Abstract: A system and method for determining a maximum average cell voltage set-point for fuel cells in a fuel cell stack that considers oxidation of the catalyst in the fuel cells. The method includes determining the average cell voltage, the stack current density (I) and an internal resistance (R) of membranes in the fuel cells to calculate an IR corrected average cell voltage. The IR corrected average cell voltage is then used to determine the oxidation state of the catalyst particles using, for example, an empirical model. The oxidation state of the particles is then used to calculate the maximum average cell voltage set-point of the fuel cells, which is used to set the minimum power requested from the fuel cell stack.

Abstract: A system and method for determining a maximum average cell voltage set-point for fuel cells in a fuel cell stack that considers oxidation of the catalyst in the fuel cells. The method includes determining the average cell voltage, the stack current density (I) and an internal resistance (R) of membranes in the fuel cells to calculate an IR corrected average cell voltage. The IR corrected average cell voltage is then used to determine the oxidation state of the catalyst particles using, for example, an empirical model. The oxidation state of the particles is then used to calculate the maximum average cell voltage set-point of the fuel cells, which is used to set the minimum power requested from the fuel cell stack.

Abstract: A system and method for determining a maximum average cell voltage set-point for fuel cells in a fuel cell stack that considers oxidation of the catalyst in the fuel cells. The method includes determining the average cell voltage, the stack current density (I) and an internal resistance (R) of membranes in the fuel cells to calculate an IR corrected average cell voltage. The IR corrected average cell voltage is then used to determine the oxidation state of the catalyst particles using, for example, an empirical model. The oxidation state of the particles is then used to calculate the maximum average cell voltage set-point of the fuel cells, which is used to set the minimum power requested from the fuel cell stack.

Abstract: An MEA for a fuel cell that employs multiple catalyst layers to reduce the hydrogen and/or oxygen partial pressure at the membrane so as to reduce the fluoride release rate from the membrane and reduce membrane degradation. An anode side multi-layer catalyst configuration is positioned at the anode side of the MEA membrane. The anode side multi-layer catalyst configuration includes an anode side under layer positioned against the membrane and including a catalyst, an anode side middle layer positioned against the anode side under layer and not including a catalyst and an anode side catalyst layer positioned against the anode side middle layer and opposite to the anode side under layer and including a catalyst, where the amount of catalyst in the anode side catalyst layer is greater than the amount of catalyst in the anode side under layer.

Abstract: A system and method for determining a maximum average cell voltage set-point for fuel cells in a fuel cell stack that considers oxidation of the catalyst in the fuel cells. The method includes determining the average cell voltage, the stack current density (I) and an internal resistance (R) of membranes in the fuel cells to calculate an IR corrected average cell voltage. The IR corrected average cell voltage is then used to determine the oxidation state of the catalyst particles using, for example, an empirical model. The oxidation state of the particles is then used to calculate the maximum average cell voltage set-point of the fuel cells, which is used to set the minimum power requested from the fuel cell stack.

Abstract: A fuel cell including an anode-side catalyst coated diffusion medium and a cathode-side catalyst coated diffusion medium that sandwich an ionically conductive membrane. A sealing material is disposed between the ionically conductive membrane and the anode-side and cathode-side catalyst coated diffusion medium, wherein the sealing material is formed of a material that has a permeability that is less than a permeability of the ionically conductive member. The sealing material may also be formed of a material that is softer than the ionically conductive membrane such that the sealing material may deform and enable an membrane electrode assembly of the fuel cell to be subjected to uniform pressures throughout the assembly.

Abstract: A fuel cell including an anode-side catalyst coated membrane and a cathode-side catalyst coated membrane. At least a portion of a reduced-permeability layer is disposed between the ionically conductive membrane and the anode-side and cathode-side gas diffusion media, wherein the reduced-permeability layer is formed of a material that has a permeability that is less than a permeability of the ionically conductive member. The reduced-permeability layer may also be formed of a material that is softer than the ionically conductive membrane.

Abstract: The present invention is directed to addressing performance issues attributable to membrane electrode assemblies, and the components thereof, in electrochemical conversion cells. In accordance with one embodiment of the present invention, a device comprising at least one electrochemical conversion cell is provided. The cell is configured to convert first and second reactants to electrical energy and comprises a membrane electrode assembly and at least one membrane reinforcement layer. The combination of elastic modulus and thickness of the reinforcement layer and the bond between the reinforcement layer and the membrane electrode assembly are sufficient to enhance the structural integrity of the membrane electrode assembly beyond the operational degradation threshold of the assembly.

Abstract: A membrane electrode assembly including an ionically conductive member, an electrode, and an electrically conductive member including an active layer, wherein the electrode is a smooth, continuous layer that completely covers and supports the ionically conductive member. The electrode and active layer further include a first and second catalyst content, respectively; and 50% of the total catalyst content is present in the electrode and 50% of the total catalyst content is present in the active layer.

Abstract: A membrane electrode assembly comprising an ionically conductive member and an electrode, wherein the electrode is a smooth, continuous layer that completely covers and supports the ionically conductive member. The electrode further comprises a central region and a peripheral region, wherein a gradient of electrochemically active material exists between the central region and the peripheral region such that a content of the electrochemically active material is greater in the central region than the peripheral region.

Abstract: An MEA for a fuel cell that employs multiple catalyst layers to reduce the hydrogen and/or oxygen partial pressure at the membrane so as to reduce the fluoride release rate from the membrane and reduce membrane degradation. An anode side multi-layer catalyst configuration is positioned at the anode side of the MEA membrane. The anode side multi-layer catalyst configuration includes an anode side under layer positioned against the membrane and including a catalyst, an anode side middle layer positioned against the anode side under layer and not including a catalyst and an anode side catalyst layer positioned against the anode side middle layer and opposite to the anode side under layer and including a catalyst, where the amount of catalyst in the anode side catalyst layer is greater than the amount of catalyst in the anode side under layer.

Abstract: A method and system for detecting imperfections in a membrane electrode assembly of an electrochemical fuel cell, and more particularly for detecting defects within a proton exchange membrane in a membrane electrode assembly which is optionally sandwiched between conductive diffusion media layers or between conductive diffusion layers with at least one rigid solid that is transparent to infrared radiation. A potential voltage is applied across the membrane and the presence of a defect and preferably the location of a defect is determined by monitoring variations in intensity level of infrared radiation emitted from a surface of the membrane electrode assembly.

Abstract: A membrane electrode assembly comprising an ionically conductive member and an electrode, wherein the electrode is a smooth, continuous layer that completely covers and supports the ionically conductive member. The electrode further comprises a central region and a peripheral region, wherein a gradient of electrochemically active material exists between the central region and the peripheral region such that a content of the electrochemically active material is greater in the central region than the peripheral region.

Abstract: A membrane electrode assembly for a proton exchange membrane fuel cell that employs an improved catalyst. The catalyst is a mixture of a first catalyst and a second catalyst. The first catalyst is a 50 wt % Pt formed on Vulcan XC72 carbon having a BET surface area of about 250 m2/g. The second catalyst is a 50 wt % Pt formed on Ketjen Black carbon having a BET surface area of about 800 m2/g. The ratio of the first catalyst to the second catalyst is 1:1.

Abstract: A membrane electrode assembly for a proton exchange membrane fuel cell that employs an improved catalyst. The catalyst is a mixture of a first catalyst and a second catalyst. The first catalyst is a 50 wt % Pt formed on Vulcan XC72 carbon having a BET surface area of about 250 m2/g. The second catalyst is a 50 wt % Pt formed on Ketjen Black carbon having a BET surface area of about 800 m2/g. The ratio of the first catalyst to the second catalyst is 1:1.

Abstract: A membrane electrode assembly for a proton exchange membrane fuel cell that employs an improved catalyst. The catalyst is a mixture of a first catalyst and a second catalyst. The first catalyst is a 50 wt % Pt formed on Vulcan XC72 carbon having a BET surface area of about 250 m2/g. The second catalyst is a 50 wt % Pt formed on Ketjen Black carbon having a BET surface area of about 800 m2/g. The ratio of the first catalyst to the second catalyst is 1:1.

Abstract: A membrane electrode assembly comprising an ionically conductive member and an electrode, wherein the electrode is a smooth, continuous layer that completely covers and supports the ionically conductive member. The electrode further comprises a central region and a peripheral region, wherein a gradient of electrochemically active material exists between the central region and the peripheral region such that a content of the electrochemically active material is greater in the central region than the peripheral region.

Abstract: The present invention relates to a method and system for detecting imperfections in a membrane electrode assembly of an electrochemical fuel cell, and more particularly for detecting defects within a proton exchange membrane in a membrane electrode assembly, optionally sandwiched between conductive diffusion media layers, where a potential voltage is applied across the membrane and the presence of a defect and preferably the location of a defect is determined by monitoring variations in intensity level of infrared radiation emitted from a surface of the membrane electrode assembly. Another preferred embodiment includes sandwiching the membrane electrode assembly and conductive diffusion layers with at least one rigid solid that is transparent to infrared radiation.