Abstract: An automatic battery filler for adding distilled water to storage batteries, comprises an airtight closed water vessel with a spout having a discharge outlet. A spring-loaded valve has a valve stem that protrudes from the end of the spout. Means are provided to adjust the distance between the end of the valve stem and the outlet of the spout, thereby to predetermine the level at which the container will be supported on the battery by the valve stem when the valve is fully open, which in turn will predetermine the level to which the battery is filled. The adjustment is preferably effected by rotating a screw-threaded connection. The socket or the spout has a graduated scale which indicates the level to which the apparatus has been adjusted.