A battery module comprising: a plurality of battery cells being stacked along a first direction, at least one barrier (150, 250, 350, 450) adjoining at least one battery cell among the plurality of battery cells; the at least one barrier (150, 250, 350, 450) comprising: a first side member (151, 251, 351, 451) arranged at a side surface of the at least one battery cell, a second side member (152, 252, 352, 452) arranged at an opposite side surface of the at least one battery cell, and a plurality of connection members (155, 255, 355, 455) being separated from one another, each connection member (155, 255, 355, 455) extending from the first side member (151, 251, 351, 451) to the second side member (152, 252, 352, 452), characterized in that a plurality of heat discharge channels extends between the first side member (151, 251, 351, 451) and the second side member (152, 252, 352, 452), wherein one discharge channel among the plurality of heat discharge channels comprises an even part (E1, E1') corresponding to a center part of the battery cell, a first slope part (S1, S1') and a second slope part (S2, S2'), wherein both slope parts (S1, S2, S1', S2') are located in peripheral portions of the heat discharge channel, wherein at least one slope part (S1, S2, S1', S2') is arranged in a central portion of one of the side members (151, 451; 152, 252, 352, 452), and wherein a width of the even part (E1, E1') is lower than a width of the both slope parts (S1, S2, S1', S2'). a plurality of battery cells being stacked along a first direction, at least one barrier (150, 250, 350, 450) adjoining at least one battery cell among the plurality of battery cells; the at least one barrier (150, 250, 350, 450) comprising: a first side member (151, 251, 351, 451) arranged at a side surface of the at least one battery cell, a second side member (152, 252, 352, 452) arranged at an opposite side surface of the at least one battery cell, and a plurality of connection members (155, 255, 355, 455) being separated from one another, each connection member (155, 255, 355, 455) extending from the first side member (151, 251, 351, 451) to the second side member (152, 252, 352, 452), a first side member (151, 251, 351, 451) arranged at a side surface of the at least one battery cell, a second side member (152, 252, 352, 452) arranged at an opposite side surface of the at least one battery cell, and a plurality of connection members (155, 255, 355, 455) being separated from one another, each connection member (155, 255, 355, 455) extending from the first side member (151, 251, 351, 451) to the second side member (152, 252, 352, 452), characterized in that a plurality of heat discharge channels extends between the first side member (151, 251, 351, 451) and the second side member (152, 252, 352, 452), wherein one discharge channel among the plurality of heat discharge channels comprises an even part (E1, E1') corresponding to a center part of the battery cell, a first slope part (S1, S1') and a second slope part (S2, S2'), wherein both slope parts (S1, S2, S1', S2') are located in peripheral portions of the heat discharge channel, wherein at least one slope part (S1, S2, S1', S2') is arranged in a central portion of one of the side members (151, 451; 152, 252, 352, 452), and wherein a width of the even part (E1, E1') is lower than a width of the both slope parts (S1, S2, S1', S2').