Hydrogen, one of the planet's most abundant elements, is gaining recognition in the transportation industry as a crucial fuel source for fuel cells. These fuel cells play a significant role in converting the chemical energy of a fuel into usable electricity and heat without combustion.
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Due to their efficiency, quick refueling, and longevity, they have recently made headway in the electric vehicle market. Major truck manufacturers are exploring fuel cells as a viable solution for long-haul goods transportation and reducing harmful emissions.
How Do Hydrogen Fuel Cells Work?
A fuel cell consists of three main components: an anode, a cathode, and an electrolyte membrane.
The fuel cell receives hydrogen at the negatively charged anode, while oxygen is supplied to the positively charged cathode.
Within the fuel cell, protons pass through the porous electrolyte membrane, while electrons travel externally from the anode to the cathode, generating an electric current and excess heat.
The protons, electrons, and oxygen combine at the cathode to produce water molecules. Since fuel cells have no moving parts, they operate silently and exhibit exceptional reliability.
Fuel cell manufacturers employ innovative manufacturing techniques to consistently produce high-quality bipolar plates and membranes that meet stringent specifications.
The quality characteristics of bipolar plates, such as channel straightness, shape, and texture, are critical as they can impact the flow of oxygen or hydrogen, affecting the overall efficiency of the electrochemical process.
Any design deviations can disrupt the materials' flow rate, leading to pressure changes and gradually diminishing energy output.
Characterizing Fuel Cell Surfaces
Surface properties are crucial in fuel cell efficiency and must be maintained within specific target parameters. To overcome these challenges, manufacturers rely on non-contact optical metrology inspection methods.
Previously, manufacturers used coordinate measuring systems (CMMs) to assess plate flatness and channel depth. However, this approach provided limited points, resulting in time-consuming examinations.
Manufacturers utilizing 3D non-contact optical profilers can rapidly and consistently inspect bipolar plate channels, capturing millions of data points and providing high lateral resolution across the entire surface.
One effective solution is the Zygo 0.5x ZWF objective, which offers a large field of view of >30 mm. By employing area stitching techniques to assess the entire plate, it becomes possible to accurately determine channel depth, channel straightness, and overall sealing flatness.
Precisely determining channel depth enables fuel cell plate designers to minimize plate thickness, optimizing the entire fuel cell stack and reducing overall mass. As fuel cells become increasingly prominent in electric vehicles, strict manufacturing specifications must be met to ensure their successful production.
Compared to CMM inspections, optical surface topography measuring instruments, such as Zygo's 3D non-contact optical profilers, provide more comprehensive, faster, and cost-efficient in-process surface texture and form measurements.
As automotive engineers and designers continue to push the boundaries of efficient and clean energy systems, Zygo remains committed to partnering with manufacturers, offering precise surface measurements and valuable insights.
This information has been sourced, reviewed and adapted from materials provided by Zygo Corporation.
For more information on this source, please visit Zygo Corporation.