BATTERY PACKS FOR UTILITY VEHICLE ELECTRIC DRIVETRAINS

A battery assembly is provided for an electric vehicle that include a housing, one or more battery units, and a connector. The housing has a forward side, a rearward side, a bottom side, and a top portion. The top portion is configured to project into a space between adjacent frame rails. The housing also has a lateral portion configured to extend under a bottom surface of one of the adjacent frame rails. The one or more battery units are disposed within the top portion of the housing. The connector disposed over the lateral portion of the housing. The connector being configured to releasably coupled with one of the adjacent frame rails.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

BACKGROUND

Field of the Invention

This application is directed to battery packs or modules powering electric motors to propel vehicles, in particular for trucks and other utility vehicles of various types.

Description of the Related Art

Electric vehicles have become more and more popular in recent years. This is particularly true among passenger vehicles. The use of electric motors and batteries to propel heavy and medium duty utility vehicles has been much less prevalent. Equipping utility vehicles such as these with well-designed electric drivetrains presents unique complexities.

SUMMARY

There is a need for improved battery packs that can power utility vehicles with sufficient power storage while being applicable to stock vehicles. There is a need for battery assemblies that provide enhanced or greater storage while occupying a minimum of area best reserved for other vehicle equipment, such as a truck box, a beverage body, or other assemblies that may overhang a frame assembly or other chassis portion. Such battery assemblies preferably are transversely compact, e.g., by being substantially entirely disposed within the width of a frame assembly, at least at or just below the point of connection to the frame assembly.

In one example, a battery assembly for an electric vehicle is provided that include a housing, one or more battery units, and a connector. The housing has a forward side, a rearward side, a bottom side, and a top portion. The top portion is configured to project into a space between adjacent frame rails. The housing also has a lateral portion configured to extend under a bottom surface of one of the adjacent frame rails. The one or more battery units are disposed within the top portion of the housing. The connector is coupled with the housing. In one example, the connector is disposed over the lateral portion of the housing. The connector is configured to be releasably coupled with one of the adjacent frame rails.

In another example, a battery assembly for an electric vehicle is provided that includes a housing, one or more battery units, and a mounting system. The housing has a concave enclosure that has a forward side, a rearward side, a top portion and a bottom side. An access plate is coupled with the bottom side. The top portion has a first shoulder and a second shoulder. The first shoulder extends from a first lateral side of the concave enclosure toward a central portion of the concave enclosure. The first shoulder extends a first distance from the access plate (e.g., perpendicular to the access plate). The second shoulder extends from a second lateral side of the concave enclosure toward the central portion. The second shoulder extends a second distance perpendicular from the access plate (e.g., perpendicular to the access plate). The central portion extends from the first shoulder to the second shoulder. The central portion extends a third distance from the access plate (e.g., perpendicular to the access plate). The third distance is greater than the first distance and the second distance. The one or more battery units are disposed within the concave enclosure at an elevation above the first shoulder and an elevation above the second shoulder. The mounting system has a first portion disposed on the first shoulder and a second portion disposed on the second shoulder. The mounting system has a frame member bracket and a shoulder bracket system. The frame member bracket is configured to connect to a frame member of a vehicle. The shoulder bracket system has a load member, an aperture array and a vibration isolator. The load member has a first portion disposed over the first shoulder of the top portion of the concave enclosure and a second portion angled relative to the first portion. The second portion is disposed along a lateral side of the central portion. The aperture array is disposed along the first lateral side of the concave enclosure, e.g., at an outer edge of the first shoulder. The aperture array is configured to be coupled to the frame member bracket. The vibration isolator is disposed between the load member and a top surface of the first shoulder. The vibration isolator reduces load transmission from the frame member of the vehicle to the housing.

In one variation, the first and second distance are approximately the same. In another variation, the third distance is more than twice the first distance.

The battery assembly can have a relatively high aspect ratio, while being configured to be mounted below a vehicle frame assembly. In various configurations, an aspect ratio of the housing can exceed 0.5. The aspect ratio can be defined as a ratio of the third distance to a width defined in a horizontal plane perpendicular to the third distance and perpendicular to a longitudinal axis of a vehicle to which the battery assembly is configured to be coupled.

The battery assemblies disclosed herein can have a battery management module disposed on one of the forward side and the rearward side of the housing. The battery management module can be low profile, e.g., configured to extend under an element of a chassis, e.g., under a cross member disposed between adjacent frame rails.

In some cases, the aperture array can be disposed on a lateral extension of the load member. The lateral extension can include a connection portion coupling the first portion of the load member to the second portion of the load member. The lateral extension can include a frame member clearance portion disposed between the connection portion and the aperture array. The frame member clearance portion can enable a bottom portion of a frame member to at least partially be nested in the load member.

In some embodiments, the load member can include an elevated portion disposed between a first compressible member of the vibration isolator and a second compressible member of the vibration isolator. The elevated portion transferring a connection load to the first portion of the load member.

In another embodiment, a vehicle assembly is provided that includes a frame assembly and a battery assembly. The frame assembly includes a first frame rail that has an inner surface facing toward a central longitudinal axis of the frame assembly and an outer surface facing away from the central longitudinal axis of the frame assembly. The frame assembly further includes a second frame rail disposed on an opposite side of a central longitudinal axis of the frame assembly from the first frame rail. The second frame rail has an inner surface facing toward the central longitudinal axis of the frame assembly and an outer surface facing away from the central longitudinal axis of the frame assembly. The battery assembly has a housing, a first battery unit, a second battery unit, and a mounting system. The housing has a concave enclosure that has a central portion disposed between and projecting from adjacent shoulder portions. The first battery unit is disposed within the central portion. The second battery unit is disposed within one of the shoulder portions. The mounting system has a first frame member bracket, a second frame member bracket, and a shoulder bracket system. The first frame member bracket is coupled to the outer surface of the first frame rail. The second frame member bracket is coupled to the outer surface of the second frame rail. The shoulder bracket system has a first load member, a vibration isolator, and a first aperture array. The first load member has a first portion disposed over one of the adjacent shoulder portions and a second portion disposed along the central portion of the housing. The vibration isolator is disposed between the first load member and a top surface of the one of the adjacent shoulder portions. The first aperture array is disposed at or adjacent to a first lateral edge of the housing. The first aperture array is coupled with the first frame member bracket. The shoulder bracket assembly includes a second load member and a second aperture array. The second load member has a first portion disposed over the other of the adjacent shoulder portions and a second portion disposed along the central portion of the housing. A vibration isolator is disposed between the second load member and a top surface of the other of the adjacent shoulder portions. The second aperture array is disposed at or adjacent to a second lateral edge of the housing. The second aperture array is coupled with the second frame member bracket. The first battery unit is disposed between the first frame rail and the second frame rail. The second battery unit is disposed below the first frame rail and the second frame rail.

In one or more variations, the first lateral edge of the housing is disposed inboard of the outer surface of the first frame rail and the second lateral edge of the housing is disposed inboard of the outer surface of the second frame rail. Vehicle equipment is or are mounted to the first frame rail and/or the second frame rail at the same position along the longitudinal axis of the vehicle assembly as is the battery assembly. The frame assembly can include a first cross member coupling the first frame rail to the second frame rail and a second cross member coupling the first frame rail to the second frame rail. The first cross member is disposed forward of the second cross member. The battery assembly is disposed between the first cross-member and the second cross-member. In one vehicle assembly, a second battery assembly is coupled with the frame assembly forward of the first cross-member and between the inner surface of the first frame rail and the inner surface of the second frame rail. In a further variation, an axle drive assembly is coupled with the frame assembly rearward of the second cross-member and between the inner surface of the first frame rail and the inner surface of the second frame rail. In some vehicle assemblies, an accessory module is electrically coupled to the battery assembly and an axle drive assembly is coupled with the battery assembly. The accessory module and the axle drive assembly are powered by the same battery assembly.

Vehicle assemblies can be provided in which a power distribution assembly is disposed electrically between two or more of the battery assembly, the axle drive assembly, and the accessory module. A range extender module can be electrically coupled with the power distribution assembly. The range extender module can include a fuel cell.

In various vehicle assemblies, an aspect ratio can be defined as a ratio of a height of the housing of the battery assembly in a vertical direction to a width of the housing of the battery assembly in a horizontal direction transverse to the central longitudinal axis of the frame assembly exceeds 0.5.

DETAILED DESCRIPTION

While the present description sets forth specific details of various embodiments, it will be appreciated that the description is illustrative only and should not be construed in any way as limiting. Furthermore, various applications of such embodiments and modifications thereto, which may occur to those who are skilled in the art, are also encompassed by the general concepts described herein. Each and every feature described herein, and each and every combination of two or more of such features, is included within the scope of the present invention provided that the features included in such a combination are not mutually inconsistent.

This application discloses advantageous battery pack configurations with transversely compact configurations, but which still have sufficient capacity to power utility vehicles, such as box trucks, refrigerator trucks and other Class 5 and 6 trucks, as well as vehicles of other sizes and configurations.

FIG.1shows a vehicle assembly50that includes a cab52disposed adjacent to, e.g., above and in some cases extending ahead of a front end compartment54. The cab52also can be supported by a frame assembly56including frame rails58, e.g., a frame rail58A and a frame rail58B. The frame assembly56also can support an axle62. The axle62is rotatably supported and also supports wheels to drive the vehicle assembly50during operation thereof. The vehicle assembly50can be a stock vehicle. The vehicle assembly50can be one that was initially designed for or can be alternatively incorporated into a vehicle with an internal combustion engine. The vehicle assembly50can be modified to include an electric drivetrain system98. The electric drivetrain system98is described below separate from the vehicle assembly50in connection withFIGS.5-5A.

The frame assembly56also can include one or more cross members60that connect the frame rail58A to the frame rail58B. The cross members60can be disposed forward and rearward of the axle62. The cross members60can be positioned between front and rear wheels of the vehicle assembly50. The cross members60can separate the frame assembly56into two, three, four, five, six or more than six sections separating different components of the electric drivetrain system98. The cross members60can be mounted toward the top of the frame rails58A,58B leaving some clearance for components of the battery assembly100as shown inFIG.6.

The electric drivetrain system98can include one or more, e.g., two battery assemblies100. The battery assembly100is a source of electrical power of the vehicle assembly50that can support operation of one or more loads thereof. The electric drivetrain system98can include an axle drive assembly112as one example of a load to be powered by the battery assembly100. The axle drive assembly112can be directly coupled to the axle62, as shown inFIG.3. The electric drivetrain system98can include a front end accessory component assembly104as another example of a load to be powered by the battery assembly100. In various examples, the battery assembly100powers the front end accessory component assembly104and the axle drive assembly112concurrently. The electric drivetrain system98can be controlled by a power distribution assembly108that can be mounted in any convenient location on the vehicle assembly50, e.g., in any available space between the frame rail58A and the frame rail58B. The power distribution assembly108can be mounted behind the axle62. The power distribution assembly108can be mounted forward of the axle drive assembly112in one variation. The electric drivetrain system98can include an electric motor that is mounted away from, e.g., forward of, the axle62. In such embodiments, the electric motor can rotate a transmission shaft to indirectly rotate the axle62.

FIG.5Ashows one way of controlling the flow of electrical power in the electric drivetrain system98. The battery assembly100can include one or more than one assembly of battery cells, e.g., a first battery cell assembly100A and a second battery cell assembly100B. The first battery cell assembly100A and the second battery cell assembly100B can be coupled independently to the power distribution assembly108via dedicated high voltage cables HV1. The power distribution assembly108can include a power distribution unit120configured to couple with the high voltage cables HV1at a cable junction thereof. The power distribution unit120includes circuits (e.g., fuses, contactors, and controllers) to control the flow of current between the battery units of the battery assembly100and loads of the electric drivetrain system98. The power distribution unit120outputs current via a high voltage cable HV2to an inverter124. The inverter124is configured to change the high voltage DC current flowing through the high voltage cables HV2to three phase high voltage power in the high voltage cables HV4. Three phase high voltage power is used by the axle drive assembly112to propel the vehicle assembly50. Thus, the inverter124outputs three phase high voltage current via high voltage cable HV4to the axle drive assembly112. The operation of the axle drive assembly112is controlled by a powertrain control circuit128disposed in the power distribution assembly108. The power distribution unit120is coupled with a range extender module132, which can include a fuel cell, additional batteries or other components to generate current to be used to recharge the battery assembly100. The range extender module132can be disposed in the power distribution assembly108or in a separate location on the vehicle assembly50.

The electric drivetrain system98can include a charge receptacle116. The charge receptacle116can be connected to a high voltage DC power supply to direct current to the power distribution unit120and thereby to the battery assembly100or battery assemblies100. The charge receptacle116can include a low voltage AC power connection. The power distribution assembly108can include (either in the power distribution unit120or in a separate component) a charge circuit configured to intake AC power and to generate DC power to charge the first battery cell assembly100A and/or the second battery cell assembly100B.

One or more components of the electric drivetrain system98can be operated by a vehicle control unit180, which can be used to control the operation of the axle drive assembly112, the power distribution unit120, the inverter124, powertrain control circuit128, the range extender module132, and/or other electrical components of the electric drivetrain system98. The vehicle control unit180also can control components on the front end accessory component assembly104in various configurations. The vehicle control unit180can be coupled with the front end accessory component assembly104directly or by way of the power distribution unit120. The front end accessory component assembly104can be coupled with the battery assembly100by way of the power distribution assembly108, e.g., by way of the power distribution unit120. High voltage cables HV3can be coupled with and between the power distribution unit120and the front end accessory component assembly104. The front end accessory component assembly104also could be directly connected to the battery assembly100in some embodiments.

The front end accessory component assembly104can include coolant pumps and loops, air compressors, inverters for low voltage operation, and other components to facilitate connecting components of multiple vehicle subsystems to the frame assembly56of the vehicle assembly50at one location and as a unit. Additional aspects of the front end accessory component assembly104are described in PCT/US2020/028859, which published as WO2020/215023, and which is incorporated by reference herein in its entirety to supplement the disclosure of the front end accessory component assembly104, to supplement the disclosure of routing and protecting high voltage cables, and to supplement variations on the power distribution assembly108, and for all other purposes as well. The power distribution assembly108can have any of the configurations disclosed in US63/260,601 (applicant's docket number HEX.023PR, titled POWER DISTRIBUTION MODULES FOR ELECTRIC DRIVETRAINS, which is incorporated by reference herein in its entirety).

FIG.6shows some details of the connection of the battery assembly100and the connection thereof to the frame assembly56, e.g., to the frame rail58A and the frame rail58B. In one embodiment, a forward section of the frame assembly56includes a forward cross member60and a portion of the span of the frame rail58A and the frame rail58B (collectively the frame rails58). The forward section can be located immediately rearward of the front end compartment54, where the front end accessory component assembly104can be mounted. The forward section can include an available space between the frame rails58. The frame assembly56is sufficiently rigid without additional supports between the frame rails58such that a space is available to accommodate a portion of the battery assembly100. The battery assembly100can have a generally inverted-T shape, as discussed further below. A central portion490of a housing400of the battery assembly100can be positioned between the frame rails58, as seen inFIG.6. The battery assembly100can be supported by frame member brackets408on an outward facing side of the frame rails58. A lower portion of the battery assembly100can include lateral portions that extend to but generally not outward of the outward facing sides of the frame rails58. As discussed further below, this configuration locates the battery assembly100generally between the outward facing sides of the frame rail58A and the frame rail58B. In some cases, the battery assembly100includes a concave enclosure450and an access plate470. At least an upper portion of, and in some cases the entirety of, the concave enclosure450will have a maximum width not exceeding the distance between the outward facing sides of the frame rails58. The access plate470may be part of an assembly at the bottom of the battery assembly100that may extend outward of the frame rails58. However, the portions of the battery assembly100near the frame assembly56are kept low profile to leave an area for other vehicle equipment unobstructed. The battery assembly100can be configured such that the battery assembly100does not extend into adjacent spaces of the vehicle assembly50where other vehicle equipment may be located or may need to be positioned.FIG.6thus shows that the battery assembly100provides ample volume for battery units without impairing the ability of the vehicle assembly50to accommodate such equipment along outer edges of the frame assembly56.

As discussed more fully below, the frame member brackets408can form part of a mounting system404that includes components coupled with a top portion of the housing400of the battery assembly100. The mounting system404can include components that couple with a top surface of the housing400outward of the central portion490, e.g., with a first lateral side486, a second lateral side502or of both lateral sides of the housing400.

FIGS.7A-7Dshow the battery assembly100in more detail. The battery assembly100includes a housing400that has a shoulder bracket system412. The shoulder bracket system412when combined with the frame member brackets408can form the mounting system404in various examples. The battery assembly100can employ four (or more) frame member brackets408. A first frame member bracket408A can be disposed on a forward, driver side of the battery assembly100when the battery assembly100is attached to a vehicle. A second frame member bracket408B can be disposed on a forward, rider side of the battery assembly100when the battery assembly100is attached to a vehicle.FIG.7Ashows that a third frame member bracket408can be disposed on driver side of the battery assembly100and the fourth frame member bracket408can be disposed on a rider side of the vehicle when the battery assembly100is attached to a vehicle. The frame member brackets408and the shoulder bracket system412enable the housing400to be secured to the vehicle in a low profile manner as described further below.

FIGS.7A and7Dshow that the housing400can include a concave enclosure450and the access plate470. The concave enclosure450and the access plate470can fully enclose a volume that is used to contain battery units514(seeFIG.7C). The battery units514can be self-contained battery cells or self-contained arrays of battery cells. A plurality of such cells or units can be combined to provide the first battery cell assembly100A or the second battery cell assembly100B.FIG.7Dshows that the enclosed volume can be greater in a central area as discussed further below. The housing400can include a forward side454, a rearward side458, a top portion462and a bottom side466. The forward side454can be generally flat. However, one or more coolant ports456(seeFIG.7B) can be provided on the forward side454. The rearward side458can include a battery management module518section projecting therefrom. The rearward side458can include a coolant port460disposed thereon. The coolant port460can be disposed on an upper portion of the rearward side458. The battery management module518can be disposed on a lower portion of the rearward side458. The battery management module518can include electronic components or electronics used to control the flow of current to and from the first battery cell assembly100A and the second battery cell assembly100B, and can control how and when energy stores are drawn from each assembly.FIG.7Dshows that the battery management module518can be at least partially disposed in a volume that is continuous with and not divided from an area provided for enclosing the battery units514.

The access plate470can be removable from the top portion462at the bottom side466to provide access to the enclosed volume. This can be done without removing the battery assembly100from the vehicle assembly50, if desired. Such access can be for purposes of servicing and replacing the battery units514. The top portion462can extend from a top surface of the housing400down to the bottom side466. The top portion462can include side surfaces that extend from a first upper surface, e.g., a top surface, of the top portion462to the bottom side466. The side surfaces can include two vertical portions, an upper vertical portion and a lower vertical portion. These vertical portions can be spaced apart horizontally by a second upper surface. The second upper surface can be disposed at a lower elevation than the first upper surface. In one example, a first lateral portion of the housing400can form a first shoulder482of the battery assembly100. Also, a second lateral portion of the housing400can form a second shoulder498of the battery assembly100.

When viewed from the front or the back, the housing400has a first shoulder482, a second shoulder498, and a central portion490between outer lateral sides of the housing400, e.g., of the concave enclosure450of the housing400. The first shoulder482can extend horizontally between a top surface of the central portion490and a first lateral side486of the housing400. The second shoulder498can extend horizontally between the top surface of the central portion490and the second lateral side502. The first shoulder482and the second shoulder498provide low profile lateral portions that facilitate the battery assembly100being underslung, e.g., mountable to and extending beneath the frame rails of a vehicle. The low profile lateral portions also allow the shoulder bracket system412to be positioned at least partially under the frame rails. The first shoulder482defines a first distance494between the access plate470and a top surface484of the first shoulder482. The second shoulder498defines a second distance506disposed between the access plate470and a top surface of the second shoulder498. The central portion490defines a third distance510between the access plate470and the top surface of the central portion490. The first distance494, the second distance506and the third distance510each extend perpendicularly to the access plate470. The third distance510is more than the first distance494. The third distance510is more than the second distance506. The first distance494and the second distance506can be substantially equal to each other. In other embodiments, the first distance494and the second distance506are different. The specific values of the first distance494and the second distance may be based on numerous factors, including geometry of other aspects of the vehicle or the presence of other components of the vehicle. The third distance510can be more than, e.g., double or more than double the first distance494. The third distance510can be more than, e.g., double or more than double the second distance506.

The third distance510can correspond to the overall height (e.g., the largest vertical dimension) of the battery assembly100. In some embodiments, the battery assembly100has a high aspect ratio, e.g., a high ratio of the third distance510to the width W of the housing400. The aspect ratio can be greater than 0.5 in some embodiments, in other embodiments the aspect ratio can be greater than 0.25, 0.75, 1.0 or any range having any of the foregoing ratios as end points.

FIG.7Cshows that the third distance510, which corresponds to a depth of the concave space of the concave enclosure450can enable a number of battery units514to be disposed at a higher elevation than the highest elevation of any of the battery units514disposed within the housing400beneath the first shoulder482or beneath the second shoulder498. A battery stack disposed in the central portion490can have more than twice as many battery units514than a corresponding stack of battery units514between the central portion490and the first lateral side486(e.g., beneath first shoulder482) and/or between the central portion490and the second lateral side502(e.g., beneath the second shoulder498). A portion of the central portion490that is at an elevation higher than the top surface484of the first shoulder482or the second shoulder498can be configured to house more battery units514than can be housed beneath either the first shoulder482or the second shoulder498.

FIGS.7A and7Bshow features of the shoulder bracket system412.FIG.7Bshows the frame member brackets408separated from the shoulder bracket system412. The shoulder bracket system412includes a load member530. The load member530can form part of a connector to connect the battery assembly100to the frame assembly56of the vehicle assembly50. The load member530includes a first portion532and a second portion534. The first portion532is disposed over the first shoulder482, e.g., spaced apart from and/or in contact with the top surface484of the first shoulder482. The second portion534can be angled relative to the first portion532. The second portion534can be disposed at a ninety degree angle to the first portion532. The second portion534can be disposed along the lateral side492, e.g., spaced from and/or in contact with, of the central portion490.FIG.7Cshows that the second portion534can be spaced apart from the lateral side492by a small distance. In some embodiments, the second portion534can be connected to the lateral side492. The load member530can extend the entire length of the housing400from the forward side454to the rearward side458. The load member530can extend from the lateral side492to the lateral side of the housing400.FIG.8shows that in one example one load member530covers the entire first shoulder482and one load member530covers the entire second shoulder498.

The housing400can be supported in other ways. For example, a bracket system including a modified frame member bracket408can be coupled with another side or surface of the housing400as shown in connection with a battery assembly100B as shown inFIG.9. A load member similar to the load member530discussed in connection with the battery assembly100) can be mounted to the first lateral side486of the battery assembly100A. A load member530can be mounted to the second lateral side502of the battery assembly100A. A load member530can be mounted to a top of the central portion490of the battery assembly100A. In some cases, the width W of the housing400can be less and a vibration isolator546can be mounted between the frame assembly56of the vehicle assembly50, e.g., the frame rail58A, and a side surface of the housing400B, e.g., the first lateral side486or another surface of the housing400as shown in connection with the battery assembly100B ofFIG.10. The battery assembly100B may be a narrower configuration, e.g., having a housing400B with a smaller width W. The battery assembly100B can be mounted with a frame member bracket408B having a transverse projection allowing the connection portion of the frame member bracket408B to be outward of the outer surface of the housing400B.

Connection of the frame member bracket408to the load member530can be achieved in any suitable manner In one embodiment the shoulder bracket system412includes an aperture array542disposed at a lateral edge thereof. The aperture array542can be disposed on a lateral extension544of the load member530. The aperture array542can be coupled with the frame member bracket408to secure the battery assembly100to the frame assembly56. The lateral extension544can comprise a U-shaped member coupled with a top surface of the first portion532and with an outward facing side of the second portion534.

The shoulder bracket system412incorporates a vibration isolator546to reduce the effect of vibration or impact from the road to the vehicle assembly50applied to or on the battery assembly100. The vibration isolator546can be integrated into the connection of the shoulder bracket system412to the housing400. The vibration isolator546can be disposed between the first portion532of the load member530and the top surface484of the first shoulder482of the housing400.FIG.8Ashows that the vibration isolator546can have a first compressible member546A disposed between an elevated portion570of the first portion532and the top surface484of the first shoulder482of the housing400. The first compressible member546A can have a first side contacting the top surface484and a second side contacting a bottom surface of the elevated portion570. The vibration isolator546can have a second compressible member546B disposed between the elevated portion570and a fastener assembly574. The fastener assembly574can include a compression disk578disposed over and in contact with a top surface of the second compressible member546B.

Tightening of a bolt disposed through the vibration isolator546and through one of a plurality of fastening holes582in the housing400causes securing of the shoulder bracket system412to the top surface484. Such securing may be accomplished without the load member530contacting the top surface484in some embodiments. The shoulder bracket system412can be secured to the housing400while maintaining a gap between the first portion532and the top surface484and between the second portion534and the lateral side492of the central portion490. In some variations, the only point of contact between the shoulder bracket system412and the housing400is the fastener assembly574and the vibration isolator546.

The load member530can be made stiffer by providing a connection portion564disposed between and connecting the first portion532to the second portion534. The connection portion564can be disposed at a ninety degree angle to the first portion532. The connection portion564can be disposed at a ninety degree angle to the second portion534. The connection portion564can be disposed at a ninety degree angle to the first portion532and to the second portion534. In one embodiment, the connection portion564extends from the second portion534to the aperture array542at a first location and from the aperture array542to the second portion534at a second location rearward of the first location. The connection portion564can have a U-shaped configuration as viewed from the top. The connection portion564can be tapered vertically or in elevation outwardly or laterally such that the outer portion thereof comprises a clearance portion566. The clearance portion566has a lower profile, e.g., a lower elevation, than the connection portion564disposed inward thereof. The clearance portion566provides additional space of the frame rail58A to be nested into the area above the first shoulder482. The clearance portion566allows the central portion490to extend higher into the central area of the frame assembly56. When the frame rail58A is nested into the clearance portion566, the inner surface59A of the frame rail58A faces in a direction toward a central vertical plane CP or central longitudinal axis of the frame assembly56and the outer surface59B face away therefrom. The inner surface59A can face the lateral side492of the central portion490when so nested. The outer surface59B can be coupled to the inner surface of the frame member bracket408. As a result, the battery assembly100is substantially retained inward of the frame rail58A, or between the frame rail58A and the frame rail58B. This configuration allows a vehicle equipment area586to be maintained open. The vehicle equipment area586can be free of any portion of the battery assembly100.FIG.3shows the vehicle assembly50equipped with the battery assembly100having the vehicle equipment area586substantially unobstructed by the battery assembly100.FIG.3shows that the vehicle equipment area586can be provided on both sides of the vehicle assembly50because the battery assembly100is fully supported between the outer surface of the frame rail58A and the outer surface of the frame rail58B.

By preserving the vehicle equipment area586, the battery assembly100can facilitate mounting other vehicle equipment in the space provided. For example, downward hanging portions of a truck box or beverage body can extend into the vehicle equipment area586without obstruction from the battery assembly100. Because the central portion490extends into the space between the frame rails58a large amount of battery storage is still possible. For applications requiring more storage, additional (e.g., second, third or more than three) battery assemblies100can be provided on the frame rails58. The battery assembly100also provides a low profile battery management module518. The battery management module518can be disposed at or below the elevation of the first shoulder482or second shoulder498such that the battery management module518can nest under a cross members60while still allowing the central portion490of the housing400to extend up toward and even to or in some cases over the top edge of the frame rails58.

The battery assembly100thus provides a transversely compact assembly that enhances volume for storage of battery units514within a central area to accommodate large stacks of battery units inward of the inward facing sides of frame rails58. As such, utility vehicles such as Class 5 and 6 trucks and other similar vehicles can be equipped to operate by the electric drivetrain system98.