| 摘要 |
A fuel cell power plant comprises a water circulation passage ( 5 ) which circulates the cooling water in a fuel cell stack ( 4 ). Sodium hydroxide which lowers the melting point of water is mixed with water in the water circulation passage ( 5 ) to prevent freezing of the water in the water circulation passage ( 5 ). Electrodes ( 11, 12 ) are disposed in the water. When the fuel cell stack ( 4 ) is running, a voltage is applied between the electrodes ( 11, 12 ) such that the positive electrode ( 11 ) attracts sodium ions, thereby removing sodium ions from the cooling water supplied to the fuel cell stack ( 4 ). When the fuel cell stack ( 4 ) stops running, sodium ions which were attracted to the positive electrode ( 11 ) are made to diffuse into the cooling water by ceasing to apply the voltage to the electrodes ( 11, 12 ). |
