Polymer　electrolyte　is　one　of　the　important　components　for　developing　advanced　solid-state　lithium　batteries　(SSLBs).　However,　the　narrow　electrochemical　stability　window　restricts　the　practical　application　with　high-voltage　cathodes.　Herein,　a　series　of　composite　solid　electrolytes　(CSEs),　possessing　both　wide　electrochemical　stability　window　(up　to　5.0　V　vs.　Li+/Li)　and　high　ionic　conductivity　(over　1.35　x10(-3)　S/cm　at　25　degrees　C),　were　reported　by　integrating　SiO2　nanoparticles　into　poly(vinyl　ethylene　carbonate)　polymer　electrolyte.　The　enhanced　anti-oxidation　performances　are　mainly　caused　and　confirmed　by　the　local　intermolecular　interactions　of　hydrogen　bonds　in　CSE.　Based　on　this　CSE,　the　SSLBs　with　LiCoO2　cathode　present　good　cycle　stability　at　high　voltage,　and　the　capacity　retention　with　4.5　V　cut-off　voltage　is　about　94%　after　200　cycles.　This　work　not　only　proves　the　importance　of　intermolecular　interactions　in　CSE,　but　also　provides　an　effective　method　for　achieving　high-energy　SSLBs　with　enhanced　interface　compatibility　between　polymer　electrolyte　and　high-voltage　cathodes.