BATTERY PACK

The invention provides a battery pack, which includes a plurality of batteries and a box, the plurality of batteries accommodated in the box; each battery including an explosion-proof valve; the box including a lower box for supporting the batteries and an upper box matching the lower box, wherein the upper box includes an upper plate and a lower plate, the upper plate covers the lower plate to form an accommodating space for accommodating a fire extinguishing agent; the explosion-proof valve of each battery faces the lower plate of the upper box, and the lower plate is set to be able to discharge the fire extinguishing agent from the accommodating space after being melted. When the battery occurs a thermal runaway, a generated high-temperature gas and/or flame could melt through a position of the lower plate of the upper box corresponding to the explosion-proof valve, thereby forming a melted area that is melted through on the lower plate and causing the fire extinguishing agent in the lower plate to flow rapidly from the melted area to the runaway area. On the one hand, the fire extinguishing agent cools the high-temperature gas and/or extinguishes the flame, and on the other hand, the discharged fire extinguishing agent enters the explosion-proof valve to reduce the temperature of the battery, thus inhibiting the thermal runaway of the battery.