A Comparative View of Alkaline and Alkaline-Earth Element Intercalation into Perovskite-Type A_xLa_yTiO₃ (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 A x La y TiO3, 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 A x La y TiO3 is very suitable as an electrode for lithium batteries at room temperature, but not for sodium and magnesium batteries.

New insights into tunnel-type NaxMnO2−yFy with high performance and excellent cycling stability: the impact of F-doping

“…In order to shed more light on the improved electrochemistry, the diffusion coefficient of sodium ( D Na+ ) in the framework of Na x MnO 2− y F y was calculated from the relaxation curves obtained from the results of the galvanostatic intermittent titration technique (GITT) by using the following equation: 24 For Na 0.5 MnO 2 , the values are between 10 −10 and 3.7 × 10 −13 cm 2 s −1 in the first charge, depending on the cell voltage, and between 3.3 × 10 −10 and 10 −11 cm 2 s −1 during the first discharge (Fig. 11).…”

Ion Mobility in Crystalline Battery Materials

“…Exchanging the shuttle ion in LLTO from Li + to Na + and Mg 2 + was not feasible owing to the very low mobility of the respective ions in the given hosts. [131,137] Nonetheless, in the case of Na + , switching the B-site cation from Ti 4+ to Nb 5+ or Zr 4+ could drastically improve the Na + mobility exhibiting conductivity values of ≈10 −5 S cm −1 for Na 0.25 La 0.25 NbO 3 and Na 1/3 La 1/3 Sr 1/3 ZrO 3 . [138,139] Some promising ionic conductors of an entirely different perovskite-related material's class have gained strong interest during the last decade: the so-called anti-perovskites.…”

Solid‐State Electrolytes and Electrode/Electrolyte Interfaces in Rechargeable Batteries

“…As typical perovskite, Li 0.5 La 0.5 TiO 3 is suitable for reversible Li + ion intercalation, while it's difficult to intercalate a decent amount of Na + or Mg 2 + ions due to the larger size of Na + ion and larger charge of Mg 2 + ions compared to that of Li + ions. [71] In addition, the scalable development of nanostructured perovskite oxides by controllable synthesis approaches is still a challenge. An interdisciplinary approach including solid-state physics and chemistry, advanced characterization, and multiscale computational modeling is a necessary approach to the future development of perovskite electrolytes in solid-state energy storage devices.…”

“…The vacancy concentration can be increased by partial replacement of tetravalent A‐site and B‐site cations with lower‐valences, the low‐valence cations doping will also promote the charge shift of O to the octahedral center. As typical perovskite, Li 0.5 La 0.5 TiO 3 is suitable for reversible Li + ion intercalation, while it's difficult to intercalate a decent amount of Na + or Mg 2+ ions due to the larger size of Na + ion and larger charge of Mg 2+ ions compared to that of Li + ions [71] . In addition, the scalable development of nanostructured perovskite oxides by controllable synthesis approaches is still a challenge.…”