A sulfur-rich polymeric cathode for high-capacity lithium-sulfur battery

Lithium-sulfur (Li−S) batteries offer promising potential as next-generation energy storage systems due to their high theoretical energy density, cost-effectiveness, and eco-friendliness. However, the main challenges, including low sulfur utilization, poor cycling stability, and the polysulfide shuttle effect, have hindered their practical applications. In this study, we report a novel sulfur-rich polymeric cathode material by hybridizing two organic sulfur-containing polymers, one providing a conductive polymeric backbone with some sulfur bonding sites and the other providing extended sulfur bonding sites and sulfur chain lengths. The resulting cathode materials effectively increased the overall sulfur content to 59.6 wt%, while maintaining a stable cathode-electrolyte interphase (CEI) that enables stable long-term cycling. As a result, this cathode delivers a high specific capacity of 766.6 mAh g –1 and excellent cycling stability with 85.9% retention after 300 cycles. Pouch cells with a high areal capacity of 4.5 mAh cm –2 under lean electrolyte and limited lithium conditions were demonstrated, highlighting its promising potential for practical applications.