Abstract: A fuel-cell stack including treated bipolar plates is disclosed, as well as methods of treatment. The bipolar plates may include an active region wherein a fuel-cell reaction is configured to occur and an inactive region configured to supply, collect, and remove fluids from the active region. The inactive region may include one or more exit vias defined by the bipolar plate and having an inner surface configured to contact fluids received from the active region. At least a portion of the inner surface may have a hydrophobic textured surface. The methods may include treating a metal inner surface of an exit via defined in an inactive region of a fuel-cell bipolar plate that is configured to contact fluids received from an active region of the fuel-cell bipolar plate. The treatment may include removing material to form a hydrophobic textured surface on at least a portion of the inner surface.

Abstract: The present disclosure includes fuel cell bipolar plates and methods of forming a radical scavenging coating on a bipolar plate. The bipolar plates may include a steel substrate, a middle layer contacting the steel substrate and including a bulk material and a radical scavenging material, and a conductive layer contacting the middle layer. The radical scavenging material may include cerium, such as metallic cerium or a cerium oxide. The conductive layer may include a conductive carbon, such as a diamond-like carbon or coating (DLC). The radical scavenging material may comprise 0.1 wt % to 30 wt % of the middle layer. The middle layer may be deposited using PVD, and the radical scavenging material may be doped into the middle layer, for example, by co-sputtering it with the bulk material of the middle layer.

Abstract: The present disclosure includes a fuel cell bipolar plate including a coating and methods for forming the coating. The bipolar plate may include a steel substrate and a coating contacting the steel substrate. The coating may include a plurality of alternating oxide-forming layers and elution resistant layers. The oxide-forming layers may include pure titanium, doped titanium, or a titanium alloy (e.g. doped/alloyed with niobium, zirconium, vanadium, silver, tantalum, yttrium, scandium, or nitrogen) and the elution resistant layers may include a noble metal or tantalum (e.g., gold, iridium, ruthenium, or tantalum). There may be 2-20 layers each of the oxide-forming layers and the elution resistant layers. The coating may prevent elution of iron ions from the steel substrate, for example, by forming oxide plugs in defects or pinholes in the oxide forming and/or elution resistant layers. The coating may also reduce the total usage of precious metals, such as gold.

Abstract: A metal-ion battery includes an anode assembly and a cathode assembly ionically coupled by an electrolyte. The anode assembly includes a current collector and an anode material capable of intercalation of metal-ions. When the battery is at rest, ionic transfer between the anode and cathode at a minimum and the anode assembly potential with respect to the electrolyte may increase. The increased potential may exceed the reduction potential of the current collector material causing ions to erode from the current collector and contaminate the cathode. The use of a metal, metal alloy or metal compound reduces the rest potential and erosion of the current collector. For example, a lithium foil physically in contact with a copper current collector in a lithium-ion battery reduces the overall anode potential thereby reducing copper dissolution.