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Geometries of flow fields have a strong impact on the gas distribution in fuel cells. In this work, two different flow field geometries are compared for high temperature polymer electrolyte fuel cells, a serpentine like flow field and a spiral one. Computational fluid dynamics analysis yielded a mixed flow distribution over the active area of the spiral flow field. This cell exhibited a significantly higher voltage than the cell with the serpentine flow field. Additionally, the degradation rate of the cell with the spiral flow field was five times lower after an operation of 1000 h. Moreover, electrochemical impedance spectroscopy and cyclic voltammetry presented lower resistances and 50% larger specific electrochemical surface area after long term tests for the cell with the spiral flow field compared to the one with the serpentine flow field.