Engineering topics

Pfeilsticker, Jason

Publications and source records attributed to Pfeilsticker, Jason.

5 records

DOE OSTI2023

Crack detection in fuel cell electrodes using a spatial filtering technique for overcoming noisy backgrounds

Image processing is a powerful tool that allows for rapid and automated data parsing in settings that occupy large variable spaces and require large data sets. Feature detection on difficultly discerned backgrounds is a subset of image processing that facilitates the extraction of quantitative metrics from otherwise subjective data. Crack detection and quantification is an important capability in polymer electrolyte membrane fuel cell quality control, failure analysis, and optimization. This work presents a technique to perform crack detection and quantification which overcomes challenges faced by commonly used image segmentation techniques. We demonstrate the use of a geometrically filtered noise‐level detection technique to select a binary threshold value from which we then quantify how cracked a sample is. Furthermore, we demonstrate the accuracy of our technique using programmatically generated test images of known crack amounts and their performance on real‐world fuel cell catalyst layer samples.

30 DIRECT ENERGY CONVERSION↗

DOE OSTI2021

Exploring the Interface of Skin-Layered Titanium Fibers for Electrochemical Water Splitting

Water electrolysis is the key to a decarbonized energy system, as it enables the conversion and storage of renewably generated intermittent electricity in the form of hydrogen. However, reliability challenges arising from titanium-based porous transport layers (PTLs) have hitherto restricted the deployment of next-generation water-splitting devices. Here, it is shown for the first time how PTLs can be adapted so that their interface remains well protected and resistant to corrosion across ˜4000 h under real electrolysis conditions. It is also demonstrated that the malfunctioning of unprotected PTLs is a result triggered by additional fatal degradation mechanisms over the anodic catalyst layer beyond the impacts expected from iridium oxide stability. Now, superior durability and efficiency in water electrolyzers can be achieved over extended periods of operation with less-expensive PTLs with proper protection, which can be explained by the detailed reconstruction of the interface between the different elements, materials, layers, and components presented in this work.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2020

An Experimental Investigation of Multilayer Flow in a Slide Die Coating Process

Roll-to-roll coating technology has been actively applied not only for conventional film production but also for emerging energy devices such as organic solar cells, organic light emitting diodes, batteries, smart windows, and fuel cells. The devices are multilayer structures requiring several coating and drying steps when implemented in a serial fashion, which increases capital costs and energy consumption. Simultaneous multilayer (ML) coating technologies present an opportunity for cost reductions and improved process efficiency by reducing equipment footprint and the number of process steps. In this talk, we experimentally investigate ML slide die coating flow for the manufacturing of fuel cell membrane electrode assemblies (MEAs). For ML slide coating, understanding fluid properties such as density, surface tension, and viscosity are necessary for stable flows and limiting intermixing of the miscible layers. Here, we utilize a design-of-experiment methodology - Box-Behnken design (BBD) - to correlate ink formulation parameters to fluid properties. Using the ink properties obtained from the BBD, we performed numerical flow simulations to obtain a proper process conditions to guide experimental coating trials. Finally, experimental verification is performed on a ML slide die and a degree of miscibility was observed for various ink formulation conditions.

28 EE - Advanced Manufacturing Office (EE-5A)↗

DOE OSTI2020

Caltalyst Layer Crack Detector, or CLCD ("clicked") [SWR-20-60]

The Caltalyst Layer Crack Detector, or CLCD ("clicked") is a program that takes in optical micrographs of catalyst coatings for PEM fuel cells or electrolyzers and calculates the percent area that consist of cracks. It does so using a custom algorithm that searches for dark features larger than the background graininess of the catalyst layer.

Pfeilsticker, Jason↗

DOE OSTI2020

Elucidating the Role of Ionomer in the Performance of Platinum Group Metal-free Catalyst Layer via in situ Electrochemical Diagnostics

The ionomer content in platinum group metal (PGM)-free polymer electrolyte fuel cell (PEFC) cathode catalyst layer (CCL) plays an important role in the electrode gas transport properties, proton conductivity, and hence, membrane electrode assembly (MEA) performance. In this work, the ionomer content in the CCL is varied, influencing electrode microstructure by altering porosity, tortuosity, as well as ionomer distribution and coverage of the catalyst particles. A novel technique consisting of a H 2 pump, combined with a Pt black sensor layer, is used to measure the bulk mass transport resistance of a series of PGM-free CCL prepared with different ionomer contents. The values for bulk electrode mass transport resistance are contrasted with electrode proton transport resistance in the cathode catalyst layer, establishing a clearly defined trade-off between two key performance limiting phenomena and identifying a need for novel PGM-free electrode fabrication strategies.

25 ENERGY STORAGE↗