Rational design of bidirectional sandwich structure with etched aluminum and carbon cloth for high-performance lithium-sulfur batteries

Lithium-sulfur (Li–S) batteries are promising energy storage systems with low-cost, high-energy density and environment-friendly characteristics. Nevertheless, there are still some issues that need to be settled in practical applications, such as the migration and shuttle effect of polysulfides, the poor conductivity of sulfur, and serious volume expansions in the cycling process. To overcome these challenges, we herein assemble a bidirectional 3D sandwich structured Li–S battery with an etched porous Al current collector and a conductive carbon cloth (CC) interlayer. The sandwich structure endows the Li–S battery with a high reversible capacity, low-capacity decay, good coulombic efficiency. In addition, the battery presents a competitive energy density of 1000 Wh kg⁻¹ _-S and 200 Wh kg⁻¹ _-cathode with a mass loading of 1.0 mg cm⁻² at 1 C. Due to the remarkable electrochemical performance, the sandwich structure provides a potential for large-scale industrial production of Li–S batteries.