A battery module according to one embodiment of the present invention comprises: a plurality of battery cells; a module housing for accommodating a cell stack comprising the plurality of battery cells; and a sprinkler for penetrating the module housing at one side thereof in the stacking direction of the cell stack, wherein the sprinkler comprises: a coupler positioned outside the module housing and connected to a supply pipe that supplies a cooling fluid; a sprinkler head positioned inside the module housing and connected to the coupler; and an insulating cover assembly which comprises an insulating cover that covers the sprinkler head, and which comprises an impeller assembly that covers an opening part formed at one side end portion of the insulating cover in the longitudinal direction.