NOVELTY - A system for reversibly storing hydrogen comprises a storage tank having an internal volume; and a thermally conductive composite material situated in the storage tank and for reversibly storing hydrogen, where the composite material includes a three-dimensional and interconnected framework including a conductive metal extending within the internal volume of the storage tank.    USE - As system for reversibly storing hydrogen (claimed) used as fuel source for energy and as replacement for petroleum, in mobile applications such as vehicles.    ADVANTAGE - The system improves vehicle performance i.e. makes available sufficient amount of hydrogen to power fuel cell, and reduces refill times. By incorporating a three-dimensional conductive framework within a complex hydride composite, the thermal conductivity and heat management of the hydrogen storage medium is improved, and the intrinsic hydrogenation and desorption kinetics of the storage material is maintained.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following:    (1) a method (M1) of forming a material for reversible hydrogen storage within a storage tank, involving charging a mixture of a metal amide and a metal hydride to the storage tank; and chemically reacting the mixture at a reaction condition within the storage tank to form a thermally conducting composite material situated in the storage tank and for reversibly storing hydrogen, where the composite material includes a three-dimensional and interconnected framework including a conductive metal extending within the internal volume of the storage tank; and    (2) a method (M2) for reversibly storing hydrogen involving: providing a storage tank for reversibly storing hydrogen; absorbing hydrogen into a composite material situated within the storage tank, where the composite material includes a metal hydride and unreactive conductive metal framework; and desorbing hydrogen from the composite material.    DESCRIPTION OF DRAWING(S) - The figure shows schematic view of microstructure of the composite material taken in a two-dimensional system.    Nanoparticles (20)    Clusters of particles (22)    Films (24)    Conductive pathway (26)