PET compounding and embossed aerogel processing

Abstract

An aerogel composite sheet material and related methods are disclosed. In one aspect, an aerogel composite sheet material includes a plurality of individual fibrous sheets arranged in a stack, and a matrix including an aerogel surrounding the plurality of individual fibrous sheets. In one aspect, an aerogel composite sheet material includes a fibrous sheet and a matrix including an aerogel surrounding the fibrous sheet. The aerogel composite sheet material can include an exposed major surface, the exposed major surface including a fracture surface.

Description

[0001] Priority claim

[0002] This patent application claims the benefit of priority under 35 U.S.C. §119(e) to U.S. Provisional Patent Application No. 63 / 453,388, filed on March 20, 2023, entitled “Composite and Embossed Aerogel Processing,” which is hereby incorporated by reference in its entirety. Technical Field

[0003] The present disclosure generally relates to composite sheets that provide thermal insulation. In one particular embodiment, materials and methods for preventing or mitigating thermal events, such as thermal runaway issues, in energy storage systems are described. Specifically, the present disclosure provides thermal barrier materials. The present disclosure also relates to battery systems or battery packs having one or more battery cells that include thermal barrier materials, and systems including such battery systems or battery packs. Background Art

[0004] Thermal barriers are used in many heat-related applications. One important application includes lithium-ion battery packs, where thermal barriers are used to provide isolation between adjacent cells and external components. Thermal barrier isolation improves safety in the event of a thermal runaway event in one or more cells of a battery module. While lithium-ion battery packs are described as one aspect of thermal barriers in this disclosure, the disclosure is not limited thereto.

[0005] Lithium-ion batteries (LIBs) are widely used to power portable electronic devices such as mobile phones, tablets, laptops, power tools, and other high-current devices such as electric vehicles due to their high operating voltage, low memory effect, and high energy density compared to traditional batteries. However, safety is an issue as LIBs are susceptible to catastrophic failure under "abuse conditions," such as when rechargeable batteries are overcharged (charged to a voltage exceeding the design voltage), over-discharged, operated at, or exposed to high temperatures and voltages.

[0006] To prevent cascading thermal runaway events, effective thermal insulation and heat dissipation strategies are needed to address these and other technological challenges of LIBs. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1A A battery system according to some aspects is shown.

[0008] Figure 1B Shows some aspects Figure 1A Cross-section of the battery pack system in Figure 1.

[0009] Figure 2 Shown is a stack of composite sheet material according to some aspects.

[0010] Figure 3 An aerogel composite sheet material according to some aspects is shown.

[0011] Figure 4 Another example of an aerogel composite sheet material according to some aspects is shown.

[0012] Figure 5A Another example of an aerogel composite sheet material according to some aspects is shown.

[0013] Figure 5B Shown is a close-up view of an aerogel composite sheet material having a fractured surface according to some aspects.

[0014] Figure 5C Shown is a close-up view of an aerogel composite sheet material having a fractured surface according to some aspects.

[0015] Figure 5D A picture showing an aerogel composite sheet material according to some aspects is shown.

[0016] Figure 6 A fiber sheet according to some aspects is shown.

[0017] Figure 7 Shown is an enlarged view of a fiber sheet according to some aspects.

[0018] Figure 8 Shown is a schematic close-up view of another fiber sheet according to some aspects.

[0019] Figure 9 An aerogel composite sheet material according to some aspects is shown.

[0020] Figure 10 Another example of an aerogel composite sheet material according to some aspects is shown.

[0021] Figure 11 Another example of an aerogel composite sheet material according to some aspects is shown.

[0022] Figure 12 Another example of an aerogel composite sheet material according to some aspects is shown.

[0023] Figure 13 A flow chart of a method according to some aspects is shown.

[0024] Figure 14 A flow chart of another method according to some aspects is shown.

[0025] Figure 15 An electronic device according to some aspects is shown.

[0026] Figure 16 An electric vehicle according to some aspects is shown.

[0027] Figure 17 Selected operations for forming an aerogel composite according to some aspects are shown. DETAILED DESCRIPTION

[0028] The following description and accompanying drawings sufficiently illustrate specific embodiments to enable those skilled in the art to practice these specific embodiments. Other embodiments may include structural, logical, electrical, process, and other changes. Portions and features of some embodiments may be included in, or substituted for, portions and features of other embodiments. The embodiments set forth in the claims encompass all available equivalents of those claims.

[0029] The thermal insulation materials and reinforced thermal insulation materials described below can be used as a single heat-resistant layer or in combination with other layers that provide additional functionality to the multi-layer configuration, such as mechanical strength, compressibility, heat dissipation / conductivity, etc. The described thermal insulation layers are responsible for reliably containing and controlling heat flow from heat-generating components within a small space, providing safety and preventing the spread of fire in such products in the electronics, industrial, and automotive technology fields.

[0030] In various aspects of the present disclosure, the thermal insulation layer can function as a flame / fire diversion layer, either alone or in combination with other materials that enhance the containment and control of heat flow. For example, the thermal insulation layer itself can withstand flames and / or hot gases and also include entrained particulate materials that modify or enhance heat containment and control.

[0031] One aspect of a high-efficiency thermal insulation layer includes aerogels. Aerogels describe a class of materials based on their structure, i.e., low density, open honeycomb structure, large surface area (typically 900 m2 / g or greater), and sub-nanometer pore size. The pores can be filled with a gas, such as air. Aerogels can be distinguished from other porous materials based on their physical and structural properties. While aerogel materials are exemplary thermal insulation materials, the present disclosure is not limited thereto. Other thermal insulation material layers can also be used in aspects of the present disclosure.

[0032] Selected aspects of aerogel formation and properties have been described. In some aspects, a precursor material is gelled to form a network of pores filled with a solvent. The solvent is then extracted, leaving a porous matrix. A variety of different aerogel compositions are known, which can be inorganic aerogels, organic aerogels, and inorganic / organic hybrid aerogels. Inorganic aerogels are typically based on metal alkoxides and contain materials such as silicon dioxide, zirconium oxide, aluminum oxide, and other oxides. Organic aerogels include, but are not limited to, urethane aerogels, resorcinol formaldehyde aerogels, and polyimide aerogels.

[0033] Inorganic aerogels can be formed from metal oxides or metal alkoxide materials. Metal oxides or metal alkoxide materials can be based on oxides or alkoxides of any metal that can form oxides. Such metals include, but are not limited to, silicon, aluminum, titanium, zirconium, hafnium, yttrium, vanadium, cerium, and the like. Inorganic silica aerogels are traditionally prepared by hydrolysis and condensation of silica-based alkoxides (such as tetraethoxysilane), or by gelation of silicic acid or water glass. Other relevant inorganic precursor materials for the synthesis of silica-based aerogels include, but are not limited to, metal silicates (such as sodium silicate or potassium silicate), alkoxysilanes, partially hydrolyzed alkoxysilanes, tetraethoxysilane (TEOS), partially hydrolyzed TEOS, condensation polymers of TEOS, tetramethoxysilane (TMOS), partially hydrolyzed TMOS, condensation polymers of TMOS, tetra-n-propoxysilane, partially hydrolyzed and / or condensation polymers of tetra-n-propoxysilane, polyethyl silicate, partially hydrolyzed polyethyl silicate, monomeric alkylalkoxysilanes, bis-trialkoxyalkyl or aryl silanes, polyhedral silsesquioxanes, or combinations thereof.

[0034] In certain embodiments of the present disclosure, pre-hydrolyzed TEOS, such as Silbond H-5 (SBH5, Silbond Corp), which is hydrolyzed at a water / silica ratio of about 1.9-2, is commercially available or can be further hydrolyzed before incorporation into the gelation process. Partially hydrolyzed TEOS or TMOS, such as polyethyl silicate (Silbond 40) or polymethyl silicate, can also be commercially available or can be further hydrolyzed before incorporation into the gelation process.

[0035] Inorganic aerogels may also include a gel precursor containing at least one hydrophobic group, such as an alkyl metal alkoxide, a cycloalkyl metal alkoxide, and an aryl metal alkoxide, which can impart or improve certain properties in the gel, such as stability and hydrophobicity. Inorganic silica aerogels may specifically include a hydrophobic precursor, such as an alkylsilane or an arylsilane. The hydrophobic gel precursor may be used as the primary precursor material to form the framework of the gel material. However, in the formation of amalgam aerogels, the hydrophobic gel precursor is more commonly used as a co-precursor in combination with a simple metal alkoxide. Hydrophobic inorganic precursor materials for silica-based aerogel synthesis include, but are not limited to, trimethylmethoxysilane (TMS), dimethyldimethoxysilane (DMS), methyltrimethoxysilane (MTMS), trimethylethoxysilane, dimethyldiethoxysilane (DMDS), methyltriethoxysilane (MTES), ethyltriethoxysilane (ETES), diethyldiethoxysilane, dimethyldiethoxysilane (DMDES), ethyltriethoxysilane, propyltrimethoxysilane, propyltriethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane (PhTES), hexamethyldisilazane, and hexaethyldisilazane, etc. Any derivative of any of the above precursors may be used, and in particular, certain polymers of other chemical groups may be added to or cross-linked with one or more of the above precursors.

[0036] Organic aerogels are generally formed from carbon-based polymer precursors. Such polymer materials include, but are not limited to, resorcinol formaldehyde (RF), polyimides, polyacrylates, polymethyl methacrylate, acrylate oligomers, polyoxyalkylenes, polyurethanes, polyphenols, polybutadiene, trialkoxysilyl-terminated polydimethylsiloxanes, polystyrene, polyacrylonitrile, polyfurfural, melamine formaldehyde, cresol formaldehyde, phenol furfural, polyethers, polyols, polyisocyanates, polyhydroxybenzenes, polyvinyl dialdehydes, polycyanurates, polyacrylamides, various epoxy resins, agar, agarose, chitosan, and combinations thereof. In one aspect, organic RF aerogels are typically made by sol-gel polymerization of resorcinol or melamine with formaldehyde under alkaline conditions.

[0037] Organic / inorganic hybrid aerogels are primarily composed of organically modified silica ("ormosil") aerogels. These ormosil materials include an organic component covalently bonded to a silica network. Ormosils are typically formed by the hydrolysis and condensation of an organically modified silane (R—Si(OX)3) with a traditional alkoxide precursor (Y(OX)4). In these formulas, X can represent, for example, CH3, C2H5, C3H7, C4H9; Y can represent, for example, Si, Ti, Zr, or Al; and R can be any organic moiety, such as methyl, ethyl, propyl, butyl, isopropyl, methacrylate, acrylate, vinyl, epoxide, and the like. The organic component in ormosil aerogels may also be dispersed throughout or chemically bonded to the silica network.

[0038] Aerogels can be formed from flexible gel precursors. Various flexible layers (including flexible fiber-reinforced aerogels) can be easily combined and shaped to produce preforms that, when mechanically compressed along one or more axes, produce a compressively strong body along any of those axes.

[0039] One method of aerogel formation includes batch casting. Batch casting involves catalyzing the entire volume of a sol to induce gelation throughout the entire volume simultaneously. Gel formation techniques include adjusting the pH and / or temperature of a diluted metal oxide sol to a point where gelation occurs. Suitable materials for forming inorganic aerogels include oxides of most metals that can form oxides, such as silicon, aluminum, titanium, zirconium, hafnium, yttrium, vanadium, and the like. Gels formed primarily from alcoholic solutions of hydrolyzed silicates are particularly preferred because they are readily available and inexpensive (alcogels). Organic aerogels can also be prepared from melamine formaldehyde, resorcinol formaldehyde, and the like.

[0040] As mentioned above, aerogel can be an organic aerogel, an inorganic aerogel or a mixture thereof. In some aspects, aerogel comprises an aerogel based on silicon dioxide. One or more layers in the thermal barrier can comprise reinforcement. Reinforcement can be any material that provides resilience, conformability or structural stability for the aerogel material. Aspects of reinforcement include but are not limited to open honeycomb macroporous skeleton reinforcement, closed honeycomb macroporous skeleton reinforcement, open honeycomb film (for example open honeycomb foam), cellular reinforcement, polymer reinforcement and fiber reinforcement (such as discrete fibers), woven materials, nonwovens, needle-punched nonwovens, cotton batting, fiber web, pad and felt.

[0041] Reinforcement can be selected from the fiber based on organic polymer, inorganic fiber, the fiber based on carbon or their combination.Inorganic fiber is selected from glass fiber, rock fiber, metal fiber, boron fiber, ceramic fiber, basalt fiber or their combination.In some aspects, reinforcing material can comprise the reinforcement with multiple material layers.

[0042] In addition to the thermally insulating layer, the combination of the thermally conductive layer and the thermally insulating layer can effectively direct the unwanted heat to a desired external location, such as an external heat sink fin, a heat sink housing, or other external structure that dissipates the unwanted heat to a heat sink (the external location is, for example, external ambient air, a radiator, a high heat capacity mass). In one aspect, one or more thermally conductive layers help dissipate heat from localized heat loads within the battery system or battery pack. Aspects of high thermal conductivity materials include carbon fiber, graphite, silicon carbide, metals (including but not limited to copper, stainless steel, aluminum, etc.), and combinations thereof.

[0043] To aid in heat distribution and heat removal, in at least one embodiment, the thermally conductive layer is coupled to a heat sink. It should be understood that there are a variety of heat sink types and configurations, as well as different techniques for coupling a heat sink to a thermally conductive layer, and the present disclosure is not limited to the use of any one type of heat sink / coupling technique. For example, at least one thermally conductive layer of the multi-layer structure can be in thermal communication with an element of a cooling system of a battery pack system or battery pack, such as a cooling plate or cooling channel of the cooling system.

[0044] Figure 1A One aspect of a battery system 100 that may include an aerogel composite sheet material is shown. The system 100 includes one or more battery cells 102. A heat sink 104 is shown positioned on a side of the system 100 and in thermal communication with the battery cells 102. Figure 1B A cross section of a battery module 100 is shown. One or more of the cells 102 are shown separated by thermal barriers 110. Figure 1B In one embodiment, only selected groups of cells 102 are separated by thermal barriers 110, but the present disclosure is not limited in this regard. In other aspects, each cell 102 is constrained by a thermal barrier. The side surfaces, bottom surface, or top surface of the battery module 100 may also include a thermal barrier. In one aspect, the cells 102 are lithium-ion pouch cells, but the present disclosure is not limited in this regard. Lithium-ion pouch cells are often used in electric vehicle battery systems.

[0045] Figure 2 Selected components of the aerogel composite sheet material are shown. Aspects of the aerogel composite sheet material described in this disclosure can be used as Figure 1B All or a portion of the thermal barrier 110 is shown. While a thermal barrier in a battery system is used as an example, other uses besides battery devices are within the scope of the present disclosure.

[0046] exist Figure 2 , a plurality of fiber sheets 202 are shown, and the plurality of fiber sheets are arranged in a stack. In one aspect, the plurality of fiber sheets 202 comprise fiberglass yarn sheets. Fiberglass yarn sheets are readily available, very thin, and easily incorporated into the manufacturing process and products described below. While used as an effective example, the present disclosure is not limited thereto. Other fiber yarns (such as carbon fiber yarn) or other fiber weights are also within the scope of the present disclosure.

[0047] Fiberglass yarn can be distinguished from fiberglass batt in several ways. In one aspect, the fiberglass yarn has a fiber length of about 12 mm. In one aspect, the fiberglass yarn has an areal density of 2 g / m2 to 200 g / m2. In one aspect, the fiberglass yarn has an areal density of 100 g / m2. 2 Up to 250g / m 2 The area density and thickness of 0.025cm to 0.050cm. In contrast, fiberglass batts can have an area density that overlaps with fiberglass yarns, however, the thickness of fiberglass batts is 0.5cm or thicker, up to several centimeters thick.

[0048] In one aspect, fiberglass yarn is manufactured through a solution-based papermaking process in which short chopped fibers (about one inch or shorter) are held together by an organic binder. In contrast, fiberglass batt comprises longer fibers formed by pulling apart the fiber bundles with teeth or wire. The fibers in the fiberglass batt are then held together by needling or stapling, with the movement of the fibers along the Z direction holding the web together. Fiberglass yarn and fiberglass batt are considered distinct products in the industry.

[0049] Figure 3 An aerogel composite sheet material 200 is shown. The aerogel composite sheet material 200 includes a matrix 204 comprising aerogel. In one aspect, the aerogel is a monolithic aerogel matrix 204. In one aspect, the matrix 204 comprises an aerogel component, such as particles or a powder of aerogel material, mixed with a binder to form the matrix 204. As discussed above, the matrix 204 comprising aerogel has very low thermal conductivity and is particularly effective in insulating even at very thin thicknesses.

[0050] Matrix 204 is shown surrounding the fiber sheet 202. In one aspect, the matrix is ​​defined as a continuous phase that encapsulates a dispersed phase. Figure 3 In the example of FIG, the fiber sheet 202 is in the dispersed phase, and the matrix 204 is shown encapsulating the fiber sheet 202. Figure 3In the example of FIG, multiple fiber sheets 202 are stacked, however, the sheets 202 remain separate. The continuous matrix 204 is infused and penetrates between the fiber sheets 202 and into the structure (fibers, etc.) of the sheets 202.

[0051] The matrix 204 of the aerogel composite sheet material 200 includes an exterior surface 206. In one aspect, the aerogel composite sheet material 200 can be fractured along a fracture plane 210. The resulting structure is Figure 4 2 is shown as a second aerogel composite sheet 400. Once the second aerogel composite sheet 400 is separated from the composite sheet material 200, the remaining composite sheet material 400B is left. The second aerogel composite sheet 400 includes a portion of the matrix 204, the matrix including a first major surface side as the exterior surface 206, and a second major surface side including a fracture surface 212. The fracture surface 212 can be physically identified by structure (such as surface roughness, sharp edges of brittle fracture, fracture mode that follows the surface topography of the encapsulating fiber sheet 202, etc.). Figure 5B and Figure 5C An example of a fracture surface is shown in more detail in .

[0052] It is desirable to use thermal barriers reinforced with structures such as fiber sheets 202 for a variety of applications. While aerogel materials offer excellent thermal insulation, they are also fragile and prone to cracking. Using one or more fiber sheets in the form of a composite material for reinforcement helps maintain structural integrity. It is also desirable for aerogel composite sheets to have a predictable, consistent thickness. Thinner aerogel composite sheets can allow for more space for additional batteries in a battery system, thereby increasing the amount of charge that can be stored.

[0053] In manufacturing, such as Figure 4 As shown, an aerogel composite sheet material 200 can be simply manufactured by stacking multiple fiber sheets 202, and then breaking the aerogel composite sheet material into multiple second aerogel composite sheets 400. This manufacturing process is simpler and more efficient (i.e., more components are produced per unit time), and in some embodiments, can produce components that are more uniform in size and thinner than forming a single very thin aerogel composite sheet separately. In addition, this manufacturing process can be used to manufacture any of a variety of optional thicknesses of the second aerogel composite sheet 400. Figure 3The break lines 210 in the stack are selected to select one, two, three, etc., fiber sheets 202 to include in the second aerogel composite sheet 400. Selecting the location where the aerogel composite sheet material 200 breaks effectively selects the final thickness of the second aerogel composite sheet 400. Additionally, due to the controlled break lines between adjacent fiber sheets 202 in the stack, the resulting second aerogel composite sheet 400 has improved thickness consistency.

[0054] Figure 5A A third aerogel composite sheet 500 according to one aspect is shown. The third aerogel composite sheet 500 is from Figure 3 The aerogel composite sheet material 200 is located in the middle of the aerogel composite sheet material 200, and thus, includes a first fracture surface 212 and a second fracture surface 214 on opposite major surfaces of the third aerogel composite sheet 500. Although the third aerogel composite sheet 500 is shown as a single fiber sheet 202 encapsulated by the matrix 204, the present disclosure is not limited thereto. Other numbers of fiber sheets 202 may be included depending on the desired thickness of the third aerogel composite sheet 500.

[0055] Figure 5B and Figure 5C More details of an example of a fracture surface are shown. Figure 5B Shows the Figure 5A FIG. 5 is a close-up view of the end of composite sheet 510 similar to composite sheet 500 in FIG. A fiber sheet 512 is shown encapsulated by aerogel 514. Aerogel 514, by definition, includes a plurality of pores 516 present within the aerogel. A top surface 520 and a bottom surface 522 of aerogel 514 are shown. Figure 5B It is shown how each of the surfaces 520, 522 exhibits the physical characteristics of a fractured surface as discussed above. A plurality of open, fractured pores 518 can be observed on the top surface 520 and the bottom surface 522. In contrast, the edge 524 is sealed, or seals better than the fractured surfaces 520, 522 because the edge 524 cures against the sides of the mold and does not subsequently fracture. In one aspect, the fractured surfaces 520, 522 include open, fractured pores 518, while non-fractured surfaces (such as the edge 524) do not include open, fractured pores 518. In one aspect, the fractured surfaces 520, 522 include a large number or concentration of open, fractured pores 518, while non-fractured surfaces (such as the edge 524) include fewer open, fractured pores 518. This difference in physical characteristics provides, among other things, a physically different indication that the composite sheet 510 is cured by Figure 3 The composite sheet material 200 is formed by breaking a larger stack of composite sheet materials (such as composite sheet material 200).

[0056] In one aspect, the composite sheet 510 is cut from a larger composite sheet along the edge 524, so that the surface 520, the surface 522, and the edge 524 all include open, broken holes 518. However, the major surfaces (such as the top surface 520 and the bottom surface 522) will be significantly different. Figure 4 and Figures 5A to 5C The unbroken reinforced aerogel sheet shown in .

[0057] Figure 5C A close-up view of a fractured surface 532 of an aerogel in a composite sheet, such as composite sheet 510, is shown. Due to the fracture of the aerogel matrix in the composite sheet, a plurality of exposed arcuate surfaces 534 and peaks 536 are provided. In one aspect, the aerogel matrix comprises silica aerogel. The fracture characteristics of silica aerogel are particularly brittle and, upon fracture, produce physically observable features such as open, fractured pores 518 as well as arcuate surfaces 534 and peaks 536.

[0058] Figure 5D An end view 540 and a top view 550 of a composite sheet material 541 are shown. The top view 550 shows a major surface 551 of the composite sheet material 541. A plurality of stacked fiber sheets 542 are shown in the end view 540, wherein a plurality of fracture planes 544 can be observed between the plurality of stacked fiber sheets 542. In the end view 540, although the fracture planes 544 are visible, the stacked fiber sheets 542 have not yet been completely fractured from one another to form an entire major surface having fracture features spanning the entire major surface.

[0059] Figure 6 One aspect of a fiber sheet 602 that can be used in the described aerogel composite sheet is shown. Figure 6 In an embodiment of the present invention, the fibers in the fiber sheet are woven into a specific pattern. Figure 7 Another example of a fiber sheet 702 that can be used in the described aerogel composite sheet is shown. Figure 7 In the example of the fiber sheet, the fibers in the fiber sheet are non-woven and randomly oriented into a mat. Although the figure shows two fiber sheets (602, 702) of different configurations, the present disclosure is not limited thereto. Figure 6 and Figure 7Other woven fabrics, fiber densities, etc. other than the examples of are included within the scope of the present disclosure. Any of several fiber materials can be used to form fiber sheets, such as fiber sheet 202, fiber sheet 602, and fiber sheet 702. Exemplary fiber materials include, but are not limited to, glass fiber, carbon fiber, boron fiber, and combinations of glass, carbon, boron, etc. are all within the scope of the present disclosure. Another exemplary fiber includes oxidized polyacrylonitrile (OPAN) fiber. OPAN fiber has the advantages of inherent fire resistance and thermal stability, exhibits excellent chemical and solvent resistance, and is non-conductive.

[0060] Figure 8 A schematic diagram of a portion of a fiber sheet 802 according to another example is shown. In one example, the fiber sheet 802 is glass fiber yarn. Figure 8 In the example of , a binder material 812 is included at the intersection 810 between the multiple fibers in the fiber sheet 802. Examples of binder materials include, but are not limited to, polyvinyl alcohol (PVA), acrylic acid, styrene and / or combinations thereof. Binder materials at the fiber intersections are useful in nonwoven fiber sheet examples. The addition of binder materials helps to keep the fiber sheet together during encapsulation with the matrix. In some examples, a binder can be used to maintain contact at the intersections of the various fibers. This can then provide compression and / or dimensional resilience so that the fiber sheet 802 treated in this manner returns to its (approximate) shape and / or size after releasing the applied force. In some examples, the binder can be a multi-component fiber, in which one polymer has a higher melting point and the outer polymer has a lower melting point. This polymer with a lower melting point will act as a binder. When heated, it softens or melts and is bonded to any other fiber in contact with it.

[0061] Figure 9 Another example of an aerogel composite sheet material 900 is shown. Material 900 includes a plurality of individual fiber sheets arranged in a stack. Figure 9 , for illustration purposes, a first fiber sheet 902 and a second fiber sheet 904 are shown. Material 900 also includes a matrix 901 comprising an aerogel surrounding a plurality of individual fiber sheets.

[0062] Figure 9 Also shown are fiber sheets 902 and fiber sheets 904 coupled together along one or more connecting pattern elements 906. In one aspect, the connecting pattern elements can be described as quilting, but the present disclosure is not limited in this regard. A variety of different connection configurations are possible. In one aspect, the connecting pattern elements 906 comprise stitches. In one aspect, the connecting pattern elements 906 comprise a binder (such as a quilt) from within the fiber sheets 902 and 904. Figure 8The melted and recooled portion of the adhesive 812 is shown.

[0063] Figure 10 Another example of an aerogel composite sheet material 1000 is shown, comprising a fiber sheet 1002 and a fiber sheet 1004 coupled together along one or more connecting pattern elements 1006. An aerogel matrix 1001 is shown encapsulated and infused within the fiber sheets 1002 and 1004. Figure 10 In the example of the connection pattern element 1006, the connection pattern element 1006 includes a separate adhesive 1008 that forms the connection pattern element 1006. In one aspect, the adhesive 1008 can be included, and in the example Figure 8 Different binders 812 are used within the fiber sheets shown. In one aspect, the binder 1008 is selected to provide Figure 8 In one aspect, the adhesive 1008 is selected to better facilitate separation of the sheets after encapsulation with the aerogel matrix, such as Figure 3 、 Figure 4 and Figures 5A to 5C As shown. PVA has been shown to be particularly effective in providing sufficient bonding force to form a composite sheet material 200, such as Figures 10 to 12 and Figure 3 As shown, while being thin enough to provide good separation between the aerogel composite sheets, as Figure 4 and Figures 5A to 5C Although PVA is used as one aspect, the present disclosure is not limited thereto.

[0064] Any of a variety of geometries or patterns of connection pattern elements 1006 , 1008 are within the scope of the present disclosure. Figure 11 A first fiber sheet 1102 and a second fiber sheet 1104 are shown. Figure 11 A plurality of connecting pattern elements 1106 comprising lines are shown. Figure 12 A first fiber sheet 1202 and a second fiber sheet 1204 are shown. Figure 12 A plurality of connected pattern elements 1206 including dots are shown.

[0065] Fully reinforcing thicker aerogel composites can be difficult. The described multiple fiber sheet examples can be manufactured to a desired thickness based on a selected stack of fiber sheets. The sheets can be attached together as described before encapsulation with a matrix. In this way, by forming connecting pattern elements in a selected number of fiber sheets, the desired final product thickness can be selected before encapsulation with a matrix. For example, a 1 mm thick product can use one sheet, a 5 mm thick product can use 5 sheets, a 10 mm thick product can use 10 sheets, and so on. Furthermore, in one aspect, a 10 mm thick product can be separated into two separate 5 mm thick products in an intermediate layer.

[0066] There are a variety of ways to connect the pattern elements. As mentioned above, the selective placement of stitches or bonding patterns are examples of possible connection methods. In one example, each fiber sheet already includes a binder, such as Figure 8 The binder 812 in the fiber sheets is thus pressed and heated only at selected locations (lines, points, etc.). The heating causes the binder already present in the fiber sheets to form connecting pattern elements. Figure 10 As shown, additional adhesives may also be used. Although exemplary methods of forming connecting pattern elements are discussed, the present disclosure is not limited thereto. Other methods of forming connecting pattern elements are also within the scope of the present disclosure.

[0067] Figure 13 A flow chart of an exemplary method for making an aerogel composite sheet material is shown. In operation 1302, a desired thickness of the aerogel composite material is selected. In operation 1304, two or more fiber sheets are stacked, wherein the stacked plurality of fiber sheets corresponds to the desired thickness. In operation 1306, an aerogel material is incorporated into the plurality of fiber sheets, and in operation 1308, the aerogel material is cured along with the plurality of fiber sheets. As shown in the above examples, the aerogel material can be monolithic or can be a separate matrix containing aerogel particles suspended within the matrix.

[0068] In one aspect, after the aerogel material is incorporated into the plurality of fiber sheets, the aerogel material is cured along with the plurality of fiber sheets while the plurality of fiber sheets are compressed together perpendicular to the major surfaces of the stack. In this example, the thickness and surface variations of the resulting composite sheet material can be more tightly controlled.

[0069] Figure 14Another flow chart of an exemplary method for making an aerogel composite sheet material is shown. In operation 1402, two or more fiber sheets are stacked. In operation 1404, aerogel material is incorporated into the stack. In operation 1406, the aerogel material is cured with the stack to form an encapsulated stack of fiber sheets, and in operation 1408, one or more encapsulating plies are separated from the encapsulated stack of fiber sheets.

[0070] As discussed above, one end use of the described aerogel composite sheet material includes thermal barriers within battery systems. Battery systems are used in a variety of electronic devices. Figure 15 An exemplary electronic device 1500 is shown that includes a battery system 1510. The battery system 1510 is coupled to functional electronics 1520 via circuitry 1512. In the example shown, the battery system 1510 and circuitry 1512 are housed in a housing 1502. A charging port 1514 is shown coupled to the battery system 1510 to recharge the battery system 1510 when needed.

[0071] In one aspect, functional electronic device 1520 comprises a device having transistors and memory circuits, such as a semiconductor device. Examples include, but are not limited to, phones, computers, display screens, navigation systems, and the like.

[0072] Figure 16 Another electronic system utilizing a battery pack system including a multi-layer thermal barrier as described above is shown. An electric vehicle 1600 is shown in FIG. Figure 16 . Electric vehicle 1600 includes a chassis 1602 and wheels 1622. In the example shown, each wheel 1622 is coupled to a drive motor 1620. A battery system 1610 is shown coupled to the drive motors 1620 via circuitry 1606. A charging port 1604 is shown coupled to the battery system 1610 to allow recharging of the battery system 1610 when needed.

[0073] Examples of electric vehicles 1600 include, but are not limited to, consumer vehicles such as cars and trucks. Commercial vehicles such as tractors and semi-trucks are also within the scope of this disclosure. Although four-wheeled vehicles are shown in the figures, this disclosure is not limited thereto. For example, two-wheeled vehicles such as motorcycles and scooters are also within the scope of this disclosure.

[0074] Figure 17 A manufacturing method for producing an embossed laminated aerogel composite sheet material according to one aspect is shown. A system 1700 is shown that includes a plurality of source rolls 1702 of fiber sheet material 1704. The number of source rolls 1702 can be selected based on the desired thickness and / or desired reinforcement strength of the final product.

[0075] The fiber sheets 1704 are stacked together in a section 1706 and moved through an embossing roller 1710. The embossing roller 1710 includes a plurality of protrusions 1712 that apply concentrated pressure along a pattern (such as squares, triangles, lines, dots, etc.), as described in the examples above. In one aspect, the embossing roller 1710 and / or the protrusions 1712 can be heated to selectively melt or soften the binder in the fiber sheets 1704 or the fibers in the sheets themselves. In this way, the plurality of fiber sheets 1704 from the unembossed section 1706 are bonded together.

[0076] In one aspect, the embossing pattern divides the fiber sheet 1704 from the section 1706 into a plurality of cells 1708 separated by pattern elements 1709. The embossing pattern generally provides greater strength, which is more conducive to reliable transportation along the feed direction 1701. The embossing pattern on the product (such as element 1709) reduces bending by providing stress relief areas. In one aspect, the embossing pattern is selected to provide a stiff middle / flat section for each cell 1708, while also providing controlled curling at the relief location (such as element 1709).

[0077] In one aspect, the embossed pattern includes lines or other elements primarily along the feed direction 1701. Embossed pattern elements along the feed direction 1701 provide advantages such as improved tear strength.

[0078] System 1700 also includes an aerogel dispensing unit 1720. The wet sol is dispensed onto a plurality of cells 1708 and impregnated into the fiber sheet 1704. In one aspect, the embossed pattern provides channels that improve the distribution and impregnation of the wet sol into the fiber sheet 1704. The finished product can then be stored on a final roll 1730. The addition of the embossed pattern into the fiber sheet 1704 provides a more stable, stiffer reinforcement structure for the plurality of cells 1708 and improves thickness control of the final aerogel composite. This improved consistency helps improve throughput and increase manufacturing rates.

[0079] To better illustrate the methods and apparatus disclosed herein, a non-limiting list of embodiments is provided herein:

[0080] Aspect 1. An aerogel composite sheet material comprising: a fiber sheet formed from a plurality of fibers; a matrix comprising an aerogel surrounding the fiber sheet; and an exposed major surface of the composite sheet material comprising a fracture surface spanning substantially all of the exposed major surface.

[0081] Aspect 2. The aerogel composite sheet material according to aspect 1, wherein the fiber sheet comprises glass fibers.

[0082] Aspect 3. The aerogel composite sheet material according to aspect 1, wherein the fiber sheet comprises carbon fibers.

[0083] Aspect 4. The aerogel composite sheet material of aspect 1, wherein the fiber sheet comprises nonwoven fibers.

[0084] Aspect 5. The aerogel composite sheet material of aspect 4, wherein the nonwoven fibers comprise a binder holding the fibers together.

[0085] Aspect 6. The aerogel composite sheet material according to aspect 5, wherein the binder comprises polyvinyl alcohol (PVA).

[0086] Aspect 7. The aerogel composite sheet material of aspect 5, wherein the fiber length within the fiber sheet is approximately 12 mm.

[0087] Aspect 8. The aerogel composite sheet material of aspect 5, wherein the fiber sheet has an area density of 2 g / m2 to 200 g / m2.

[0088] Aspect 9. An aerogel composite sheet material comprising: a plurality of individual fiber sheets arranged in a stack, each sheet formed from a plurality of fibers; and a matrix comprising aerogel surrounding the plurality of individual fiber sheets and infused between and within the plurality of individual fiber sheets.

[0089] Aspect 10. The aerogel composite sheet material of aspect 9, wherein the plurality of individual fiber sheets comprises nonwoven fiber sheets.

[0090] Aspect 11. The aerogel composite sheet material of aspect 10, wherein the nonwoven fiber sheet comprises a binder coating the fibers within the individual sheets to hold the fibers together.

[0091] Aspect 12. The aerogel composite sheet material of aspect 9, wherein the plurality of individual fiber sheets in the stack are coupled together along one or more connection pattern elements.

[0092] Aspect 13. The aerogel composite sheet material of aspect 12, wherein the connecting pattern elements comprise lines.

[0093] Aspect 14. The aerogel composite sheet material of aspect 12, wherein the connection pattern elements comprise dots.

[0094] Aspect 15. The aerogel composite sheet material of aspect 12, wherein the connection pattern elements are formed from one or more components of the individual fiber sheets.

[0095] Aspect 16. The aerogel composite sheet material of aspect 12, wherein the connecting pattern elements are formed from a binder that is separate from the individual fiber sheets.

[0096] Aspect 17. A method of manufacturing an aerogel composite sheet material, comprising: selecting a desired thickness of an aerogel composite material; stacking two or more fiber sheets, wherein the stacked plurality of fiber sheets corresponds to the desired thickness; incorporating an aerogel material into the plurality of fiber sheets; and curing the aerogel material together with the plurality of fiber sheets.

[0097] Aspect 18. The method of aspect 17, wherein curing the aerogel material comprises curing to form a monolithic aerogel matrix around the plurality of fiber sheets.

[0098] Aspect 19. The method of aspect 17, wherein curing the aerogel material comprises curing a matrix of aerogel particles contained around the plurality of fiber sheets.

[0099] Aspect 20. The method of aspect 17, wherein incorporating aerogel material into the plurality of fiber sheets comprises retaining aerogel particles within the plurality of fiber sheets with a binder and solidifying a matrix around the plurality of fiber sheets and aerogel particles.

[0100] Aspect 21. A method of making an aerogel composite sheet material, comprising: stacking two or more fiber sheets to form a stack; incorporating an aerogel material into the stack; curing the aerogel material with the stack to form an encapsulated stack of fiber sheets; and separating one or more encapsulating plies from the encapsulated stack of fiber sheets.

[0101] Aspect 22. The method of aspect 21, wherein separating one or more encapsulant plies from the encapsulated stack of fibrous sheets comprises breaking one or more encapsulant plies from the encapsulated stack of fibrous sheets.

[0102] Aspect 23. The method of aspect 21, wherein curing the aerogel material comprises curing to form a monolithic aerogel matrix around the stack.

[0103] Aspect 24. The method of aspect 21, wherein curing the aerogel material comprises curing a matrix of aerogel particles contained around the stack.

[0104] Aspect 25. The method of aspect 21, wherein incorporating aerogel material into the stack comprises retaining aerogel particles in the stack with a binder and solidifying a matrix around the stack and aerogel particles.

[0105] Aspect 26. A battery pack system comprising: a stack of lithium-ion batteries; a thermal barrier positioned between batteries in the stack of lithium-ion batteries, the thermal barrier comprising a composite sheet material comprising: a fiber sheet formed from a plurality of fibers; a matrix comprising an aerogel surrounding the fiber sheet; and an exposed major surface of the composite sheet material comprising a fracture surface spanning substantially all of the exposed major surface.

[0106] Aspect 27. A battery pack system comprising: a stack of lithium-ion batteries; a thermal barrier positioned between batteries in the stack of lithium-ion batteries, the thermal barrier comprising: a plurality of individual fiber sheets arranged in a stack, each sheet formed from a plurality of fibers; and a matrix comprising an aerogel surrounding the plurality of individual fiber sheets.

[0107] The above description is intended to be illustrative and not restrictive. For example, the above examples (or one or more aspects thereof) can be used in combination with each other. Other embodiments may be used by a person of ordinary skill in the art after reading the above description. The abstract of the specification complies with the provisions of 37 CFR § 1.72 (b) so that the reader can quickly determine the nature of the technical disclosure. It should be understood that the submission of the abstract is not used to interpret or limit the scope or meaning of the claims. In addition, in the above-mentioned detailed description, various features can be combined together to simplify the disclosure. This should not be interpreted as an intention to use unclaimed disclosed features as essential factors for any claim. On the contrary, the subject matter of the present invention may be less than all the features of the particularly disclosed embodiments. Therefore, the following claims are hereby incorporated into the detailed description, wherein each claim is independently a separate embodiment, and it is envisaged that such embodiments can be combined with each other in various combinations or arrangements. The scope of the present invention should be determined with reference to the appended claims and the full scope of equivalents to which these claims are entitled.

[0108] Although an overview of the subject matter of the present invention has been described with reference to certain aspects, various modifications and changes may be made to these embodiments without departing from the broader scope of the embodiments of the present disclosure. Such embodiments of the subject matter of the present invention may be referred to herein, individually or collectively, as the term "invention," which is merely for convenience and is not intended to voluntarily limit the scope of this application to any single disclosure or inventive concept if more than one disclosure or inventive concept is actually disclosed.

[0109] The embodiments shown herein are described in sufficient detail to enable those skilled in the art to practice the disclosed teachings. Other embodiments may be used and derived therefrom so that structural and logical substitutions and changes may be made without departing from the scope of the present disclosure. Therefore, the detailed description should not be taken in a limiting sense, and the scope of the various embodiments is defined solely by the appended claims and the full scope of equivalents to which such claims are entitled.

[0110] As used herein, the term "or" may be interpreted as inclusive or exclusive. In addition, multiple examples may be provided for a resource, operation, or structure described herein as an example. In addition, the boundaries between various resources, operations, systems, engines, and data stores are somewhat arbitrary, and specific operations are described in the context of specific illustrative configurations. Other functional allocations are envisioned, and the other functional allocations may be within the scope of various embodiments of the present disclosure. In general, structures and functions provided as separate resources in the exemplary configurations may be implemented as combined structures or resources. Similarly, structures and functions provided as separate resources may be implemented as separate resources. These and other changes, modifications, additions, and improvements are within the scope of the embodiments of the present disclosure as represented by the appended claims. Therefore, the description and drawings are to be regarded as illustrative rather than restrictive.

[0111] For purposes of explanation, the foregoing description has been described with reference to specific aspects. However, the illustrative discussion above is not intended to be exhaustive or to limit the possible aspects to the precise forms disclosed. Numerous modifications and variations are possible in light of the above teachings. These aspects have been selected and described in order to best explain the principles involved and their practical application, thereby enabling others skilled in the art to best utilize the various aspects with various modifications as appropriate for the specific use contemplated.

[0112] It should also be understood that although the terms "first," "second," etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are merely used to distinguish one element from another. For example, a first contact may be referred to as a second contact, and similarly, a second contact may be referred to as a first contact, without departing from the scope of the present invention. The first contact and the second contact are both contacts, but they are not the same contact.

[0113] The terms used in describing aspects herein are only used for the purpose of describing specific aspects and are not intended to be limiting. As used in the description of aspects and the accompanying examples, unless the context clearly indicates otherwise, the singular forms "a", "an", and "the" are also intended to include the plural forms. It should also be understood that, as used herein, the term "and / or" refers to and covers any and all possible combinations of one or more of the relevant listed items. It should also be understood that when the terms "comprise" and / or "comprising" are used in this specification, the presence of the specified features, wholes, steps, operations, elements and / or components is specified, but the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or groups thereof is not excluded.

[0114] As used herein, the term "if" may be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined" or "if [stated condition or event] is detected" may be interpreted to mean "upon the determination" or "in response to the determination" or "upon detecting [stated condition or event]" or "in response to detecting [stated condition or event]," depending on the context.

Claims

1. An aerogel composite sheet material, comprising: A fiber sheet formed from a plurality of fibers; a matrix comprising an aerogel surrounding the fiber sheet; as well as An exposed major surface of the composite sheet material includes a fracture surface spanning substantially all of the exposed major surface.

2. The aerogel composite sheet material of claim 1, wherein the fiber sheet comprises glass fibers.

3. The aerogel composite sheet material of claim 1, wherein the fiber sheet comprises carbon fibers.

4. The aerogel composite sheet material of claim 1, wherein the fiber sheet comprises nonwoven fibers.

5. The aerogel composite sheet material of claim 4, wherein the nonwoven fibers comprise a binder holding the fibers together.

6. The aerogel composite sheet material of claim 5, wherein the binder comprises polyvinyl alcohol (PVA).

7. The aerogel composite sheet material of claim 5, wherein the fiber length within the fiber sheet is about 12 mm.

8. The aerogel composite sheet material of claim 5, wherein the fiber sheet has an area density of 2 to 200 g / m2.

9. An aerogel composite sheet material, comprising: a plurality of individual fiber sheets arranged in a stack, each sheet being formed from a plurality of fibers; as well as A matrix comprising an aerogel surrounding the plurality of individual fiber sheets and infused between and within the plurality of individual fiber sheets.

10. The aerogel composite sheet material of claim 9, wherein the plurality of individual fiber sheets comprise nonwoven fiber sheets.

11. The aerogel composite sheet material of claim 10, wherein the nonwoven fiber sheet comprises a binder coating the fibers within the individual sheets to hold the fibers together.

12. The aerogel composite sheet material of claim 9, wherein the plurality of individual fiber sheets in the stack are coupled together along one or more connection pattern elements.

13. The aerogel composite sheet material of claim 12, wherein the connecting pattern elements comprise lines.

14. The aerogel composite sheet material of claim 12, wherein the connection pattern elements comprise dots.

15. The aerogel composite sheet material of claim 12, wherein connection pattern elements are formed from one or more components of the individual fiber sheets.

16. The aerogel composite sheet material of claim 12, wherein the connecting pattern elements are formed from a binder that is separate from the individual fiber sheets.

17. A method for manufacturing an aerogel composite sheet material, comprising: selecting the desired thickness of the aerogel composite; stacking two or more fiber sheets, wherein the stacked plurality of fiber sheets corresponds to a desired thickness; incorporating an aerogel material into the plurality of fiber sheets; as well as The aerogel material is cured together with the plurality of fiber sheets.

18. The method of claim 17, wherein curing the aerogel material comprises curing to form a monolithic aerogel matrix around the plurality of fiber sheets.

19. The method of claim 17, wherein curing the aerogel material comprises curing a matrix of aerogel particles contained around the plurality of fiber sheets.

20. The method of claim 17, wherein incorporating aerogel material into the plurality of fiber sheets comprises retaining aerogel particles within the plurality of fiber sheets with a binder and solidifying a matrix around the plurality of fiber sheets and aerogel particles.

21. A method for manufacturing an aerogel composite sheet material, comprising: stacking two or more fiber sheets to form a stack; incorporating an aerogel material into the stack; curing the aerogel material with the stack to form an encapsulated stack of fiber sheets; as well as One or more encapsulant plies are separated from the encapsulated stack of fiber sheets.

22. The method of claim 21, wherein separating one or more encapsulant plies from the encapsulated stack of fibrous sheets comprises breaking one or more encapsulant plies from the encapsulated stack of fibrous sheets.

23. The method of claim 21, wherein curing the aerogel material comprises curing to form a monolithic aerogel matrix around the stack.

24. The method of claim 21, wherein curing the aerogel material comprises curing a matrix of aerogel particles contained around the stack.

25. The method of claim 21, wherein incorporating aerogel material into the stack comprises retaining aerogel particles in the stack with a binder and solidifying a matrix around the stack and aerogel particles.

26. A battery pack system comprising: stacking of lithium-ion batteries; A thermal barrier positioned between cells in the stack of lithium-ion batteries, the thermal barrier comprising a composite sheet material comprising: A fiber sheet formed from a plurality of fibers; a matrix comprising an aerogel surrounding the fiber sheet; and An exposed major surface of the composite sheet material includes a fracture surface spanning substantially all of the exposed major surface.

27. A battery pack system comprising: stacking of lithium-ion batteries; a thermal barrier positioned between cells in the stack of lithium-ion cells, the thermal barrier comprising: a plurality of individual fiber sheets arranged in a stack, each sheet being formed from a plurality of fibers; as well as A matrix comprising an aerogel surrounding the plurality of individual fiber sheets.

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