# US 12,002,923 B2 · Intumescent battery pad > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,002,923 B2 - Document ID: US12002923B2 - Status: Granted - Kind: B2 - Application number: 16/892,566 - Filed: 2020-06-04 - Published: 2020-12-10 - Granted: 2024-06-04 - Earliest claimed: 2019-06-10 - Assignees: Rogers Corporation - Applicants: Rogers Corporation - Inventors: Wei Wang; Brett Kilhenny; Robert Daigle; Mark St. Jean; Christopher Churchill - Web page: https://patentgrep.com/patent/US12002923B2 ## CPC - H01M 10/0525: Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries - H01M 10/6235: Power tools - H01M 10/052: Li-accumulators - H01M 10/658: by thermal insulation or shielding - H01M 10/659: by heat storage or buffering, e.g. heat capacity or liquid-solid phase changes or transition - H01M 50/209: adapted for prismatic or rectangular cells (H01M50/216 takes precedence) - H01M 50/24: adapted for protecting batteries from their environment, e.g. from corrosion (thermal insulation H01M10/658) - H01M 50/293: characterised by the material - 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 - 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 In an aspect, an intumescent battery pad for a lithium ion battery comprises a polyurethane foam having a compression force deflection of 5 to 1,035 kilopascals at 25% deflection determined in accordance with ASTM D3574-17; and an intumescent material comprising an acid source, a carbon source, and a blowing agent; wherein the intumescent battery pad has a UL-V0 rating at a thickness of 1 millimeter. In another aspect, a battery can comprise at least two battery cells; and an intumescent battery pad located in between the at least two battery cells. ## Claims ### Claim 1 An intumescent battery pad for a lithium ion battery, comprising: a polyurethane foam having a compression force deflection of 5 to 1,035 kilopascal at 25% deflection determined in accordance with ASTM D3574-17; and an intumescent material comprising an acid source, a carbon source, and a blowing agent; wherein the intumescent battery pad has a UL-V0 rating at a thickness of 1 millimeter, and wherein the intumescent material is present as a coating layer having a thickness of 25 to 250 micrometers on at least an exterior surface of the foam. ### Claim 2 (depends on 1) The intumescent battery pad of claim 1, wherein the intumescent battery pad has a thickness of 1 to 5 millimeters. ### Claim 3 (depends on 1) The intumescent battery pad of claim 1, wherein the polyurethane foam has at least one of the compression force deflection of 5 to 500 kPa at 25% deflection determined in accordance with ASTM D3574-17; a compression force deflection of 100 to 500 kPa at 75% deflection determined in accordance with ASTM D3574-17; a compression set at 50% deflection of 0 to 15% as determined in accordance with ASTM D3574-95, Test D at 23° C. or 70° C.; or a SAG factor as defined by the compression force deflection at 65% divided by the compression force deflection at 25% of less than or equal to 3. ### Claim 4 (depends on 1) The intumescent battery pad of claim 1, wherein the acid source comprises at least one of an organic or inorganic phosphorous or a sulfate; wherein the organic or inorganic phosphorous compound comprises at least one of tris(2,3-dibromopropyl)phosphate, tris(2-chloroethyl)phosphate, tris(2,3-dichloropropyl)phosphate, tris(1-chloro-3-bromoisopropyl) phosphate, bis(1-chloro-3-bromoisopropyl)-1-chloro-3-bromoisopropyl phosphonate, polyaminotriazine phosphate, melamine phosphate, or guanylurea phosphate; an organophosphite ester; or a phosphorus-containing inorganic compound. ### Claim 5 (depends on 1) The intumescent battery pad of claim 1, wherein the carbon source comprises at least one of dextrin, a phenol-formaldehyde resin, pentaerythritol, a clay, or a polymer. ### Claim 6 (depends on 1) The intumescent battery pad of claim 1, wherein the blowing agent comprises at least one of a dicyandiamide, an azodicarbonamide, a melamine, a guanidine, a glycine, a urea, or a halogenated organic material. ### Claim 7 (depends on 1) The intumescent battery pad of claim 1, wherein the blowing agent decomposes at a temperature of greater than or equal to 120° C. ### Claim 8 (depends on 1) The intumescent battery pad of claim 1, wherein the intumescent material further comprises at least one of a synergist or a binder. ### Claim 9 (depends on 1) The intumescent battery pad of claim 1, wherein the intumescent material is located on all of the surfaces of the intumescent battery pad. ### Claim 10 (depends on 1) The intumescent battery pad of claim 1, wherein the polyurethane foam has the compression force deflection of 5 to 500 kPa at 25% deflection determined in accordance with ASTM D3574-17; a compression force deflection of 100 to 500 kPa at 75% deflection determined in accordance with ASTM D3574-17; a compression set at 50% deflection of 0 to 15% as determined in accordance with ASTM D3574-95, Test D at 23° C. or 70° C.; and a SAG factor as defined by the compression force deflection at 65% divided by the compression force deflection at 25% of less than or equal to 3. ### Claim 11 (depends on 1) A method of making the intumescent battery pad of claim 1, comprising: coating a frothed composition comprising a reactive mixture onto a release liner; curing the reactive mixture to form the polyurethane foam; and wherein the frothed composition comprises the intumescent material, or wherein the method further comprises depositing the intumescent material on at least one surface of the polyurethane foam to form the intumescent battery pad. ### Claim 12 (depends on 11) The method of claim 11, wherein the coating the frothed composition comprises depositing the frothed composition on the release liner at a deposition location; and wherein the curing the reactive mixture comprises translating frothed composition and the release liner through a heating zone to cure the reactive mixture and form the polyurethane foam. ### Claim 13 (depends on 12) The method of claim 12, wherein the depositing the intumescent material comprises translating the polyurethane foam from the heating zone to an intumescent material deposition zone and depositing the intumescent material on the polyurethane foam. ### Claim 14 (depends on 12) The method of claim 12, wherein the depositing the intumescent material comprises translating the polyurethane foam from the heating zone to an intumescent material dipping zone to provide the intumescent material on the polyurethane foam. ### Claim 15 (depends on 12) The method of claim 12, wherein the frothed composition comprises the intumescent material. ### Claim 16 (depends on 1) A method of making the intumescent battery pad of claim 1, comprising depositing the intumescent material on the polyurethane foam. ### Claim 17 (depends on 16) The method of claim 16, wherein the depositing comprises dip coating, flow coating, or spray coating. ### Claim 18 A battery comprising: at least two battery cells; and an intumescent battery pad located in between the at least two battery cells; wherein the intumescent battery pad comprises a polyurethane foam and an intumescent material; wherein the polyurethane foam has a compression force deflection of 5 to 1,035 kilopascal at 25% deflection determined in accordance with ASTM D3574-17; and wherein the intumescent material comprises an acid source, a carbon source, and a blowing agent; wherein the intumescent battery pad has a UL-V0 rating at a thickness of 1 millimeter, and wherein the intumescent material is present as a coating layer having a thickness of 25 to 250 micrometers on at least an exterior surface of the foam. ### Claim 19 (depends on 18) The battery of claim 18, wherein the battery is a lithium ion battery for a vehicle. ### Claim 20 (depends on 18) The battery of claim 18, wherein the polyurethane foam has the compression force deflection of 5 to 500 kPa at 25% deflection determined in accordance with ASTM D3574-17; a compression force deflection of 100 to 500 kPa at 75% deflection determined in accordance with ASTM D3574-17; a compression set at 50% deflection of 0 to 15% as determined in accordance with ASTM D3574-95, Test D at 23° C. or 70° C.; and a SAG factor as defined by the compression force deflection at 65% divided by the compression force deflection at 25% of less than or equal to 3.