A fuel cell vehicle includes a high voltage apparatus for a fuel cell, a compressor for an air conditioner disposed under the high voltage apparatus for the fuel cell and constituting a module integrated with the high voltage apparatus for the fuel cell, and a power control unit separated from the high voltage apparatus for the fuel cell, disposed at a vehicle body over the compressor and configured to control an operation of a motor. The compressor and the high voltage apparatus for the fuel cell are connected by a single power wiring.

A fuel cell stack includes a plurality of cell groups and a controller wherein each cell group comprises a plurality of fuel cells and a group sensor which measures one or more electrical characteristics of the respective cell group. The controller comprises one or more processors and memory and is communicatively coupled to each group sensor. The one or more processors execute machine readable instructions to compare a measured electrical characteristic of each cell group to one or more thresholds stored in memory, and indicate the need for diagnostics of the fuel cell stack when the comparison indicates a non-systemic event.

Systems and methods for detecting and validating a leak in a fuel cell system are presented. In certain embodiments, various fuel cell stack set points may be adjusted such that adequate H.sub.2 flow data may be obtained to identify and validate an H.sub.2 leak and/or a location of such a leak. In some embodiments, H.sub.2 flow data may be obtained by adjusting certain fuel cell system operating parameters under a variety of operating conditions and/or modes and measuring flow data under such various operational conditions.

Systems and methods for monitoring the isolation resistance of one or more fuel cells are described herein. In one example, a system includes a current transformer having a hollow core. First and second portions of a load line from a fuel cell are located within the hollow core. The first portion of the load line is electrically between an anode of a fuel cell and an electrical load, while the second portion of the load line being electrically between a cathode of the fuel cell and the electrical load. The current transformer is configured to output an electrical signal proportional to a current passing through the hollow core. This electrical signal can then be used to determine the isolation resistance of the fuel cell.

Systems and methods for fuel cell stack part serialization and tracking. In an embodiment, a barcode may be applied to a fuel cell stack part which may identify the fuel cell stack part. In an embodiment, the barcode may be applied as ink on a green fuel cell stack part prior to sintering. In an embodiment, a portion of a fuel cell stack part may be imaged and pattern recognition techniques may be utilized to identify the fuel cell stack part based on the unique features of fuel cell stack part. In an embodiment, portion of a fuel cell stack part may be measured to generate one or more series of unique volume/area values and one or more series of unique volume/area values may be utilized to identify the fuel cell stack part.

Systems and methods for fuel cell stack part serialization and tracking. In an embodiment, a barcode may be applied to a fuel cell stack part which may identify the fuel cell stack part. In an embodiment, the barcode may be applied as ink on a green fuel cell stack part prior to sintering. In an embodiment, a portion of a fuel cell stack part may be imaged and pattern recognition techniques may be utilized to identify the fuel cell stack part based on the unique features of fuel cell stack part. In an embodiment, portion of a fuel cell stack part may be measured to generate one or more series of unique volume/area values and one or more series of unique volume/area values may be utilized to identify the fuel cell stack part.

A startup control method of a fuel cell system includes initiating hydrogen supply to an anode, determining whether an opening degree of an air control valve (ACV having received a cut-off command, is less than or equal to a designated reference opening degree, driving an air compressor to supply bypass air, if the opening degree of the ACV is less than or equal to the reference opening degree, determining whether execution of startup cathode oxidation depletion (COD) is necessary, and if so, initiating the execution of the startup COD, and determining, depending on an integral value Q of current supplied from a fuel cell stack to a resistive electrical load, and an operating point in a current-voltage plane of a COD circuit, whether designated basic COD control, control focused on protection of the fuel cell system, or control focused on quick startup is necessary.

A control system for controlling a fuel cell system is provided, wherein the fuel cell system comprises a plurality of sub-units. The control system comprises a control unit being configured to control each of the sub-units individually.

Disclosed are an ionic conductivity measurement device and method for a fuel cell, which enable accurate measurement of ionic conductivity of a membrane electrode assembly for a fuel cell under various conditions. The ionic conductivity measurement device includes a main body frame, a clamp handle mounted to the upper portion of the main body frame, a lift shaft connected to the clamp handle so as to be movable upwards and downwards, a motion jig mounted to the main body frame so as to be movable upwards and downwards and including an upper support frame connected to the lower end of the lift shaft and a specimen support frame connected to the upper support frame, a lower support frame mounted to the lower end portion of the main body frame, an upper probe pin mounted to the upper support frame, and a lower probe pin mounted to the lower support frame.