An energy storage system includes a vanadium redox battery that interfaces with a control system to optimize performance and efficiency. The control system calculates optimal pump speeds, electrolyte temperature ranges, and charge and discharge rates. The control system instructs the vanadium redox battery to operate in accordance with the prescribed parameters. The control system further calculates optimal temperature ranges and charge and discharge rates for the vanadium redox battery.

A fuel cell system includes: an external load connected to a fuel cell; an electric power adjusting unit configured to adjust a generated electric power of the fuel cell in accordance with electric power consumption of the external load; a humidity control unit configured to control humidity of an electrolyte membrane in the fuel cell on the basis of the generated electric power of the fuel cell; an output voltage detecting unit configured to detect an output voltage of the fuel cell; and a cross leakage determining unit configured to cause the humidity control unit to increase the humidity of the electrolyte membrane when the fuel cell generates the electric power, the cross leakage determining unit being configured to determine whether a cross leakage amount increases or not on the basis of a change in the output voltage at that time.

A fuel-cell system at 540 VDC for powering an electrical load of a rotorcraft with a first fuel cell and a second fuel cell. Each fuel cell is configured identically and features a positive electrical node and a negative electrical node. Each fuel cell is configured to provide one half of the electrical load of the rotorcraft and one half of the voltage of the electrical load.

To provide a fuel cell system capable of evaluating degradation of an electrolyte membrane by quantifying metal ions involved in degradation of an electrolyte membrane instead of evaluating degradation of an electrolyte membrane itself. A fuel cell system comprising a fuel cell, a fuel gas system for supplying fuel gas to an anode of the fuel cell, an oxidant gas system for supplying oxidant gas to a cathode of the fuel cell, a voltage detector for detecting a voltage of the fuel cell, and a controller.

Accelerated testing protocols that can be utilized for determining and projecting the durability of SOFC cathodes are described. The accelerated testing protocols can be carried out under simulated operation conditions so as to provide in a matter of a few hundred hours data that can correlate to the condition of the cathode following operation of the cell over the course of a typical operation life span of several thousand hours. A testing protocol can include cycling a SOFC from OCV to operating potential at a predetermined current density. Each cycle can be relatively short, for instance less than one minute.

A fuel cell unit has a structure that enables the maximum use of a cell monitor in the height direction (vertical direction). In order to achieve this, the fuel cell unit comprises a fuel cell stack (3) including a cell stack body in which unit cells are stacked; and a cell monitor (6) for monitoring a voltage of the unit cells, wherein the cell monitor (6) is arranged so as to be inclined relative to a vertical direction. The cell monitor is inclined by providing a part of the cell monitor in the vicinity of a heat-generating part in a fuel cell on an opposite side of the heat-generating part relative to a central part in the vertical direction of the cell monitor and providing a part of the cell monitor in an area other than the heat-generating part in the fuel cell on a heat-generating part side relative to the central part in the vertical direction of the cell monitor.

Provided are a recovery control system of a fuel cell and a method thereof. The recovery control system includes the fuel cell, a hydrogen supplier configured to supply hydrogen to the fuel cell, an air supplier configured to supply air to the fuel cell, an abnormality sensing unit configured to calculate a difference between a reference cell voltage predetermined depending on an output current of the fuel cell and a measured cell voltage of unit cells and to sense abnormality of air supply to a fuel cell stack based on the calculated difference between the reference cell voltage and the measured cell voltage or change in the difference, and a recovery controller configured to control the air supplier so as to increase a flow rate of air supplied to the fuel cell stack based on the change in the difference, when the abnormality sensing unit senses abnormality of air supply.

A method of operating a fuel cell assembly comprising a plurality of fuel cells connected together for collectively providing power to a load, each fuel cell including an anode and a cathode, the method comprising selectively providing an electrical connection between the anode and the cathode of at least one of the fuel cells of the assembly for lowering the voltage across the fuel cell independent of the load.

A system for measuring a moisture content of an ion-exchange membrane in a fuel-cell stack is provided. The fuel-cell stack includes N electrochemical cells separated by bipolar plates, with N being a natural integer. The system includes a current generator, a voltage measurement device, and an impedance measurement device. The current generator enables a current to be applied to the fuel-cell stack. The voltage measurement device measures voltages of the cells of the fuel-cell stack. The impedance measurement device determines an impedance of an ion-exchange membrane according to a voltage ripple measured by the voltage measurement device across terminals of a corresponding one of the cells of the fuel-cell stack when the current is applied by the current generator. The impedance measurement device is installed in the voltage measurement device.

An electrical system includes a stack (3) of electrochemical cells (5), a power converter (9) electrically connected to the stack (3), a voltage comparator (7) for comparing the voltage at the terminals of at least one group of at least one electrochemical cell (5) of the stack (3) to a threshold voltage, and a control module (11) for controlling the converter (9). The control module (11) includes a generator (74) for generating a control instruction for controlling the converter (9) and a transmission member (76) for transmitting the control instruction to the converter (9). The voltage comparator (7) is suitable for transmitting a signal to the transmission member (76). The signal consists of a first instruction from an instruction for transmitting and an instruction for blocking the control instruction when the compared voltage is higher than the threshold voltage, and a second instruction from the instructions for transmitting and blocking the control instruction when the compared voltage is lower than or equal to the threshold voltage.