Leveraging Digital Advanced Manufacturing to Enable Polymer Electrolyte Fuel Cells With Ultrahigh Gravimetric Power Density

The integration of hydrogen fuel cells into aerospace and mobility applications is limited by the weight and volume of fuel cell system, where bipolar plates alone account for up to 80% of the fuel cell stack mass and 60% of its volume. This study addresses this challenge by developing a new class of lightweight and compact porous distributors engineered through computational modeling that enable ultrahigh power densities. The research begins with a graphene-coated nickel foam porous distributor, which enhances reactants transport and interfacial conductivity, achieving a peak power density of 1.52 W/cm², representing a ~50% improvement over conventional designs. To further boost gravimetric power density, titanium was adopted as a base material, and porous architectures were optimized using CFD-driven design and flow control. Two advanced manufacturing techniques - laser powder bed fusion (LPBF) and laser micromachining - were employed to fabricate titanium-based porous distributors with tailored geometry. While the optimised LPBF lattice structure reached 1.18 W/cm², the laser-patterned non-homogeneous titanium architecture demonstrated a breakthrough performance of 1.71 W/cm², translating to volumetric and gravimetric power densities of 12 kW/L and 9 kW/kg, respectively. These values surpass current commercial benchmarks and even exceed EU 2030 targets. This work demonstrates how integrating digital design, flow control, and advanced materials/manufacturing enables a transformative leap in fuel cell power density, with implications extending to electrolysers, heat exchangers, and batteries.