An assembly set for assembling a carrier framework for a stack of battery cell blocks is provided. The assembly set includes a first frame beam, a second frame beam, and a Z-shaped busbar. The Z-shaped busbar includes: a positive plate configured for connecting to positive terminals of battery cells of a first battery cell block; a negative plate configured for connecting to negative terminals of battery cells of a second battery cell block; and a connection plate connecting the positive plate and the negative plate. The Z-shaped busbar is fastened to the first frame beam and the second frame beam.