The straightforward synthesis and application of conductive and corrosion‐protective composite coatings suitable for the preparation of bipolar plates of proton exchange membrane fuel cells (PEMFCs) are achieved by a scalable and solvent‐free atmospheric plasma deposition process. Small three‐dimensional (3D) carbon black nanoparticles and large two‐dimensional (2D) natural graphite flakes are investigated independently and together as conductive fillers. It is demonstrated that the dual‐sized conductive fillers strategy traditionally used for the preparation of composite bipolar plates is not transposable for the proposed atmospheric plasma deposition process. Only the composite coatings prepared from large 2D natural graphite flakes enable a significant decrease of the corrosion current in simulated proton exchange membrane fuel cell conditions while ensuring interfacial contact resistance in the order of several tens of mΩ·cm2.