BATTERY MODULE

A battery module is disclosed. The battery module includes a plurality of sub-modules each including at least one battery cell and an internal bus bar electrically connected to an electrode tab of the at least one battery cell, and a bus bar assembly configured to connect the internal bus bars of the plurality of sub-modules. The bus bar assembly includes a bus bar frame detachably mounted on the plurality of sub-modules, and an external bus bar coupled to the bus bar frame and configured to electrically connect sub-modules adjacent to each other among the plurality of sub-modules.