STOPPING METHOD OF PHOSPHORIC ACID TYPE FUEL CELL AND PHOSPHORIC ACID TYPE FUEL CELL

摘要

PROBLEM TO BE SOLVED: To provide a stopping method of a phosphoric acid type fuel cell capable of making phosphoric acid concentration adjustment before the long term storage of the phosphoric acid type fuel cell economical and simple, and a phosphoric acid type fuel cell using it. SOLUTION: For a fuel cell body 1 composed of an air electrode 2, a fuel electrode 3 and a matrix 4, steam generated by a steam separator 6 is supplied from a reformer 7 through a line L3 into a reformed gas during a transition period from a normal generation state to a generation stop state, so that the amount of steam to be supplied to the fuel electrode 3 is increased and the partial pressure of the steam is raised and thereby, the phosphoric acid concentration of the matrix 4 is decreased. By this, the freezing temperature of the phosphoric acid is so lowered that the phosphoric acid is not frozen even if the temperature of the fuel cell is brought down to room temperature.