Solid Electrolyte Ion Transport

How is ion diffusion calculated? G Ceder interprets classic Nature Materials data

Ion diffusion is a type of calculation frequently used in papers on solid-state electrolytes, positive and negative electrode materials, and interfacial transport. The ion diffusion energy barrier, as commonly discussed, essentially calculates how high an energy peak an ion needs to traverse along the lowest energy path to move from one stable position to another. The smaller this value, the easier the ion typically migrates, and the faster the diffusion.

Nat. Commun.: How do disordered structures accelerate Li⁺ transport? Deep learning potential reveals the mechanism in solid-state electrolytes

Glassy and glass-ceramic solid electrolytes exhibit high ionic conductivity, but the influence of disordered structure on Li⁺ migration remains poorly understood at the atomic scale. This paper establishes a deep learning potential function for the Li–P–S system, comparing crystalline, glassy, ​​and glass-ceramic Li₃PS₄ states. The results show that disordered glassy and interfacial phases can promote Li⁺ hopping, interphase exchange, and intracrystalline co-diffusion. Furthermore, the authors use a machine learning softness descriptor to link the degree of local structural disorder with Li⁺ migration capability, explaining why disordered structures enhance room-temperature ionic conductivity.