Disclosed herein is a structure that comprises a tank including an outer cylindrical surface and a domed end. The structure also comprises a tank skirt positioned circumferentially around the tank. A wall of the tank and a wall of the tank skirt form two sides of a y-joint between the tank and the tank skirt. The y-joint includes a wedge structure positioned between the tank and the tank skirt. Additionally, a thickness of at least one of the wall of the tank or the wall of the tank skirt forming the y-joint tapers such that the thickness of the at least one of the wall of the tank or the wall of the tank skirt that tapers has a greater thickness at the y-joint than away from the y-joint.

A member for manufacturing a high-pressure tank liner is provided for producing a high-pressure tank liner with better welding quality between its liner halves than conventional products. The high-pressure tank liner is produced by welding together a pair of liner halves that have cylindrical bodies to be connected with each other on each joint portion having an opening at its one end. The member includes: the liner half; and a cap member that is easily attached to and removed from a communication tube of the liner half, which communication tube is formed on another end opposite to the joint portion between the liner halves and causes an inside and an outside of the high-pressure tank liner to communicate with each other.

A member for manufacturing a high-pressure tank liner is provided for producing a high-pressure tank liner with better welding quality between its liner halves than conventional products. The high-pressure tank liner is produced by welding together a pair of liner halves that have cylindrical bodies to be connected with each other on each joint portion having an opening at its one end. The member includes: the liner half; and a cap member that is easily attached to and removed from a communication tube of the liner half, which communication tube is formed on another end opposite to the joint portion between the liner halves and causes an inside and an outside of the high-pressure tank liner to communicate with each other.

A composite pressure vessel assembly includes a first vessel having a first inner layer and a second vessel having a second inner layer. An outer layer of the assembly is in contact with and substantially envelopes the first and second inner layers. A junction of the assembly has outer boundaries defined by segments of the first inner layer, the second inner layer and the outer layer. A cross-layered component of the assembly is disposed in the junction, the first and second inner layers and the outer layer for adding strength to the junction and restricting delamination.

A composite pressure vessel assembly includes a first vessel having a first inner layer and a second vessel having a second inner layer. An outer layer of the assembly is in contact with and substantially envelopes the first and second inner layers. A junction of the assembly has outer boundaries defined by segments of the first inner layer, the second inner layer and the outer layer. A cross-layered component of the assembly is disposed in the junction, the first and second inner layers and the outer layer for adding strength to the junction and restricting delamination.

A high pressure tank device includes a high pressure tank configured to supply/discharge a fluid through a supply/discharge channel, a first storage part, a leakage detection sensor provided in the first storage part for detecting leakage of the fluid, and a second storage part. The high pressure tank includes a resin liner, a reinforcement layer which covers an outer surface of the liner, and a cap having a supply/discharge hole. The first storage part can store a first fluid. The first fluid is at least one of the fluid that leaked from the supply/discharge channel and the fluid that leaked through the inside of the supply/discharge hole. The second storage part is provided independently from the first storage part, and can store a second fluid. The second fluid is the fluid that leaked from the outside of the supply/discharge hole.

A high pressure tank device includes a high pressure tank configured to supply/discharge a fluid through a supply/discharge channel, a first storage part, a leakage detection sensor provided in the first storage part for detecting leakage of the fluid, and a second storage part. The high pressure tank includes a resin liner, a reinforcement layer which covers an outer surface of the liner, and a cap having a supply/discharge hole. The first storage part can store a first fluid. The first fluid is at least one of the fluid that leaked from the supply/discharge channel and the fluid that leaked through the inside of the supply/discharge hole. The second storage part is provided independently from the first storage part, and can store a second fluid. The second fluid is the fluid that leaked from the outside of the supply/discharge hole.

A compressed gas storage system that includes a pressure vessel. The pressure vessel includes a first vessel portion and a second vessel portion in fluid communication with the first vessel portion. The pressure vessel includes a third vessel portion in fluid communication with the second vessel portion. The compressed gas storage system includes a first valve positioned between the first vessel portion and the second vessel portion and a second valve positioned between the second vessel portion and the third vessel portion. The first valve allows and impedes fluid flow between the first and the second vessel portions. The second valve allows and impedes fluid flow between the second and the third vessel portions.

A compressed gas storage system that includes a pressure vessel. The pressure vessel includes a first vessel portion and a second vessel portion in fluid communication with the first vessel portion. The pressure vessel includes a third vessel portion in fluid communication with the second vessel portion. The compressed gas storage system includes a first valve positioned between the first vessel portion and the second vessel portion and a second valve positioned between the second vessel portion and the third vessel portion. The first valve allows and impedes fluid flow between the first and the second vessel portions. The second valve allows and impedes fluid flow between the second and the third vessel portions.

Disclosed are gas cylinder assemblies for containing pressurized gas. The gas cylinder assembly has a polymeric liner and a low-permeability barrier layer. The polymeric liner a first end portion, a second end portion and a central body. The central body comprises an outer surface and an inner surface disposed between the first end and the second end. The gas cylinder assembly comprises a reinforcement structure wound over the central body. The gas cylinder assembly further comprises a metal foil interposed between the reinforcement structure and central body. The metal foil is configured to reduce permeation of contents of the polymeric liner.