Operando Observation of Inter‐Particle Li + Transport in Layered Bimetallic Sulfides for High‐Rate Lithium‐Sulfur Batteries

ABSTRACT The slow reaction kinetics, particularly at high rates, hinder the practical use of lithium‐sulfur batteries (LSBs). To overcome the inadequate ion transport in conventional electrodes, a two‐dimensional layered bimetallic sulfide (FeMo 2 S 4 ) as a sulfur host, creating fast ion‐conduction pathways is developed. Using a free‐standing FeMo 2 S 4 /carbon cloth cathode with a Li 2 S 6 catholyte, high‐rate performance is achieved. Crucially, in situ high‐resolution TEM directly visualized rapid inter‐particle lithium ion transport between the layered FeMo 2 S 4 flakes, offering direct evidence of enhanced kinetics. This phenomenon, combined with strong polysulfide adsorption and high catalytic activity, boosts reaction rates. The Li 2 S 6 ‐based battery delivered a high initial capacity of 1516 mAh g − 1 and outstanding stability with only 0.028% decay per cycle at 3C. This work highlights the effectiveness of layered hosts with fast ion channels and bimetallic catalysis for durable, high‐rate LSBs.