Battery module

1. A battery module comprising:

a plurality of battery cell packs, each having a substantially rectangular shape, wherein each of the battery cell packs includes end portions disposed along shorter sides thereof;

a plurality of heat dissipation plates, the battery cell packs and the heat dissipation plates being alternately stacked in a stacking direction; and

a cooler that absorbs heat radiated from the battery cell packs and absorbed by the heat dissipation plates, wherein

each of the heat dissipation plates has an interlayer plate portion that is in contact with corresponding two of the battery cell packs and side wall plate portions that extend in the stacking direction with respect to the interlayer plate portion on both end sides of the interlayer plate portion and that are in contact with the cooler at outer faces thereof, and

each of the heat dissipation plates has a low thermal resistance region between the interlayer plate portion and each side wall plate portion, the low thermal resistance region having a lower thermal resistance than the interlayer plate portion,

wherein, in a cross-sectional view that is taken along the stacking direction and that includes the cooler, the cooler is arranged along side faces of the battery module at which the end portions are disposed, and

wherein, in the cross-sectional view that is taken along the stacking direction and that includes the cooler, each of the end portions of the battery cell packs is disposed in a space defined by adjacent ones of the low thermal resistance regions,

wherein the low thermal resistance region has a shape, when viewed in cross section, in which the thickness increases to form a curved concave outer face that increases in thickness in a direction from the interlayer plate portion toward the side wall plate portion.

2. The battery module according to claim 1 , wherein, in a cross-sectional view that is taken along the stacking direction and that includes the cooler, each low thermal resistance region is provided on both sides of the corresponding interlayer plate portion in a thickness direction of the interlayer plate portion.

3. The battery module according to claim 1 , wherein, in a cross-sectional view that is taken along the stacking direction and that includes the cooler, each low thermal resistance region is provided only on one side of the corresponding interlayer plate portion in a thickness direction of the interlayer plate portion.

4. The battery module according to claim 1 , wherein, in a cross-sectional view that is taken along the stacking direction and that includes the cooler, a thickness of each low thermal resistance region is larger than a thickness of the corresponding interlayer plate portion.

5. The battery module according to claim 1 , wherein the low thermal resistance regions, the interlayer plate portion and the side wall plate portions are formed of a single-piece member.

6. The battery module according to claim 1 , wherein each low thermal resistance region has a recessed portion having a shape along end portions of a corresponding one of the battery cell packs.

7. The battery module according to claim 1 , wherein adjacent ones of the side wall plate portions contact each other in the stacking direction and each of the battery cell packs is arranged in a space between adjacent two heat dissipation plates in the stacking direction.

8. The battery module according to claim 1 , wherein a portion of the battery cell packs are in direct contact with the low thermal resistance region.

9. The battery module according to claim 1 , wherein a thickness of the end portions of each battery cell pack is smaller than a thickness of a center portion of each battery cell pack.