Modeling phase transformations in Mn-rich disordered rocksalt cathodes with machine-learning interatomic potentials

Mn-rich disordered rocksalt (DRX) cathodes promise high energy density, but their performance depends on a structural evolution during electrochemical cycling. Using a fine-tuned machine learning interatomic potential, the authors performed large-scale molecular dynamics simulations to reveal this transformation. The simulations map the atomic-level transition from a disordered structure to a partially disordered, spinel-like phase. This transformed phase features enhanced Li-ion transport pathways, and the analysis further clarifies the role of Mn valence states and correlates cation ordering with intercalation voltage profiles.