Investigation of the Structural Characteristics of the Gas Diffusion Layer Using Micro-X-Ray Computed Tomography

Qitong Shi ¹

C Feng ²

Bing Li ³

Pingwen Ming ³

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School of Electrical Engineering, Tongling University, Tongling 244061, China |

College of Materials Science and Engineering, Tongji University, Shanghai 201804, China |

School of Automotive studies, Tongji University, Shanghai 201804, China |

Publication type: Journal Article

Publication date: 2025-01-17

MDPI

Journal: Energies

scimago Q1

wos Q3

SJR: 0.651

CiteScore: 6.2

Impact factor: 3

ISSN: 19961073

DOI: 10.3390/en18020381

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Abstract

Due to its low stiffness, the gas diffusion layer (GDL) exhibits significant deformation under a compression service condition, thereby exerting a nonlinear and strong coupling influence on fuel cells’ performance. Therefore, it is of great practical significance to study the structural characteristics evolution of GDLs. The microstructure of the GDLs was obtained using micro-X-ray computed tomography in this study, and their structural properties were analyzed comprehensively and quantitatively. The morphology of GDLs exhibited significant variations across manufacturers due to disparities in the materials and manufacturing processes. The distribution of the pore equivalent diameter and sphericity in GDLs conformed to a normal distribution, with irregular shapes. The fiber length distribution in the unit followed a Gamma distribution, showing a random and uneven distribution in the XY plane. When compressed, the average fiber length was reduced, and a substantial increase in isolated pores was observed. However, the quantity of long fibers and connected and isolated pores decreased after acidification treatment.