本研究第一部分以固相反應法製備固態電解質Li7La3Zr2O12，並首度成功合成出純Cubic相不同鈰(Ce)摻雜量的Li7La3Zr2O12，並藉由與鎵(Ga)摻雜和未摻雜等共五種不同Li7La3Zr2O12在晶體結構及材料特性上做比較。 本研究第二部分採用刮刀塗佈法製備非獨立式固態電解質薄膜，有效解決純固態電解質與正負兩極界面阻抗過高無法正常運作問題，並藉由調配高分子(Poly(ethylene oxide) (PEO))與鋰鹽(LiTFSI)的比例(EO/Li+)、固態電解質粉末含量、固態電解質薄膜厚度來尋找刮刀塗佈法的最佳參數，在最佳參數為EO/Li+=10、0.15g-0.25Ga-Li7La3Zr2O12、刮刀厚度1000 μm時，於65 oC下搭配磷酸鋰鐵(LiFePO4)正極，在0.1C展現出放電電容值為129.4 mAh/g，庫倫效率為95.08%，高速維持率為66.54% (1C)。 本研究第三部分沿用第二部分的最佳參數，比較五種不同Li7La3Zr2O12的電化學性能，Li7La3Zr1.9Ce0.1O12展現出最優異的電化學性質，在0.1C下放電電容值達146.5 mAh/g，庫倫效率為96.51%，高速維持率達69.28% (1C)，複合型薄膜鋰離子導離子率達1.27 x 10-4 S/cm。 ;A single-phase Li7La3Zr2O12 (LLZO) solid electrolyte was synthesized using a solid-state reaction method. The influences of doping elements (Ga, Ce) on the properties of LLZO were investigated. To our best knowledge, Ce-doped LLZO was first synthesized in our laboratory. The electrochemical performance of Ce-doped was thoroughly investigated in this thesis. We prepared the non-freestanding solid state electrolyte film by the doctor-blade method to reduce the resistance between electrolyte and electrode. The hybrid electrolyte was composed of Ga-doped LLZO (Ga-LLZO), LiTFSI, Poly(ethylene oxide) was prepared. The ratio of polymer and lithium (EO/Li+) and Ga-LLZO content and the doctor blade thickness were changed to compare their electrochemical properties. The optimized solid state electrolyte film (Ga-LLZO) was able to deliver a superior Coulombic efficiency of 95.08%, a capacity of 129.4 mAh/g (@ 0.1C), and an excellent rate capability (66.54% @ 1C). We compared different LLZO with different dopants and find out that Li7La3Zr1.9Ce0.1O12 exhibited the best electrochemical performance. The ionic conductivity of hybrid(0.1Ce-LLZO) electrolyte was 1.27 x 10-4 S/cm. The battery composed of the Ce-LLZO hybride electrolyte shows a The capacity was about 146.5 mAh/g (@0.1C), a Coulombic efficiency of 96.51%. and an excellent rate capability of 69.28% @1C.
