POWER MODULE

1 . A power module comprising:

a cell stack comprising a plurality of cells that are stacked;

a pair of end plates pressing and sandwiching the cell stack in the stacking direction; and

a binding member joining the pair of end plates,

wherein the binding member has a recess that fits with an edge of the cell stack extending in the stacking direction.

2 . The power module in accordance with claim 1 ,

wherein the cells and the end plates are substantially rectangular plates,

the binding member comprises four binding beams that join the corners of the end plates, and

each of the four binding beams has a recess that fits with an edge of the cell stack extending in the stacking direction.

3 . The power module in accordance with claim 2 , further comprising an auxiliary binding member capable of joining a pair of adjacent binding beams and clamping the cell stack in a direction perpendicular to the stacking direction.

4 . The power module in accordance with claim 2 ,

wherein each of the cells has a positive electrode terminal on one end face thereof and has a negative electrode terminal on the other end face which is opposite to said one end face, and

said one end faces and said the other end faces of the cells are alternately aligned on one plane of the cell stack, so that the positive electrode terminals and the negative electrode terminals are alternately aligned on one plane of the cell stack.

5 . The power module in accordance with claim 4 , wherein the cell stack has connecting plates for electrically connecting the positive electrode terminals and the negative electrode terminals.

6 . The power module in accordance with claim 5 , wherein each of the connecting plates is Z-shaped in a cross section that includes a direction parallel to the stacking direction of the cells and a direction perpendicular to the face of the connecting plate that is attached to the cell stack.