The invention relates to a material for reversible hydrogen storage comprising a complex hydride based on one or more anions selected among BH4−, MgH3−, MH4− and MH63− (M=Al, Ga, In), and one or more cations, where the material has obtained amended stability due to substitution of the complex hydride phase itself.The invention also relates to a process for preparation of the material and use thereof, and a process for reversible hydrogen storage.