Methods for assembling traction battery packs
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.
1. A method for assembling a traction battery pack, comprising:
arranging a group of battery cells in a compression fixture;
compressing the group of battery cells between a first slider plate and a second slider plate within the compression fixture to provide a first cell stack, wherein the first slider plate and the second slider plate each include a frame and a compressible material held within the frame;
positioning the first cell stack relative to an enclosure tray of the traction battery pack; and
inserting the first cell stack into a cell-compressing opening of the enclosure tray.
2. The method as recited in claim 1 , wherein the first cell stack is part of a cell-to-pack battery system of the traction battery pack.
3. The method as recited in claim 1 , comprising, after the inserting, applying a compressive force to the first cell stack via the cell-compressing opening.
4. The method as recited in claim 1 , wherein arranging the group of battery cells includes:
stacking the group of battery cells between the first slider plate and the second slider plate along a cell stack axis.
5. The method as recited in claim 4 , wherein a separator plate is disposed between each adjacent pair of battery cells of the group of battery cells.
6. The method as recited in claim 1 , wherein inserting the first cell stack into the cell-compressing opening includes:
applying a downward force to the first cell stack to move the first cell stack into the enclosure tray.
7. The method as recited in claim 1 , wherein compressing the group of battery cells includes:
applying a compression force via the compression fixture along a cell stack axis to compress the group of battery cells between the first slider plate and the second slider plate.
8. The method as recited in claim 1 , wherein positioning the first cell stack includes:
positioning the first cell stack above the enclosure tray.
9. The method as recited in claim 8 , wherein inserting the first cell stack includes:
inserting the first cell stack into the enclosure tray using a top-down approach.
10. The method as recited in claim 1 , wherein the first slider plate and the second slider plate each include a chamfered leading edge for facilitating the inserting.
11. The method as recited in claim 1 , wherein the first slider plate and the second slider plate each include a sliding surface for facilitating the inserting.
12. The method as recited in claim 1 , wherein the compressible material is configured to permit expansion of the group of battery cells within the first cell stack after the inserting.
13. The method as recited in claim 1 , comprising, prior to the compressing, attaching the first slider plate to a first battery cell of the group of battery cells with a first adhesive, and attaching the second slider plate to a second battery cell of the group of battery cells with a second adhesive.
14. The method as recited in claim 1 , comprising:
arranging a second group of battery cells in a second compression fixture;
compressing the second group of battery cells between a third slider plate and a fourth slider plate within the second compression fixture to provide a second cell stack;
positioning the second cell stack relative to the enclosure tray; and
inserting the second cell stack into the cell-compressing opening of the enclosure tray at a location adjacent to the first cell stack.
15. The method as recited in claim 1 , wherein the frame is comprised of a rigid thermoplastic or a thermoset polymer, and the compressible material is comprised of a foam.
16. The method as recited in claim 1 , comprising a first two-sided adhesive tape applied between the first slider plate and a first battery cell of the group of battery cells, and a second two-sided adhesive tape applied between the second slider plate and a second battery cell of the group of battery cells.
17. The method as recited in claim 10 , wherein the chamfered leading edge is provided by a clipped corner of the first slider plate or the second slider plate.
18. The method as recited in claim 1 , comprising a separator plate disposed between each adjacent pair of battery cells of the group of battery cells, wherein the separator plate includes a second frame and a second compressible material held within the frame.
19. The method as recited in claim 18 , wherein an entirety of the frame is separated from the second frame by a first battery cell of the group of battery cells.