Abstract: Bus bar routing configurations are provided for traction battery packs. Exemplary routing configurations may position the bus bar over top of one or more cells stacks of the traction battery pack. A structural cross-member beam of each cell stack may include a notch for accommodating the bus bar. The bus bar may therefore be conveniently nested within the cross-member beam without increasing the vertical or “z-axis” footprint of the traction battery pack.

Abstract: Structural cross-member assemblies are provided for use within traction battery packs. An exemplary traction battery pack may include a cell stack including a plurality of battery cells arranged between a first cross-member assembly and a second cross-member assembly. Each cross-member assembly of the cell stack may include a ladder frame and one or more reinforcement beams mounted to the ladder frame. Each reinforcement beam may be a pultrusion. The pultrusion may be configured to enable the cross-member assembly to react against both tensile loads and compressive loads that act on the cell stack.

Abstract: A battery pack assembly includes a cross-member assembly extending along a cross-member axis, and a battery array alongside the cross-member assembly. The battery array has at least one group of battery cells and an depopulated area disposed along a battery array axis. A first group of battery cells can be spaced a distance along the battery array axis from a second group of battery cells to provide the depopulated area. A first group of battery cells can be spaced from an endplate of an array to provide the depopulated area.

Abstract: A method of assembling a battery pack includes positioning one or more terminals of a cell stack within a slot that is provided by a frame of a cross-member assembly. The method further includes securing a beam of the cross-member assembly to the frame after the positioning. The beam can be a pultruded beam that covers several slots of the frame.

Abstract: Structural thermal barrier assemblies are provided for traction battery packs. An exemplary structural thermal barrier assembly may be configured to both inhibit the transfer of thermal energy inside the traction battery pack and to increase the structural integrity of the traction battery pack. In some implementations, the structural thermal barrier assembly may establish a basin for receiving an adhesive. In other implementations, the structural thermal barrier assembly may include a pultruded thermal barrier fin.

Abstract: Thermal barrier shields are provided for traction battery packs. The thermal barrier shield may be arranged to inhibit the transfer of thermal energy from a cell packet of a cell stack to an enclosure cover of the traction battery pack. The cell packet may be arranged between a first structural thermal barrier assembly and a second structural thermal barrier assembly of the cell stack. The thermal barrier shield may be supported at a position between the enclosure cover and the cell packet by the first structural thermal barrier assembly and the second structural thermal barrier assembly.

Abstract: A battery pack system includes a battery pack enclosure housing a battery array, and a barrier assembly within the enclosure. The barrier assembly includes a container and an expandable foam contained within the container. A battery pack barrier providing method, includes positioning a container within an interior of a battery pack enclosure adjacent to at least one component within the interior, introducing an expandable foam into the container, and delivering the expandable foam through the container to at least one interface between the container and the at least one component.

Abstract: Battery cell stack designs are provided for traction battery packs. An exemplary cell stack may include a thermal barrier assembly that is arranged to inhibit the transfer of thermal energy between adjacent cell packets of battery cells of the cell stack. The thermal barrier assembly may include a first seal for sealing a first interface between a heat exchanger plate and the thermal barrier assembly. A second seal may be provided for sealing a second interface between the heat exchanger plate and a structural plate member of the cell stack. A third seal may be provided for sealing a third interface between the heat exchanger plate and cross-member assembly of the cell stack. The first, second, and third seals may cooperate to establish a seal system for sealing various gas paths across the heat exchanger plate, thereby preventing vent gases from passing from one battery cell packet to another during battery thermal events as part of a cell vent management strategy.

Abstract: A method of assembling a battery pack includes, outside of a battery pack enclosure, securing at least one first battery cell to a first side of a thermal barrier, and securing at least one second battery cell to an opposite, second side of the thermal barrier. The method provides a battery cell subassembly with the thermal barrier sandwiched between the at least one first battery cell and the at least one second battery cell.

Abstract: Cell stack end caps are provided for use within traction battery packs. An end cap may be positioned to at least partially fill a volume of space between a cell stack and an enclosure structure (e.g., an enclosure tray) inside the traction battery pack. The end cap may be configured to square a draft angle of a side wall of the enclosure structure in order to impart a compressive load to the cell stack and/or the enclosure structure. A foam structure may be positioned between the end cap and the enclosure structure or within a hollow passageway of the end cap for increasing the structural integrity of the traction battery pack.

Abstract: A battery pack venting assembly includes a first beam establishing a first side of a passageway and a second beam establishing an opposite, second side of the passageway. The passageway is configured to communicate battery cell vent byproducts. A method of establishing a vent path within a traction battery pack includes, within an enclosure assembly of a battery pack, providing a cross-member assembly having a first beam and a second beam; and communicating battery cell vent byproducts through at least one opening in the first beam into a passageway having a perimeter that is at least partially provided by the first beam and the second beam.

Abstract: A battery pack terminal retention system includes a clasp configured to hold tab terminals as the tab terminals are electrically connected together. A battery pack terminal retention method includes holding terminals together using a clasp; and electrically connecting together the plurality of terminals during the holding. The terminals can be tab terminals that are electrically connected together using welds.

Abstract: A method includes electrically connecting a first battery cell to a second battery cell by joining a first tab terminal of the first battery cell to a second tab terminal of the second battery cell. The method further includes compressing the first tab terminal and the second tab terminal after the joining. A battery assembly includes a first tab terminal extending from a first housing of a first battery cell, and a second tab terminal extending from a second housing of a second battery cell. The second tab terminal is connected directly to the first tab terminal. The method further includes an insulating layer that encloses the first and second tab terminals against the first and second housings.

Abstract: Thermal barriers are provided for traction battery packs. An exemplary thermal barrier may be positioned within a venting passageway of a traction battery pack. The thermal barrier may thermally protect upper and/or lower enclosure structures and may substantially prevent thermal energy from moving from cell stack-to-cell stack during a battery thermal event.

Abstract: A traction battery pack venting assembly includes an enclosure, at least one cell stack within the enclosure, a cross-member assembly within the enclosure, and a valve assembly that opens to provide a vent path from the at least one cell stack to a passageway of the cross-member assembly. A method of establishing a vent path within a traction battery pack includes, within a battery pack enclosure, using a valve assembly to block an opening to a passageway provided by a cross-member assembly; and in response to at least one battery cell within the battery pack enclosure venting, opening the valve assembly to permit flow through the opening to the passageway.

Abstract: Multifunctional cross-member beams are provided for use within traction battery packs. An exemplary cross-member beam may include features for interfacing with and supporting various subcomponents (e.g., battery cells, cell tab terminals, bus bars, thermal barriers, etc.) of a cell stack of the traction battery pack. The cross-member beam may further incorporate features for facilitating the venting of battery cell vent byproducts during battery thermal events.

Abstract: Banding straps and associated methods may be used for assembling a cell stack of a traction battery pack. One more banding straps may be arranged about the cell stack for temporarily or permanently applying and maintaining compression across the cell stack. In an exemplary method, a banding strap may be arranged within a compression fixture before positioning a cell stack within the compression fixture and applying a compressive force across a cell stack axis of the cell stack. Free end portions of the banding strap may be connected to maintain the compressive force across the cell stack axis.

Abstract: Divider fins are disclosed for traction battery packs. An exemplary divider fin may be arranged between adjacent battery cells of a battery cell stack. The divider fin may include an upper fin portion configured to interface with an enclosure cover, and a lower fin portion configured to interface with an enclosure tray or a heat exchange plate. The divider fin may be configured to compartmentalize the cell stack, structurally join upper and lower battery structures, contain thermal energy during battery thermal events, etc.

Abstract: A traction battery pack assembly includes a battery pack enclosure that provides an interior area, and at least one cell stack that includes battery cells and at least one divider distributed along a cell stack axis. The at least one divider compartmentalizes the interior area into a plurality of compartments. Each of the compartments holds at least one of the battery cells.

Abstract: Electrical connection systems are provided for electrically connecting cell stacks of a traction battery pack. Exemplary electrical connections systems 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 the first cell stack, and the second high voltage terminal may be mounted to a second cross-member beam of the second cell stack. The 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.