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

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 x MoS 2 /HC 3 N 4 ) is achieved via in situ electrochemical modulation, where the 1T‐Li x MoS 2 serves as an auxiliary “Li + source” for facilitating Li + transport and the HC 3 N 4 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 x MoS 2 /HC 3 N 4 /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.