The Polymer Society of Korea

Abstract

Lithium (Li)-metal batteries (LMBs) are considered a great candidate to enhance energy density by utilizing metallic Li electrodes. On the other hand, the irregular Li⁺ transport and subsequent dendrite formation must be resolved. The regulating Li⁺ flux by pore size control was only observed in the <5 nm or >20 nm region, thus limiting the exploration of critical Li⁺ transport phenomena and their impact on improving cell performance. Here, we propose a 3D continuous, functional mesoporous polymer membrane with controllable pore size, synthesized by polymerization-induced microphase separation. Introducing a negatively charged sulfonate group to the pore surface, the Li⁺ conductivity can be increased, and side reactions on the surface of the lithium electrode through negative ions can be suppressed. This separator enhances Li⁺ mobility compared to the counteranion, reducing interfacial resistance and promoting uniform Li deposition, resulting in long cyclability.