Integrated reactor architecture of conductive network and catalytic nodes to accelerate polysulfide conversion for durable and high-loading Li-S batteries

Abstract

The development of carbon-based heterogeneous framework host with synergistic catalytic and conductive effects for sulfur cathode is a promising strategy to realize high performance lithium sulfur batteries (LSBs). Here, an integrated reactor architecture with defective carbon nodes (IRA-DC) is designed for serving as high-loading (92.4 wt%) sulfur host. The hierarchical porous IRA-DC consists of untangled conductive carbon nanotube network and Co/N co-doped catalytic nodes with high dispersity. Therein the optimization of electric field distribution and homogenization of adsorption-catalysis sites offer the multi-electron conversion reaction of polysulfides with excellent kinetics and stability. The resultant IRA-DC/S cathode enables a high areal capacity of 8.86 mAh cm−2 under ultra-high sulfur loading (13.1 mg cm−2) and lean electrolyte (8 μL mgsulfur−1). It also displays a long-term cycling performance (1200 cycles at 1 C) and ultrahigh rate performance up to 20 C (with a capacity of 473.6 mAh g−1). This work provides an electrode building strategy by optimizing the environments of heterogeneous electrocatalysis and micro electric field to activate the polysulfide conversion efficiency and utilization of high-loading sulfur in monolithic sulfur-carbon cathodes.