Enabling Extreme Fast‐Charging Lithium‐Sulfur Batteries via Interfacial Electric Field Engineering on Single‐Atom‐Anchored High‐Entropy Oxides

The sluggish oxidation kinetics of Li 2 S remain a critical bottleneck for extreme fast−charging (XFC) lithium−sulfur batteries (LSBs). Herein, a high−entropy oxide (La 0.69 Sr 0.31 )(Fe 0.21 Co 0.21 Ni 0.19 Zn 0.19 Mn 0.20 )O 3−δ (PHEO) anchored with single−atom Cu (Cu−PHEO) as an unconventional electrocatalyst, which combines the various benefits of metal single atoms and HEOs in electrocatalysis and the interfacial electric field effect is reported. Combined with theoretical calculations, comprehensive X−ray absorption fine structure (XAFS) spectroscopy, and in situ experiments, extensive analyses indicate that the interfacial electric field induced by the Cu−PHEO heterojunction redistributes charge density, raises the d− band center by 0.11 eV, optimizes the electronic state distribution of B sites, polarizes Li 2 S, and elongates Li−S bonds. This synergy optimizes Li 2 S adsorption (Δ E ads = −6.50 vs −4.19 eV for PHEO) and reduces its decomposition barrier to 0.94 eV, enabling ultrafast sulfur redox. The S/Cu−PHEO cathode achieves 10 C charging in 4.5 min (accompanied by a 90 min 0.5 C discharge), a 20 C ultrahigh−rate capacity of 575.2 mAh g −1 (with 0.063% decay per cycle over 1000 cycles), and faster Li 2 S oxidation kinetics. This work exemplifies how high‐entropy‐driven single‐atom anchoring (Cu↔PHEO) couples interfacial field effects with electronic tuning, providing a blueprint for designing XFC LSB electrocatalysts.