Investigation on the physical and electrochemical properties of typical Ni-based alloys used for the bipolar plates of proton exchange membrane fuel cells

Jiacheng Zhong; Beirui Hou; Wenmin Zhang; Zhansheng Guo; Chunwang Zhao

doi:10.1016/j.heliyon.2023.e16276

Investigation on the physical and electrochemical properties of typical Ni-based alloys used for the bipolar plates of proton exchange membrane fuel cells

Heliyon. 2023 May 15;9(5):e16276. doi: 10.1016/j.heliyon.2023.e16276. eCollection 2023 May.

Authors

Jiacheng Zhong¹, Beirui Hou¹, Wenmin Zhang¹, Zhansheng Guo², Chunwang Zhao^{1

3}

Affiliations

¹ School of Materials Science and Hydrogen Energy, Foshan University, Foshan 528000, China.
² School of Mechanics and Engineering Science, Shanghai University, Shanghai 200072, China.
³ Guangdong Key Laboratory for Hydrogen Energy Technologies, Foshan, 528000, China.

Abstract

The phase, mechanical properties, corrosion resistance, hydrophobicity, and interface contact resistance of three typical Ni-based alloys (Hastelloy B, Hastelloy C-276, and Monel 400) and 304 stainless steels were experimentally studied to evaluate their service performances as bipolar plate materials of proton exchange membrane fuel cells. All four alloys exhibit single-phase face-centered cubic structure, high strength, good ductility, and high hardness. Hastelloy C-276 has the best ductility with an uniform elongation of 72.5% and highest hardness of 363.7 HV. Hastelloy B has the highest ultimate tensile strength of 913.6 MPa. The hydrophobicity of all four alloys is not good, although Monel 400 has the highest water contact angle of 84.2°. Hastelloy B, Hastelloy C-276, and 304 stainless steel exhibit unsatisfying corrosion resistance in a simulated acidic work environment of proton exchange membrane fuel cell (0.5 M H₂SO₄+2 ppm HF, 80 °C, H₂) and high interface contact resistance. By contrast, Monel 400 demonstrates excellent corrosion resistance with a corrosion current density of 5.9 × 10^-7 A cm^-2 and a low interface contact resistance of 7.2 mΩ cm² at 140 N/cm². In terms of comprehensive performance, Monel 400 is the best uncoated material for the bipolar plates of proton exchange membrane fuel cells among typical Ni-based alloys.

Keywords: Corrosion resistance; Hardness; Hydrophobicity; Interfacial contact resistance; Tensile strength.