Middle or large-sized battery pack of novel air cooling structure

PURPOSE: A middle or large-sized battery pack is provided to maximize space efficiency of the inside of a car and to remove the heat accumulated between unit cells while minimizing the temperature deviation of unit cells by an air cooling method. CONSTITUTION: A middle or large-sized battery pack(600) allows at least two battery modules(400a) containing a plurality of rechargeable plate-like battery cell or unit module(unit cell) to be built in a pack case(602). The battery pack removes the heat generated in charging/discharging of unit cells through an air cooling method, and has battery capacity more than 5 KWh as a drive power for vehicles.