It is well established that clamping pressure has an impact on the performance of polymer electrode membrane (PEM) fuel cells. Belleville springs & washers may be employed to maintain a given pressure. Solon Manufacturing Co. has designed an interactive tool to help select the optimal spring arrangement to incorporate into the PEM fuel cell design.

PEMs use hydrogen fuel and oxygen from the air to produce electricity. The Membrane Electrode Assembly (MEA) is an assembled stack of PEM, a catalytic layer, and a Gas Diffusion Layer (GDL). The MEA is between bipolar plates and gasket layers and these cells are stacked to produce a desired electrical output. The entire stack is commonly loaded with tie rods/studs to some optimal clamping pressure. The optimal pressure is based on several factors:
  1. Insufficient clamping force may result in leakage of the assembly.
  2. Reduced clamping force results in increased contact resistance between the GDL and the bipolar plates and this reduces cell performance.
  3. Excessive clamping force may reduce porosity of the GDL and reduce the flow of gas and liquid that can compromise cell performance.
  4. Excessive clamping force may mechanically damage components of the cell.
In addition, the elastomer seals that are used in the fuel cell stack tend to relax or degrade over time and exposure to temperature. This reduces the cell performance over time. Belleville springs can be assembled onto the tie rods to maintain optimal pressure on the fuel cell. The challenge is that there are many spring designs or stack arrangements that could be used for a given application. Solon’s PEM Fuel Cell Selection Tool can help engineer the most cost effective spring stack for each application.

Please complete the form below to access our online PEM Fuel Cell Clamping Force Calculator.