A cooling control method of a fuel cell is provided. The method includes estimating a temperature of a separator based on heat exchange between the separator formed between unit cells of a fuel cell stack and coolant flowing through a cooling line between the separators. A ratio of coolant passing through a heat exchange device to coolant bypassing the heat exchange device is adjusted based on the estimated temperature of the separator. Additionally, a rotation speed of a pump for circulating coolant for cooling the fuel cell stack is adjusted based on the estimated temperature of the separator.

A fuel cell system capable of improving the chemical durability of a membrane electrode assembly by compensating for the amount of an antioxidant lost within the electrolyte membrane or electrode of the fuel cell stack in such a manner that the antioxidant is provided from an antioxidant supply device, provided in a fuel processing system and/or an air processing system, to a fuel cell stack, in preparation for a case where the antioxidant within the electrolyte membrane or electrode is lost due to the dissolution or migration characteristic of the antioxidant.

A fuel cell cooling system mounted on a vehicle includes a flow path for a coolant; a cooling unit that cools the coolant in a cooling unit flow path; a fuel cell to be cooled through heat exchange with the coolant in a fuel cell flow path; a heat generating body to be cooled through heat exchange with the coolant in a heat generating body flow path; first and second pumps that pump the coolant in the fuel cell and heat generating body flow paths, respectively; and a control circuit. When the vehicle is started, the control circuit performs a first process of actuating the first pump with the second pump stopped, and a second process of actuating the first and second pumps when the temperature of the coolant in the fuel cell or cooling unit flow path exceeds a first reference value during the first process.

A fuel cell system includes a fuel cell stack, a first cooling line having first cooling water that passes via the fuel cell stack and circulates therein, a first radiator that cools the first cooling water, an air conditioning system that forms a heating loop with a first cooling line, a first cooling fan that blows exterior air to the first radiator, a first pump that pumps the first cooling water, a valve that switches a flow path of the first cooling water to the fuel cell stack or the first radiator, and a controller connected to the first cooling fan, the first pump, and the valve, and configured to detect a failure of the valve, control RPMs of the first pump and the first cooling fan to respective maximum levels, and control an RPM of a blower of the air conditioning system to a maximum level.

The invention relates to an energy recovery device for a motor vehicle, having a drive (10) and a fluid circuit (12) for utilising waste heat from the drive (10). A working fluid circulates in the fluid circuit (12). The fluid circuit (12) has a first heat exchanger (16), which is thermally coupled to the drive (10) for transferring waste heat from the drive (10) to the working fluid, an expansion machine (18), and an expansion machine bypass (20), which bypasses the expansion machine (18) and in which a second heat exchanger (22) is arranged.

The present invention relates to a fuel cell device (1) having a fuel cell (2) which, during operation, emits water as a product of cold combustion; a supply air path (3) leading to the fuel cell (2) for a cathode supply air flow (5), which defines a supply air flow direction (4), the cathode supply air flow coming from water-containing supply air supplied to the fuel cell (2); and an exhaust air path (7)leading away from the fuel cell (2), for a cathode exhaust air flow (9), which defines an exhaust air flow direction (8), the cathode exhaust air flow coming from water-containing exhaust air flowing out of the fuel cell (2). The supply air path (3) and the exhaust air path (7) are routed through a humidifier (10) of the fuel cell device (1), which humidifier communicates fluidically with the supply air and the exhaust air, to humidify the supply air and dehumidifying the exhaust air. The exhaust air path (7) is also routed through a water separator (11) of the fuel cell device (1), which water separator communicates fluidically with the exhaust air, for removing water from the exhaust air and for providing this water as evaporation water. The fuel cell device (1) also has a heat exchanger (12) for cooling the fuel cell (2), which heat exchanger has an evaporative cooler (13) for cooling the heat exchanger (12). It is essential that the evaporative cooler (13) is assigned to the water separator (11) in fluidic communication and that it is supplied with evaporation water by same.

A method for preparing a fuel cell system in a vehicle for starting, for which purpose a starting preparation routine is carried out after the vehicle has been shut down depending on a temperature limit value. In the method, in the event that the fuel cell had not reached its normal operating temperature during the previous operation and a temperature falls below the predetermined temperature limit value, the fuel cell system is operated until it has reached its normal operating temperature and after which the starting preparation routine is subsequently carried out.

To provide a fuel cell system configured to achieve both rapid cooling of a fuel cell at high temperatures and rapid heating of the fuel cell at the time of system start-up. In the fuel cell system, by controlling a three-way valve, a controller switches to any one of the following circulation systems: radiator circulation in which a refrigerant flows to a radiator through a first flow path, and third flow path circulation in which the refrigerant bypasses the radiator and flows to a second flow path through a third flow path; when the temperature of the refrigerant is equal to or less than a low temperature threshold, the controller switches from the radiator circulation to the third flow path circulation and closes a first valve; and when the temperature of the refrigerant becomes equal to or more than a high temperature threshold, the controller opens the first valve and circulate the refrigerant to flow through the reserve tank.

A fuel cell system includes a hydrogen tank to store hydrogen, a fuel cell to receive hydrogen gas from the hydrogen tank to generate electricity, a temperature controller to adjust a temperature inside the hydrogen tank, and a control unit to control the temperature controller based on the amount of hydrogen remaining in the hydrogen tank, the control unit being configured to increase the temperature inside the hydrogen tank when the amount of the remaining hydrogen is equal to or less than a first predetermined value.

A cooling system for cooling a fuel cell on a vehicle includes a radiator, a branch portion connected to an outlet side of the radiator, a confluence portion connected to an inlet side of the radiator, a first passage and a second passage connected in parallel between the confluence portion and the branch portion, a fuel cell and a first pump provided in the first passage, a resistor and a second pump provided in the second passage, and a backflow preventer provided in the second passage. The first passage has no backflow preventer.