Using local softness to reveal oxygen participation in redox processes in cathode materials.

In this paper, the use of chemical local softness s(r) is proposed as an alternative way of analyzing the initial redox processes that occur in cathode materials used for lithium-ion batteries. It is shown that the chemical local softness is a quantity able to capture the same effects as the standard analysis based on the projected density of states. Because of its own nature, the local softness reveals the atomic sites involved in charge-transfer events and allows a quantitative comparative analysis between different materials. As pointed out by Johannes et al. (Solid State Ion 286:83-89, 2016), this analysis can be used as an indicator of stability of cathode materials for Li-ion batteries.