Battery array endplate design

Abstract

Battery array endplate designs for use within a traction battery pack are disclosed. An exemplary battery array of a traction battery pack may include features that facilitate a battery array assembly process. These features include channels for receiving compression jigs, interlocking features (ribs, bumps, pins, etc.) for engaging corresponding features of the array housing, and angled walls for compressing an upper portion of the stack of cells during the cell array assembly process.

Description

Technical Field

[0001] This disclosure generally relates to traction battery packs for electric vehicles, and more specifically, to battery array endplate designs that facilitate the battery array assembly process. Background Technology

[0002] Electrified vehicles include a traction battery pack that powers the vehicle's motor and other electrical loads. The traction battery pack comprises multiple battery cells and various other internal battery components that support the propulsion of the electric vehicle. Summary of the Invention

[0003] A battery array for a traction battery pack according to an exemplary aspect of this disclosure particularly includes an array housing and a cell stack, the cell stack being housed within the array housing and comprising a plurality of battery cells disposed between a first end plate and a second end plate. Each of the first end plate and the second end plate includes a channel configured to receive a compression clamp.

[0004] In another non-limiting embodiment of the aforementioned battery array, the first end plate establishes an interface between the draft angle of the array housing wall and the cell stack.

[0005] In another non-limiting embodiment of any of the aforementioned battery arrays, the first end plate includes a first side that abuts the wall and a second side that abuts a first battery cell among the plurality of battery cells.

[0006] In another non-limiting embodiment of any of the aforementioned battery arrays, the first side includes a first profile, and the second side includes a different second profile.

[0007] In another non-limiting embodiment of any of the aforementioned battery arrays, the first profile is inclined or angled, and the different second profile is flat.

[0008] In another non-limiting embodiment of any of the aforementioned battery arrays, the channel is formed in the first side of the first end plate.

[0009] In another non-limiting embodiment of any of the aforementioned battery arrays, the first side includes a first angled surface and a second angled surface that converge at the top of the first side.

[0010] In another non-limiting embodiment of any of the aforementioned battery arrays, the channel spans the first angled surface and the second angled surface.

[0011] In another non-limiting embodiment of any of the aforementioned battery arrays, the first side includes a first interlocking feature configured to engage a second interlocking feature of the wall.

[0012] In another non-limiting embodiment of any of the aforementioned battery arrays, the first interlocking feature is a raised flange.

[0013] In another non-limiting embodiment of any of the aforementioned battery arrays, the first interlocking feature is a rib.

[0014] In another non-limiting embodiment of any of the aforementioned battery arrays, the first interlocking feature is a pit.

[0015] In another non-limiting embodiment of any of the aforementioned battery arrays, the first interlocking feature is a groove.

[0016] In another non-limiting embodiment of any of the aforementioned battery arrays, each of the first end plate and the second end plate includes a first interlocking feature configured to interlock with a second interlocking feature of the wall of the array housing.

[0017] In another non-limiting embodiment of any of the aforementioned battery arrays, the wall is part of the bottom cover of the array housing.

[0018] A method for assembling a battery array according to another exemplary aspect of this disclosure includes, in particular: positioning a compression clamp within a channel of an end plate of a cell stack; applying a compressive force to the end plate using the compression clamp, the compressive force being sufficient to compress the cell stack; positioning the cell stack within a bottom cover of an array housing; and positioning a top cover of the array housing above the cell stack.

[0019] In another non-limiting embodiment of the foregoing method, the method includes removing the compression clamp from the channel after positioning the cell stack within the bottom cover.

[0020] In another non-limiting embodiment of any of the foregoing methods, after the cell stack is positioned within the bottom cover, a first interlocking feature of the end plate engages a second interlocking feature of the array housing to prevent the cell stack from exiting the bottom cover.

[0021] In another non-limiting embodiment of any of the foregoing methods, positioning the top cover includes compressing the upper portion of the cell stack via contact between the inclined wall of the top cover and the angled surface of the end plate.

[0022] In another non-limiting embodiment of any of the foregoing methods, the channel is formed within the angled surface.

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

[0024] Various features and advantages of this disclosure will become apparent to those skilled in the art from the following detailed description. The accompanying drawings, which briefly describe the specific embodiments, are as follows. Attached Figure Description

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

[0026] Figure 2 This is a perspective view of an exemplary battery array of a traction battery pack.

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

[0028] Figure 4 Is it through Figure 2 The cross-sectional view of section 4-4.

[0029] Figure 5 yes Figure 4 An enlarged view of a selected portion of the battery array shown.

[0030] Figure 6 An exemplary endplate of the battery array is shown.

[0031] Figure 7 yes Figure 6 An enlarged view of a fixed portion of the end plate shown.

[0032] Figure 8 Another exemplary endplate is shown.

[0033] Figure 9 Another exemplary endplate is shown.

[0034] Figure 10 Another exemplary endplate is shown.

[0035] Figure 10A The interface between the end plate and the array housing is shown.

[0036] Figure 11 , Figure 12 , Figure 13 , Figure 14 and Figure 15An exemplary method for assembling a battery array for a traction battery pack is illustrated schematically. Detailed Implementation

[0037] This disclosure details a battery array endplate design used within a traction battery pack. An exemplary battery array of a traction battery pack may include features that facilitate the battery array assembly process. These features include channels for receiving compression clamps, interlocking features (ribs, protrusions, pins, etc.) for engaging corresponding features of the array housing, and angled walls for compressing the upper portion of the cell stack during the battery array assembly process. These and other features are discussed in more detail in the following paragraphs of this detailed description.

[0038] Figure 1 An electrified vehicle 10 is schematically illustrated. 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 can 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 exemplary embodiments, 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.

[0039] In the illustrated embodiment, the electrified vehicle 10 is depicted as an automobile. However, the electrified vehicle 10 may alternatively be a sports utility vehicle (SUV), van, pickup truck, or any other vehicle configuration. Although specific component relationships are shown in the accompanying drawings of this disclosure, the illustrations are not intended to limit the scope of this disclosure. The placement and orientation of the various components of the electrified vehicle 10 are schematically shown and may vary within the scope of this disclosure. Furthermore, the various drawings accompanying this disclosure are not necessarily drawn to scale, and some features may be enlarged or minimized to emphasize certain details of particular components or systems.

[0040] In the illustrated embodiment, the electrified vehicle 10 is a purely electric vehicle propelled solely by electricity (such as by one or more motors 12) without the assistance of an internal combustion engine. The motor 12 may operate as an electric motor, a generator, or both. The motor 12 receives electricity and may convert the electricity into torque for driving one or more wheels 14 of the electrified vehicle 10.

[0041] Voltage bus 16 can electrically connect motor 12 to traction battery pack 18. Traction battery pack 18 is an exemplary electric vehicle battery. Traction battery pack 18 can be a high-voltage traction battery pack assembly including multiple battery cells capable of outputting power to supply motor 12 and / or other electrical loads of electric vehicle 10. Other types of energy storage devices and / or output devices may alternatively or additionally be used to supply power to electric vehicle 10.

[0042] The traction battery pack 18 can be fixed to the bottom 20 of the electric vehicle 10. However, within the scope of this disclosure, the traction battery pack 18 can be located elsewhere on the electric vehicle 10.

[0043] The traction battery pack 18 may include one or more battery arrays 22 (e.g., battery modules, assemblies, or groups of rechargeable battery cells 24) capable of outputting power to supply the motor 12 and / or other electrical loads of the electrified vehicle 10. Each of the one or more battery arrays 22 of the traction battery pack 18 may each include a plurality of battery cells 24 that store energy for supplying power to the various electrical loads of the electrified vehicle 10. Within the scope of this disclosure, the traction battery pack 18 may employ any number of battery arrays 22 and battery cells 24. Therefore, this disclosure should not be limited to... Figure 1 The height is shown as a schematic configuration.

[0044] In one embodiment, the battery cell 24 of each battery array 22 is a lithium-ion pouch cell. However, battery cells having other geometries (cylindrical, prismatic, etc.), other chemical substances (nickel-metal hydride, lead-acid, etc.), or both may be used alternatively within the scope of this disclosure.

[0045] Battery array 22 and various other battery internal components (e.g., bus electrical hub, battery electrical control module, wiring, connectors, etc.) can be housed within internal region 26 of housing assembly 28. Housing assembly 28 may include, for example, a housing cover and a housing tray. The housing cover may be secured (e.g., bolted, welded, glued, etc.) to the housing tray to provide internal region 26. The size, shape, and overall configuration of housing assembly 28 are not intended to limit this disclosure.

[0046] Figures 2 to 5 A battery array 22 for a traction battery pack is shown. For example, Figure 1 The traction battery pack 18 of the electrified vehicle 10 may include a battery pack having substantially similar characteristics to... Figures 2 to 5 The design of the battery array 22 shown is one or more battery arrays.

[0047] The battery array 22 may include one or more cell stacks 30 housed within an array housing 32. The array housing 32 may include a top cover 34 and a bottom cover 36. The top cover 34 may be vertically positioned above the bottom cover 36. Various terms such as “above,” “below,” “top,” and “bottom” are used in the various figures relative to the arrangement of components of the traction battery pack 18 and should not be considered limiting in any other way. These terms are for reference only when the traction battery pack 18 is installed... Figure 1 The general orientation of the electric vehicle 10. For the purposes of this disclosure, verticality is also referenced to the ground and how the traction battery pack 18 is oriented when mounted on the electric vehicle 10.

[0048] The top cover 34 can be secured (e.g., bolted, welded, adhered, etc.) to the bottom cover 36 to provide a sealed housing for receiving the cell stack 30. Within the scope of this disclosure, the size, shape, and configuration of the array housing 32 can vary.

[0049] The cell stack 30 may include a plurality of individual battery cells 24 arranged together along the cell stack axis A between opposing end plates 38. Although a single cell stack 30 having a specific number of battery cells 24 is shown in the accompanying drawings of this disclosure, the battery array 22 may include any number of cell stacks 30, each cell stack 30 having any number of individual battery cells 24.

[0050] The thermal energy level of the battery cells 24 in the battery array 22 can increase as the electrified vehicle 10 operates. A thermal management system can be used to manage the thermal energy level of the battery cells 24 in the battery array 22. The thermal management system can be configured to guide coolant C through the battery array 22 in order to manage the thermal energy within the battery array 22 by, for example, absorbing heat from the battery cells 24 of the battery pack 30 using coolant C.

[0051] In one embodiment, the thermal management system is an immersion thermal management system, wherein a portion of the cell stack 30 (here, at least a portion of the battery cells 24) may be immersed in a coolant C. Thermal energy can be transferred between the coolant C and the battery cells 24 as the coolant C flows above and / or around the battery cells 24 within the array housing 32. The coolant C helps manage the thermal levels of the battery cells 24 and other components of the battery array 22.

[0052] The thermal management system can deliver coolant C to the interior region of the battery array 22 through inlet 40 of array housing 32. Coolant C can fill one or more open areas inside the battery array 22, such that the battery cells 24 are immersed in and in direct contact with the coolant C. Coolant C can absorb heat from the battery cells 24 to manage thermal levels. Coolant C can exit the battery array 22 through outlet 42 of array housing 32. In one embodiment, both inlet 40 and outlet 42 are formed through the bottom cover 36 of array housing 32. However, other inlet 40 and / or outlet 42 locations are contemplated within the scope of this disclosure.

[0053] Coolant C exiting through outlet 42 can move to a heat exchange device (not shown), such as a heat exchanger, where heat can be transferred from coolant C to the atmosphere. A pump (not shown) can be operated to selectively circulate coolant C between battery array 22 and the heat exchange device, and then back to battery array 22.

[0054] The coolant C circulating in the immersion thermal management system can be a dielectric fluid designed for immersion cooling of the battery cell 24 or another type of non-conductive fluid (e.g., oil). However, other non-conductive fluids may also be suitable, and the actual chemical composition and design characteristics (e.g., dielectric constant, maximum breakdown strength, boiling point, etc.) may vary depending on the environment in which the battery array 22 is employed.

[0055] In another embodiment, the thermal management system is a conventional cold plate system, wherein a coolant C (such as ethylene glycol) circulates through a cold plate (not shown) to thermally manage the heat generated by the battery cell 24. Therefore, the teachings of this disclosure are not limited to battery arrays having an immersion thermal management system. In a cold plate type thermal management system, the battery cell 24 is not immersed in the coolant C.

[0056] One or more walls 44 of the array housing 32 may include draft angles α (see Figure 5 Therefore, the outline of all the battery cells 24 neatly accommodating the cell stack 30 may not be visible. Wall 44 may be part of a bottom cover 36, a top cover 34, or both. In one embodiment, the draft angle α is between about 3 degrees and about 5 degrees and may be the result of the casting process used to form the top cover 34 and bottom cover 36 of the array housing 32. However, the actual draft angle α can vary depending on design requirements and based on the type of manufacturing process used to form the array housing 32, as well as other design criteria.

[0057] Each end plate 38 can establish an interface that allows the draft angle α of the wall 44 of the array housing 32 to be converted or "corrected to a right angle" relative to the cell stack 30. Therefore, the end plates 38 fill the gap between the opposite ends of the cell stack 30 and the array housing 32, and can uniformly transfer the battery cell expansion force from the cell stack 30 to the array housing 32.

[0058] In one embodiment, the cross-sectional shape of each end plate 38 is substantially triangular. However, other cross-sectional shapes are conceivable within the scope of this disclosure. In this disclosure, the term "substantially" means that it is not necessary to precisely achieve the listed characteristics, parameters, or values, but rather that deviations or variations (including, for example, tolerances, hysteresis, measurement errors, measurement accuracy limitations, etc.) known to those skilled in the art may occur in amounts that do not preclude the effects the characteristics are intended to provide.

[0059] Continue to refer to Figures 2 to 4 In this case, Figures 5 to 7 Additional details associated with the end plates 38 of the cell stack 30 are shown. As further described below, in addition to providing the aforementioned cell stack-array housing interface, each end plate 38 may also include features designed to facilitate the battery array assembly process.

[0060] Each end plate 38 may include a first side 46 and a second side 48 located on the side of the end plate 38 opposite to the first side 46. In the assembled state of the battery array 22, the first side 46 of the end plate 38 faces and docks with the array housing 32, and the second side 48 faces and docks with one of the battery cells 24 located in the longitudinal range of the cell stack 30.

[0061] The first side surface 46 may include a first profile, and the second side surface 48 may include a different second profile. The first profile of the first side surface 46 may be configured to at least partially match the profile of the draft angle α of the wall 44 of the array housing 32, and the second profile of the second side surface 48 may be configured to match the profile of a main side surface of one of the battery cells 24 of the cell stack 30. Thus, in an exemplary embodiment, the first side surface 46 includes an inclined or angled profile, and the second side surface 48 includes a substantially flat profile.

[0062] The first side surface 46 of the end plate 38 may include a first angled surface 50 and a second angled surface 52. The first angled surface 50 and the second angled surface 52 may converge at a top point 54 of the first side surface 46. The top point 54 may be located at or near the midpoint of the first side surface 46 (e.g., along a vertical axis or Z-axis). In one embodiment, the first angled surface 50 may be angled to match the profile of the draft angle α of the wall 44 of the top cover 34, and the second angled surface 52 may be angled to match the profile of the draft angle α of the wall 44 of the bottom cover 36.

[0063] End plate 38 may include features that facilitate an interlocking connection between the cell stack 30 and the array housing 32. For example, a first side 46 of end plate 38 may include one or more first interlocking features 56 configured to interlock with a second interlocking feature 58 provided by the wall 44 of the bottom cover 36 of the array housing 32. The first interlocking feature 56 may engage the second interlocking feature 58 to maintain the Z-axis position of the cell stack 30 during and after mounting the cell stack 30 within the bottom cover 36 of the array housing 32.

[0064] In one embodiment, the first interlocking feature 56 is configured as a raised flange projecting outward from a second angled surface 52 of a first side surface 46 of the end plate 38, and the second interlocking feature 58 is configured as a recess formed in the wall 44 of the bottom cover 36 (see example...). Figures 5 to 7 In another embodiment, the first interlocking feature 56 is configured as a raised rib projecting outward from a second angled surface 52 of a first side surface 46 of the end plate 38 (see, for example...). Figure 8 In another embodiment, the first interlocking feature 56 is configured as a recess projecting outward from a second angled surface 52 of a first side surface 46 of the end plate 38 (see, for example...). Figure 9 In yet another embodiment, the first interlocking feature 56 is configured as a recess (e.g., see...). Figure 10 The groove protrudes inward from the second angled surface 52 of the first side surface 46 of the end plate 38 and is sized to receive a second interlocking feature 58 of a protruding flange or rib configured as an array housing 32 (see, for example, see...). Figure 10A Therefore, the first interlocking feature 56 can provide a convex or concave portion for the interlocking connection between the end plate 38 and the array housing 32. It is worth noting that the size, shape, position, and number of each of the first interlocking feature 56 and the second interlocking feature 58 can depend on the design requirements of the battery array assembly and other factors. Other embodiments may include... Figures 5 to 10 Any combination of the interlocking features shown.

[0065] The end plate 38 may additionally include features for receiving a compression tooling fixture or clamp for the compressor, which may be used to compress the cell stack along the cell stack axis A before inserting the cell stack 30 into the bottom cover 36 of the array housing 32, such as during a battery array assembly process. For example, as Figure 6 As best shown, the first side 46 of the end plate 38 may include one or more channels 60, the dimensions of which are designed to receive the compression clamps of the compressor. Each channel 60 may extend along the Z-axis of the end plate 38 and may extend across the entire height of the end plate 38.

[0066] In some embodiments, each channel 60 may separate adjacent first interlocking features 56 of the end plate 38 from each other along the width of the first side 46. In one embodiment, the channel 60 extends along an axis transverse to the axis of the first interlocking feature 56. However, other configurations are contemplated within the scope of this disclosure. It is worth noting that the size, shape, location, and number of channels 60 provided by the end plate 38 may depend on the design requirements of the battery array assembly and other factors.

[0067] In one embodiment, end plate 38 is a polymer-based component. In another embodiment, end plate 38 is a metal-based component. End plate 38 can be formed using any manufacturing technique.

[0068] Continue to refer to Figures 1 to 10 In this case, Figures 11 to 15 The method for assembling the aforementioned battery array 22 is illustrated schematically. First, as... Figure 11 As shown, the compression clamp 62 can be positioned to engage each channel 60 of each end plate 38 of the cell stack 30. Within the scope of this disclosure, the compression clamp 62 can be connected to a common compressor (not shown) or different compressors. Although for simplicity... Figure 11 Only a single end plate 38 is shown, but it should be understood that each channel 60 of the opposite end plate 38 of the cell stack 30 can be engaged simultaneously using an additional compression clamp 62.

[0069] Next, as Figure 12 As shown, the compression clamp 62 can be moved to compress the battery cell 24 along the cell stack axis A of the cell stack 30. For example, the pneumatic actuator of the compressor can drive the compression clamp 62, which is positioned on opposite ends of the cell stack 30, toward each other to apply a compressive force F to each opposite end plate 38. c This compresses the battery cell 24 along the cell stack axis A. The compressive force F C Essentially, the cell stack 30 is squeezed, thereby compressing the battery cell 24 and thus the cell stack 30 to a reduced thickness.

[0070] Maintaining the compressive force F applied at each opposite end plate 38 C Simultaneously, the cell stack 30 can be inserted into the bottom cover 36 of the array housing 32 (see...). Figure 13 Then the compression clamp 62 can be removed from channel 60 (see...). Figure 14 When the compression clamp 62 is removed, the cell stack 30 may expand slightly outward (e.g., along the...). Figure 14 (in the direction of arrow 99), thus allowing the first interlock feature 56 of the end plate 38 to engage the second interlock feature 58 of the bottom cover 36 and substantially preventing the cell stack 30 from exiting the bottom cover 36 along the Z-axis.

[0071] Finally, as Figure 15 As shown, the top cover 34 can be mounted above the cell stack 30. When the top cover 34 is mounted, the first angled surface 50 of the first side surface 46 of each end plate 38 can interact with the draft angle α of the wall 44 of the top cover 34. Therefore, when the top cover 34 is mounted, such as via a downward force F... D As the device moves further toward the bottom cover 36, the contact between the angled wall 44 of the top cover 34 and the first angled surface 50 (schematically shown at reference numeral 64) can partially recompress the upper portion of the cell stack 30 to the extent that some cell expansion occurs after the removal of the compression clamp 62. The top cover 34 can be secured to the bottom cover 36 in any manner to seal the array housing 32 around the cell stack 30.

[0072] The exemplary battery array disclosed herein includes an end plate having novel features for facilitating the battery array assembly process. For example, the end plate may include channels for receiving compression clamps, interlocking features (ribs, protrusions, pins, etc.) for engaging corresponding features of the array housing, and angled walls for compressing the upper portion of the cell stack during the battery array assembly process.

[0073] While different non-limiting embodiments are shown having specific components or steps, the embodiments disclosed herein are not limited to those particular combinations. Some of the components or features from any of the non-limiting embodiments may be used in combination with features or components from any of the other non-limiting embodiments.

[0074] It should be understood that the same reference numerals identify corresponding or similar elements throughout all the figures. It should be understood that although particular arrangements of components are disclosed and shown in these exemplary embodiments, other arrangements may also benefit from the teachings of this disclosure.

[0075] The foregoing description should be interpreted as illustrative and not restrictive. Those skilled in the art will understand that certain modifications may be made within the scope of this disclosure. For these reasons, the appended claims should be examined to determine the true scope and content of this disclosure.

Claims

1. A battery array for a traction battery pack, comprising: Array housing; as well as A cell stack, the cell stack being housed within the array housing and comprising a plurality of battery cells disposed between a first end plate and a second end plate. Each of the first end plate and the second end plate includes a channel configured to receive a compression clamp.

2. The battery array according to claim 1, wherein the first end plate establishes an interface between the draft angle of the wall of the array housing and the cell stack.

3. The battery array according to claim 2, wherein the first end plate includes a first side surface abutting the wall and a second side surface abutting a first battery cell among the plurality of battery cells.

4. The battery array of claim 3, wherein the first side comprises a first profile, and the second side comprises a different second profile, and optionally, wherein the first profile is inclined or angled and the different second profile is flat.

5. The battery array of claim 3, wherein the channel is formed in the first side of the first end plate.

6. The battery array of claim 3, wherein the first side comprises a first angled surface and a second angled surface converging at the top of the first side, and optionally, wherein the channel spans the first angled surface and the second angled surface.

7. The battery array of claim 3, wherein the first side includes a first interlocking feature configured to engage a second interlocking feature of the wall.

8. The battery array according to claim 7, wherein the first interlocking feature is a raised flange or rib.

9. The battery array according to claim 7, wherein the first interlocking feature is a pit.

10. The battery array of claim 7, wherein the first interlocking feature is a groove.

11. The battery array according to any of the preceding claims, wherein each of the first end plate and the second end plate includes a first interlocking feature configured to interlock with a second interlocking feature of a wall of the array housing, and optionally, wherein the wall is part of a bottom cover of the array housing.

12. A method for assembling a battery array, comprising: Position the compression clamp within the channel of the end plate of the cell stack; The compression clamp is used to apply a compressive force to the end plate, and the compressive force is sufficient to compress the battery cell stack. Position the battery cell stack within the bottom cover of the array housing; and The top cover of the array housing is positioned above the cell stack.

13. The method of claim 12, further comprising, after positioning the cell stack within the bottom cover: Remove the compression clamp from the channel.

14. The method according to claim 12 or 13, wherein after the cell stack is positioned within the bottom cover, a first interlocking feature of the end plate engages a second interlocking feature of the array housing to prevent the cell stack from exiting the bottom cover.

15. The method according to any one of claims 12 to 14, wherein positioning the top cover comprises: The upper portion of the cell stack is compressed through contact between the inclined wall of the top cover and the angled surface of the end plate, and optionally, the channel is formed within the angled surface.

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