Evaluation of coated metallic bipolar plates for polymer electrolyte membrane fuel cells
- 作者：Wonseok Yoon ; Xinyu Huang ; Paul Fazzino ; Kenneth L. Reifsnider ; Michael A. Akkaoui
- 关键词：Fuel cells ; Metallic bipolar plates ; Coating ; Corrosion ; PVD
- 刊名：Journal of Power Sources
- 出版年：2008
- 期刊代码：58_03787753
- 类别：ce
- 出版时间：15 April 2008
- 卷：179
- 期：1
- 页码：265-273
- 文件大小：1867 K
摘要
Metallic bipolar plates for polymer electrolyte membrane (PEM) fuel cells typically require coatings for corrosion protection. Other requirements for the corrosion protective coatings include low electrical contact resistance, good mechanical robustness, low material and fabrication cost. The authors have evaluated a number of protective coatings deposited on stainless steel substrates by electroplating and physical vapor deposition (PVD) methods. The coatings are screened with an electrochemical polarization test for corrosion resistance; then the contact resistance test was performed on selected coatings. The coating investigated include Gold with various thicknesses (2 nm, 10 nm, and 1 μm), Titanium, Zirconium, Zirconium Nitride (ZrN), Zirconium Niobium (ZrNb), and Zirconium Nitride with a Gold top layer (ZrNAu). The substrates include three types of stainless steel: 304, 310, and 316. The results show that Zr-coated samples satisfy the DOE target for corrosion resistance at both anode and cathode sides in typical PEM fuel cell environments in the short-term, but they do not meet the DOE contact resistance goal. Very thin gold coating (2 nm) can significantly decrease the electrical contact resistance, however a relatively thick gold coating (>10 nm) with our deposition method is necessary for adequate corrosion resistance, particularly for the cathode side of the bipolar plate.