BATTERY MODULE AND BATTERY PACK INCLUDING THE SAME

A battery module includes a battery cell stack in which a plurality of battery cells are stacked; a module frame for housing the battery cell stack; and a heat sink which is formed under the bottom portion of the module frame and cools the plurality of battery cells. The heat sink includes a lower plate and a partition wall portion forming a flowing path of a refrigerant, and the partition wall portion is formed of a shape memory alloy, and the shape of the partition wall portion is deformed according to temperature, thereby changing the flow of the refrigerant.