Synergistic Regulation of Single-Atom Catalysis and Conductive Enhancement in All-Solid-State Li–S Batteries

The electrochemical performance of all-solid-state lithium–sulfur batteries (ASSLSBs) remains inadequate for commercial viability due to the inherently low electronic conductivity of elemental sulfur, which results in sluggish reaction kinetics. Here, we propose a dual modification strategy combining doping and catalysis to promote solid-state conversion reactions in the sulfur cathode. This synergistic approach has been shown to enhance the electrical conductivity of the sulfur cathode, thereby improving the reaction kinetics. Through XPS and 7Li ssNMR analysis, we reveal the sequential formation and quantitative evolution of various lithium polysulfide intermediates during the sulfur reduction process. The ASSLSBs demonstrated an areal capacity of 6.3 mAh cm–2 and a capacity retention of 95.9% after 100 cycles. Furthermore, the ASSLSBs paired with a Li metal anode achieved an electrode energy density of 818.4 Wh kg–1. These findings provide valuable insights into the solid-phase conversion process of sulfur and establish a promising strategy for developing high-performance ASSLSBs.