Battery cell, battery and electric device

The embodiment of the utility model provides a battery monomer, a battery and a power utilization device, the battery monomer comprises a shell, an electrode assembly, an electrode terminal and a sealing piece, the shell comprises a first wall, and a through hole is formed in the first wall; the electrode assembly is arranged in the shell, and the first wall is used for supporting the electrode assembly; the electrode terminal is arranged at the through hole and comprises a first conductive part, and the first conductive part is arranged on the side, facing the containing space, of the first wall; a seal is disposed between the electrode terminal and the first wall. When the outside of the shell is stressed, the first wall and the electrode terminal can be deformed together, and gaps are not easy to form between the sealing element between the electrode terminal and the first wall and between the sealing element and the first wall and between the sealing element and the electrode terminal, so that good sealing performance can be kept between the sealing element and the first wall and between the sealing element and the electrode terminal, the possibility of liquid leakage of the battery monomer is reduced, and the service life of the battery monomer is prolonged. Therefore, the possibility of failure of the single battery and pollution or corrosion of other mechanisms can be reduced.