Bidirectional water separator

A flow shifting fuel cell system comprising:

• at least one fuel cell stack comprising a plurality of individual fuel cells, each of said individual fuel cells comprising an anode, a cathode and a membrane disposed between said anode and cathode;
• a cathode flowpath configured to couple said cathodes of said individual fuel cells within said stack to a source of an oxygen-bearing fluid;
• an anode flowpath configured to couple said anodes of said individual fuel cells within said stack to a source of fuel-bearing fluid, said anode flowpath configured such that fuel present within said anode flowpath cycles back and forth therethrough;
• at least one flow manipulation device fluidly coupled to said anode flowpath and configured to regulate said flow of said fuel-bearing fluid therethrough;
• and
• a water separator in fluid communication with said anode flowpath, said water separator configured to separate water from said fuel-bearing fluid while said fuel-bearing fluid cycles back and forth within said anode flowpath.

A method of operating a fuel cell system, said method comprising:

• configuring said system such that a fuel-bearing fluid is capable of cycling back and forth through an anode flowpath between a plurality of ports that define alternating inlet and outlet ports of at least one fuel cell stack;
• cycling said fuel-bearing fluid through an anode flowpath;
• flowing an oxygen-bearing fluid through a cathode flowpath;
• reacting at least a portion of said fuel-bearing fluid and at least a portion of said oxygen-bearing fluid such that water is produced;
• and
• separating water that accumulates in said anode flowpath while said cycling back and forth occurs.