A battery module includes a plurality of battery cells; a module case configured to accommodate the plurality of battery cells; and heatsink provided on at least one side of the module case to cool the plurality of battery cells by means of a flow of a coolant. The heatsink may include a cooling channel having a sequential arrangement of branch locations along a direction of the flow of the coolant, defined from an inlet side to an outlet side of the heatsink, where the cooling channel diverges into a plurality of branches at each of the branch locations.