Supercritical cryo-compressed hydrogen storage for fuel cell electric buses

Liquid hydrogen (LH2) truck delivery and storage at dispensing sites is likely to play an important role in an emerging H2 infrastructure. We analyzed the performance of single phase, supercritical, on-board cryo-compressed hydrogen storage (CcH2) with commercially-available LH2 pump enabled single-flow refueling for application to fuel cell electric buses (FCEB). We conducted finite-element stress analyses of Type 3 CcH2 tanks using ABAQUS for carbon fiber requirement and Fe-Safe for fatigue life. The results from these analyses indicate that, from the standpoint of weight, volume and cost, 2-mm 316 stainless steel liner is preferred to aluminium 6061 alloy in meeting the required 15,000 charge-discharge cycles for 350–700 bar storage pressures. Compared to the Type 3, 350 bar, ambient-temperature H2 storage systems in current demonstration FCEBs, 500-bar CcH2 storage system is projected to achieve 91% improvement in gravimetric capacity, 175% improvement in volumetric capacity, 46% reduction in carbon fiber composite mass, and 21% lower system cost, while exceeding >7 day loss-free dormancy with initially 85%-full H2 tank.