Patent ID: 8426076

Claim:
A fuel cell comprising: a) a membrane electrode assembly having an anode side and a cathode side; b) a fuel delivery system distributing fuel to the anode side of the membrane electrode assembly; and c) a flow distributor delivering an oxidizer to the cathode side of the membrane electrode assembly and internally humidifying the oxidizer, wherein the flow distributor comprises: (i) a channel wall layer comprising a gas impermeable, water permeable material; (ii) a channel backing layer; (iii) a flow channel that provides, a path for oxidizer delivery to the membrane electrode assembly, wherein the flow channel is defined by the membrane electrode assembly, the channel wall layer and the channel backing layer; (iv) wherein material is gas impermeable when gaseous mass flux through the channel wall is less than 15% of the mass flux through the flow channel; (v) wherein a first portion of the flow channel is internally humidified by transfer of water between the first portion of the flow channel and a second portion of the flow channel through the channel wall layer; and (vi) wherein the second portion of the flow channel is separated from the first portion of the flow channel by a single channel wall layer portion, with no other channel portions or wall layer portions between the first and second flow channel portions.