Porous Transport Layer Based On Multiple Micro And Nano Sintered Porous Layers

A multilayer porous transport layer (PTL) for electrochemical cells, positioned between a bipolar plate and a catalyst layer, comprises at least two sintered porous layers of a conductive material (e.g., titanium or stainless steel). The PTL features a graded structure where the mean particle size decreases from the second porous layer (oriented toward the bipolar plate) to the first porous layer (oriented toward the catalyst layer). The layers consist of irregularly shaped particles defined by an irregularity parameter $\text{IP} = D/d < 5$ and a roundness $\text{RN} = P^2/4\pi A > 1.2$, where $D$ is the smallest surrounding circle diameter, $d$ is the largest internal circle diameter, $P$ is the perimeter, and $A$ is the area of the 2D projection.