Homogenous conduction: Stable multifunctional gel polymer electrolyte for lithium-sulfur batteries

Abstract

The low sulfur utilization rate and polysulfide shuttle are the main reasons that hinder the practical process of lithium-sulfur batteries. Here, an effective structural engineering strategy of multifunctional gel polymer electrolyte (GPE) by electrospinning was proposed. The HCNF@HPAN-GPE for lithium-sulfur batteries contained halloysite-base carbon nanofibers (HCNF) offered abundant active sites as sulfur fixation layer and halloysite-base polyacrylonitrile (HPAN) provided ion transport channel as ion transport layer. Both layers were abundant in the halloysite nanotubes as “transduction segment” and established the synergistic interface conduction. The HCNF@HPAN-GPE exhibited an ionic conductivity of 8.01 × 10−3 S cm−1. Therefore, the HCNF@HPAN-GPE displayed excellent interface compatibility and stabilized lithium deposition/ stripping over 800 h. Meanwhile, it demonstrated an initial discharge specific capacity of 1461.2 mA h g−1 at 0.1 C and an ultra-low-capacity attenuation of 0.056 % per cycle of 800 cycles at 1 C. In sum, this study may provide a novel strategy for the effective design of GPE toward the high performance lithium-sulfur batteries.