DSC and electrical conductivity studies of (Li1-xKx)(2)SO4 mixed crystals

(Li1-xKx)(2)SO4 mixed crystals were prepared by the precipitation technique where x = 0.5, 0.7, 0.9 and 0.99. The phase transformations of the mixed c rystals have been analyzed by the DSC technique. The DSC curves of (Li1-xKx )(2)SO4 mixed crystals reveal that as the potassium content increases the f irst high temperature phase of the intermediate LiKSO4 phase at T=436 degre esC disappears and a two-phase mixture of LiKSO4 and K2SO4 is found for x = 0.7 and 0.9. It is observed from the electrical conductivity measurements of (Li1-xKx)(2)SO4 mixed crystals that the electrical conductivity increase s as the K2SO4 concentration increases with average activation energy of 1. 04 eV. The enhancement in the electrical conductivity is primarily a result of the presence of two ionically conducting constituents and the formation of a diffuse space charge layer at the interface region between these two phases.