BATTERY UNIT, BATTERY, AND ELECTRIC APPARATUS

This application discloses a battery unit. The battery unit includes a housing, at least one cell, and a buffer. The at least one cell is accommodated in the housing, the buffer is disposed corresponding to a side wall of the cell, and the buffer is provided with an accommodating cavity. A periphery of the accommodating cavity includes at least one packaging structure, the packaging structure includes at least one level of packaging region with a predetermined length. When pressure in the accommodating cavity exceeds packaging strength of the packaging structure, the packaging region is opened to form a buffer space that communicates with the accommodating cavity, reducing influence caused by swelling of the cell.