商業電解液所引起之安全問題已經阻礙鋰離子電池的實際應用，因此迫切需要尋找電化學穩定、不易燃且非揮發性的替代性電解質。低溫熔融鹽之室溫離子液體(ILs)由於其不可燃、高熱穩定和寬電化學窗口等特性增加電解質之耐燃性及傳導度。儘管如此，此類電解質之循環充放電效率低，故本研究將具機械強度之高分子(poly(VdF-co-HFP))、具阻燃性之ILs(1E3mTFSI與1B3mTFSI)、提升循環壽命之有機碳酸酯類(EC、PC、DEC等)和鋰鹽(LiTFSI)結合溶劑鑄膜法提供更優化的電解質系統，同時利用SEM、XRD、SAXS、TGA、DSC與電化學儀器探討高分子電解質膜之樣貌、熱穩定性、電性及電池性能及阻抗變化等各方面之影響。純 poly(VdF-co-HFP)高分子於添加ILs/碳酸酯類/鋰鹽後，結晶度由18.0%下降至4.9%，同時結晶區域之層間距離增加結構鬆散化，而相分離亦影響膜之應用表現。1E3mTFSI系統較1B3mTFSI者佳，不僅本質上具有高離子傳導度10-3 S/cm且電位窗範圍約4.7V，於1C下放電電容量更高達118.2 mAh/g，循環壽命於0.2C下之圈數高達350圈，且其循環充放電曲線與交流阻抗測試結果息息相關。添加高熱穩定性之ILs及改善循環充放電之碳酸酯類後改善高分子電解質膜特性，促使此系統應用於高性能及高安全性之鋰離子傳導介質，並期望能取代商業電解液於鋰離子電池上之應用。

With the unstable nature of liquid electrolytes causing the safety concern of lithium-ion batteries (LIBs), polymer electrolytes have attracted interest due to their intrinsic low volatility and flammability. We report a type of polymer electrolytes comprising commercially available poly(VDF-co-HFP), ionic liquids (ILs), and carbonates, which exhibited stable solid electrolyte interface (SEI) layer and good cycling efficiency. The as-prepared polymer electrolytes exhibited improved ionic conductivity and enhanced performance of charge-discharge capacity at various C rates. The polymer electrolytes with optimized weight percentages of ILs and carbonates exhibited ionic conductivity of 10-3 S/cm and electrochemical stability window of 4.7V at room temperature. Most importantly, the long-term cyclic performance is significantly improved by adding the carbonates and the columbic efficiency remained higher than 98% over 350 cycles. This flame retarded polymer electrolyte can be applied in LIB and may be suitable in situations in great need of safety.

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