The mechanical properties of inorganic solid electrolytes for Li batteries are typically characterised by a high Young’s modulus above 15 GPa and hardness above 1 GPa. Here, authors develop a cost-effective and mechanically compliant inorganic solid electrolyte, with reduced Young’s modulus and hardness of 1.41 and 0.22 GPa, respectively, for practical all-solid-state Li batteries.
