Online Optic Enabled X-Ray Analyzer for Fuel Cell Manufacturing

This Small Business Innovation Research (SBIR) Phase I project seeks to demonstrate the feasibility of developing an online X-ray analyzer for real-time measurement of catalyst coating thickness of gas diffusion electrode (GDE). The electrodes in the fuel cell, either the single-element GDE, or an anode and cathode in a complete a membrane electrode assembly (MEA), is the critical electrochemical component for every proton exchange membrane (PEM) fuel cell. The catalyst coating of GDE is one of the more expensive manufacturing processes in the MEA production. However, the process is lacking an online technology for catalyst thickness and distribution measurements. As a result, the impact of manufacturing changes as they relate to both production and performance is not fully understood. The unique, optic-based XRF analyzer proposed in the current project will allow real-time measurement of the catalyst-coating thickness and elemental distribution. It will provide timely feedback for the GDE production process where changes or improvements can be accommodated immediately. This would improve yield and the overall performance of the GDE products. The objective of the project is to demonstrate the feasibility, while the ultimate goal is to build an instrument that will be used on a GDE production line. The broader impact/commercial potential of this project is the technique developed would benefit both the manufacturing process as well as the overall performance of the fuel cell system. Fuel cell stack efficiency can drop significantly after a few thousand hours of use, which is part of the reason the fuel cell system is not widely used for stationary distributed energy generation. Thus, there is an immediate need to reduce the degradation rate and extend the stack operating life. The measurement of catalyst coating thickness and distribution in production can be a critical link to understand the performance impacts of subtle production changes. Currently there is no practical online, real-time, continuous, nondestructive method to provide this information. The X-ray analyzer incorporates the latest X-ray optics and makes it possible to achieve the anticipated performance with a low power and compact system. The dual benefit of using manufacturing process control to decrease cost and improve final product performance is attractive, enabling a more competitive industry in the U.S. that is more efficient and has a smaller environmental footprint than before. Further, the measurement techniques developed for the fuel cell process can readily be applied to other similar rolling or coating manufacturing processes.