Robust Adaptive Interphases via Dual Regulation of Solvation and Molecular Armor for Long‐Life Ni‐Rich Quasi‐Solid‐State Batteries

ABSTRACT The advancement of nickel‐rich lithium metal batteries is significantly impeded by the trade‐off between ion transport efficiency and electrode/electrolyte interfacial stability. To overcome this limitation, we introduce a 9‐µm‐thick composite quasi‐solid electrolyte MLZPE based on a molecular‐armor‐mediated solvation engineering strategy. MLZPE features a three‐dimensional interpenetrating network in which nanosuperacid ZrO 2 ‐SO 4 2− preferentially interacts with ethylene carbonate to weaken Li + ‐solvent coordination, thereby increasing the Li + transference number to 0.698 and raising the ionic conductivity to 0.107 mS/cm. Simultaneously, in‐situ polymerized poly(N, N'‐methylene bisacrylamide) (PMBA) forms a dense passivation layer that chemically anchors onto the superacid surface, suppressing electrolyte decomposition. Together with poly(vinylidene fluoride‐co‐hexafluoropropylene) (P(VDF‐HFP)), PMBA promotes the formation of interphases enriched with LiF and Li 3 N. in‐situ impedance spectroscopy reveals that these interphases undergo reversible reconstruction during cycling, indicating adaptive and self‐healing characteristics. As a result, the NCM83||Li quasi‐solid‐state cell achieves 92.6% capacity retention after 200 cycles at 0.5 C. This work demonstrates a synergistic design that concurrently achieves rapid ion transport and durable interfacial stability, providing a viable route to high‐energy, long‐cycle‐life nickel‐rich quasi‐solid‐state batteries.