Polymer-based traction battery enclosure and method of forming same

Abstract

The present disclosure provides a polymer-based traction battery enclosure and a method of forming the same. A battery assembly includes at least one housing structure thermoformed around a battery assembly of a battery pack. A method of encapsulating a battery assembly may include placing a sheet of material adjacent a battery assembly of a battery pack; and thermoforming the sheet of material around the battery assembly to provide a housing structure for the battery assembly.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 603,512, filed on November 28, 2023, and the U.S. Provisional Application is incorporated herein by reference. Technical Field

[0003] The present disclosure relates generally to housings for battery assemblies of battery packs, and more particularly to thermoformed housings and methods of forming the same. Background Art

[0004] An enclosure for a traction battery pack may include a tray and a cover. The tray may be secured to the cover via mechanical fasteners. The enclosure facilitates electrical isolation of the traction battery pack components, helps protect those components from environmental factors, and supports the traction battery. The enclosure is typically metal or a metal alloy. Summary of the invention

[0005] In some aspects, the technology described herein relates to a battery assembly that includes: at least one housing structure thermoformed around the battery assembly of a battery pack.

[0006] In some aspects, the technology described herein relates to a battery assembly, wherein the battery assembly includes: a plurality of battery cells.

[0007] In some aspects, the technology described herein relates to a battery assembly, wherein the battery assembly further includes: a plurality of bus bars; and at least one heat exchange plate.

[0008] In some aspects, the technology described herein relates to a battery assembly, wherein the battery assembly is a positive mold for the at least one housing structure.

[0009] In some aspects, the technology described herein relates to a battery assembly wherein the at least one housing structure is vacuum thermoformed around the battery assembly.

[0010] In some aspects, the technology described herein relates to a battery assembly wherein the at least one housing structure includes a first housing structure and a second housing structure that together enclose the battery assembly.

[0011] In some aspects, the technology described herein relates to a battery assembly wherein at least one electrical interface extends through the at least one housing structure to the battery assembly.

[0012] In some aspects, the technology described herein relates to a battery assembly in which a coolant inlet, a coolant outlet, or both extend through the at least one housing structure.

[0013] In some aspects, the technology described herein relates to a battery assembly, further comprising: the battery assembly and a structural support assembly configured to support the at least one housing structure thermoformed around the battery assembly.

[0014] In some aspects, the technology described herein relates to a battery assembly wherein the structural support assembly is configured to support the battery assembly and the at least one housing structure.

[0015] In some aspects, the technology described herein relates to a battery assembly in which the structural support assembly is configured to be secured to an underside of an electric vehicle.

[0016] In some aspects, the technology described herein relates to a battery assembly that includes a plurality of battery cells that are immersion cooled.

[0017] In some aspects, the technology described herein relates to a battery assembly wherein the at least one housing structure houses a coolant.

[0018] In some aspects, the technology described herein relates to a battery assembly wherein the at least one enclosure structure provides a fluid boundary for a fluid coolant.

[0019] In some aspects, the technology described herein relates to a battery assembly, wherein the battery pack is a battery pack for an electrified vehicle.

[0020] In some aspects, the technology described herein relates to a method of encapsulating a battery assembly, comprising: placing a sheet of material adjacent to a battery assembly of a battery pack; and thermoforming the sheet of material around the battery assembly to provide a housing structure for the battery assembly.

[0021] In some aspects, the technology described herein is directed to a method wherein the thermoforming comprises vacuum thermoforming.

[0022] In some aspects, the technology described herein is directed to a method further comprising: using the battery assembly as a full compression mold for the housing structure during the thermoforming.

[0023] In some aspects, the technology described herein relates to a method wherein the battery assembly includes a plurality of battery cells.

[0024] In some aspects, the technology described herein relates to a method in which the housing assembly and the battery assembly are configured to be supported by a structural support assembly secured to an underside of an electrified vehicle.

[0025] The embodiments, examples and alternatives of the preceding paragraphs, claims or the following description and drawings, including any of their various aspects or respective individual features, may be taken independently or in any combination. Features described in conjunction with one embodiment apply to all embodiments, unless such features are incompatible. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] According to the detailed description, various features and advantages of the disclosed examples will become apparent to those skilled in the art. The drawings attached to the detailed description can be briefly described as follows:

[0027] Figure 1A and Figure 1B An example of thermoforming a sheet of material is schematically shown.

[0028] Figure 2 Multiple polymer-based sheets and a battery assembly are shown.

[0029] Figure 3 A polymer-based sheet is shown after thermoforming the sheet into a housing enclosing a battery assembly according to an exemplary aspect of the present disclosure.

[0030] FIG. 4A to FIG. 4D Stages in a method of enclosing a battery assembly within a housing provided by a thermoformed sheet material are shown according to another exemplary aspect of the present disclosure.

[0031] Figure 5A and Figure 5B Stages in a method of enclosing a battery assembly within a housing provided by a thermoformed sheet material are shown according to yet another exemplary aspect of the present disclosure.

[0032] Fig. 6A and Figure 6B Stages in a method of enclosing a battery assembly within a housing provided by a thermoformed sheet are shown according to yet another exemplary aspect of the present disclosure.

[0033] Fig. 7A and Figure 7B Shows Fig. 6A and Figure 6B A variation of the embodiment of FIG. DETAILED DESCRIPTION

[0034] The present disclosure relates to a battery pack housing manufactured using a thermoforming process. The battery pack housing can be polymer-based. When compared to other housing types that are typically metal or metal alloys, the battery pack housing can have a reduced packaging footprint and overall weight.

[0035] refer to Figure 1A and Figure 1B, an example thermoforming process forms a polymer-based material sheet 10 into a desired geometric shape 14 by drawing a vacuum within the mold. While drawing the vacuum, the material sheet 10 can be formed over a full-pressure mold 22. This can be considered vacuum forming or vacuum molding. In other examples, the thermoforming process is an overmolding process.

[0036] The material sheet 10 can be placed near the full compression mold 22 and heated to soften the material sheet 10 before forming the material sheet 10 over the full compression mold 22. The material sheet 10 can be a polymer-based material such as polycarbonate (PC), polypropylene (PP), high-density polyethylene (HDPE), polyethylene terephthalate (PET), acrylonitrile butadiene styrene (ABS), or some combination of these materials. Another type of polymer-based material can be used in other examples.

[0037] refer to Figure 2 and Figure 3 , the example thermoforming process forms the material sheet 10A and the material sheet 10B around the battery assembly 26 to provide a thermoformed housing 28. After thermoforming the material sheet 10A and the material sheet 10B around the battery assembly 26, the material sheet 10A and the material sheet 10B are a housing structure that together encapsulates the battery assembly 26. The battery assembly 26 effectively acts as a full compression mold 22 ( Figure 1A and Figure 1B ).

[0038] In this example, the sheets of material 10A, 10B are polymer based.Although the thermoformed shell 28 is formed from two sheets of material 10A, 10B in this example, other shells may be formed using more than two sheets of material.

[0039] In this example, the sheets of material 10A and 10B are vacuum formed over the battery assembly 26 to provide a thermoformed enclosure 28 surrounding the battery assembly 26, as shown in FIG. Figure 3 As shown. Vacuum ducts or vents 30 can be used to draw a vacuum V between the material sheets 10A and 10B, which effectively shrink-wraps the battery assembly 26 with the material sheets 10A and 10B. In other examples, other thermoforming processes that do not draw a vacuum can be used to form the material sheets 10A and 10B into the thermoformed housing 28.

[0040] The example battery assembly 26 is a matrix of individual battery cells 32 arranged in an individual array and disposed on a heat exchange plate 34. The thermoformed housing 28 houses the battery assembly 26 and can closely follow the contours of the battery assembly 26 by maintaining no gaps or very small gaps between the thermoformed housing 28 and the components of the battery assembly 26.

[0041] Reference now FIG. 4A to FIG. 4D, another example thermoformed housing 36 can be positioned around a battery assembly 40 having a plurality of individual battery cells 42 arranged in an array and disposed on a heat exchange plate 46. The battery assembly 40 can also include an electrical connector 50, such as a bus bar, electrically connected to the battery cells 42. Sensors, such as temperature sensors and pressure sensors, can also be disposed adjacent to the battery cells 42 and incorporated into the battery assembly 40.

[0042] Within the battery assembly 40, the battery cells 42 may be combined to facilitate management of internal forces caused by expansion or other causes in one or more of the battery cells 42. The thermoformed housing 36 may be formed around the battery assembly 40 while providing a coolant interface 54 and an electrical interface 58 extending through the thermoformed housing 36. In this example, the battery assembly 40 is environmentally separated and hermetically sealed from areas outside of the thermoformed housing 36, except for the coolant interface 54 and the electrical interface 58. This may protect the battery assembly 40 from debris, among other things.

[0043] Reference now Figure 5A and Figure 5B , the thermoformed housing 36 housing the battery assembly 40 can be supported within the electrified vehicle using a structural support assembly 66. The structural support assembly 66 can be a metal or a metal alloy. As can be appreciated, the structural support assembly 66 utilizes less metal or metal alloy material than if the entire thermoformed housing 36 were made of metal.

[0044] The structural support assembly 66 can be mechanically fastened to the underside of the electrified vehicle to support the thermoformed housing 36 and the battery assembly 40 housed within the thermoformed housing 36. In addition to supporting the battery assembly 40, the structural support assembly 66 can also protect the battery assembly 40 and the thermoformed housing 36 from external loads caused by movement of the vehicle, contact with the ground, contact with debris, etc.

[0045] Now refer to the figure for reference Fig. 6A and Figure 6B , another exemplary embodiment may include a polymer-based thermoformed housing 70 that houses a battery assembly 74 and is supported by a support structure 78. The battery assembly 74 is immersion cooled. The thermoformed housing 70 may contain a fluid utilized when immersing the battery assembly 74. That is, the thermoformed housing 70 may serve as at least a portion of a fluid boundary for a fluid that circulates during immersion cooling. The coolant inlet 82 may extend through an area of ​​the thermoformed housing 70. The coolant outlet 86 may extend through another area of ​​the thermoformed housing 70.

[0046] Fig. 7A and Figure 7B Shows Fig. 6A and Figure 6B A variation of the embodiment of, or any other embodiment of the present disclosure. Fig. 7A and Figure 7B In a variation of the thermoformed housing 70, a serviceable electronics box 90 is coupled to the battery assembly 74 within the thermoformed housing 70. This box 90 may have a BEC, BECM, fuse, DCDC converter, or other such components. Electrical connections 94 between the battery assembly 74 and the box 90 may pass through the thermoformed housing 70 and connect to the components in the electronics box 90. These electrical connections 94 along with the coolant inlet 82 and coolant outlet 86 may be sealed to the housing 70.

[0047] Features of the disclosed examples include a battery pack housing formed from a polymer-based material formed from a thermoformed polymer-based sheet into the shape of the housing. The resulting thermoformed plastic housing can effectively hermetically seal a desired battery assembly. When the battery pack housing effectively shrink-wraps the contained battery assembly, the packaging size of the battery assembly and its housing can be reduced. In some examples, an immersion cooling fluid can pass through the battery assembly contained by the housing.

[0048] The foregoing description is illustrative rather than restrictive in nature. Changes and modifications to the disclosed examples may become apparent to those skilled in the art, and the changes and modifications do not necessarily depart from the essence of the present disclosure. Therefore, the scope of protection granted to the present disclosure can only be determined by studying the attached claims.

[0049] According to the present invention, a battery assembly is provided, which has: at least one housing structure, wherein the at least one housing structure is thermoformed around the battery assembly of a battery pack.

[0050] According to one embodiment, the battery assembly includes a plurality of battery cells.

[0051] According to one embodiment, the battery assembly further includes a plurality of bus bars and at least one heat exchange plate.

[0052] According to one embodiment, the battery assembly is a full compression mold for the at least one housing structure.

[0053] According to one embodiment, the at least one housing structure is vacuum thermoformed around the battery assembly.

[0054] According to one embodiment, the at least one housing structure includes a first housing structure and a second housing structure that together enclose the battery assembly.

[0055] According to one embodiment, at least one electrical interface extends through the at least one housing structure to the battery assembly.

[0056] According to one embodiment, the coolant inlet, the coolant outlet or both extend through the at least one housing structure.

[0057] According to one embodiment, the above invention is further characterized by: the battery assembly and the structural support assembly, the structural support assembly is configured to support the at least one housing structure thermoformed around the battery assembly.

[0058] According to one embodiment, the structural support assembly is configured to support the battery assembly and the at least one housing structure.

[0059] According to one embodiment, the structural support assembly is configured to be secured to an underside of an electric vehicle.

[0060] According to one embodiment, the battery assembly comprises a plurality of battery cells which are immersion cooled.

[0061] According to one embodiment, the at least one housing structure contains a coolant.

[0062] According to one embodiment, the at least one housing structure provides a fluid boundary for the fluid coolant.

[0063] According to one embodiment, the battery pack is a battery pack of an electric vehicle.

[0064] According to the present invention, a method of encapsulating a battery assembly includes: placing a material sheet adjacent to a battery assembly of a battery pack; and thermoforming the material sheet around the battery assembly to provide a housing structure for the battery assembly.

[0065] According to one embodiment, the thermoforming comprises vacuum thermoforming.

[0066] According to one embodiment, the above invention is further characterized by using the battery assembly as a full compression mold for the housing structure during the thermoforming.

[0067] According to one embodiment, the battery assembly includes a plurality of battery cells.

[0068] According to one embodiment, the housing assembly and the battery assembly are configured to be supported by a structural support assembly secured to an underside of the electrified vehicle.

Claims

1. A battery assembly comprising: At least one housing structure is thermoformed around a battery assembly of the battery pack.

2. The battery assembly of claim 1, wherein the battery assembly comprises a plurality of battery cells, a plurality of bus bars, at least one heat exchange plate, or some combination of these items, and optionally wherein the battery pack is a battery pack for an electrified vehicle.

3. The battery assembly of claim 1, wherein the battery assembly is a full compression mold for the at least one housing structure.

4. The battery assembly of claim 1, wherein the at least one housing structure is vacuum thermoformed around the battery assembly.

5. The battery assembly of claim 1, wherein the at least one housing structure comprises a first housing structure and a second housing structure that together enclose the battery assembly.

6. The battery assembly of claim 1 , wherein at least one electrical interface extends through the at least one housing structure to the battery assembly, and optionally wherein a coolant inlet, a coolant outlet, or both extend through the at least one housing structure.

7. The battery assembly according to claim 1, further comprising: The battery assembly and a structural support assembly configured to support the at least one housing structure thermoformed around the battery assembly.

8. The battery assembly of claim 7, wherein the structural support assembly is configured to support the battery assembly and the at least one housing structure, and optionally wherein the structural support assembly is configured to be secured to an underside of an electric vehicle.

9. The battery assembly of claim 1, wherein the battery assembly comprises a plurality of battery cells that are immersion cooled.

10. The battery assembly of claim 1, wherein the at least one housing structure houses a coolant.

11. The battery assembly of claim 1 , wherein the at least one enclosure structure provides a fluid boundary for a fluid coolant.

12. A method for encapsulating a battery assembly, comprising: The material sheet is placed adjacent to the battery assembly of the battery pack; as well as The sheet of material is thermoformed around the battery assembly to provide a housing structure for the battery assembly.

13. The method of claim 12, wherein the thermoforming comprises vacuum thermoforming.

14. The method of claim 12, further comprising: The battery assembly is used as a full compression mold for the housing structure during the thermoforming.

15. The method of claim 12, wherein the battery assembly includes a plurality of battery cells, and optionally wherein the housing assembly and the battery assembly are configured to be supported by a structural support assembly secured to an underside of an electrified vehicle.

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