BATTERY CELL, BATTERY, AND ELECTRIC DEVICE

This application relates to batteries and provides a battery cell, a battery, and an electric device. The electric device includes the battery, and the battery includes one or more battery cells. Each battery cell has a casing and an electrode assembly. At least part of the casing is made of steel, and the casing includes a body and a bottom that is located at one end of the body in a first direction and may be either separate from or integrated with the body. At least part of the body is welded, and the electrode assembly is positioned in a space enclosed by the body and the bottom. This structure allows the casing wall thickness to be reduced while maintaining strength, lowering casing weight and improving the energy density of the battery cell.