Accumulator with explosion-proof valve device.

An electric accumulator, in particular of the lead acid type, comprising a container for the active elements that make up the accumulator arranged in one or more cells, and a cover (10) that closes said container, said cover having plugs (8) for sealing the access to each of the cells, said accumulator being equipped with at least one explosion-proof device for controlled venting of the gasses evolved within the accumulator during its operation. Said explosion-proof device comprises: a venting duct (83) for releasing the gas that is produced by one or more cells of the accumulator, and having a venting outlet (84) at one end of it; an element for sealing (9) the venting outlet having at least one flexible portion capable of sealing the venting duct (83) until a certain pressure is reached, above which said at least one flexible portion has one or more areas forming, in conjunction with the venti