Variation in performance and characteristics of long-term operated gas diffusion layer in a fuel cell electric vehicle

Abstract

Proton-exchange membrane fuel cells (PEMFCs) operate at low temperatures and are used in household appliances and vehicles because of their high power density and fast start-up/shut-down capabilities. Previous research has focused on improving the performance of PEMFCs by enhancing their structures and constituent materials of their components. However, as PEMFCs are being commercialized, their durability remains a critical challenge that needs to be addressed. Although numerous studies have evaluated the durability of membrane electrode assemblies (MEA), limited research has been conducted on the durability of gas diffusion layers (GDL). The GDL, with its nanometer-to micrometer-sized pores and thickness of hundreds of microns, is prone to mechanical degradation during long-term operation. Moreover, the GDL is susceptible to carbon corrosion because it primarily consists of carbon materials, similar to the catalyst layer. Therefore, to ensure the performance and longevity of PEMFCs, it is of utmost importance to investigate the durability of the GDL. This study quantitatively investigates the variations in the performance and mechanical and chemical characteristics of GDLs during an extended period of operation in a fuel cell electric vehicle (FCEV), and two types of GDLs are analyzed.