Modification Strategies of High-Energy Li-Rich Mn-Based Cathodes for Li-Ion Batteries: A Review

Li-rich manganese-based oxide (LRMO) cathode materials are considered to be one of the most promising candidates for next-generation lithium-ion batteries (LIBs) because of their high specific capacity (250 mAh g^-1) and low cost. However, the inevitable irreversible structural transformation during cycling leads to large irreversible capacity loss, poor rate performance, energy decay, voltage decay, etc. Based on the recent research into LRMO for LIBs, this review highlights the research progress of LRMO in terms of crystal structure, charging/discharging mechanism investigations, and the prospects of the solution of current key problems. Meanwhile, this review summarizes the specific modification strategies and their merits and demerits, i.e., surface coating, elemental doping, micro/nano structural design, introduction of high entropy, etc. Further, the future development trend and business prospect of LRMO are presented and discussed, which may inspire researchers to create more opportunities and new ideas for the future development of LRMO for LIBs with high energy density and an extended lifespan.