multifunctional materials; pore-scale model; modeling and simulation; microstructure analysis; proton exchange membrane fuel cells (PEM, PEFC); tomography; multiphysics model
Dujc Jaka, Forner-Cuenca Antoni, Marmet Philip, Cochet Magali, Vetter Roman, et al. (2018), Modeling the Effects of Using Gas Diffusion Layers With Patterned Wettability for Advanced Water Management in Proton Exchange Membrane Fuel Cells, in Journal of Electrochemical Energy Conversion and Storage
, 15(2), 021001.
Holzer Lorenz, Pecho Omar, Schumacher Jürgen, Marmet Philip, Büchi Felix, et al. (2017), Microstructure-property relationships in a gas diffusion layer (GDL) for Polymer Electrolyte Fuel Cells, Part II: pressure-induced water injection and liquid permeability, in Electrochimica Acta
, 241, 414-432.
Holzer Lorenz, Pecho Omar, Schumacher Jürgen, Marmet Philip, Stenzel Ole, Büchi Felix, et al. (2017), Microstructure-property relationships in a gas diffusion layer (GDL) for Polymer Electrolyte Fuel Cells, Part I: effect of compression and anisotropy of dry GDL, in Electrochimica Acta
, 227, 419-434.
Stenzel Ole, Pecho Omar, Holzer Lorenz, Neumann Matthias, Schmidt Volker (2016), Predicting effective conductivities based on geometric microstructure characteristics, in AIChE Journal
, 62(5), 1834-1843.
Capone Luigino, Marmet Philip, Holzer Lorenz, Dujc Jaka, Schumacher Jürgen, Lamibrac Adrien, Büchi Felix, Becker Jürgen, An ensemble Monte Carlo simulation study of water distribution in porous gas diffusion layers for proton exchange membrane fuel cells, in Journal of Electrochemical Energy Conversion and Storage
This project is part of the joint project "Reduction and reuse of CO2: renewable fuels for efficient electricity production" that combines innovative technologies for I) hydrogen production from renewable resources (PEC water splitting), II) low temperature methanation of CO2 (catalysis) with renewable hydrogen, and III) electricity supply from renewable energy carriers by conversion with high efficiency technologies (fuel cells). This project addresses fuel cells operating on pure hydrogen that produce zero emissions at the source. Electric vehicles containing proton exchange membrane fuel cells (PEFC) have the potential to replace conventional combustion based vehicles. Thereby, fuel cell technology can contribute substantially to the reduction of the CO2 emissions in the mobility sector. Other applications are expected for combined heat and power (CHP) units, and backup power units.The research topic of the project is to design multifunctional materials for polymer electrolyte fuel cells (PEFC) with customised local transport properties (particularly for the transport of liquid water). These new multifunctional, high performance, low cost materials will increase cell performance and robustness through optimised water management, reduced complexity of the balance of plant (BoP) by operating on dryer reactant gases, improve durability by more homogeneous humidification in the plane of the cell and thus, considerably reduce the cost of PEFC per unit of energy produced. This is important for the market introduction of PEFCs.The following results are expected from the project:• Virtual material models and material parameterisations that are important for material producers. • Different software packages for pore-scale simulations of liquid water in porous materials and for large-area PEFC simulations.• Follow-up industry projects on material design with PEFC component suppliers, and transfer of the project results to Swiss SMEs that can take part in the value chain of PEFCs. The work is split in four work packages. In WP1 virtual material models of the dry gas diffusion layer (GDL) and the microporous layer (MPL) of PEFCs are constructed by use of tomographic image data (X-ray, FIB-SEM and BIB-SEM). The transport properties (gas diffusion, charge, heat) of the materials are extracted from the tomograms. Liquid water transport in the porous layers is investigated in WP2: a pore-scale model is implemented, where the 3D fiber / pore-structure is accounted for. From the pore-scale model we obtain the 3D-distribution of the water filled and open (gaseous) pore domains. A topological analysis of the filled and open domains obtained by the simulation results are compared to the 3D-data (from X-ray tomography of wet samples). Topological information of the domains includes tortuosity, constrictivity, connectivity, volume fraction, surface area etc. Surface properties play a decisive role in the behaviour of the porous materials for the uptake, transport and release of water. Therefore the interaction of liquid water with the surface (i.e. release of droplets) and the properties of the materials (effective and apparent contact angle) need to be better understood, which is the focus of WP3. In WP4, a multi-scale model is developed that links the pore-scale model of the GDL/MPL to a macrohomogeneous multiphysics model of a PEFC. New multifunctional material designs are proposed on the basis of this model.