Evaporatively cooled fuel cells with water passageways enhanced by wicks

Abstract

Fuel cells () have passageways () that provide water through one or both reactant gas flow field plates () of each fuel cell, whereby the fuel cell is cooled evaporatively. The water passageways may be vented by a porous plug (not shown), or by a microvacuum pump (). A condenser () may have a reservoir (); the condenser () may be a vehicle radiator. A highly water permeable wicking layer () is disposed adjacent to one or both water passageways () which exist between individual fuel cells (). The passageways may be flow-through passageways () (FIG.) or they may be interdigitated passageways () (FIG.) in order to increase the flow of water-purging air through the wicking layer () utilized to clear the stack of water during shutdown in cold environments. The inlet interdigitated channels () may be only partially blocked at their outlet ends such as by a protrusion () or a hole () in order to ensure that any gas entering the inlet coolant passageways () will not accumulate at the outlet end () of the inlet coolant passageways.