Patent ID: 6841278
Filing Date: 2005-01-11
Classification: H01M,Y02E

Abstract:
1. A method of regenerating the performance of a PEM fuel cell slack in which each cell has an anode flow field to which a hydrogen rich gas is continuously supplied, and has a cathode flow field to which oxidant reactant gas is provided by a pump, said fuel cell stack having a normal load, said method being performed after performance of the fuel cell stack has decayed as a consequence of operation for a period of time between several tens of hours and thousands of hours, said method comprising: (a) disconnecting the normal load from said fuel cell stack and connecting in its place an auxiliary load for drawing a predetermined amount of current from said fuel cell stack; and (b) while said auxiliary load is connected to said fuel cell stack, repetitively, for a predetermined number of repetitions, totally interrupting the flow of oxidant reactant gas to the cathodes of all said fuel cells in said stack simultaneously for a period of time sufficient to reduce the cell voltage to less than 0.1 volts.