SYSTEM AND METHOD OF WATER MANAGEMENT IN THE OPERATION OF A FUEL CELL

摘要

A PEM fuel cell system includes a PEM fuel cell (12) that has an input (20, 28, 36) and output port (22, 30, 38) each for fuel or reformate, process air and coolant. A predetermined fraction of volume of moistened exhaust air leaving the air output port (30) of the fuel cell (12) is diverted back and combined with fresh, air at ambient temperature entering the air input port (28) of the PEM fuel cell (12) to maintain water balance in the fuel cell at high ambient operating temperatures. The recycle-to-air vent ratio is controlled by a processor (78) which adjusts the recycle flow (52) based on the ambient temperature and the power level of the fuel cell (12).