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Anionic charge compensation creates conditions for realizing high capacity and energy density of Li-ion batteries cathode materials. However, the issues of voltage hysteresis, capacity attenuation, and structure transformation caused by the labile anionic redox are still difficult to solve fundamentally. The superstructure formed by a Li–Mn ordered arrangement is the intrinsic reason to trigger the anionic charge compensation. In this work, manganese-based cathode materials with series of Li–Mn ordered superstructure types have been prepared by an ion exchange method, and superstructure control of the anionic redox behavior has been synthetically investigated. With the dispersion of a LiMn6 superstructure unit, the aggregation of Li vacancies in Mn slab is gradually inhibited, which eliminates the production of O–O dimers and improves the reversibility of oxygen redox. Therefore, the voltage hysteresis and capacity fading have been significantly improved. Meanwhile, the amount of reactive oxygen species and their capacity contribution is reduced, and the sluggish electrochemical reaction kinetics of anion requires a low current density to boost the high-capacity advantage. This paper provides effective ideas for the design of various superstructures and the rational utilization of anionic redox.

Through the total cyclization of polyacrylonitrile, a bifunctional surface and abundant oxygen defects were constructed on the lithium-rich cathode, leading to an excellent electrochemical performance.

P2‐Na2/3Ni1/3Mn2/3O2 is a promising cathode material for sodium‐ion batteries (SIBs), but it faces the rapid capacity decay due to P2‐O2 phase transition. The superlattice is a stable structure, compositing it can effectively eliminate the P2‐O2 phase transition. Based on superlattice of NaLi1/3Mn2/3O2, a series of xNaLi1/3Mn2/3O2 ⋅ (1‐x)Na2/3Ni1/3Mn2/3O2 (x=0, 0.3, 0.4, 0.5) were first synthesized by compounding NaLi1/3Mn2/3O2 into Na2/3Ni1/3Mn2/3O2 in this article. The XRD and SAED show that special superlattice guarantees the structure stable of materials, resulting in a first order phase transformation to a solid solution reaction in high voltage. The composite cathode materials realize excellent cycle performance and discharge specific capacity. When x=0.4, the capacity retention rate is 82.64 % after 100 cycles, which is greatly improved compared with 30.60 % of Na2/3Ni1/3Mn2/3O2. This paper provides a new idea for using superlattice to stabilize the structure and improve the electrochemical performance for SIBs.