Battery module

A battery module comprising:

• unit cells;
• and
• a housing accommodating the unit cells therein, the housing having paths for circulating a cooling medium,
• wherein the housing comprises:
• a unit cell receptor for receiving the unit cells, the unit cell receptor having side walls defining an inner space with an inner spatial section area perpendicular to a longitudinal direction of the housing;
• and
• a cooling medium circulator having a channel extending in the longitudinal direction of the housing for circulating a cooling medium, the channel being in direct communication with the unit cell receptor at an interface, wherein the unit cell receptor is configured to receive the cooling medium from the channel at the interface;
• wherein the side walls of the unit cell receptor extend from the channel at an angle in at least two directions at the interface to provide a stepped structure.