Abstract: An electrochemical cell structure has an electrical current-carrying structure which, at least in part, underlies an electrochemical reaction layer. The cell comprises an ion exchange membrane with a catalyst layer on each side thereof. The ion exchange membrane may comprise, for example, a proton exchange membrane. Some embodiments of the invention provide electrochemical cell layers which have a plurality of individual unit cells formed on a sheet of ion exchange membrane material.

Abstract: One aspect of the invention provides an ion-conducting membrane comprising an ion-conducting region and a non-ion-conducting region. The ion-conducting region is formed by a plurality of ion-conducting passageways that extend through the membrane. The passageways are filled with ion-conducting material and may be surrounded by non-ion conducting material. The membrane may comprise a substrate of non-ion-conducting material that is penetrated by openings, each opening providing a corresponding one of the passageways.

Abstract: A freeze tolerant fuel cell power plant (10) includes at least one fuel cell (12), a coolant loop (42) having a porous water transport plate (44) secured in a heat and mass exchange relationship with the fuel cell (12) and a coolant pump (46) for circulating a coolant through the plate (44) and for transferring water into or out of the plate (44) with the coolant. A coolant heat exchanger (52) removes heat from the coolant, and an accumulator (66) stores the coolant and fuel cell product water and directs the product water out of the accumulator (66). The coolant is a two-component mixed coolant liquid circulating through the coolant loop (42) consisting of between 80 and 95 volume percent of a low freezing temperature water immiscible fluid component and between 5 and 20 volume percent of a water component.

Abstract: A freeze tolerant fuel cell power plant (10) includes at least one fuel cell (12), a coolant loop (18) including a freeze tolerant accumulator (22) for storing and separating a water immiscible fluid and water coolant, a direct contact heat exchanger (56) for mixing the water immiscible fluid and the water coolant within a mixing region (72) of the heat exchanger (56), a coolant pump (21) for circulating the coolant through the coolant loop (18), a radiator loop (84) for circulating the water immiscible fluid through the heat exchanger (56), and a radiator (86) for removing heat from the coolant. The plant (10) utilizes the water immiscible fluid during steady-state operation to cool the fuel cell and during shut down of the plant to displace water from the fuel cell (12) to the freeze tolerant accumulator (22).

Abstract: A performance enhancing break-in method for a proton exchange membrane (“PEM”) fuel cell (12) includes cycling potentials of an anode electrode (14) and a cathode electrode (16) from a first potential to a second potential and back to the first potential, and repeating the cycling for each electrode (14, 16) for at least two electrode cycles. The potential cycling may be achieved in a first embodiment by applying a direct current from a programmable direct current power source (80) to the electrodes. Alternatively the potential cycling may be achieved by varying reactants to which the anode and cathode electrodes (14, 16) are exposed.

Abstract: A power plant (10) includes at least one fuel cell (12), a coolant loop (18) including a freeze tolerant accumulator (22) for storing and separating a water immiscible fluid and water coolant, a direct contact heat exchanger (56) for mixing the water immiscible fluid and the water coolant within a mixing region (72) of the heat exchanger (56), a coolant pump (21) for circulating the coolant through the coolant loop (18), a radiator loop (84) for circulating the water immiscible fluid through the heat exchanger (56), a radiator (86) for removing heat from the coolant, and a direct contact heat exchanger by-pass system (200). The plant (10) utilizes the water immiscible fluid during steady-state operation to cool the fuel cell and during shut down of the plant to displace water from the fuel cell (12) to the freeze tolerant accumulator (22).