The　electrochemical　instability　of　traditional　ether-based　electrolytes　poses　a　challenge　for　their　use　in　high-voltage　lithium　metal　batteries.　Herein,　a　synergetic　optimization　strategy　was　proposed　by　introducing　an　additive　with　a　strong　electron-withdrawing　group　and　significant　steric　hindrance-isosorbide　dinitrate　(ISDN),　reconstructing　the　solvation　structure　and　solid　electrolyte　interphase　(SEI),　enabling　highly　stable　and　efficient　lithium　metal　batteries.　We　found　that　ISDN　can　strengthen　the　interaction　between　Li*　and　the　anions　of　lithium　salts　and　weaken　the　interaction　between　Li*　and　the　solvent　in　the　solvation　structure.　It　promotes　the　formation　of　a　LiF-rich　and　LiNxOy-rich　SEI　layer,　enhancing　the　uniformity　and　compactness　of　Li　deposition　and　inhibiting　solvent　decomposition,　which　effectively　expands　the　electrochemical　window　to　4.8　V.　The　optimized　Li||Li　cells　offer　stable　cycling　over　1000　h　with　an　overpotential　of　only　57.7　mV　at　1　mA　cm-2　.　Significantly,　Li||3.7　mA　h　LiFePO4　cells　retain　108.3%　of　initial　capacity　after　546　cycles　at　a　rate　of　3　C.　Under　high-loading　conditions　(Li||4.9　mA　h　LiNi0.8Co0.1Mn0.1O2　full　cells)　and　a　cutoff　voltage　of　4.5　V,　the　ISDN-containing　electrolyte　enables　stable　cycling　for　140　cycles.　This　study　leverages　steric　hindrance　and　electron-withdrawing　effect　to　synergistically　reconstruct　the　Li*　solvation　structure　and　promote　stable　SEI　formation,　establishing　a　novel　electrolyte　paradigm　for　high-energy　lithium　metal　batteries.　(c)　2025　Published　by　Elsevier　B.V.　and　Science　Press　on　behalf　of　Science　Press　and　Dalian　Institute　of　Chemical　Physics,　Chinese　Academy　of　Sciences.