Rational Design of High-Loading Sulfur Cathodes with a Poached-Egg-Shaped Architecture for Long-Cycle Lithium–Sulfur Batteries

A high-loading electrode is essential for establishing high-energy-density lithium–sulfur (Li–S) batteries, but it is confronted with critical challenges. Herein, we present a free-standing poached-egg-shaped architecture through a facile template-supported vacuum-filtration strategy and employ it as an efficient sulfur host for Li–S batteries. This unique architecture guarantees an effective encapsulation of the “sulfur yolk” inside the fully vacuum-sealed framework, effectively limiting the active material loss and polysulfide diffusion. Also, the conductive and porous framework serves as an interlinked electron pathway and electrolyte channel, greatly facilitating fast electric/ionic transport along with active material reactivation and reutilization during cycling. A high peak discharge capacity (1200 mA h g –1 ), a low capacity-fade rate (0.09% cycle –1 ) for 500 cycles, and excellent rate capability (C/5–1C rates) are accomplished. Moreover, with such an advantageous architecture, the sulfur loading is successfully increased to 32 mg cm –2 to achieve an areal capacity of up to 16 mA h cm –2 . This work provides guidelines for realizing optimized high-loading Li–S batteries.