A general molten salt method to conduct doping engineering for high-performance LiMn2O4 cathode

Abstract

The doping strategy is considered as an effective method to enhance the electrochemical performances of LiMn2O4 (LMO). There is little report on the simultaneous preparation and doping of LMO by molten salt method. Herein, a ternary molten salt of KCl@LiCl@MCl2 (M = Ni, Cu, and Co) is proposed to convert commercial MnO2 to M-doped LMO, the successful preparation is proved by various characterizations. More importantly, the doping engineering enhances the charge transfer and storage of LMO, and ex-situ XRD and XPS prove the improved structure stability of LMO in the cycling test. Therefore, Ni-doped LMO offers a high reversible capacity of 108.6 mA h g−1 at 0.05 A g−1 and a long cyclic life with 87.4 mA h g−1 after 800 cycles at 0.2 A g−1. This work offers a new idea for implementing doping strategy.