Sulfur cathodes for sulfide electrolyte-based all-solid-sate batteries: a review

Lithium-sulfur batteries promise next-generation high-energy and low-cost battery technologies. By substitutingcon-ventional liquid ether-based electrolytes with sulfide solid-state electrolytes, all-solid-state lithium-sulfur batteries(ASSLSBs) enable sulfur redox chemistry to escape from a dilemma between reaction kinetics-required polysulfidedis-solving and resulting polysulfide shuttling. However, sulfur cathodes in sulfide-based ASSLSBs confront persistentsci-entific and technical challenges, including intrinsically sluggish reaction kinetics associated with sulfur's insulatingproperties, suboptimal solid-solid interfaces exacerbated by sulfur conversion-induced significant volume fluctuations,carbon additive-promoted electrolyte decomposition at elevated potentials, and tortuous carrier transport paths withincomposite cathodes. This comprehensive review first introduces the electrochemical mechanisms governing sulfurredox chemistry in sulfide ASSLSBs and critically analyzes the limitations of sulfur-based cathodes. We also summarizethe recent advances in developing and optimizing sulfur cathodes. Finally, we propose forward-looking perspectives onmaterial innovation and architectural optimization to guide the future development of high-performance sulfurcath-odes for practical solid-state battery applications.