In the field of solid electrolytes for all-solid-state batteries (ASSBs), the comparison between β-alumina and NASICONs has been a subject of scientific exploration. However, it wasn't until 2007 that hydride materials, which have been used for hydrogen storage since 1969, were recognized for their potential as fast ion conductors . A pivotal discovery was made when it was found that Li + ions exhibited significant conduction behavior in LiBH 4 during a structural transition from orthorhombic to hexagonal at 380 K, with an approximate conductivity of 10 -3 S cm -1 . This breakthrough propelled the research focus towards hydrides and their derivatives as solid electrolytes for ASSBs, owing to their remarkable ionic conductivity, high thermal and chemical stability, lightweight nature, and favorable mechanical properties, making them an ideal interface between the electrode and electrolyte.