Steering Isotropic Li ₂ S Growth via Bi‐Metallic Coupling: d ‐State Reengineering for Durable Li‐S Batteries

Uncontrolled Li 2 S accumulation and high nucleation barriers severely hinder the sulfur utilization and cycle lifespan of lithium‐sulfur batteries (LSBs). Herein, we report an advanced bimetallic Mo 2 V 2 C 3 T x MXene as a functional separator modifier designed to accelerate the Li 2 S nucleation and growth kinetics. Compared with V 4 C 3 T x , strategic substitution of Mo 2+ effectively modulates the d ‐orbital occupancy of V 2+ centers. This electronic reconfiguration drives an upshift of the d ‐band center toward the Fermi level, accompanied by a significant broadening of the d ‐band. Theoretical calculations combined with in situ analyses reveal that the unique Mo‐V bimetallic coupling induces d ‐orbital delocalization, which strengthens d‐p orbital hybridization between the Mo 2 V 2 C 3 T x and polysulfides, ultimately achieving an isotropic electric field distribution. This precise modulation dictates the Li 2 S deposition morphology, facilitating the isotropic growth of ultra‐uniform 3D spheres while maintaining high interfacial Li + flux. Consequently, the full battery exhibits a low‐capacity fading rate of 0.017% per cycle after 1500 cycles at 2 C. Even under a high sulfur loading of 6.8 mg cm −2 , the cell retains 92.1 of its initial capacity over 200 cycles at 1 C. This work establishes a new paradigm for the structure‐property relationship between Li 2 S deposition morphology and electrochemical performance by employing a bimetallic coupling strategy.