Copper-based reforming catalyst was placed adjacent to ADVENT Technologies high-Temperature polymer electrolyte membrane/electrode assembly in a novel internal reforming methanol fuel cell (IRMFC) and tested for their electrochemical properties and chemical stability under various methanol/water anode feedstreams. Polarization measurements and AC impedance spectroscopy combined with measurements of reactor outlet composition were carried out. Methanol is being reformed inside the anode compartment of the fuel cell at 200 A degrees C producing H-2, which is readily oxidized at the anode to produce electricity. The reformer provides enough hydrogen supply for efficient fuel cell operation at 600 mV with 0.2 A cm(-2) and a hydrogen stoichiometric ratio of 1.2 (lambda(H2) = H-2 fed/H-2 reacted = 1.2). However, unreacted MeOH ( 5 %) in combination with low H-2 content poisons the anode electrode and the cell performance rapidly decreases. Gradual recovery of the initial performance under pure H-2 is observed after switching to pure H-2. A slight improvement of the cell's design by the introduction of a pre-reforming step significantly improves the electrocatalytic behavior.