Experimental assessment of an industrial-scale metal hydride hydrogen storage vessel

Metal hydride (MH) storage is a promising solution for safe, high-density hydrogen storage in both mobile and stationary applications. In this work, the absorption and desorption behaviour of an industrial-scale MH vessel with a hydrogen capacity of 2.3 kg (1.8 wt% at 35 barg) is experimentally investigated under varying hydrogen mass flow, supply pressure and thermal boundary conditions. The results show that hydrogen uptake is strongly governed by heat-transfer limitations, with approximately 75 % of the total stored mass being absorbed in less than half of the filling time. During desorption, insufficient heat transfer limits discharge rates and causes a progressive decrease in delivery pressure, restricting direct coupling to hydrogen consumers such as fuel cells. Gas-quality measurements according to the ISO 14687 reveal hydrocarbon contamination in the released hydrogen. A calibrated zero-dimensional model reproduces the experimental trends within 5 % and provides a tool for system-level optimization of MH storage systems.