Fuel cell system and control method thereof

21:

• The fuel cell system according to claim 20, wherein the fuel supplying device includes an aqueous solution tank arranged to store the aqueous fuel solution, and the aqueous solution amount adjusting device adjusts an amount of the aqueous fuel solution in the aqueous solution tank.

22:

• The fuel cell system according to claim 21, further comprising a tank, separate from the aqueous solution tank, arranged to store the aqueous fuel solution;
• wherein the aqueous solution amount adjusting device is arranged to move the aqueous fuel solution from the aqueous solution tank to the separate tank.

23:

• The fuel cell system according to claim 20, further comprising a water tank arranged to store liquid discharged from the fuel cell, wherein the aqueous solution amount adjusting device is arranged to move the aqueous fuel solution from the fuel supplying device to the water tank.

24:

• The fuel cell system according to claim 20, further comprising a relief tank arranged to receive the aqueous fuel solution from the fuel supplying device, wherein the aqueous solution amount adjusting device is arranged to move the aqueous fuel solution from the fuel supplying device to the relief tank.

25:

• The fuel cell system according to claim 20, further comprising a temperature detecting device arranged to detect a temperature of the fuel cell, wherein the aqueous solution amount adjusting device adjusts the amount of the aqueous fuel solution in the fuel supplying device in accordance with the temperature of the fuel cell detected by the temperature detecting device.

26:

• The fuel cell system according to claim 20, further comprising a secondary battery electrically connected with the fuel cell, and a charge detection device arranged to detect an amount of a charge in the secondary battery, wherein the aqueous solution amount adjusting device adjusts the amount of the aqueous fuel solution in the fuel supplying device in accordance with the amount of the charge detected by the charge detecting device.

27:

• The fuel cell system according to claim 20, wherein the aqueous solution amount adjusting device increases the amount of the aqueous fuel solution in the fuel supplying device to a predetermined amount for the normal operation after the start-up operation.

28:

• The fuel cell system according to claim 27, further comprising a temperature detecting device arranged to detect a temperature of the fuel cell, wherein the aqueous solution amount adjusting device increases the amount of the aqueous fuel solution in the fuel supplying device in accordance with the temperature of the fuel cell detected by the temperature detecting device.

29:

• The fuel cell system according to claim 27, further comprising a temperature detecting device arranged to detect a temperature of the fuel cell, wherein the aqueous solution amount adjusting device increases the amount of the aqueous fuel solution in the fuel supplying device when the temperature of the fuel cell detected by the temperature detecting device has reached a predetermined temperature, so that the temperature of the fuel cell will stay at the predetermined temperature.

30:

• The fuel cell system according to claim 27, further comprising a temperature detecting device arranged to detect a temperature of the fuel cell, wherein the aqueous solution amount adjusting device increases the amount of the aqueous fuel solution in the fuel supplying device to the predetermined amount when the temperature of the fuel cell detected by the temperature detecting device has reached a predetermined temperature.

31:

• Transportation equipment including the fuel cell system according to claim 20.

32:

• A method of controlling a fuel cell system, which includes a fuel cell having an anode and a fuel supplying device arranged to supply an aqueous fuel solution to the anode of the fuel cell, the method comprising:
• a step of setting an amount of the aqueous fuel solution in the fuel supplying device for a start-up to an amount smaller than an amount for a normal operation.

33:

• The method according to claim 32, further comprising adjusting the amount of the aqueous fuel solution in the fuel supplying device based on a temperature of the fuel cell.

34:

• The method according to claim 32, wherein the fuel cell system includes a secondary battery electrically connected with the fuel cell, and the method further comprises the step of adjusting the amount of the aqueous fuel solution in the fuel supplying device based on an amount of a charge in the secondary battery.

35:

• The method according to claim 32, further comprising increasing the amount of the aqueous fuel solution in the fuel supplying device to a predetermined amount for the normal operation after the start-up operation.

36:

• The method according to claim 35, wherein the amount of the aqueous fuel solution in the fuel supplying device is increased in accordance with a temperature of the fuel cell.

37:

• The method according to claim 35, wherein the amount of the aqueous fuel solution in the fuel supplying device is increased when a temperature of the fuel cell has reached a predetermined temperature such that the temperature of the fuel cell will stay at the predetermined temperature.

38:

• The method according to claim 35, wherein the amount of the aqueous fuel solution in the fuel supplying device is increased to the predetermined amount when a temperature of the fuel cell has reached a predetermined temperature.