A hydrogen gas storage tank includes a body including a steel bulk region and a passivating metal oxide layer adjacent to the steel bulk region, the oxide layer comprising a number of metal oxide molecules, all having a morphology, wherein at least about 51 wt. % of the number of metal oxide molecules are Fe.sub.2O.sub.3 molecules having morphologies of (012), (001), and/or (110) surface facets such that the oxide layer is configured to lower hydrogen adsorption into the steel bulk region by at least 25% compared to a steel bulk region free from the passivating metal oxide layer.

The present invention relates to a polyketone copolymer consisting of repeating units represented by general formulae (3) and (4) below, and a mixture composition thereof. The present invention has excellent has barrier properties and thus can be used for vehicle fuel tanks, vehicle hydrogen tank liners, sealed food containers, etc.

—(CH2CH2—CO)x—  (3)

—(CH2CH(CH3)—CO)y—  (4)

(wherein x and y denote the mol % of each of the general formulae (3) and (4) in a polymer).

The present invention relates to a polyketone copolymer consisting of repeating units represented by general formulae (3) and (4) below, and a mixture composition thereof. The present invention has excellent has barrier properties and thus can be used for vehicle fuel tanks, vehicle hydrogen tank liners, sealed food containers, etc.

—(CH2CH2—CO)x—  (3)

—(CH2CH(CH3)—CO)y—  (4)

(wherein x and y denote the mol % of each of the general formulae (3) and (4) in a polymer).

Disclosed are articles useful as the body of a container for containing gas under pressure, and containers which comprise the articles to which are affixed valves to control the flow of gas out of the container, wherein the articles comprise a hollow container body, having an external surface and having an opening through which gas can enter or leave the interior of the hollow container body; optionally but preferably a layer of fiber-reinforced polymer around the exterior of the container body, and an external layer of elastomer around and sealed to the external surface of the layer of fiber-reinforced polymer if present or else to the cylinder body.

Disclosed are articles useful as the body of a container for containing gas under pressure, and containers which comprise the articles to which are affixed valves to control the flow of gas out of the container, wherein the articles comprise a hollow container body, having an external surface and having an opening through which gas can enter or leave the interior of the hollow container body; optionally but preferably a layer of fiber-reinforced polymer around the exterior of the container body, and an external layer of elastomer around and sealed to the external surface of the layer of fiber-reinforced polymer if present or else to the cylinder body.

This high strength austenitic stainless steel having excellent resistance to hydrogen embrittlement includes, in terms of mass %, C: 0.2% or less, Si: 0.2% to 1.5%, Mn: 0.5% to 2.5%, P: 0.06% or less, S: 0.008% or less, Ni: 10.0% to 20.0%, Cr: 16.0% to 25.0%, Mo: 3.5% or less, Cu: 3.5% or less, N: 0.01% to 0.50%; and O: 0.015% or less, with the balance being Fe and unavoidable impurities, in which an average size of precipitates is 100 nm or less and an amount of the precipitates is 0.001% to 1.0% in terms of mass %.

This high strength austenitic stainless steel having excellent resistance to hydrogen embrittlement includes, in terms of mass %, C: 0.2% or less, Si: 0.2% to 1.5%, Mn: 0.5% to 2.5%, P: 0.06% or less, S: 0.008% or less, Ni: 10.0% to 20.0%, Cr: 16.0% to 25.0%, Mo: 3.5% or less, Cu: 3.5% or less, N: 0.01% to 0.50%; and O: 0.015% or less, with the balance being Fe and unavoidable impurities, in which an average size of precipitates is 100 nm or less and an amount of the precipitates is 0.001% to 1.0% in terms of mass %.

A gas transport vessel having a hull and a tank longitudinally received in the hull and method of constructing the tank within the hull. The vessel is designed to transport fluids, such as hydrogen or other gases and liquids. The tank has a plurality of layers that are unconnected to adjacent layers. The tank contacts the vessel at a top and bottom. The top connection, for example a connection to deck structure, supports the tank for preventing sagging. The tank may be substantially the length of the ship and located between a forward and a rearward bulkhead. Two tanks may placed adjacent one another separated by a longitudinal bulkhead. Each layer has a forward and rearward end cap constructed of multiple frusto-conical sections. A space is provided on sides of the tank to permit expansion. The tank is integral with ship structure, thereby providing additional strength to the vessel.

A gas transport vessel having a hull and a tank longitudinally received in the hull and method of constructing the tank within the hull. The vessel is designed to transport fluids, such as hydrogen or other gases and liquids. The tank has a plurality of layers that are unconnected to adjacent layers. The tank contacts the vessel at a top and bottom. The top connection, for example a connection to deck structure, supports the tank for preventing sagging. The tank may be substantially the length of the ship and located between a forward and a rearward bulkhead. Two tanks may placed adjacent one another separated by a longitudinal bulkhead. Each layer has a forward and rearward end cap constructed of multiple frusto-conical sections. A space is provided on sides of the tank to permit expansion. The tank is integral with ship structure, thereby providing additional strength to the vessel.

A hydrogen storage system includes a hydrogen storage alloy containment vessel comprising an external pressure containment vessel and a thermally conductive compartmentalization network disposed within the pressure containment vessel. The compartmentalization network creates compartments within the pressure vessel within which a hydrogen storage alloy is disposed. The compartmentalization network includes a plurality of thermally conductive elongate tubes positioned within the pressure vessel forming a coherent, tightly packed tube bundle providing a thermally conductive network between the hydrogen storage alloy and the pressure vessel. The hydrogen storage alloy is a non-pyrophoric AB.sub.2-type Laves phase hydrogen storage alloy having: an A-site to B-site elemental ratio of not more than 0.5; and an alloy composition including (in at %): Zr: 2.0-5.5, Ti: 27-31.3, V: 8.3-9.9, Cr: 20.6-30.5, Mn: 25.4-33.0, Fe: 1.0-5.9, Al: 0.1-0.4, and/or Ni: 0.0-4.0.