Work Update | Development of membranes and ionomer dispersions | Sep 2022

Partners CNR-ITAE, Hydrolite, and CNRS have been working on ionomer dispersions, nanofibre reinforcements, and reinforced membranes to supply material for the large area MEAs.

In preparation of the large area MEAs that will make up the ANIONE prototype stack, CNR-ITAE has developed and tested a composite membrane (SCAV). The membrane has a high conductivity and meets the project target (50 mS/cm). CNR-ITAE carried out a scale-up procedure for the membrane preparation to reach the dimension requested for the ANIONE prototype stack.

The membrane should possess both: low hydrogen cross-over values (>1% V) and it should be thin enough to meet the performance target. CNRS has developed different types of reinforcements using a range of thermostable polymers and different fibre functionalisation approaches and has associated these reinforcements with anion exchange ionomers to prepare reinforced membranes of target thickness. In order to learn the ANIONE membrane properties, Hydrolite has performed a systematic study of the ion exchange capacity and through-plane ion conductivity and compared this with a standalone membrane and commercial benchmark. CNRS has determined the in-plane hydroxide ion conductivity and the membrane mechanical properties, and measured the hydrogen crossover of the reinforced membranes. The results show that hydrogen crossover through the ANIONE reinforced membranes is 5 times lower than in the corresponding non-reinforced membrane.

The results are documented in D3.3.

Images of ANIONE project membranes. Left: SCAV scaled-up membrane. Right: SEM cross-section micrographs of reinforced ANIONE membrane.