Process for supplying a fuel cell with hydrogen, which includes the steps:—intermediate storage of (poly)silanes or (poly)silane solutions—transfer of the (poly)silanes to a reaction chamber—reaction or hydrolysis of the silanes or silane solutions in the reaction chamber with an aqueous solution to liberate H2,—removal of the solid and/or liquid reaction products from the reaction chamber,—transfer of the H2 formed to the fuel cell. The invention also relates to a hydrogen generator for fuel cells based on silanes.