Sulfur‐Rich Polymers with Functional Linkers for High‐Capacity and Fast‐Charging Lithium–Sulfur Batteries

Abstract Pressing challenges facing future lithium batteries include the realization of a high specific capacity, reliable cycle life, fast charging, and improved safety. Herein, cutting‐edge lithium–sulfur batteries based on sulfur‐rich polymers that demonstrate a high discharge capacity of 1346 mAh g −1 at 0.1C, a record‐high rate performance of 833 mAh g −1 at 10C, and long lifetime of 500 cycles with a low capacity decay of 0.052% per cycle are reported. These are realized via the linker‐controlled mass synthesis of sulfur‐rich polymers with the possible tuning of charge transfer properties and effective suppression of the polysulfide‐shuttle via chemical interactions. In particular, the use of tetra(allyloxy)‐1,4‐benzoquinone linker enables the conductivity enhancement by a factor of 450 and lithium diffusion kinetics improvement by two orders of magnitude during redox reactions, compared with elemental sulfur cathodes. This work overcomes fundamental limitations of organosulfur cathode materials, and could pave the way for the development of next‐generation lithium batteries.