The invention relates to a venting device (1) for an electrochemical battery (90). The venting device comprises at least one inlet opening (2) for receiving gases venting from the battery (90), at least one outlet opening (3) for venting the gases received from the battery (90), and at least one flame arrester element (4). The inlet opening (2) is in communication with the outlet opening (3) via the flame arrester element (4). An explosion chamber (5, 6) is located within the venting device (1) on the side of the flame arrester element (4) which is directed to the outlet opening (3). The explosion chamber (5, 6) is arranged for developing and temporarily storing an explosive mixture of the gases received from the battery (90) and oxygen from the ambient air, which explodes in case a flame occurs within the explosion chamber (5, 6), thereby blowing off the flame.