MAINSTREAM ENGINEERING CORP SBIR Phase I Award, July 2023

Carbon emissions have led to global warming and must be curbed to slow the rapidly increasing temperatures that will lead to catastrophic drought, food shortages, and scarcity. The U.S. government is targeting carbon pollution-free electricity by 2035 and an economy-wide net-zero emissions goal no later than 2050. This ambitious goal requires scaling affordable hydrogen production (<$1/kg), transport, storage, and use across all areas of the economy. While areas have been tackled, the generation of clean hydrogen at feasible costs is still challenging, with the majority being produced by grey hydrogen, or steam-methane reformation that still consumes fossil fuels and produces natural gas. This hydrogen is not only used for power generation but is critical in the production of sustainable fertilizers and numerous chemicals that modern life depends on. While much work has gone into the development of water electrolyzers for hydrogen production from water, they are primarily proton exchange membrane (PEM) based systems, which while effective and have a simple balance of plant, require expensive membranes, precious metal catalysts and corrosion resistant cell components. There is therefore a need for an alternative with lower cost membranes, catalysts, and cell components. Alkaline membrane water electrolysis represent a promising alternative to enable this. The existing commercially available membranes do, however, suffer from long term chemical and thermal stability at relevant oxidation potentials. There is therefore a need for new low cost, improved membranes and membrane electrode assemblies (MEA) for alkaline membrane water electrolysis. Mainstream Engineering will develop an alkaline exchange membranes (AEM) and MEA that can utilize pure water fed into the system. Improvements in the polymer will enable this transformational technology to grow in market share through ease of operation and reduced costs. These modifications will enable an AEM that can operate with dilute potassium hydroxide up to 80 °C, with performance of >1 A/cm2 at 1.75 V, and a degradation rate of < 4 mV/1000 hours, enabling hydrogen production at lower total cost of ownership than existing PEM systems, which will help spur the adoption of green hydrogen production to enable a clean, carbon emission-free future. Low-cost energy efficient production of hydrogen has many benefits for green energy and industrial hydrogen production. An efficient low-cost alkaline water electrolyzer will lower the cost of hydrogen for fuel cell vehicles, industrial hydrogen and in combination with a hydrogen fuel cell can be used for capture and storage of excess renewable energy.