The Universal Super Cation‐Conductivity in Multiple‐cation Mixed Chloride Solid‐State Electrolytes

As exciting candidates for next-generation energy storage, all-solid-state lithium batteries (ASSLBs) are highly dependent on advanced solid-state electrolytes (SSEs). Here, using cost-effective LaCl₃ and CeCl₃ lattice (UCl₃ -type structure) as the host and further combined with a multiple-cation mixed strategy, we report a series of UCl₃ -type SSEs with high room-temperature ionic conductivities over 10^-3 S cm^-1 and good compatibility with high-voltage oxide cathodes. The intrinsic large-size hexagonal one-dimensional channels and highly disordered amorphous phase induced by multi-metal cation species are believed to trigger fast multiple ionic conductions of Li⁺ , Na⁺ , K⁺ , Cu⁺ , and Ag⁺ . The UCl₃ -type SSEs enable a stable prototype ASSLB capable of over 3000 cycles and high reversibility at -30 °C. Further exploration of the brand-new multiple-cation mixed chlorides is likely to lead to the development of advanced halide SSEs suitable for ASSLBs with high energy density.