A Hierarchically Porous Multifunctional Current Collector for High-Performance Li-S Batteries

Construction of an advanced current collector with optimized structure and multi-functionality is critical for solving the thorny problems (e.g., lithium polysulfides (LiPSs) shuttle effect, low conductivity, and sluggish sulfur conversion) of Li-S batteries. Unlike the use of an conventional pore-free 2D current collector (low sulfur loading) or the 3D current collector rich in irregular macropores (poor sulfur fixation ability), herein a hierarchically porous current collector (HPCC) with tailored pore architecture and multifunctionality is designed, which is constituted by a large-pore 3D carbon cloth (CC) substrate (pore size > 50 µm), conjugated microporous conducting polymers (CMPs) filler materials (pore size 0.8–1.6 nm) and Pd nanopaticle catalysts (3–5 nm). The HPCC optimizes the original large-pore 3D CC structure into a hierarchically porous structure with regularized pore size and uniform catalytic sites, achieving a 2D/3D functional balance. Benefiting from the enhanced Li⁺/e⁻ transportation, high-efficiency LiPSs adsorption, and strong catalysis ability for LiPSs, the batteries with HPCC achieve the ultrahigh discharging capacity of 1304 mAh g⁻¹ at 0.2 C, exceptional stability (0.42% decay/cycle at 10.59 mA·cm⁻²) even at a high sulfur loading condition of 10.3 mg cm⁻², and good commercial application potential (driving electric-car operation). This pore engineering strategy establishes a paradigm for developing a high-energy-density battery.