Electrical energy storage module and spacer used for the same

An electrical energy storage module comprising:

• a first electrical energy storage device and a second electrical energy storage device that are disposed along an arrangement direction;
• a spacer that is disposed between the first electrical energy storage device and the second electrical energy storage device;
• and
• a restriction mechanism that restricts the first electrical energy storage device, the second electrical energy storage device, and the spacer in the arrangement direction, wherein
• the spacer includes a base part with a flat plate shape, and a plurality of tubular protrusion parts projecting from the base part to a side of the first electrical energy storage device,
• each of the plurality of tubular protrusion parts includes a peripheral wall part extending to the side of the first electrical energy storage device, and a hollow part surrounded by the peripheral wall part,
• the peripheral wall part includes a first part with relatively large thickness and a second part with relatively small thickness,
• the hollow part is provided with deviation to one side from a center of the tubular protrusion part in a plan view, and
• when a predetermined load is applied from the arrangement direction, the first part of the peripheral wall part is compressed and deformed and the second part of the peripheral wall part is buckled.