Unlocking the Full Potential of Electrolysis with Next-Generation Proton Exchange Membrane Stacks (UNICORN)

A major outcome of the UNICORN project will be a step-wise change in the development of proton exchange membrane water electrolyser (PEMWE) stacks with the potential to disrupt the current electrolyser landscape that relies exclusively on perfluorinated membranes, platinum-coated titanium bipolar plates, and high loadings of iridium catalyst. These materials result in large capital expenditure costs and, ultimately, an expensive cost of green hydrogen. The unique operating design of HYSTAR's PEMWE stacks coupled with the reduced cost and increased sustainability aspects of hydrocarbon membranes, coated stainless steel bipolar plates, and reduced iridium loadings will provide increased rates of hydrogen production at a significantly reduced cost. These innovations will contribute directly to the increased adoption of green hydrogen technologies, helping Europe reach its emissions reduction targets and strengthen European excellence in the area of green hydrogen. The demonstration of a 40 kW PEMWE stack with beyond state-of-the-art components capable of delivering an unprecedented levelized cost of green hydrogen represents a tremendous step in accelerating the green transition. Providing low-cost green hydrogen is necessary to decarbonize industrial manufacturing sectors that rely on hydrogen as a chemical feedstock, e.g., steel and cement, as well as the heavy-duty transport sector, e.g., long-haul trucking and maritime transport.

PEMWE is currently the most promising route towards green hydrogen production due to the "zero-gap" cell configuration, leading to higher operational current densities, and nearly instantaneous response to fluctuating power output, making it ideal for coupling with renewable energy sources. The major shortcoming of PEMWE, however, is that it requires the use of expensive components, made from critical raw materials (CRM), to overcome the harsh acidic operating environment, highly oxidative potentials at the anode, and stringent gas-crossover requirements. Today's commercial PEMWE systems all rely on noble metal catalysts and protective coatings, titanium-based bipolar plates, and perfluorinated sulfonic acid (PFSA)-based membranes. These materials lead to increased capital expenditure (CAPEX) costs and have been identified as either CRM (e.g., platinum group metals and titanium) or materials with sustainability/environmental concerns (e.g., PFSAs). Developing low cost, non-toxic, safe-by-design PEMWE stacks is therefore crucial to ensure the future of electrolysis remains affordable, circular, and sustainable. The UNICORN project seeks to combine innovative components, e.g., coated stainless steel BPPs and hydrocarbon membranes, with the unique electrolyser design from HYSTAR that allows for reduced iridium loadings and high current density operation to demonstrate a commercial-scale 40 kW PEMWE stack with increased performance, decreased capital expenditure, and improved sustainability aspects compared with current commercial standards. The integration of beyond state-of-the-art electrolyser components described above with Hystar's unique electrolyser configuration will elevate the proposed UNICORN electrolyser technology from TRL 4, all material technologies already validated at the lab-scale, to TRL 6, material technologies demonstrated in a PEMWE stack under relevant environment.