PHASE-RELATIONSHIPS OF LITHIUM, MANGANESE, AND CHROMIUM(III) CHLORIDES - NEW LITHIUM ION CONDUCTING MATERIALS

The phase diagram of the quaternary system LiCl - MnCl2 - CrCl3 has be en established by high-temperature X-ray diffraction and differential scanning calorimetry (DSC). The mutual solid solubility of the ternary compounds Li2MnCl4 and the novel Li5CrCl8 is relatively small despite the closely related crystal structures. Li5CrCl8 oC28underbar undergo es a phase transition to a cubic high-temperature polymorph cF56underb ar at 750 K and it melts incongruently at 835 K. The electric conducti vity of Li5CrCl8 measured by impedance spectroscopy methods is 2 x 10( -5) OMEGA-1 cm-1 at 470 K. That of Li2MnCl4 decreases with the increas e in chromium content.