Enabling Durable Quasi-Solid-State Li–S Batteries with an Organic Nitrate Additive for Anode Protection and Polysulfide Confinement

), as verified through X-ray photoelectron spectroscopy (XPS) analysis and theoretical calculations. The reinforced SEI enhances interfacial ion transport and mechanical robustness, thereby achieving uniform and dendrite-free lithium deposition. Density functional theory (DFT) calculations further reveal strong chemical interactions between ISDN and PDOL, which effectively enhance the adsorption of polysulfide onto PDOL to suppress the shuttle effect. Benefiting from these synergistic functions, Li|PDOL@ISDN|Li symmetric cells achieve stable cycling exceeding 1000 h without short-circuit failure. Quasi-solid-state Li-S batteries also demonstrate excellent cycling stability, with a capacity retention of 84.7% after 100 cycles at 0.2C. This work offers a promising strategy for designing high-performance solid-state Li-S batteries based on PDOL electrolytes.