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The practical application of Li-rich Mn-based oxide cathode is predominately retarded by the capacity decline and voltage fading, associated with the structure distortion and anionic redox reactions. Here, a linkagefunctionalized modification approach to tackle these challenges via a synchronous lithium oxidation strategy is reported. The doping of Ce in the bulk phase activates the pseudo-bonding effect, effectively stabilizing the lattice oxygen evolution and suppressing the structure distortion. Interestingly, it also induces the formation of spinel phase Li 4 Mn 5 O 12 in the subsurface, which in turn constructs the phase boundaries, thereby arousing the interior self-built-in electric field to prevent the outward migration of bulk oxygen anions and boost the charge transfer. Moreover, the formed coating layer Li 2 CeO 3 with oxygen vacancies accelerates Li + diffusion and mitigates electrolyte cauterization. The corresponding cathode exhibits superior longcycle stability after 300 cycles with only a 0.013% capacity drop and 1.76 mV voltage decay per cycle. This work sheds new light on the development of Li-rich Mn-based oxide cathodes toward high energy density applications.

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The practical application of lithium-ion batteries suffers from low energy density and the struggle to satisfy the ever-growing requirements of the energy-storage Internet. Therefore, developing next-generation electrode materials with high energy density is of the utmost significance. There are high expectations with respect to the development of lattice oxygen redox (LOR)a promising strategy for developing cathode materials as it renders nearly a doubling of the specific capacity. However, challenges have been put forward toward the deep-seated origins of the LOR reaction and if its whole potential could be effectively realized in practical application. In the following Review, the intrinsic science that induces the LOR activity and crystal structure evolution are extensively discussed. Moreover, a variety of characterization techniques for investigating these behaviors are presented. Furthermore, we have highlighted the practical restrictions and outlined the probable approaches of Li-based layered oxide cathodes for improving such materials to meet the practical applications.

Spinel LiMn2O4 is a promising cathode material for lithium-ion batteries ascribed to its steady bulk structure and abundant manganese sources. Nevertheless, grievous capacity decay due to the Jahn-Teller effect and...