Abstract Lithium sulfide (Li2S) is a promising cathode for a practical lithium‐sulfur battery as it can be coupled with various safe lithium‐free anodes. However, the high activation potential (>3.5 V) together with the shuttling of lithium polysulfides (LiPSs) bottleneck its practical uses. We are trying to present a catalysis solution to solve both problems simultaneously, specially with twinborn heterostructure to shoot off the trouble in interfacial contact between two solids, catalyst and Li2S. As a typical example, a Co9S8/Li2S heterostructure is reported here as a novel self‐catalytic cathode through a co‐recrystallization followed by a one‐step carbothermic conversion. Co9S8 as the catalyst effectively lowers the Li2S activation potential (