Improving adsorption hydrogen storage performance via triply periodic minimal surface structures with uniform and gradient porosities

To improve the performance of the adsorption-based hydrogen storage via metal hydrides (MHs), high thermal conductive triply periodic minimal surface (TPMS) structures were applied in the adsorbent bed. Results showed that employing the TPMS-based structures could lead to a lower average bed temperature, a higher hydrogenation fraction and a larger adsorption amount compared to the Fins-based structure. The average temperature of the MH bed increased with increasing TPMS porosities, meanwhile the hydrogenation fraction decreased. There existed an optimal porosity leading to the maximum value of the adsorption amount. For TPMS structures with gradient porosities, at a low average porosity, the adsorption amount in Configuration II was smaller than that in Configuration I; At a high average porosity, the adsorption amount in Configuration II was larger than that in Configuration I. In Configuration II, more adsorption time was needed at low average porosities and less time at high average porosities.