A type IV conformable pressure vessel has improved mechanical coupling between an outer composite shell and a boss. The pressure vessel comprises an inner polymeric liner having a flare edge fixedly coupled to the boss. The boss has a bore in fluid communication with an interior of the pressure vessel. In addition, the boss has a shank extending between the liner and the outer composite shell. The shank includes a plurality of spikes projecting radially away from the boss. The outer composite shell of resin and fiber surrounds an outer periphery of the liner and an outer periphery of the shank. The spikes are embedded into the outer composite shell to mechanically fasten the outer composite shell to the boss.

A method produces a high-pressure gas storage container that includes a liner and a reinforcing layer. The liner houses a high-pressure gas. The reinforcing layer is formed by winding a plurality of strip-shaped reinforcing members around an outer perimeter surface of the liner. The method includes irradiating plasma on at least a portion of the reinforcing fibers, and adjusting an irradiation intensity of the plasma such that an irradiation amount of the plasma with respect to the reinforcing fibers becomes constant in accordance with changes in a transport speed of the reinforcing fibers.

A plastic tank liner for the storage of a pressurized fluid includes: two ends; two elongated cylindrical sections, the two cylindrical sections having different diameters; and one connecting section connecting the two cylindrical sections. The connecting section has a concave portion connected to the cylindrical section of smaller diameter, and a convex portion adjacent to the cylindrical section of larger diameter. The convex portion has an isotensoid shape. Two convex domes are located on both ends of the plastic tank liner so that each of the domes is connected to a different cylindrical section.

A high pressure tank includes: a container body including dome parts; a reinforcement layer provided on an outer surface of the container body and including fiber-reinforced resin; and a protective member provided on an outer surface of the reinforcement layer, wherein the protective member includes a first layer disposed at the outer surface of the reinforcement layer that covers at least a part of the dome parts, and a second layer disposed outward of the first layer. The first layer is more deformable due to the same load applied from the outside than the second layer is.

A multilayer structure for transporting, distributing and storing hydrogen including, from the inside to the outside, a sealing layer and at least one composite reinforcement layer, the sealing layer including from the inside to the outside: a layer of a composition including: a short-chain polyamide thermoplastic polymer, more than 15% and up to 50% by weight of impact modifier, or including: a semi-crystalline long-chain polyamide thermoplastic polymer, up to 50% by weight of impact modifier, up to 3% by weight of plasticizer; a hydrogen barrier layer; a layer of a composition including: a short-chain polyamide thermoplastic polymer, more than 15% and up to 50% by weight of impact modifier, or including: a semi-crystalline long-chain polyamide thermoplastic polymer, up to 50% by weight of impact modifier, up to 3% of weight of plasticizer, the innermost composite reinforcement layer being wound around the sealing layer.

A high-pressure tank includes a liner for storing a fluid, and a reinforcing layer covering an outer surface of the liner and including a fiber wound around the liner and a resin. The reinforcing layer includes a helical layer group including laminated helical layers, and a large-angle layer provided adjacent to the helical layer group and on the liner-side. The helical layer group includes an innermost layer that is closest to the liner and that is one of first and second helical layers respectively having the largest and second largest fiber winding angles, an outermost layer that is closest to an outer surface of the high-pressure tank and that is the other one of the first and second helical layers, and an intermediate layer disposed between the innermost and outermost layers and including a helical layer that is smaller in winding angle than the innermost and outermost layers.

Provided is a portable cylinder including a tank having an upper portion having a valve port, a mounting collar coupled to the upper portion of the tank, and a handle attached to the mounting collar. The mounting collar has an upwardly extending portion surrounding the valve port and a plurality of circumferentially spaced tabs extending radially outwardly from the upwardly extending portion, wherein a respective gap is formed between adjacent ones of the plurality of circumferentially spaced tabs. The handle includes a shroud portion including a plurality of circumferentially spaced ledges for abutting an underside of a respective one of the plurality of circumferentially spaced tabs, and at least one tab for engaging the mounting collar in one of the gaps, and a handle portion extending from the shroud portion and having one or more areas for grasping the handle.

Provided is a method for producing a high-pressure tank that is capable of suppressing entry of a resin in a stiffener layer into the boundary between a liner body and a mouthpiece, and also offers excellent productivity. The method for producing a high-pressure tank includes disposing a resin sheet on a liner body having a mouthpiece, the resin sheet covering a gap between an outer circumferential portion of the mouthpiece and the liner body, and heating the resin sheet and welding the resin sheet to the mouthpiece and the liner body, to make a liner; and forming a fiber layer around the outer circumference of the liner, the fiber layer being impregnated with a resin, and curing the resin, wherein the softening point of a material constituting the resin sheet is higher than the maximum temperature that is reached by the liner due to heating of the resin.

A compressed gas energy storage system may include an accumulator for containing a layer of compressed gas atop a layer of liquid. A gas conduit may have an upper end in communication with a gas compressor/expander subsystem and a lower end in communication with accumulator interior for conveying compressed gas into the compressed gas layer of the accumulator when in use. A shaft may have an interior for containing a quantity of a liquid and may be fluidly connectable to a liquid source/sink via a liquid supply conduit. A partition may cover may separate the accumulator interior from the shaft interior. An internal accumulator force may act on the inner surface of the partition and the liquid within the shaft may exert an external counter force on the outer surface of the partition, whereby a net force acting on the partition is less than the accumulator force.

A type IV pressure vessel has improved permeate gas management. The pressure vessel comprises an inner polymeric liner, a breather layer disposed on the liner, and an outer composite shell structure disposed on the breather layer. The breather layer is gas permeable, impermeable to liquids, and provides a flow passageway for gas permeating through the liner wall collected by the breather layer. The outer composite shell is formed by one or more layers of fiber of a first fiber type and resin. Gas permeating from an interior space of the liner is received by the breather layer and directed to a predetermined exit location on the pressure vessel.