An energy storage module includes a plurality of battery cells, each including a vent; a plurality of insulation spacers, at least one of the insulation spacers being located between long side surfaces of each adjacent pair of the battery cells; a cover member including an internal receiving space; a top plate coupled to a top portion of the cover member and including ducts respectively corresponding to the vents of the battery cells, and opening holes respectively corresponding to the insulation spacers; a top cover coupled to a top portion of the top plate and including discharge holes respectively corresponding to the ducts; and an extinguisher sheet located between the top cover and the top plate, configured to emit a fire extinguishing agent at a temperature exceeding a certain temperature, and including opening holes positioned to correspond to the ducts.