Design and development of gas diffusion layers with pore forming agent for proton exchange membrane fuel cells at various relative humidity conditions

• Published in: International journal of hydrogen energy 2021-02, Vol.46 (9), p.6835-6844
• Main Authors: Athanasaki, G., Wang, Q., Shi, X., Chauhan, N., Vimala, V., Cindrella, L., Ahmad, R., Kannan, A.M.
• Format: Article
• Language: English
• Subjects: Carbon; Contact angle; Design and Development; Diffusion in gases; Fuel cell performance; Gas diffusion layer; Gas diffusion layers; Higher relative humidity; Humidity conditions; Membrane electrode assemblies; Membrane-electrodes assembly; Microporous layer; Morphology; PEM Fuel cell; Pore-forming agents; Proton exchange membrane fuel cell (PEMFCs); Proton exchange membrane fuel cells (PEMFC); PUREBLACK; Scanning electron microscopy; Surface morphology
• ISSN: 0360-3199; 1879-3487; 1879-3487
• DOI: 10.1016/j.ijhydene.2020.11.187

Membrane electrode assemblies are developed by incorporating gas diffusion layers (GDL) to improve the lower and higher relative humidity performance of proton exchange membrane fuel cells (PEMFCs). In the present study, gas diffusion layer samples containing microporous layers, are fabricated using carbon paper substrate, PUREBLACK® carbon powder and polyethylene glycol as pore forming agent. The GDLs are studied in single cell fuel cell, to evaluate the effect of porosity of the micro-porous layer on the performance at different operating relative humidity conditions and compared with commercial GDLs. Scanning electron microscopy and contact angle measurements indicate crack-free surface morphology and hydrophobic characteristics of the PUREBLACK® based GDLs, respectively. By varying the wt. % of PEG, fuel cell performance is evaluated under relative humidity conditions of 60 and 100% using H2/O2 and H2/Air at 70 °C and the durability is also evaluated for the GDL samples without and with 30% PEG. The fuel cell performance of the GDL with 30% pore forming agent (with a pore volume of 1.72 cc.g−1) exhibited higher performance (444 and 432 mW cm−2 at 60 and 100% RH conditions, respectively using H2 and air) compared to that without pore forming agent (436 and 397 mW cm−2). •Microporous layers using PUREBLACK carbon on carbon paper substrate.•Polyethylene glycol as the pore forming agent for gas diffusion layers.•Fuel cell performance under various relative humidity conditions.•Enhancement of polarization and durability curves by optimizing porosity.