A Composited Interlayer with Dual‐Effect Trap and Repulsion for Inhibition of Polysulfides in Lithium‐Sulfur Batteries

Abstract

AbstractThe shuttle effect of polysulfides in lithium‐sulfur batteries (LSBs) is the biggest obstacle for their practical application. Inserting a composite interlayer between the cathode and separator to solve the problem is a simple and effective strategy. Polyethylene oxide (PEO) is a suitable choice for trapping polysulfides, owing to its strong dipole‐dipole interaction with polysulfides. In addition, in order to enhances the inhibitory effect of the composite interlayer on the polysulfide shuttling, the addition of negatively charged sodium lignosulfonate (SL) into the composite interlayer can effectively repel the polysulfide, thus achieving a dual‐effect inhibition on the shuttle effect together with PEO, and obtaining better cell performances. Furthermore, owing to the addition of PEO and SL, the physical and electrochemical performances have been significantly improved, including, but not limited to, the liquid electrolyte uptake (251.5 wt %), ionic conductivity (5.9×10−4 S cm−1), and lithium transferences number (0.61). Therefore, this is a simple and effective strategy to prepare composite interlayer with PEO and SL to achieve dual‐effect suppression of the shuttle effect in LSBs.