Active Oxygenated Group-Rich Polymer Electrolyte Synchronizing Bilateral Interfacial Stabilization and Accelerated...

The vision of commercializing high-energy-density solid-state lithium-oxygen batteries (SSLOBs) is hindered by poor interfacial compatibility and sluggish cathodic reaction kinetics resulting from the solid-solid contact on both sides of the solid-state electrolyte. Herein, an innovative polymerized glycidyl methacrylate (PGM) electrolyte with abundant active oxygenated groups (AOGs), that is, C═O and C─O─C, is demonstrated to synchronize bilateral interfacial compatibility and accelerated cathodic reaction kinetics for high-performance SSLOBs. Notably, the PGM modulates the Li⁺ solvation structure by expelling partial solvent molecules, inducing the formation of a dense oxide-rich solid electrolyte interphase on the Li metal anode, which suppresses dendrite growth. Theoretical calculations further elucidate that the AOGs stabilize the lithium-oxygen intermediates (e.g., LiO₂, Li₂O₂) and lower the energy barrier for Li₂O₂ decomposition, thereby accelerating oxygen reaction kinetics. Consequently, the PGM-based LOBs (PGM-LOBs) exhibit a high capacity of 13 076 mAh g^-1 at 200 mA g^-1, a low overpotential of 0.56 V, and a long life of 150 cycles (1500 h). In ambient air, PGM-LOBs maintain stable cycling for 400 h and deliver a discharge capacity of 19 044 mAh g^-1 at 200 mA g^-1. This study demonstrates a feasible AOG-rich polymer electrolyte design strategy to simultaneously improve interfacial compatibility and oxygen redox kinetics for advanced SSLOBs.