Abstract: A separator assembly for use in a stack of electrochemical cells is provided, having a first conductive metallic substrate with a first surface and a second conductive metallic substrate with a second surface, wherein each of the first and second surfaces are overlaid with an ultra-thin electrically conductive metal coating. The first and second surfaces form electrically conductive paths at regions where the metal coating of the first and second layer contact one another. The contact of the surfaces overlaid with metal coating is sufficient to join the first and second substrates to one another. Preferred metal coatings comprise gold (Au). Methods of making such separator assemblies are also provided.

Abstract: A diffusion media is provided for implementation with a PEM fuel cell. The diffusion media is a permeable sheet that is rigid along a transverse axis, flexible along a lateral axis and has a substantially incompressible thickness. The diffusion media is able to be mass produced in large sheets and rolled along the lateral axis for transport and storage. The rigidity of the transverse axis is provided by either inclusion of larger fibers or metallic strips aligned in the transverse direction and prevents tenting of the diffusion media into flow channels of the PEM fuel cell. The diffusion media is water and gas permeable and electrically conductive.

Abstract: The present invention provides an electrically conductive element for a proton exchange membrane fuel cell having low electrical contact resistance and high corrosion resistance. The conductive element comprises a corrosion susceptible metal substrate with a surface, which is preferably treated to activate the surface (i.e., to remove a passivation layer of oxides from the surface) with an acidic treatment solution. The treated surface is then overlaid with an electrically conductive, corrosion-resistant, protective coating to protect the substrate re-forming a passivation layer while exposed to the corrosive environment of the fuel cell. The present invention also provides methods of preparing an electrically conductive element to have low electrical contact resistance and high corrosion resistance.

Abstract: The present invention relates to an electrically conductive element (e.g. bipolar plate) for a fuel cell which has an improved adhesive bond. The conductive element generally comprises a first and a second conductive sheet, each having a surface that confront one another. The surfaces that confront one another are overlaid with an electrically conductive primer coating providing corrosion protection and low contact resistance to said first and said second sheets respectively in regions where the first and second sheets contact one another. The first and said second coated surfaces are joined to one another by an electrically conductive adhesive which provides adhesion of said first and said second coated surfaces of said sheets at the contact region. Further, the present invention contemplates methods to form such an improved bond in an electrically conductive element.