All-solid-state lithium-ion batteries offer enhanced safety and energy density compared to liquid electrolyte counterparts, but face challenges like lower conductivity and insufficient electrode contact. In a recent study, scientists have discovered a stable, highly conductive lithium-ion conductor in the form of a pyrochlore-type oxyfluoride. This innovation addresses the need for non-sulfide solid electrolytes, offering higher conductivity and stability and paves the way for advanced all-solid-state lithium-ion batteries with improved performance and safety.