Significant progress is being made in the advancement of next-generation energy storage materials by implementing Li solid-state electrolytes to produce Li all-solid-state batteries. This eliminates the use of liquid electrolytes containing highly volatile and flammable organic solvents which present significant safety issues. Li-containing materials providing fast Li ion transport pathways are fundamental in Li solid-state electrolytes and the future of all-solid-state batteries. Collaborative computationally-guided materials discovery1
has provided a workflow for identifying unexplored selection of elements containing Li ions2,3
and designing Li solid-state electrolytes.
Li ions transport is the key sought physical property and, in this contribution, we will reveal several efficient NMR methods to directly probe the Li ions dynamics in a range of recently discovered sulphide2,4–6- and oxide7–9-containing materials. We exploit a range of variable temperature multinuclear (6Li and 7Li) and multidimensional NMR approaches, such as line shape analysis, exchange phenomena and relaxometry measurements, to determine the Li ion mobility pathways, including the dimensionality of the diffusion processes, and quantify Li ions jump rates. For example, these approaches deployed on Li3AlS32 identify that Li ion diffusion is fast within the tetrahedral and tetrahedral/octahedral layers but slow between these layers limiting long range translational Li ion mobility.10 These provide a framework for the further development of more highly conductive Li solid-state electrolytes such as Li4.3AlS3.3Cl0.7.5
References: (1) Collins, C. et al. Nature 2017, 280. (2) Gamon, J. et al. Chem. Mater. 2019, 9699. (3) Vasylenko, A. et al. Nat. Commun. 2021, 5561. (4) Leube, B. T. et al. Chem. Mater. 2018, 7183. (5) Gamon, J. et al. Chem. Mater. 2021, 8733. (6) Morscher, A. et al. Chem. Mater. 2021, 2206. (7) Enciso-Maldonado, L. et al. Chem. Mater. 2015, 2074. (8) Santibáñez-Mendieta, A. B. et al. Chem. Mater. 2016, 7833. (9) Han, G. et al. J. Am. Chem. Soc. 2021, 18216. (10) Duff, B. B. et al. submitted.