US Patent 7431151 Hydrogen storage tank

A hydrogen storage tank comprises a hydrogen adsorbent accommodated in a pressure-resistant container. The hydrogen adsorbent is capable of adsorbing and retaining hydrogen gas of a volume exceeding an occupation volume occupied by the hydrogen adsorbent itself. As for the hydrogen adsorbent, the amount of endothermic heat, which is generated when the adsorbed hydrogen gas is released, is not more than 16 kJ per mol of hydrogen molecules. The hydrogen adsorbent is prevented from leaking outside of the pressure-resistant container by a filter.