Mechano-chemical synthesis has been employed to prepare new light weight complex borohydrides. The precursor complex borohydrides such as NaBH4 and LiBH4 have been used since these materials posses high hydrogen storage capacity of 13.0 and 19.6 wt.%. This advanced materials based technology will meet the US-DOE grand challenge technical targets. The thermal calorimetric and gravimetric analysis of these complex borohydrides exhibits the hydrogen decomposition temperature (Tdec) of 100–150° C with theoretical capacity of ∼8.0-10.0 wt%. The catalysts (e.g. ZnCl2, TiFx3) doping and destabilization of the borohydride by reacting with binary hydride (MgH2) reveals the enhancement of decomposition kinetics and reversible dehydrogenation-rehydrogenation behavior.