# US 12,113,163 B2 · Method of using an electric field for roll-to-roll separator coating > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,113,163 B2 - Document ID: US12113163B2 - Status: Granted - Kind: B2 - Application number: 17/506,446 - Filed: 2021-10-20 - Published: 2023-04-20 - Granted: 2024-10-08 - Earliest claimed: 2021-10-20 - Assignees: GM Global Technology Operations LLC - Applicants: GM Global Technology Operations LLC - Inventors: Ruchira Dharmasena; Shuru Chen; Fang Dai; Mei Cai; Sanaz Ketabi - Web page: https://patentgrep.com/patent/US12113163B2 ## CPC - H01M 10/0404: {Machines for assembling batteries} - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - H01M 50/403: Manufacturing processes of separators, membranes or diaphragms - H01M 50/406: Moulding; Embossing; Cutting - H01M 50/414: Synthetic resins, e.g. thermoplastics or thermosetting resins - H01M 50/417: Polyolefins - H01M 50/431: Inorganic material - H01M 50/434: Ceramics - H01M 50/446: Composite material consisting of a mixture of organic and inorganic materials - H01M 50/449: having a layered structure - H01M 50/451: comprising layers of only organic material and layers containing inorganic material - H01M 50/457: comprising three or more layers - H01M 50/46: Separators, membranes or diaphragms characterised by their combination with electrodes - 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 system for coating a separator for a battery includes a separator feed and collection assembly configured to dispense the separator, a coating distribution device configured to flow a coating material toward the separator, and an electric field generator configured to generate an electric field in a gap between the coating distribution device and the separator. ## Claims ### Claim 1 A system for coating a separator for a battery, the system comprising: a separator feed and collection assembly configured to dispense the separator; a coating distribution device configured to flow a coating material toward the separator; and an electric field generator configured to generate an electric field in a gap between the coating distribution device and the separator, wherein the coating material includes a metal oxide and carbon. ### Claim 2 (depends on 1) The system of claim 1, wherein the separator feed and collection assembly includes a spool assembly, and wherein the spool assembly comprises: a source spool configured to hold the separator prior to being coated with the coating material; a collector spool configured to hold the separator subsequent to being coated with the coating material; and a coating drum arranged between the source spool and the collector spool, wherein the coating drum is configured to hold the separator while the separator is coated with the coating material. ### Claim 3 (depends on 2) The system of claim 2, wherein the electric field generator is configured to negatively charge the coating drum to generate the electric field. ### Claim 4 (depends on 1) The system of claim 1, wherein the electric field generator includes a power supply connected to the coating distribution device and the separator feed and collection assembly. ### Claim 5 (depends on 4) The system of claim 4, wherein the power supply includes a positive terminal connected to the coating distribution device and a negative terminal connected to a coating drum of the separator feed and collection assembly. ### Claim 6 (depends on 4) The system of claim 4, wherein the power supply is configured to generate at least a 3 kV/m electric field. ### Claim 7 (depends on 1) The system of claim 1, wherein the coating distribution device includes a syringe configured to flow the coating material into the gap. ### Claim 8 (depends on 7) The system of claim 7, wherein the syringe is configured to flow the coating material at between 0 and 1 microliters per minute. ### Claim 9 (depends on 1) The system of claim 1, wherein the coating material includes the metal oxide and carbon dissolved in a polymer solution. ### Claim 10 (depends on 9) The system of claim 9, wherein the metal oxide includes titanium dioxide. ### Claim 11 (depends on 9) The system of claim 9, wherein the electric field generator is configured to charge particles of the metal oxide and the carbon. ### Claim 12 (depends on 1) The system of claim 1, further comprising a coating control module to control a rate of movement of the separator through the separator feed and collection assembly, a flow rate of the coating material from the coating distribution device, and the generation of the electric field such that the coating material is applied to the separator at a thickness between 2 and 20 μm. ### Claim 13 A method for coating a separator for a battery, the method comprising: using a separator feed and collection assembly, dispensing the separator at a controlled movement rate; flowing a coating material from a coating distribution device toward the separator; and generating an electric field in a gap between the coating distribution device and the separator, wherein the coating material includes a metal oxide and carbon. ### Claim 14 (depends on 13) The method of claim 13, further comprising generating the electric field using a power supply connected to the coating distribution device and the separator feed and collection assembly. ### Claim 15 (depends on 14) The method of claim 14, further comprising connecting a positive terminal of the power supply to the coating distribution device and a negative terminal of the power supply to a coating drum of the separator feed and collection assembly. ### Claim 16 (depends on 13) The method of claim 13, wherein the electric field is at least 3 kV/m. ### Claim 17 (depends on 13) The method of claim 13, further comprising flowing the coating material into the gap using a syringe. ### Claim 18 (depends on 13) The method of claim 13, wherein the metal oxide and carbon is dissolved in a polymer solution. ### Claim 19 (depends on 18) The method of claim 18, further comprising controlling the movement rate of the separator, a flow rate of the coating material from the coating distribution device, and the generation of the electric field such that the coating material is applied to the separator at a thickness between 2 and 20 μm. ### Claim 20 A system for coating a separator for a battery, the system comprising: a separator feed and collection assembly configured to dispense the separator; a coating distribution device configured to flow a coating material toward the separator; an electric field generator configured to generate an electric field in a gap between the coating distribution device and the separator; and a coating control module to control a rate of movement of the separator through the separator feed and collection assembly, a flow rate of the coating material from the coating distribution device, and the generation of the electric field such that the coating material is applied to the separator at a thickness between 2 and 20 μm.