Gas diffusion electrode

Besides these wetting characteristics, the gas diffusion electrode must, of course, offer an optimal electric conductivity, in order to enable an electron transport with low ohmic resistance.

The surface layer itself has such fine pores that, even when the pressure peaks, gas cannot flow through the electrode into the electrolyte.

This means that, in places with a high proportion of PTFE, no electrolyte can penetrate the pore system and vice versa.

Also, in the dispersion route (through evaporation of water and sintering of the PTFEs at 340 °C) the mechanical pressing is skipped and the produced electrodes are very porous.

For applications with liquid electrolytes, such as the zinc-air battery or the alkaline fuel cell, the dry mixture method is used.

It is not only used for research and development firms but for larger companies as well in the production of a membrane electrode assembly (MEA) that is in most cases used in a fuel cell or battery apparatus.

Companies that specialize in high volume production of GDE include Johnson Matthey, Gore and Gaskatel.

However, there are many companies which produce custom or low quantity GDE, allowing different shapes, catalysts and loadings to be evaluated as well, which include FuelCellStore, FuelCellsEtc, and many others.