Synergistic Enhancement to Polysulfide Catalytic Conversion and Lithium Dendrite Resistant by 3D Cross‐Linked Fe‐N ₄ ‐GCs for Stable Lithium‐Sulfur Batteries of Low‐N/P‐Ratio

ABSTRACT The severe shuttle effect and sluggish reaction kinetics of lithium polysulfides (LiPSs) as well as Li dendrite growth are still the key issues for lithium‐sulfur batteries (LSBs). Herein, atomically dispersed Fe‐N ₄ moieties anchored on 3D cross‐linked N‐doped graphene‐like porous carbon nanosheets (Fe‐N ₄ ‐GCs) as efficient LiPSs catalyst and Li regulator for high‐performance LSBs is reported. Serving as sulfur host, Fe‐N ₄ ‐GCs provide abundant adsorption sites and effectively catalyze LiPSs conversion. As separator coating, they form uniform Li ⁺ transport channels, promote fast ion diffusion, and guide stable Li plating/stripping to suppress dendrite growth. With S/Fe‐N ₄ ‐GCs cathode (2.5 mg cm ⁻² S) and Fe‐N ₄ ‐GCs/PP separator, LSB delivers a high initial capacity of 1045.6 mAh g ⁻¹ at 1.0 C, along with stable cycling over 1000 cycles with a low decay of 0.023% per cycle. At a high S loading of 7.2 mg cm ⁻² , an areal capacity of 6.6 mAh cm ⁻² is achieved. Remarkably, a full cell using Cu@Li anode (27 µm Li layer) with a low N/P ratio of 1.3 retains a high capacity of 1025.8 mAh g ⁻¹ at 1.0 C and stable cycling over 400 cycles with a low decay of 0.026% per cycle. This work offers an effective strategy toward high‐energy, long‐life LSBs.