Morphological properties of polymer electrolytes based on blends of polyethylene oxide and a perfluorinated polyphosphazene solvated with LiCF3SO3 with and without the addition of dispersed gamma-LiAlO2 are reported. The effect exerted on the morphology of the complex electrolytes by the addition of a plasticizer-like propylene carbonate has also been studied. Results indicate the incorporation of gamma-LiAlO2 leads to changes on the morphology of the complex electrolyte, as verified by X-ray diffraction analysis. The major effect observed by plasticizer addition was a decrease on the crystallinity of the system together with a displacement of the T-g towards lower temperatures.