Battery assembly

1. A method for assembling a battery module, the method comprising:

providing a cell tray defining a plurality of cell holes for holding cells;

inserting cells into respective cell holes so that the cells each protrude from the cell tray at each end of the cell, wherein a first end of each cell protrudes beyond a first outermost edge of the cell tray on a first side of the cell tray and a second end of each cell protrudes beyond a second outermost edge of the cell tray on a second side of the cell tray;

attaching a first casing to the first side of the cell tray to enclose the cell ends protruding from the first side; and

attaching a second casing to the second side of the cell tray to enclose the cell ends protruding from the second side.

2. The method according to claim 1 , wherein the cells each comprise cell terminals, and the method comprises attaching electrical connections between cell terminals.

3. The method according to claim 2 , the method comprising attaching electrical connections between the cell terminals before attaching the first casing and the second casing.

4. The method according to claim 2 , wherein attaching electrical connections between cell terminals comprises attaching at least one busbar between cell terminals.

5. The method according to claim 2 , wherein the cells have a first cell terminal located on a portion of the cell protruding to the first side of the cell tray, and the method comprises attaching electrical connections between first cell terminals before attaching the first casing.

6. The method according to claim 5 , wherein the cells have a second cell terminal located on a portion of the cell protruding to the second side of the cell tray, and the method comprises attaching electrical connections between second cell terminal before attaching the second casing.

7. The method according to claim 1 , wherein the cells have a first cell terminal located on a portion of the cell protruding to the first side of the cell tray, and the method comprises attaching electrical connections between first cell terminals before attaching the first casing.

8. The method according to claim 7 , the method comprising attaching electrical connections to all of the first cell terminals before attaching the first casing.

9. The method according to claim 1 , wherein the cells have a second cell terminal located on a portion of the cell protruding to the second side of the cell tray, and the method comprises attaching electrical connections between second cell terminals before attaching the second casing.

10. The method according to claim 9 , the method comprising attaching electrical connections to all of the second cell terminals before attaching the second casing.

11. The method according to claim 1 , wherein inserting cells into respective cell holes comprises securing the cells to the cell tray.

12. The method according to claim 11 , wherein securing the cells to the cell tray comprises inserting cells into respective cell holes until an interference fit is achieved between the cell tray surrounding the cell hole and the cell inserted into the respective cell hole.

13. The method according to claim 11 , wherein securing the cells to the cell tray comprises affixing the cells to the cell tray once inserted into respective cell holes.

14. The method according to claim 1 , wherein inserting cells into respective cell holes comprises inserting cells into each of the cell holes.

15. The method according to claim 1 , wherein attaching the first casing comprises welding the first casing to the cell tray.

16. The method according to claim 1 , wherein attaching the second casing comprises welding the second casing to the cell tray.

17. The method according to claim 1 , wherein the cell holes extend through the cell tray along a first direction, the first casing is attached to the first side of the cell tray substantially in the first direction, and the second casing is attached to the second side of the cell tray substantially opposite to the first direction.

18. The method according to claim 1 , further comprising inserting cells into respective cell holes so that each cell hole holds a cell about a body portion of that cell such that a length of that cell including a further body portion and a cell terminal protrudes from either side of the cell hole.

19. A method for assembling a battery module, the method comprising:

providing a cell tray defining a plurality of cell holes for holding cells;

inserting cells into respective cell holes so that the cells each protrude from the cell tray at each end of the cell;

attaching a first casing to a first side of the cell tray to enclose the cell ends protruding from the first side cell tray, wherein the attachment between the first casing and the cell tray is impervious to fluid; and

attaching a second casing to a second side of the cell tray to enclose the cell ends protruding from the second side, wherein the attachment between the second casing and the cell tray is impervious to fluid.

20. A method for assembling a battery module, the method comprising:

providing a cell tray defining a plurality of cell holes for holding cells, each of said plurality of cell holes extending through the cell tray;

inserting cells into respective cell holes so that the cells each protrude from the cell tray at each end of the cell;

attaching a first casing to a first side of the cell tray to enclose the cell ends protruding from the first side; and

attaching a second casing to a second side of the cell tray to enclose the cell ends protruding from the second side.