Performance Study of Metal Hydride Hydrogen Storage Based on Thermochemical Heat Storage

A two-dimensional axisymmetric mathematical model was developed for an adiabatic hydrogen storage reactor based on the magnesium hydride and magnesium hydroxide. A sandwich reactor was proposed and compared with conventional sleeve reactor, the effect of hydrogen pressure and Mg(OH)2 thermal conductivity on hydrogen storage and thermal storage performance of the sandwich reactor was investigated. The results show that the sandwich reactor exhibits a larger heat transfer area and lower heat transfer thermal resistance than conventional sleeve reactor, which results in faster heat transfer and hydrogen storage rates. Increasing the hydrogen pressure can enhance the heat transfer between metal hydride and thermal storage material and accelerates the hydrogen and heat storage rates. In addition, improving the thermal conductivity of Mg(OH)2 is essential to further improve the performance of the sandwich MgH2-Mg(OH)2 reactor. © 2024 Science Press. All rights reserved.