Wetting device for fuel cells with polymeric membrane.

A device (11) for humidifying reagents cell stacks polymer membrane fuel fed at least with a gaseous reactant, comprising at least a first external wall (7 '') and a second external wall (7 '') delimiting a chamber containing a reticulated material (5 '') having a porosity of at least 50% at least one inlet (13, 15) for feeding at least one gaseous reactant and water, at least one outlet (12) to download humidified reagents.