초록 |
A lithium secondary battery using solid polymer electrolyte (SPE) is an attractive energy source for the portable devices. In common SPEs, it has been known that the polymers having nonpolar groups are not suitable for polymer matrix, because only the polar group of polymer can dissolve lithium salt and coordinate cations. The cations can move between coordinating sites on one chain or between sites on neighboring chains, promoted by the segmental motion. In this work, we prepared new composite solid polymer electrolytes consisting of PS, LiCF3SO3 and different types of Al2O3. Al2O3 can dissolve lithium salt instead of polar groups in polymer matrix. Moreover, in these PS-based composite SPEs, the transport of cations is done by ion hopping through lithium percolation path made of the high content of lithium salt instead of segmental motion. By using ac impedance analyzer and FT-IR spectroscope, we investigated the effect of the surface groups of Al2O3 on the ionic conductivity. |