Battery array with staggered vent design

Abstract

The present disclosure provides a battery array with a staggered vent design. A battery array for a traction battery pack is provided. An exemplary battery array may include: an inner component including a ventilation channel; and an outer member including a vent hole. The vent holes may be interleaved with respect to the vent channels to establish a tortuous vent path between the interior and exterior of the battery array.

Description

Technical Field

[0001] The present disclosure relates generally to traction battery packs, and more particularly to a battery array that provides a tortuous vent path for exhausting battery ventilation byproducts from an interior of the battery array. Background Art

[0002] An electrified vehicle includes a traction battery pack for powering the vehicle's electric motor and other electrical loads. The traction battery pack includes a plurality of battery cells and various other battery internal components that support electric vehicle propulsion. Summary of the invention

[0003] A battery array for a traction battery pack according to an exemplary aspect of the present disclosure includes, inter alia, an internal component including a ventilation passage; and an external component including ventilation holes that are staggered relative to the ventilation passage to establish a tortuous ventilation path between the interior and exterior of the battery array.

[0004] In another non-limiting embodiment of the foregoing battery array, the internal component is part of a battery cell sensing assembly.

[0005] In another non-limiting embodiment of any of the foregoing battery arrays, the internal component is a base frame of the battery cell sensing assembly.

[0006] In a further non-limiting embodiment of any of the foregoing battery arrays, a thermal barrier is secured to an underside of the base frame.

[0007] In another non-limiting embodiment of any of the foregoing battery arrays, the thermal barrier includes a second ventilation channel aligned with the ventilation channel.

[0008] In another non-limiting embodiment of any of the foregoing battery arrays, the external component is part of an array housing of the battery array.

[0009] In another non-limiting embodiment of any of the foregoing battery arrays, the external component is a top cover of the array housing.

[0010] In another non-limiting embodiment of any of the foregoing battery arrays, the internal component is positioned between the top cover and a plurality of battery cells of the battery array.

[0011] In another non-limiting embodiment of any of the foregoing battery arrays, a bridging tab of the outer member extends over a top of at least a portion of the ventilation channel of the inner member.

[0012] In another non-limiting embodiment of any of the foregoing battery arrays, the bridging tab is connected between the vent and a second vent of the exterior component.

[0013] According to another exemplary aspect of the present disclosure, a battery array for a traction battery pack includes, inter alia: an array housing; a plurality of battery cells, the plurality of battery cells being contained within the array housing; and a cell sensing assembly, the cell sensing assembly being positioned between the plurality of battery cells and a cover of the array housing. Ventilation holes formed through the cover are staggered relative to ventilation channels formed through a base frame of the cell sensing assembly.

[0014] In another non-limiting embodiment of the foregoing battery array, the cover is a top cover of the array housing.

[0015] In a further non-limiting embodiment of any of the foregoing battery arrays, a thermal barrier is secured to an underside of the base frame.

[0016] In a further non-limiting embodiment of any of the foregoing battery arrays, the thermal barrier includes a second ventilation channel.

[0017] In another non-limiting embodiment of any of the foregoing battery arrays, the second ventilation channel is aligned with the ventilation channel of the base frame.

[0018] In another non-limiting embodiment of any of the foregoing battery arrays, the ventilation holes are staggered relative to the ventilation channels to establish a tortuous ventilation path between the interior and exterior of the battery array.

[0019] In another non-limiting embodiment of any of the foregoing battery arrays, a bridging tab of the cover extends over a top of at least a portion of the ventilation channel of the base frame.

[0020] In another non-limiting embodiment of any of the foregoing battery arrays, the bridging tab is connected between the vent and a second vent of the cover.

[0021] In another non-limiting embodiment of any of the foregoing battery arrays, the cover is a top cover of the array housing.

[0022] In another non-limiting embodiment of any of the foregoing battery arrays, the plurality of battery cells are arranged into at least two cell stack subassemblies separated by a central wall.

[0023] The embodiments, examples and alternatives of the preceding paragraphs, claims or the following description and drawings (including any of their various aspects or corresponding individual features) may be adopted independently or in any combination. Features described in conjunction with one embodiment apply to all embodiments, unless such features are incompatible.

[0024] The various features and advantages of the present disclosure will become apparent to those skilled in the art from the following detailed description. The drawings that accompany the detailed description can be briefly described as follows. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 An electrified vehicle is schematically shown.

[0026] Figure 2 The battery array of the traction battery pack is shown. To show the internal components, Figure 2 The selected portion of the battery array is removed.

[0027] Figure 3 yes Figure 2 A partially exploded view of the battery array.

[0028] Figure 4 yes Figure 2 and Figure 3 Top view of a portion of a battery array.

[0029] Figure 5 It passes through Figure 4 Cross-sectional view of section 5-5. DETAILED DESCRIPTION

[0030] The present disclosure details a battery array for a traction battery pack. An exemplary battery array may include an interior component including a ventilation channel and an exterior component including ventilation holes. The ventilation holes may be staggered relative to the ventilation channel to establish a tortuous ventilation path between the interior and exterior of the battery array. These and other features are discussed in more detail in the following paragraphs of this detailed description.

[0031] Figure 1An electrified vehicle 10 is schematically shown. The electrified vehicle 10 may include any type of electrified powertrain. In one embodiment, the electrified vehicle 10 is a battery electric vehicle (BEV). However, the concepts described herein are not limited to BEVs and may be extended to other electrified vehicles, including but not limited to hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), fuel cell vehicles, etc. Therefore, although not specifically shown in the exemplary embodiment, the powertrain of the electrified vehicle 10 may be equipped with an internal combustion engine, which may be used alone or in combination with other power sources to propel the electrified vehicle 10.

[0032] In the illustrated embodiment, the electrified vehicle 10 is depicted as an automobile. However, the electrified vehicle 10 may alternatively be a sport utility vehicle (SUV), a van, a pickup truck, or any other vehicle configuration. Although specific component relationships are shown in the drawings of the present disclosure, the drawings are not intended to limit the present disclosure. The placement and orientation of the various components of the electrified vehicle 10 are shown schematically and may vary within the scope of the present disclosure. In addition, the various drawings attached to the present disclosure are not necessarily drawn to scale, and some features may be enlarged or minimized to emphasize certain details of a particular component or system.

[0033] In one embodiment, the electrified vehicle 10 is a pure electric vehicle that is propelled solely by electricity, such as by one or more electric machines 12, without any assistance from an internal combustion engine. The electric machines 12 can operate as electric motors, generators, or both. The electric machines 12 receive electricity and can convert the electricity into torque for driving one or more wheels 14 of the electrified vehicle 10.

[0034] Voltage bus 16 may electrically couple electric machine 12 to traction battery pack 18. Traction battery pack 18 is an exemplary electrified vehicle battery. Traction battery pack 18 may be a high voltage traction battery pack assembly that includes a plurality of battery cell groups capable of outputting electrical power to power electric machine 12 and / or other electrical loads of electrified vehicle 10. Other types of energy storage devices and / or output devices may alternatively or additionally be used to power electrified vehicle 10.

[0035] The traction battery pack 18 may be secured to an underbody 20 of the electrified vehicle 10 . However, the traction battery pack 18 may be located elsewhere on the electrified vehicle 10 within the scope of the present disclosure.

[0036] Figure 2 , Figure 3 , Figure 4 and Figure 5 A traction battery pack (e.g., such as Figure 1An exemplary battery array 22 of a traction battery pack 18). Figures 2 to 3 One or more battery arrays of similar design to the battery array 22 shown in may be packaged within the traction battery pack 18 .

[0037] The battery array 22 may include a plurality of battery cells 24 (see Figure 2 ). In one embodiment, the battery cells 24 are lithium-ion pouch cells. However, within the scope of the present disclosure, battery cells having other geometries (cylindrical, prismatic, etc.) and / or chemistries (nickel-metal hydride, lead acid, etc.) may alternatively be utilized. The total number of battery cells 24 disposed within the battery array 22 may vary and is not intended to limit the present disclosure.

[0038] The battery cells 24 may be grouped together in one or more cell stack subassemblies 26, each of which is arranged to extend along a respective stack axis A. In the illustrated embodiment, the battery array 22 includes two cell stack subassemblies 26 separated from each other by a center wall 28. However, within the scope of the present disclosure, a greater or lesser number of cell stack subassemblies 26 may be provided within the battery array 22. In one embodiment, the stack axis A is transverse to the longitudinal axis B of the battery array 22. However, other configurations are possible.

[0039] Each cell stack subassembly 26 may include a cell sensing assembly 30 . The cell sensing assembly 30 may include sense leads and other circuitry necessary to monitor voltage and temperature information associated with the battery cells 24 of each cell stack subassembly 26 of the battery array 22 .

[0040] Each cell sensing assembly 30 may include a base frame 32 and a thermal barrier 34. The thermal barrier 34 may be secured to or integrally formed with the underside of the base frame 32 and may be configured to protect the various circuits of the cell sensing assembly 30, such as from heat generated within the battery cells 24, for example. The thermal barrier 34 may be made of foam, mica, woven fabric, or any other high temperature resistant material within the scope of the present disclosure.

[0041] The cell stack subassembly 26 and various other internal components of the battery array 22 can be housed within the array housing 36. For example, the array housing 36 can be arranged to substantially surround each cell stack subassembly 26. The array housing 36 can include a plurality of plate members that can be arranged to provide a top cover 38, a bottom cover 40, a pair of side covers 42, and a pair of end covers 44 for the battery array 22. Two or more of the top cover 38, the bottom cover 40, the side covers 42, and the end covers 44 can be formed together as a single piece to reduce parts and complexity. For example, the bottom cover 40 and the end covers 44 can be formed together to establish a U-shaped structure that covers the ends and bottom of the battery array 22. However, other configurations are contemplated within the scope of the present disclosure.

[0042] Each cell sensing assembly 30 may be positioned between the array housing 36 and the battery cell 24. In one embodiment, each cell sensing assembly 30 is located between the top cover 38 and the upper surface of the battery cell 24. However, other configurations are possible within the scope of the present disclosure.

[0043] Although rare, the battery array 22 may experience a battery thermal event during its operation. A battery thermal event may occur, for example, during an overcharge condition, an over-discharge condition, or other condition, and may cause one or more of the battery cells 24 to emit battery ventilation byproducts, which may include gases, effluent particles, and / or other ventilation byproducts.

[0044] The battery array 22 may include features designed to manage / mitigate the effects of battery thermal events. For example, reference is now primarily made to Figure 3 , Figure 4 and Figure 5 , a first plurality of ventilation channels 46 may be formed through the base frame 32 of each cell sensing assembly 30. A second plurality of ventilation channels 48 may be formed through the thermal barrier 34 of each cell sensing assembly 30. The ventilation channels 48 may be directly aligned with the ventilation channels 46 to allow battery ventilation byproducts to pass through the cell sensing assembly 30 from the battery cell 24 experiencing a battery thermal event. It is worth noting that pre-formed or pre-cut ventilation channels may not be a necessary feature of the thermal barrier 34, such as when the thermal barrier 34 is made of a porous material (e.g., foam).

[0045] A plurality of vent holes 50 may be formed through the top cover 38 (or any other plate member) of the array housing 36. In the assembled state of the battery array 22, the vent holes 50 may be staggered relative to the vent channels 46 to form a tortuous vent path 52 between the interior I and the exterior E of the battery array 22 (see FIG. Figure 5). For example, when one or more of the battery cells 24 release battery ventilation byproducts during a battery thermal event, the battery ventilation byproducts may travel through one or more of the ventilation passages 46. However, before exiting through the vent holes 50, the battery ventilation byproducts must first change direction at least once to move axially around the bridging tabs 54 connected between adjacent vent holes 50 of the top cover 38, thereby slowing the velocity of the exiting gases.

[0046] Furthermore, the staggered relationship between the ventilation channels 46 and the ventilation holes 50 can prevent the entry of battery ventilation byproducts released by adjacent battery arrays and / or adjacent battery cell groups of the traction battery pack 18. For example, the bridging tabs 54 can at least partially block battery ventilation byproducts from adjacent battery arrays from entering the interior of the battery array 22, and the bridging tabs 54 can also at least partially block battery ventilation byproducts from adjacent battery cell groups from propagating to another battery cell group within the same battery array 22. Therefore, the proposed design can be further used to slow down inter-array and / or inter-cell group propagation during battery thermal events.

[0047] An exemplary battery array of the present disclosure includes a staggered ventilation design that provides a tortuous ventilation path for releasing battery ventilation byproducts from the array during a battery thermal event. The staggered design is used to both reduce the velocity of ventilation byproducts leaving the array and limit the entry of ventilation byproducts into the array from adjacent arrays.

[0048] Although different non-limiting embodiments are shown as having specific components or steps, the embodiments of the present disclosure are not limited to these specific combinations. Some components or features from any one of the non-limiting embodiments may be used in combination with features or components from any one of the other non-limiting embodiments.

[0049] It should be understood that like reference numerals identify corresponding or similar elements throughout the several drawings.It should be understood that although particular component arrangements are disclosed and shown in these exemplary embodiments, other arrangements may also benefit from the teachings of the present disclosure.

[0050] The foregoing description should be interpreted as illustrative and not in any limiting sense. It will be appreciated by those skilled in the art that certain modifications may occur within the scope of the present disclosure. For these reasons, the attached claims should be studied to determine the true scope and content of the present disclosure.

Claims

1. A battery array for a traction battery pack, comprising: an interior component, the interior component including a ventilation passage; as well as An external component includes ventilation holes that are staggered relative to the ventilation channels to establish a tortuous ventilation path between the interior and exterior of the battery array.

2. The battery array of claim 1, wherein the internal component is part of a battery cell sensing assembly.

3. The battery array of claim 2, wherein the internal component is a base frame of the battery cell sensing assembly.

4. The battery array of claim 3, comprising a heat barrier secured to an underside of the base frame. 5 . The battery array of claim 4 , wherein the heat barrier comprises a second ventilation channel aligned with the ventilation channel.

6. A battery array as claimed in any preceding claim, wherein the external component is part of an array housing of the battery array.

7. The battery array of claim 6, wherein the external component is a top cover of the array housing.

8. The battery array of claim 7, wherein the internal component is positioned between the top cover and a plurality of battery cells of the battery array.

9. A battery array as described in any preceding claim, wherein the bridging tab of the external component extends above the top of at least a portion of the ventilation channel of the internal component, and optionally, wherein the bridging tab is connected between the vent and a second vent of the external component.

10. A battery array for a traction battery pack, comprising: array housing; a plurality of battery cells, the plurality of battery cells being accommodated inside the array housing; as well as a cell sensing assembly, the cell sensing assembly being positioned between the plurality of battery cells and a cover of the array housing, The ventilation holes formed through the cover are staggered relative to the ventilation channels formed through the base frame of the battery cell sensing assembly.

11. The battery array of claim 10, wherein the cover is a top cover of the array housing.

12. A battery array as claimed in claim 10 or 11, comprising a thermal barrier secured to an underside of the base frame, and optionally wherein the thermal barrier comprises a second ventilation channel aligned with the ventilation channel of the base frame.

13. The battery array of any one of claims 10 to 12, wherein the ventilation holes are staggered relative to the ventilation channels to establish a tortuous ventilation path between the interior and exterior of the battery array.

14. A battery array as described in any one of claims 10 to 13, wherein the bridging tab of the cover extends above the top of at least a portion of the ventilation channel of the base frame, and optionally, wherein the bridging tab is connected between the vent and a second vent of the cover, and optionally, wherein the cover is a top cover of the array housing.

15. The battery array of any one of claims 10 to 14, wherein the plurality of battery cells are arranged into at least two cell stack subassemblies separated by a central wall.

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