Support structure for angled battery cell design for a traction battery assembly

Abstract

Support structure (300) for a battery cell assembly (160), comprising: a pair of end plates (164) having a triangular prism shape, having opposing parallel inner surfaces (312) configured to exert a compressive force on battery cells (162) placed therebetween, and parallel outer surfaces (314) that are not parallel to the inner surfaces (312); and a pair of opposing support beams (306, 308) extending between the end plates (164), the end plates (164) and the beams (306, 308) being arranged that the outer surfaces (314) and the supports (306, 308) define a rectangular prism; characterized in that each of the support brackets (306, 308) defines a support feature having a first portion attached to respective inner corners (322) of the end plates (164), a second portion having a spacer guide (332) for receiving and orienting a corner portion of a cell spacer (330) such that the spacer (330) is parallel to the inner surfaces (312), and a third portion having a cell guide (336) for receiving and orienting a corner portion of a battery cell (162) such that the cell (162) is parallel to the inner surfaces (312).

Description

FIELD OF TECHNOLOGY

[0001] This disclosure relates to thermal management systems and battery cell designs for high-voltage batteries used in vehicles. GENERAL STATE OF THE ART

[0002] Vehicles such as battery electric vehicles (BEVs), plug-in hybrid electric vehicles (PHEVs), mild hybrid electric vehicles (MHEVs), or full hybrid electric vehicles (FHEVs) contain a power source, such as a high-voltage (HV) battery, that serves as the vehicle's propulsion source. The HV battery may include components and systems that support the control of the vehicle's performance and operation. The HV battery may include one or more arrays of battery cells electrically interconnected between battery cell terminals and interconnection busbars. The HV battery and the surrounding environment may include a thermal management system to support the control of the temperature of the HV battery's components, systems, and individual battery cells.

[0003] The document US 2013 / 0 149 591 A1 discloses a secondary battery module comprising a plurality of battery cells arranged in one direction, and a pair of end plates contacting the outermost surfaces of the plurality of battery cells, each of the two end plates comprising an inclined plane.

[0004] Document CN 2 02 022 113 U discloses a container body of a lithium battery for an electric vehicle, which container body comprises an outer casing, side walls and an upper casing, and which is provided with an inner chamber in which the battery monomers are arranged angularly next to one another, a support shoe and a fixing block being attached to the left and right sides of the inner chamber, respectively. BRIEF DESCRIPTION OF THE INVENTION

[0005] A support structure for a battery cell assembly includes a pair of end plates having a triangular prism shape, opposing parallel inner surfaces configured to exert a compressive force on battery cells placed therebetween, and parallel outer surfaces that are not parallel to the inner surfaces. The support structure also includes a pair of opposing support beams extending between the end plates. The end plates and beams are configured such that the outer surfaces and the beams define a rectangular prism. The inner surfaces may be oriented at an acute angle relative to at least one of the beams, and the acute angle may have a displacement angle value.The displacement angle value may be based on a surface friction coefficient of a battery tray configured to support the battery cells and an amount of compressive force exerted by the end plates on a plurality of cells sandwiched therebetween and supported by the battery tray. Each support tray may define a support feature including a first portion attached to the respective inside corner, a second portion having a spacer guide for receiving and orienting a corner portion of a cell spacer such that the spacer is parallel to the inside surfaces, and a third portion having a cell guide for receiving and orienting a corner portion of a battery cell such that the cell is parallel to the inside surfaces. Each support tray may further define a plurality of alternating first and second guides between the opposing inside corners.A plurality of cell spacers may be interposed between the end plates and may have corners oriented by the first guides such that the spacers are parallel to the inner surfaces. The cell spacers may define a plurality of ribs spaced at vertical intervals and extending outwardly on both sides of the spacer. The support structure may also include a thermal plate interposed beneath a battery cell region between the end plates and a plurality of cell spacers. The plurality of cell spacers may be interposed between the end plates and may have upper corners held by the first guides and lower corners in at least partial contact with the thermal plate and oriented such that the spacers are parallel to the inner surfaces.

[0006] A support structure for a battery cell assembly includes a pair of wedge-shaped end plates, each having inner corners, and a pair of support beams extending between the inner corners. The end plates and the beams are configured such that the end plates exert a compressive force on battery cells placed therebetween in a direction other than a direction defined by the beams. The end plates may further each have outer surfaces that are parallel to each other, inner surfaces that are parallel to each other and oriented at an acute angle relative to the respective outer surfaces, at least one side surface that extends between the outer and inner surfaces, and top surfaces. The inner corners may each be defined by an intersection of each of the inner surface, the top surface, and the side surface.The supports may each define a plurality of first guides sized to receive and orient a portion of a corner of a cell spacer such that the spacer is parallel to the inner surfaces. The supports may each further define a plurality of second guides sized to receive and orient a portion of a corner of a battery cell such that the battery cell is parallel to the inner surfaces. A pair of outer spacers may each be adjacent to the respective inner surfaces, oriented parallel to the inner surfaces, and at least partially disposed within four of the first guides adjacent the inner corners of the end plates.A plurality of inner spacers may be spaced at intervals between the pair of outer spacers, oriented parallel to the inner surfaces, and disposed at least partially within the other of the first guides between the four of the first guides adjacent to the inner corners. The end plates and the support beams may be configured to support and orient a plurality of battery cells therebetween such that the plurality of battery cells are parallel to the inner surfaces. The end plates may each define an inner surface oriented at an angle relative to the support beams equal to a displacement angle value dictated by a surface friction coefficient of a battery beam configured to support the battery cells and an amount of compressive force.The support brackets may each define a plurality of first guides sized to receive a portion of a plurality of corners of cell spacers such that the spacer is oriented at the angle and such that passages defined between the cell spacers provide a path for airflow.

[0007] A traction battery assembly includes a pair of end plates having a triangular prism shape, a pair of upper rails, and a plurality of cell spacers. The pair of upper rails extends between each of the end plates and defines a plurality of first guides sized to receive a portion of an upper corner of a spacer. The plurality of cell spacers are interposed between the end plates and arranged diagonally such that the spacers are oriented at an acute angle relative to the upper rails and such that at least a portion of the upper corners of the spacers are retained by the first guides.The pair of upper rails may each further define a plurality of second guides sized to receive a portion of an upper corner of a battery cell such that a front surface of the battery cell is oriented parallel to a front surface of the cell spacers. The cell spacers may be configured to define a plurality of airflow passages therebetween and may be diagonally oriented relative to the upper rails. A pair of lower rails may extend between each of the end plates and may define a plurality of shingle moldings sized to receive a portion of a lower corner of a battery cell. A pair of lower rails may extend between each of the end plates and may define a plurality of shingle moldings sized to receive a portion of a lower corner of a spacer.The acute angle may have a displacement angle value based on a surface friction coefficient of a battery tray supporting the assembly and an amount of compressive force exerted by the end plates on a plurality of cells interposed therebetween and supported by the battery tray. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a schematic diagram of a battery electric vehicle. Fig. 2 is a perspective view of a portion of a thermal management system for the traction battery of the vehicle in Fig. 1. Fig. 3A is a perspective view of a portion of a traction battery assembly with an air thermal management system. Fig. 3B is a perspective view of a battery cell from the traction battery assembly portion of Fig. 3A. Fig. 4A is a perspective view of a portion of another traction battery assembly that may include an air thermal management system. Fig. 4B is a perspective view of a battery cell from the traction battery assembly portion of Fig. 4A. Fig. 4C is an exemplary plan view of a portion of the traction battery assembly of Fig. 4A, which shows examples of airflow paths. Fig. Figure 4D is a plan view of a portion of another traction battery assembly that may include a liquid thermal management system. Fig. 5 is a perspective view of a portion of a support structure for the traction battery assembly portion of Fig. 4A. Fig. 6A is a perspective view of an end plate of the support structure of Fig. 5. Fig. Figure 6B is a perspective view of another end plate of the support structure of Fig. 5. Fig. 6C is an exemplary plan view of the supporting structure of Fig. 5, which shows examples of angles of orientation for sections of the end plates of the Fig. 6A and Fig. 6B shows. Fig. Figure 7A is a perspective view of a portion of an upper support beam of the support structure of Fig. 5. Fig. Figure 7B is a detailed perspective view of a portion of the upper support bracket of Fig. 7A. Fig. Figure 8 is a perspective view of a cell spacer that can be used with an air thermal management system, which is shown as being formed by portions of the support structure of Fig. 5 is shown held. Fig. Figure 9 is a perspective view of another cell spacer that can be used with a fluid thermal management system, which is shown as being formed by portions of the support structure of Fig. 5 is shown held. Fig. 10 is a detailed perspective view of a portion of the traction battery assembly of Fig. 4A, which shows areas of battery cell assemblies that may require additional support structure due to feathering of the battery cells. Fig. 11 is an exemplary top view of two battery cells showing examples of battery cell orientation angles. DETAILED DESCRIPTION

[0008] Embodiments of the present disclosure are described herein. It should be understood, however, that the disclosed embodiments are merely examples, and other embodiments may take other and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or reduced to show details of specific components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art how to variously utilize the present embodiments.As one of ordinary skill in the art will recognize, various features illustrated and described with reference to any of the figures may be combined with features illustrated in one or more other figures to produce embodiments not explicitly illustrated or described. The combinations of the illustrated features provide representative embodiments for typical applications. However, various combinations and modifications of the features consistent with the teachings of this disclosure may be desired for particular applications or implementations.

[0009] Fig. 1 depicts a schematic representation of a typical plug-in hybrid electric vehicle (PHEV). A typical plug-in hybrid electric vehicle 12 may include one or more electric machines 14 mechanically connected to a hybrid transmission 16. The electric machines 14 may be operable as a motor or generator. Furthermore, the hybrid transmission 16 is mechanically connected to an engine 18. The hybrid transmission 16 is also mechanically connected to a driveshaft 20, which is mechanically connected to the wheels 22. The electric machines 14 may provide propulsion and braking capability when the engine 18 is on or off. The electric machines 14 also serve as generators and may provide fuel economy benefits by recovering energy that would normally be lost as heat in the friction braking system.The electric machines 14 may also enable reduced emissions because the hybrid electric vehicle 12 may be operated in electric mode or hybrid mode under certain conditions to reduce the overall fuel consumption of the vehicle 12.

[0010] A traction battery or battery pack 24 stores and delivers energy that can be used by the electric machines 14. The traction battery 24 typically provides a high-voltage direct current output from one or more battery cell assemblies, sometimes referred to as battery cell stacks, within the traction battery 24. The battery cell assemblies may include one or more battery cells. The traction battery 24 is electrically connected to one or more power electronics modules 26 through one or more contactors (not shown). The one or more contactors isolate the traction battery 24 from other components when opened and connect the traction battery 24 to other components when closed.The power electronics module 26 is also electrically connected to the electric machines 14 and provides the capability to transfer electrical energy bidirectionally between the traction battery 24 and the electric machines 14. For example, a typical traction battery 24 may provide a DC voltage, while the electric machines 14 may require a three-phase AC voltage to operate. The power electronics module 26 may convert the DC voltage to a three-phase AC voltage as required by the electric machines 14. In a regenerative mode, the power electronics module 26 may convert the three-phase AC voltage from the electric machines 14 acting as generators to the DC voltage required by the traction battery 24. The description herein is equally applicable to a pure electric vehicle.For a pure electric vehicle, the hybrid transmission 16 may be a gear box connected to an electric machine 14, and the prime mover 18 may not be present.

[0011] The traction battery 24 not only provides power for propulsion but can also provide power for other vehicle electrical systems. A typical system may include a DC-DC converter module 28 that converts the high-voltage DC output of the traction battery 24 into a low-voltage DC output tailored to other vehicle loads. Other high-voltage loads, such as compressors and electric heaters, can be connected directly to the high voltage without the use of a DC-DC converter module 28. In a typical vehicle, the low-voltage systems are electrically connected to a backup battery 30 (e.g., a 12V battery).

[0012] A Battery Electronic Control Module (BECM) 33 may be in communication with the traction battery 24. The BECM 33 may serve as a controller for the traction battery 24 and may also include an electronic monitoring system that regulates the temperature and state of charge of each of the battery cells. The traction battery 24 may include a temperature sensor 31, such as a thermistor or other temperature indicating device. The temperature sensor 31 may be in communication with the BECM 33 to provide temperature data regarding the traction battery 24. The temperature sensor 31 may also be located on or near the battery cells within the traction battery 24. It is also contemplated that more than one temperature sensor 31 may be used to monitor the temperature of the battery cells.

[0013] For example, the vehicle 12 may be an electric vehicle such as a PHEV, an FHEV, an MHEV, or a BEV, in which the traction battery 24 can be recharged from an external power source 36. The external power source 36 may be a connection to an electrical outlet. The external power source 36 may be electrically connected to the electric vehicle supply equipment (EVSE) 38. The EVSE 38 may provide circuitry and controls for adjusting and regulating the transfer of electrical energy between the power source 36 and the vehicle 12. The external power source 36 may supply direct or alternating electrical power to the EVSE 38. The EVSE 38 may include a charging plug 40 for insertion into a charging port 34 of the vehicle 12. The charging port 34 may be any type of port configured to transfer power from the EVSE 38 to the vehicle 12.The charging port 34 may be electrically connected to a charger or an on-board power converter module 32. The power converter module 32 may condition the power supplied by the EVSE 38 to deliver the correct voltage and current levels to the traction battery 24. The power converter module 32 may communicate with the EVSE 38 via an interface to coordinate the delivery of power to the vehicle 12. The EVSE connector 40 may have pins that fit into corresponding recesses of the charging port 34.

[0014] The various components discussed may have one or more associated controllers for controlling and monitoring the operation of the components. The controllers may communicate via a serial bus (e.g., Controller Area Network (CAN)) or via discrete conductors.

[0015] Battery cells, such as a prismatic cell, may contain electrochemical cells that convert stored chemical energy into electrical energy. Prismatic cells may contain a casing, a positive electrode (cathode), and a negative electrode (anode). An electrolyte allows ions to move between the anode and cathode during a discharge and then move back during a recharge. Poles allow current to flow out of the cell and be used by the vehicle. The poles of each battery cell, when positioned in a multi-cell array, may be aligned adjacent to each other at opposite poles (positive and negative), and a bus bar can help create a series connection between the multiple battery cells.The battery cells can also be arranged in parallel, so that like poles (positive and positive or negative and negative) are adjacent to each other. For example, two battery cells can be arranged with positive poles adjacent to each other, and the next two cells with negative poles adjacent to each other. In this example, the busbar can contact the poles of all four cells.

[0016] The traction battery 24 may be heated and / or cooled using a liquid thermal management system, an air thermal management system, or another method as known in the art. In one example of a liquid thermal management system, and with reference now to Fig. 2, the traction battery 24 may include a battery cell assembly 88 shown supported by a thermal plate 90 to be heated and / or cooled by a thermal management system. The battery cell assembly 88 may include a plurality of adjacently positioned battery cells 92 and structural components. The DC / DC converter module 28 and / or the BECM 33 may also require cooling and / or heating under certain operating conditions. A thermal plate 91 may support the DC / DC converter module 28 and the BECM 33 and assist in thermal management. For example, the DC / DC converter module 28 may generate heat during voltage conversion that may need to be dissipated. Alternatively, the thermal plates 90 and 91 may be in fluid communication with each other and have a common fluid inlet port and a common outlet port.

[0017] In one example, the battery cell assembly 88 may be mounted to the thermal plate 90 such that only one surface of each of the battery cells 92, such as a lower surface, is in contact with the thermal plate 90. The thermal plate 90 and individual battery cells 92 may transfer heat between each other to help control the thermal conditioning of the battery cells 92 within the battery cell assembly 88 during vehicle operation. Uniform thermal fluid distribution and high heat transfer capability are two factors to consider with the thermal plate 90 to enable effective thermal management of the battery cells 92 within the battery cell assemblies 88 and other components therearound.Because heat transfers between the thermal plate 90 and the thermal fluid by conduction and convection, the surface area in a thermal fluid flow field is important for effective heat transfer, both for removing heat and for heating the battery cells 92 at cold temperatures. For example, charging and discharging the battery cells generates heat, which, if not dissipated, can negatively impact the performance and service life of the battery cell assembly 88. Alternatively, the thermal plate 90 can also supply heat to the battery cell assembly 88 when exposed to cold temperatures.

[0018] The thermal plate 90 may include one or more channels 93 and / or a cavity to distribute thermal fluid through the thermal plate 90. For example, the thermal plate 90 may include an inlet port 94 and an outlet port 96 that may be in communication with the channels 93 to provide and circulate the thermal fluid. The positioning of the inlet port 94 and the outlet port 96 relative to the battery cell assemblies 88 may vary. For example, and as shown in Fig. 2, the inlet port 94 and the outlet port 96 may be centrally positioned relative to the battery cell assemblies 88. The inlet port 94 and the outlet port 96 may also be positioned laterally on the battery cell assemblies 88. Alternatively, the thermal plate 90 may define a cavity (not shown) in communication with the inlet port 94 and the outlet port 96 to provide and circulate the thermal fluid. The thermal plate 91 may include an inlet port 95 and an outlet port 97 to supply and remove thermal fluid. Optionally, a thermal interface material (not shown), for example, in the form of a layer, paste, glue, or adhesive, may be applied to the thermal plate 90 and / or 91 beneath the battery cell assembly 88 and / or the DC-DC converter module 28 or the BECM 33, respectively.The layer of thermal interface material can improve heat transfer between the battery cell assembly 88 and the thermal plate 90, for example, by filling hollow areas and / or air pockets between the battery cells 92 and the thermal plate 90. The thermal interface material can also provide electrical insulation between the battery cell assembly 88 and the thermal plate 90. A battery carrier 98 can support the thermal plate 90, the thermal plate 91, the battery cell assembly 88, and other components. The battery carrier 98 can include one or more recesses for receiving thermal plates.

[0019] Different battery pack configurations may be available to accommodate individual vehicle variables, including packaging constraints and power requirements. The battery cell assembly 88 may be contained within a cover or housing (not shown) to protect and enclose the battery cell assembly 88 and other components therearound, such as the DC / DC converter module 28 and the BECM 33. The battery cell assembly 88 may be positioned in a number of different locations, including, but not limited to, under a front seat, under a rear seat, or behind the rear seat of the vehicle. However, it is contemplated that the battery cell assembly 88 may be positioned in any suitable location within the vehicle 12.

[0020] Fig. 3A shows an example of a portion of a traction battery assembly with an air thermal management system and a pair of spaced-apart battery cell assemblies 120. The battery cell assemblies 120 may include a plurality of battery cells 122, as shown in Fig. 3B. The battery cells 122 are configured in a somewhat conventional stacked orientation. A pair of end plates 124 may be located at opposite end surfaces of the battery cell assemblies 120 and may assist in retaining the battery cells 122 therebetween. The end plates 124 may be configured with the respective battery cell assemblies 120, for example, to apply a compressive force to the opposite end surfaces of the battery cell assemblies 120. The battery cell assemblies 120 may be attached to a battery tray 128, for example. A portion of a traction battery housing 132 is shown, which may house the battery cell assemblies 120 and the end plates 124. An arrow 134 pointing in the X direction may represent forward and reverse directions of a vehicle including the battery cell assemblies 120.An arrow 136 pointing in the Y-direction may represent a transverse direction of the vehicle. In this example, the battery cells 122 of the two battery cell assemblies 120 are oriented in a rectangular configuration for cooling by the air thermal management system. In this rectangular configuration, the arrows 138 show examples of airflow paths into the traction battery housing 132 that run along the exterior portions of the traction battery housing 132 in the Y-direction. The arrows 142 show examples of airflow paths that run in the X-direction over and between the battery cells 122, for example, to assist in cooling the battery cells 122. As shown, the airflow makes a turn of approximately ninety degrees to travel in the X-direction.Arrow 144 shows an example of an airflow path for air exiting the traction battery housing 132 in the Y direction after it has again made an approximately ninety-degree turn from the path of air moving over the battery cells 122. The two battery cell assemblies 120 define an X length equal to a dimension 150.

[0021] Fig. 4A shows an example of a portion of another traction battery assembly that may include an air thermal management system and a pair of angled battery cell assemblies 160 spaced apart from each other. The battery cell assemblies 160 may include a plurality of battery cells 162, as shown in Fig. 4B. Each battery cell 162 may include a pair of opposing side surfaces 162a and a pair of opposing front surfaces 162b. Each battery cell 162 may also include four vertical edges 162c. A pair of end plates 164 may be located at longitudinally opposite ends of the battery cell assemblies 160 and may assist in retaining the battery cells 162 therebetween. For example, the end plates 164 may be configured with the respective battery cell assemblies 160 to apply a compressive force to the battery cells 162. The battery cell assemblies 160 may be supported by a support component, such as a battery tray 168. The battery cell assemblies 160 may also be supported and retained by spacers, retention features, and / or rails mounted to the battery tray 168 and the end plates 164, as further described below.A portion of a traction battery housing 172 is shown, which may house the battery cell assemblies 160 and the end plates 164. An X-direction arrow 176 represents a forward and rearward direction of a vehicle incorporating the battery cell assemblies 160. A Y-direction arrow 178 represents a transverse direction of the vehicle. In this example, and in contrast to the embodiment shown in FIG. Fig. 3A, the battery cells 162 of the battery cell assemblies 160 are oriented in a feathered configuration for cooling by the air thermal management system.

[0022] For example, in the feathering configuration, the battery cells 162 may be stacked such that the centers of the battery cells 162 are aligned along a longitudinal assembly center axis 181, and such that outer portions of the battery cells 162 form step configurations that extend along longitudinal sides of the battery cell assemblies 160. In this example, the side surfaces 162a, the front surfaces 162b, and the vertical edges 162c may at least partially define the step configuration of the outer portions of the battery cells 162. A "step configuration," as used herein, also includes square wave configurations.

[0023] In the feathering configuration, the battery cells 162 may be configured to define a plurality of passageways between them, which may be diagonally oriented relative to the longitudinal array centerline 181. The passageways may provide a path for airflow to assist in thermal management of the battery cells 162 and / or may provide space for cell spacers. For example, an inlet (not shown) of the traction battery housing 172 may be in fluid communication with the passageways such that air flows longitudinally from the inlet and then flows diagonally between the battery cells 162 relative to the longitudinal array centerline 181. The battery cells 162 may be oriented at an acute angle relative to an assembly centerline axis 183 between the assemblies that extends parallel to the longitudinal array centerlines 181.

[0024] The arrows 180 show examples of airflow paths into the traction battery housing 172 that run in the Y direction. The arrows 182 show examples of airflow paths that run over and between the battery cells 162 according to an angle of orientation of the battery cells 162, for example, to assist in cooling the battery cells 162. As shown in this example and in Fig. 4C, the airflow in the plumage formation makes a turn of approximately sixty degrees (shown as angle 182a) to move over and between the battery cells 162. Compared to the ninety-degree angle as in the example of Fig. 3A, the airflow in the plumage formation can be increased with a turn angle of less than ninety degrees, where the airflow comes from the Y direction, to cool the battery cells 162. The reduced angle, where the airflow comes from the Y direction, can also reduce overall system pressure drop because the angle of change at which the air flows through the battery cell assemblies 160 is reduced. Arrow 184 shows an example of an airflow path for air flowing over and between the battery cells 162 on its route before exiting the traction battery enclosure 132 in the Y direction after making a turn of substantially thirty degrees (shown as angle 182b) from the path of the air moving over the battery cells 162. Although angles 182a and 182b, which are approximately sixty degrees and sixty degrees, respectively,thirty degrees, it is contemplated that other configurations of the battery cells 162 are available that may utilize alternative angles for turns over which air streams may move to assist in cooling the battery cells 162.

[0025] The feathered configuration of the battery cells 162 may reduce the packaging space compared to the rectangular configuration of the battery cells 122. For example, the two battery cell assemblies 160 may define an X-length equal to a dimension 186. Assuming the battery cells 122 and the battery cells 162 are the same size, the dimension 186 is smaller than the dimension 186. The shorter dimension 186 may open up additional traction battery placement options within the vehicle. For example, vehicles with narrow rear seats may not offer sufficient space to place a traction battery underneath. In such vehicles, the traction battery, which includes the rectangular configuration of the battery cell assemblies 120, as shown in Fig. 3A may not be suitable for this purpose, while the traction battery incorporating the feathering of the battery cell 162 may be suitable. Fig. 4D shows the battery cell assemblies 160 in a configuration that may be suitable for a liquid thermal management system, in which the battery cell assemblies 160 are closer together than when used with the air thermal management system, so dimension 187 may be smaller than dimension 150 and dimension 186. In this example, the battery tray 168 may include a recess to receive a thermal plate (not shown) for use with the liquid thermal management system. The thermal plate may be in thermal communication with the battery cells 162 to dissipate heat therefrom.

[0026] The battery cell assemblies 160 in the feathering configuration may also include structural components to assist in pressurizing the battery cells 162. These components may assist in preventing displacement of the battery cells 162 by providing structural reinforcement under certain conditions regarding the angle of orientation of the battery cells 162.

[0027] Fig. 5 shows an example of a support structure 300 for supporting and holding the cell assemblies 160. The support structure 300 may include the pair of end plates 164, a pair of upper support beams 306, and a pair of lower support beams 308 (only one of the lower support beams 308 is shown in Fig. 5 visible). The Fig. 6A and Fig. 6B are perspective views of the end plates 164. The end plates 164 may have a triangular prism shape or wedge shape and may each include an inner surface 312, an outer surface 314, and side surfaces 316. A "prism shape" that is triangular or rectangular, as used herein to refer to a component, does not necessarily mean a geometrically perfect prism shape. For example, features or elements of the component, such as recesses, protrusions, or manufacturing defects, may be such that the component, while generally prism-shaped, does not necessarily have a geometrically perfect prism shape. Although the Fig. 6A and Fig. 6B show the end plate 164 with two side surfaces 316, it is contemplated that a configuration of the end plate 164 may also include only one side surface 316, such that a plan view of the end plate 164 resembles a triangle. The inner surfaces 312 of the end plates 164 may define planes that are parallel to one another. "Parallel," as used herein to refer to orientations between components or axes, does not necessarily imply geometrically perfect parallelism. For example, components may be slightly offset from one another, for example, during an assembly process, and may therefore be substantially parallel to one another rather than geometrically perfectly parallel. The inner surfaces 312 may be oriented at an angle 412 relative to the longitudinal assembly center axis 181 or the upper support beams 306 or the lower support beams 308, as in Fig. 6C. The angle 412 may be an acute angle. The outer surfaces 314 of the end plates 164 may define planes that are parallel to each other. The end plates 164 may each define a pair of upper inside corners 322. The upper support brackets 306 may extend between the upper inside corners 322 of the end plates 164. It is contemplated that the upper support brackets 306 and the lower support brackets 308 may consist of more than one interlocking component or may be a single component. The upper and lower support rails may, for example, be used with the support structure 300 to extend between the end plates 164. These upper and lower rails may define the respective spacer guides 332, the respective cell guides 336, and the respective shingle flashings 354.Alternatively, the spacer guides 332, the cell guides 336 and the shingle moldings 354 may be attached to the respective upper support bracket 306 and the respective lower support bracket 308.

[0028] The end plates 164 and the upper support brackets 306 and / or the lower support brackets 308 may define a rectangular prism. The end plates 164, the upper support brackets 306, and the lower support brackets 308 may be configured to interact to generate compressive forces against the battery cells 162 and to hold the battery cells 162 therebetween. The upper support brackets 306 and the lower support brackets 308 may include guides to assist in orienting the battery cells 162 and a plurality of cell spacers 330 at an angle parallel to an orientation angle of the inner surfaces 312 of the end plates 164.

[0029] The Fig. 7A and Fig. 7B, for example, shows an example of the spacer guides 332 and the cell guides 336 defined by a portion of the upper support beams 306. The spacer guides 332 may be sized to receive a portion of an upper corner of one of the cell spacers 330 and orient it at an angle parallel to the angle of the inner surfaces 312 of the end plates 164. The spacer guides 332 and the cell guides 336 may be extensions from the upper support beams 306, which may contact and retain the cell spacers 330 and the battery cells 162, respectively. Alternatively, the spacer guides 332 and the cell guides 336 may be, for example, notches or recesses in the upper support beams 306.The cell guides 336 may be sized to receive a portion of an upper corner of the battery cells 162 and oriented at an angle parallel to the angle of the inner surfaces 312 of the end plates 164. The spacer guides 332 and the cell guides 336 may be configured and spaced relative to each other to define passageways between the cell spacers 330. The battery cells 162 may be placed within at least a portion of the passageways in certain thermal management systems, such as an air thermal management system, and the passageways may also provide a path for air to flow and assist in cooling the battery cells 162.

[0030] Fig. 8 shows an example of an air system spacer 342 shown as being held between portions of the upper support beams 306 and the lower support beams 308. The air system spacer 342 may be used with an air-cooled thermal management system. The air system spacer 342 may define one or more ribs 346. The ribs 346 may extend across the air system spacer 342 and assist in defining paths or passageways for airflow between the air system spacer 342 and the adjacent battery cells 162. A base beam 348 may support a lower portion of the air system spacer 342 and also assist in confining airflow within the passageways. The base beam 348 may also act as an electrical insulator for the battery cells 162.

[0031] Fig. 9 shows an example of a fluid system spacer 350 shown as being held between portions of the upper support beams 306 and the lower support beams 308. The fluid system spacer 350 may be used with a liquid-cooled thermal management system. A lower portion of the fluid system spacer 350 may contact a supporting surface, such as a thermal plate (not shown), to assist in dissipating heat from the battery cells 162 to the thermal plate. The shingle moldings 354 may extend from the lower support beams 308, as shown in FIGS. Fig. 8 and Fig. 9. The shingle fittings 354 may be sized to receive lower corner portions of the air system spacers 342, the fluid system spacers 350, and the battery cells 162. The shingle fittings 354 may assist the spacer guides 332 and the cell guides 336 in retaining the cell spacers and the battery cells 162 to prevent or minimize displacement of the battery cells 162 under certain conditions.

[0032] Fig. For example, Figure 10 shows a detailed view of a portion of the battery cell assemblies 160 that include zones or regions 220 where the upper support beams 306 can assist in preventing or minimizing displacement of the battery cells 162 when oriented in the feather formation. In these regions 220, an angle of orientation of the battery cells 162 can be such that the battery cells 162 will shift upon compressive forces applied to the battery cells 162. Fig.For example, Figure 11 shows an exemplary top view of two of the battery cells 162 oriented in the feathering configuration. The battery cells 162 may be oriented at an angle Θ relative to the opposing front surfaces 162b of the battery cells 162 and the longitudinal assembly center axis 181. The angle Θ may be based on a coefficient of friction of a surface supporting the battery cells 162 and the compressive forces applied to the battery cells 162 for retention purposes. Friction may not stabilize the battery cells 162, for example, under compression and beyond certain degrees of angle Θ. Degrees of angle Θ at which the battery cells 162 are stable when compressive forces are applied may be referred to as stable degrees.Degree values ​​for the angle Θ at which the battery cells 162 shift when compressive forces are applied may be referred to as the displacement angle value. The angle Θ may have different stable angle values ​​and displacement angle values ​​for different traction battery assemblies due to varying friction coefficients for the surfaces supporting the battery cells 162 and varying compressive forces that may be applied to the battery cells 162. In one example, the angle Θ is between 90 degrees and 68.2 degrees.

Claims

[1] Support structure (300) for a battery cell assembly (160), comprising: a pair of end plates (164) having a triangular prism shape, having opposing parallel inner surfaces (312) configured to exert a compressive force on battery cells (162) placed therebetween, and parallel outer surfaces (314) that are not parallel to the inner surfaces (312); and a pair of opposing support beams (306, 308) extending between the end plates (164), the end plates (164) and the beams (306, 308) being arranged that the outer surfaces (314) and the supports (306, 308) define a rectangular prism; characterized by , that each of the support brackets (306, 308) defines a support feature having a first portion attached to respective inner corners (322) of the end plates (164), a second portion having a spacer guide (332) for receiving and orienting a corner portion of a cell spacer (330) such that the spacer (330) is parallel to the inner surfaces (312), and a third portion having a cell guide (336) for receiving and orienting a corner portion of a battery cell (162) such that the cell (162) is parallel to the inner surfaces (312). [2] The support structure (300) of claim 1, wherein the inner surfaces (312) are oriented at an acute angle (Θ) relative to at least one of the beams (306, 308), and wherein the acute angle (Θ) has a displacement angle value. [3] The support structure of claim 2, wherein the displacement angle value is based on a surface friction coefficient of a battery carrier (168) configured to support the battery cells (162) and an amount of compressive force. [4] The support structure (300) of claim 1, wherein each of the support beams (306, 308) further defines a plurality of alternating first and second guides between the opposing inner corners (322). [5] The support structure (300) of claim 4, further comprising a plurality of cell spacers (330) interposed between the end plates (164) having corners oriented by the first guides such that the spacers (330) are parallel to the inner surfaces (312), each of the cell spacers (330) defining a plurality of ribs (346) spaced at intervals and extending outwardly on both sides of the spacer (330). [6] Support structure (300) according to claim 4, further comprising: a thermal plate (90) placed under a battery cell area between the end plates (164); and a plurality of cell spacers (330) placed between the end plates (164) and upper corners held by the first guides, and lower corners in at least partial contact with the thermal plate (90), and which are oriented such that the spacers (330) are parallel to the inner surfaces (312). [7] Support structure (300) for a battery cell assembly (160), comprising: a pair of wedge-shaped end plates (164) each having inner corners (322); and a pair of support beams (306, 308) extending between the inner corners (322), wherein the end plates (164) and the supports (306, 308) are configured such that the end plates (164) exert a compressive force on battery cells (162) placed therebetween in a direction other than that defined by the supports (306, 308), wherein the end plates (164) further each have outer surfaces (314) which are parallel to each other, inner surfaces (312) which are oriented parallel to each other and at an acute angle (Θ) relative to the respective outer surfaces (314), at least one side surface (316), which extends between the outer and inner surfaces (312, 314) and have upper surfaces, and wherein the inner corners (322) are each defined by an intersection of the inner surface (312), the upper surface and the side surface (316), characterized by , that the supports (306, 308) each define a plurality of first guides sized to receive and orient a portion of a corner of a cell spacer (330) such that the spacer (330) is parallel to the inner surfaces (312), and wherein the supports (306, 308) each further define a plurality of second guides sized to receive and orient a portion of a corner of a battery cell (162) such that the battery cell (162) is parallel to the inner surfaces (312). [8] Support structure (300) according to claim 7, further comprising: a pair of outer spacers each adjacent to the respective inner surfaces (312), oriented parallel to the inner surfaces (312), and at least partially disposed within four of the first guides adjacent the inner corners (322) of the end plates (164); and a plurality of inner spacers spaced at intervals between the pair of outer spacers, oriented parallel to the inner surfaces (312) and at least partially set within the other of the first guides between the four of the first guides adjacent to the inner corners (322). [9] The support structure (300) of claim 8, wherein the end plates (164) and the support beams (306, 308) are configured to support and orient the battery cells (162) such that the battery cells (162) are parallel to the inner surfaces (312). [10] Support structure (300) for a battery cell assembly (160), comprising: a pair of wedge-shaped end plates (164) each having inner corners (322); and a pair of support beams (306, 308) extending between the inner corners (322), wherein the end plates (164) and the supports (306, 308) are configured such that the end plates (164) exert a compressive force on battery cells (162) placed therebetween in a direction other than a direction defined by the supports (306, 308), wherein the end plates (164) each define an inner surface (312) oriented at an angle (Θ) relative to the support supports (306, 308) that is equal to a displacement angle value, which is determined by a surface friction coefficient of a battery carrier (168) arranged to support the battery cells (162) and an amount of pressure force, characterized by , that the support brackets (306, 308) each define a plurality of first guides sized to receive a portion of a plurality of corners of cell spacers (330) such that the spacer (330) is oriented at the angle (Θ) and such that passages defined between the cell spacers (330) provide a path for airflow. [11] Traction battery assembly comprising: a pair of end plates (164), each having a triangular prism shape; a pair of upper rails extending between each of the end plates (164) and define a plurality of first guides sized to receive a portion of an upper corner of a spacer (330); and a plurality of cell spacers (330) interposed between the end plates (164) which are diagonally arranged such that the spacers (330) are oriented at an acute angle (Θ) relative to the upper rails and such that at least a portion of the upper corners of the spacers (330) are held by the first guides. [12] The assembly of claim 11, wherein the upper rails each further define a plurality of second guides sized to receive a portion of an upper corner of a battery cell (162) such that a front surface (162b) of the battery cell (162) is oriented parallel to a front surface (162b) of the cell spacers (330). [13] The assembly of claim 11, wherein the cell spacers (330) are configured to define a plurality of airflow passages therebetween and are diagonally oriented relative to the upper rails. [14] The assembly of claim 11, further comprising a pair of lower rails extending between each of the end plates (164) and defining a plurality of shingle moldings (354) sized to receive a portion of a lower corner of a battery cell (162). [15] The assembly of claim 11, further comprising a pair of lower rails extending between each of the end panels (164) and defining a plurality of shingle moldings (354) sized to receive a portion of a lower corner of a spacer (330). [16] The assembly of claim 11, wherein the acute angle (Θ) has a displacement angle value based on a surface friction coefficient of a battery tray (168) supporting the assembly and an amount of compressive force exerted by the end plates (164) on a plurality of cells (162) interposed therebetween and supported by the battery tray (168).

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