Regulating Li2S Deposition and Accelerating Conversion Kinetics through Intracavity ZnS toward Low-Temperature Lithium–Sulfur Batteries

The uncontrolled deposition behavior and sluggish conversion kinetics of the discharging product (solid Li₂S) severely deteriorate the electrochemical performance of lithium-sulfur (Li-S) batteries, especially under high S loading and low-temperature conditions. Herein, a multifunctional S cathode host consisting of ZnS nanoparticles (NPs) confined in hollow porous carbon spheres (ZnS@HPCS) is synthesized via a unique capillary force-driven melting-diffusion strategy. The porous carbon shell of ZnS@HPCS provides a space-confined reservoir for soluble polysulfides and solid Li₂S, while the intracavity ZnS NPs trap polysulfides, induce Li₂S inside deposition, and accelerate conversion kinetics. Thus, Li-S batteries with ZnS@HPCS-S cathodes exhibit excellent electrochemical performance at both room and low temperatures (-40 °C) and high reversible capacities under high S loading (5.2 mg cm^-2). Furthermore, Li₂S nucleation/deposition, in situ Raman, and theoretical analyses reveal the underlying mechanism. This work offers fundamental insights into regulating Li₂S deposition and designing S hosts for high-performance Li-S batteries.