Since it is generally believed that the crystalline phase of solid polymer electrolytes (SPEs) is detrimental to ion transport, a strategy using the electrospinning technique was employed to reduce the crystallinity of SPEs. In this study, poly(ethylene oxide) (PEO)-LiClO4 SPEs fabricated by this strategy were compared with SPEs fabricated by the conventional solution casting method. Scanning electron microscopy (SEM) showed the changes in the nanofibrous structure of the electrospun SPEs when lithium salts were added. Fourier transform infrared spectroscopy (FTIR) was used to ensure that the free Li+ cations of LiClO4 are coordinated with the ether oxygen groups on the PEO chains after the electrospinning process. The results of differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analyses showed that the crystalline phase is not well developed after the electrospinning process, which leads to enhanced ionic conductivities in the electrospun SPEs. Under the same chemical composition, the conductivity of the electrospun SPEs is enhanced from 1.03 × 10−7 S/cm to 3.13 × 10−5 S/cm at room temperature, compared with that of the conventional SPEs. Moreover, the ionic conductivities of the SPEs increase with temperature and obey the Arrhenius law.
關聯:
Journal of the Taiwan Institute of Chemical Engineers 116, p.279-285