Entropy-Stabilized High-Entropy Sulfide Anodes for Fast-Charging and Long-Life Sodium-Ion Batteries

Conversion-type transition-metal sulfides are considered attractive anode candidates for high-energy-density sodium-ion batteries (SIBs), benefiting from their high theoretical capacity, multiple redox pathways, and relatively high conductivity. However, their practical implementation is significantly restricted by poor reaction reversibility and cycling stability, which result from volume expansion and structural collapse during repeated sodium insertion and extraction. In this study, rather than relying on extrinsic nanostructuring or carbon encapsulation alone, we used high-entropy design to intrinsically stabilize sulfide conversion by constructing a single-phase high-entropy sulfide (HES) anode. The multication framework homogenizes local reaction environments, alleviates stress accumulation and structural collapse, and accelerates charge transfer and Na + diffusion, thereby enabling highly reversible sodium storage. The HES anode delivers a high initial Coulombic efficiency of 94.8%, an impressive discharge capacity of 486.1 mAh g –1 at 50 A g –1, and retains a high specific capacity of 547 mAh g –1 after 2000 cycles at 5 A g –1 . These findings highlight the great promise of the HES platform designed for regulating both conversion reversibility and structural stability for achieving fast charging, high-stability anodes in next-generation SIBs.