A battery module according to the present application includes: a
cell assembly including a plurality of battery cells; a lower case which is opened at a top thereof and has an
accommodation space for accommodating the
cell assembly; an upper case which is coupled to the lower case to cover a top of the opening of the lower case and has a connection hole which is perforated to communicate with the
accommodation space; an upper cover which is coupled to the upper case to cover a top of the upper case, is spaced apart from the upper case to form a buffer space between the upper cover and the upper case, and has a
discharge hole which is perforated to allow the buffer space to communicate with the outside; a partition member which has a horizontally elongated shape and is disposed in the buffer space to form a movement path extending from the connection hole to the
discharge hole; and a
coupling member which is disposed in the movement path, is configured to be coupled to the partition member, and has a movement space which is perforated from one side to the other side of a main body.