Method for operating vehicle-mounted fuel cell stack

A method for operating a vehicle-mounted fuel cell stack system, said vehicle-mounted fuel cell stack system comprising:

• (a) a plurality of power generating cells each of which is generally in a shape of a flat plate and includes a solid polymer electrolyte membrane sandwiched between an anode electrode and a cathode electrode, each of said power generating cells generating electric power through reaction, via the solid polymer electrolyte membrane, between fuel gas and reacting air supplied to the anode electrode and cathode electrode, respectively, each of said power generating cells having, in a front end portion thereof that faces forward when said fuel cell stack is mounted on a vehicle, a reacting-air introduction opening for introducing the reacting air into said power generating cell, the reacting-air introduction opening being exposed to an ambient environment;
• (b) one or more cooling cells stacked alternately with said power generating cells, each of said cooling cells including two opposed plates for passage therebetween of cooling air and having, in a front end portion thereof, a cooling-air introduction opening for introducing the cooling air between the opposed plates, the cooling-air introduction opening being exposed to the ambient environment;
• and
• (c) an air allocation mechanism, disposed directly in front of the front end portions of said power generating cells and cooling cells, to allocate air flowing in a front-to-rear direction of the vehicle to the reacting-air introduction openings and to the cooling-air introduction openings as the reacting air and the cooling air, respectively, said air allocation mechanism used to adjust an allocation ratio between the reacting air and the cooling air,
• said method comprising:
• a temperature measurement step of measuring a temperature of said power generating cells;
• and
• a step of, when the temperature measured by said temperature measurement step is lower than a preset standard operating temperature of said power generating cells, performing control to zero an allocated amount of the cooling air via said air allocation mechanism.