TOP COVER STRUCTURE OF BATTERY MODULE

A structure of a battery module including a battery cell laminate, a housing having an open upper end and accommodating the battery cell laminate and a top cover covering the upper end of the housing. The top cover includes: a first layer having a rigid body; a second layer having a flexible body and laminated on the first layer; a ventilation hole perforating the first layer in vertical direction; and a non-circular slit perforating the second layer in the vertical direction. The first layer and the second layer are fixed to each other along respective edges of the first layer and the second layer.