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The Li‐rich Mn‐based cathode materials (LMRs) deliver excellent energy density and exhibit low cost, which are considered as the most promising cathode materials for the next generation lithium‐ion batteries. However, the irreversible redox reaction of the oxygen atoms directly leads to release oxygen and intensifies phase transformation. Besides, the local stress and strain will be generated due to the unit‐cell volume difference between R‐3m and C2/m phases, which continuously aggravates the collapse of secondary particles. Herein, the strong Nb4d−O2p−Li2s configurations at the Li1 sites of the TM‐layer in the C2/m phase and secondary particles with the radial arrangement of refined primary particles are designed to inhibit oxygen release and relieve lattice stress by Nb2O5 treatment. Meanwhile, the preferential growth of the active {010} planes is presented to obtain an excellent transmission rate of Li+. As a result, the designed LMR delivers remarkable electrochemical properties with high discharge capacity and initial coulomb efficiency of 276 mAh g−1 and 85 % at 0.1 C, outstanding cycling retention rate of 81 % after 300 cycles. This novel crystal structure combining oxygen coordination regulation and micro‐nano scale design provides inspiration for the design of high‐performance LMRs. [ABSTRACT FROM AUTHOR]

Li-rich and Mn-based layered oxides are the most promising candidates for next-generation high energy density cathode materials. However, inherent problems including poor rate performance, continuous capacity degradation, and voltage fading hinder their commercial utilization. Herein, a lattice- and interfacial-modified Li 1.2 Mn 0.54 Co 0.13 Ni 0.13 O 2 with a pristine-layered bulk structure, Na- and S-doped transition phase, and epitaxially grown Na 2 Mn (SO 4 ) 2 ( C 2/ c symmetry) layer were constructed by Na 2 S treatment. The monoclinic Na 2 Mn(SO 4 ) 2 not only acts as an interface protective layer, alleviating the harmful electrode-electrolyte reactions, but also promotes formation of oxygen vacancy in the layered structure, enhancing reversibility of oxygen redox. The Na and S surface lattice doping leads to enhanced Li + diffusion and alleviates the chance of oxygen release. With the positive effects provided by the stable interfacial layer and lattice modification, the modified cathodes with moderate Na 2 S treatment shows alleviated capacity and voltage decay and enhanced electrochemical kinetics. Especially, the washed cathode with 3 wt % Na 2 S treatment delivers a discharge specific capacity of 305 at 0.1 C and 219 mA h g -1 at 1 C, as well as 93.15% capacity retention and 88.20% voltage retention after 200 cycles at 1 C.