“Like Compatible Like” Strategy Designing Strong Cathode‐Electrolyte Interface Quasi‐Solid‐State Lithium–Sulfur Batteries

Abstract Gel polymer electrolytes (GPE) have stimulated the enthusiasm to develop high‐performance quasi‐solid‐state lithium–sulfur (Li–S) batteries, but the incompatibility between non‐polar sulfur cathode and polar GPE has limited its further development. Changing polarity by replacing the non‐polar sulfur cathode to polar organosulfur cathode is expected to improve the cathode‐electrolyte interface compatibility. Inspired by “like compatible like” strategy, a vinyl‐capped hyperbranched polymer network (PEI‐GMA) is developed that serves as a backbone structure for both organosulfur polymer cathode (G/PEI‐GMA@S) and GPE to construct a strong cathode‐electrolyte interface. High interfacial compatibility contributes to accelerating electron/ion conduction for superior transfer kinetics and construction of stable quasi‐solid‐state Li–S batteries. As a result, the internal resistance of the battery is significantly reduced by 60%, and after 400 cycles, the battery capacity retention rate is 91%, with an average decay rate per cycle as low as 0.022%. Meanwhile, the strategy of optimizing both cathodes and electrolytes without design multiple materials makes Li–S batteries more competitive in practical applications. This study emphasizes the importance of moderating relevant polarity for constructing a strong cathode‐electrolyte interface, which provides guiding principles for the electrode and electrolyte design of advanced Li–S batteries.