Ultra lightweight and compact accumulator

An accumulator assembly comprising:

• a fluidly sealed housing;
• at least one accumulator cylinder within said housing, said cylinder including
• a cylindrical, gas-impermeable shell;
• a cylindrical gas-impermeable sleeve disposed within and substantially concentric with the shell, an interstitial space formed between the sleeve and the shell;
• a piston slidably disposed within the sleeve, the piston separating an interior of the sleeve into a first chamber configured to contain a compressed gas, and a second chamber configured to contain a pressurized fluid;
• a pair of removable axial closures retained to said gas-impermeable sleeve at opposing ends and sealingly engaged with corresponding opposing ends of said gas-impermeable shell, wherein at least one of the axial closures includes a gas port and a fluid port formed therein;
• and
• a removable manifold housing comprising a gas manifold and a fluid manifold fluidly connecting respective fluid ports and gas ports of said axial closures of each accumulator cylinder;
• a relief valve fluidly connected to said gas manifold and said fluid manifold;
• and
• a drain relief port formed through a wall of the manifold housing configured to drain one of said fluid and gas into said housing.