A review of Type V composite pressure vessels and automated fibre placement based manufacturing

Hydrogen is emerging as a promising future energy medium in a wide range of industries. For mobile applications, it is commonly stored in a gaseous state within high-pressure composite overwrapped pressure vessels (COPVs). The current state of the art pressure vessel technology, known as Type V, eliminates the internal polymer gas barrier used in Type IV vessels and instead relies on carbon fibre laminate to provide structural properties and prevent gas leakage. Achieving this functionality at high pressure poses several engineering challenges that have thus far prohibited commercial application. Additionally, the traditional manufacturing process for COPVs, filament winding, has several constraints that limit the design space. Automated fibre placement (AFP), a highly flexible, robotic composites manufacturing technique, has the potential to replace filament winding for composite pressure vessel manufacturing and provide pathways for further vessel optimisation. A combination of both AFP and Type V technology could provide an avenue for a new generation of high-performance composite pressure vessels. This critical review presents key work on industry-standard Type IV vessels alongside the current state of Type V CPV technology including manufacturing developments, challenges, cost, relevance to commercial standards and future fabrication solutions using AFP. Additionally, a novel Type V CPV design concept for a two-piece AFP produced vessel is presented.