Silver Embedded Electrospun Nanofibers as an Efficient Interlayers for High-Performance Practical Li-S Batteries

This study presents a practical approach for the synthesis of Ag nanoparticle-containing polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) nanofibers from AgNO₃-doped PVA and PVP precursor solutions at ambient temperature. The prepared nanofibers were coated on the glass fiber separator as efficient interlayers for long-cycle life Li-S batteries. The initial specific capacity of the cell with Ag@PVP composite is 1201 mAh g⁻¹. During the first 500 cycles, the specific capacity retains at 998 mAh g⁻¹. The specific capacity of Ag@PVA remains at 793 mAh g⁻¹, resulting in a lower capacity retention rate compared to Ag@PVP after 500 cycles. The best result was achieved by Ag@PVP, which exhibited a capacity retention rate of ≈83% and maintained a coulombic efficiency of 99%, indicating superior cycling stability even after 500 cycles. In addition, the Ag@PVA composite achieved a capacity retention rate of ≈80% and maintained a coulombic efficiency of 97.5% after 500 cycles. The incorporation of highly conductive Ag into the polymer structure can effectively reduce the shuttling effect by enhancing the chemical interactions between polysulfides and modified interlayers. Ag@PVP and Ag@PVA on glass fiber separators can improve cycling stability over long periods of time, making them promising candidates for use in scalable and practical Li-S batteries.