Composite conformable pressure vessel

A method for retrofitting a vehicle having a gasoline fuel tank comprising replacing said gasoline fuel tank with a pressure vessel comprising:

• at least two composite end cells, each end cell having a cross-section comprising:
• an arcuate outer wall defining a substantially constant outer wall radius;
• an arcuate upper wall having an end unitary with said outer wall at an upper-outer junction, said upper wall defining a substantially constant upper wall radius which is less than said outer wall radius;
• an arcuate lower wall having an end unitary with said outer wall at a lower-outer junction, said lower wall defining a substantially constant lower wall radius which is less than said outer wall radius;
• and
• an inner wall having an upper end unitary with said upper wall and having a lower end unitary with said lower wall;
• and
• a composite web secured about said end cells, said web comprising a substantially planar sheet which is generally tangent to said upper-outer junction of each of said end cells, and a substantially planar lower sheet which is generally tangent to said lower-outer junction of each of said end cells.

A method for retrofitting a vehicle having a gasoline fuel tank comprising replacing said gasoline fuel tank with a pressure vessel comprising:

• at least two composite end cells, each of said end cells, each of said end cells comprising a substantially semi-cylindrical portion, each of said end cells having a cross-section comprising:
• a substantially semi-circular outer wall having an outer wall radius;
• a substantially quarter-circular upper wall having an upper wall radius less than said outer wall radius, said upper wall having an end unitary with said outer wall at an upper-outer junction;
• a substantially quarter-circular lower wall having a lower wall radius substantially equal to said upper wall radius, said lower wall having an end unitary with said outer wall at a lower-outer junction;
• and
• a substantially straight inner wall having an upper end unitary with said upper wall and having a lower end unitary with said lower wall;
• and
• a composite web secured about said end cells, said web comprising a substantially planar upper sheet which is generally tangent to said upper-outer junction of each of said end cells, and a substantially planar lower sheet which is generally tangent to said lower-outer junction of each of said end cells.