在本研究中製備一系列具有優異導電度以PAN (polyacrylonitrile) 為主體添加α-Al2O3的複合高分子電解質。由導電度量測的結果可得知本研究所製備的複合高分子電解質在添加7.5wt.﹪α-Al2O3及F=0.6 LiClO4組成下在30℃之導電度可達5.7×10-4S/cm,此導電度在已知固態高分子電解質中為最高的值(1)。此外,利用線性掃瞄伏安法(linear sweep voltammetry,LSV)和循環伏安法(cyclic voltammetry,CV)來探討高分子電解質的電化學穩定性並利用交流阻抗分析法及掃瞄式電子顯微鏡(SEM)來觀察鋰金屬與電解質之間界面性質的變化,並探討α-Al2O3的添加對PAN高分子電解質與鋰金屬界面性質的影響。最後在以充放電測試來瞭解其充放電特性。 由以上實驗結果顯示,在本研究中所製備出的高分子電解質有著優異的電化學穩定性與高氧化破壞電壓(4.7V vs.Li/Li+),並且與鋰金屬之間有著好的相容性,與適當的電極材料搭配之下,預期將可製備成具實用價值的鋰金屬二次電池。
In this study, a series of solid-type α-Al2O3-containing polyacylonitrile (PAN) -based composite polymer electrolytes (CPE) with high mechanical strength and high conductivity at room temperature has been prepared. The best conductivity obtained at room temperature is 5.7 ×10-4 S cm-1 from the CPE with 7.5 wt.﹪α-Al2O3 and 0.6 LiClO4 per PAN repeat unit .In this work the electrochemical characteristics of the CPE are reported and discussed. A study of the electrochemical stability of the electrolytes by linear sweep voltammetry and cyclic voltammetry confirmed that the PAN/ LiClO4/α-Al2O3 polymer electrolytes prepared have high limit voltage ( 4.7V vs.Li/Li+) and good cyclability . The impedance spectra indicated that dispersingα-Al2O3 in the polymer electrolytes reduced the interfacial resistance and improved the interfacial stability efficiently.In addition , the charge- discharge measurements are investigated.