A coolant injection controller for a fuel cell system, the coolant injection controller configured to actively control the flow of a coolant to a fuel cell assembly for cooling and/or hydrating the fuel cell assembly in response to a measure of fuel cell assembly performance, wherein the coolant injection controller is configured to provide for a first mode of operation if the measure of fuel cell assembly performance is below a predetermined threshold and a second mode of operation if the measure of fuel cell assembly performance is above the predetermined threshold, the first and second modes having different coolant injection profiles and wherein, in the first mode of operation, the coolant injection profile provides for control of the flow of coolant by alternating between at least two different injection flow rates.

A method and apparatus for operating an intermediate-temperature solid-oxide fuel cell stack (10) with a mixed ionic/electronic conducting electrolyte in order to increase its efficiency. The required power output of the solid-oxide fuel cell stack (10) is determined and one or more operating conditions of the solid fuel cell stack (10) are controlled dependent upon the determined required power output. The operating conditions that are controlled may be at least one or the temperature of the fuel cell stack and the dilution of fuel delivered to the fuel cell stack.

An integrated fuel cell control system is provided. The integrated fuel cell control system includes at least one sensor, at least one hydrogen on/off valve, and a fuel control unit (FCU). The FCU is configured to directly operate the at least one sensor and the at least one hydrogen on/off valve in real time and to determine a supply pressure of hydrogen supplied to a fuel cell. Thereby, noise between controllers may be removed and costs may be reduced.

A fluid detection system and method for a fuel cell power plant is disclosed having a pressure sensor (61, 161) positioned in a fuel cell stack assembly (10) to measure pressure of fluid/liquid in a fluid/liquid flow path (40, 42, 44) therein and to provide a pressure-based signal (90, 63). The pressure-based signal (90, 63) is used to control a liquid management arrangement (53) at least during start-up and shut-down of the cell stack assembly (10) to regulate water level. The liquid management arrangement (53) may include means (50, 51) for controllably applying and releasing a vacuum to a water manifold (44, 54; 100) of the cell stack assembly (10) to regulate water flow and level therein. The pressure-based control of water level may extend across the entire operating range of the cell stack assembly (10), or may be complemented during steady state operation by voltage-based sensors (66, 166).

An apparatus for inspecting a stack assembly including a fluid channel through which fluid is supplied into fuel cell stacks includes a frame, a conveyor that is installed in the frame and that carries the stack assembly in a predetermined direction of movement to locate the stack assembly in a predetermined inspection position, a masking mechanism that is installed in the frame and that masks a fluid inlet and a fluid outlet of the stack assembly to seal the fluid channel of the stack assembly from outside the stack assembly, and a gas injection mechanism that is installed in the frame and that injects an inspection gas into the fluid channel of the stack assembly to inspect a sealing state of the fluid channel in the stack assembly, in a state in which the stack assembly is sealed by the masking mechanism.

A fuel cell system for a vehicle includes a first cooling line configured to pass through a fuel cell stack in a vehicle and configured to circulate a first coolant therein, a first cooler provided in the first cooling line and configured to cool the first coolant, and a second cooler provided in the first cooling line and configured to cool the first coolant independently from the first cooler, thereby obtaining an advantageous effect of ensuring a high output from the fuel cell stack and improving safety and reliability.

A thermal management system for a fuel cell vehicle includes a first line including a coolant pump and a fuel cell stack, a second line including a coolant heater and a phase change material (PCM) and connected to the first line to form a first loop in which the coolant pump, the stack, the coolant heater, and the PCM are arranged, a third line including a radiator and connected to the first line to form a second loop in which the coolant pump, the stack, and the radiator are arranged, and an opening and closing valve opening and closing each of the first line, the second line, and the third line to allow the coolant to circulate in at least one of the first loop and the second loop, wherein the PCM is configured to be heat-exchanged with the coolant heater and the coolant.

A fuel cell system includes a sensor device that measures a coolant temperature at an inlet of a fuel cell and an outside-air temperature, a cooling fan that cools a coolant, and a cooling fan controller connected with the sensor device and the cooling fan. The cooling fan controller determines an RPM of the cooling fan, based on the outside-air temperature and an output value of the fuel cell and corrects the RPM of the cooling fan, based on the coolant temperature at the inlet of the fuel cell.

Disclosed is a cooling module for use in a fuel cell system, the module includes a tank configured to receive a coolant therein, a coolant, a pump in fluid communication with the coolant in the tank and the fuel cell system, the pump being configured to transport the coolant to the fuel cell system, a heating element within the coolant in the tank, the heating element configured to heat the coolant, and at least one sensor in signal communication with a controller and in fluid communication with the tank. The sensor is configured to detect a change corresponding to the presence or absence of sufficient liquid coolant to initiate said pump, and the controller processes sensor data and is configured to actuate the pump.

A system of fuel cells for an aircraft includes a plurality of fuel cells, a hydrogen circuit, an air circuit, and a first cooling circuit configured to cool a first subset of cells including at least two cells. The first cooling circuit includes a computer-controlled device for mixing a first liquid coolant at a first temperature with a second liquid coolant at a second temperature lower than the first temperature to obtain a liquid coolant having a target temperature, a liquid coolant restrictor configured to distribute the liquid coolant between the cells of the first subset, and an outlet valve, the opening of which is controlled by the computer as a function of the cooling needs of the cells of the first subset. The use of a cooling circuit to cool several fuel circuits makes it possible to limit the bulk of the fuel cells system.