Before answering the question about the most common thickness, it’s important to understand the application of the Gas Diffusion Layers (GDLs) in question. The two most common applications of Gas Diffusion Layers (GDLs) are fuel cells and electrolyzers, and each of these will have different thicknesses of GDLs.
The applications of fuel cells and electrolyzers are complementary to each other; while fuel cells use hydrogen and oxygen to generate electricity, electrolyzers use electricity to generate hydrogen and oxygen by splitting water molecules. GDLs play a crucial role in both these processes by providing a stable and uniform distribution of gases and liquids to the active sites of the electrodes, thereby enhancing the electrochemical reactions and increasing the efficiency of the overall system.
There is a wide range of possible materials that can be used for Gas Diffusion Layers, and the thickness of GDLs will also depend on the type of materials that are used. Commercial grades of GDLs available from CAPLINQ vary depending on the type of material used:
- LINQSTAT Electrically Conductive Plastic : 70 — 100 micron
- LINQCELL Carbon Cloths & Activated Carbon Fabrics: 350 — 400 micron
- LINQCELL Graphitized Carbon Paper and Panels: 180 — 2900 micron
- LINQALLOY Sintered Titanium: 25 — 3000 micron (any size available)
It is important to note that the thicknesses listed are simply those requested by our customers. CAPLINQ can often custom-make specific thicknesses to meet specific applications, so be sure to contact us to ask for your specific thickness.
Most common thicknesses for GDLs used in Fuel Cells
The thickness of Gas Diffusion Layers (GDLs) in fuel cells is typically measured in microns, with the typical range being between 75 — 400 micrometers. Factors such as the type of material used for the GDL, the operating conditions of the fuel cell, and the desired performance characteristics of the fuel cell can all affect the thickness of the GDL.
Furthermore, treatments such as additional Microporous Layers and PTFE (Teflon) can also affect GDL thickness.
Our four most popular graphitized carbon paper products (ranked in order of popularity) are as follows:
- LINQCELL GDP 180: 180-micron thick
- LINQCELL GDP 210: 210-micron thick
- LINQCELL GDP 340: 340-micron thick
- LINQCELL GDP 240: 240-micron thick
Most common thicknesses for GDLs used in Electrolyzers
Generally speaking, GDLs used in electrolyzers are thicker than those used in fuel cells. Because in electrolyzers, GDLs are used in the electrode of the anode, where water is split into hydrogen and oxygen, this process requires a larger surface area for the electrode to provide more active sites for the electrochemical reactions to take place. This can be achieved by using GDLs with a greater thickness. Furthermore, thicker GDLs offer more compressibility which allows the electrolyzers to be more efficient.
Where the thickness of GDLs in fuel cells is typically measured in microns, the thickness of GDL’s for electrolyzers is more commonly measured in millimeters. The typical thickness of GDL’s for electrolyzers is in the range of 1.5 — 2.9 millimeters. Electrolyzers also do not normally have additional PTFE layers.
CAPLINQ’s four most popular graphitized carbon paper products (ranked in order of popularity) are as follows:
- LINQCELL GDL 1500: 1.5 millimeters thick
- LINQCELL GDL 1850: 1.85 millimeters thick
- LINQCELL GDL 2900: 2.9 millimeters thick
- LINQCELL GDL 2200: 2.2 millimeters thick
To be clear, it is the customers who have dictated these thicknesses, as we can custom make most any thickness of Carbon Paper or Panel.
CAPLINQ is a proud innovator in the space of graphitized carbon paper and panels and we love to work with customers to address their specific manufacturing challenges. We proudly offer our products to manufacturers of electrolyzers and fuel cells large and small.
Please visit our website and feel free to contact us if you have any questions about any of the products we offer.