Abstract: A separator for a fuel cell includes protrusions spaced apart from each other. The protrusions are configured to contact a power generation portion. The separator includes a gas passage that extends between two adjacent ones of the protrusions. The gas passage includes ribs that protrude toward the power generation portion. The ribs include first ribs spaced apart from each other in an arrangement direction of the protrusions and a second rib located between adjacent ones of the first ribs in the arrangement direction. A downstream end of each of the first ribs includes a separated portion separated from the power generation portion. An upstream end of the second rib includes an inclined portion inclined so as to become closer to the power generation portion toward a downstream side. At least part of the inclined portion is located downstream of at least part of the separated portion.

Abstract: A separator for a fuel cell includes protrusions that extend in parallel and are spaced apart from each other. The protrusions are configured to contact a power generation portion. The separator includes a gas passage that extends between two adjacent ones of the protrusions along the protrusions. The gas passage is configured to allow reactant gas to flow through the gas passage. The gas passage includes at least one rib that protrudes toward the power generation portion and extends in an extending direction of the gas passage. A downstream end of the rib includes a gradually-changing portion that gradually becomes farther from the power generation portion toward a downstream side.

Abstract: A separator for a fuel cell includes protrusions and gas passage portions. The protrusions each include a contact surface configured to contact a power generation portion. The gas passage portions are each arranged between two adjacent ones of the protrusions. An upstream side and a downstream side are defined with reference to a direction in which reactant gas flows through the gas passage portions. The protrusions each include a downstream end. The contact surfaces of the protrusions each include a first groove extending along an extending direction of the protrusions. The downstream end of each of the protrusions includes a separation surface. The separation surface is continuous with the contact surface on the downstream side and separated from the power generation portion. The separation surface includes a second groove that is continuous with the first groove.

Abstract: A fuel cell stack includes stacked cells, each including a sheet-shaped power generation portion, two separators, a gas passage defining plate that includes a gas passage portion through which reactant gas flows, and a frame member that includes a supply port and a discharge port. The gas passage portion includes opposing portions extended in a flow direction of the reactant gas and arranged in parallel in an orthogonal direction. A main passage is defined between each opposing portion and the power generation portion. The gas passage portion includes a first passage portion adjacent to the supply port in the flow direction and a second passage portion adjacent to the first passage portion in the orthogonal direction. The main passages of the second passage portion each have a larger cross-sectional flow area than the main passages of the first passage portion.

Abstract: A fuel cell stack includes stacked cells, each including a sheet-shaped power generation portion, two separators, a gas passage defining plate that includes a gas passage portion through which reactant gas flows, and a frame member that includes a supply port and a discharge port. The gas passage portion includes opposing portions extended in a flow direction of the reactant gas and arranged in parallel in an orthogonal direction and wavy portions each having a wavy cross- sectional shape orthogonal to the orthogonal direction. The gas passage portion includes a first passage portion adjacent to the supply port in the flow direction and a second passage portion adjacent to the first passage portion in the orthogonal direction. The connection passages of the second passage portion each have a larger cross-sectional flow area than the connection passages of the first passage portion.

Abstract: A gas flow passage formation plate includes a plurality of projections arranged in a first direction and a second direction. The projections project toward a membrane electrode assembly. The gas flow passage formation plate further includes a gas flow passage, a water flow passage, and a plurality of openings. The gas flow passage is formed by a portion of the gas flow passage formation plate at a side opposing the membrane electrode assembly including regions between two adjacent projections. The water flow passage is formed by a portion of the gas flow passage formation plate at a side opposing a partition plate including the inside of the projections. The openings are each formed in a side wall of the projection connecting inside and outside of the projection. Each opening is arranged at only one location in one projection.

Abstract: A fuel battery includes unit cells, each of which includes a membrane electrode assembly having two gas diffusion layers. Gas passage forming bodies are stacked on an outer surface of each of the gas diffusion layers of each of the unit cells so that each of the unit cells includes a fuel gas passage and an oxidant gas passage. Each of the gas passage forming bodies includes water guide passages, each of which is located between adjacent ones of the gas passages. A communication passage is arranged between each of the gas passages and an adjacent one of the water guide passages to guide water from the gas passage to the water guide passage. The communication passage has a higher pressure loss than that of the gas passage.

Abstract: A fuel cell includes a first separator and a second separator. A second protrusion is formed on a first sealing portion of the first separator. A concave portion is formed in a second sealing portion of the second separator. When fuel cells are stacked together sequentially in the vertical direction without displacing relative to one another, the center of the second protrusion and the center of the concave portion are aligned with each other. Even if the fuel cells are displaced while being stacked together, the upper fuel cell in the vertical direction is moved to decrease the distance between the center of the second protrusion and the center of the corresponding concave portion.

Abstract: A channel forming body used in a fuel cell module has a gas channel, a water conduit, and a communication path that provides communication between the gas channel and the water conduit. When a ridge is seen in a cross-section perpendicular to a channel extension direction, one of both ends of an external shape of the ridge is shaped so as to be located closer to a center of the ridge than an imaginary surface of the channel assumed to extend in a straight line along the channel extension direction. Portions of the ridge located closer to the center of the ridge are formed opposite from each other at left and right ends of the external shape of the ridge with the communication path interposed therebetween.

Abstract: A gas channel forming plate is arranged between a membrane electrode assembly and a flat separator base. The gas channel forming plate includes gas channels arranged on a surface that faces the membrane electrode assembly, water channels each formed on the back side of the protrusion between an adjacent pair of the gas channels, communication passages that connect the gas channels and the water channels to each other, and guide portions formed by causing an inner wall surface of a gas channel to protrude inward in the gas channel. The guide portions are formed such that the upstream edge of each communication passage is arranged in a range in which, in the velocity vector of the gas flowing in the gas channel, the directional component directed from the side corresponding to the membrane electrode assembly toward the flat separator base has a positive value.

Abstract: A gas passage forming body for a fuel battery includes gas passages and water guide passages. A communication passage is arranged between one of the water guide passages and a gas passage that is adjacent to the water guide passage and is in communication with the adjacent gas passage and water guide passage to permit water to move therethrough. An aid portion is arranged at water drainage ends of two adjacent ones of the water guide passages and aids bonding of water drained from the water drainage ends of the two adjacent ones of the water guide passages. Thus, water drainage from the water guide passages of the gas passage forming body is improved, and water in the gas passages is reduced. As a result, the battery performance of the fuel battery is improved due to an improvement in gas diffusion.

Abstract: A gas flow passage formation plate includes projections arranged in a first direction and a second direction orthogonal to the first direction. The gas flow passage formation plate includes a gas flow passage formed by a portion of the gas flow passage formation plate at a side opposing a membrane electrode assembly including regions between adjacent projections, a water flow passage formed by a portion of the gas flow passage formation plate at a side opposing a partition plate including inside of the projections, and openings each formed in a side wall of the projection connecting inside and outside of the projection. In a state in which the openings sandwich the gas flow passage, the openings are arranged so as not to oppose and overlap each other in a direction orthogonal to a direction in which gas flows.

Abstract: A gas flow passage formation plate includes a plurality of projections arranged in a first direction and a second direction. The projections project toward a membrane electrode assembly. The gas flow passage formation plate further includes a gas flow passage, a water flow passage, and a plurality of openings. The gas flow passage is formed by a portion of the gas flow passage formation plate at a side opposing the membrane electrode assembly including regions between two adjacent projections. The water flow passage is formed by a portion of the gas flow passage formation plate at a side opposing a partition plate including the inside of the projections. The openings are each formed in a side wall of the projection connecting inside and outside of the projection. Each opening is arranged at only one location in one projection.

Abstract: A gas flow passage-forming member is disposed between a membrane electrode and gas diffusion layer assembly and a separator of a fuel cell, and the gas flow passage-forming member is configured to form a gas flow passage. The gas flow passage-forming member has a corrugated shape such that groove portions and ridge portions are provided on each of a front side and a back side of the gas flow passage-forming member. The groove portions each serve as the gas flow passage. The gas flow passage-forming member has communication holes providing communication between the front side and the back side, and the communication holes are provided in a region downstream of an upstream region in a gas flow direction. The upstream region is a non-communication region with no communication hole.

Abstract: A gas channel forming plate includes protrusions, which extend parallel with each other, gas channels that are respectively located between each adjacent pair of the protrusions, and water channels, which are respectively formed on the back surface of each protrusion. Each protrusion includes first communication portions and second communication portions. Each first communication portion includes a first opening. Each second communication portion includes a second opening. The second communication portions of each protrusion constitute an expanding region, in which the opening area of the second opening in each second communication portion is greater than the opening area of the first opening of each first communication portion, to limit introduction of water to the water channel on the back side of the protrusion using capillary action by the second communication portions.

Abstract: A gas channel forming member is located between a separator and a membrane electrode assembly. The gas channel forming member includes gas channels, which are arranged in parallel with each other on a surface that faces the membrane electrode assembly, water channels, which are formed on a surface that faces the separator, and inner communication passages. The water channels are each located between adjacent two of the gas channels. The inner communication passages communicate the gas channels and the water channels with each other. Each water channel is formed such that the flow cross-sectional area in an outlet section including an outlet opening is larger than the cross-sectional area of an upstream section, which is upstream of an adjacent to the outlet section in the flow direction of the oxidant gas.

Abstract: Gas flow channels are provided between protrusions arranged in parallel on a first surface of a partition wall of a gas flow channel forming body, and water introduction channels are provided in valleys on the opposite side of each protrusion, on a second surface. In order to allow the gas flow channels and the water introduction channels to communicate so that water can pass there through, communication channels is provided to the partition wall. Intermediate structures are correspondingly provided inside the water introduction channels to the communication channels. A set of communication channels is formed by a pair of communication channels positioned at a first interval. A set of communication channels and another set of communication channels adjacent thereto are positioned on each protrusion with a second interval therebetween.

Abstract: A gas flow passage-forming member is disposed between a membrane electrode and gas diffusion layer assembly and a separator of a fuel cell, and the gas flow passage-forming member is configured to form a gas flow passage. The gas flow passage-forming member has a corrugated shape such that groove portions and ridge portions are provided on each of a front side and a back side of the gas flow passage-forming member. The groove portions each serve as the gas flow passage. The gas flow passage-forming member has communication holes providing communication between the front side and the back side, and the communication holes are provided in a region downstream of an upstream region in a gas flow direction. The upstream region is a non-communication region with no communication hole.

Abstract: A cathode-side gas flow path of a cell that forms part of a fuel cell is formed by a first expanded metal arranged on a gas inlet side, and a second expanded metal arranged on a downstream side. The first expanded metal is such that mesh is arranged in a straight line, and gas that flows on a gas diffusion layer side is separated from gas that flows on a separator side. The gas flowrate on the gas inlet side is reduced, so the amount of produced water that is carried away is reduced. As a result, the gas inlet side is inhibited from becoming dry at high temperatures.

Abstract: A channel forming body used in a fuel cell module has a gas channel, a water conduit, and a communication path that provides communication between the gas channel and the water conduit. When a ridge is seen in a cross-section perpendicular to a channel extension direction, one of both ends of an external shape of the ridge is shaped so as to be located closer to a center of the ridge than an imaginary surface of the channel assumed to extend in a straight line along the channel extension direction. Portions of the ridge located closer to the center of the ridge are formed opposite from each other at left and right ends of the external shape of the ridge with the communication path interposed therebetween.