BATTERY MODULE ASSEMBLY

A battery module assembly includes: a frame; a plurality of battery modules accommodated in a lower portion of the frame, each of which includes a battery cell; and a protective cover extending across and protecting lower portions of the battery modules. The frame includes a plurality of support fixing portions extending in a length direction in which each of the battery modules extends and supports both sides of the battery modules. The battery modules further include fastening flanges protruding in directions from end portions adjacent to the support fixing portions and overlapping the support fixing portions in a vertical direction, and the battery modules are fixed to the lower portion of the frame by using fixing members that extend through the fastening flanges from lower sides of the fastening flanges and are accommodated in the support fixing portions.