Gel-type polymer electrolytes are prepared using PVdF/PEGDA/PMMA, LiPF6/LiCF3SO3 mixed lithium salts and ceramic fillers such as Al2O3, BaTiO3 and TiO2. The electrochemical properties of these electrolytes, such as electrochemical stability, ionic conductivity and compatibility with electrodes are investigated in addition to the physical properties. The charge–discharge performances of lithium-ion polymer batteries using these get-type polymer electrolytes are investigated. The gel-type polymer electrolytes containing a mixed lithium salt of LiPF6/LiCF3SO3 (10/1, wt.%) exhibit more stable ionic conductivity and lower interfacial resistance than those containing only LiPF6. In addition, an Al2O3 filler improves interfacial stability between the electrode and the polymer electrolyte. Stacking cells (MCMB 1028/LiCoO2, 8cm×13cm×7ea) composed of gel-type polymer electrolytes based on PVdF/PEGDA/PMMA, LiPF6/LiCF3SO3 (10/1, wt.%) and Al2O3 filler maintain 95% of initial capacity after 100 cycles at a C/2 rate.