Flexible Barrier Coatings for Harsh Environments

There is a need to reduce the cost and improve the reliability of hydrogen fuel cell electric vehicles (FCEVs) and their supporting infrastructure to enable FCEV competitiveness. Many reliability problems stem from plastic and elastomer seals employed in hydrogen systems that leak and degrade as a result of the extreme temperature and high pressure hydrogen environments. There is a critical need for improved materials are needed that can enable seals to operate reliably at both extreme temperatures (-40T200C) and high hydrogen pressures (>875 bar). GVD Corporation proposes to utilize hydrogen gas barrier coatings deposited on such seals to shield them from hydrogen permeation and enable reliable, long-term operation. These barrier coatings are based on GVDs novel thin film vapor deposition technology. In GVDs process an inorganic-organic multilayer barrier coatings are fabricated from the vapor-phase and is grown directly on the surface of the elastomer seal. The coating deposits uniformly and conformally over three-dimensional seals and gaskets. Further these coatings are highly flexible and stable at 200C. In Phase I, GVD demonstrated technical feasibility of the concept by depositing flexible, well adhered barrier coating stacks on elastomeric substrates. These coatings survived temperatures up to 200oC while reducing permeability to helium by >50% (equivalent to a 70-90% reduction in hydrogen permeability). During Phase II, GVD will optimize these materials for ease of manufacturing. Demonstration of resistance to high-pressure hydrogen permeability will be shown directly. The deposition process will be scaled up and a production tool designed to handle significant product volumes. In addition, prototype seals will be coated and tested at the bench level by a hydrogen compressor manufacturer and in the field by an industrial user of FCEVs. GVD has also already secured commitment from a commercial partner to bring this technology to market through an existing sales and marketing agreement. Commercial Applications and other Benefits. FCEVs have the potential to significantly reduce US dependence on foreign oil and lower harmful emissions that contribute to climate change. Successful commercialization of GVD barrier coatings for polymer seals will help improve reliability and reduce cost of hydrogen systems employed in FCEVs and their supporting infrastructure. GVD barrier-coated seals developed during this project may also be useful for equipment used in the oil and gas industry and for organic electronic devices such as organic light emitting diodes (OLEDs) and organic photovoltaics (OPVs).