The Polymer Society of Korea

Abstract

High-performance lithium-ion batteries require large-scale separator fabrication that simultaneously provides high production efficiency, thermal stability, and mechanical robustness. In this study, we proposed a scalable fabrication strategy for a nonwoven nanofiber web-based polyimide (PI) separator by combining syringeless electrospinning with a roll-pressing process. Syringeless electrospinning enabled the fabrication of large-area nonwoven membranes, while roll pressing effectively controlled the porosity and density of the membrane. The resulting PI-based nonwoven membrane exhibited excellent mechanical strength and thermal stability, along with enhanced electrolyte affinity, leading to high ionic conductivity and an increased lithium-ion transference number. Finally, the electrochemical performance of the separator was evaluated in the NCM622//graphite full cell, demonstrating its potential for high-performance lithium-ion battery applications.