A fuel cell system includes: a fuel cell unit including first to nth fuel cells connected in series to each other to supply electric power to a load device; first to nth supply systems that independently supply cathode gas to the first to nth fuel cells, respectively; a switching device capable of switching a state between a connected state and a disconnected state; and a control unit, when required output to the fuel cell unit is equal to or smaller than a threshold value, configured to control the switching device to switch the state from the connected state to the disconnected state, and to control the first to nth supply systems to respectively control the first to nth fuel cells so as to respectively control flow rates of the cathode gas to be supplied to the first to nth fuel cells.

A vehicle includes at least one fuel cell stack, a water reservoir housed higher than the at least one fuel cell stack, a first water pump, a second water pump and a control module. The at least one fuel cell stack is operable to generate electrical energy and water. The water reservoir is operable to store water. The first water pump is operable to pump water from the at least one fuel cell stack into the water reservoir against gravity. The second water pump is operable to dispense water from the water reservoir under assistance from gravitational potential energy of water in the water reservoir. The control module is configured to operate the second water pump on an on-demand basis, and operate the first water pump on a time-selective basis.

A method of operating a power generation system, such as a fuel cell power generation system, includes providing a first electrical power up to a threshold amount of power to a load from at least one power module via a plurality of DC/DC converters and a DC power bus, determining whether electrical power from a utility is available, and providing a second electrical power from the at least one power module to a rectifier path via a plurality of DC/AC inverters in response to determining that the electrical power from the utility is available. The second electrical power includes electrical power generated by the at least one power module in excess of the threshold amount of electrical power.

A method of controlling a power supply system for an electric vehicle includes acquiring a first power setpoint value corresponding to the electrical power to be supplied by the battery, determining the electrical power required by the drivetrain and the electrical power required by the at least one auxiliary apparatus, determining the state of the battery, calculating at least one electrical power value to be delivered by the fuel cell, and calculating a second setpoint value for the electrical power to be delivered by the fuel cell. The second setpoint value is optimized so that the fuel cell operates at or near its maximum efficiency point.

A vehicle and method for operating a vehicle with a drivetrain including a fuel cell arrangement and a traction battery includes setting an upper threshold value for power output of the traction battery, determining a current maximum possible power request, determining the currently available power output of the fuel cell arrangement, determining the currently available power output of the traction battery up to the upper threshold value, and adjusting the upper threshold value for the permissible power output of the traction battery depending on the determined current maximum power request, the currently available power output of the fuel cell arrangement, and the currently available power output of the traction battery.

A redox flow battery includes a tank configured to store an electrolyte and a distribution mechanism to distribute the electrolyte to a battery cell. The tank has a partition portion partitioning a space inside the tank into a first space and a second space, the distribution mechanism has a distribution passage through which the electrolyte is distributed between the first space and the second space via the battery cell, and the partition portion is composed of a flexible material.

A power generation control system of a fuel cell includes: the fuel cell generating a power through a chemical reaction between fuel and air; a consuming device connected to an output terminal of the fuel cell and consuming the power output from the fuel cell; a converter connected between the fuel cell and the consuming device in series or parallel and adjusting an output voltage of the fuel cell; a supply device supplying the air to the fuel cell; a voltage controller controlling the converter on the basis of a required power or current of the fuel cell required to be output; and a supply controller controlling the supply device on the basis of the required power or current of the fuel cell required to be output.

A fuel cell system includes a fuel cell, a storage battery, a storage battery controller, an electric power demand predictor, and a fuel cell controller. The fuel cell controller calculates a full-charge necessary electric power amount, which is an amount of electric power necessary for fully charging the storage battery, by using a residual capacity and a first time, which is a time that is immediately before a time at which electric power demand becomes maximum among time at which predicted electric power demand and a fuel cell output become equal to each other. The fuel cell controller calculates a fuel cell adjustment output by dividing the full-charge necessary electric power amount by time from a present time to the first time, and controls the fuel cell with the calculated fuel cell adjustment output.

A fuel cell system and a control method thereof reduce a hydrogen exhaust amount and perform precise control in a low output section through the control of an air recirculation line and an air recirculation valve that recirculate the air discharged from the cathode of a fuel cell stack to the cathode.

A vehicle includes at least one fuel cell stack, a water reservoir housed higher than the at least one fuel cell stack, a first water pump, a second water pump and a control module. The at least one fuel cell stack is operable to generate electrical energy and water. The water reservoir is operable to store water. The first water pump is operable to pump water from the at least one fuel cell stack into the water reservoir against gravity. The second water pump is operable to dispense water from the water reservoir under assistance from gravitational potential energy of water in the water reservoir. The control module is configured to operate the second water pump on an on-demand basis, and operate the first water pump on a time-selective basis.