Nanofiber‐Confined 2H‐NbSe ₂ With a Li ₂ S Activation Interface for 10 C Fast‐Charging Lithium–Sulfur Batteries

ABSTRACT The uncontrolled shuttle of lithium polysulfides (LiPSs) and sluggish Li 2 S conversion kinetics critically limits the high‐rate performance of lithium–sulfur (Li–S) batteries. To overcome this, a flexible carbon nanofiber‐confined 2H‐NbSe 2 membrane (2H‐NbSe 2 @CNFM) is developed as an electrocatalytic membrane reactor (NS@MR) to construct a Li 2 S activation interface for precise modulation of terminal sulfur species. The ABA‐stacked layered structure of 2H‐NbSe 2 enables strong Li–Se interactions and orbital hybridization, thereby enhancing LiPSs adsorption. Simultaneously, delocalized Nb d‐electrons and anisotropic Se–Se channels facilitate electron and Li + transport while lowering the nucleation and decomposition barriers of Li 2 S. In situ XRD and Raman characterizations confirm the bidirectional catalytic capability of the activation interface in promoting efficient Li 2 S precipitation and dissolution. Consequently, the NS@MR‐modified Li–S battery delivers a 27.6% increase in sulfur utilization at 0.2 C and achieves 608.2 mAh g −1 at 10 C. A high areal capacity of 5.27 mAh cm −2 is obtained in pouch cells with a 4.4 mg cm −2 sulfur loading. Moreover, two such cells in series successfully power a 61‐LED array. This work offers atomic‐level insights into catalytic interface design for high‐power Li–S batteries.