PURPOSE: To raise productivity of a storage battery and the resistance to liquid leak by a method in which terminals provided in electrode groups are inserted into notched portions of the circumferential wall of a container and the notched portions are surrounded by a mold and then integrally enclosed by the same material as the cell material.

CONSTITUTION: The circumferential wall 2 of the container 1 made of a polyolefinic resin, e.g., polypropylene or polyethylene or the like, is provided with notched portions for terminals, and the terminal 4 provided in the electrode group 5 is situated in the notched portion and the mold 10 is placed so as to surround the terminal 4 and the notched portion. And, a synthetic resin melt of the same material as the cell material is extruded into the concavity 11 formed by the mold 10 to seal up the notched portion and also to form a terminal-holding part integrally with the container 1. The preferred type of the terminal 4 has the core metal 6 having a screw formed inside and the projection 7 and a notch formed outside.