MgH2-based hydrogen storage tank: Kinetics, reversibility, and MWCNTs content

Abstract

The de/rehydrogenation performance, mechanism, and reversibility of a MgH2-based hydrogen storage tank with enhanced packing volume of up to 337.40 mL have been investigated. Due to significant upscaling, the MWCNTs loading content significantly affects the thermal conductivity and hydrogen diffusion in the tank. By increasing the MWCNTs content from 5 to 10 wt%, the hydrogen sorption kinetics is significantly improved. This has led to an enhancement in the reversible hydrogen capacity from 38.9 to 52.5% of the theoretical value upon 10–15 hydrogen release and uptake cycles. In addition, the de/rehydrogenation behavior at different positions in the radial and axial directions of the tank have been studied by tracking temperature and pressure changes observed during the hydrogen exchange reaction and studying the chemical compositions of the sample after cycling.