What is it about?
Standard fuel cell testing provides an "average" reading of performance, but this can be misleading. In reality, a Polymer Electrolyte Membrane Fuel Cell (PEMFC) is a landscape of extremes: the "inlet" where hydrogen enters might be dry and cool, while the "outlet" is hot and flooded with water. These inhomogeneities—differences in conditions across the active area—are the primary drivers of material degradation and premature failure.This research details the development and application of a custom diagnostic hardware system. The key features include:16-Segment Isolation: A $49\text{ cm}^2$ active area split into sixteen fully isolated segments, allowing researchers to measure current and voltage locally. Individual Segment Control: The ability to manipulate each zone independently to simulate localized faults. Integrated Reference Electrodes: Providing the ability to separate the losses of the anode from the cathode at every single point on the map. The team applied this tool to track the Effective Platinum Surface Area (EPSA). By running an Accelerated Stress Test (AST) consisting of 100,000 cycles, they could visualize how the platinum catalyst disappears unevenly across the cell's surface, rather than decaying at a uniform rate.
Featured Image
Photo by Wesley Tingey on Unsplash
Why is it important?
If a fuel cell fails because one small corner gets too hot or too wet, the entire system stops working. Traditional "single-output" testing cannot tell you which corner failed or why. This work is a cornerstone for the industry because: Revealing "Hidden" Stress: It identifies "hot spots" where degradation is accelerated, allowing engineers to redesign flow channels to distribute heat and water more evenly. Long-Term Durability: By testing up to 100,000 cycles, the study provides a rare look at the ultra-long-term survival of platinum catalysts under realistic, uneven operating conditions. Advanced Diagnostics: The combination of segmentation and reference electrodes allows for a "3D" diagnostic view—mapping performance both across the surface (horizontal) and through the layers of the cell (vertical).
Perspectives
This study moves PEMFC research away from "black-box" bulk measurements and into the era of precision diagnostics. The 16-segment hardware essentially functions as a microscope for electrochemical activity. In the past, researchers might observe that a cell lost 20% of its power, but they wouldn't know if the loss was a 20% decline everywhere or a 100% failure in one-fifth of the cell. The findings regarding EPSA degradation are particularly revealing. They suggest that the "death" of a fuel cell is a localized event that spreads. By understanding the spatial patterns of platinum loss, we can move toward "active management" of fuel cells. Future systems might use this data to adjust gas flow in real-time, redirecting hydrogen away from degrading segments to prolong the overall life of the stack.
Dr. Shankar Raman Dhanushkodi
University of British Columbia
Read the Original
This page is a summary of: Polymer Electrolyte Membrane Fuel Cells: Characterization and Diagnostics, ECS Transactions, August 2014, The Electrochemical Society,
DOI: 10.1149/06403.0547ecst.
You can read the full text:
Contributors
The following have contributed to this page
