Membrane Insights for Better Fuel Cells

October 29, 2019

Resonant x-ray scattering (RXS) and x-ray absorption spectroscopy (XAS) with elemental sensitivity unravel structural features and chemical factors affecting morphology and ion transport in proton-conducting membranes.

Researchers at Lawrence Berkeley National Lab (Berkeley Lab) have shown how chemical and structural changes improve the performance of a novel ion-conducting polymer (ionomer) membrane from 3M Company. The team included Ahmet Kusoglu, a research scientist in Berkeley Lab's Energy Conversion Group

Using multiple x-ray characterization tools at the Advanced Light Source (ALS), the researchers took a closer look at the structural and chemical properties of new membrane materials at the nanometer scale. The membranes operate within fuel cells, which generate electricity from hydrogen fuel, and electrolyzers, which produce hydrogen fuel by splitting water. By preventing contact between positive and negative electrodes, these membranes help avoid catastrophic failure while allowing selective passage of ions to complete the circuit.

Because device efficiency can be improved through higher-temperature operation, researchers are interested in membranes that work in hotter, drier environments. One of 3M’s new class of ionomers, performs well at both higher and lower relative humidity. To better understand why, a collaboration between researchers from 3M, Berkeley Lab’s Energy Storage and Distributed Resources Division, and the ALS took a multimodal approach to exploring the interplay between chemistry, structure, and function in these new materials.

The work provides insight into the factors affecting the proton conductivity of ionomers used for fuel cells and the production of hydrogen fuel. Read more about the research here: als.lbl.gov/multimodal-study-of-ion-conducting-membranes/