The invention claimed is:
1. A shovel comprising:
a lower traveling body;
an upper rotating body rotatably attached to the lower traveling body; and
an electricity storage module mounted on the upper rotating body,
wherein the electricity storage module includes a plurality of electricity storage cells each having at least a pair of electrodes led out from edges of a plate-like portion in a first direction,
wherein the electricity storage cells are stacked in a thickness direction of the plate-like portions, and are connected in series by bringing the electrodes of the electricity storage cells adjacent to each other in a stack direction into contact with each other,
wherein the electrodes of each of the electricity storage cells are attached to the plate-like portion at a position deviated closer to a dorsal surface, which is one surface, than the central position of the plate-like portion in the thickness direction,
wherein the electricity storage cells adjacent to each other are arranged in the stack direction of the electricity storage cells in a posture where the dorsal surfaces face each other or in a posture where ventral surfaces opposite the dorsal surfaces face each other, and
wherein the electrodes that electrically connect the two electricity storage cells of which the dorsal surfaces face each other are in contact with each other at mutually facing surfaces of the electrodes.
2. The shovel according to claim 1 ,
wherein the electrodes that electrically connect the two electricity storage cells of which ventral surfaces opposite the dorsal surfaces face each other have a bridge structure having the electrodes bent in a direction in which the electrodes approach each other and also having the outer surface of one electrode and the inner surface of the other electrode in contact with each other.
3. The shovel according to claim 1 , wherein the electrodes that electrically connect the two electricity storage cells of which the dorsal surfaces face each other have an L-shaped structure that is bent in the stack direction.
4. The shovel according to claim 1 , further comprising: a heat transfer plate arranged between the electricity storage cells.
5. The shovel according to claim 4 , wherein when viewed from a direction parallel to the stack direction, the heat transfer plate spreads farther to the outside than the edge of the electricity storage cell in a direction different from the direction in which the electrodes are led out.
6. The shovel according to claim 1 , further comprising:
a housing that pressurizes and accommodates the plurality of electricity storage cells in the stack direction.
7. The shovel according to claim 1 , further comprising:
a fixing member, into which the electrodes in contact with each other are inserted, constraining a relative positional relationship of the two inserted electrodes in a direction orthogonal to a virtual plane parallel to both the stack direction of the electricity storage cells and the lead-out direction of the electrodes.
8. The shovel according to claim 7 , wherein the fixing member is formed from an insulating material.
9. The shovel according to claim 7 , wherein the two electrodes inserted into the fixing member include tip portions bent toward the stack direction of the electricity storage cells after being led out from the edges of the plate-like portion,
wherein the tip portions of the two electrodes inserted into the fixing member overlap each other, and
wherein the fixing member has an opening into which the two electrodes are inserted, the opening exposing the outer surface of the mutually overlapping tip portions.
10. The shovel according to claim 9 , wherein a side surface of the opening is formed with a step that regulates the insertion depth of the electrodes into the opening as the bending positions of the electrodes get into touch with the step.
11. The shovel according to claim 7 , further comprising:
a cladding film that covers each of the electricity storage cells,
wherein the fixing member is formed with a groove into which the edges of the cladding film are inserted.
12. The shovel according to claim 7 , further comprising:
another fixing member into which one electrode of each of other two electricity storage cells is inserted, the other two electricity storage cells being stacked on one of the two electricity storage cells that have the electrodes inserted into the fixing member, and said another fixing member having the same geometric shape as the fixing member,
wherein the fixing member and said another fixing member have fitting portions that fit to each other, thereby constraining the relative positions of the two fixing members in the direction orthogonal to the virtual plane.