Fuel cell shut-down procedure including vaporization phase

摘要

A shut-down procedure for an electricity delivery system comprising a fuel cell, the cell being fed with pure oxygen as oxidant and delivering an electrical voltage to an electrical power line. The electricity delivery system comprises a fuel gas circuit on the anode side, and a pure oxygen circuit on the cathode side. The shut-down procedure comprises the steps of an initial step during which the oxygen gas feed is interrupted, and an electrical consumption phase during which a hold current is drawn from the fuel cell until the pressure in the oxygen circuit reaches the water vapor pressure.

主权项

1. A shut-down procedure for an electricity delivery system comprising a fuel cell, the fuel cell being fed with pure oxygen as oxidant from a pure oxygen circuit on the cathode side and hydrogen from a fuel gas circuit on the anode side and delivering an electrical voltage to an electrical power line, the shut-down procedure comprising:
an initial step during which the oxygen gas feed is interrupted; an electrical consumption phase during which a hold current is drawn from the fuel cell until the pressure in the oxygen circuit is reduced to the vapor pressure of water at the temperature of the fuel cell; and a vaporization phase during which water present in channels of the fuel cell is vaporized by pressure reduction produced in the electrical consumption phase.