Advances in Reinforced Polymer Electrolyte Membrane Designs for Improved Direct Coated Electrodes

Abstract

In recent years, hydrogen fuel cells have become a key clean technology for the decarbonization of the transport sector. Significant investments are directed towards scaling the hydrogen infrastructure and the production of fuel cell vehicles to meet cost and climate targets set by governments across the globe. To achieve the required scale at cost, manufacturers of fuel cell components such as membrane electrode assembly (MEA) need to adopt high throughput processes while maintaining quality and performance of MEAs to meet heavy duty vehicle requirements.Roll to roll direct coating (DC) process using slot die coating technique is proposed to deliver the lowest cost/highest throughput method for production of MEAs. Electrode ink containing catalyst, ionomer and solvents are applied directly on the membrane before drying to remove the solvents from the coating. The direct contact of solvents with PEM ionomer can create challenges resulting from ionomer swelling and shrinking to produce poor electrode quality and MEA performance.This talk will discuss different design approaches to produce direct coated MEAs and present a novel approach in membrane design to address DC challenges to meet performance and quality targets that would enable the use of DC for scaling the fuel cell production.Applying Gore’s knowledge in expanded poly-tetra-flour-ethylene (ePTFE) reinforcement properties and fuel cells research we developed a membrane that would reinforce the polymer electrolyte and electrode layers simultaneously while minimizing the impact of solvents used in DC processes. This results in improved MEA quality and performance compared to a traditional reinforced membrane design and enables the use of DC for high throughput/low-cost MEA manufacturing. Figure 1