# Effect of Non-Woven Backing on Support PVDF Membranes for Acidic Electrochemical Applications

## TL;DR

This paper investigates how non-woven backing affects the performance of PVDF membranes in acidic electrochemical applications like batteries.

## Contribution

The study compares commercial non-woven substrates and evaluates their suitability for electrochemical use, highlighting resistance limitations.

## Key findings

- Non-woven substrates have high area resistance (0.37–1.47 ohm.cm2), limiting their use in electrochemical applications.
- Woven fabric substrates are recommended for lower resistance in composite membranes.
- Commercial ion exchange membranes have significantly lower resistance (0.08–0.27 ohm.cm2).

## Abstract

In composite membranes, non-woven substrates are often included to offer higher mechanical strength. The use of non-wovens is currently limited in electrochemical applications, apart from lab-made electrospun non-woven membranes. In this manuscript, three commercial non-wovens are compared to test their potential use in acid-based electrochemical applications, for instance redox flow batteries, and are also compared to a woven fabric substrate. The three non-wovens are found to have variable suitability in terms of the stability of solvents used in further membrane processing. However, all are deemed limiting due to their relatively high area resistance (0.37–1.47 ohm.cm2). In comparison, free-standing and selective commercial ion exchange membranes have area resistances around 0.08–0.27 ohm.cm2. More open substrate backings such as a woven structure are recommended instead to allow for lower resistance of the resulting composites.