Anode/Electrolyte Interfacial Engineering Toward Sustainable and Practical Solid‐State Metal‐Sulfur Batteries: A Prospective Review

Solid‐state metal‐sulfur batteries are emerging as a transformative energy storage platform with the potential to overcome the fundamental limitations of conventional flooded cells, particularly polysulfide shuttling and uncontrolled anodic evolution. In addition to mitigating these issues, solid‐state configurations offer enhanced safety, superior electrochemical stability, and an exceptionally high theoretical energy density of 2600 Wh kg −1 . Nevertheless, the theoretical potential of solid‐state metal‐sulfur batteries is critically hindered by the instability of the anode/electrolyte interfaces. Pronounced metal dendrite growth, interfacial contact loss, and chemo‐mechanical degradation can synergistically deteriorate interfacial integrity and ultimately govern cell performance and lifespan. In this review, we first outline the state of the art in anode metals and solid‐state electrolytes employed in metal‐sulfur batteries, emphasizing their fundamental properties and inherent challenges. We then systematically survey recent advances on anode/electrolyte interfacial engineering strategies for solid‐state metal‐sulfur batteries, encompassing anodic surface modification, electrolyte composition and structural optimization, and rational interlayer design. Finally, we propose key design principles for next‐generation interfacial materials capable of simultaneously enhancing ionic and electronic transport, alongside advanced characterization techniques and multiscale simulations aimed at elucidating interfacial mechanisms and ensemble effects. Toward practical implementation, we further discuss perspectives on achieving deeply reversible, compatible metal anodes to enable stable, scalable, and cost‐effective next‐generation solid metal‐sulfur batteries.