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DOE OSTI · 2204885

Coating developments towards enabling aluminum as a bipolar plate material for PEM fuel cells

Srivastava, Abhinav·Ross, Kenneth A.·Smith, Christopher B.
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Abstract

Bipolar plates represent a significant portion of the cost and weight of a proton exchange membrane fuel cell stack. As a result, there has been significant interest in using low weight and cost materials, such as aluminum. Aluminum has good mechanical and physical properties; however, it performs poorly in the corrosive environment within the fuel cell stack. To overcome the corrosion performance issue, there have been efforts towards developing coating processes to enable aluminum to attain corrosion targets. In an effort to enable aluminum as a viable bipolar plate material, a solid phase processing (diffusion bonding) approach for bonding a titanium foil to aluminum is investigated in this study. The microstructure, corrosion performance, mechanical properties and electrical resistance are investigated. To avoid the known reduction in contact resistance performance of titanium after exposure to bipolar plate media, the effect of addition of highly conductive gold particles after diffusion bonding, on contact resistance and corrosion behavior, is also studied and compared with diffusion bonded Ti to Al. In conclusion, the results indicate that diffusion bonded Ti to Al provides a viable alternative material combination for bipolar plate that avoids the micro pores and crevasses that are associated with vapor deposition or electroplating.

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25 ENERGY STORAGEPEMaluminumbipolar platesdiffusion bondingtitanium

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Srivastava, Abhinav, Ross, Kenneth A., Smith, Christopher B.. 2023-08-22. Coating developments towards enabling aluminum as a bipolar plate material for PEM fuel cells. https://doi.org/10.1016/j.jpowsour.2023.233513

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