Structural and Chemical Channel Engineering Enables Regulated Cation‐Anion Kinetics in Crystalline Quasi Solid Electrolytes

ABSTRACT Regulating the transport kinetics of lithium salt cations and anions within the confined pores of metal organic framework (MOF) quasi solid‐state electrolytes is essential for improving ionic conductivity and electrochemical stability of battery, yet remains challenging. Here, we synthesize two porous anionic hybrid azolate frameworks (AHF‐1‐H and AHF‐2‐H) by introducing linear and non‐linear carboxylate ligands to modulate pore geometry. In AHF‐2‐H, distorted 1D channels provide an optimized conduction pathway for Li + transport. Furthermore, three functional groups (─NH 2 , ─OH, ─CH 3 ) are incorporated into AHF‐2‐X to tailor the local electronic structure and surface chemistry within the channels. The introduction of ─NH 2 groups effectively immobilizes Bis(trifluoromethanesulfonyl)imide anion (TFSI − ) anions and promotes their dissociation, thereby enhancing lithium‐ion mobility and granting this material the highest ionic conductivity within the series. Furthermore, it induces the formation of a LiF‐rich layer at the lithium metal interface, which not only suppresses lithium dendrite growth and persistent electrolyte decomposition but also significantly improves cycling stability. Quasi solid‐state LiFePO 4 ||Li cells employing AHF‐2─NH 2 exhibit excellent cycling stability, delivering 149.7 mAh g −1 after 100 cycles at 0.5 C. This work establishes a structural chemical co‐engineering strategy for designing porous crystalline frameworks as high‐performance quasi solid‐state electrolytes.