A hydrogen storage unit which uses hydrogen storage alloys to store hydrogen, and more particularly a heat transfer management/compartmentalization system for use in such system. The hydrogen storage alloy may be divided into compartments, separated by discs, further divided into sub-compartments by a flapper wheel. The discs and flapper wheel provide for optimal heat transfer throughout the system. The compartmentalization of the vessel may prevent compaction of the hydrogen storage alloys, which could lead to excessive strain on the vessel causing damage, deformation, or rupture of the vessel.