CASE, BATTERY, AND ELECTRIC DEVICE

This application provides a case, a battery, and an electric device. The case includes a bottom plate having a composite plate and a heat exchange plate. The composite plate is made of a first material portion and a second material portion, and includes a first welding surface formed from the first material portion. The heat exchange plate has a second welding surface made of a third material, where the third material is the same as the first material. The first and second welding surfaces are welded together. By using the composite plate instead of a conventional aluminum plate, the design improves weldability between the composite plate and the heat exchange plate, thereby reducing quality issues and improving manufacturing reliability of the case.