Effect of micro-cracks on the in-plane electronic conductivity of proton exchange membrane fuel cell catalyst layers based on lattice Boltzmann method. (5th December 2022)

• Record Type: Journal Article
• Authors: Yang, Mingyang; Yan, Song; Du, Aimin; Liu, Jinling; Xu, Sichuan
• Is Part Of: International journal of hydrogen energy. Volume 47:Number 94(2022)
• Page Start: 39961
• Page End: 39972
• Publication Date: 2022-12-05
• Subjects: PEM fuel Cell -- Catalyst layer (CL) -- Micro-crack -- Lattice Boltzmann method (LBM) -- Conductivity; Hydrogen as fuel -- Periodicals; Hydrogène (Combustible) -- Périodiques; Hydrogen as fuel; Periodicals; 665.81
• DOI: 10.1016/j.ijhydene.2022.09.142
• Languages: English
• ISSNs: 0360-3199

Abstract

Abstract: Micro-cracks commonly occur on the catalyst layers (CLs) during the manufacturing of catalyst coated membranes (CCMs). However, the crack shape parameters effect on CLs in-plane (IP) electronic conductivity λ s is not clear. In this work, the relationship between crack parameters and the λ s is obtained based on the two-dimensional (2D) multiple-relaxation time (MRT) lattice Boltzmann method (LBM). The LBM numerical model is validated by the normalized λ s experiment applied on three different home-made cracked CLs, and the parameter study focus on crack width, length, quantity and phase angle are carried out. The results show that the decrease of λ s has different sensitivity | k | to the parameters above. The crack width has little effect on λ s decrease, and the | k w | is 0.038. However, crack arm length and quantity show more significant impact, which | k l | and | k N | are 0.753 and 0.725, respectively. The CLs with different crack propagation directions show significant anisotropy on λ s, and a 53.53% decrease in λ s is observed between 0° and 90° crack phase angle change. To manufacture a high electronic conductivity CL, crack initiation and migration mitigation are highly encouraged. Highlights: Crack parameters are defined in the catalyst layer for the first time. A homemade cracked domain reconstruction method is proposed. In-plane conductivity is investigated using the 2D MRT lattice Boltzmann method. Crack length and quantity show a more significant influence than crack width on in-plane conductivity.