Interfacial Mn Vacancy for Li-Rich Mn-Based Oxide Cathodes

Apart from the O releasing at a low rate, large polarization at a high rate is also a big challenge for Li-rich Mn-based oxide (LMO). Prussian blue (PB) with a specific redox potential is regarded as a suitable coating layer to overcome these drawbacks, while its stability is easily destroyed by the intrinsic Jahn-Teller effect after a long run. Herein, Mn vacancy (M-v) is introduced into the PB coating layer to enhance its stability. Consequently, such an electrode (M-v-PB@LMO) presents a prolonged lifespan compared to the electrode with a PB coating layer only. Furthermore, it is found that the electrode with Mn vacancy in LMO (M-v@LMO) shows superior reversibility, which displays a boosted activity of LMO. This research exhibits the advanced merits of Mn vacancy for LMO, and further work may pay more attention to strengthening of the stability of M-v@LMO.