The invention relates to a separator for an electrode plate (5) of a plate-shaped electrode (3) of a battery (1), particularly a lead-acid battery. The separator comprises a separator pocket (12) providing a receiving space (13) for the electrode plate (5) and including two separator sheets (14, 15) bearing on each other, which are welded to each other along their respective longitudinal sides (16, 17). Upper front sides (18), the welding seam (19) interconnecting the upper front sides (18) presenting an interruption, which forms a recess (20) for a current-collecting lug (8)disposed on the upper outer edge of the electrode plate to pass through, the above welding seam (19), for forming a degasification opening (21), being interrupted in a rim portion adjacent to a longitudinal side (16, 17), a second welding seam (22) spaced from the above welding seam being provided which is positioned directly opposite to the degasification opening (21) of the first welding seam.