Corrosion Study on Different Types of Metallic Bipolar Plates for Polymer Electrolyte Membrane Fuel Cells

Abstract

Three different types of metallic bipolar plates (commercial stainless steels, Ni-based alloys, and nitride-coated steels) were investigated in terms of their interface contact resistance (ICR) and corrosion resistance in conditions typical of a proton exchange membrane fuel cell environment. The results showed that stainless steels are unsuitable because of the formation of nonconductive oxide that leads to high ICR. Ni-based alloys showed to be prone to corrosion in acidic medium, although they have an ICR comparable to commercially available graphite. Endurance tests carried out on nitride-coated stainless-steel specimens showed a low ICR and very good corrosion resistance of this material.