NOVELTY - The method comprises placing a flexible film bag into a chamber that is closed in a gas-tight manner and closing the chamber to be gas-tight, generating a vacuum to above or below a negative pressure in the film bag, connecting a fluid inlet on the film bag in a sealing manner to a fluid source container via a connecting line, completely filling an interior of the bag with fluid via the connecting line, hermetically closing the film bag by creating a weld seam, and cutting off the film and/or line parts located outside the seam.    USE - The method is useful for filling a battery or storage battery film bag with fluid and closing the bag (claimed), where the battery is useful for electric vehicles and the fluid includes an electrolyte.    ADVANTAGE - The method is capable of economically filling the battery or storage battery film bag with fluid any without contamination and risk of gas bubbles inside the bag.    DETAILED DESCRIPTION - The method comprises placing a flexible film bag into a chamber that is closed in a gas-tight manner and closing the chamber to be gas-tight, generating a vacuum to above or below a negative pressure in the film bag, connecting a fluid inlet on the film bag in a sealing manner to a fluid source container via a connecting line, completely filling an interior of the bag with fluid via the connecting line, hermetically closing the film bag by creating a weld seam, and cutting off the film and/or line parts located outside the seam. The seam is created such that in the process, the fluid inlet connected to the connecting line is disconnected from the interior of the film bag and the connecting line is detached from the fluid inlet or the seam runs through the connecting line. The flexible film bag contains solid components of battery or storage battery. The solid components are electrically connected to contact bar guided by a sealed seam arrester of cathode and anode. The sealing seam is placed in a sealing station, which is located inside or outside the gas-tight sealable chamber. The film bag is filled, in an upright position, with the fluid. A sealable access for fluid is provided on a head side of the bag. An adapter is introduced via the sealable access. A separable line is provided with a vacuum source in contact with the vacuum in the bag. The gas-tight sealable chamber is evacuated via a conduit, which is present in contact with the vacuum source before the chamber is sealingly connected to the access of the plastic bag and evacuated through a separate vacuum line. The interior of the bag is closed when a fluid level is reached the access of the plastic bag. The method further comprises pre-forming the battery, and setting an inner seam on an upper part of the bag interior. The solid components comprise electrodes, which are arranged on a perforated conductive substrate. Each of the electrodes is prepared by depositing a pasty electrode material on the perforated conductive substrate and then drying and/or curing.    DESCRIPTION OF DRAWING(S) - The figure shows a schematic view of a chamber.    Compartment (1)    Vacuum poet adapter (12)    Stopcock (13)    Vacuum supply line (15)    Three-way cock. (16)