Directional Ion Transport Enabled by Self-Luminous Framework for High-Performance Quasi-Solid-State Lithium Metal Batteries

Composite gel polymer electrolyte (CGPE), derived from ceramic fillers has emerged as one of the most promising candidates to improve the safety and cycling stability of lithium metal batteries. However, the poor interface compatibility between the ceramic phase and polymer phase in CGPE severely deteriorates lithium-ion pathways and cell performances. In this work, a fluorescent ceramic nanowire network that can palliate the energy barrier of photoinitiators and contribute to preferential nucleation and growth of polymer monomers is developed, thus inducing polymer segment orderly arrangement and tightly combination. A proof-of-concept study lies on fabrications of poly(ethylene oxide) closely coating on the ceramic nanowires, thus dividing the matrix into mesh units that contribute to directional lithium-ion flux and dendrite-free deposition on the metallic anode. The CGPE, based on the state-of-the-art self-luminous framework, facilitates high-performance quasi-solid-state Li||LiFePO4 cell, registering a high capacity of 143.3 mAh g(-1) after 120 cycles at a mass loading of 12 mg cm(-2). X-ray computed tomography provides an insight into the relationship between directional lithium-ion diffusion and lithium deposition behavior over the electrochemical processes. The results open a door to improve the electrochemical performances of composite electrolytes in various applications.

Automated summary

This study develops a fluorescent ceramic nanowire network to improve the performance of composite gel polymer electrolyte (CGPE) by palliating energy barriers and promoting selective nucleation and growth of polymer monomers. The results demonstrate that CGPE based on the self-luminous framework can achieve high-performance lithium metal batteries.