CN117650329A - Inter-cell stack connection for traction battery packs - Google Patents

Abstract

The present disclosure provides "inter-cell stack connection for traction battery packs". An electrical connection system for electrically connecting a cell stack of a traction battery pack is provided. An example electrical connection system may include a first high voltage terminal of a first cell stack and a second high voltage terminal of a second cell stack. The first high voltage terminal may be mounted to a first cross member beam of a first cell stack and the second high voltage terminal may be mounted to a second cross member beam of a second cell stack. A first high voltage terminal may be arranged and coupled to the second high voltage terminal to electrically connect the first cell stack and the second cell stack.

Description

Inter-cell stack connection for traction battery packs

Cross Reference to Related Applications

The present disclosure claims priority from U.S. provisional application No. 63/403,445 filed on 9/2022, which is incorporated herein by reference.

Technical Field

The present disclosure relates generally to traction battery packs and, more particularly, to systems and methods for electrically connecting cell stacks of traction battery packs.

Background

Motorized vehicles include a traction battery pack for powering the vehicle's motor and other electrical loads. The traction battery pack includes a plurality of battery cells and various other battery internal components that support propulsion of the electric vehicle.

Disclosure of Invention

Traction battery packs according to exemplary aspects of the present disclosure include, among other things: a first cell stack including a first cross member beam; a first high voltage terminal mounted to the first cross member beam; a second cell stack including a second cross-member beam; and a second high voltage terminal mounted to the second cross member beam. The first high voltage terminal is coupled to the second high voltage terminal to electrically connect the first cell stack and the second cell stack.

In a further non-limiting embodiment of the aforementioned traction battery pack, a mechanical fastener couples the first high voltage terminal to the second high voltage terminal.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the first high voltage terminal includes a first electrical contact portion and the second high voltage terminal includes a second electrical contact portion disposed side-by-side with the first electrical contact portion along a vertical axis. The mechanical fastener extends along the vertical axis to couple the first high voltage terminal to the second high voltage terminal.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the first high voltage terminal includes a first electrical contact portion and the second high voltage terminal includes a second electrical contact portion disposed side-by-side with the first electrical contact portion along a horizontal axis. The mechanical fastener extends along the horizontal axis to couple the first high voltage terminal to the second high voltage terminal.

In a further non-limiting embodiment of any of the foregoing traction battery packs, a weld bead couples the first high voltage terminal to the second high voltage terminal.

In a further non-limiting embodiment of any of the foregoing traction battery packs, a bus bar couples the first high voltage terminal to the second high voltage terminal.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the first high voltage terminal includes a male portion configured to engage a female portion of the second high voltage terminal to electrically connect the first cell stack and the second cell stack.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the concave portion includes a first arm, a second arm, and a slot extending between the first arm and the second arm. The male portion is received within the slot to electrically connect the first and second cell stacks.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the first and second cross-member beams establish a cross-member assembly disposed between the first and second cell stacks of the traction battery pack.

In a further non-limiting embodiment of any of the foregoing traction battery packs, a vent channel is disposed between the first and second cross member beams.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the housing cover provides a vertically upper side of the ventilation channel and the housing tray or heat exchanger plate provides a vertically lower side of the ventilation channel.

In a further non-limiting embodiment of any of the foregoing traction battery packs, a vent opening formed through the first cross member beam establishes a vent path between the first cell stack and the vent channel.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the first cell stack includes a plurality of battery cells supported between the first and third cross-member beams, and the second cell stack includes a further plurality of battery cells supported between the second and fourth cross-member beams.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the first high voltage terminal includes a base mounted to the first cross member beam and an electrical contact portion extending away from the base at a lateral angle.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the first high voltage terminal includes a first electrical contact portion having a first aperture and the second high voltage terminal includes a second electrical contact portion having a second aperture coaxially aligned with the first aperture.

A traction battery pack according to another exemplary aspect of the present disclosure includes, among other things: a first cell stack; a second cell stack; a cross member assembly disposed between the first cell stack and the second cell stack; and an electrical connection system for electrically connecting the first cell stack and the second cell stack. The electrical connection system includes a first high voltage terminal of the first cell stack, a second high voltage terminal of the second cell stack, and a mechanical fastener joining the first high voltage terminal to the second high voltage terminal.

In another non-limiting embodiment of any of the foregoing traction battery packs, the mechanical fastener comprises a weld bead.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the weld bead joins a busbar to the first high voltage terminal and the second high voltage terminal.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the mechanical fastener comprises a bolt and nut assembly.

In a further non-limiting embodiment of any of the foregoing traction battery packs, the first high voltage terminal is mounted to a first cross member beam of the cross member assembly and the second high voltage terminal is mounted to a second cross member beam of the cross member assembly.

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

Various features and advantages of this 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.

Drawings

Fig. 1 schematically shows an electrically powered vehicle.

Fig. 2 is an exploded perspective view of a traction battery pack for an electrically powered vehicle.

Fig. 3 is a cross-sectional view through section 3-3 of fig. 2.

Fig. 4 illustrates an exemplary cell stack of the traction battery pack of fig. 2 and 3.

Fig. 5 illustrates an exemplary electrical connection system for connecting adjacent cell stacks of a traction battery pack.

Fig. 6 illustrates another exemplary electrical connection system for connecting adjacent cell stacks of a traction battery pack.

Fig. 7A and 7B illustrate another exemplary electrical connection system for connecting adjacent cell stacks of a traction battery pack.

Fig. 8 illustrates yet another exemplary electrical connection system for connecting adjacent cell stacks of a traction battery pack.

Detailed Description

The present disclosure details an electrical connection system for electrically connecting a cell stack of a traction battery pack. An example electrical connection system may include a first high voltage terminal of a first cell stack and a second high voltage terminal of a second cell stack. The first high voltage terminal may be mounted to a first cross member beam of a first cell stack and the second high voltage terminal may be mounted to a second cross member beam of a second cell stack. A first high voltage terminal may be arranged to be coupled to the second high voltage terminal to electrically connect the first cell stack and the second cell stack. These and other features are discussed in more detail in the following paragraphs of this detailed description.

Fig. 1 schematically illustrates an electrically powered vehicle 10. The motorized vehicle 10 may include any type of motorized driveline. In one embodiment, the motorized vehicle 10 is a Battery Electric Vehicle (BEV). However, the concepts described herein are not limited to BEVs and are extendable to other motorized vehicles, including, but not limited to, hybrid Electric Vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), fuel cell vehicles, and the like. Thus, although not specifically shown in the exemplary embodiment, the powertrain of the motorized vehicle 10 may be equipped with an internal combustion engine that may be employed alone or in combination with other power sources to propel the motorized vehicle 10.

In the illustrated embodiment, the motorized vehicle 10 is depicted as an automobile. However, the motorized vehicle 10 may alternatively be a Sport Utility Vehicle (SUV), van, pick-up truck, or any other vehicle configuration. Although specific component relationships are shown in the drawings of the present disclosure, the illustrations are not intended to limit the disclosure. The layout and orientation of the various components of the motorized vehicle 10 are schematically illustrated and may vary within the scope of the present disclosure. Furthermore, the various figures attached to this disclosure are not necessarily drawn to scale, and some features may be exaggerated or minimized to emphasize certain details of particular components or systems.

In the illustrated embodiment, the motorized vehicle 10 is a pure electric vehicle propelled solely by electric power (such as by one or more electric machines 12) without the assistance of an internal combustion engine. The electric machine 12 may operate as an electric motor, a generator, or both. The electric machine 12 receives electrical power and may convert the electrical power into torque for driving one or more wheels 14 of the motorized vehicle 10.

The voltage bus 16 may electrically couple the motor 12 to a traction battery pack 18. Traction battery pack 18 is an exemplary motorized vehicle battery. Traction battery pack 18 may be a high voltage traction battery pack assembly including a plurality of battery cells configured to output power to power 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 power the motorized vehicle 10.

The traction battery pack 18 may be secured to an underbody 20 of the motorized vehicle 10. However, it is within the scope of the present disclosure that traction battery pack 18 may be located elsewhere on electric vehicle 10.

Fig. 2 and 3 show further details associated with the traction battery pack 18 of the motorized vehicle 10. The traction battery pack 18 may include a plurality of cell stacks 22 housed within an interior region 30 of the housing assembly 24. The housing assembly 24 of the traction battery pack 18 may include a housing cover 26 and a housing tray 28. The housing cover 26 may be secured (e.g., bolted, welded, adhered, etc.) to the housing tray 28 to provide an interior region 30 for receiving the cell stack 22 and other battery internal components of the traction battery pack 18.

Each cell stack 22 may include a plurality of battery cells 32. The battery cells 32 of each cell stack 22 may be stacked side-by-side with respect to one another along a stack axis a. The battery cells 32 store and supply electrical power for powering the various components of the motorized vehicle 10. Although a particular number of cell stacks 22 and battery cells 32 are shown in the various figures of the present disclosure, the traction battery pack 18 may include any number of cell stacks 22, with each cell stack 22 having any number of individual battery cells 32.

In one embodiment, the battery cells 32 are lithium ion pouch cells. However, battery cells having other geometries (cylindrical, prismatic, etc.) and/or chemistries (nickel-metal hydride, lead acid, etc.) may alternatively be utilized within the scope of the present disclosure.

One or more structural thermal barriers 34 may be disposed along a respective cell stack axis a of each cell stack 22. The structural thermal barrier 34 may divide each cell stack 22 into two or more groups or compartments 36 of battery cells 32. Each compartment 36 may hold one or more of the battery cells 32 within one of the cell stacks 22. In one embodiment, the battery cells 32 of each cell stack 22 are held within one of the four compartments 36. However, other configurations are possible within the scope of the present disclosure, including configurations utilizing a greater or lesser number of compartments 36.

The battery cells 32 of each cell stack 22 may be disposed between a pair of cross-member beams 38. The cross-member beam 38 may be configured to retain the battery cells 32 and at least partially delineate the cell stack 22.

The cross member beams 38 may be adhesively secured to the housing cover 26 and to the housing tray 28 or to heat exchanger plates 44 located between the housing tray 28 and the one or more cell stacks 22. The adhesive may seal these interfaces to inhibit battery cell venting byproducts from escaping through these areas.

The immediate vicinity of the cross member beam 38 may establish a cross member assembly 40 disposed between adjacent cell stacks 22 of the traction battery pack 18. For example, the cross member assembly 40 may be configured to transfer loads applied to the sides of the motorized vehicle 10. Each cross member beam 38 of the cross member assembly 40 may be a structural beam that may help accommodate tensile loads from the expansion and compression loads of the battery cells 32. Thus, the cross member assembly 40 is configured to increase the structural integrity of the traction battery pack 18.

The cross member assembly 40 may also establish a battery pack venting system for transferring battery cell venting byproducts from the traction battery pack 18 during a battery thermal event. For example, the cross-member assembly 40 may establish a channel 42 (best shown in fig. 3) that conveys the cell ventilation byproducts from the cell stack 22 toward a location where the cell ventilation byproducts may be exhausted from the traction battery pack 18.

In the exemplary embodiment shown in fig. 3, adjacent first and second cross member beams 38 may establish first and second sides, respectively, of a channel 42 of a cross member assembly 40. Further, a vertically upper side of the channels 42 may be established by the housing cover 26, and a vertically lower side of the channels 42 may be established by the heat exchanger plates 44 positioned against the housing tray 28. In another embodiment, the heat exchanger plates 44 may be omitted and the vertically underside of the channels 42 may be established by the housing tray 28. For purposes of this disclosure, vertical and horizontal are the general orientations of the ground-referenced and traction battery pack 18 when installed within the motorized vehicle 10 of fig. 1.

In one embodiment, the cell stack 22, the cross member assembly 40, and the corresponding channels 42 extend longitudinally in the transverse direction of the vehicle. However, other configurations are also contemplated within the scope of the present disclosure.

With continued reference to fig. 2 and 3, fig. 4 illustrates an exemplary cell stack 22 of the traction battery pack 18. The additional cell stack 22 of the traction battery pack 18 may comprise the same design as the cell stack 22 shown in fig. 4, or a similar design, as its electrical connection to an adjacent cell stack may be varied to complete the necessary electrical circuits, as will be appreciated by those of ordinary skill in the art having the benefit of this disclosure.

The cell stack 22 may include a plurality of cell packets 46 stacked horizontally between a pair of cross-member beams 38 and longitudinally (e.g., side-by-side along the cell stack axis a) between a pair of compression plates 50. The total number of cell packets 46 disposed within the cell stack 22 may vary and, thus, is not intended to limit the present disclosure.

Each compression plate 50 may be made of a plastic material. The compression plate 50 may be configured to accommodate and maintain compression of the cell stack 22 along the cell stack axis a. Compression plates 50 may be attached to cross member beams 38. In one embodiment, compression plate 50 includes tabs 54 that are received by cross member beam 38.

Each cell pouch 46 of the cell stack 22 may include a combination of battery cells 32, one or more structural thermal barriers 34, and one or more cell expansion pads 48 stacked together along a cell stack axis a. An exemplary stacked configuration of each cell pouch 46 may include the following arrangement of subcomponents: battery cell 32-cell expansion pad 48-structural thermal barrier 34-cell expansion pad 48-battery cell 32-cell expansion pad 48. However, it is within the scope of the present disclosure that the battery cell pouch 46 may embody various other stacked arrangements/configurations.

For example, the various subcomponents of each cell pouch 46 may be secured together using an adhesive (such as a strip of double-sided tape 52). Strips of double-sided tape 52 may be interspersed between each pair of adjacent sub-components of the cell pouch 46.

The structural thermal barriers 34 may each comprise a single-piece structure or a multi-layer sandwich structure configured to slow or even prevent thermal propagation across the cell stack 22 between the cell packets. In one embodiment, the structural thermal barrier 34 may be made of, for example, a metallic material (such as stainless steel or aluminum) or a thermoplastic material. In another embodiment, the structural thermal barrier 34 comprises one or more insulating materials, such as aerogel materials or foam materials. However, other materials or combinations of materials may be utilized to provide insulating properties to the structural thermal barrier 34 within the scope of the present disclosure.

The cell expansion pad 48 may include a compliant material for accommodating battery cell expansion. The compliant material may include, for example, polyurethane foam or silicone foam. However, other materials or combinations of materials may be utilized to provide compliant properties to the cell extension pad 48 within the scope of the present disclosure.

Each cross member beam 38 may include a beam body 74 and one or more reinforcement sections. In the illustrated embodiment, the cross member beam 38 includes an upper or first reinforcing section 76 and a lower or second reinforcing section 78. However, other configurations are also contemplated within the scope of the present disclosure.

The beam body 74 may be a unitary structure that includes an upper portion 83, a lower portion 82, and an intermediate portion 84 extending between and connecting the upper portion 83 and the lower portion 82. The upper portion 83 may establish an upper platform 86 of the cross member beam 38 and the lower portion 82 may establish a lower base 88 of the cross member beam 38. When positioned within the housing assembly 24 of the traction battery pack 18 in the manner shown in fig. 3, the upper platform 86 may interface with the housing cover 26 and the lower base 88 may interface with the heat exchanger plates 44 or the housing tray 28.

The beam body 74 of each cross member beam 38 may be made of any suitable thermoplastic material. In one embodiment, the beam body 74 is overmolded around each of the first and second reinforcement sections 76, 78. Thus, the first reinforcing section 76 may extend inside the upper portion 83 of the beam body 74, and the second reinforcing section 78 may extend inside the lower portion 82 of the beam body 74. Accordingly, the first and second reinforcement sections 76, 78 may be positioned to structurally reinforce selected portions (e.g., stress areas) of the beam body 74.

In one embodiment, the beam body 74, the first reinforcement section 76, and the second reinforcement section 78 each comprise substantially equal lengths. In other embodiments, the length of the beam body 74 may be greater than the respective lengths of the first and second reinforcement sections 76, 78.

In one embodiment, the first and second reinforcing sections 76, 78 are pultrusions, which implies the structure of these beam-like sections. Those of ordinary skill in the art having the benefit of this disclosure will understand how to structurally distinguish a pultruded beam structure from another type of structure, such as an extruded beam, for example.

The first and second reinforcing sections 76, 78 may be manufactured as part of a pultrusion process utilizing glass or carbon fibers (unidirectional or multidirectional mats) and a thermosetting resin. As part of the pultrusion process used to fabricate the first and second reinforcing sections 76, 78, a plurality of glass or carbon fiber strands may be pulled through the thermosetting resin. The first and second reinforcement sections 76, 78 may then be overmolded by the beam body 74 to provide the desired cross-section of the cross-member beam 38. The beam body 74 may be made of any suitable thermoplastic material.

Each cross-member beam 38 of the cell stack 22 may include a plurality of vent openings 56 for passing cell vent byproducts through the beam and into one of the channels 42 (note that the channels 42 are best shown in fig. 3). Thus, the vent openings 56 provide a path for battery cell vent byproducts to move through the cross member beam 38 and into the channel 42 as needed during a vent event.

The vent opening 56 may be formed through a beam body 74 of the cross member beam 38. In one embodiment, the vent opening 56 is formed through the middle portion 84 of the beam body 74. The ventilation openings 56 may be covered, such as by a segmented membrane 55 (see fig. 3), when the battery cells 32 of the cell stack 22 are not vented. The increase in pressure differential associated with one or more vents in the battery cells 32 may rupture a partial section of the segmented membrane 55, allowing battery cell venting byproducts to enter the channel 42 through the venting opening 56 of the individual cell packet 46 for experiencing a thermal event. When a single cell packet 46 experiences a thermal event to release battery cell ventilation byproducts into the channel 42, a localized section of the segmented membrane 55 may locally rupture. The cell ventilation byproducts may exit from one cell pouch 46 on both sides of the cell stack 22.

Each cross-member beam 38 may additionally include a plurality of cell tab openings 60 disposed vertically below the vent openings 56. The cell tab openings 60 may be formed through the beam body 74. In one embodiment, the cell tab openings 60 are formed through the middle portion 84 of the beam body 74.

Each cell tab opening 60 may be configured to receive a cell tab terminal 62 of a battery cell 32. Cell tab terminals 62 extend from the battery cell housing. For example, an aluminum film may provide the battery cell housing.

In one embodiment, each cell tab opening 60 may receive one cell tab terminal 62. In another embodiment, each cell tab opening 60 may be sized to receive a cell tab terminal 62 from a plurality of adjacent battery cells 32. During a thermal event, in addition to the vent openings 56, battery vent byproducts may also vent at least partially through each cell tab opening 60.

The cell stack 22 may additionally include one or more high voltage terminals 58. The high voltage terminal 58 may be mounted to one of the cross member beams 38 of the cell stack 22 and may also be connected to one or more cell tab terminals 62 of the cell stack 22.

Each high voltage terminal 58 may include a base 66 and an electrical contact portion 68. For example, the base 66 may be mounted to a portion of the cross-member beam 38, such as to the beam body 74, and the electrical contact portions 68 may extend away from the base 66 at a lateral angle (e.g., in a direction away from the cell packets 46 of the cell stack 22). As discussed further below, the high voltage terminals 58 may establish a portion of an electrical connection system for electrically connecting the cell stack 22 to an adjacent cell stack of the traction battery pack 18.

In one embodiment, the high voltage terminal 58 is made of a metallic material such as copper, aluminum, or brass, for example. However, it is within the scope of the present disclosure that additional materials or combinations of materials may be utilized to construct the high voltage terminal 58.

With continued reference to fig. 1-4, fig. 5 illustrates an electrical connection system 64 for electrically connecting a first cell stack 22A and an adjacent second cell stack 22B of the traction battery pack 18. The electrical connection system 64 may connect the first cell stack 22A and the second cell stack 22B in a series string configuration or a parallel string configuration. Although a single electrical connection system 64 is shown in fig. 5, the traction battery pack 18 may include multiple electrical connection systems for achieving the necessary voltage and power levels to support electrical propulsion of the motorized vehicle 10.

The electrical connection system 64 may be established by the first high voltage terminal 58A of the first cell stack 22A, the second high voltage terminal 58B of the second cell stack 22B, and a mechanical fastener 70 joining the first high voltage terminal 58A to the second high voltage terminal 58B. The second high voltage terminal 58B may have the same polarity (e.g., for a parallel string configuration) or a different polarity (e.g., for a series string configuration) than the first high voltage terminal 58A.

The first high voltage terminal 58A may be connected to a first cross member beam 38A of the first cell stack 22A and the second high voltage terminal 58B may be connected to a second cross member beam 38B of the second cell stack 22B. The first and second cross member beams 38A, 38B may establish one of the cross member assemblies 40 of the traction battery pack 18.

The first and second cell stacks 22A, 22B may be positioned adjacent to one another within the traction battery pack 18 such that the first electrical contact portion 68A of the first high voltage terminal 58A and the second electrical contact portion 68B of the second high voltage terminal are arranged side-by-side with respect to one another along the axis 72. In one embodiment, axis 72 is a vertical axis (see fig. 5). In another embodiment, the axis 72 is a horizontal axis that may extend parallel to the vehicle transverse direction (see fig. 6).

The first electrical contact portion 68A may include a first aperture 80A and the second electrical contact portion 68B may include a second aperture 80B. When the first and second cell stacks 22A, 22B are positioned adjacent to one another, the first and second holes 80A, 80B may be coaxially aligned along the axis 72.

The mechanical fastener 70 may be received through the first and second apertures 80A, 80B to engage the first and second electrical contact portions 68A, 68B. In one embodiment, the mechanical fastener 70 is a bolt and nut assembly. However, other mechanical fasteners (including, for example, welds) may be used to engage the first electrical contact portion 68A and the second electrical contact portion 68B.

After positioning the first and second cell stacks 22A, 22B into the housing assembly 24, the first electrical contact portion 68A may be joined to the second electrical contact portion 68B. Proper alignment of the first electrical contact portion 68A with the second electrical contact portion 68B may facilitate reliable assembly of the electrical connector system 64.

Fig. 7A and 7B illustrate another electrical connection system 164 for electrically connecting a first cell stack 22A and an adjacent second cell stack 22B of the traction battery pack 18. The electrical connection system 164 may be established by the first high voltage terminal 158A of the first cell stack 22A and the second high voltage terminal 158B of the second cell stack 22B. Fig. 7A shows the electrical connection system 164 before the first and second high voltage terminals 158A, 158B are joined, and fig. 7B shows the electrical connection system 164 after the first and second high voltage terminals 158A, 158B are joined.

In this embodiment, the electrical connection system 164 may provide a male design in which the first electrical contact portion 168A of the first high voltage terminal 158A is configured as a male portion that may be inserted into a female portion provided by the second electrical contact portion 168B of the second high voltage terminal 158B. The first electrical contact portion 168A may engage the second electrical contact portion 168B when the first cell stack 22A is moved into position relative to the second cell stack 22B.

The second electrical contact portion 168B may include a pair of spaced apart arms 90. Slots 92 may extend between the spaced apart arms 90. The slot 92 provides open space for receiving the first electrical contact portion 168A to establish the electrical connection system 164.

Each of the spaced apart arms 90 may include an outer coating 94. The outer coating 94 may protect portions of the electrical connection system 164 during and after assembly.

Fig. 8 illustrates yet another electrical connection system 264 for electrically connecting a first cell stack 22A and an adjacent second cell stack 22B of the traction battery pack 18. The electrical connection system 264 may be established by the first high voltage terminal 258A of the first cell stack 22A, the second high voltage terminal 258B of the second cell stack 22B, the bus bar 96, and the mechanical fastener 98 connecting the bus bar 96 to the first high voltage terminal 258A and the second high voltage terminal 258B.

The first high voltage terminal 258A may be connected to a first cell tab terminal 262A of the first cell stack 22A and the second high voltage terminal 258B may be connected to a second cell tab terminal 262B of the second cell stack 22B. The weld bead 97 may be used to connect the first high voltage terminal 258A to the first cell tab terminal 262A and the second high voltage terminal 258B to the second cell tab terminal 262B.

The first high voltage terminal 258A may include a first electrical contact portion 268A and the second high voltage terminal 258B may include a second electrical contact portion 268B. The first electrical contact portion 268A and the second electrical contact portion 268B may be disposed adjacent to each other at a position vertically above the first cross-member beam 38A of the first cell stack 22A and the second cross-member beam 38B of the second cell stack 22B. The first and second cross member beams 38A, 38B may together establish a cross member assembly 40 of the traction battery pack 18.

The first electrical contact portion 268A and the second electrical contact portion 268B may establish a relatively flat interface 99 to receive the bus bar 96 thereon. The bus bar 96 may be secured to each of the first electrical contact portion 268A and the second electrical contact portion 268B by mechanical fasteners 98.

The electrical connection system of the present disclosure is capable of reliably connecting the battery cell stacks of the traction battery pack. The electrical connection system allows for various embodiments including vertical stacking connections, horizontal stacking connections, plug-in connections, bus bar independent connections, bus bar dependent connections, and the like.

Although various non-limiting embodiments are shown with specific components or steps, embodiments of the present disclosure are not limited to these specific combinations. It is possible to use some of the features or components from any one of the non-limiting embodiments in combination with features or components from any one of the other non-limiting embodiments.

It should be understood that the same reference numerals indicate corresponding or similar elements throughout the several views. It should be understood that while particular component arrangements are disclosed and illustrated in the exemplary embodiments, other arrangements may benefit from the teachings of this disclosure.

The above description should be construed as illustrative and not in any limiting sense. A worker of ordinary skill in this art would recognize that certain modifications would come within the scope of this disclosure. For these reasons, the following claims should be studied to determine the true scope and content of this disclosure.

Claims (15)

1. A traction battery pack, comprising:

a first cell stack including a first cross member beam;

a first high voltage terminal mounted to the first cross member beam;

a second cell stack including a second cross-member beam; and

a second high voltage terminal mounted to the second cross member beam,

wherein the first high voltage terminal is coupled to the second high voltage terminal to electrically connect the first cell stack and the second cell stack.

2. The traction battery pack of claim 1, wherein a mechanical fastener couples the first high voltage terminal to the second high voltage terminal.

3. The traction battery pack of claim 2, wherein the first high voltage terminal includes a first electrical contact portion and the second high voltage terminal includes a second electrical contact portion disposed alongside the first electrical contact portion along a vertical or horizontal axis, and further wherein the mechanical fastener extends along the vertical or horizontal axis to couple the first high voltage terminal to the second high voltage terminal.

4. The traction battery pack of any preceding claim, wherein a weld couples the first high voltage terminal to the second high voltage terminal.

5. The traction battery pack of any preceding claim, wherein a bus bar couples the first high voltage terminal to the second high voltage terminal.

6. The traction battery pack of any preceding claim, wherein the first high voltage terminal comprises a male portion configured to engage a female portion of the second high voltage terminal to electrically connect the first cell stack and the second cell stack, and optionally wherein the female portion comprises a first arm, a second arm, and a slot extending between the first arm and the second arm, and further wherein the male portion is received within the slot to electrically connect the first cell stack and the second cell stack.

7. The traction battery pack of any preceding claim, wherein the first and second cross-member beams establish a cross-member assembly disposed between the first and second cell stacks of the traction battery pack.

8. The traction battery pack of claim 7, comprising a vent channel disposed between the first and second cross-member beams, and optionally wherein a housing cover provides a vertically upper side of the vent channel and a housing tray or heat exchanger plate provides a vertically lower side of the vent channel, and further optionally wherein a vent opening formed through the first cross-member beam establishes a vent path between the first cell stack and the vent channel.

9. The traction battery pack of any preceding claim, wherein the first cell stack comprises a plurality of battery cells supported between the first and third cross-member beams, and the second cell stack comprises a further plurality of battery cells supported between the second and fourth cross-member beams.

10. The traction battery pack of any preceding claim, wherein the first high voltage terminal includes a base mounted to the first cross member beam and an electrical contact portion extending away from the base at a lateral angle.

11. The traction battery pack of any preceding claim, wherein the first high voltage terminal includes a first electrical contact portion having a first aperture and the second high voltage terminal includes a second electrical contact portion having a second aperture coaxially aligned with the first aperture.

12. A traction battery pack, comprising:

a first cell stack;

a second cell stack;

a cross member assembly disposed between the first cell stack and the second cell stack; and

an electrical connection system for electrically connecting the first cell stack and the second cell stack,

wherein the electrical connection system includes a first high voltage terminal of the first cell stack, a second high voltage terminal of the second cell stack, and a mechanical fastener joining the first high voltage terminal to the second high voltage terminal.

13. The traction battery pack of claim 12, wherein the mechanical fastener comprises a weld bead, and optionally wherein the weld bead joins a busbar to the first high voltage terminal and the second high voltage terminal.

14. The traction battery pack of claim 12 or 13, wherein the mechanical fastener comprises a bolt and nut assembly.

15. The traction battery pack of any one of claims 12-14, wherein the first high voltage terminal is mounted to a first cross member beam of the cross member assembly and the second high voltage terminal is mounted to a second cross member beam of the cross member assembly.