In this final thesis, we investigated the preformance of a low-temperature fuel cell with a proton exchange membrane. For this purpose, we used an experimental test system consisting of an electrolyzer, multimeters, a voltage source, two gas rezervoirs and a membrane-electrode assembly of a 9 cm2 fuel cell. Hydrogen was produced in an electrolytic cell and stored in a storage tank. We tested with two types of oxidants: a) with pure oxygen, also obtained from an electrolytic cell and b) with air from the atmosphere. The operating state of the fuel cell was determined by setting the ohmic resistance in the measuring system and the current and voltage produced by the fuel cell were measured. In this way, we determined the polarization curves and found that the fuel cell operates better when operating with oxygen than when operating with air. It produces the maximum power at lower loads, approximately in the area between 3.3O and 0.1O. It has the highest efficiency where the resistances in the vicinity are 3.3O.
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