A Comparative View of Alkaline and Alkaline-Earth Element Intercalation into Perovskite-Type AxLayTiO3 (A = Li, Na, or Mg) Based on Theoretical Calculations and Experiments

Abstract

Perovskite-type titanates are candidates as a solid-state electrolyte for alkali metal-ion batteries, although their composition, synthesis temperature, microstructure, and cationic disorder influence on their ionic conductivity must be optimized. On the other hand, it is less known that perovskite-type lithium lanthanum titanate is interesting as electrode material for lithium batteries. Its reversible capacity is strongly affected by the ion distribution. Having this in mind, we have evaluated titanate perovskites AxLayTiO3, with A = Li, Na and (x + y) ≤ 1, as electrode active material for lithium, sodium, and magnesium batteries. We discuss whether the structure has available sites for further intercalation of univalent (lithium and sodium) and divalent (magnesium) cations. Using both theoretical calculations and experimental results, it is concluded and justified that AxLayTiO3 is very suitable as an electrode for lithium batteries at room temperature, but not for sodium and magnesium batteries