Abstract: The presently disclosed subject matter relates to devices, systems, and methods of producing an improved fluid flow assembly and liquid/gas diffusion layer in solid polymer electrolyte electrochemical cells. In one aspect, a fluid flow assembly for a polymer electrolyte water electrolyzer includes a flow field having an inlet, an outlet, and a plurality of discrete lands arranged within the flow field. A liquid/gas diffusion layer is positioned in communication with the flow field between the inlet and the outlet, the liquid/gas diffusion layer having a solid substrate through which a plurality of pores is formed. The disclosed bipolar plate flow field and liquid/gas diffusion layer could work together or separately with other types of porous transport layers or bipolar plates to enhance the water/gas transport. In these configurations, the lands can be arranged and configured such that the plurality of pores are substantially unobstructed by the lands.

Abstract: Methods, apparatuses and systems for detecting tampering are disclosed. The methods, apparatuses and systems for detecting tampering can involve positioning at least a portion of one or more ingress/egress line having a first end and a second end in a clamping box configured to provide detection of tampering; and detecting tampering by observing the clamping box.

Abstract: Methods, apparatuses and systems for detecting tampering are disclosed. The methods, apparatuses and systems for detecting tampering can involve positioning at least a portion of one or more ingress/egress line having a first end and a second end in a clamping box configured to provide detection of tampering; and detecting tampering by observing the clamping box.

Abstract: A flow battery having stable electrochemical performance is provided. The flow battery includes a separator disposed between a positive electrode and a negative electrode, a first flow plate to distribute a positive electrolyte to the positive electrode, and a second flow plate to distribute a negative electrolyte to the negative electrode. A material of at least one of the positive and negative electrodes is treated such that a surface area of the material when treated is greater than a surface area of the material when untreated. When the positive and negative electrolytes include vanadium ions, a concentration of vanadium in the positive electrolyte is different from a concentration of vanadium in the negative electrolyte to mitigate crossover-induced capacity fade.

Abstract: The present invention provides a method for removing residual water in a fuel cell, which controls the humidity of purge gases to effectively remove residual water in the fuel cell and to maintain the humidity in a membrane at a constant level, thus ensuring the durability of the membrane. For this purpose, the present invention provides a method for removing residual water in a fuel cell, characterized in that the relative humidities of purge gases supplied to an anode and a cathode are controlled to selectively reduce water content in the fuel cell and water content in a membrane.

Abstract: The present invention provides a fuel cell bipolar plate in which an air gap or a material layer having a heat transfer coefficient lower than that of the bipolar plate is provided so as to reduce total amount of liquid water generated in a fuel cell, thereby preventing the occurrence of flooding and reducing the time required for cold start, enhancing durability, decreasing parasitic purge requirements, and enhancing operational stability.

Abstract: A fuel cell comprises a cathode gas diffusion layer, a cathode catalyst layer, an anode gas diffusion layer, an anode catalyst layer and an electrolyte. The diffusion resistance of the anode gas diffusion layer when operated with anode fuel is higher than the diffusion resistance of the cathode gas diffusion layer. The anode gas diffusion layer may comprise filler particles having in-plane platelet geometries and be made of lower cost materials and manufacturing processes than currently available commercial carbon fiber substrates. The diffusion resistance difference between the anode gas diffusion layer and the cathode gas diffusion layer may allow for passive water balance control.

Abstract: The present invention provides a method for removing residual water in a fuel cell, which controls the humidity of purge gases to effectively remove residual water in the fuel cell and to maintain the humidity in a membrane at a constant level, thus ensuring the durability of the membrane. For this purpose, the present invention provides a method for removing residual water in a fuel cell, characterized in that the relative humidities of purge gases supplied to an anode and a cathode are controlled to selectively reduce water content in the fuel cell and water content in a membrane.

Abstract: The present invention provides an apparatus and method for purging residual water and hydrogen during shutdown of a fuel cell, which can reduce the time required for purging residual water and hydrogen during shutdown of a fuel cell by opening and closing outlet lines of an anode and a cathode in a short period of time using solenoid valves.

Abstract: The present invention provides a fuel cell bipolar plate in which an air gap or a material layer having a heat transfer coefficient lower than that of the bipolar plate is provided so as to reduce total amount of liquid water generated in a fuel cell, thereby preventing the occurrence of flooding and reducing the time required for cold start, enhancing durability, decreasing parasitic purge requirements, and enhancing operational stability.

Abstract: This invention relates to the field of fuel cell catalysts, and more particularly to fuel cell catalysts including carbon supports having compositions which comprise one or more transition metals in combination with nitrogen (e.g., a transition metal nitride) formed on or over the surface of a carbon support. The present invention also relates to methods for preparation of fuel cell catalysts. The present invention further relates to the use of fuel cell catalysts described herein in processes for the generation of electric power.