Scalable Solvent-Based Fabrication of Thermo-Responsive Polymer Nanocomposites for Battery Safety Regulation

TL;DR

This paper presents a scalable solvent-based method to embed thermo-responsive polymer nanocomposites into lithium-ion batteries, enhancing safety without compromising performance, and demonstrating feasibility in pouch cell manufacturing.

Contribution

It introduces a novel scalable fabrication process using tungsten carbide as a conductive filler for thermo-responsive polymers in LIBs, enabling practical high-capacity pouch cell integration.

Findings

Successful large-scale fabrication of thermo-responsive polymer nanocomposites.

Enhanced thermal abuse protection in pouch cells.

Maintained electrochemical performance in integrated cells.

Abstract

Improving lithium-ion batteries (LIBs) safety remains in a challenging task when compared with the tremendous progress made in their performance in recent years. Embedding thermo-responsive polymer switching materials (TRPS) into LIB cells has been proved to be a promising strategy to provide consistent thermal abuse protections at coin-cell level. However, it is unrealistic to achieve large-scale applications without further demonstration in high-capacity pouch cells. Here, we employed tungsten carbide (WC) as a novel conductive filler, and successfully overcame the intrinsic processing difficulty of polyethylene (PE) matrix in a scalable solvent-based method to obtain ultra-thin, uniform, highly conductive TRPS. Moreover, by integrating TRPS directly into LIB electrodes, no extra fabrication facilities or processes are required for making the cells. As a result, multi-layer pouch cells with consistent electrochemical performance and thermal abuse protection function were fabricated using industry relevant manufacturing techniques, which brings TRPS one step further to the real application scenarios.