Ice Formation in Gas-Diffusion Layers

Dursch, Thomas; Radke, Clayton J.; Weber, Adam Z.

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DOE OSTI · 1082174

Ice Formation in Gas-Diffusion Layers

Dursch, Thomas·Radke, Clayton J.·Weber, Adam Z.

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Abstract

Under sub-freezing conditions, ice forms in the gas-diffusion layer (GDL) of a proton exchange membrane fuel cell (PEMFC) drastically reducing cell performance. Although a number of strategies exist to prevent ice formation, there is little fundamental understanding of the mechanisms of freezing within PEMFC components. Differential scanning calorimetry (DSC) is used to elucidate the effects of hydrophobicity (Teflon® loading) and water saturation on the rate of ice formation within three commercial GDLs. We find that as the Teflon® loading increases, the crystallization temperature decreases due to a change in internal ice/substrate contact angle, as well as the attainable level of water saturation. Classical nucleation theory predicts the correct trend in freezing temperature with Teflon® loading.

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30 DIRECT ENERGY CONVERSION Freeze, gas diffusion layers, fuel cells, crytallization

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Dursch, Thomas, Radke, Clayton J., Weber, Adam Z.. 2010-07-10. Ice Formation in Gas-Diffusion Layers. https://www.osti.gov/biblio/1082174

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