A multifunctional SnO2-nanowires/carbon composite interlayer for high-performance lithium-sulfur batteries

Abstract

Recently, lithium–sulfur (Li–S) batteries have been demonstrated as promising next-generation energy-storage devices. However, their practical application is hindered by poor cycling performance and rate capability. In this study, we prepared a multifunctional interlayer composed of SnO2 nanowires (NWs) and conductive carbon paper (CP) to enhance the electrochemical performance of Li–S batteries. This SnO2 NWs@CP interlayer could efficiently adsorb lithium polysulfides and provide electron-conductive pathways to the sulfur electrode, leading to suppression of the polysulfide shuttle effect and enhancement of the electrochemical reaction kinetics for cycling performance and rate capability. A lithium-sulfur cell fabricated with SnO2 NWs@CP interlayer at a high sulfur loading amount (ca. 4.0 mg cm−2) could deliver a high specific capacity of 815 mAh g−1 (based on sulfur) even after 100 cycles at 0.2 C with a high coulombic efficiency of 98.2%. These results demonstrate that the introduction of multifunctional SnO2 NWs@CP interlayers should be a promising new strategy for the development of high-energy-density Li–S batteries.