Challenges and rational design approaches of high-energy-density rechargeable zinc-sulfur batteries

Abstract

Rechargeable zinc-sulfur (Zn-S) batteries have attracted considerable attention owing to their advantages of low cost, high safety, and high energy density. Despite facing critical challenges such as low electrical conductivity, sluggish reaction kinetics, and polysulfide shuttle effect, the latest advancements in active material design and electrolyte engineering have brought about significant breakthroughs. In this review, we first delve into the electrochemistry differences and key challenges of Zn-S batteries in both aqueous and nonaqueous electrolyte systems. Then, several effective approaches at the cathode side, including electrocatalytic function, host architecture design, selenium/tellurium incorporating, hybrid configuration with Cu²⁺ charge carrier, and electrolyte engineering, are summarized to improve reaction kinetics and cycling stability. Further breakthroughs will rely on integrating S structure/morphology regulation, interface design, anode optimization and multi-scale characterizations. This review contributes to more comprehensive understanding in the reaction mechanisms and constructive strategies, which is expected to further facilitate the rapid development and practical application of high-energy-density Zn-S batteries.