fig8

Figure 8. (A) Alternative charge mechanisms in LRMO cathode materials. Oxidation of Mn⁴⁺ to Mn⁷⁺, followed by the spontaneous formation of peroxide or trapped oxygen molecules accompanied by the reduction of Mn^[94]. (B) TM migration in an LRMO from the octahedral TM sites via tetrahedral sites into octahedral Li sites^[95]. (C) Comparison of crystal structures. Schematic illustrations of crystal structures of O3-type (left) and O2-type (right) LRMOs with TM migration paths. Although the TM ions in the O3 structure can readily occupy Li sites that share only edges with neighboring cations, the TM ions in the O2 structure are subject to strong repulsion when they occupy Li sites that face share with neighboring cations^[98]. LRMOs: Lithium-rich manganese-based layered oxides.