Optimization of hydrophobic additives content in microporous layer for air breathing PEMFC

Abstract

This study explored the ideal polytetrafluoroethylene (PTFE) content in the microporous layer (MPL) for proton exchange membrane fuel cells (PEMFCs) operating under specific conditions: room temperature, ambient pressure, and no-external humidification. The physical properties of MPL were evaluated through FE-SEM and contact angle measurements, and to understand how these properties affect the performance of MPL under unique operating conditions only dependent on internally generated water, the maximum power density at various PTFE contents was compared and electrochemically investigated. Both 5% and 20% PTFE contents exhibited superior performance, and the optimal PTFE content for passive-type cells was determined through performance and durability evaluations. These findings are expected to enhance fuel cell technology's suitability as a compact, portable power source and offer valuable operational insights. © 2023 Elsevier B.V.