Abstract: Multi-piece enclosure covers are disclosed for use on traction battery packs that include cell-to-pack battery systems. An exemplary multi-piece enclosure cover may include a plurality of individually removable cover panels. The cover panels may be positioned in a shingled or overlapping fashion relative to one another for covering the cell-to-pack battery system. Each cover panel may be individually removed relative to the remaining cover panels of the enclosure cover for servicing one or more battery internal components of the traction battery pack. The unremoved cover panels may support a portion of the tensile loads acting upon an enclosure tray of the traction battery pack while another cover panel is removed.

Abstract: Traction battery packs are disclosed that include battery systems. A cell stack/cell matrix of the battery system may be positioned within an enclosure tray of the traction battery pack. A wedge insert may be positioned at an interface between the cell stack/cell matrix and a side wall of the enclosure tray. The side wall may include a draft angle. The wedge insert may be configured to translate the draft angle in order to apply a compressive load in a direction that is substantially normal to the cell stack/cell matrix.

Abstract: Battery cell grouping solutions are disclosed for assembling traction battery packs that include cell-to-pack battery systems. A cell grouping assembly may be utilized to establish a common datum reference plane relative to multiple groupings of battery cells. An exemplary assembly method may include positioning the groupings of battery cells relative to the cell grouping assembly, and then applying a compressive force to the groupings of battery cells to provide cell stacks of the cell-to-pack battery system. The grouped cell stacks may then be located to an enclosure tray of the traction battery pack.

Abstract: A traction battery pack assembly includes, among other things, first and second pieces of an enclosure having an interior area. An attachment rim is disposed at a periphery of the first piece. The attachment rim has a stand-off that includes a platform portion and turned flange. The platform portion extends outward from the interior area in a first direction. The platform portion provides an aperture. The turned flange extends away from the platform portion in a second direction and terminates at an end face. The second direction is transverse to the first direction. The aperture is configured to receive a fastener that clamps the end face against the second piece.

Abstract: Manufacturing processes are disclosed for assembling traction battery packs that include battery systems, such as cell-to-pack battery systems. An exemplary assembly method includes inserting one or more cell stacks of the cell-to-pack battery system into a cell-compressing opening of an enclosure tray. The method may involve the use of slider plates that provide sliding surfaces that facilitate the insertion of the cell stacks into the cell compressing opening.

Abstract: A traction battery pack assembly includes battery cells, an enclosure tray, an enclosure cover that is secured to enclosure tray to provide an interior area that houses the plurality of battery cells, and an electronics support plate supported by the enclosure cover. A traction battery electronics support method includes positioning battery cells of a traction battery pack within an enclosure tray of the traction battery pack, connecting at least one electronics module electrically to other components of the traction battery pack. After the connecting, the method includes securing an electronics support plate to an enclosure cover of the traction battery pack. The electronics support plate supports the at least one electronics module.

Abstract: Manufacturing processes are disclosed for assembling traction battery packs that include cell-to-pack battery systems. An exemplary assembly method includes inserting a cell matrix of the cell-to-pack battery system into a cell-compressing opening of an enclosure tray using a top-down approach. The method may include compressing a plurality of cell stacks to a desired length, compressing the cell stacks together in a transverse direction to form the cell matrix, and then installing the cell matrix as a single unit into the cell-compressing opening of the enclosure tray.

Abstract: A traction battery pack includes a cell-to-pack battery system. A selectable shim system may be used to augment a compressive load applied to one or more cell stacks of the cell-to-pack battery system. A method of assembling the traction battery pack may include measuring a first dimension associated with each cell stack of the cell-to-pack battery system, measuring a second dimension associated with an enclosure tray, and selecting an appropriately sized shim of the selectable shim system for applying a desired amount of compression to the battery cells of each cell stack when the cell stack is received within the enclosure tray.

Abstract: A battery pack assembly method includes compressing a first cell stack, compressing a second cell stack, and inserting the first cell stack together with the second cell stack into a cell-receiving opening of an enclosure structure. Another traction battery pack assembly method includes simultaneously inserting a plurality of separate cell stacks into an enclosure structure when the plurality of cell stacks are each compressed by a compression fixture and, after the inserting, compressing the plurality of cell stacks using the enclosure structure.

Abstract: A battery pack assembly method includes compressing at least one cell stack, inserting the at least one cell stack into a cell-receiving opening of an enclosure structure, and pushing at least one cell of the at least one cell stack out of the enclosure structure using a pusher. Another traction battery pack assembly method includes moving a cell stack into an enclosure structure from a compression fixture that compresses the cell stack. The cell stack includes a plurality of battery cells. After the moving, the method compresses the cell stack using the enclosure structure. The method then includes establishing electrical connections between the battery cells of the cell stack, and testing the electrical connections prior to securing a busbar to the cell stack.

Abstract: Retention assemblies are disclosed for retaining a battery cell stack/matrix relative to an enclosure tray on traction battery packs that include cell-to-pack battery systems. The retention assemblies may be positioned between a cell stack/cell matrix and an interior surface of the enclosure tray. The retention assemblies may include features such as slider panels, clips, adhesive, and/or shims designed for holding the cell stacks down at the cell stack-to-enclosure tray interface.

Abstract: Traction battery packs are disclosed that include cell-to-pack battery systems. A cell stack/cell matrix of the cell-to-pack battery system may be positioned within an irregularly shaped enclosure tray of the traction battery pack. A block insert may be positioned at an interface between the cell stack/cell matrix and an irregularly shaped interior surface of the enclosure tray. The block insert may be configured to facilitate insertion of the cell stack/cell matrix into the enclosure tray, transfer compression loads from the enclosure tray walls to the cell stack/cell matrix, resist battery cell compression loads, etc.

Abstract: A traction battery pack assembling method includes compressing a first cell stack within a first compression fixture, compressing a second cell stack within a second compression fixture, positioning the first cell stack and the first compression fixture next to the second cell stack and the second compression fixture, and inserting the first and second cell stacks into a cell-receiving opening of an enclosure structure by pushing the first and second cell stacks together into the cell-receiving opening.

Abstract: Cover attachments are disclosed for securing an enclosure cover to a cell row/battery cell separator on traction battery packs that include cell-to-pack battery systems. One or more separators of a cell-to-pack battery system may be configured to separate cell stack rows or battery cells within the cell-to-pack battery system. A cover attachment (e.g., a clip, an adhesive puck, a magnet assembly, a hook and loop assembly, a ball-and-socket assembly, etc.) may connect to a portion of the separator for securing the enclosure cover directly to the cell-to-pack battery system. The combination of the cover attachments and the separators provides for enclosure cover retention at interior regions of the cell-to-pack battery system, maintains the enclosure cover at a spaced distance apart from the battery cells of the cell-to-pack battery system, and creates a desired amount of pack-level stiffness for distributing loads through the cell-to-pack battery system.

Abstract: A battery pack cell stack removal method includes compressing a cell stack with an enclosure structure when the cell stack is received within a cell-receiving opening of the enclosure structure, and pulling a cell stack removal strap to withdrawn the cell stack from the cell-receiving opening of the enclosure structure.

Abstract: A battery pack assembly method, including: positioning at least one cell stack within an enclosure structure; moving a compressing wall against the at least one cell stack to a position where the compressing wall applies a compressive force to the at least one cell stack between the enclosure structure and the compressing wall; and securing the compressing wall to hold the at least one cell stack in the position.

Abstract: A battery pack assembly method includes holding a cell stack with a compression machine. The compression machine engages a first load plate at a first end of the cell stack and a second load plate at an opposite, second end of the cell stack during the holding. The method further includes aligning the cell stack relative to an enclosure structure while the compression machine holds the cell stack, inserting the cell stack into a cell-receiving opening of an enclosure structure, and disengaging the compression machine from the first load plate and the second load plate.

Abstract: Standoff assemblies are disclosed for use within traction battery packs that include cell-to-pack battery systems. One or more standoff assemblies may be arranged between a cell-to-pack battery system and an enclosure cover of the traction battery pack. The standoff assemblies are configured to maintain a spaced relationship between the enclosure cover and certain components (e.g., battery cells, bus bars, etc.) of the cell-to-pack battery system.

Abstract: Cell row separators are disclosed for use within traction battery packs that include cell-to-pack battery systems. An exemplary cell-to-pack battery system may include a first cell stack, a second cell stack, and a cell row separator secured to both the first cell stack and the second cell stack. The separator is adapted for structurally coupling the first cell stack and the second cell stack together.

Abstract: This disclosure details exemplary battery pack designs for use in electrified vehicles. An exemplary battery pack assembly process may include supporting one or more components, such as a heat exchanger plate, of the battery pack against deflection during the assembly process. Supporting the heat exchanger plate to keep the plate relatively flat during the battery pack assembly process improves the flow distribution of a thermal interface material (TIM), thereby achieving improved TIM coverage and improved heat transfer between battery cells and the heat exchanger plate of the battery pack.