A new method to produce high purity hydrogen using reactions of aluminum and sodium borohydride with aqueous alkaline solutions is described. This process mainly consumes water and aluminum (or its alloys) which are cheaper raw materials than the borohydride. As a consequence, this process could be competitive for in situ production of hydrogen. Moreover, a synergistic effect has been observed in hydrogen production rates and yields combining aluminum or aluminum alloys with sodium borohydride in aqueous solutions. Good results have been obtained for powders of Al, Al/Si and Al/Co alloys. The development of this idea could improve yields and reduce costs in power units based on fuel cells which use borohydride as raw material for hydrogen production.