Battery thermal barrier and battery module using same

Abstract

The utility model relates to a battery thermal barrier and a battery module using the same. Various disclosed embodiments relate to structural features in the thermal barrier. The present disclosure includes a battery module having a stack of battery cells within a module housing and a thermal barrier between at least two cells in the stack of battery cells. The thermal barrier may include an isolation layer and structural features distributed in the isolation layer. A thermal barrier for a battery module may include an isolation layer configured to thermally isolate individual battery cells within the battery module; and structural features distributed within the isolation layer.

Description

[0001] Priority claim

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 434,010, filed on December 20, 2022, entitled Enhanced Battery Thermal Barriers and Methods, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure generally relates to materials and systems for preventing or mitigating thermal events such as thermal runaway problems in energy storage systems. Specifically, the present disclosure provides thermal barrier materials. The present disclosure also relates to a battery module or battery pack having one or more battery cells containing the thermal barrier material, and a system including those battery modules or battery packs. In general, the examples described may include aerogel materials. Background Art

[0004] 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 because LIBs have high operating voltages, low memory effects, and high energy density compared to conventional batteries. However, safety is an issue because LIBs are susceptible to catastrophic failure under "abuse conditions" such as when rechargeable batteries are overcharged, over-discharged, operated at or exposed to high temperatures and voltages.

[0005] To prevent such cascading thermal runaway events, effective isolation and heat dissipation strategies are needed to address these and other technical challenges of LIBs. Utility Model Content

[0006] In one embodiment, a battery module includes a battery cell stack within a module housing; and a thermal barrier between at least two cells in the battery cell stack, the thermal barrier including an isolation layer and structural features distributed in the isolation layer.

[0007] In one embodiment, a thermal barrier for a battery module may include an insulation layer including aerogel, the insulation layer configured to thermally isolate individual battery cells within the battery module; and structural features distributed within the insulation layer.

[0008] In one embodiment, a method of manufacturing a structural feature in a thermal barrier may include removing a portion of the thermal barrier to form one or more cavities; and forming the structural feature in the one or more cavities.

[0009] In one embodiment, a method of fabricating a structural feature in a thermal barrier including a spacer may include forming the structural feature and inserting the aerogel into and around the structural feature. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In the drawings, which are not necessarily drawn to scale, the same reference numerals may describe similar components in different views. Similar numbers with different letter suffixes may represent different illustrations of similar components. The drawings generally illustrate various embodiments discussed in this document by way of example and not limitation.

[0011] Figures 1A to 1B A battery module in an embodiment is shown.

[0012] Figures 2A to 2B An example battery module having battery cells and a thermal barrier is depicted in an example embodiment.

[0013] Figures 3A to 3C A side view of an embodiment of a thermal barrier made of an aerogel having structural features in an embodiment is shown.

[0014] Figures 4A to 4C An example depicting how structural features may be applied to an aerogel in a thermal barrier in an example embodiment.

[0015] Figures 5A to 5D Embodiments of thermal barriers having various structural features are depicted in the embodiments.

[0016] Figures 6A to 6C A cross-sectional view of a thermal barrier having curved ribbon-like structural features extending the thickness of the thermal barrier is shown in an embodiment.

[0017] Figures 7A to 7C Various views of a thermal barrier featuring a flexible fiber structure are shown in an embodiment.

[0018] Figures 8A to 8B Various views of a thermal barrier having heat pressed structural features in an embodiment are shown.

[0019] Figures 9A to 9B A view showing a thermal barrier having structural features in an embodiment.

[0020] Figures 10A to 10C A view showing a thermal barrier having heat pressed structural features in an embodiment.

[0021] Fig.11 A flow chart showing a method of manufacturing a thermal barrier having structural features in an embodiment.

[0022] Main component symbols

[0023] 100 Battery Modules

[0024] 102,210 battery cells

[0025] 104 Radiator

[0026] 106 Module housing

[0027] 108 Module cover

[0028] 110,220,320,400,500,600,700,800,900,1000 Thermal barrier

[0029] 112 Support plate

[0030] 114 Module cover contacts

[0031] 118 Thermal insulation layer

[0032] 120 Second thermal insulation layer

[0033] 130 Space

[0034] 205 First principal plane

[0035] 215 Second principal plane

[0036] 222,322,422,722 Aerogel

[0037] 224,324,424,524B,525A,624,724,824,924,1024 Structural features

[0038] 225 Thickness

[0039] 226,826 Components

[0040] 326 bars

[0041] 423 Cavity

[0042] 1025 Edge

[0043] 1100 Methods

[0044] 1110,1120 frame DETAILED DESCRIPTION

[0045] The following description and the accompanying drawings sufficiently illustrate the specific embodiments to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process and other changes. Portions and features of some embodiments may be included in or replace portions and features of other embodiments. The embodiments set forth in the claims encompass all available equivalents of those claims.

[0046] The present disclosure describes, among other things, systems and methods related to thermal barriers for battery modules. The thermal barriers may be aerogel-based thermal barriers such as those used inside or around battery modules. Discussed herein, among other things, are the creation and use of structural features within such thermal barriers to impart shear strength and compressibility to the thermal barriers.

[0047] Thermal barriers, which may include thermal isolation layers and structures, may be used in battery modules to help regulate temperature and heat flow within such battery modules. For example, lithium-ion batteries are typically used in stacks of many battery cells, which may benefit from thermal regulation to prevent thermal runaway that may result in potential fire, overheating, combustion, or other problems associated with high temperatures in such battery modules.

[0048] Such thermal barriers may be made of thermal insulation materials such as aerogel materials discussed in detail below. Insulation materials according to exemplary embodiments disclosed herein include ceramic materials, such as ceramic paper; mica materials; polymer foam materials, such as polyurethane foam, polyisocyanurate foam, polystyrene foam, and phenolic foam; polymer sheets, such as polypropylene sheets, polystyrene sheets, and polyisocyanurate sheets; microporous silica; ceramic fibers; mineral wool; multilayer materials, including insulating, conductive, and / or compressive elements; glass fibers; rubber, cementitious foam, perlite materials; and combinations thereof. Although these materials provide thermal benefits, they may be subject to mechanical stresses, such as within a battery cell stack. In this case, when the thermal barrier is located, for example, between two battery cells, a large amount of shear stress may be applied to the thermal barrier. In addition, the material from which the thermal barrier is made may not have the compressibility desired for large battery stacks. Mechanical degradation and / or failure of the thermal barrier may lead to failure of such battery stacks.

[0049] To this end, discussed herein is the use of structural features within a thermal barrier. Structural features can be inserted into and around the aerogel of the thermal barrier to impart shear strength and compressibility. For example, structural features can include points, rods, tubes, grids, nets, strips, frames, or other suitable shapes that support the structural integrity of the aerogel. These structural features can be created first, and then the aerogel is inserted around them. Alternatively, these structural features can be formed within an already formed aerogel. These structural features can be made of polymer or plastic materials, or dielectric materials, such as polyimide, polycarbonate, polyester, or other suitable materials with suitable electrical and thermal properties.

[0050] As described in the following aspects, thermal barrier insulation materials can be used as a single heat-resistant layer or in combination with other layers to provide additional functionality to multi-layer constructions, such as mechanical strength, compressibility, heat dissipation / heat conduction, etc. The insulation layers described herein are responsible for reliably containing and controlling heat flow from heat-generating components in confined spaces, as well as providing safety and preventing the spread of fire for such products in the fields of electronics, industrial, and automotive technology.

[0051] In many embodiments of the present disclosure, the insulation layer itself is used alone as a flame / fire deflector layer, or is used in combination with other materials that enhance the performance of containing and controlling heat flow. For example, the insulation layer itself is resistant to flames and / or hot gases, and also includes entrained particulate materials that change or enhance heat containment and control.

[0052] Highly efficient insulation layers may include aerogels. Aerogels describe a class of materials based on their structure, i.e. low density, open pore structure, large surface area (typically 900 m 2 / g or higher) and sub-nanometer pore size. The pores may be filled with a gas such as air. Aerogels can be distinguished from other porous materials by their physical and structural properties. Although aerogel materials are exemplary insulation materials, the present invention is not limited thereto. In various aspects of the present disclosure, other thermal insulation material layers may also be used.

[0053] Selected aspects of aerogel formation and properties are described. In several 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, and they may be inorganic, organic, and inorganic / organic hybrids. Inorganic aerogels are typically based on metal alkoxides and include materials such as silicon dioxide, zirconium oxide, aluminum oxide, and other oxides. Organic aerogels include, but are not limited to, polyurethane aerogels, resorcinol formaldehyde aerogels, and polyimide aerogels.

[0054] Inorganic aerogels may be formed from metal oxide or metal alkoxide materials. Metal oxide or metal alkoxide materials may be based on oxides or alkoxides of any metal that can form an oxide. Such metals include, but are not limited to, silicon, aluminum, titanium, zirconium, hafnium, yttrium, vanadium, cerium, etc. Inorganic silica aerogels are traditionally made 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 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 tetra-n-propoxysilane and / or condensation polymers of tetra-n-propoxysilane, polyethyl silicate, partially hydrolyzed polyethyl silicate, monomeric alkylalkoxysilanes, bistrialkoxyalkyl or aryl silanes, polyhedral silsesquioxanes, or combinations thereof.

[0055] In certain embodiments of the present disclosure, pre-hydrolyzed TEOS, such as Silbond H-5 (SBH5, Silbond Corp) hydrolyzed at a water / silica ratio of about 1.9 to 2, may be used in a commercially available form, or may be further hydrolyzed prior to introduction into the gelation process. Partially hydrolyzed TEOS or TMOS, such as polyethyl silicate (Silbond 40) or polymethyl silicate, may also be used in a commercially available form, or may be further hydrolyzed prior to introduction into the gelation process.

[0056] Inorganic aerogels may also include a gel precursor comprising at least one hydrophobic group, such as an alkyl metal alkoxide, a cycloalkyl metal alkoxide, and an aryl metal alkoxide, which may impart or improve specific properties of the gel, such as stability and hydrophobicity. Inorganic silica aerogels may specifically include a hydrophobic precursor, such as an alkyl silane or an aryl silane. The hydrophobic gel precursor may be used as a primary precursor material to form a skeleton of the gel material. However, when forming a hybrid aerogel (amalgam aerogel), the hydrophobic gel precursor is usually combined with a simple metal alkoxide and used as a co-precursor. 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 polymeric other chemical groups may be added to or cross-linked to one or more of the above precursors.

[0057] Organic aerogels are usually formed from carbon-based polymer precursors. Such polymer materials include, but are not limited to, resorcinol-formaldehyde (RF), polyimide, polyacrylate, polymethyl methacrylate, acrylate oligomers, polyoxyalkylenes, polyurethanes, polyphenols, polybutane, trialkoxysilyl-terminated polydimethylsiloxane, polystyrene, polyacrylonitrile, polyfurfural, melamine formaldehyde, cresol-formaldehyde, phenol-furfural, polyethers, polyols, polyisocyanates, polyhydroxybenzenes, polyvinyl alcohol dialdehyde, polycyanurate, polyacrylamide, various epoxy resins, agar, agarose, chitosan, and combinations thereof. As an example, organic RF aerogels are usually prepared by sol-gel polymerization of resorcinol or melamine with formaldehyde under alkaline conditions.

[0058] Organic / inorganic hybrid aerogels are mainly composed of (organically modified silica ("Ormosil") aerogels. These organically modified silica materials contain organic components covalently bonded to the silica network. Organically modified silica is usually formed by hydrolysis and condensation of organically modified silanes, R-Si(OX)3, and traditional alkoxide precursors Y(OX)4. In these formulas, X may represent CH3, C2H5, C3H7, C4H9; Y may represent Si, Ti, Zr or Al; and R may be any organic fragment, such as methyl, ethyl, propyl, butyl, isopropyl, methacrylate, acrylate, vinyl, epoxide, etc. The organic components in the organically modified silica aerogel may also be dispersed throughout the silica network or chemically bonded to the silica network.

[0059] 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 compressively strong bodies along any of these axes.

[0060] A method for forming an aerogel includes batch casting. Batch casting includes catalyzing the entire volume of the sol to induce gelation simultaneously throughout the volume. The gel formation technique includes adjusting the pH and / or temperature of the dilute 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, etc. Gels formed primarily from alcoholic solutions of hydrolyzed silicates are readily available and inexpensive (alcogels), so they are particularly preferred. Organic aerogels can also be made from melamine formaldehyde, resorcinol formaldehyde, etc.

[0061] In one aspect, the aerogel material may be monolithic or continuous throughout the structure or layer. In other aspects, the aerogel material may include a composite aerogel material having aerogel particles mixed with a binder. Other additives may be included in the composite aerogel material, including but not limited to surfactants that help disperse the aerogel particles in the binder. The composite aerogel slurry may be applied to a support plate, such as a mesh, felt, net, etc., and then dried to form a composite aerogel structure.

[0062] As mentioned above, aerogel may be organic, inorganic or a mixture thereof. In some aspects, aerogel includes a silica-based aerogel. One or more layers in the thermal barrier may include a reinforcing material. The reinforcing material may be any material that provides elasticity (resilience), compliance (conformability) or structural stability for the aerogel material. Aspects of the reinforcing material include but are not limited to open-cell macroporous framework reinforcing materials, closed-cell macroporous framework reinforcing materials, open-cell membranes, honeycomb reinforcing materials, polymer reinforcing materials and fiber-reinforced materials such as discrete fibers, woven materials, nonwoven materials, needle-made nonwoven materials, cotton batting, mesh fabrics, mats and felts.

[0063] The reinforcement material can be selected from organic fibers, inorganic fibers, carbon-based fibers or combinations thereof based on polymers. The inorganic fibers are selected from glass fibers, rock fibers, metal fibers, boron fibers, ceramic fibers, basalt fibers or combinations thereof. In some aspects, the reinforcement material can include a reinforcement material containing multiple material layers.

[0064] In addition to the thermal isolation 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, heat sink shell or other external structure to dissipate the unwanted heat to the external ambient air. In one embodiment, one or more thermally conductive layers help dissipate heat from local heat loads within the battery module or battery pack. Examples of high thermal conductivity materials include carbon fiber, graphite, silicon carbide, metals, and combinations thereof, including but not limited to copper, stainless steel, aluminum, etc.

[0065] To help distribute and remove heat, in at least one embodiment, the heat conductive layer may be 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 heat 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 heat conductive layer of the multilayer material disclosed herein may be thermally connected to an element of a cooling system of a battery module or battery pack, such as a cooling plate or cooling channel of a cooling system. For another example, at least one heat conductive layer of the multilayer material disclosed herein may be thermally connected to other elements of a battery pack, battery module, or battery system that can be used as a heat sink, such as a wall of a battery pack, battery module, or battery system, or, thermally connected to other elements of other multilayer materials disposed between battery cells. The thermal connection between the heat conductive layer of the multilayer material within the battery system and the heat sink element can allow excess heat to be transferred from one or more battery cells adjacent to the multilayer material to the heat sink, thereby reducing the effects, severity, or propagation of thermal events that can generate excessive heat.

[0066] Figures 1A to 1B A battery module 100 in an embodiment is shown. Figure 1A One aspect of a battery module 100 is shown. The module 100 includes a stack of battery cells 102. In one embodiment, the stack of cells 102 includes lithium-ion cells 102. There are several possible configurations of lithium-ion cells 102. In one embodiment, although the invention is not limited thereto, the stack of lithium-ion cells 102 includes lithium-ion pouch cells. A heat sink 104 is shown located on one side of the module 100 and is in thermal communication with the battery cells 102. Figure 1A In the embodiment of FIG. 1 , the stack of battery cells 102 is located within a module housing 106 . A module cover 108 is further shown enclosing the stack of battery cells 102 within the module housing 106 .

[0067] The thermal barrier 110 is shown between at least two cells in the stack of battery cells 102. In an embodiment, although the invention is not limited thereto, a thermal barrier 110 may be included between each cell in the stack of battery cells 102. In one embodiment, the thermal barrier 110 separates groups of cells 102. In the event of a thermal runaway event in one or more cells 102, the inclusion of the thermal barrier 110 provides a degree of increased safety. If a thermal runaway event occurs, the area affected by the destruction of the failed cell 102 is contained within the area between the thermal barrier 110 and / or the module housing 106. Especially in the event of a thermal runaway event in one or more individual cells 102, an improved thermal barrier 110 is needed to better separate and protect adjacent areas within the battery module 100.

[0068] Figure 1A 1. Aspects of the heat sink 104 include, but are not limited to, passive heat sinks such as metal plates and active heat sinks such as fluid recirculation systems that move heat to a remote location. Figure 1A In one embodiment, the heat shield 110 interlocks with the heat sink within the groove or other recess. In one embodiment, the heat sink 104 is a separate component contained within the module housing 106. In one embodiment, the heat sink 104 is integrated with the bottom surface of the module housing 106.

[0069] Figure 1B Show Figure 1A 1 is a cross-sectional view of a battery module 100. The thermal barrier 110 is shown to include a structural support plate 112. The thermal barrier 110 also includes a module cover contact 114 located on the top end of the structural support plate 112. The thermal isolation layer 118 is shown coupled to one side of the structural support plate 112. Figure 1B In the aspect of FIG. 1 , second thermal isolation layer 120 is shown coupled to a side of structural support plate 112 opposite thermal isolation layer 118 .

[0070] like Figure 1BAs shown, thermal barriers 110 separate at least some of the cells 102. A space 130 is shown above the cells 102 within the module housing 106 and the module cover 108. In the event of thermal runaway, gases may be vented into the space above the cells 102. In one aspect, the cells 102 include vents (not shown) specifically to direct gases into the space 130. In this event, it is desirable to contain the hot gases and prevent them from affecting adjacent cells 102.

[0071] Figure 1A and Figure 1B The battery module 100 may include a thermal barrier having one or more structural features integrated into the thermal barrier. These structural features may be integrated into the thermal barrier in various configurations, as described below.

[0072] FIG. 2A to FIG. 2B An embodiment battery module 200 is depicted having battery cells 210 and thermal barriers 220. Thermal barriers 220 may be single-layer or multi-layer. Thermal barriers 220 may each be located between two battery cells 210. Embodiment thermal barriers 220 may include aerogel 222 and structural features 224, which include a plurality of elements 226. In some cases, elements 226 may be rods, bars, dots, or other suitable shapes.

[0073] Here, the battery module 200 may be a stack of battery cells 210 within a shell. The thermal barrier 220 may be an aerogel material located between adjacent battery cells 210. The thermal barrier 220 may be subjected to shear stresses due to its location between the battery cells 210. That is, the thermal barrier 220 may be subjected to forces that tend to cause the material to deform by sliding along one or more planes parallel to the applied stress.

[0074] The thermal barriers 220 may each include a first major plane 205 extending along the largest surface of the thermal barrier. In one aspect, the first major plane 205 may face one of the battery cells 210. The thermal barriers 220 may include a second major plane 215 relative to the first major plane 205. The thermal barriers 220 may have a thickness 225 extending between the first major plane 205 and the second major plane 215.

[0075] Elements 226 of structural features 224 may be embedded in thickness 225 of thermal barrier 220. Structural features 224 may be distributed within aerogel 222 of thermal barrier 220. Each element 226 of structural features 224 may be located within aerogel 222. Elements 226 may be located perpendicular to first principal plane 205 and / or second principal plane 215 of thermal barrier 220.

[0076] Structural features 224, elements 226, may each extend through the thickness 225 of the aerogel 222 from one side of the thermal barrier 220 on the first major plane 205 to the other opposite side of the thermal barrier 220 on the second major plane 215. The length of these elements 226 may be equal to or greater than the thickness 225 of the aerogel 222.

[0077] The structural features 224 may provide greater shear forces against adjacent battery cells 210 than a thermal barrier 220 without such structural features 224. In the event that the thermal barrier 220 is laminated, the structural features 224 may provide support to the laminated thermal barrier 220 from delamination.

[0078] FIG. 3A to FIG. 3C A side view of an embodiment of a thermal barrier 320 made of an aerogel 322 having structural features 324 is shown. Here, the structural features 324 may be distributed throughout the aerogel 322 of the thermal barrier 320. The thermal barrier 320 may be single layer or multi-layer.

[0079] Each structural feature 324 may penetrate at least a portion of the thickness of the thermal barrier 320. Each structural feature 324 may have a length equal to or greater than the thickness of the thermal barrier 320. The structural features 324 may provide greater shear forces against the battery cells (or other structures) than the surface of the thermal barrier 320 without the structural features 324. Similarly, the structural features 324 may provide layered support for any laminated thermal barrier 320. Here, the structural features 324 may be individual rods 326 perpendicular to the largest surface of the thermal barrier 320.

[0080] like Figure 3A and Figure 3B As shown, structural features 324 may extend through the thickness of thermal barrier 320. Figure 3A The structural features shown in Figure 3B In the case of aerogel 322, structural features 324 may be more densely located within aerogel 322. Individual rods 326 pin the laminated layers of thermal barrier 320 together, thereby preventing thermal barrier 320 from delaminating.

[0081] like Figure 3C As shown, the structural features 324 can extend partially through the thermal barrier 320. The structural features 324 can be inserted on either side of the thermal barrier 320. Here, this can help prevent heat conduction along the single rod 326 through the thickness of the thermal barrier 320. The structural features 324 can be inserted alternately from both sides of the thermal barrier 320 to provide better compressibility. Compared to the thermal barrier 320, the structural features 324 can have less compressibility.

[0082] The structural features 324 in the thermal barrier 320 can be over-molded into or onto the thermal barrier 320. The structural features 324 can be dots, bars, or strips. The final shape of the structural features 324 over-molded into or onto the thermal barrier 320 can be flatter than the initial shape of the structural features 324.

[0083] FIG. 4A to FIG. 4C An embodiment depicting how structural features 424 may be applied to aerogel 422 in thermal barrier 400. For example, in Figure 4A , an exploded view of thermal barrier 400 shows aerogel 422 having various vertical cavities 423 for vertically placing structural features 424 therein. Figure 4B An embodiment of a thermal barrier 400 is shown having a horizontal cavity for horizontally placing a structural feature 424 therein.

[0084] FIG. 5A to FIG. 5D An embodiment of a thermal barrier 500 is depicted having various structural features 524. Figure 5A and Figure 5B In the embodiment of the present invention, the structural features 524A can be curved or wavy bands extending laterally along or within the thermal barrier 500. For example, the structural features 524A can be similar in shape to a sine wave along the surface of the thermal barrier 500. Figure 5B In the embodiment of the present invention, the structural feature 524A may include a plurality of bands, such as two curved bands aligned perpendicularly to each other on or facing the surface of the thermal barrier 500.

[0085] In such Figure 5C and Figure 5D As shown, structural feature 524B may be in the shape of a frame, such as a rectangular frame or a square frame around the edge of thermal barrier 500 on its surface. In some cases, structural feature 524B may include multiple frames, such as Figure 5D The double frame shown in .

[0086] FIG. 6A to FIG. 6C Various views of thermal barrier 600 are shown having curved band structural features 624 extending through the thickness of thermal barrier 600. The curved band structural features may not be parallel to the surface of thermal barrier 600. For example, the curved band structural features may be parallel to the surface of thermal barrier 600. Fig. 6A and Figure 6BThe largest surface of the thermal barrier 600 is shown to form an angle of 45°. Here, the various structural features 624 may include a serration extending along the thickness of the thermal barrier 600. In some aspects, the various structural features 624 may form an acute angle (e.g., 45°) or an obtuse angle (e.g., 135°) with the largest surface of the thermal barrier 600. In some cases, the various structural features 624 may form an acute angle (e.g., 45°) or an obtuse angle (e.g., 135°) with a smaller surface of the thermal barrier 600.

[0087] In some cases, various structural features 624 can have a thickness similar to thermal barrier 600. In some cases, when the structural features are curved bands, various structural features 624 can be curved so that the peaks of the curved bands are adjacent to and / or extend through the surface of thermal barrier 600. Various structural features 624 can provide better compressibility along the thickness direction of thermal barrier 600.

[0088] Figures 7A to 7C Various views of a thermal barrier 700 with flexible fiber structural features 724 are shown. In this regard, the flexible fiber structural features 724 can be made of fibers stitched through the aerogel 722 of the thermal barrier 700. The flexible fiber structural features 724 can be located on the surface of the thermal barrier 700. The flexible fiber structural features 724 can provide shear forces relative to adjacent cells and prevent the thermal barrier 700 from sliding relative to those cells. In some cases, the flexible fiber structural features 724 can be stitched vertically relative to the surface of the thermal barrier 700. In some cases, the flexible fiber structural features 724 can be stitched horizontally relative to the surface of the thermal barrier 700. In some cases, the flexible fiber structural features 724 can be inclined relative to the surface of the thermal barrier 700. Figure 7B Structural features 724 are shown stitched through the laminated thermal barrier 700 .

[0089] Figures 8A to 8B Various views of thermal barrier 800 are shown with heat pressed structural features 824. In this case, multiple elements 826 can constitute a single structural feature 824, such as by pressing the elements together to form a web or sheet. In some cases, a surface portion of structural feature 824 can extend beyond the surface of thermal barrier 800. In some cases, a portion of structural feature 824 can remain unaffected by heat pressing.

[0090] Figures 9A to 9B A view of a thermal barrier 900 is shown with a structural feature 924. A portion of the structural feature 924 may be pressed into a tie layer. The tie layer may be located on an outer surface of the thermal barrier 900 and may increase shear forces between the thermal barrier 900 and adjacent battery cells.

[0091] Figures 10A to 10CA view of a thermal barrier 1000 is shown with a heat pressed structural feature 1024. In this regard, the structural feature 1024 can have a thinner edge 1025 relative to the center of the structural feature 1024. This can allow for additional space in and around the edge of the thermal barrier 1000 when needed, such as a tab area near an adjacent battery cell. The heat pressed portion of the structural feature 1024 at the thinner edge can help maintain a thinner thickness and prevent springing back to the original thickness.

[0092] Fig.11 Flowchart showing a method of making a thermal barrier with structural features. For example, method 1100 may include removing a portion of an aerogel in a thermal barrier to form one or more cavities (block 1110), and forming structural features in the one or more cavities (block 1120).

[0093] In some cases, the structural features may be formed by injecting a suitable material such as polyimide, polycarbonate, polyester, or a combination thereof. In some cases, a secondary molding technique may be used. In some cases, the structural feature material may be partially embedded in the thermal barrier. In some cases, the structural feature material may be embedded in the thermal barrier so that it extends through it. In some cases, the method may also include heat pressing a portion of the structural feature material.

[0094] Various notes and examples

[0095] Embodiment 1 is a battery module comprising: a battery cell stack within a module housing; and a thermal barrier comprising aerogel between at least two cells in the battery cell stack, the thermal barrier comprising an isolation layer and structural features distributed in the isolation layer.

[0096] In embodiment 2, the subject matter of embodiment 1 optionally includes, wherein the structural feature penetrates the thickness of the isolation layer.

[0097] In Example 3, the subject matter of any one or more of Examples 1 to 2 optionally includes, wherein the structural feature includes a thickness, and the thickness is greater than a thickness of the thermal barrier.

[0098] In Example 4, the subject matter of any one or more of Examples 1 to 3 optionally includes, wherein the structural feature includes a thickness, and the thickness is substantially equal to the thickness of the thermal barrier.

[0099] In Example 5, the subject matter of any one or more of Examples 1 to 4 optionally includes, wherein the structural feature imparts shear forces to the thermal barrier relative to at least two adjacent cells.

[0100] In Example 6, the subject matter of any one or more of Examples 1 to 5 optionally includes, wherein the thermal barrier comprises a single layer.

[0101] In Example 7, the subject matter of any one or more of Examples 1 to 6 optionally includes, wherein the thermal barrier includes multiple layers.

[0102] In Example 8, the subject matter of any one or more of Examples 1 to 7 optionally includes, wherein the structural features reduce delamination of the thermal barrier.

[0103] In Example 9, the subject matter of any one or more of Examples 1 to 8 optionally includes, wherein the structural feature includes a plurality of rods.

[0104] In Example 10, the subject matter described in any one or more of Examples 1 to 9 optionally includes, wherein the structural feature includes a plurality of strips.

[0105] In Example 11, the subject matter described in any one or more of Examples 1 to 10 optionally includes, wherein the structural feature includes a plurality of points.

[0106] In Example 12, the subject matter of any one or more of Examples 1 to 11 optionally includes, wherein the structural features include a plurality of features at least partially embedded in the thermal barrier.

[0107] In Example 13, the subject matter of Example 12 optionally includes wherein each of the plurality of features extends through a thickness of the thermal barrier.

[0108] In Example 14, the subject matter of any one or more of Examples 12 to 13 optionally includes, wherein one end of each of the plurality of features extends outward from the thermal barrier.

[0109] In Example 15, the subject matter of any one or more of Examples 12 to 14 can optionally include, wherein an end of each of the plurality of features extends partially through the thermal barrier.

[0110] In Example 16, the subject matter of any one or more of Examples 12 to 15 can optionally include, wherein each of the plurality of features extends through a laminate thickness of the thermal barrier.

[0111] In Example 17, the subject matter of any one or more of Examples 1 to 16 optionally includes, wherein the structural feature includes a secondary molded material.

[0112] In Example 18, the subject matter of any one or more of Examples 1 to 17 optionally includes, wherein the structural feature includes a frame structure at least partially embedded in the thermal barrier.

[0113] In Example 19, the subject matter of any one or more of Examples 1 to 18 can optionally include, wherein the structural feature comprises a dual frame structure at least partially embedded in the thermal barrier.

[0114] In Example 20, the subject matter of any one or more of Examples 1 to 19 optionally includes, wherein the structural feature includes a sawtooth structure at least partially embedded in the thermal barrier.

[0115] In Example 21, the subject matter of Example 20 optionally includes, wherein the structural feature includes a double sawtooth structure at least partially embedded in the thermal barrier.

[0116] In Example 22, the subject matter of any one or more of Examples 20 to 21 optionally includes, wherein a portion of the serrations extend beyond a surface of the thermal barrier.

[0117] In Example 23, the subject matter of any one or more of Examples 20 to 22 optionally includes, wherein the sawtooth structural features provide compressibility along the thickness of the thermal barrier.

[0118] In Example 24, the subject matter of any one or more of Examples 1 to 23 optionally includes, wherein the structural features include flexible fibers.

[0119] In Example 25, the subject matter of Example 24 optionally includes wherein the flexible fibers are woven through the thermal barrier.

[0120] In Example 26, the subject matter of any one or more of Examples 1 to 25 optionally includes, wherein the structural feature is located within the thermal barrier at a non-zero angle relative to a surface of the thermal barrier.

[0121] In Example 27, the subject matter of any one or more of Examples 1 to 26 optionally includes, wherein the structural features are heat pressed into the thermal barrier.

[0122] In Example 28, the subject matter of any one or more of Examples 1 to 27 optionally includes, wherein the structural feature includes a connecting layer pressed onto the thermal barrier.

[0123] In Example 29, the subject matter of any one or more of Examples 1 to 28 optionally includes, wherein the structural feature includes a middle portion and one or more edges, each edge being thinner than the middle portion.

[0124] Embodiment 30 is a thermal barrier for use in a battery module, the thermal barrier comprising: an isolation layer comprising aerogel, the isolation layer being configured to thermally isolate individual battery cells within the battery module; and structural features distributed within the isolation layer.

[0125] In Example 31, the subject matter of Example 30 optionally includes, wherein the structural features include a plurality of features at least partially embedded in the thermal barrier.

[0126] In Example 32, the subject matter of Example 31 optionally includes, wherein the structural feature includes a plurality of rods.

[0127] In Example 33, the subject matter described in any one or more of Examples 30 to 32 optionally includes, wherein the structural feature includes a plurality of strips.

[0128] In Example 34, the subject matter described in any one or more of Examples 30 to 33 optionally includes, wherein the structural feature includes multiple points.

[0129] In Example 35, the subject matter of any one or more of Examples 30 to 34 optionally includes, wherein the structural feature comprises a secondary molded material.

[0130] In Example 36, the subject matter of Example 35 optionally includes, wherein the structural feature includes a frame structure at least partially embedded in the thermal barrier.

[0131] In Example 37, the subject matter of any one or more of Examples 35 to 36 optionally includes, wherein the structural feature includes a dual frame structure at least partially embedded in the thermal barrier.

[0132] In Example 38, the subject matter of any one or more of Examples 35 to 36 optionally includes, wherein the structural feature includes a sawtooth structure at least partially embedded in the thermal barrier.

[0133] In Example 39, the subject matter of any one or more of Examples 35 to 36 optionally includes, wherein the structural feature includes a double sawtooth structure at least partially embedded in the thermal barrier.

[0134] In Example 40, the subject matter of any one or more of Examples 30 to 39 optionally includes, wherein the structural features include flexible fibers.

[0135] In Example 41, the subject matter of any one or more of Examples 30 to 40 optionally includes, wherein the structural feature includes a connecting layer pressed onto the thermal barrier.

[0136] Embodiment 42 is a method of making a structural feature in a thermal barrier comprising an aerogel, the method comprising: removing a portion of the aerogel to form one or more cavities; and forming the structural feature in the one or more cavities.

[0137] In Example 43, the subject matter of Example 42 optionally includes, wherein forming the structural feature includes injecting a structural material into the one or more cavities.

[0138] In Example 44, the subject matter described in Example 43 optionally includes that the structural material comprises polyimide, polycarbonate, polyester or a combination thereof.

[0139] In Example 45, the subject matter of any one or more of Examples 42 to 44 optionally includes, wherein forming the structural features includes partially infusing the structural features into the thickness of the aerogel.

[0140] In Example 46, the subject matter of any one or more of Examples 42 to 45 optionally includes, wherein forming the structural features includes injecting the structural features through the thickness of the aerogel.

[0141] In Example 47, the subject matter of any one or more of Examples 42 to 46 optionally includes, wherein forming the structural features includes uniformly distributing the structural features within the aerogel.

[0142] In Example 48, the subject matter of any one or more of Examples 42 to 47 optionally includes, wherein forming the structural feature includes overmolding the structural material onto the aerogel.

[0143] In Example 49, the subject matter of any one or more of Examples 42 to 48 optionally includes forming the connecting layer by heat pressing the structural features.

[0144] Each of these non-limiting embodiments may stand alone or be combined with one or more of the other embodiments in various permutations or combinations.

[0145] The above detailed description includes reference to the drawings that form a part of the detailed description. The drawings show the specific embodiments in which the present invention can be practiced by way of illustration. These embodiments are also referred to as "embodiments" in this article. These embodiments may include elements other than the elements shown or described. However, the inventors also consider embodiments in which only those elements shown or described are provided. In addition, whether relative to the specific embodiments (or one or more aspects thereof) shown or described herein or relative to other embodiments (or one or more aspects thereof) shown or described herein, the inventors also consider embodiments using any combination or arrangement of the elements shown or described (or one or more aspects thereof).

[0146] In the event of an inconsistency in usage between this document and any document incorporated by reference, the usage in this document controls.

[0147] As is common in patent documents, in this document, the terms "a" or "an" are used to include one or more than one, independent of any other instances or uses of "at least one" or "one or more". Unless otherwise stated, in this document, the term "or" is used to refer to a non-exclusive or, such that "A or B" includes "is A but not B", "is B but not A", and "A and B". In this document, the terms "including" and "wherein" are used as simple equivalents of the terms "including" and "wherein". In addition, in the appended claims, the terms "including" and "comprising" are open-ended, that is, if the system, device, article, composition, formulation, or process in the claim includes other elements in addition to the elements listed after such terms, it is still deemed to fall within the scope of the claim. In addition, in the appended claims, the terms "first", "second", and "third" are used only as labels and are not intended to impose numerical requirements on their subject matter.

[0148] The method embodiments described herein may be implemented at least in part by a machine or computer. Some embodiments may include a computer-readable medium or a machine-readable medium, which is encoded with operable instructions to configure an electronic device to perform the method described in the above embodiments. The implementation of such methods may include code, such as microcode, assembly language code, high-level language code, etc. Such code may include computer-readable instructions for performing various methods. The code may form a part of a computer program product. In addition, in an embodiment, for example, during execution or at other times, the code may be tangibly stored on one or more volatile, non-temporary or non-volatile tangible computer-readable media. Examples of these tangible computer-readable media may include, but are not limited to, hard disks, removable disks, removable optical disks (e.g., optical disks and digital video disks), tapes, memory cards or memory sticks, random access memory (RAM), read-only memory (ROM), etc.

[0149] The above description is intended to be illustrative rather than restrictive. For example, the embodiments described above (or one or more aspects thereof) may be used in combination with each other. For example, after reading the above description, a person of ordinary skill in the art may use other embodiments. The abstract is provided to allow the reader to quickly determine the nature of the technical disclosure. It is understood at the time of submission that it will not be used to interpret or limit the scope or meaning of the claims. In addition, in the above specific embodiments, various features may be combined together to simplify the present disclosure. This should not be interpreted as meaning that the disclosed features that are not requested for protection are necessary for any claim. On the contrary, the creative subject matter may be in less than all the features of a specific disclosed embodiment. Therefore, the attached claims are hereby incorporated into the specific embodiments as embodiments or embodiments, each claim itself exists as a separate embodiment, and it is expected 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 attached claims and the scope of the full equivalents enjoyed by these claims.

Claims

1. A battery module, characterized in that: include: a stack of battery cells within a module housing; a thermal barrier between at least two cells in the battery cell stack, the thermal barrier comprising an insulating layer having a major plane; and A structural feature is distributed in the isolation layer, the structural feature comprising a plurality of elements, each of the plurality of elements extending at least partially through the major plane.

2. The battery module according to claim 1, wherein: The isolation layer includes aerogel.

3. The battery module according to claim 1, wherein: The isolation layer includes a second main plane on a side opposite to the first main plane.

4. The battery module according to claim 3, wherein: The isolation layer includes a thickness extending between the first major plane and the second major plane.

5. The battery module according to claim 4, wherein: The plurality of elements are embedded in the thickness.

6. The battery module according to claim 4, wherein: The plurality of elements extend beyond the thickness.

7. The battery module according to claim 1, wherein: The plurality of elements includes a rod.

8. The battery module according to claim 1, wherein: The plurality of elements includes a strip.

9. The battery module according to claim 1, wherein: The plurality of elements include points.

10. The battery module according to claim 1, wherein: The plurality of elements comprises a unitary structure.

11. The battery module according to claim 1, wherein: The structural features include a frame structure at least partially embedded in the thermal barrier.

12. The battery module according to claim 1, wherein: The structural features include a dual frame structure at least partially embedded in the thermal barrier.

13. The battery module according to claim 1, wherein: The structural feature includes a sawtooth structure at least partially embedded in the thermal barrier.

14. The battery module according to claim 13, wherein: The structural feature includes a double sawtooth structure at least partially embedded in the thermal barrier.

15. The battery module according to claim 13, wherein: A portion of the serrations extends beyond the surface of the thermal barrier.

16. The battery module according to claim 13, wherein: The sawtooth structural features provide compressibility along the thickness of the thermal barrier.

17. The battery module according to claim 1, wherein: The plurality of elements include flexible fibers.

18. The battery module according to claim 17, wherein: The flexible fibers are woven through the thermal barrier.

19. The battery module according to claim 1, wherein: The structural features are located within the thermal barrier at a non-zero angle relative to the major plane.

20. The battery module according to claim 1, wherein: The structural features are heat pressed into the thermal barrier along the major plane.

21. The battery module according to claim 1, wherein: The structural feature includes a connecting layer pressed onto the thermal barrier along the major plane.

22. The battery module according to claim 1, wherein: The structural feature includes a middle portion and one or more edges, each of the edges being thinner than the middle portion.

23. A thermal barrier for a battery module, characterized in that: The thermal barrier comprises: an isolation layer configured to thermally isolate individual battery cells within the battery module; and Structural features are distributed within the isolation layer.

24. The thermal barrier of claim 23, wherein: The isolation layer includes aerogel.

25. The thermal barrier of claim 23, wherein: The structural features include a plurality of features at least partially embedded in the thermal barrier.

26. The thermal barrier of claim 23, wherein: The structural features include a plurality of bars, strips or dots.

27. The thermal barrier of claim 23, wherein: The structural features include a frame structure at least partially embedded in the thermal barrier.

28. The thermal barrier of claim 23, wherein: The structural feature includes a sawtooth structure at least partially embedded in the thermal barrier.

29. The thermal barrier of claim 23, wherein: The structural features include flexible fibers.

30. The thermal barrier of claim 23, wherein: The structural feature includes a connecting layer pressed onto the thermal barrier.

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