A fuel cell anode flow field includes at least one flow channel with a cross-sectional area that varies along at least a portion of its length. In some embodiments, the channel width decreases along at least a portion of the channel length according to a natural exponential function. This type of anode flow field can improve performance, reduce fuel consumption and/or reduce detrimental effects such as carbon corrosion and catalyst degradation, thereby improving fuel cell longevity and durability. When operating the fuel cell on either a substantially pure or a dilute fuel stream, this type of anode flow field can provide more uniform current density. These flow channels can be incorporated into reactant flow field plates, fuel cells and fuel cell stacks.

A fuel cell anode flow field includes at least one flow channel with a cross-sectional area that varies along at least a portion of its length. In some embodiments, the channel width decreases along at least a portion of the channel length according to a natural exponential function. This type of anode flow field can improve performance, reduce fuel consumption and/or reduce detrimental effects such as carbon corrosion and catalyst degradation, thereby improving fuel cell longevity and durability. When operating the fuel cell on either a substantially pure or a dilute fuel stream, this type of anode flow field can provide more uniform current density. These flow channels can be incorporated into reactant flow field plates, fuel cells and fuel cell stacks.

A fuel cell anode flow field includes at least one flow channel with a cross-sectional area that varies along at least a portion of its length. In some embodiments, the channel width decreases along at least a portion of the channel length according to a natural exponential function. This type of anode flow field can improve performance, reduce fuel consumption and/or reduce detrimental effects such as carbon corrosion and catalyst degradation, thereby improving fuel cell longevity and durability. When operating the fuel cell on either a substantially pure or a dilute fuel stream, this type of anode flow field can provide more uniform current density. These flow channels can be incorporated into reactant flow field plates, fuel cells and fuel cell stacks.

A fuel cell anode flow field includes at least one flow channel with a cross-sectional area that varies along at least a portion of its length. In some embodiments, the channel width decreases along at least a portion of the channel length according to a natural exponential function. This type of anode flow field can improve performance, reduce fuel consumption and/or reduce detrimental effects such as carbon corrosion and catalyst degradation, thereby improving fuel cell longevity and durability. When operating the fuel cell on either a substantially pure or a dilute fuel stream, this type of anode flow field can provide more uniform current density. These flow channels can be incorporated into reactant flow field plates, fuel cells and fuel cell stacks.

A separator for a fuel cell includes a facing surface configured to face a power generating unit of the fuel cell. Groove passages are arranged side by side in the facing surface. Reactant gas flows through the groove passages. Ribs, which are located between the groove passages and protrude toward the power generating unit, are provided on the facing surface. At least one of the ribs includes at least one protrusion that protrudes toward the power generating unit.

A fuel cell separator includes ribs. The fuel cell separator has a plurality of gas flow paths separated from each other by the ribs. The fuel cell separator has, on a surface of the ribs on the gas flow path side, a liquid water flow path provided separately from the gas flow paths along the gas flow paths. The liquid water flow path has an expanded region in which a cross-sectional area of the liquid water flow path in a direction perpendicular to a flow direction of the liquid water flow path is larger than a cross-sectional area of the liquid water flow path in the direction perpendicular to the flow direction in a remaining region of the liquid water flow path.

The invention relates to a fuel cell system assembly comprising at least two coupled fuel cell systems (A, B) that can be operated at different load points, each fuel cell system (A, B) being connected to a respective cooling circuit (3A, 3B) comprising a circulating coolant, via a coolant supply line (1A, 1B) and a coolant drain line (2A, 2B). According to the invention, the cooling circuits (3A, 3B) are coupled via a common return line (4), via which the coolant supply lines (1A, 1B) can be supplied with coolant, and a return conduit of at least one ancillary unit (5, 6), for example an electric heating device (5) and/or a heater core (6), is connected to the common return line (4).

The invention relates to a fuel cell system assembly comprising at least two coupled fuel cell systems (A, B) that can be operated at different load points, each fuel cell system (A, B) being connected to a respective cooling circuit (3A, 3B) comprising a circulating coolant, via a coolant supply line (1A, 1B) and a coolant drain line (2A, 2B). According to the invention, the cooling circuits (3A, 3B) are coupled via a common return line (4), via which the coolant supply lines (1A, 1B) can be supplied with coolant, and a return conduit of at least one ancillary unit (5, 6), for example an electric heating device (5) and/or a heater core (6), is connected to the common return line (4).

A fuel cell interconnect includes fuel ribs disposed on a first side of the interconnect and a least partially defining fuel channels, and air ribs disposed on an opposing second side of the interconnect and at least partially defining air channels. The fuel channels include central fuel channels disposed in a central fuel field and peripheral fuel channels disposed in peripheral fuel fields disposed on opposing sides of the central fuel field. The air channels include central air channels disposed in a central air field and peripheral air channels disposed in peripheral air fields disposed on opposing sides of the central air field. At least one of the central fuel channels or the central air channels has at least one of a different cross-sectional area or length than at least one of the respective peripheral fuel channels or the respective peripheral air channels.

A load receiver member of a fuel cell separator member of a fuel cell stack includes an attachment portion disposed between an outer peripheral portion of a first metal separator and an outer peripheral portion of a second metal separator, and a tab continuous with the attachment portion and protruding from an outer peripheral portion of a joint separator. The attachment portion is joined to the outer peripheral portion of the joint separator by a joint portion.