Methylamine Lithium Borohydride as Electrolyte for All‐Solid‐State Batteries

Abstract Fast Li‐ion conductivity at room temperature is a major challenge for utilization of all‐solid‐state Li batteries. Metal borohydrides with neutral ligands are new emerging class solid‐state ionic conductors, and here we report the discovery mono‐methylamine lithium borohydride very fast + temperature. LiBH 4 ⋅CH 3 NH 2 crystallizes in monoclinic space group P 1 / c , forming two‐dimensional unique layered structure. The layers separated by hydrophobic −CH moieties, contain large voids, allowing Li‐ionic conduction interlayers, σ (Li )=1.24×10 −3 S cm −1 electronic negligible, electrochemical stability ≈2.1 V vs Li. first battery using ligand as electrolyte, Li‐metal anode TiS cathode demonstrated.