BATTERY LOWER CASING AND BATTERY SYSTEM

The disclosure relates to a battery lower casing and a battery system. The battery lower casing comprises: a support frame comprising a plurality of fixing beams that are connected end to end to form an accommodating space, wherein each of two fixing beams opposite to each other comprises a fixing portion extending toward the accommodating space, each of the fixing beams comprises fixing tabs at a side of the fixing beam away from the accommodating space, and the battery lower casing is connected to a target object through the fixing tabs; and a bottom plate connected to the fixing beams. The battery lower casing according to the disclosure carries weight of the battery module through the fixing portions of the support frame, and fixes the battery module to the vehicle through the fixing tabs. The bottom plate is only used to isolate the external environment. Therefore, the weight and manufacturing cost of the battery lower casing can be minimized.