High Configurational Entropy Engineered Hollow Microspheres Layered Mn-Based Cathode Enabling Stress Self-Dissipation and Anionic Redox for Wide-Temperature-Workability Sodium-Ion Batteries

High-voltage (>4.3 V) P2-type Mn-based layered oxides have emerged as promising cathode materials for sodium-ion batteries (SIBs), yet its practical application is impeded by irreversible oxygen redox reaction (ORR), Jahn–Teller distortion, and microcrack formation. Herein, an innovative high configurational entropy engineered hollow microsphere of Na 0.67 Li 0.18 Co 0.08 Mn 0.71 Mg 0.13 Cu 0.08 O 2 (HEHM-NMO) as cathode material is proposed to realize stress self-dissipation and sustainable cationic/anionic redox, thereby endowing wide-temperature (−10–60 °C) workability for SIBs. It is found that the high configurational entropy enhances the electronic structure disorder (ESD) for impeding undesired oxygen escape and also optimizes the orbital hybridization (O 2p–Mn 3d) to induce reversible ORR (O 2– /O 2 n– ). By coupling high configurational entropy with hollow microspheres, spontaneous stress dissipation in HEHM-NMO is achieved during the cycling process. As a result, the HEHM-NMO cathode can provide an ultrahigh initial charge capacity of 171.7 mA h g –1 with an initial Coulombic efficiency of 92.9% at 1.5–4.5 V and still enable a retention of 85.8% after 300 cycles at 2C. Notably, it also shows a wide-temperature (−10–60 °C) workability, delivering a capacity of 152.0 mA h g –1 at −10 °C and 192.7 mA h g –1 at 60 °C (average decay: 0.12% per cycle). This work provides atomic-level insights into entropy-dominant structural and electronic regulation for activating reversible oxygen redox.