Lithium metal batteries (LMBs) are highly considered as promising candidates for next-generation energy storage systems.However,routine electrolytes cannot tolerate the high potential at cathodes and low potential at anodes simultaneously,leading to severe interfacial reactions.Herein,a highly concentrated electrolyte (HCE) region trapped in porous carbon coating layer is adopted to form a stable and highly conductive solid electrolyte interphase (SEI) on Li metal surface.The protected Li metal anode can poten-tially match the high-voltage cathode in ester electrolytes.Synergistically,this ingenious design promises high-voltage-resistant interfaces at cathodes and stable SEI with abundance of inorganic components at anodes simultaneously in high-voltage LMBs.The feasibility of this interface-regulation strategy is demonstrated in Li | LiFePO4 batteries,realizing a lifespan twice as long as the routine cells,with a huge capacity retention enhancement from 46.4％ to 88.7％ after 100 cycles.This contribution proof-of-concepts the emerging principles on the formation and regulation of stable electrode/electrolyte inter-faces in the cathode and anode simultaneously towards the next-generation high-energy-density batteries.