Regulation of Lithium-Ion Flux by Nanotopology Lithiophilic Boron-Oxygen Dipole in Solid Polymer Electrolytes for Lithium-Metal Batteries

Inhomogeneous lithium-ion (Li+) deposition is one of the most crucial problems, which severely deteriorates the performance of solid-state lithium metal batteries (LMBs). Herein, we discovered that covalent organic framework (COF-1) with periodically arranged boron-oxygen dipole lithiophilic sites could directionally guide Li+ even deposition in asymmetric solid polymer electrolytes. This in situ prepared 3D cross-linked network Poly(ACMO-MBA) hybrid electrolyte simultaneously delivers outstanding ionic conductivity (1.02 x 10(-3) S cm(-1) at 30 & DEG;C) and excellent mechanical property (3.5 MPa). The defined nanosized channel in COF-1 selectively conducts Li+ increasing Li+ transference number to 0.67. Besides, The COF-1 layer and Poly(ACMO-MBA) also participate in forming a boron-rich and nitrogen-rich solid electrolyte interface to further improve the interfacial stability. The Li||Li symmetric cell exhibits remarkable cyclic stability over 1000 h. The Li||NCM523 full cell also delivers an outstanding lifespan over 400 cycles. Moreover, the Li||LiFePO4 full cell stably cycles with a capacity retention of 85% after 500 cycles. the Li||LiFePO4 pouch full exhibits excellent safety performance under pierced and cut conditions. This work thereby further broadens and complements the application of COF materials in polymer electrolyte for dendrite-free and high-energy-density solid-state LMBs.