NOVELTY - The cover (10) for battery, comprises a gas collector (12) for connecting with the interior of cell of a battery and extending to a side wall (18, 20) of the cover, a cavity (22) in the side wall, a plate (26) covering the cavity and provided with a vent, and a sintered pellet lodged in the cavity and arranged so that entire gas passes through the sintered pellet and the vent towards the external medium. The vent has an upper internal surface and a lower internal surface. Distance between the upper and lower internal surface is less than or equal to 1 mm.    USE - The cover is useful for a battery, which is useful in vehicles such as cars.    ADVANTAGE - The cover can effectively evacuate the gas created by the chemical activity of the battery thus enabling good protection against explosion of the battery.    DETAILED DESCRIPTION - The cover (10) for battery, comprises a gas collector (12) for connecting with the interior of cell of a battery and extending to a side wall (18, 20) of the cover, a cavity (22) in the side wall, a plate (26) covering the cavity and provided with a vent, and a sintered pellet lodged in the cavity and arranged so that entire gas passes through the sintered pellet and the vent towards the external medium. The vent has an upper internal surface and a lower internal surface. Distance between the upper and lower internal surface is less than or equal to 1 mm. Ratio between the total surface used for the vent (through which gas passes) and the distance between the upper surface and lower surface of the vent is 2.5-4. The cavity is shifted laterally with respect to gas collector. A lateral channel is fixed in the side wall connecting the gas collector at the cavity. An intermediary chamber is located in the side channel and in which the gas collector comes out. The bottom of the intermediary chamber serves as an electrolyte collector. A passage opening is arranged in a wall of the intermediary chamber for passing the gas in the lateral channel. The intermediary chamber has a rectangle parallelepiped shape. The gas collector opening in the upper part of the intermediary chamber and the passage opening are a slit horizontal located in one of walls of the chamber just below an upper edge. The walls of the intermediate chamber rise beyond the lower edge of the gas collector to facilitate the return of the electrolyte towards the interior of the battery. Two vertical partitions are provided with a horizontal slit at different heights. The vertical walls are installed in the lateral channel in downstream of the intermediate chamber. The plate has a support of sintered pellet, which penetrates within the cavity. The sintered pellet is lodged vertically in the support of the pellet. The vent is situated before the support of the sintered pellet. The lateral channel is formed by a groove in the lateral wall of the cover and covered by a plate. The bottom of the passage opening, the center of the gas collector and the center of the sintered pellet are in same horizontal plane. The gas collector is straight and connects a plug (16) installed in the cover. The gas collector extends to two opposite walls of the cover and opening in an intermediate chamber comprising the passage opening for passing the gas in the lateral channel.    DESCRIPTION OF DRAWING(S) - The figure shows a top view of a cover for a battery.    Cover (10)    Gas collector (12)    Plug (16)    Side walls (18, 20)    Cavity (22)    Plate. (26)