claim 17 (depends on 16) The functionalized separator of claim 16, wherein the zwitterionic monomer includes [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide or 2-methacryloyloxyethyl phosphorylcholine. ### Claim 18 (depends on 16) The functionalized separator of claim 16, wherein when the zwitterionic monomer containing the zwitterions reacts with the linker coated on the surface of the porous separator, a bond is formed via an addition reaction between the amine group of the linker and the acrylate functional group of the zwitterionic monomer, such that the zwitterions are grafted onto the linker. ### Claim 19 (depends on 10) The functionalized separator of claim 10, wherein the functionalized separator is used as a separator for a lithium-sulfur battery.