High Entropy Regulation of Electrostatic Repulsion and Structural Design in Layered Oxide Cathodes for Sodium‐Ion Batteries

High entropy strategies have emerged as a promising approach for tailoring the structure and electrochemical performance of layered cathodes for sodium-ion batteries (SIBs). Although previous studies have mainly attributed these improvements to entropy-driven structural stabilization, the mechanisms governing phase formation and evolution remain poorly understood. Herein, we propose that electrostatic regulation, particularly the modulation of Na–Na and O–O repulsive interactions, provides an important mechanistic link between high entropy design and structural evolution. Compositional complexity reconstructs the TM–O bonding network, redistributes the charge compensation, alleviates local lattice distortion, and modulates interlayer interactions, thereby influencing the formation and evolution of P2- and O3-type structures during Na+ (de)intercalation. Based primarily on configurational entropy and elemental distribution, high entropy strategies can be divided into three operational categories: high entropy doping, entropy tuning, and high entropy structure. Their phase-dependent effects are then analyzed within P2, O3, and P2/O3 structural frameworks to clarify how entropy-related strategies address distinct electrostatic instabilities. ... mehrThe correlations among sodium content, entropy level, phase structure, and electrochemical behavior are further summarized to establish practical design principles for layered oxide cathodes.