Abstract: A cathode configured for use within a fuel cell system is provided. The cathode includes a cathode substrate. The cathode further includes a coating disposed upon the cathode substrate and including a fluorocarbon polymer additive configured for sintering at a temperature of less than 200° C. The fluorocarbon polymer additive may be mixed with a catalyst ink coating or may be applied separately as a topcoat layer.

Abstract: A cathode configured for use within a fuel cell system is provided. The cathode includes a cathode substrate. The cathode further includes a coating disposed upon the cathode substrate and including a fluorocarbon polymer additive configured for sintering at a temperature of less than 200° C. The fluorocarbon polymer additive may be mixed with a catalyst ink coating or may be applied separately as a topcoat layer.

Abstract: Systems, methods, fuel cells, and mixtures to inhibit ionomer permeation into porous substrates using a crosslinked ionomer are described. A method includes preparing an ionomer premix, mixing a crosslinking additive with the ionomer premix to thereby form a crosslinked-ionomer solution, and adding catalyst particles to the crosslinked-ionomer solution to produce a catalyst ink. The ionomer premix includes an ionomer dispersed within a solvent. The catalyst ink includes the catalyst particles distributed homogenously therethrough. The catalyst ink may be cast onto a porous substrate and dried to thereby form a catalyst layer for use in a fuel cell.

Abstract: Systems, methods, fuel cells, and mixtures to inhibit ionomer permeation into porous substrates using a crosslinked ionomer are described. A method includes preparing an ionomer premix, mixing a crosslinking additive with the ionomer premix to thereby form a crosslinked-ionomer solution, and adding catalyst particles to the crosslinked-ionomer solution to produce a catalyst ink. The ionomer premix includes an ionomer dispersed within a solvent. The catalyst ink includes the catalyst particles distributed homogenously therethrough. The catalyst ink may be cast onto a porous substrate and dried to thereby form a catalyst layer for use in a fuel cell.

Abstract: The present disclosure provides a method for manufacturing an integrated MEA, the method includes the following steps: (1) providing a substrate having an AA region and a WVT region; (2) coating a hydrophobic microporous layer across the substrate; (3) coating a catalyst layer onto the hydrophobic microporous layer in the AA region; (4) coating a first fuel cell membrane ionomer layer onto the catalyst layer in the AA region and onto the hydrophobic microporous layer in the WVT region; (5) optionally applying a membrane support layer to the first fuel cell membrane ionomer layer in the AA region and the WVT region; (6) optionally applying a coating of second fuel cell membrane ionomer layer thereby forming a coated substrate; and (7) assembling the coated substrate to a companion coated substrate.

Abstract: A controller-executed method for conditioning a membrane electrode assembly (MEA) in a fuel cell for use in a fuel cell stack includes humidifying a fuel inlet to the stack to a threshold relative humidity level, and maintaining a current density and cell voltage of the fuel cell at a calibrated current density level and hold voltage level, respectively, via the controller in at least one voltage recovery stage. The recovery stage has a predetermined voltage recovery duration. The method includes measuring the cell voltage after completing the predetermined voltage recovery duration, and executing a control action with respect to the fuel cell or fuel cell stack responsive to the measured cell voltage exceeding a target voltage, including recording a diagnostic code via the controller indicative of successful conditioning of the MEA. A fuel cell system includes the fuel cell stack and controller.

Abstract: The present disclosure provides a method for manufacturing an integrated MEA, the method includes the following steps: (1) providing a substrate having an AA region and a WVT region; (2) simultaneously coating a microporous layer, a catalyst layer, and a first membrane ionomer layer onto the substrate; (3) applying an optional membrane support layer to the first membrane ionomer layer in the AA region and the WVT region; (4) applying an optional second membrane ionomer layer; (5) heating treating a coated substrate; and (6) assembling the coated substrate to a companion coated substrate.

Abstract: A method of forming a catalyst layer for a fuel cell includes electrospinning a first solution of an ionomer, a binder, and a first solvent to form a porous mat having an interior and an exterior and including a plurality of ionomer nanofibers intertwined with one another to define a plurality of pores within the interior. A portion of the plurality of ionomer nanofibers define the exterior and have an internal surface facing the interior and an external surface facing away from the interior. The method also includes electrospraying a second solution of a catalyst and a second solvent onto the porous mat such that the catalyst is disposed on each external surface and is not embedded within the plurality of pores to thereby form the catalyst layer. A catalyst layer and a fuel cell are also described.

Abstract: The present disclosure provides a method for manufacturing an integrated MEA, the method includes the following steps: (1) providing a substrate having an AA region and a WVT region; (2) simultaneously coating a microporous layer, a catalyst layer, and a first membrane ionomer layer onto the substrate; (3) applying an optional membrane support layer to the first membrane ionomer layer in the AA region and the WVT region; (4) applying an optional second membrane ionomer layer; (5) heating treating a coated substrate; and (6) assembling the coated substrate to a companion coated substrate.

Abstract: An electrode ink composition that forms a fuel cell catalyst layer with reduced mudcracking is provided. The ink composition includes a solvent, a platinum group metal-containing catalyst composition dispersed in the solvent, a primary polymer dispersed within the solvent, the primary polymer being an ionomer, and a secondary polymer dispersed within the solvent, the secondary polymer interacting with the primary polymer via a non-covalent interaction.

Abstract: The present disclosure provides a method for manufacturing an integrated MEA, the method includes the following steps: (1) providing a substrate having an AA region and a WVT region; (2) coating a hydrophobic microporous layer across the substrate; (3) coating a catalyst layer onto the hydrophobic microporous layer in the AA region; (4) coating a first fuel cell membrane ionomer layer onto the catalyst layer in the AA region and onto the hydrophobic microporous layer in the WVT region; (5) optionally applying a membrane support layer to the first fuel cell membrane ionomer layer in the AA region and the WVT region; (6) optionally applying a coating of second fuel cell membrane ionomer layer thereby forming a coated substrate; and (7) assembling the coated substrate to a companion coated substrate.

Abstract: A controller-executed method for conditioning a membrane electrode assembly (MEA) in a fuel cell for use in a fuel cell stack includes humidifying a fuel inlet to the stack to a threshold relative humidity level, and maintaining a current density and cell voltage of the fuel cell at a calibrated current density level and hold voltage level, respectively, via the controller in at least one voltage recovery stage. The recovery stage has a predetermined voltage recovery duration. The method includes measuring the cell voltage after completing the predetermined voltage recovery duration, and executing a control action with respect to the fuel cell or fuel cell stack responsive to the measured cell voltage exceeding a target voltage, including recording a diagnostic code via the controller indicative of successful conditioning of the MEA. A fuel cell system includes the fuel cell stack and controller.

Abstract: Disclosed are fuel cell stack break-in procedures, conditioning systems for performing break-in procedures, and motor vehicles with a fuel cell stack conditioned in accordance with disclosed break-in procedures. A break-in method is disclosed for conditioning a membrane assembly of a fuel cell stack. The method includes transmitting humidified hydrogen to the anode of the membrane assembly, and transmitting deionized water to the cathode of the membrane assembly. An electric current and voltage cycle are applied across the fuel cell stack while the fuel cell stack is operated in a hydrogen pumping mode until the fuel cell stack is determined to operate at a predetermined threshold for a fuel cell stack voltage output capability. During hydrogen pumping, the membrane assembly oxidizes the humidified hydrogen, transports protons from the anode to the cathode across the proton conducting membrane, and regenerates the protons in the cathode through a hydrogen evolution reaction.

Abstract: Disclosed are fuel cell stack break-in procedures, conditioning systems for performing break-in procedures, and motor vehicles with a fuel cell stack conditioned in accordance with disclosed break-in procedures. A break-in method is disclosed for conditioning a membrane assembly of a fuel cell stack. The method includes transmitting humidified hydrogen to the anode of the membrane assembly, and transmitting deionized water to the cathode of the membrane assembly. An electric current and voltage cycle are applied across the fuel cell stack while the fuel cell stack is operated in a hydrogen pumping mode until the fuel cell stack is determined to operate at a predetermined threshold for a fuel cell stack voltage output capability. During hydrogen pumping, the membrane assembly oxidizes the humidified hydrogen, transports protons from the anode to the cathode across the proton conducting membrane, and regenerates the protons in the cathode through a hydrogen evolution reaction.

Abstract: An electrode ink composition that forms a fuel cell catalyst layer with reduced mudcracking is provided. The ink composition includes a solvent, a platinum group metal-containing catalyst composition dispersed in the solvent, a primary polymer dispersed within the solvent, the primary polymer being an ionomer, and a secondary polymer dispersed within the solvent, the secondary polymer interacting with the primary polymer via a non-covalent interaction.

Abstract: System and methods for detecting anode contamination in a fuel cell system are presented. In certain embodiments, a high frequency resistance response of a fuel cell system may be measured at a plurality of frequencies. In some embodiments, the rate of change of high frequency resistance response over time may differ at varied frequencies based on an amount of anode contamination in the fuel cell system. Accordingly, systems and methods disclosed herein may compare high frequency resistance responses taken at a plurality of measured frequencies to detect anode contamination and initiate associated recovery procedures in the fuel cell system.

Abstract: System and methods for reducing carbon corrosion in a fuel cell system are presented. Particularly, the disclosed systems and methods may be utilized in connection with preventing the formation of a propagating H2-Air interface within the fuel cell system. In certain embodiments, the disclosed systems and methods may utilize an electrochemical pump disposed in a cathode loop of the fuel cell system configured to remove oxygen that intrudes into the fuel cell system. In further embodiments, pumps may be included in an anode and a cathode loop of the fuel cell system that may allow for circulation of certain gases to prevent the formation of an H2-Air front with the system.

Abstract: System and methods for detecting anode contamination in a fuel cell system are presented. In certain embodiments, a high frequency resistance response of a fuel cell system may be measured at a plurality of frequencies. In some embodiments, the rate of change of high frequency resistance response over time may differ at varied frequencies based on an amount of anode contamination in the fuel cell system. Accordingly, systems and methods disclosed herein may compare high frequency resistance responses taken at a plurality of measured frequencies to detect anode contamination and initiate associated recovery procedures in the fuel cell system.

Abstract: A system and method for limiting voltage cycling of a fuel cell stack during a stand-by mode by providing power from a battery to the stack while the stack is turned off. The method includes monitoring the voltage of each of the fuel cells in the fuel cell stack and determining an average cell voltage of the fuel cells in the fuel cell stack. The method also determines whether the average cell voltage of the fuel cells in the fuel cell stack has fallen below a predetermined voltage value and, if so, applies a voltage potential to the fuel cell stack to increase the average cell voltage above the predetermined voltage value.

Abstract: A method of making a membrane electrode assembly for a fuel cell, a membrane electrode assembly, a fuel cell and a fuel cell system. The method includes preferentially adsorbing an ionomer and electrocatalyst mixture onto the surface of a porous fuel cell substrate by appropriate treatment of the mixture prior to or contemporaneous with placement of the mixture onto the substrate. This promotes retention of the ionomer-coated electrocatalyst at or near the surface of the substrate where catalytic activity between it and a proton exchange membrane is designed to take place. Retention of the ionomer-coated electrocatalyst near these interfacial regions by the present invention is preferable to having the ionomer and electrocatalyst be significantly absorbed into the substrate.