Battery pack and electric vehicle

The invention relates to a battery pack. The battery pack comprises an outer shell, an inner shell, a first sealing piece and a second sealing piece. By arranging the battery pack, under the normal condition, the second sealing piece is in a sealing state, a storage space and a second inner cavity are separated by the second sealing piece, and a fire extinguishing medium cannot enter the second inner cavity. When a battery in the second inner cavity is in thermal runaway, the second sealing piece is positioned in the second inner cavity, so that the temperature of the second sealing piece is increased, and the second sealing piece enters a damaged state until the temperature of the second sealing piece reaches a preset temperature, namely, a communication hole cannot be sealed, and the storage space communicates with the second inner cavity. The fire extinguishing medium with pressure in the storage space can be sprayed into the second inner cavity through the communication hole, so that the battery with ther