Modulating Electron Delocalization Structure in Covalent Organic Frameworks Through Conjugation and Hybridization to Boost Li‐ion Migration Dynamics

Abstract

ABSTRACT The inherent factors influencing the growth of lithium (Li) dendrites and the kinetics of Li + migration in polymer electrolytes lie in the electron cloud density distribution in the electrolyte. Localized electrons accumulation can trigger the uneven Li + deposition, ultimately leading to battery failure. To address this critical challenge, the concept of p–π conjugation and B–O sp 2 hybridization is innovatively incorporated into covalent organic frameworks (COFs) to mitigate local interfacial Li + accumulation and improve Li + migration kinetics in electrolytes by electron delocalization. Furthermore, perfluoroalkyl group with virtues of superior electron regulating capabilities and improved electrochemical‐window, is strategically grafted to better match high‐voltage cathodes. Under the synergistic role of electron regulation, the electrolyte with pπ–sp 2 ‐COF significantly improves overall electrochemical performance of solid‐state batteries. Thus, regulating electron density via p‐π conjugation and B‐O sp 2 hybridization promises to open new avenues for the development of COFs‐modified polymer electrolytes in solid‐state batteries.