Preliminary results for a new methodology of measuring porosity in gas diffusion electrodes are presented. A rapid, non-destructive method to characterize composite materials processed in a film or belt form having pores as an integral component is under development. The methodology described specifically here would serve a need in the fuel cell industry, but is also generally applicable to quality control in the production of any porous media. The approach utilizes thermal effusivity (TE) measurements and is directed at quality control in the mass production of fuel cell and battery electrodes. In order to magnify the impact that pores have on the aggregate TE signature, difference measurements were performed. TE difference values were obtained, taking data for the porous media in two different gaseous environments: air and helium. The significant differences in the thermal properties due only to changing the flooding gas leads to a difference signal that correlates to porosity.
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