Patent ID: 7431151

Claim:
A hydrogen storage tank comprising a container accommodating a hydrogen adsorbent therein, wherein said hydrogen adsorbent adsorbs hydrogen gas and accommodates said hydrogen gas in a space other than a space occupied by said hydrogen adsorbent in said container, wherein said hydrogen adsorbent is any one of [M 2 (4,4′-bipyridine) 3 (NO 3) 4 ] provided that M represents any one of Co, Ni, and Zn; [M 2 (1,4-benzenedicarboxylate anion) 2 ] provided that M represents any one of Cu and Zn; and [Fe 2 (trans-4,4′-azopyridine) 4 (NCS) 4 ]; and said hydrogen adsorbent is capable of adsorbing said hydrogen gas of a volume exceeding an occupation volume of said hydrogen adsorbent and which has an amount of endothermic heat of not more than 16 kJ per mol of hydrogen molecules when said adsorbed hydrogen gas is released.