Large–Scale, High-Performance, Durable and Low-Cost Membrane Electrode Assemblies for Proton Exchange Membrane Water Electrolyzers
Authors: Zeng Zhiqiao , Bliznakov Stoyan , Bonville Leonard J. , Ouimet Ryan J. , Niedzwiecki Allison , Capuano Christopher , Ayers Katherine E. , Maric Radenka 
Published: November 2022

Proton exchange membrane (PEM) water electrolyzers, designed to produce hydrogen from intermittent renewable energy, will play a key role in future sustainable energy systems.1 However, the widespread commercialization of PEM water electrolyzers is obstructed by their high cost, low durability, and safety concerns related to the hydrogen crossover. Currently, the production cost of green H2 is in the range of $3-8 kg-1. In order to boost the commercialization of this clean energy devices and lower the production cost of green H2, DOE implemented targets of $2 kg-1 by 2025 and $1 kg-1 hydrogen by 2030.2 In addition, the durability of all electrolyzer components has to be improved in order to increase the lifetime of a PEM water electrolyzer stack to the targeted 80,000 hours. These challenging targets inspired the researchers all over the world to work on development of novel catalyst and catalyst layers with decreased platinum group metal (PGM) loadings, invent new cost-effective methods for fabrication of membrane electrode assemblies (MEAs), develop innovative designs for the MEAs capable of decreasing the hydrogen crossover, and improve the corrosion resistance of the cell hardware and the other stack components to enhance their durability.

In this work, the unique Reactive Spray Deposition Technology (RSDT) is used to fabricate a high-performance, durable, and low-cost MEAs with geometric area of 680 cm2. These large scale MEAs have one order of magnitude lower PGM loadings in their catalyst layers in comparison to the state-of-the-art (SOA) commercial MEAs. The RSDT is a flame-based method that combines the catalysts synthesis and electrodes deposition in one step and thus substantially reduces the time and cost for MEAs fabrication.3–5 As fabricated large-scale MEAs with 680 cm2 geometric area of their electrodes, have loadings of 0.2 mgPt/cm2 in the cathode and 0.3 mgIr/cm2 in the anode, which are 10 times lower than the loadings in the SOA MEAs. The MEAs of interest have been tested at steady-state conditions that are typical for an industrial hydrogen production system for over 1000 hours. The cell voltage transients, as well as the periodically measured polarization curves during the test, clearly show that as fabricated MEAs have excellent activity and durability performance. Furthermore, the RSDT fabricated MEAs have integrated dual recombination layers that effectively reduce the hydrogen crossover to below 10 % LFL at all measured current densities (from 0.58 to 1.8 A/cm2). In addition, the MEA was subjected to comprehensive post-test analysis to study the degradation mechanisms governing the performance loss during the long-term durability test, and the results obtained will be presented and discussed in this presentation.

Reference

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2. https://www.energy.gov/eere/fuelcells/hydrogen-shot-summit-proceedings-panel-session-1-electrolysis

3. H. Yu, N. Danilovic, Y. Wang, W. Willis, A. Poozhikunnath, L. Bonville, C. Capuano, K. Ayers, and R. Maric, Appl. Catal. B Environ., 239, 133–146 (2018).

4. G. Mirshekari, R. Ouimet, Z. Zeng, H. Yu, S. Bliznakov, L. Bonville, A. Niedzwiecki, C. Capuano, K. Ayers, and R. Mari, Int. J. Hydrogen Energy, 46, 1526–1539 (2021).

5. H. Yu, L. Bonville, J. Jankovic, and R. Maric, Appl. Catal. B Environ., 260, 118194 (2020).