The Centre for Process Innovation (CPI), a UK-based technology innovation center, Intelligent Energy and coatings supplier Haydale have been collaborating to develop novel, conductive coatings for proton exchange membrane (PEM) fuel cell bipolar plates with the goal of further cost reductions.
Intelligent Energy is leading this project in collaboration with CPI and the advanced coatings supplier Haydale to develop new conductive coatings containing nanocarbons to replace the more traditional physical vapor deposition (PVD) methods.
Conventional metallic PEM fuel cell bipolar plates usually require the application of an electrically conductive coating to minimize resistive losses. Such coatings are presently applied either in a batch or continuous process usually using a variety of highly technical processes including thermal spraying, CVD and, most often, PVD.
These approaches incur considerable cost; through labor associated with chamber loading and unloading, the process times required to achieve high vacuum, or through the capital investment required for continuous vacuum processing.
The 12-month NovCoat project has evaluated the technical feasibility and cost-saving opportunities of using low-cost, wet-coatings applied by high-throughput, ambient processes to replace PVD methods.
The project has developed advanced coatings utilizing functionalized nanocarbons (graphene and/or carbon nanotubes) as the primary electrically conducting component to improve z plane conductivity in line with US DOE automotive targets. These coatings were applied using roll-to-roll techniques to pre-coat low cost stainless steel foils, and post-coat after part fabrication. The electrical and physical properties of the resultant coating have now been evaluated.
The NovCoat project has successfully demonstrated the fabrication of nanocarbon coatings on stainless steel with performance similar to PVD coatings, and the feasibility of ambient, solution based roll-to-roll processes which will help drive output levels and permit major cost reduction.
This highly innovative project has both technical and commercial elements that are beyond state of the art. The commercial partners are exciting, high growth potential companies and have demonstrated functionalization, dispersion, formulation and coating capabilities to deliver the project effectively.—Dr Steve Devine, Principal Scientist - Nanomaterials & Composites at CPI