Abstract: A method of manufacturing a flow field plate includes mixing graphite and resin materials to provide a mixture. The mixture is formed into a continuous flow field plate, for example, by ram extrusion or one or more press belts. The continuous flow field plate is separated into discrete flow field plates. Flow field channels are provided in one of the continuous flow field plate and the discrete flow field plates.

Abstract: A composite plate (26) is formed in a mold (8) by placing one of two preforms (15, 23) of between about 80 wt. % and about 85 wt. % flake graphite, balance polymer binder, into the mold and disposing a coolant tube array (18) thereon, depositing a powder (21) of the flake/polymer around the tube array, placing a second preform on the powder and a mold plunger (27) on the second preform, heating the mold to the melting temperature of the polymer under a pressure of 625 psi (4311 kPa), cooling the mold to the solidification temperature of the polymer while still under pressure, cooling the mold further, disassembling the mold, and removing the composite plate. The composite plate has reactant gas flow field channels (31, 32) in major surfaces thereof, is devoid of any acid edge protection layer or film and is devoid of any acid impervious separator plate between either of the fuel cell reactant gas flow fields and the coolant tube array.

Abstract: An illustrative example cell stack assembly includes a plurality of fuel cells that each include a cathode electrode, an anode electrode and a matrix for holding a liquid acid electrolyte. The electrodes have lateral outside edges that are generally coplanar. A plurality of separator plates are respectively between the cathode electrode of one of the fuel cells and the anode electrode of an adjacent one of the fuel cells. The separator plates have lateral outside edges that are generally coplanar with the lateral outside edges of the electrodes. A plurality of barriers along at least one of the lateral outside edges of respective ones of the separator plates extend outwardly beyond the lateral outside edges of the electrodes and separator plates. The barriers inhibit acid migration between one of the electrodes on one side of the barrier and one of the electrodes on an opposite side of the barrier.

Abstract: A stack (10) of fuel cells (11) is manufactured with barriers (32) to prevent migration of a liquid electrolyte (such as phosphoric acid) out of the cells (11). The barrier (32) is secured within a step (34) formed within a land region (28) of a separator plate assembly (18) and extends from an edge (30) of the separator plate assembly (18) all or a portion of a distance between the edge (30) and a flow channel (24) defined within the separator plate assembly (18). The barrier (32) also extends away from the edge (30) a distance of between 0.051 and about 2.0 millimeters (about 2 and about 80 mils. The barrier (32) includes a hydrophobic, polymeric film (36), a pressure sensitive adhesive (38) as an assembly aid, and a fluoroelastomer bonding agent (40).

Abstract: According to an example embodiment, a method of making a fuel cell component includes permeating at least a portion of a component layer with a polymer. The portion of the component layer is adjacent an edge of the component layer. Some of the polymer is allowed to extend beyond the edge to thereby establish a flap beyond the edge of the component layer. A fuel cell component includes a component layer having a portion adjacent an edge of the layer that is impregnated with a polymer material and a flap of the polymer material extending beyond the edge.

Abstract: An illustrative example cell stack assembly includes a plurality of fuel cells that each include a cathode electrode, an anode electrode and a matrix for holding a liquid acid electrolyte. The electrodes have lateral outside edges that are generally coplanar. A plurality of separator plates are respectively between the cathode electrode of one of the fuel cells and the anode electrode of an adjacent one of the fuel cells. The separator plates have lateral outside edges that are generally coplanar with the lateral outside edges of the electrodes. A plurality of barriers along at least one of the lateral outside edges of respective ones of the separator plates extend outwardly beyond the lateral outside edges of the electrodes and separator plates. The barriers inhibit acid migration between one of the electrodes on one side of the barrier and one of the electrodes on an opposite side of the barrier.

Abstract: A stack (10) of fuel cells (11) is provided with barriers (32) to prevent migration of a liquid electrolyte (such as phosphoric acid) out of the cells (11). The barrier (32) is secured within a step (34) defined within a land region (28) of a separator plate assembly (18) and extends from an edge (30) of the separator plate assembly (18) all or a portion of a distance between the edge (30) and a flow channel (24) defined within the separator plate assembly (18). The barrier (32) also extends away from the edge (30) a distance of between 0.051 and 2.0 millimeters (2 and 80 mils). The barrier (32) includes a hydrophobic, polymeric film (36), a pressure sensitive adhesive (38), as an assembly aid, and a fluoroelastomer bonding agent (40).

Abstract: An end-cooler assembly for a fuel cell includes a cooler having a coolant tube array. A composite material includes flake graphite and hydrophobic polymer. The composite material surrounds the coolant tube array and provides a first side. A flow field is formed in the first side. A thermal dam is embedded in and is entirely surrounded by the composite material. The thermal dam is arranged between the coolant tube array and the flow field. The coolant tube array, composite material, flow field and thermal dam comprise a unitary, monolithic structure bound together by the composite material.

Abstract: According to an example embodiment, a method of making a fuel cell component includes permeating at least a portion of a component layer with a polymer. The portion of the component layer is adjacent an edge of the component layer. Some of the polymer is allowed to extend beyond the edge to thereby establish a flap beyond the edge of the component layer. A fuel cell component includes a component layer having a portion adjacent an edge of the layer that is impregnated with a polymer material and a flap of the polymer material extending beyond the edge.

Abstract: The oxidant inlets of the reactant gas flow field grooves (41) of a fuel cell (11) which suffers a crossover between the fuel and oxidant flow fields, due to a leak in the seals, the maxtrix or the membrane of the fuel cell, are blocked with a liquid (50) which cures in place, hot glue, two-part epoxy, or fluoroelastomers. This prevents heating as a result of combusting fuel with oxygen near the site, which avoids excessive heating and damaging of successive fuel cells. As a result, a fuel cell power plant (8) can continue to operate with only a minor loss of voltage and power, thereby avoiding the need to tear down the stack by loosening the tie-bolts. Voltage and hydrogen levels may be used to detect the crossover. The particular cell (11) with the leak can be determined by voltage or hydrogen monitoring, or by immersing the stack in a liquid while applying gas to the fuel inlet of the stack.

Abstract: A method of manufacturing a flow field plate includes mixing graphite and resin materials to provide a mixture. The mixture is formed into a continuous flow field plate, for example, by ram extrusion or one or more press belts. The continuous flow field plate is separated into discrete flow field plates. Flow field channels are provided in one of the continuous flow field plate and the discrete flow field plates.

Abstract: A composite plate (26) is formed in a mold (8) by placing one of two preforms (15, 23) of between about 80 wt.% and about 85 wt.% flake graphite, balance polymer binder, into the mold and disposing a coolant tube array (18) thereon, depositing a powder (21) of the flake/polymer around the tube array, placing a second preform on the powder and a mold plunger (27) on the second preform, heating the mold to the melting temperature of the polymer under a pressure of 625 psi (4311 kPa), cooling the mold to the solidification temperature of the polymer while still under pressure, cooling the mold further, disassembling the mold, and removing the composite plate. The composite plate has reactant gas flow field channels (31, 32) in major surfaces thereof, is devoid of any acid edge protection layer or film and is devoid of any acid impervious separator plate between either of the fuel cell reactant gas flow fields and the coolant tube array.

Abstract: An end-cooler assembly for a fuel cell includes a cooler having a coolant tube array. A composite material includes flake graphite and hydrophobic polymer. The composite material surrounds the coolant tube array and provides a first side. A flow field is formed in the first side. A thermal dam is embedded in and is entirely surrounded by the composite material. The thermal dam is arranged between the coolant tube array and the flow field. The coolant tube array, composite material, flow field and thermal dam comprise a unitary, monolithic structure bound together by the composite material.

Abstract: A stack (10) of fuel cells (11) is provided with barriers (32) to prevent migration of a liquid electrolyte (such as phosphoric acid) out of the cells (11). The barrier (32) is secured within a step (34) defined within a land region (28) of a separator plate assembly (18) and extends from an edge (30) of the separator plate assembly (18) all or a portion of a distance between the edge (30) and a flow channel (24) defined within the separator plate assembly (18). The barrier (32) also extends away from the edge (30) a distance of between 0.051 and 2.0 millimeters (2 and 80 mils). The barrier (32) includes a hydrophobic, polymeric film (36), a pressure sensitive adhesive (38), as an assembly aid, and a fluoroelastomer bonding agent (40).

Abstract: A stack (10) of fuel cells (11) is manufactured with barriers (32) to prevent migration of a liquid electrolyte (such as phosphoric acid) out of the cells (11). The barrier (32) is secured within a step (34) formed within a land region (28) of a separator plate assembly (18) and extends from an edge (30) of the separator plate assembly (18) all or a portion of a distance between the edge (30) and a flow channel (24) defined within the separator plate assembly (18). The barrier (32) also extends away from the edge (30) a distance of between 0.051 and about 2.0 millimeters (about 2 and about 80 mils. The barrier (32) includes a hydrophobic, polymeric film (36), a pressure sensitive adhesive (38) as an assembly aid, and a fluoroelastomer bonding agent (40).

Abstract: A fuel cell separator plate assembly (20, 20a) includes a separator layer (22, 22a) and one or more reactant flow field layers (24, 24a, 26, 26a) comprising graphite flakes and a thermoplastic, hydrophobic resin which secures flow field layers on opposite sides of the separator layer. In another example, a separator plate assembly (20a) comprises a monolithic structure in which the separator portion (22a) and the flow field portions (24a, 26a) are all formed in a single piece of the same material. A method heats thermoplastic resin to its point of complete melting, then cools to its point where melting begins, increasing both electric and thermal conductivity. Methods include bonding under higher pressure than previously used, about 800 psi, or under pressures about 750 psi.

Abstract: The oxidant inlets of the reactant gas flow field grooves (41) of a fuel cell (11) which suffers a crossover between the fuel and oxidant flow fields, due to a leak in the seals, the maxtrix or the membrane of the fuel cell, are blocked with a liquid (50) which cures in place, hot glue, two-part epoxy, or fluoroelastomers. This prevents heating as a result of combusting fuel with oxygen near the site, which avoids excessive heating and damaging of successive fuel cells. As a result, a fuel cell power plant (8) can continue to operate with only a minor loss of voltage and power, thereby avoiding the need to tear down the stack by loosening the tie-bolts. Voltage and hydrogen levels may be used to detect the crossover. The particular cell (11) with the leak can be determined by voltage or hydrogen monitoring, or by immersing the stack in a liquid while applying gas to the fuel inlet of the stack.