Ionic conductivity of solid lithium ion conductors with the spinel structure: Li2MCl4 (M = Mg, Mn, Fe, Cd)

The ionic conductivity of the polycrystalline samples of the lithium chloride spinel, Li2MCl4 (M = Mg, Mn, Fe, Cd) is measured by the help of ac techniques in the temperature range of 25–500°C. The highest conductivity of 0.3 Scm−1 at 400°C is obtained in Li2CdCl4. In addition, the solid solution, Li2−2δM1+δCl4, has been examined. It is found that Li1.9Cd1.05Cl4 has higher conductivity than that of Li2CdCl4. The phase transitions of these compounds are also discussed.