Abstract: A multi-layer diffusion medium substrate having improved mechanical properties is disclosed. The diffusion medium substrate includes at least one stiff layer and at least one compressible layer. The at least one stiff layer has a greater stiffness in the x-y direction as compared to the at least one compressible layer. The at least one compressible layer has a greater compressibility in the z direction. A method of fabricating a multi-layer diffusion medium substrate is also disclosed.

Abstract: A fuel cell microporous layer including a plurality of porous particles wherein at least 90% of intruded volume by mercury porosimetry is introduced into pore size diameters ranging from about 0.43 ?m to about 0.03 ?m.

Abstract: A fuel cell includes an anode layer, a polymeric ion conductive membrane disposed over the anode layer, a cathode layer disposed over the polymeric ion conductive membrane, and an effective amount of a reactive material that corrodes at a higher rate than support carbon in the cathode layer, anode layer, or both. The reactive material is either proximate to or distributed within the cathode catalyst layer. In a variation, reactive material is also included proximate to the anode layer.

Abstract: A diffusion media and a process for its fabrication are provided for addressing issues related to water management in electrochemical cells and other devices employing the diffusion media. In accordance with one embodiment of the present invention, a process for fabricating a diffusion media is provided. A diffusion media substrate is provided comprising a porous fibrous matrix defining first and second major faces. The substrate comprises an amount of carbonaceous material sufficient to render the substrate electrically conductive. A mesoporous layer is applied along at least a portion of one of the first and second major faces of the substrate. The mesoporous layer is applied to the substrate by providing a coating comprising a hydrophobic component, a hydrophilic component, and a pore forming agent. The substrate is free of fluorinated polymers outside of regions of the substrate carrying the mesoporous layer.

Abstract: A diffusion media and micro-porous media combination for a fuel cell. A diffusion layer is composed of a diffusion media and has a first (electrode) side and an opposite second (flowfield) side, wherein at least one of the first and second sides has a geometric pattern formed therein comprising a multiplicity of mutually spaced apart regions. A micro-porous media fills the multiplicity of regions and a micro-porous layer composed of the micro-porous media is continuously applied to the first surface.

Abstract: Ink dispersions for use in fuel cells, comprising a mixture of: (1) a carbon-containing material, such as carbon black; and (2) a base or acid operable to adjust the pH of the ink dispersion, wherein the pH of the mixture has a zeta potential as close to lying outside the +/?30 mV range of the point of zero charge. The mixtures can also include a fluoropolymer, at least one alcohol, and water. The ink dispersions can be used in conjunction with the gas diffusion media components of the fuel cell, including proton exchange membrane fuel cells. The ink dispersions are very stable and can be used in conjunction with high current density applications.

Abstract: A fuel cell substrate with an overcoat including an ionomer modified to include a cerium or manganese group and methods of making and using the same.

Abstract: A fuel cell microporous layer including a plurality of porous particles wherein at least 90% of intruded volume by mercury porosimetry is introduced into pore size diameters ranging from about 0.43 ?m to about 0.03 ?m.

Abstract: A diffusion media and a scheme for spatially varying the parameters of the diffusion media to address issues related to water management in electrochemical cells and other devices employing the diffusion media are provided. A device is configured to convert a hydrogenous fuel source to electrical energy and comprises an electrochemical conversion assembly, first and second reactant inputs, first and second product outputs, and first and second diffusion media. The device is configured such that a mesoporous layer is carried along at least a portion of a major face of one of the first and second diffusion media substrates. The mesoporous layer comprises a hydrophilic carbonaceous component and a hydrophobic component. The mesoporous layer occupies a substantially greater portion of one of the high or low H2O regions of the device, relative to the other of the high or low H2O region of the device.

Abstract: A fuel cell includes an anode layer, a polymeric ion conductive membrane disposed over the anode layer, a cathode layer disposed over the polymeric ion conductive membrane, and an effective amount of a reactive material that corrodes at a higher rate than support carbon in the cathode layer, anode layer, or both. The reactive material is either proximate to or distributed within the cathode catalyst layer. In a variation, reactive material is also included proximate to the anode layer.

Abstract: Specially prepared gas diffusion media improve the performance of PEM fuel cells. The media are made by first dipping an electrically conductive porous material such as carbon fiber paper into a suspension of hydrophobic polymer and drying the paper to create a desired deposition pattern of hydrophobic polymer on the substrate. Then a paste containing a fluorocarbon polymer and carbon particles is applied to a desired side of the substrate, and thereafter the paste and hydrophobic polymer are sintered together at high temperature on the paper. In particular, nonionic surfactants remain on the carbon fiber paper after the initial hydrophobic polymer is applied to the electrically conductive porous material. When the paste is coated on the dried paper, the paste is in contact with a hydrophilic surface.

Abstract: A diffusion media and a process for its fabrication are provided for addressing issues related to water management in electrochemical cells and other devices employing the diffusion media. In accordance with one embodiment of the present invention, a process for fabricating a diffusion media is provided. A diffusion media substrate is provided comprising a porous fibrous matrix defining first and second major faces. The substrate comprises an amount of carbonaceous material sufficient to render the substrate electrically conductive. A mesoporous layer is applied along at least a portion of one of the first and second major faces of the substrate. The mesoporous layer is applied to the substrate by providing a coating comprising a hydrophobic component, a hydrophilic component, and a pore forming agent. The substrate is free of fluorinated polymers outside of regions of the substrate carrying the mesoporous layer.