Benefits and Limitations of 226 Substitutions into Li-La-Ti-O Perovskites

• DOI: 10.1021/acs.chemmater.3c00505
• Publication Date: 2023-08-01T16:06:47Z
• Authors: Antranik Jonderian; Rui Peng; Danielle Davies; Eric McCalla

Lithium lanthanum titanate solid electrolyte has high bulk conductivity and stability at potentials but suffers from low grain boundary instability potentials. In order to mitigate these two limitations, the effect of single partial substitutions on perovskite (Li-La-Ti-O) materials was studied. The X-ray diffraction patterns showed that numerous substituents enable pure-phase perovskite, a feat could not previously be accomplished in unsubstituted materials. Bond valence mismatch is used as simple predictor substitution site shows remarkably mismatches can tolerated by structure. best had minimal impact induced minor enhancements conductivity. Some elements, such Cr Mn, increased electronic producing good candidates for composite cathode an all-solid-state battery. electrochemical limits were also shifted either higher or lower substitutions. resulted becoming material with highly reversible redox peak near 3.43 V (vs Li/Li+). A thorough screening, therefore, yields combination (unsubstituted anode/electrolyte Cr-substituted cathode) represents strong candidate elusive epitaxial battery, ideal application this class given very conductivities. extended potential limit below 1.5 V, shift would allow use Li4Ti5O12 Nb-based anodes without buffer layer. Overall, work what extent properties LLTO perovskites tuned meet various requirements.