BATTERY PACK HAVING STRUCTURE ALLOWING INPUT OF COOLING WATER INTO BATTERY MODULE UPON OCCURRENCE OF THERMAL RUNAWAY PHENOMENON AND ESS COMPRISING SAME

A battery pack includes a pack housing; a plurality of battery modules; a water tank connected to the plurality of battery modules; a coolant tube including a main tube connected to the water tank, a plurality of supply tubes configured to connect the main tube and the battery modules to each other, and a bypass tube connected to the main tube at a point above a supply tube located at a top end among the plurality of supply tubes and at a point below a supply tube located at a bottom end; at least one sensor installed in the pack housing to detect a thermal runaway phenomenon generated in at least a part of the plurality of battery modules; and a controller configured to output a control signal for introducing a coolant into the battery module through the coolant tube when a thermal runaway phenomenon is detected by the sensor.