Secondary battery module

A secondary battery module comprising:

• a plurality of batteries each including an electrode assembly and a case that accommodates the electrode assembly, the case having a prismatic shape, the plurality of batteries being arranged in a first direction;
• a temperature control member that controls a temperature of each of the plurality of batteries;
• and
• a heat transfer layer sandwiched between each of the plurality of batteries and the temperature control member in a second direction orthogonal to the first direction, wherein
• the case has
• a first surface extending in a direction orthogonal to the second direction, having at least a portion in contact with the heat transfer layer, and having a first plate thickness,
• a second surface extending in a direction orthogonal to the first surface and having a second plate thickness,
• a third surface extending parallel to the second surface and facing the second surface in the first direction,
• a first corner portion provided between the first surface and the second surface in an outer surface of the case, and
• a second corner portion provided between the first surface and the third surface in the outer surface of the case,
• in a first state of each of the plurality of batteries, the electrode assembly has a first thickness in the first direction, and in a second state of each of the plurality of batteries, the electrode assembly has a second thickness in the first direction, and the second thickness is larger than the first thickness by a thickness of 1.5% or more of a dimension of the first surface in the first direction,
• the first plate thickness of the case is larger than the second plate thickness, and
• the first corner portion of the case has a first curvature radius, the second corner portion has a second curvature radius, and each of the first curvature radius and the second curvature radius is 0.5 mm or less.