Accumulator and plug for an accumulator

The device has a housing with several cells for electrolyte, a lid (1) and a degassing system (2) arranged so that openings are above the cells and stoppers can be inserted in the openings to cover the openings with an upper part and extend towards the cells with a lower part with a slosh cage (13) around a hollow volume with slits (14) distributed over its periphery that pass through the cage to a free end (13a) of the cage. AN Independent claim is also included for the following: (a) a closure stopper for a battery.