Using processes derived from paper technology, organic fibers, fillers, and additives can be mixed with metal powder to produce a flat product. In a subsequent heat treatment, the organic components are removed, leaving a purely porous metallic material, the so-called sinter paper. This approach is used for the development of an innovative Gas Diffusion Layer (GDL) for mobile fuel cells. GDLs are arranged between the bipolar plate and the electrode in fuel cell stacks. They ensure optimal gas distribution as well as the removal of water, heat, and electricity. Metallic sinter paper that meets the materials specification of stainless steel 316L could be made. The thickness of the paper was reduced to 200 µm, and the porosity of the base material reaches values around 60 %. Morphological characterization was carried out based on high-resolution µCT scans and their analysis via the software package GeoDict.