Battery cell, battery, electrical device, and manufacturing method and device for battery cell

A battery cell may include an electrode assembly, a housing and an end cap. The electrode assembly may have a first tab. The housing may have an opening for receiving the electrode assembly. The end cap may include a cap body and a first convex part. The end cap may be provided with a liquid injection hole, and the liquid injection hole may be located inside of the outer peripheral surface of the first convex part. The first convex part may be provided with a flow guiding channel, the flow guiding channel may communicate with the liquid injection hole and penetrate the outer peripheral surface, and the flow guiding channel may be used for allowing at least part of the electrolyte solution to flow to outside of the outer peripheral surface.