EP4630508A1 - Flame-resistant, coated fabric insulator - Google Patents

Flame-resistant, coated fabric insulator

Info

Publication number
EP4630508A1
EP4630508A1 EP24712356.5A EP24712356A EP4630508A1 EP 4630508 A1 EP4630508 A1 EP 4630508A1 EP 24712356 A EP24712356 A EP 24712356A EP 4630508 A1 EP4630508 A1 EP 4630508A1
Authority
EP
European Patent Office
Prior art keywords
thermal insulator
flexible thermal
fabric layer
flame
outer coating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP24712356.5A
Other languages
German (de)
French (fr)
Inventor
Jordan Zachary BOATWRIGHT
Kamel FENNELL
Scott Mcfarland
Zobar HASSAN
Gene Jung
Hicham ROKNI
Shannon NOTARO
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Systems Protection Group US LLC
Original Assignee
Federal Mogul Powertrain LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US18/431,754 external-priority patent/US20240266632A1/en
Application filed by Federal Mogul Powertrain LLC filed Critical Federal Mogul Powertrain LLC
Publication of EP4630508A1 publication Critical patent/EP4630508A1/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J7/00—Adhesives in the form of films or foils
    • C09J7/20—Adhesives in the form of films or foils characterised by their carriers
    • C09J7/29—Laminated material
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/218—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by the material
    • H01M50/22—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by the material of the casings or racks
    • H01M50/231—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by the material of the casings or racks having a layered structure
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M50/00—Constructional details or processes of manufacture of the non-active parts of electrochemical cells other than fuel cells, e.g. hybrid cells
    • H01M50/20—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders
    • H01M50/233—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by physical properties of casings or racks, e.g. dimensions
    • H01M50/24—Mountings; Secondary casings or frames; Racks, modules or packs; Suspension devices; Shock absorbers; Transport or carrying devices; Holders characterised by physical properties of casings or racks, e.g. dimensions adapted for protecting batteries from their environment, e.g. from corrosion
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/01—Use of inorganic substances as compounding ingredients characterized by their specific function
    • C08K3/016—Flame-proofing or flame-retarding additives
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K3/00—Use of inorganic substances as compounding ingredients
    • C08K3/34—Silicon-containing compounds
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J2203/00—Applications of adhesives in processes or use of adhesives in the form of films or foils
    • C09J2203/33—Applications of adhesives in processes or use of adhesives in the form of films or foils for batteries or fuel cells
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J2301/00—Additional features of adhesives in the form of films or foils
    • C09J2301/10—Additional features of adhesives in the form of films or foils characterized by the structural features of the adhesive tape or sheet
    • C09J2301/12—Additional features of adhesives in the form of films or foils characterized by the structural features of the adhesive tape or sheet by the arrangement of layers
    • C09J2301/122—Additional features of adhesives in the form of films or foils characterized by the structural features of the adhesive tape or sheet by the arrangement of layers the adhesive layer being present only on one side of the carrier, e.g. single-sided adhesive tape
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J2301/00—Additional features of adhesives in the form of films or foils
    • C09J2301/30—Additional features of adhesives in the form of films or foils characterized by the chemical, physicochemical or physical properties of the adhesive or the carrier
    • C09J2301/302—Additional features of adhesives in the form of films or foils characterized by the chemical, physicochemical or physical properties of the adhesive or the carrier the adhesive being pressure-sensitive, i.e. tacky at temperatures inferior to 30°C
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J2301/00—Additional features of adhesives in the form of films or foils
    • C09J2301/40—Additional features of adhesives in the form of films or foils characterized by the presence of essential components
    • C09J2301/41—Additional features of adhesives in the form of films or foils characterized by the presence of essential components additives as essential feature of the carrier layer
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J2400/00—Presence of inorganic and organic materials
    • C09J2400/10—Presence of inorganic materials
    • C09J2400/14—Glass
    • C09J2400/143—Glass in the substrate
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J2400/00—Presence of inorganic and organic materials
    • C09J2400/20—Presence of organic materials
    • C09J2400/26—Presence of textile or fabric
    • C09J2400/263—Presence of textile or fabric in the substrate
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J2433/00—Presence of (meth)acrylic polymer
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
    • C09J2483/00—Presence of polysiloxane
    • C09J2483/006—Presence of polysiloxane in the substrate
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Definitions

  • This invention relates generally to thermal insulators, and more particularly to thermal insulators for inhibiting flame propagation between and from cells of a battery pack of an electric vehicle.
  • the fiberglass insulator can result in a thermal runaway condition originating in any one of the cells 16 of the battery’ pack 12, such that flame propagates from a single cell 16 (Figure 2A) to multiple cells (Figure 2C), in less than 10 minutes at a temperature of 1000 °C. [0004] It is desired to provide a thermal insulation that inhibits the propagation of flame between cells of a battery pack when exposed to a flame at a distance of about 25mm for 10 minutes or more at a temperature of 1200 °C - 1400 °C.
  • the insulator material is provided as a coated fabric insulator having a fabric layer, a flame resistant outer coating bonded to an outer side of the fabric layer, and a pressure-sensitive adhesive layer bonded to an inner side of the fabric layer, wherein the fabric layer is sandwiched between the flame-resistant outer coating and the pressure-sensitive adhesive layer.
  • the fabric layer can be provided as a fabric woven with mineral yams.
  • the mineral yams of the woven fabric can be provided from at least one of silica multifilaments, fiberglass multifilaments, basalt multifilaments, and nomex multifilaments.
  • the woven fabric is provided having a fabric weight of about 30 - 40oz/sq-yd.
  • a release layer is releasably bonded to the pressure-sensitive adhesive layer for removal to expose the pressure-sensitive adhesive layer for adhesion to a surface of the electric vehicle battery' pack.
  • the pressure-sensitive adhesive is fire-resistant.
  • the pressure-sensitive adhesive is an acry lic adhesive.
  • the flame resistant outer coating is provided as a compound including a liquid silicone rubber (LSR) infused with a fire-resistant material.
  • LSR liquid silicone rubber
  • the compound includes between about 5% by mass to 30% by mass of the fire-resistant material.
  • the fire-resistant material infused in the LSR is powdered mica.
  • the compound has about 15% powered mica by mass.
  • the flame resistant outer coating is cured.
  • the flame resistant outer coating has a thickness between about 0.5 to 1.0mm.
  • the coated fabric insulator has a thickness between about 1.0 to 2.0mm. [0022] In accordance with another aspect of the invention, the coated fabric insulator has a maximum thickness of 2.0mm.
  • an electric vehicle battery pack includes a housing bounding a plurality' of cells. Further, a coated fabric insulator is disposed between and/or about the plurality' of cells.
  • the coated fabric insulator includes a fabric layer, aflame resistant outer coating bonded to an outer side of the fabric layer, and a pressure-sensitive adhesive layer bonded to an inner side of the fabric layer, yvherein the fabric layer is sandwiched between the flame-resistant outer coating and the pressure-sensitive adhesive layer.
  • a method of constructing an insulator material for use yvith an electric vehicle battery pack includes interlacing mineral yam to form a fabric layer. Further, forming a compound by mixing a liquid silicone rubber (LSR) with a fire-resistant material, bonding the compound to an outer side of the fabric layer and curing the compound to form a flame-resistant outer coating. Further, bonding an adhesive to an inner side of the fabric layer, and protecting the adhesive with a release layer.
  • LSR liquid silicone rubber
  • the method can further include infusing the compound on the fabric layer such that the compound fills interstices between the interlaced mineral yams.
  • the method can further include providing the fire-resistant material in the compound as powdered mica.
  • the method further includes providing the powdered mica having a mass between about 5 to 30% of the compound.
  • the method can further include providing the powdered mica having a mass between about 15% of the compound. [0029] In accordance with another aspect of the invention, the method further includes providing the flame-resistant outer coating having a thickness between about 0.5 mm to 1.0mm. [0030] In accordance with another aspect of the invention, the method further includes providing the insulator material having a maximum thickness of 2.0mm.
  • the method can further include providing the pressure-sensitive adhesive as an acry lic adhesive.
  • the method further includes providing the pressure-sensitive adhesive having a peal strength of about 5N/25mm under normal operating conditions.
  • the method further includes providing the fabric layer having a fabric weight between about 30 oz/sq-yd to 40 oz/sq-yd.
  • the method can further include forming the fabric layer in a weaving process.
  • the method can further include forming the fabric layer with at least one of silica multifilaments, fiberglass multi fi laments, basalt multi filaments, and nomex multifilaments.
  • the method can further include forming the fabric layer entirely with silica multifilaments.
  • Figure 1 is a schematic perspective view of an electric motor vehicle having a battery pack with a multilayer thermal insulator constructed in accordance with an aspect of the invention
  • Figures 2A-2C illustrate a schematic representation of an electric vehicle battery pack in accordance with prior art, without a coated fabric insulator in accordance with the disclosure, undergoing a thermal runaway condition with a flame propagating without hindrance from a location of flame initiation (Figure 2A) throughout a plurality of cells of the battery 7 pack ( Figure 2C);
  • Figures 3A-3C are views similar to Figures 2A-2C, with the electric vehicle battery' pack including a coated fabric insulator constructed in accordance with an aspect of the disclosure, with the coated fabric insulator shown suppressing and inhibiting flame propagating from a location of a thermal runaway condition within a single cell (Figure 3A) throughout the plurality of cells of the battery pack ( Figure 3C);
  • Figure 4 is a schematic side view of a flexible thermal insulator in accordance with a non-limiting embodiment of the disclosure.
  • Figure 5 is a partially broken away, fragmentary perspective view of the flexible thermal insulator in accordance of FIG. 4.
  • FIG. 1 illustrates a motor vehicle, shown as an electrically powered motor vehicle, also referred to as electric vehicle EV, having a battery pack 12, such as a lithium-ion battery pack, by way of example and w ithout limitation, configured with an insulator material, also referred to as coated fabric insulator or flexible thermal insulator 10, in accordance with an aspect of the invention.
  • the electric vehicle battery pack 12 includes a housing member, also referred to as casing or housing 14, bounding a plurality of cells 16, and including bus-bars interconnecting cells, high voltage electrical connectors, cell interfaces, low voltage signal wires, high voltage cables and a cooling system having cooling tubes through which coolant can flow, as is generally known in electric vehicle battery packs.
  • a thermal runaway condition originating in any one of the cells 16 of a battery pack 12, with the multilayer thermal insulator 10 being disposed between and/or about the cells 16, is controlled and contained via the multilayer thermal insulator 10, as illustrated in Figures 3A-3C, such that flame propagation is prevented for at least 10 minutes at an internal cell temperature ranging between 1200 - 1400 °C, and an outer surface temperature of the battery housing 14, also referred to as case, is maintained to be less than 400 °C, and preferably 370 °C, for at least 10 minutes.
  • the flexible thermal insulator 10 can withstand 2000 V dielectric conditions prior to and after exposure to flame for 10 minutes, and has a tensile strength of no less than 200 N/
  • the thermal insulator(s) 10 which can be arranged between adjacent cells 16 to thermally isolate the cells 16 from one another, as well as to shield and protect surfaces of the battery pack housing 14, the aforementioned bus-bars, high voltage electrical connectors, cell interfaces, low voltage signal wires, high voltage cables and cooling tubes against extreme temperature thermal runaway conditions and contamination, such as from fluid or debris, as well as from impact forces, such as may be experienced in a crash condition, is provided as a relatively thin, flexible composite wall 18, such as being no greater than 2.0mm in thickness.
  • the wall 18, being thin and flexible, can be configured as needed, such as by being able to be wrapped into a hollow tubular sleeve configuration about bus bars, wires, tubes, connectors and the like, and can also be used in sheet form, such as a flat planar sheet, to provide a protective outer barrier about an outer periphery of the cells 16. as well as to provide a protective barrier between adjacent cells 16 to effectively thermally isolate each cell 16 from an adjacent cell 16.
  • the composite wall 18, as shown schematically in Figure 4 and photographically in Figure 5, includes a fabric layer 20, a flame resistant outer coating 22 bonded to an outer surface, also referred to as outer side 24, of the fabric layer 20, and a pressure-sensitive adhesive layer 26 bonded to an inner surface, also referred to as inner side 28, of the fabric layer 20.
  • the fabric layer 20 is sandwiched between the flame- resistant outer coating 22 and the pressure-sensitive adhesive layer 26.
  • the fabric layer 20 is provided as a textile layer, such as via a fabric woven with mineral yams 30.
  • the fabric is woven having a tight weave pattern to enhance flameresistance, such as via a plain weave pattern, by way of example and without limitation, and having a fabric weight between about 30 oz/sq-yd to 40 oz/sq-yd.
  • the mineral yams 30 of the woven fabric 20 can be provided from at least one of silica multifilaments, fiberglass multifilaments, basalt multifilaments, and nomex multifilaments, by way of example and without limitation.
  • the pressure-sensitive adhesive layer 26 is fire-resistant, and in one preferred embodiment, is provided as an acrylic adhesive.
  • a release layer 32 is releasably bonded to a side of the pressure-sensitive adhesive layer 26 facing away from the fabric layer 20 for selective removal to expose the underlying pressure-sensitive adhesive layer 26 for adhesion to a desired surface of the electric vehicle battery pack 12.
  • the pressure-sensitive adhesive layer 26 provides a minimum peal strength of 5 N/25mm under normal operating conditions.
  • the flame-resistant outer coating 22, shown broken away in Figure 5 solely for illustration of the underlying fabric layer 20. is provided as a compound including a liquid silicone rubber (LSR) infused with a fire-resistant material.
  • the fire-resistant material infused into the LSR is powdered mica.
  • the flameresistant outer coating 22 includes between about 5 to 30% by mass of the fire-resistant material.
  • the flame-resistant outer coating 22 has between about 10 to 20% by mass of powdered mica, and more particularly, about 15% powered mica by mass.
  • the flame resistant outer coating 22 is cured after being bonded to the fabric layer 20.
  • the flame resistant outer coating 22 has a thickness between about 0.5 to 1.0mm.
  • the flame-resistant outer coating 22 can be bonded in flush or overlying relation with an outer periphery of the fabric layer 20, thereby enhancing flame-resistance, as well as resistance to fabric end fray, such that no filaments of the fabric layer 20 extend more than 5mm beyond an outer periphery of the flexible thermal insulator 10.
  • an electric vehicle battery pack 12 is provided.
  • the electric vehicle battery' pack 12 includes a housing 14 bounding a plurality of cells 16.
  • a coated fabric insulator 10 is disposed between and/or about the plurality of cells 16.
  • the coated fabric insulator 10 includes a fabric layer 20, aflame resistant outer coating 22 bonded to an outer side 24 of the fabric layer 20, and a pressure-sensitive adhesive layer 26 bonded to an inner side 28 of the fabric layer 20, such that the fabric layer 20 is sandwiched between the flame-resistant outer coating 22 and the pressure-sensitive adhesive layer 26.
  • the flame-resistant outer coating 22 is provided as a compound including between about 5 to 30% by mass powdered mica.
  • the powdered mica is infused in the base material of the compound, such as liquid silicone rubber (LSR).
  • a method of constructing an insulator material 10 for use with an electric vehicle battery pack 12 includes interlacing mineral yam 30 to form a fabric layer 20. Further, forming a compound by mixing a liquid silicone rubber (LSR) with a fire-resistant material, bonding the compound to an outer surface, also referred to as outer side 24, of the fabric layer 20 and curing the compound to form a flame-resistant outer coating 22. Further, bonding an adhesive 26 to an inner surface, also referred to as inner side 28, of the fabric layer 20, and protecting the adhesive 26 with a release layer 32, until desired to expose the adhesive for adhesion to a desired surface via removal of the release layer 32.
  • LSR liquid silicone rubber
  • the method can further include infusing the compound on the fabric layer 20 such that the compound fills interstices between the interlaced mineral yams 30.
  • the method further includes providing the fire-resistant material in the compound as powdered mica having a mass between about 5 to 30% of the mass of the compound.
  • the method can further include providing the powdered mica having a mass of about 15% of the mass of the compound.
  • the method further includes providing the flame-resistant outer coating having a thickness between about 0.5 to 1.0mm.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Battery Mounting, Suspending (AREA)
  • Secondary Cells (AREA)
  • Insulating Bodies (AREA)

Abstract

A flexible thermal insulator having a fabric layer, a flame resistant outer coating bonded to an outer side of the fabric layer, and a pressure-sensitive adhesive layer bonded to an inner side of the fabric layer.

Description

FLAME-RESISTANT, COATED FABRIC INSULATOR
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63/443.227, filed February 3. 2023, and priority to U.S. Application Serial No. 18/431.754 filed February 2. 2024. which are incorporated herein by reference in their entirety.
BACKGROUND OF THE INVENTION
1. Technical Field
[0002] This invention relates generally to thermal insulators, and more particularly to thermal insulators for inhibiting flame propagation between and from cells of a battery pack of an electric vehicle.
2. Related Art
[0003] It is known to contain or shield battery’ packs, including those used in electric vehicle applications, in thermal insulation. A common material used to form such thermal insulation is a fiberglass fabric. Although the fiberglass fabric insulation provides an acceptable level of protection against contamination and environmental temperatures during normal use, the fiberglass fabric insulation does not provide a desired level of protection against flame propagation, such as may be experienced in a thermal runaway condition of one or more cells of the electric vehicle battery' pack. As shown in Figures 2A-2C. a battery pack 12 and housing 14 thereof are shown having a fiberglass insulator between and about cells 16 of the battery pack 12. The fiberglass insulator can result in a thermal runaway condition originating in any one of the cells 16 of the battery’ pack 12, such that flame propagates from a single cell 16 (Figure 2A) to multiple cells (Figure 2C), in less than 10 minutes at a temperature of 1000 °C. [0004] It is desired to provide a thermal insulation that inhibits the propagation of flame between cells of a battery pack when exposed to a flame at a distance of about 25mm for 10 minutes or more at a temperature of 1200 °C - 1400 °C.
SUMMARY OF THE INVENTION
[0005] It is an obj ect of the present disclosure to provide an insulator material for use with an electric vehicle battery' pack that addresses at least the desire to inhibit the propagation of flame from and within the battery' pack for 10 minutes or more at a temperature of 1200 - 1400 °C.
[0006] It is a further object of the present disclosure to provide an insulator material for use with an electric vehicle battery' pack that is flexible, lightweight, has a thin profde to minimize the amount of space occupied by the insulator material between cells of the battery pack and about cells of the battery' pack.
[0007] It is a further obj ect of the present disclosure to provide an insulator material for use with an electric vehicle battery pack that is economical in manufacture and in use.
[0008] In accordance with one aspect of the invention, the insulator material is provided as a coated fabric insulator having a fabric layer, a flame resistant outer coating bonded to an outer side of the fabric layer, and a pressure-sensitive adhesive layer bonded to an inner side of the fabric layer, wherein the fabric layer is sandwiched between the flame-resistant outer coating and the pressure-sensitive adhesive layer.
[0009] In accordance with another aspect of the invention, the fabric layer can be provided as a fabric woven with mineral yams.
[0010] In accordance with another aspect of the invention, the mineral yams of the woven fabric can be provided from at least one of silica multifilaments, fiberglass multifilaments, basalt multifilaments, and nomex multifilaments. [0011] In accordance with another aspect of the invention, the woven fabric is provided having a fabric weight of about 30 - 40oz/sq-yd.
[0012] In accordance with another aspect of the invention, a release layer is releasably bonded to the pressure-sensitive adhesive layer for removal to expose the pressure-sensitive adhesive layer for adhesion to a surface of the electric vehicle battery' pack.
[0013] In accordance with another aspect of the invention, the pressure-sensitive adhesive is fire-resistant.
[0014] In accordance with another aspect of the invention, the pressure-sensitive adhesive is an acry lic adhesive.
[0015] In accordance with another aspect of the invention, the flame resistant outer coating is provided as a compound including a liquid silicone rubber (LSR) infused with a fire- resistant material.
[0016] In accordance with another aspect of the invention, the compound includes between about 5% by mass to 30% by mass of the fire-resistant material.
[0017] In accordance with another aspect of the invention, the fire-resistant material infused in the LSR is powdered mica.
[0018] In accordance with another aspect of the invention, the compound has about 15% powered mica by mass.
[0019] In accordance with another aspect of the invention, the flame resistant outer coating is cured.
[0020] In accordance with another aspect of the invention, the flame resistant outer coating has a thickness between about 0.5 to 1.0mm.
[0021] In accordance with another aspect of the invention, the coated fabric insulator has a thickness between about 1.0 to 2.0mm. [0022] In accordance with another aspect of the invention, the coated fabric insulator has a maximum thickness of 2.0mm.
[0023] In accordance with another aspect of the invention, an electric vehicle battery pack is provided. The electric vehicle battery pack includes a housing bounding a plurality' of cells. Further, a coated fabric insulator is disposed between and/or about the plurality' of cells. The coated fabric insulator includes a fabric layer, aflame resistant outer coating bonded to an outer side of the fabric layer, and a pressure-sensitive adhesive layer bonded to an inner side of the fabric layer, yvherein the fabric layer is sandwiched between the flame-resistant outer coating and the pressure-sensitive adhesive layer.
[0024] In accordance yvith another aspect of the invention, a method of constructing an insulator material for use yvith an electric vehicle battery pack is provided. The method includes interlacing mineral yam to form a fabric layer. Further, forming a compound by mixing a liquid silicone rubber (LSR) with a fire-resistant material, bonding the compound to an outer side of the fabric layer and curing the compound to form a flame-resistant outer coating. Further, bonding an adhesive to an inner side of the fabric layer, and protecting the adhesive with a release layer.
[0025] In accordance with another aspect of the invention, the method can further include infusing the compound on the fabric layer such that the compound fills interstices between the interlaced mineral yams.
[0026] In accordance with another aspect of the invention, the method can further include providing the fire-resistant material in the compound as powdered mica.
[0027] In accordance with another aspect of the invention, the method further includes providing the powdered mica having a mass between about 5 to 30% of the compound.
[0028] In accordance with another aspect of the invention, the method can further include providing the powdered mica having a mass between about 15% of the compound. [0029] In accordance with another aspect of the invention, the method further includes providing the flame-resistant outer coating having a thickness between about 0.5 mm to 1.0mm. [0030] In accordance with another aspect of the invention, the method further includes providing the insulator material having a maximum thickness of 2.0mm.
[0031] In accordance with another aspect of the invention, the method can further include providing the pressure-sensitive adhesive as an acry lic adhesive.
[0032] In accordance with another aspect of the invention, the method further includes providing the pressure-sensitive adhesive having a peal strength of about 5N/25mm under normal operating conditions.
[0033] In accordance with another aspect of the invention, the method further includes providing the fabric layer having a fabric weight between about 30 oz/sq-yd to 40 oz/sq-yd.
[0034] In accordance with another aspect of the invention, the method can further include forming the fabric layer in a weaving process.
[0035] In accordance with another aspect of the invention, the method can further include forming the fabric layer with at least one of silica multifilaments, fiberglass multi fi laments, basalt multi filaments, and nomex multifilaments.
[0036] In accordance with another aspect of the invention, the method can further include forming the fabric layer entirely with silica multifilaments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0037] These and other aspects, features and advantages will become readily apparent to those skilled in the art in view of the following detailed description of presently preferred embodiments and best mode, appended claims, and accompanying drawings, in which:
[0038] Figure 1 is a schematic perspective view of an electric motor vehicle having a battery pack with a multilayer thermal insulator constructed in accordance with an aspect of the invention; [0039] Figures 2A-2C illustrate a schematic representation of an electric vehicle battery pack in accordance with prior art, without a coated fabric insulator in accordance with the disclosure, undergoing a thermal runaway condition with a flame propagating without hindrance from a location of flame initiation (Figure 2A) throughout a plurality of cells of the battery7 pack (Figure 2C);
[0040] Figures 3A-3C are views similar to Figures 2A-2C, with the electric vehicle battery' pack including a coated fabric insulator constructed in accordance with an aspect of the disclosure, with the coated fabric insulator shown suppressing and inhibiting flame propagating from a location of a thermal runaway condition within a single cell (Figure 3A) throughout the plurality of cells of the battery pack (Figure 3C);
[0041] Figure 4 is a schematic side view of a flexible thermal insulator in accordance with a non-limiting embodiment of the disclosure; and
[0042] Figure 5 is a partially broken away, fragmentary perspective view of the flexible thermal insulator in accordance of FIG. 4.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0043] Referring in more detail to the drawings, Figure 1 illustrates a motor vehicle, shown as an electrically powered motor vehicle, also referred to as electric vehicle EV, having a battery pack 12, such as a lithium-ion battery pack, by way of example and w ithout limitation, configured with an insulator material, also referred to as coated fabric insulator or flexible thermal insulator 10, in accordance with an aspect of the invention. The electric vehicle battery pack 12 includes a housing member, also referred to as casing or housing 14, bounding a plurality of cells 16, and including bus-bars interconnecting cells, high voltage electrical connectors, cell interfaces, low voltage signal wires, high voltage cables and a cooling system having cooling tubes through which coolant can flow, as is generally known in electric vehicle battery packs. During normal use. and including in non-normal situations, such as in a vehicle crash condition or some other condition causing an impact force to battery pack 12, in contrast to a battery pack 12 not having a multilayer thermal insulator 10 as disclosed herein, whereat flame propagation can result, as shown in Figures 2A-2C, a thermal runaway condition originating in any one of the cells 16 of a battery pack 12, with the multilayer thermal insulator 10 being disposed between and/or about the cells 16, is controlled and contained via the multilayer thermal insulator 10, as illustrated in Figures 3A-3C, such that flame propagation is prevented for at least 10 minutes at an internal cell temperature ranging between 1200 - 1400 °C, and an outer surface temperature of the battery housing 14, also referred to as case, is maintained to be less than 400 °C, and preferably 370 °C, for at least 10 minutes. The flexible thermal insulator 10 can withstand 2000 V dielectric conditions prior to and after exposure to flame for 10 minutes, and has a tensile strength of no less than 200 N/cm.
[0044] As shown schematically in Figures 3A-3C, the thermal insulator(s) 10, which can be arranged between adjacent cells 16 to thermally isolate the cells 16 from one another, as well as to shield and protect surfaces of the battery pack housing 14, the aforementioned bus-bars, high voltage electrical connectors, cell interfaces, low voltage signal wires, high voltage cables and cooling tubes against extreme temperature thermal runaway conditions and contamination, such as from fluid or debris, as well as from impact forces, such as may be experienced in a crash condition, is provided as a relatively thin, flexible composite wall 18, such as being no greater than 2.0mm in thickness. The wall 18, being thin and flexible, can be configured as needed, such as by being able to be wrapped into a hollow tubular sleeve configuration about bus bars, wires, tubes, connectors and the like, and can also be used in sheet form, such as a flat planar sheet, to provide a protective outer barrier about an outer periphery of the cells 16. as well as to provide a protective barrier between adjacent cells 16 to effectively thermally isolate each cell 16 from an adjacent cell 16. [0045] The composite wall 18, as shown schematically in Figure 4 and photographically in Figure 5, includes a fabric layer 20, a flame resistant outer coating 22 bonded to an outer surface, also referred to as outer side 24, of the fabric layer 20, and a pressure-sensitive adhesive layer 26 bonded to an inner surface, also referred to as inner side 28, of the fabric layer 20. As such, the fabric layer 20 is sandwiched between the flame- resistant outer coating 22 and the pressure-sensitive adhesive layer 26.
[0046] The fabric layer 20 is provided as a textile layer, such as via a fabric woven with mineral yams 30. The fabric is woven having a tight weave pattern to enhance flameresistance, such as via a plain weave pattern, by way of example and without limitation, and having a fabric weight between about 30 oz/sq-yd to 40 oz/sq-yd. The mineral yams 30 of the woven fabric 20 can be provided from at least one of silica multifilaments, fiberglass multifilaments, basalt multifilaments, and nomex multifilaments, by way of example and without limitation.
[0047] The pressure-sensitive adhesive layer 26 is fire-resistant, and in one preferred embodiment, is provided as an acrylic adhesive. A release layer 32 is releasably bonded to a side of the pressure-sensitive adhesive layer 26 facing away from the fabric layer 20 for selective removal to expose the underlying pressure-sensitive adhesive layer 26 for adhesion to a desired surface of the electric vehicle battery pack 12. The pressure-sensitive adhesive layer 26 provides a minimum peal strength of 5 N/25mm under normal operating conditions.
[0048] The flame-resistant outer coating 22, shown broken away in Figure 5 solely for illustration of the underlying fabric layer 20. is provided as a compound including a liquid silicone rubber (LSR) infused with a fire-resistant material. In accordance an aspect of the disclosure, the fire-resistant material infused into the LSR is powdered mica. The flameresistant outer coating 22 includes between about 5 to 30% by mass of the fire-resistant material. In accordance with one exemplary embodiment, the flame-resistant outer coating 22 has between about 10 to 20% by mass of powdered mica, and more particularly, about 15% powered mica by mass. The flame resistant outer coating 22 is cured after being bonded to the fabric layer 20. The flame resistant outer coating 22 has a thickness between about 0.5 to 1.0mm. The flame-resistant outer coating 22 can be bonded in flush or overlying relation with an outer periphery of the fabric layer 20, thereby enhancing flame-resistance, as well as resistance to fabric end fray, such that no filaments of the fabric layer 20 extend more than 5mm beyond an outer periphery of the flexible thermal insulator 10.
[0049] In accordance with another aspect of the invention, an electric vehicle battery pack 12 is provided. The electric vehicle battery' pack 12 includes a housing 14 bounding a plurality of cells 16. Further, a coated fabric insulator 10 is disposed between and/or about the plurality of cells 16. The coated fabric insulator 10 includes a fabric layer 20, aflame resistant outer coating 22 bonded to an outer side 24 of the fabric layer 20, and a pressure-sensitive adhesive layer 26 bonded to an inner side 28 of the fabric layer 20, such that the fabric layer 20 is sandwiched between the flame-resistant outer coating 22 and the pressure-sensitive adhesive layer 26. The flame-resistant outer coating 22 is provided as a compound including between about 5 to 30% by mass powdered mica. The powdered mica is infused in the base material of the compound, such as liquid silicone rubber (LSR).
[0050] In accordance with another aspect of the invention, a method of constructing an insulator material 10 for use with an electric vehicle battery pack 12 is provided. The method includes interlacing mineral yam 30 to form a fabric layer 20. Further, forming a compound by mixing a liquid silicone rubber (LSR) with a fire-resistant material, bonding the compound to an outer surface, also referred to as outer side 24, of the fabric layer 20 and curing the compound to form a flame-resistant outer coating 22. Further, bonding an adhesive 26 to an inner surface, also referred to as inner side 28, of the fabric layer 20, and protecting the adhesive 26 with a release layer 32, until desired to expose the adhesive for adhesion to a desired surface via removal of the release layer 32.
[0051] In accordance with another aspect of the invention, the method can further include infusing the compound on the fabric layer 20 such that the compound fills interstices between the interlaced mineral yams 30.
[0052] The method further includes providing the fire-resistant material in the compound as powdered mica having a mass between about 5 to 30% of the mass of the compound.
[0053] In accordance with another aspect of the invention, in one exemplary embodiment, the method can further include providing the powdered mica having a mass of about 15% of the mass of the compound.
[0054] In accordance with another aspect of the invention, the method further includes providing the flame-resistant outer coating having a thickness between about 0.5 to 1.0mm.
[0055] Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is contemplated that all features of all claims and of all embodiments can be combined with each other, so long as such combinations would not contradict one another. It is, therefore, to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

Claims

What is claimed is:
1. A flexible thermal insulator for an electric vehicle battery pack, comprising: a fabric layer; a flame resistant outer coating bonded to an outer side of the fabric layer; and a pressure-sensitive adhesive layer bonded to an inner side of the fabric layer, wherein the fabric layer is sandwiched between the flame-resistant outer coating and the pressuresensitive adhesive layer.
2. The flexible thermal insulator of claim 1, wherein the fabric layer includes woven mineral yams.
3. The flexible thermal insulator of claim 2, wherein the mineral yams include at least one of silica multifilaments, fiberglass multifilaments, basalt multifilaments, and nomex multifilaments.
4. The flexible thermal insulator of claim 2, wherein the fabric layer is woven having a fabric weight between about 30 oz/sq-yd to 40 oz/sq-yd.
5. The flexible thermal insulator of claim 1, further including a release layer releasably bonded to the pressure-sensitive adhesive layer for removal to expose the pressure-sensitive adhesive layer for adhesion to a surface of the electric vehicle battery pack.
6. The flexible thermal insulator of claim 1, wherein the pressure-sensitive adhesive is fire-resistant.
7. The flexible thermal insulator of claim 6, wherein the pressure-sensitive adhesive is an acrylic adhesive.
8. The flexible thermal insulator of any one of claim 1, wherein the flame resistant outer coating is a compound including liquid silicone rubber (LSR) infused with a fire-resistant material.
9. The flexible thermal insulator of claim 8, wherein the compound includes between about 5 to 30% by mass of the fire-resistant material.
10. The flexible thermal insulator of claim 9, wherein the fire-resistant material is pow dered mica.
11. The flexible thermal insulator of claim 10, wherein the compound includes about 15% by mass of the powdered mica.
12. The flexible thermal insulator of claim 1, wherein the flame resistant outer coating is cured.
13. The flexible thermal insulator of claim 1, wherein the flame resistant outer coating has a thickness between about 0.5mm to 1.0mm.
14. The flexible thermal insulator of claim 1, wherein the flexible thermal insulator has a thickness between about 1.0mm to 2.0mm.
15. An electric vehicle battery pack, comprising: a housing; a plurality of cells bounded by said housing; and a flexible thermal insulator fixed to at least one surface of the housing, the flexible thermal insulator having: a fabric layer; a flame resistant outer coating bonded to an outer side of the fabric layer; and a pressure-sensitive adhesive layer bonded to an inner side of the fabric layer, wherein the fabric layer is sandwiched between the flame-resistant outer coating and the pressure-sensitive adhesive layer.
16. The electric vehicle battery pack of claim 15, wherein the flame resistant outer coating is a compound including liquid silicone rubber (LSR) infused with a fire-resistant material.
17. The electric vehicle battery pack of claim 16, wherein the flame resistant outer coating is cured.
18. The electric vehicle battery pack of claim 17, wherein the fire-resistant material is powdered mica.
19. The electric vehicle battery' pack of claim 18, wherein the compound includes between about 5 to 30% by mass of the powdered mica.
20. The electric vehicle battery' pack of claim 15, wherein the fabric layer includes mineral yams woven having a fabric weight between about 30 oz/sq-yd to 40 oz/sq-yd.
EP24712356.5A 2023-02-03 2024-02-05 Flame-resistant, coated fabric insulator Pending EP4630508A1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US202363443227P 2023-02-03 2023-02-03
US18/431,754 US20240266632A1 (en) 2023-02-03 2024-02-02 Flame-resistant, coated fabric insulator
PCT/US2024/014398 WO2024163989A1 (en) 2023-02-03 2024-02-05 Flame-resistant, coated fabric insulator

Publications (1)

Publication Number Publication Date
EP4630508A1 true EP4630508A1 (en) 2025-10-15

Family

ID=90366309

Family Applications (1)

Application Number Title Priority Date Filing Date
EP24712356.5A Pending EP4630508A1 (en) 2023-02-03 2024-02-05 Flame-resistant, coated fabric insulator

Country Status (5)

Country Link
EP (1) EP4630508A1 (en)
JP (1) JP2026506545A (en)
CN (1) CN120548348A (en)
MX (1) MX2025008594A (en)
WO (1) WO2024163989A1 (en)

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20070098955A1 (en) * 2005-10-31 2007-05-03 Emanuel Magoulas Multi-layer tape for wire installation in aircraft
CN103692707A (en) * 2013-12-17 2014-04-02 3M创新有限公司 Fireproof film and electric equipment
CN104212175A (en) * 2014-08-21 2014-12-17 安徽吉安特种线缆制造有限公司 Modified mica for fire-resistant silicon rubber power cable material and preparation method of modified mica
US20230018024A1 (en) * 2021-07-19 2023-01-19 Federal-Mogul Powertrain Llc Thermal and dielectric insulator for battery pack
EP4409677A2 (en) * 2021-11-30 2024-08-07 Federal-Mogul Powertrain LLC Bus bar protective cover and method of construction thereof

Also Published As

Publication number Publication date
JP2026506545A (en) 2026-02-25
MX2025008594A (en) 2026-01-07
WO2024163989A1 (en) 2024-08-08
CN120548348A (en) 2025-08-26

Similar Documents

Publication Publication Date Title
CA1219515A (en) Intumescent fire protective sheaths
JP2023551707A (en) Multilayer protection element for batteries
ES2762491T3 (en) Fire resistant electric cable
CN118891782A (en) Fire-resistant busbar with integrated cap and battery pack containing the same
US20230018024A1 (en) Thermal and dielectric insulator for battery pack
US20240266632A1 (en) Flame-resistant, coated fabric insulator
EP4630508A1 (en) Flame-resistant, coated fabric insulator
JP7799029B2 (en) Thermal and electrical insulators for battery packs
EP4409677A2 (en) Bus bar protective cover and method of construction thereof
CN115700942A (en) Battery equipment and motor vehicles with fire protection
US20250070361A1 (en) Multilayer battery pack insulator with mechanically joined layers
WO2025043141A1 (en) Multilayer battery pack insulator with mechanically joined layers
WO2024159206A1 (en) Mechanically coupled, multilayer battery pack insulator
WO2025072662A1 (en) Multilayer battery pack insulator
US20240258603A1 (en) Mechanically coupled, multilayer battery pack insulator
EP3408853B1 (en) Fire resistive cable system
US20250112310A1 (en) Multilayer battery pack insulator
CN221775443U (en) Flexible multilayer battery pack insulators for electric vehicles
WO2025128453A1 (en) Multilayer battery pack insulator and method of construction thereof
CN221937710U (en) Flexible multilayer battery pack insulators for electric vehicles
US20250202004A1 (en) Multilayer battery pack insulator and method of construction thereof
US20240390711A1 (en) Circumferentially continuous, expandable fire suppressing, dielectric sleeve
WO2025184258A1 (en) Multilayer battery pack insulator and method of construction thereof
US20250283569A1 (en) Circumferentially continuous, fire resistant, multilayer thermal sleeve
CN223155711U (en) Ceramic environment-friendly insulating fireproof low-voltage cable

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20250710

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR