Poly(vinylidene　fluoride)　(PVDF)-based　polymer　electrolytes　have　attracted　widespread　attention　due　to　their　unique　Li+　transport　mechanism.　However,　their　low　ionic　conductivity　and　porous　structure,　as　well　as　residual　solvent　limit　their　application　at　high　current　densities.　Here,　a　composite　solid　electrolyte　(CSE)　is　developed　by　integrating　poly(vinylidene-co-trifluoroethylene)　[P(VDF-TrFE)]　in　its　all-trans　conformation　with　aminofunctionalized　metal–organic　framework　(ZIF-90-NH2).　In　such　a　CSE,　all　F　atoms　located　on　one　side　of　the　polymer　chain,　providing　fast　Li+　transport　channels.　Concurrently,　the　functionalized　ZIF-90-NH2　can　effectively　anchor　the　residual　N,　N-dimethylformamide　(DMF)　in　CSEs　while　weakening　Li+-DMF　solvent　coordination,　inducing　the　rearrangement　of　Li+　solvation　structure　and　inhibiting　the　decomposition　of　DMF　at　the　interface.　Synergistically,　ZIF-90-NH2　can　immobilize　anions　in　Li　salts,　promoting　their　dissociation.　Based　on　integrating　competitive　Li+　coordination　with　immobilized　anions,　the　obtained　CSEs　exhibit　a　high　Li+　transference　number　(0.77).　The　full　cells　with　LiFePO4　cathode　can　run　stably　over　400　cycles　at　5　C,　while　the　Li　||　LiNi0.7Co0.1Mn0.2O2　full　cells　deliver　a　high　capacity　retention　(＞85%)　after　200　cycles　at　a　charge　cutoff　voltage　of　4.5 V.　This　work　opens　up　a　new　path　for　building　CSEs　with　high　interfacial　stability　and　fast　Li+　transport.　©　2025　The　Author(s).　Advanced　Science　published　by　Wiley-VCH　GmbH.