| 초록 |
Common solvent-free solid polymer electrolytes (SPEs) are not entirely free from the drawback of lower ionic conductivity than gel polymer electrolytes. To achieve high ionic conductivity, we prepared poly(ether urethane) (PEU)-based SPEs containing a large amount of salt. In case of these SPEs, cations are conducted by ion hopping through the percolation path made of high salt concentration. Also, the polar group of soft segment and urethane group of hard segment in the PEUs can dissolve cations, and at the same time the hard segments as reinforcing fillers can greatly improve the mechanical properties of the resulting SPEs. PEU was prepared from 4,4'-methylenebis(phenyl isocyanate) (MDI), polypropylene glycol 2000 (PPG 2000), and 1,4-butanediol (1,4-BD). SPEs were made on a stainless steel electrode from a solution of PEU, N, N’-dimethyl acetamide (DMAc), and lithium trifluoromethanesulfonate (LiCF3SO3). Then we investigated the ionic conductivities by using ac impedance analyzer. |
