Patent ID: 8236456

Claim:
A flow shifting fuel cell system comprising: a first fuel cell stack and a second fuel cell stack, each said stack comprising: a plurality of fuel cells, each comprising an anode, a cathode and an electrolyte disposed between said anode and cathode; an anode flowpath fluidly coupled to said anode such that a fluid containing a first reactant can be circulated back and forth across said anode; and a cathode flowpath fluidly coupled to said cathode such that a fluid containing a second reactant can be circulated across said cathode; and a water separator fluidly coupled to said anode flowpath such that at least a portion of water present in said first reactant-containing fluids is removed therefrom, said water separator comprising: a housing defining a separation chamber therein; a bidirectional flowpath configured to allow said respective one of said fluids to be circulated back and forth through said separation chamber; and at least one fluid drain formed in said separation chamber such that condensed water removed from said respective one of said fluids flows to said drain, and wherein said separation chamber comprises a labyrinth separator symmetric about an axis defined by the median between where the flowpath enters and exits the water separator.