BATTERY PACK COMPRISING FIRE EXTINGUISHING UNIT, BATTERY RACK COMPRISING SAME, AND POWER STORAGE SYSTEM

A battery pack includes at least one battery module; a first fire extinguisher including a first fire detection sensor, a first fire extinguishing tank configured to accommodate a fire extinguishing agent therein, a first pipe configured to connect the first fire extinguishing tank and the at least one battery module so that the fire extinguishing agent is supplied from the first fire extinguishing tank to the at least one battery module, and a first valve opened to supply the fire extinguishing agent from the first fire extinguishing tank to the at least one battery module; and a second fire extinguisher including a second fire detection sensor, a second pipe having one end connected to the first pipe, a fire extinguishing agent supplier connected to the other end of the second pipe, and a second valve opened to supply the fire extinguishing agent to the first pipe through the second pipe.