To meet the increasing energy demand and diversify energy resources, fuel cells emerge as a promising solution. This Ph.D work aims to contribute to the development of Proton Exchange Membrane Fuel Cells (PEMFCs), with a specific focus on bipolar plates (BPs) which ensure gas distribution and current collection. The first objectives are to design and manufacture stainless steel BPs using 3D printing (SLM - Selective Laser Melting) and to develop organic and inorganic anticorrosion coatings. Multiple channel architectures will be designed and characterized, including in-situ assessments with membrane-electrode assemblies (MEAs). Coatings will also be characterized, particularly in terms of their corrosion resistance through polarization methods. In the second phase, the aim is to integrate the optimized BPs with MEAs and thoroughly study the performance of PEMFCs using electrochemical techniques to gain fundamental insights into the mechanisms that limit PEMFCs performance.