Battery module and battery pack including the same

A battery module comprising:

• a battery cell stack comprising a plurality of battery cells;
• a housing comprising the battery cell stack;
• and
• a heat sink located below a bottom part of the housing,
• wherein the bottom part forms an upper plate of the heat sink,
• wherein the heat sink and the bottom part of the housing form a refrigerant flow passage configured to receive a refrigerant,
• wherein the bottom part of the housing comprises a convex pattern portion protruding toward the battery cell stack,
• wherein the convex pattern portion of the bottom part of the housing is located closer to the battery cell stack, and further away from the heat sink, than a portion of the bottom part not including the convex pattern portion,
• wherein the heat sink comprises a lower plate that is joined to the bottom part of the housing, and a recessed portion on a lower surface of the lower plate, and the refrigerant flow passage is between the recessed portion of the lower plate and the bottom part of the housing,
• wherein the convex pattern portion of the bottom part of the housing is positioned to correspond to the recessed portion of the lower plate when viewed from a direction perpendicular to a surface of the bottom part, and
• wherein the portion of the convex pattern portion has a shape extending along a direction perpendicular to a stacking direction of the plurality of battery cells or a direction parallel to a stacking direction of the plurality of battery cells.