Defect formation and migration in Nasicon Li1+xAlxTi2−x(PO4)3

NASICON-structured materials of the composition Li1+xAlxTi2-x(PO4)3 are regarded as solid electrolytes with high Li-ion conductivity applicable in all solid-state batteries. In this study we investigate the migration paths of constituting ions and monovalent charge carriers including K+, Na+, and, H+. The results proof that Li is the most mobile species in the investigated composition and that the formation of intrinsic defects is unlikely. In addition, we find surprisingly low migration energy for oxygen vacancies in the structure of the dedicated Li-ion conductor.