Appropriate FeF2 enhancing interface stability of lithium battery with solid-liquid hybrid electrolyte

• The solid-liquid hybrid electrolyte S-LATP-LE05 with 0.5 wt% FeF2 achieves high ionic conductivity of 5.78×10−4 S/cm and improved interfacial stability. • FeF2 addition promotes the formation of a LiF-rich SEI layer, effectively suppressing lithium dendrite growth and enhancing cycling stability. • The Li|S-LATP-LE05|Li symmetric battery exhibits stable overpotential for over 350 hours, demonstrating excellent compatibility with lithium metal anodes. • The Li|S-LATP-LE05|LiFePO4 full battery delivers a high discharge capacity of 160 mA·h/g at 0.2C with ~99.9% coulombic efficiency, outperforming batteries without FeF2.