隨著科技的發展，人類對於鋰電池的需求日益增大，然而使用傳統液態電解液作為電解質存在滲液及爆炸等風險，因此人們積極往膠固態電解質發展，期望能在電性與安全之間取得平衡。深共熔溶劑相較於傳統液態電解液，具有較高的熱穩定性，此外與離子液體相比具有較低的毒性與成本，在當今追求環境友善與綠色科技的潮流下極具發展潛力。
本論文將LiTSFI與N-MAc形成的共熔鹽導入高分子網絡中，利用紫外光聚合的方式將其包覆，並添加不同的無機填充物(Al2O3、TiO2和LATP)，期望能提升電解質的導離子度與電化學性質。高分子骨架以BA為主要單體，添加少量AN期望能提升電池性能表現，並加入交聯劑HDDA，形成可獨立脫模的複合高分子電解質(CPE)，最後將其應用於鋰電池，進行一系列的電化學測試與材料性質分析。
本研究發現將共熔鹽包覆於高分子電解質中能有效提升電化學穩定性與電池的可逆性。添加氧化鋁的電解質CPE-A5相較於沒有添加的GPE電解質，具有更高的導離子度(6.8 × 10-4 S cm-1)與電化學穩定窗口上限(4.6 V vs. Li/Li+)。此外其半電池0.2 C的循環壽命達400圈並仍有147 mAh g-1的電容量與95%的維持率。從對稱鋰夾測試也可看出CPE-A5對於鋰金屬具有更高的穩定性與抑制鋰枝晶生長的能力。

Deep-eutectic-solvent (DES), which are formed by mixing LiTFSI and N-methylacetamide in a molar ratio of 1:4, can be seen as a kind of promising green additive in electrolyte composition. In this study, DES is immobilized in the UV-cured poly(butyl acrylate-co-acrylonitrile) crosslinked by 1,6-hexanediol diacrylate (HDDA) to serve as a novel polymer electrolyte for lithium-metal battery (LMB). Moreover, ceramic inorganic fillers (Al2O3, TiO2, LATP) are introduced into the system to further enhance the electrical properties of the final electrolyte membranes. The results indicate that an extraordinary conductivity value of 6.8 × 10-4 S cm-1 and an improved electrochemical stability up to 4.6 V can be achieved by the sample with 5 wt% Al2O3 addition (CPE-A5) at 25 ℃, which are much better than those of the system that DES are directly infiltrated into the commercial PP separator. By virtue of above superiority, the assembled Li//CPE-A5//LFP cell can deliver a discharge capacity of 155 mAh g-1 with a 95.3% retention after 400 cycles at 0.2 C rate under 25 ℃, meaning that CPE-A5 is a potential candidate for the next-generation LMB application and the combination of the DES system and Al2O3 filler is a great strategy to upgrade the battery performance.

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