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Enhancing the reversibility of Li is crucial for extending the cycle life of Li‐limited anode‐free lithium–sulfur (Li–S) batteries. Incorporating tellurium (Te) in the system has proven to be highly effective by its reaction with polysulfides and forming a passivating interfacial layer on Li surface, which reduces the Li‐ion diffusion barrier. However, due to the poor utilization of Te, a significant amount of Te is required to improve cell cycling performance. To address this, nanowire‐structured Te (TeNW) is synthesized via a hydrothermal method and applied to Li₂S‐based anode‐free cells to minimize the Te content in the system while extending the cell cycle life. Coating TeNW onto the separator greatly enhances Te utilization and demonstrates a significant cycle life improvement (38% retention over 300 cycles) with only 4 wt% TeNW content relative to the active material. The versatility of TeNW is further demonstrated by utilizing them with carbon nanotubes as the anode substrate. The exceptional performance of TeNW is attributed to the high‐surface‐area nanostructure and excellent conductive network, facilitating efficient electron transfer during cell cycling. These advantageous properties position TeNW as a promising material to enhance the cycle life of Li‐limited Li–S batteries. 

Abstract The development of practical lithium–sulfur (Li–S) batteries with prolonged cycle life and high Coulombic efficiency is limited by both parasitic reactions from dissolved polysulfides and mossy lithium deposition. To address these challenges, here lithium trithiocarbonate (Li₂CS₃)‐coated lithium sulfide (Li₂S) is employed as a dual‐function cathode material to improve the cycling performance of Li–S batteries. Interestingly, at the cathode, Li₂CS₃forms an oligomer‐structured layer on the surface to suppress polysulfide shuttle. The presence of Li₂CS₃alters the conventional sulfur reaction pathway, which is supported by material characterization and density functional theory calculation. At the anode, a stable in situ solid electrolyte interphase layer with a lower Li‐ion diffusion barrier is formed on the Li‐metal surface to engender enhanced lithium plating/stripping performance upon cycling. Consequently, the obtained anode‐free full cells with Li₂CS₃exhibit a superior capacity retention of 51% over 125 cycles, whereas conventional Li₂S cells retain only 26%. This study demonstrates that Li₂CS₃inclusion is an efficient strategy for designing high‐energy‐density Li–S batteries with extended cycle life.