Abstract: A battery module stacking device, in which a battery module including a plurality of battery cell modules arranged side by side in a first direction, includes: a holder, a stacking platform movably arranged at the holder in the first direction; and a clamping device arranged at the holder and configured to clamp the battery cell modules to be stacked and to place the battery cell modules on the stacking platform from above the stacking platform.

Abstract: A transfer device includes an automated guided vehicle, a positioning platform, and a positioning transmission mechanism. The automated guided vehicle is provided with a supporting frame; the positioning platform is arranged on the supporting frame. The positioning transmission mechanism includes a first locking assembly, a second locking assembly, and a first driving assembly connected to the first locking assembly and the second locking assembly. The first locking assembly and the second locking assembly are arranged on two opposite sides of the positioning platform at an interval in a first direction in a horizontal plane. The first driving assembly is configured to drive the first locking assembly and the second locking assembly to move toward or away from each other, such that the first locking assembly and the second locking assembly cooperate to fix a piece-to-be-transferred.