Soft XAS to investigate the redox mechanism in Mnbased disordered rocksalt materials as high-energy cathodes

Mn-based disordered rocksalts (DRX) with high initial capacity, cost-effectiveness and earth-abundance, are promising cathodes for high-energy Li-ion batteries.
Their advancement is limited by the fast capacity degradation and stability issues related to oxygen redox. This work mainly focuses on the novel Li lithium
oxyflurite DRX with Ti substitution, and Li-excess DRX, to gain a thorough understanding of the redox mechanism and its evolution upon cycling. Because soft
XAS allows probing directly the valence states of 3d transition metals and O/F anions, we expect this technique to help determine the redox-active species (Mn,
Ti and O) and monitor their electronic structure changes at different potentials and cycle numbers. This deep understanding of redox behavior in DRX cathodes
would promote their future development.