Abstract: In one example, a specimen is immersed in an electrolyte, and a plurality of potentials of the specimen are experimentally related to a plurality of currents by applying the potentials to the specimen while measuring the currents, or, by drawing the currents through the specimen while measuring the potentials. The potentials are referenced to a hydrogen reference electrode. Hydrogen is supplied to the hydrogen reference electrode via an electrolysis cathode distinct from the hydrogen reference electrode. In another example, an electrochemical cell confines a head gas disposed over the electrolyte. A partial pressure of water vapor in the head gas is adjusted so that the concentration of water in the electrolyte, when equilibrated with the head gas, falls within a predetermined concentration range. The head gas and electrolyte are then equilibrated, thereby controlling the concentration of water in the electrolyte, and an electrochemical property of the specimen is measured.

Abstract: Embodiments are disclosed that relate to preventing electrolyte wicking by bipolar plates in a fuel cell system. In one example, a fuel cell system includes a first membrane-electrode assembly and a second membrane-electrode assembly. The fuel cell system further includes a bipolar plate disposed between the first membrane-electrode assembly and the second membrane-electrode assembly, the bipolar plate comprising a graphite layer and a surface energy adjustment layer.

Abstract: Embodiments are disclosed herein that relate to PEM fuel cells comprising membrane-electrode assemblies having plural membrane layers. For example, one disclosed embodiment provides a fuel cell including an anode, a cathode, and a multi-layer membrane disposed between the anode and the cathode, the multi-layer membrane comprising two or more polymer membranes layers. The fuel cell further comprises an electrolyte within the multi-layer membrane.

Abstract: A method for controlling an amount of a liquid electrolyte in a polymer-electrolyte membrane of a fuel cell is provided. The method comprises enriching one or more of a fuel flow and an air flow with a vapor of the liquid electrolyte, the liquid electrolyte being unreplenishable via an electrochemical reaction of the fuel cell. The method further comprises delivering the vapor of the liquid electrolyte to the fuel cell including the polymer-electrolyte membrane via one or more of the gas-permeable anode and or the gas-permeable cathode. In this manner, loss of liquid electrolyte from the PEM membrane of the fuel cell can be reduced, leading to improved fuel-cell endurance.

Abstract: A method for controlling an amount of a liquid electrolyte in a polymer-electrolyte membrane of a fuel cell is provided. The method comprises enriching one or more of a fuel flow and an air flow with a vapor of the liquid electrolyte, the liquid electrolyte being unreplenishable via an electrochemical reaction of the fuel cell. The method further comprises delivering the vapor of the liquid electrolyte to the fuel cell including the polymer-electrolyte membrane via one or more of the gas-permeable anode and or the gas-permeable cathode. In this manner, loss of liquid electrolyte from the PEM membrane of the fuel cell can be reduced, leading to improved fuel-cell endurance.

Abstract: A method for controlling an amount of a liquid electrolyte in a polymer-electrolyte membrane of a fuel cell is provided. The method comprises enriching one or more of a fuel flow and an air flow with a vapor of the liquid electrolyte, the liquid electrolyte being unreplenishable via an electrochemical reaction of the fuel cell. The method further comprises delivering the vapor of the liquid electrolyte to the fuel cell including the polymer-electrolyte membrane via one or more of the gas-permeable anode and or the gas-permeable cathode. In this manner, loss of liquid electrolyte from the PEM membrane of the fuel cell can be reduced, leading to improved fuel-cell endurance.

Abstract: In one embodiment, a method of making an MEA for a fuel cell comprises arranging a cathodic structure on a first surface of a PEM, and arranging an anodic structure on a second surface of the PEM, opposite the first surface, the anodic structure containing more PA per unit volume than the cathodic structure. The method further comprises pressing the cathodic and anodic structures to the PEM to form the MEA.

Abstract: In one example, a specimen is immersed in an electrolyte, and a plurality of potentials of the specimen are experimentally related to a plurality of currents by applying the potentials to the specimen while measuring the currents, or, by drawing the currents through the specimen while measuring the potentials. The potentials are referenced to a hydrogen reference electrode. Hydrogen is supplied to the hydrogen reference electrode via an electrolysis cathode distinct from the hydrogen reference electrode. In another example, an electrochemical cell confines a head gas disposed over the electrolyte. A partial pressure of water vapor in the head gas is adjusted so that the concentration of water in the electrolyte, when equilibrated with the head gas, falls within a predetermined concentration range. The head gas and electrolyte are then equilibrated, thereby controlling the concentration of water in the electrolyte, and an electrochemical property of the specimen is measured.

Abstract: A method for controlling an amount of a liquid electrolyte in a polymer-electrolyte membrane of a fuel cell is provided. The method comprises enriching one or more of a fuel flow and an air flow with a vapor of the liquid electrolyte, the liquid electrolyte being unreplenishable via an electrochemical reaction of the fuel cell. The method further comprises delivering the vapor of the liquid electrolyte to the fuel cell including the polymer-electrolyte membrane via one or more of the gas-permeable anode and or the gas-permeable cathode. In this manner, loss of liquid electrolyte from the PEM membrane of the fuel cell can be reduced, leading to improved fuel-cell endurance.