Li- and Mg-based borohydrides for hydrogen storage and ionic conductor

LiBH4 and Mg(BH4)2 with high theoretical hydrogen mass capacity receive significant attentions for hy-drogen storage. Also, these compounds can be potentially applied as solid-state electrolytes with their high ionic conductivity. However, their applications are hindered by the poor kinetics and reversibility for hydrogen storage and low ionic conductivity at room temperature, respectively. To address these chal-lenges, effective strategies towards engineering the hydrogen storage properties and the emerging solid-state electrolytes with improved performances have been summarized. The focuses are on the state-of-the-art developments of Li/Mg-based borohydrides with a parallel comparison of similar methods ap-plied in both hydrogen storage and solid-state electrolytes, particularly on the phase, structure, and ther-mal properties changes of Li/Mg-based borohydrides induced by milling, ion substitution, coordination, adding additives/catalysts, and hydrides. The similarities and differences between the strategies towards two kinds of applications are also discussed and prospected. The review will shed light on the future development of Li/Mg-based borohydrides for hydrogen storage and solid-state electrolytes.(c) 2023 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

The article summarizes the research progress on the use of LiBH4 and Mg(BH4)2 as hydrogen storage materials and solid-state electrolytes, and proposes effective strategies to improve their performances. It discusses the changes in the phase, structure, and thermal properties of Li/Mg-based borohydrides induced by methods such as milling, ion substitution, coordination, adding additives/catalysts, and hydrides. The similarities and differences between the strategies used for the two applications are also discussed. This review provides insights into the future development of Li/Mg-based borohydrides for hydrogen storage and solid-state electrolytes.