Modelling and analysis on effects of penetration of microporous layer into gas diffusion layer in PEM fuel cells: Focusing on mass transport

The penetration of microporous layers (MPL) into gas diffusion layers (GDL) is a common phenomenon in proton exchange membrane (PEM) fuel cells. However, research on this phenomenon is few and its influence law and mechanism need to be further investigated. In this study, a three-dimensional, multiphase and non-isothermal fuel cell model is established to investigate the effects of penetration ratio, total thickness of GDL and transition region (TR) and operating pressure on fuel cells' mass transport and performance. The results show that, under high output voltage, performance increases as the increase of penetration ratio. Under low output voltage, 15% penetration ratio achieves the best fuel cell performance. In addition, 15% penetration ratio attains the lowest average membrane electrode assembly ohmic resistance, GDL and TR thicknesses and operating pressures. The existence of TR changes the liquid distribution; saturation decreases from the GDL side to the MPL side. Moreover, the penetration affects the membrane water content, and its distribution becomes more non-uniform as penetration ratio increases. (C) 2022 Published by Elsevier Ltd.

Automated summary

This study investigates the effects of penetration ratio, total thickness of GDL and transition region (TR), and operating pressure on the mass transport and performance of fuel cells using a three-dimensional, multiphase, and non-isothermal fuel cell model. The results show that the performance of fuel cells increases with the increase of penetration ratio under high output voltage. Under low output voltage, a penetration ratio of 15% achieves the best fuel cell performance. The existence of a transition region changes the liquid distribution, and the penetration affects the membrane water content, resulting in a more non-uniform distribution as the penetration ratio increases.