Abstract: The cathode recirculation system for a fuel cell module may include an inert gas inlet passage configured to receive inert gas and an oxygen gas inlet passage configured to receive oxygen, a blending component in fluid communication with the inert gas inlet passage, the oxygen gas inlet passage, and an inlet of at least one cathode, and a recirculation line in fluid communication with an outlet of the at least one cathode and the blending component configured to recirculate a mixed gas stream containing oxygen and an inert gas. At least a portion of the mixed gas released from the at least one cathode may be recirculated back to the blending component where oxygen, inert gas, or both oxygen and inert gas are introduced into the recirculated mixed gas stream and then supplied to the inlet of the at least one cathode.

Abstract: The invention describes a new design of ionomer membrane fuel cell stack comprising a multiplicity of stainless steel bipolar plates, electrodes, membranes and perimetrical sealing gaskets enclosed between compression plates. The novel design is directed to prevent the build up of metal ions in the membranes and the consequent voltage decay; for this purpose, the lateral migration inside the ionomer membranes of the metal ions contained in the cooling fluid is prevented.

Abstract: An improved design of gas fed polymeric membrane fuel cell stack is herein described. The stack is provided with a humidifying device which takes advantage of the atomization of a water stream over a high specific surface metallic material, and with a cooling circuit withdrawing the heat generated therein by thermal exchange on a peripheral region, external to the single cell active area. The device is particularly suited for high temperature and high current density operation.

Abstract: A humidification device for polymeric membrane fuel cell stacks fed with gaseous reactants is disclosed. The gases supplied to the stack are previously fed in admixture with a stream of liquid water to a chamber filled with a reticulated material, whose highly subdivided geometry provides an extended exchange surface favouring the saturation of gas. The device is more efficient and compact than those known in the art.

Abstract: An improved design of gas fed polymeric membrane fuel cell stack is herein described. The stack is provided with a humidifying device which takes advantage of the atomisation of a water stream over a high specific surface metallic material, and with a cooling circuit withdrawing the heat generated therein by thermal exchange on a peripheral region, external to the single cell active area. The device is particularly suited for high temperature and high current density operation.