Cascade Desolvation and Conversion Reaction Driven by Self-Tandem Catalysis for Wide-Temperature Li-S Batteries

Dissatisfactory electrochemical performance of wide-temperature lithium-sulfur batteries (LSBs) originates from the sluggish Li⁺ desolvation and successive sulfur specie conversion kinetics at the interface and within the cathode interior. Herein, different from electrolyte engineering, a self-tandem catalysis enabled cascade reactions is developed to drive Li⁺ kinetics and associated polysulfide conversions in wide-temperature LSBs. By incorporating electron-adjustable atom-level Ce as the self-tandem catalyst onto defect-rich Co, Fe-based layered double hydroxides (EAAC@D-LDH), a favorable solvation microenvironment is established to decrease the related barriers toward promoting rapid Li⁺ desolvation, sulfur conversion, and Li₂S delithiation kinetics, as revealed in Raman analysis, electrochemical evaluations, and ex-situ interfacial morphology as well as composition characterization. Such improved reaction kinetics enable the sulfur cathodes work well in a wide temperature ranging from 0 to -30°C, and it retains high-capacity retention of 94% at 5C. Under -20°C, the cells remain the capacity of 85% at 0.1C, respectively. Remarkably, a stable capacity is reserved even at an ultralow temperature of -30°C, demonstrating that the substantial promise of this self-tandem catalysis supports cascade reaction refinement strategy toward high performance wide-temperature LSBs.