Patent ID: 8435693

Claim:
A fuel cell stack, comprising: a membrane-electrode assembly comprising an electrolyte membrane, an anode formed on a first surface of the electrolyte membrane, and a cathode formed on a second surface of the electrolyte membrane; an anode separator comprising a fuel channel, a fuel inlet manifold in fluid communication with the fuel channel, and a fuel outlet manifold in fluid communication with the fuel channel, wherein the anode separator is positioned proximate to the anode; a cathode separator comprising an oxidant channel, an oxidant inlet manifold in fluid communication with the oxidant channel, and an oxidant outlet manifold in fluid communication with the oxidant channel, wherein the cathode separator is positioned proximate to the cathode; and a filling member positioned in at least one of the fuel inlet manifold and the oxidant inlet manifold, the filling member positioned and configured to alleviate pressure and decrease the flow rate of at least one of a fuel and an oxidant, and the filling member formed of a porous member having a pore density of between about 30% and about 70%.