PEMFC Metallic Bipolar Plates: Effect of Manufacturing Method on Corrosion Resistance

Abstract

Estimated high production volumes of bipolar plate manufacturing, strict dimensional and surface quality requirements and nature of their designs with thousands of meters of micro-channels demand engineers and scientists from production, design, and fuel cell operations sides look into alternative manufacturing processes, and compare their outcomes in terms of certain metrics such as productivity (plate/second), dimensional tolerances (um/mm), surface quality (Ra),cost ($), corrosion and contact resistance, and durability. In this study, the effect of manufacturing processes, stamping and hydroforming, on the corrosion resistance of thin metallic plates was investigated. The effects of process speed (stamping speed, hydroforming pressure rate) were also considered in this study. The results showed that in general SS316L possesses better corrosion resistance than SS304, as expected and reported in many literatures. In addition, while the effect of manufacturing processes was expected to degrade the corrosion resistance of the formed plates when compared the a non-deformed plate, this hypothesis only held true in the case of stamping as the hydroformed plates revealed better corrosion resistance than a non-deformed plate.