Phase Reconstruction‐Assisted Electron‐Li⁺ Reservoirs Enable High‐Performance Li‐S Battery Operation Across Wide Temperature Range

Abstract Lithium‐sulfur batteries (LSBs) are known as high energy density, but their performance deteriorates sharply under high/low‐temperature surroundings, due to the sluggish kinetics of sulfur redox conversion and Li⁺ transport. Herein, a catalytic strategy of phase reconstruction with abundant “electron‐Li⁺” reservoirs has been proposed to simultaneously regulate electron and Li⁺ exchange. As a demo, the 1T‐phase lithiation molybdenum disulfide grown on hollow carbon nitride (1T‐Li_xMoS₂/HC₃N₄) is achieved via in situ electrochemical modulation, where the 1T‐Li_xMoS₂ serves as an auxiliary “Li⁺ source” for facilitating Li⁺ transport and the HC₃N₄ acts as an electron donor for electronic supplier. From the theoretical calculations, experimental and post‐modern analyses, the relationship between the catalytic behaviors and mechanism of “electron‐Li⁺” reservoirs in accelerating the rate‐determining kinetics of sulfur species are deeply understood. Consequently, the cells with 1T‐Li_xMoS₂/HC₃N₄/PP functional separator demonstrate excellent long‐term electrochemical performance and stabilize the areal capacity of 6 mAh cm⁻² under 5.0 mg cm⁻². Even exposed to robust surroundings from high (60 °C) to low (0 °C) temperatures, the optimized cells exhibit high‐capacity retention of 76.2% and 90.4% after 100 cycles, respectively, pointing out the potential application of catalysts with phase reconstruction‐assisted “electron‐Li⁺” reservoirs in LSBs.