# US 2022/0285752 A1 · Battery cooling device with fire protection material, battery module with fire protection material, and aircraft > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0285752 A1 - Document ID: US20220285752A1 - Status: Published application - Kind: A1 - Application number: 17/687,763 - Filed: 2022-03-07 - Published: 2022-09-08 - Earliest claimed: 2021-03-05 - Assignees: Volocopter GmbH - Applicants: Volocopter GmbH - Inventors: Nils ZIEGLER - Web page: https://patentgrep.com/patent/US20220285752A1 ## CPC - H01M 10/613: Cooling or keeping cold - H01M 10/6568: characterised by flow circuits, e.g. loops, located externally to the cells or cell casings - H01M 10/625: Vehicles - 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 50/143: Fireproof; Explosion-proof - H01M 50/202: Casings or frames around the primary casing of a single cell or a single battery - H01M 50/222: Inorganic material - H01M 50/227: Organic material - H01M 50/231: having a layered structure - H01M 50/249: specially adapted for aircraft or vehicles, e.g. cars or trains (constructional details of batteries specially adapted for electric vehicles B60L50/64) - H01M 10/643: Cylindrical cells - H01M 10/653: characterised by electrically insulating or thermally conductive materials - H01M 2220/20: Batteries in motive systems, e.g. vehicle, ship, plane - 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 battery cooling device for cooling at least one battery cell (1) of an electrically driven aircraft is provided, with a latent heat store (3). The battery cell is surrounded by a multilayer system having at least two layers (2,4) of fire protection material and a layer of the phase change material of the latent heat store, where an inner layer of the multilayer system, facing the battery cell, and an outer layer of the multilayer system, facing the surroundings, are formed of the fire protection material, and a middle layer, which is disposed between the inner and the outer layers, is formed of the phase change material of the latent heat store, and the fire protection material is of at least two-layer form, where a first layer of the fire protection material is mechanically stable in form and a second layer of the fire protection material comprises hydrated material. ## Claims ### Claim 1 A battery cooling device for cooling at least one battery cell (1) of an electrically driven aircraft, the battery cooling device comprising: a latent heat store (3), a multilayer system surrounding the at least one battery cell, said multilayer system comprising at least two layers (2, 4) of fire protection material and a layer of a phase change material that forms the latent heat store (3), the at least two layers of the multilayer system include an inner layer (2) facing the at least one battery cell (1), and an outer layer (4) facing surroundings, the inner and outer layers are formed of the fire protection material, and a middle layer (3), which is disposed between the inner layer (2) and the outer (4) layer, is formed by the layer of the phase change material of the latent heat store (3), and the fire protection material (3) comprises at least two layers, in which a first layer (2.1, 4.1) of the fire protection material is mechanically stable in form and a second layer of the fire protection material (2.2, 4.2) comprises hydrated material. ### Claim 2 (depends on 1) The battery cooling device as claimed in claim 1, wherein the first layer of the fire protection material (2.1) of the inner layer (2) is disposed directly on the at least one battery cell (1). ### Claim 3 (depends on 1) The battery cooling device as claimed in claim 1, wherein the phase change material of the latent heat store (3) is macroencapsulated in a carrier matrix. ### Claim 4 (depends on 1) The battery cooling apparatus as claimed in claim 1, wherein the phase change material of the latent heat store (3) is formed as a slit sleeve around the inner layer (2) of fire protection material. ### Claim 5 (depends on 1) The battery cooling apparatus as claimed in claim 1, wherein the phase change material of the latent heat store (3) is configured for a temperature range for an evolution of heat by the at least one battery cell (1) in an operating state. ### Claim 6 (depends on 5) The battery cooling device of claim 5, wherein the temperature range is from 20° C. to 150° C. ### Claim 7 (depends on 1) The battery cooling device as claimed in claim 1, wherein the first layer (2.1, 4.1) of the fire protection material (2, 4) is formed with fiber material. ### Claim 8 (depends on 7) The battery cooling device as claimed in claim 7, wherein the fiber material comprises at least one of glass fibers, ceramic fibers, or aramid fibers ### Claim 9 (depends on 1) The battery cooling device as claimed in claim 1, wherein the second layer of the fire protection material (2.2, 4.2) is formed with hydrated minerals. ### Claim 10 (depends on 9) The battery cooling device as claimed in claim 9, wherein the hydrated minerals comprise at least one metal hydrate. ### Claim 11 (depends on 1) The battery cooling device as claimed in claim 1, wherein the second layer of the fire protection material (2.2, 4.2) is configured for a temperature range for an evolution of heat by the battery cell on thermal runaway of the battery cell. ### Claim 12 (depends on 11) The battery cooling device as claimed in claim 11, wherein the temperature range is from 100° to 800°. ### Claim 13 (depends on 1) The battery cooling device as claimed in claim 1, wherein at least one of the inner (2) or the outer (4) layers of fire protection material are self-adhesive. ### Claim 14 (depends on 13) The battery cooling device as claimed in claim 13, wherein the first, mechanically stable layer (2.1, 4.1) of the fire protection material is self-adhesive. ### Claim 15 (depends on 1) The battery cooling device as claimed in claim 1, wherein the outer layer (4) of fire protection material completely envelops the phase change material of the latent heat store (3). ### Claim 16 (depends on 1) The battery cooling device as claimed in claim 1, wherein the inner (2) and the outer (4) layers of the fire protection material (2.2) are formed as a sleeve, and the sleeve of the outer layer of the fire protection material (4.2) overlaps the phase change material of the latent heat store (3) on both sides at the openings in the sleeve and is formed sealingly with the inner layer (2.2) of the fire protection material. ### Claim 17 (depends on 1) A battery module comprising the battery cooling device of claim 1 and a plurality of battery cells (1). ### Claim 18 (depends on 17) An aircraft comprising a battery module as claimed in claim 17. ### Claim 19 (depends on 18) The aircraft as claimed in claim 18, wherein the aircraft comprises an electrically driven, vertical take-off and landing aircraft.