Abstract: Cryogenic tank for storing liquefied H2 under regulated pressure, comprising an external tank (12), an internal tank (18) wherein the internal tank contains liquefied H2 and the space between tanks contains H2 in gas form, an open cell internal insulation (13) in the space between tanks and in contact with the surface of the inner tank, wherein said inner insulation layer (13) is embedded in the H2 gas atmosphere of the space between tanks, at least one outer insulation layer (14) in contact with the inside of the external tank (12) that includes closed-cell foams gasified with inert gases of low conductivity and that also includes an evaporator (16) that ensures that the passage of H2 to the space between tanks to maintain the balance of pressure is performed in gaseous state.