Abstract: A fuel cell system includes a fuel cell which has an anode. A fuel supplying device circulates a supply of aqueous methanol solution to the anode in the fuel cell. The fuel supplying device includes an aqueous solution tank for storing the aqueous methanol solution. By moving aqueous methanol solution from the aqueous solution tank to a water tank, the amount of aqueous methanol solution which is in circulation at the time of start-up is made smaller than the amount for normal operation. The fuel cell system and a control method therefore are capable of shortening a time that is necessary for heating aqueous fuel solution to be supplied to the fuel cell to a predetermined temperature without reducing fuel utilization efficiency.

Abstract: A fuel cell system and a starting method therefor are capable of setting a start-up mode which is appropriate to energy stored in a secondary battery so as to eliminate problems in starting the fuel cell system. The fuel cell system includes a fuel cell, a secondary battery which is electrically connected with the fuel cell, a secondary-battery charge-amount detection unit which detects an amount of charge in the secondary battery, and a memory which stores at least one threshold value for determining the start-up mode of the fuel cell system. Stored electric energy which corresponds to the amount of charge in the secondary battery is calculated, and a start-up mode of the fuel cell system is determined based on the electric energy stored in the secondary battery and the threshold value stored in the memory.

Abstract: A fuel cell system and a starting method therefore prevent problems when the system is started. The fuel cell system includes a fuel cell, a secondary battery that is electrically connected with the fuel cell, and a cell temperature sensor that detects a temperature of the fuel cell. Energy which is necessary for starting the fuel cell system is calculated based on the temperature of the fuel cell detected by the cell temperature sensor. The calculated value is used as a threshold for determining a start-up mode of the fuel cell system.

Abstract: A fuel cell system including a fuel cell stack is capable of raising the temperature of a fuel cell stack to a predetermined temperature within a short time without decreasing methanol fuel utilization efficiency. During system startup, the concentration of methanol aqueous solution which is to be supplied to the fuel cell stack is detected by a concentration sensor, and the temperature of the fuel cell stack is detected by a temperature sensor. A target concentration of methanol aqueous solution is determined by making reference to data stored in a memory, which indicates correspondence between the temperature of the fuel cell stack and the target concentration of methanol aqueous solution, and based on the temperature of the fuel cell stack detected by the temperature sensor.

Abstract: A fuel cell system that is capable of handling gasified fuel in an aqueous solution tank includes an aqueous solution tank which holds fuel aqueous solution, a fuel cell including an anode supplied with the fuel aqueous solution from the aqueous solution tank, and a cathode provided with a catalyst containing platinum Pt, an air supplying unit including an air pump and arranged to supply air to the cathode in the fuel cell, and a gas guide arranged to add a gas containing gasified methanol from the aqueous solution tank to the air to be sent to the cathode.

Abstract: A fuel cell system and a starting method therefore prevent problems when the system is started. The fuel cell system includes a fuel cell, a secondary battery that is electrically connected with the fuel cell, and a cell temperature sensor that detects a temperature of the fuel cell. Energy which is necessary for starting the fuel cell system is calculated based on the temperature of the fuel cell detected by the cell temperature sensor. The calculated value is used as a threshold for determining a start-up mode of the fuel cell system.

Abstract: A fuel cell system includes a fuel cell which has an anode. A fuel supplying device circulates a supply of aqueous methanol solution to the anode in the fuel cell. The fuel supplying device includes an aqueous solution tank for storing the aqueous methanol solution. By moving aqueous methanol solution from the aqueous solution tank to a water tank, the amount of aqueous methanol solution which is in circulation at the time of start-up is made smaller than the amount for normal operation. The fuel cell system and a control method therefore are capable of shortening a time that is necessary for heating aqueous fuel solution to be supplied to the fuel cell to a predetermined temperature without reducing fuel utilization efficiency.

Abstract: A fuel cell system and a starting method therefor are capable of setting a start-up mode which is appropriate to energy stored in a secondary battery so as to eliminate problems in starting the fuel cell system. The fuel cell system includes a fuel cell, a secondary battery which is electrically connected with the fuel cell, a secondary-battery charge-amount detection unit which detects an amount of charge in the secondary battery, and a memory which stores at least one threshold value for determining the start-up mode of the fuel cell system. Stored electric energy which corresponds to the amount of charge in the secondary battery is calculated, and a start-up mode of the fuel cell system is determined based on the electric energy stored in the secondary battery and the threshold value stored in the memory.

Abstract: A fuel cell system and a control method therefor are capable of improving power generation efficiency of the fuel cell more reliably during a normal operation. A fuel cell system is arranged along a vehicle frame of a motorcycle. The fuel cell system includes a fuel cell having a cathode, an air pump which supplies the cathode with oxygen-containing air, and a CPU which controls operation of elements which constitute the fuel cell system. The CPU determines, depending on situations, whether or not to perform an oxygen-starving process which is a process of starving the cathode of the oxidizer during the normal operation, and stops the air pump when a determination is made to perform the oxygen-starving process.

Abstract: A fuel cell system preferably includes a fuel cell which generates electric energy by electrochemical reaction, an aqueous solution tank which holds the methanol aqueous solution, a water tank which holds fluid discharged from the fuel cell, a fluid level sensor for detecting an amount of fluid in the water tank, a water pump which recycles fluid in the water tank to the aqueous solution tank, and a CPU which controls components of the fuel cell system. After power generation is finished, the water pump is driven to recycle all the fluid in the water tank to the aqueous solution tank. Further, after power generation is finished or before power generation is started, the fluid level sensor detects the amount of fluid in the water tank. If the amount of fluid is not smaller than a predetermined amount, the water pump is driven to recycle fluid in the water tank to the aqueous solution tank. The fuel cell system has a simple construction and is capable of preventing fluid from being discharged outside.

Abstract: A fuel cell system including a fuel cell stack is capable of raising the temperature of a fuel cell stack to a predetermined temperature within a short time without decreasing methanol fuel utilization efficiency. During system startup, the concentration of methanol aqueous solution which is to be supplied to the fuel cell stack is detected by a concentration sensor, and the temperature of the fuel cell stack is detected by a temperature sensor. A target concentration of methanol aqueous solution is determined by making reference to data stored in a memory, which indicates correspondence between the temperature of the fuel cell stack and the target concentration of methanol aqueous solution, and based on the temperature of the fuel cell stack detected by the temperature sensor. The amount of input of methanol fuel is determined based on the concentration of the methanol aqueous solution and the target concentration, and the determined amount of the methanol fuel is inputted to the methanol aqueous solution.

Abstract: A fuel cell system that is capable of handling gasified fuel in an aqueous solution tank includes an aqueous solution tank which holds fuel aqueous solution, a fuel cell including an anode supplied with the fuel aqueous solution from the aqueous solution tank, and a cathode provided with a catalyst containing platinum Pt, an air supplying unit including an air pump and arranged to supply air to the cathode in the fuel cell, and a gas guide arranged to add a gas containing gasified methanol from the aqueous solution tank to the air to be sent to the cathode.