Ionic Liquids Anchored on Carbon Synchronize Ion-Electron Transport in Liquid- and Solid-State Sulfur Batteries

Sulfur-based batteries hold great promise for next-generation energy storage owing to their high capacity and low cost, yet their performance is limited by sluggish ion transport and insulating discharge products. Here, we construct a continuous mixed ion-electron conductor network by anchoring imidazolium-based ionic liquids onto carbon nanotubes via strong π-π interactions. The ionic liquid layers provide fast Li + pathways along the conductive framework, enabling synchronized ion–electron transport and reducing the Li 2 S nucleation overpotential to 28.2 mV. This interfacial design accelerates sulfur conversion and delivers outstanding cycling stability over 1000 cycles with only 0.045% capacity decay per cycle. In addition, PEO-based solid-state cells can also exhibit high sulfur utilization (>80%) and robust durability. Ah-level pouch cells achieve 1.7 Ah and 379 Wh kg –1 demonstrating that ionic liquid-anchored carbons offer a scalable strategy toward practical, high-energy lithium–sulfur batteries.