Vacancy occupation-phase transformation synergistic regulation toward high-performance lithium-sulfur batteries

Lithium‑sulfur (Li[sbnd]S) batteries have attracted considerable attention due to their high theoretical energy density and environmental friendliness. However, their practical applications are limited by the shuttle effect and sluggish conversion kinetics. In this work, we successfully design and precisely construct o-CoTe₂|P nanoparticles on a 3D ordered porous carbon matrix from the perspective of “vacancy occupation-phase transformation coupling” for efficient and durable Li[sbnd]S batteries. DFT theoretical calculations demonstrate that the o-CoTe₂|P not only facilitates the redistribution of local charges, forming efficient adsorption sites for anchoring LiPSs, but also optimizes electronic transport pathways, significantly reducing the energy barrier. Thus, it achieves the synergistic regulation of the “anchoring-diffusion-conversion” process of sulfur species. Electrochemical results demonstrate that the o-CoTe₂|P@S cathode exhibits an extremely high initial specific capacity of 1237.72 mAh g⁻¹ at 0.2C and an ultralow capacity decay rate of 0.038 % per cycle with 1000 cycles at 4C. Furthermore, the flexible pouch cell with precisely integrated GPE and copper mesh-reinforced flexible Li-metal composite anode demonstrates superior mechanical and safety properties. This study provides valuable insights into the rational design of electrocatalysts for advanced Li[sbnd]S batteries.