Pore-Scale Modeling of Mass Transport in Partially Saturated Cathode Gas Diffusion Layers of Proton Exchange Membrane Fuel Cell

Abstract

Proton exchange membrane fuel cells (PEMFCs) have the advantages of high specific power, good stability, and zero emissions, making them clean and efficient energy conversion devices. Water management is one of the technical challenges limiting the development of PEMFC, with liquid water blocking the pores and increasing the resistance to mass transport. In this paper, a two-dimensional (2D) multiphase lattice Boltzmann (LB) model is developed to obtain the liquid water morphology within the gas diffusion layer (GDL). A 2D multicomponent flow Lattice Boltzmann model considering electrochemical reactions is established to investigate the effects of water saturation, activation overpotential, and pressure difference between the inlet and outlet gas channels on mass transport. At high water saturation, the liquid water forms water films within the GDL preventing reactive gas transport and water vapor are blocked near the catalyst layer making it difficult to remove. The PEMFC can achieve higher current densities at high activation overpotentials, but oxygen starvation will be exacerbated. Increasing the pressure difference between the inlet and outlet gas passages effectively increases the oxygen concentration and reduces the water vapor concentration in the GDL. The present study improves the understanding of the effect of GDL microstructure on mass transport and performance of PEMFC from the mesoscopic scale.

Review on Chitosan and Two-Dimensional MoS2-Based Proton Exchange Membrane for Fuel Cell Application: Advances and Perspectives

“…5,6 The PEM is the essential part of the fuel cell, allowing passage for proton conduction and blocking the flow of electrons and fuel. 5,6 High methanol crossover and decreased proton conduction ability at high emperature limit the use of Nafion membranes. 3 Therefore, developing a new low-cost polymer electrolyte membrane (PEM) with desired characteristics is becoming an imperative goal for the research community.…”

“…Protons diffuse through the polymeric membrane to the cathode, where the oxidizing agent, oxygen, accepts them and combines with reduced oxide anion and oxidized protons to produce water, the final effluent. The polytetrafluoroethylene (PTFE) backbone-based membranes used in PEMFC systems typically have a limited number of perfluoroether side chains that end in sulfonic acid groups and are thus very acidic by nature. , …”

“…number of perfluoroether side chains that end in sulfonic acid groups and are thus very acidic by nature. 5,6 The PEM is the essential part of the fuel cell, allowing passage for proton conduction and blocking the flow of electrons and fuel. 5,6 High methanol crossover and decreased proton conduction ability at high emperature limit the use of Nafion membranes.…”

“…3 Therefore, developing a new low-cost polymer electrolyte membrane (PEM) with desired characteristics is becoming an imperative goal for the research community. 6 Chitosan (CS) has been broadly explored as a solid polymer electrolyte in different types of fuel cells such as DMFC and PEFC. 7,8 Polyelectrolytes and ion-solvating polymer composites are two further classes of solid polymer electrolytes.…”

Coaly Graphite as an Eco-Friendly Material in the Microporous Layer of Proton Exchange Membrane Fuel Cells

“…There are mainly four parts in PEM fuel cells, namely, the bipolar plate, PEM, CL, and GDL. Previous work on simultions , and experiments − have spared great effort for optimizing the structure of PEM fuel cells. Among them, the GDL provides sufficient support for the catalyst layer, conducts electrons, facilitates water removal, and ensures a uniform distribution of gases that come from the bipolar plate. − Traditionally, the GDL is composed of an MPL and a carbon paper substrate as the gas diffusion medium .…”