Composite alkaline crosslinked PVA/PAA-KOH-H2O solid polymer electrolyte membranes were prepared with a solution-casting method. Scanning electron microscope (SEM) micrographs showed that the membrane surface had a uniform amorphous structure. The ionic conductivity of the polymer electrolyte membranes at room temperature was investigated by AC impedance spectroscopy, which could reach 3.5×10－2 S•cm－1. Also the electrochemical stability window has been investigated by cyclic voltammetry (CV), showing that it was about 3.5 V. It was suggested that the composite alkaline polymer electrolyte membranes could be used for solid-state K2FeO4-Zn primary alkaline batteries. With the pretreatment of the solid polymer electrolyte membranes in KOH solution with different concentrations and under different discharge rates, the discharge performance of the solid-state K2FeO4-Zn batteries was studied. The results suggested that the best concentration of KOH in which the membranes were pretreated was 9 mol•L－1, and the best discharge rate was 0.4 C. The discharge capacity above 1.0 V was up to 222.6 mAh•g－1 with a preferable discharge voltage plateau.

Key words: potassium ferrate, solution-casting method, ionic conductivity, solid polymer electrolyte membrane