A dense La0.8Sr0.2Ga0.83Mg0.17O2.815 electrolyte in pure perovskite phase was prepared by a polyacrylic acid assisted solid state reaction method, and the effects of La source on the structure and electrochemical performance were also studied. By means of XRD and SEM, the structure of this material was characterized, and the electrochemical properties were studied through AC impedance diagram. The results show that the sample presents a single perovskite-type phase after sintering at 1 450 ℃ and the relative density is 94%. The specimen has the lower activate energy and higher electrical conductivity at 600 ℃. There are two different activation energy at the turning point of 650 ℃, which are 74.6 and 42.4 kJ·mol-1, respectively. The electrical conductivity is 0.057 S·cm-1 and 0.017 S·cm-1 at the temperature of 800 ℃ and 600 ℃, respectively.
