TECHNOLOGY FOCUS - ELECTRICAL POWER AND ENERGY - Preferred Components: The gas guide includes a tubular member arranged to guide the gas to a suction side of the air pump of the air supplying unit. The air supplying unit includes an air filter provided at an end of the suction side, and an air chamber provided between the air filter and the air pump and connected with the tubular member. The gas guide further includes a tubular member arranged to guide the gas to a discharge side of the air pump of the air supplying unit. It has a check valve connected with the tubular member and arranged to prevent the gas from flowing back. The air supplying unit includes a pipe, which connects the air pump with the cathode of the fuel cell, the pipe being provided with a throttled portion for reduced cross section of a passage for the gas, and the gas guide is arranged to add the gas to the air at the throttled portion. The fuel cell is operated at greater than or equal to50degreesC. It is a direct methanol fuel cell system or a direct ethanol fuel cell system. It includes direct methanol fuel cells connected in series and each including an electrolyte, the anode, and the cathode. The air supplying unit includes an air-intake pipe, the air pump arranged to pump oxygen-containing air from outside and send the air to the cathode in the fuel cell, an air filter which purifies the air introduced from the outside by the air pump, and an air chamber which reduces noise from the air pump. The air pump includes a pump case and two generally cocoon-shaped rotors housed in the pump case. It has a pipe on its suction side arranged to connect the air pump to the air chamber, and the air-intake pipe connects the air pump to the cathode of the fuel cell. The pipe on the suction side of the air pump has a merging connector fitted to a pipe that connects the air supplying unit with the aqueous solution tank. A pipe is provided between the air chamber and the air filter, and a merger connector is provided on the pipe provided between the air chamber and the air filter, and the merger connector is fitted to a pipe that connects the air supplying unit with the aqueous solution tank.