Microcrack Resistant Polymers Enabling Lightweight Composite Hydrogen Storage Vessels

Abstract

Robust, lightweight, storage vessels are needed for on-board storage of hydrogen. Challenges with currently used composite overwrapped vessels include weight due to the non-load bearing liner, performance reliability resulting from separation of the liner, and costs of extra manufacturing steps to fabricate the liner. Linerless composite vessels, where the composite shell serves both as a permeation barrier and a structure, can provide for the lightest weight vessels for a given set of requirements. Preliminary designs show up to 25% weight savings allowing reduced storage system mass and more internal volume. These tanks are targeted to attain hydrogen mass storage efficiency of 15-18% as compared to 3-4% from lined vessels. Manufacturing cost, operational risks and maintenance costs can be reduced due to inherently simple construction. Engineering methods that define material performance requirements, such as polymer strain requirements in a lamina have been used to guide the development of microcrack resistant polymers. Performance of linerless composite tanks has been demonstrated and qualification is on-going. INTRODUCTIONHydrogen is an ideal energy carrier that can help increase our energy diversity and security by reducing our dependence on hydrocarbon-based fuels. Hydrogen can be produced from domestic resources that are clean, diverse, and abundant; fuel cells provide a technology to use this energy in a highly efficient way, in numerous applications, with only water and heat as byproducts. The US Department of Energy's initiative and push has already put fuel cell buses on the road, and may soon put new fuel-cell powered vehicles on the nation's rails and waterways.

A Review on Industrial Perspectives and Challenges on Material, Manufacturing, Design and Development of Compressed Hydrogen Storage Tanks for the Transportation Sector

“…Type V tanks are bound to be the ultimate step in the hydrogen tank evolution and are currently the focus of intense research [96,97]. This all-composite liner-less configuration promises the lightest solution, with a more efficient use of volume, while also reducing manufacturing costs, operational risks and maintenance costs due to its inherently simpler construction [98]. Avoiding permeation, however, constitutes a major challenge once hydrogen is a gas with very small-sized molecules, usually stored at elevated pressures.…”