Work

Modeling the performance of electrosprayed catalyst layers in the cathode of polymer electrolyte membrane fuel cells

Year: 2024

Type: article

Abstract: Electrosprayed catalyst layers (ES) have shown to be a viable route to improve the performance of polymer electrolyte membrane fuel cells (PEMFCs) due to their good ionic and mass transport properties. In this work, the behavior of ES cathode is examined numerically for the first time. A multiscale model accounting for macroscopic transport in the flow field and in the membrane electrode assembly (MEA) is coupled to a microscopic CL model. The results show that ES behavior can be explained by a particular multiscale arrangement of liquid water. ES reduces the tortuosity of the ionomer conduction network and promotes water uptake in ionomer. However, the higher water uptake is accompanied in ES by superhydrophobicity at macroscale ([[EQUATION]]) resulting from the dendritic morphology of the pore surface (Cassie-Baxter type). Superhydrophobicity reduces free liquid water in pores (i.e., liquid water not dissolved in ionomer), and thereby the oxygen transport resistance. As a result, performance is improved both under oxygen limiting condition and self-humidifying condition. In addition, the optimal ionomer mass fraction of ES is lower than conventional (0.15 vs. 0.3) and the ionomer distribution more uniform, leading to improved performance at low Pt loading.

Source: Fuel

DOI: 10.1016/j.fuel.2024.133175

Authors: Pablo A. García-Salaberri, Luis Duque, María Antonia Folgado, Ester Diaz-Alvarez, Antonio M. Chaparro

Institutions: Universidad Carlos III de Madrid, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas

Language: English

Topic: Fuel Cells and Related Materials

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

SDG: Affordable and clean energy

Open Access status: hybrid

Estimated APC paid: $4,200