# US 10,873,117 B2 · Multi-layer structures prepared by layer-by-layer assembly > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,873,117 B2 - Document ID: US10873117B2 - Status: Granted - Kind: B2 - Application number: 14/143,803 - Filed: 2013-12-30 - Published: 2014-07-03 - Granted: 2020-12-22 - Earliest claimed: 2013-01-01 - Assignees: Massachusetts Institute of Technology - Applicants: Massachusetts Institute of Technology - Inventors: Paula T. Hammond; Sun Hwa Lee - Web page: https://patentgrep.com/patent/US10873117B2 ## CPC - H01M 12/08: composed of a half-cell of a fuel-cell type and a half-cell of the secondary-cell type - H01M 4/134: Electrodes based on metals, Si or alloys - H01M 4/382: {Lithium (H01M4/405 takes precedence)} - H01M 4/62: Selection of inactive substances as ingredients for active masses, e.g. binders, fillers - H01M 50/417: Polyolefins - H01M 50/437: Glass - H01M 50/457: comprising three or more layers - H01M 50/46: Separators, membranes or diaphragms characterised by their combination with electrodes - H01M 4/628: {Inhibitors, e.g. gassing inhibitors, corrosion inhibitors} - H01M 50/489: Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties - H01M 50/497: Ionic conductivity - H01M 2300/0082: Organic polymers - H01M 2300/0094: in the form of layered products, e.g. coatings - 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 A protective layer can be deposited on a surface of an porous polymer separator placing on a Li-metal electrode to protect against adverse electrochemical activity in a battery. The protective layer can be a multilayered structure including graphene oxide. ## Claims ### Claim 1 A method of preparing a multi-layer structure on a substrate comprising: forming a pair of bilayers on a surface of the substrate in a layer-by-layer assembly by contacting the substrate with a solution with sequential adsorption of materials in each layer, the first bilayer including a first material and a second material, the first and second material having complementary functional groups; the second bilayer including a third material and a fourth material, the third and fourth material having complementary functional groups; and the pair of bilayers includes an ion-conductive polymer layer, a polyanion or polycation, and a graphene oxide barrier layer substantially free of graphene. ### Claim 2 (depends on 1) The method of claim 1, wherein the substrate includes a membrane and preparing the multi-layer structure further comprises: contacting the membrane with a first solution containing the first material; contacting the membrane having the first material with a second solution containing the second material; contacting the membrane having the first and second material with a third solution containing the third material; and contacting the membrane having the first, second and third material with a fourth solution containing the fourth material. ### Claim 3 (depends on 2) The method of claim 2, wherein pH of the first solution, the second solution, the third solution, and the fourth solution is adjusted for hydrogen bonding between materials in the bilayers. ### Claim 4 (depends on 2) The method of claim 2, wherein lithium bis(oxalate)borate is dissolved in the first solution. ### Claim 5 (depends on 2) The method of claim 2, wherein lithium bis(oxalate)borate is dissolved in the second solution. ### Claim 6 (depends on 2) The method of claim 2, wherein lithium bis(oxalate)borate is dissolved in the third solution. ### Claim 7 (depends on 2) The method of claim 2, wherein lithium bis(oxalate)borate is dissolved in the fourth solution. ### Claim 8 (depends on 2) The method of claim 2, wherein the first solution includes polyethylene oxide, graphene oxide, or polyacrylic acid. ### Claim 9 (depends on 2) The method of claim 2, wherein the second solution includes polyethylene oxide, graphene oxide, or polyacrylic acid. ### Claim 10 (depends on 2) The method of claim 2, wherein the third solution includes polyethylene oxide, graphene oxide, or polyacrylic acid. ### Claim 11 (depends on 2) The method of claim 2, wherein the fourth solution includes polyethylene oxide, graphene oxide, or polyacrylic acid. ### Claim 12 (depends on 1) The method of claim 1, wherein the first material and the third material are the same. ### Claim 13 (depends on 1) The method of claim 1, wherein the first material and the third material are different. ### Claim 14 (depends on 1) The method of claim 1, wherein the second material and the fourth material are the same. ### Claim 15 (depends on 1) The method of claim 1, wherein the second material and the fourth material are different. ### Claim 16 (depends on 1) The method of claim 1, wherein the substrate includes a membrane. ### Claim 17 (depends on 16) The method of claim 16, wherein the membrane includes polypropylene. ### Claim 18 (depends on 1) The method of claim 1, wherein the substrate is plasma treated. ### Claim 19 (depends on 1) The method of claim 1, wherein the substrate is glass. ### Claim 20 (depends on 1) The method of claim 1, wherein the first material is polyethylene oxide, the second material is graphene oxide, the third material is polyethylene oxide, and the fourth material is polyacrylic acid. ### Claim 21 (depends on 20) The method of claim 20, wherein the pair of bilayers is formed on a polypropylene membrane.