JP4910461B2 - Fluid introduction member for fuel cell stack and fuel cell stack - Google Patents

Description

  The present invention relates to a manifold constituting surface that constitutes a part of a fluid supply manifold that supplies a fluid that is gas or refrigerant to the inside of a fuel cell stack, and fluid introduction that guides the fluid flowing along the manifold constituting surface in a different direction. TECHNICAL FIELD The present invention relates to a fuel cell stack fluid introduction member having a shape including a surface and an improvement of a fuel cell stack having the fluid introduction member.

  The fuel cell stack is configured by stacking a plurality of sets of fuel cell units, for example, a membrane-electrode assembly (MEA) composed of an anode side electrode, an electrolyte membrane and a cathode side electrode and a separator. That is, each fuel cell is configured by arranging an anode side electrode on one side of an electrolyte membrane made of a polymer ion exchange membrane, a cathode side electrode on the other side, and further providing separators on both sides. is doing. A plurality of such fuel battery cells are stacked and sandwiched between current collector plates, insulating plates, and end plates to constitute a fuel cell stack that generates a high voltage.

  In the fuel cell stack described in Patent Document 1, as shown in FIG. 10, each fuel cell 10 is divided into a membrane-electrode assembly 12, an anode side reaction gas diffusion layer 14 provided on both sides, and a cathode side. Reaction gas diffusion layer 16, anode-side metal plate 18 and anode-side resin frame 20 provided on one side of membrane-electrode assembly 12 (upper side in FIG. 10), and other side of membrane-electrode assembly 12 (lower side in FIG. 10) ) Provided on the cathode side resin frame 22 and the cathode side metal plate 24. The anode side metal plate 18 and the anode side resin frame 20 constitute an anode side separator 26. The cathode side metal plate 24 and the cathode side resin frame 22 constitute a cathode side separator 28. The metal plate 18 (or 24) and the resin frame 20 (or 22) are bonded to each other with a liquid gasket that constitutes the adhesive layer.

  The anode-side separator 26 includes a fuel gas supply manifold hole 30, a fuel gas discharge manifold hole 32, an oxidant gas supply manifold hole 34, an oxidant gas discharge manifold hole 36, a refrigerant manifold hole 38, and a fuel gas (a gas containing hydrogen). ) Is provided. The cathode separator 28 has a fuel gas supply manifold hole 42, a fuel gas discharge manifold hole 44, an oxidant gas supply manifold hole 46, an oxidant gas discharge manifold hole 48, a refrigerant manifold hole 50, and an oxidant gas (for example, An oxidant gas flow path 52 through which air flows is provided. The fuel gas flow path 40 and the oxidant gas flow path 52 are configured by the unevenness formed on the anode side metal plate 18 and the cathode side metal plate 24 and the side surfaces of the anode side resin frame 20 and the cathode side resin frame 22, respectively. The

  The membrane-electrode assembly 12 is also provided with a fuel gas supply manifold hole 54, a fuel gas discharge manifold hole 56, an oxidant gas supply manifold hole 58, an oxidant gas discharge manifold hole 60, and a refrigerant manifold hole 62. Furthermore, it is conventionally known to form a refrigerant flow path for flowing a refrigerant (for example, cooling water) through the separators 26 and 28. It has been conventionally known that a refrigerant flow path is provided for each fuel cell 10 or for each of a plurality of fuel cells 10. The refrigerant manifold holes 38, 50, 62 communicate with the refrigerant flow path.

  The fuel cell stack is provided with a current collector plate, an insulating plate, and an end plate (not shown) on both sides in a state where a plurality of fuel cells 10 are stacked, for example, a tension rod and a nut penetrating each stacked member, Tighten with. In this state, a plurality of manifold holes facing each other in the stacking direction of the fuel cells 10 communicate with each other, and a fuel gas supply manifold 64, a fuel gas discharge manifold 66, an oxidant gas supply manifold 68, and an oxidant gas discharge manifold 70. The refrigerant manifolds are respectively configured. Each of these manifolds 64, 66, 68, 70 is provided on an end plate at one end in the stacking direction of the fuel cell stack, a fuel gas inlet, a fuel gas outlet, an oxidant gas inlet, an oxidant gas outlet, a refrigerant inlet, and a refrigerant outlet. To each. Each manifold 64, 66, 68, 70 is provided in the stacking direction of the plurality of fuel cells 10 to be stacked. The fuel gas flow path 40 is branched from the fuel gas supply manifold 64 in a different direction, the oxidant gas flow path 52 is branched from the oxidant gas supply manifold 68 in a different direction, and the refrigerant flow path is The refrigerant branches from the refrigerant supply refrigerant manifold in a different direction.

  In such a fuel cell stack, for example, the fuel gas is fed into the fuel gas flow path 40 of the anode separator 26 by feeding the fuel gas into the fuel gas supply manifold 64 in the direction indicated by the arrow A in FIG. Then, the fuel gas is discharged to the outside through the fuel gas discharge manifold 66 in the direction indicated by the arrow b in FIG. Further, the oxidant gas is fed into the oxidant gas flow path 52 of the cathode side separator 28 by sending the oxidant gas in the direction indicated by the arrow C in FIG. Then, the oxidant gas is discharged to the outside through the oxidant gas discharge manifold 70 in the direction indicated by the arrow D in FIG. Fuel gas and oxidant gas are subjected to a cell reaction on both sides of the membrane-electrode assembly 12.

  In FIG. 10, in each fuel cell 10, the separators 26, 28 are constituted by the metal plates 18, 24 and the resin frames 20, 22, but the separators 26, 28 are made of one metal plate or carbon. It has been conventionally considered to use a plate made of a material. That is, as in the fuel cell stack described in Patent Document 2, the separator only needs to have sufficient conductivity, strength, and corrosion resistance. For example, the separator can be composed of a carbon material, a metal having corrosion resistance, or the like. .

Patent Document 3 describes that each fuel cell is configured by providing a pair of gaskets on both sides of a unit cell including an electrolyte membrane, an electrode, and a gas diffusion layer, and providing separators on both sides. Has been. Patent Document 4 describes that a unit cell configured in the same manner as Patent Document 3 is provided, and a packing is provided between one side outer peripheral part of the electrolyte membrane of this unit cell and one side outer peripheral part of the separator. .
As prior art documents related to the present invention, there are Patent Document 5 to Patent Document 6 in addition to Patent Document 1 to Patent Document 4.

JP 2005-353521 A JP 2004-200132 A JP 2000-331691 A JP 2003-77498 A JP 7-235314 A JP 2004-185811 A

  In the case of the structure described in Patent Document 1 to Patent Document 4, the separator and some members (metal plates 18, 24, resin frames 20, 22 and the like) constituting the separator are gas or refrigerant. It is formed in a shape including a manifold constituting surface (inner surface of a hole or the like) constituting a part of a fluid supply manifold and a fluid introduction surface. Of these, the fluid introduction surface is a surface that guides the fluid of the gas or the refrigerant from the fluid supply manifold to the gas passage or the refrigerant passage in a direction different from the inside of the manifold. However, such a separator or a member constituting the separator does not generate a burr on the front surface side that is one end side of the manifold constituting surface during shape molding, but on the back surface side that is the other end side of the manifold constituting surface. It is conceivable to manufacture by a molding method that generates burrs.

  For example, when the member constituting the separator is made of synthetic resin, the resin enters between the mating surfaces of the mold when molding this member, so that no burr is generated on the surface side that is one end side of the manifold constituting surface. In addition, it is conceivable to form the burrs on the back side that is the other end side. Further, when the member constituting the separator is made of metal, burrs are generated on the back surface side, which is the other end side, by punching holes, without generating burrs on the front surface side, which is the one end side of the manifold constituting surface. It can be considered to be molded as follows. However, in the structure described in Patent Document 1 to Patent Document 4, the side on which the burr is present is regulated in relation to the fluid introduction surface that guides the gas or refrigerant fluid to the gas flow path or the refrigerant flow path. Is not disclosed. Such a burr may prevent a fluid that is a gas or a refrigerant from smoothly flowing into the gas flow path or the refrigerant flow path from the fluid supply manifold. In this case, pressure loss (pressure loss) is likely to occur with respect to the flow of the fluid flowing in each fuel cell, and when the member constituting the separator is made of metal, corrosion may be likely to occur starting from the burr. There is sex.

  The inconvenience caused by the occurrence of such burrs will be described in more detail using the structure described in Patent Document 1 and a modification of this structure. That is, in the case of the structure described in Patent Document 1, as shown in FIG. 11, in each fuel cell 10, for example, the inlet side end of the fuel gas channel 40 is connected to the membrane-electrode assembly 12 and the anode side. The metal plate 18 is provided on the anode side metal plate 18 side (upper side in FIG. 11). In this case, as shown in FIG. 12, burrs 72 facing the fuel gas flow path 40 are formed in the periphery of the fuel gas supply manifold hole 30 on the resin frame 20 side, which is present at the inlet side end. There is a possibility that it will be in the state. In such a state, it is difficult for the fuel gas flowing in the fuel gas supply manifold 64 in the direction indicated by the arrow H in the drawing to smoothly flow into the fuel gas passage 40. For this reason, pressure loss (pressure loss) tends to occur with respect to the flow of the fuel gas flowing in each fuel cell 10.

  On the other hand, in FIG. 11, when the fuel gas flows in the manifold 64 in the direction opposite to the arrow in FIG. 11, the fuel gas flow path 40 side is located around the hole on the anode side metal plate 18 side of the manifold hole 30. There is a possibility that burrs are formed toward the surface. In such a state, the burrs tend to prevent the fuel gas from smoothly flowing into the fuel gas flow path 40. For this reason, pressure loss is likely to occur with respect to the flow of the fuel gas flowing in each fuel cell 10. In this case, there is also a problem that the metal plate 18 is likely to be corroded starting from this burr when the fuel gas contacts (collises) with the burr generated on the metal plate 18.

  As a modification of the structure shown in FIG. 11, as shown in FIG. 13, in each fuel cell 10, for example, the inlet side end of the fuel gas flow path 40 is connected to the membrane-electrode assembly 12 and the anode side metal plate 18. It is also conventionally considered to form them on the membrane-electrode assembly 12 side (the lower side in FIG. 13). In this case, the anode-side metal plate 18 and the anode-side resin frame 20, and the cathode-side metal plate 24 and the cathode-side resin frame 22 are bonded to each other via an adhesive layer 74 (see FIG. 14). Further, a fluid introduction surface 76 (see FIG. 14) for introducing fuel gas to the membrane-electrode assembly 12 side is provided on the surface of the anode-side resin frame 20 on the membrane-electrode assembly 12 side (lower side in FIG. 13). It will be in the provided state. In this case, as shown in FIG. 14, a burr 72 is provided at the peripheral portion of the fuel gas supply manifold hole 30 between the anode side metal plate 18 and the anode side resin frame 20 so as to face the opposite side of the mating members to be coupled to each other. If present, the burr 72 on the resin frame 20 side faces the fluid introduction surface 76 side. As a result, there is a problem that the fuel gas sent into the fuel gas supply manifold 64 is not easily smoothly introduced to the fluid introduction surface 76 side, and the pressure loss of the fuel gas is likely to occur.

  In this case, since the burr 73 generated in the anode side metal plate 18 faces to the opposite side of the flow of the fuel gas in the manifold 64, the fuel gas easily hits the burr 73 and tends to stay. There is a possibility. For such inconvenience, if the burr 73 on the metal plate 18 side is provided on the same side as the fuel gas flow (lower side in FIG. 14), the inconvenience caused by this burr 73 can be eliminated or suppressed. There is a possibility. However, simply adopting such a configuration is not sufficient to eliminate the disadvantage that the fuel gas is difficult to be introduced to the fluid introduction surface 76 side of the resin frame 20.

  The above description has explained the inconvenience caused by the burr 72 when the fuel gas flows from the fuel gas supply manifold 64 into the fuel gas flow path 40 of each fuel cell 10. However, when the oxidant gas flows from the oxidant gas supply manifold 68 into the oxidant gas flow path 52 (see FIG. 10) of each fuel cell 10, or from the refrigerant manifold for supplying the refrigerant to the refrigerant flow path. Even when the refrigerant flows, if there are burrs at the fluid introduction corner where the inner peripheral surface of the hole constituting the manifold and the oxidant gas flow path or the refrigerant flow path intersect, the same disadvantages as described above may occur. There is sex.

  The object of the present invention is to suppress pressure loss of a fluid that is a gas or a refrigerant flowing from the fluid supply manifold in a direction different from that in the fluid supply manifold, and even when made of metal, the corrosion caused by the fluid. An object of the present invention is to provide a fluid introduction member for a fuel cell stack capable of suppressing the above and a fuel cell stack having the same.

A fuel cell stack fluid introduction member according to the present invention flows along a manifold configuration surface that forms part of a fluid supply manifold that supplies a fluid that is a gas or a refrigerant to the inside of the fuel cell stack, and the manifold configuration surface. It has a shape that includes a fluid introduction surface that guides fluid in a different direction, and at the time of forming the shape, it does not generate a burr at one end of the front surface of the manifold constituting surface, and the periphery of the other end of the rear surface of the manifold constituting surface A fluid introducing member (resin frame, carbon material or metal separator, hard plate material called “sealing plate”, which will be described later), etc.
A fuel cell stack fluid introduction member characterized in that a fuel cell stack is configured with a surface on which no burrs are formed at an end of a manifold constituting surface at the time of shape forming as a fluid introduction surface.

  In the fuel cell stack fluid introduction member according to the present invention, preferably, a fuel cell is configured by stacking with other members, and a fuel cell stack is configured by stacking a plurality of sets of the fuel cells. To do.

  In the fuel cell stack fluid introduction member according to the present invention, preferably, the chamfering process is further performed on the fluid introduction corner where the manifold constituting surface and the fluid introduction surface intersect. More preferably, the fluid introduction corner is provided with a curved chamfer having a cross section of a composite arc whose radius of curvature increases toward the front with respect to the flow of fluid in the fluid supply manifold.

  In the fuel cell stack fluid introduction member according to the present invention, it is preferable that the fluid introduction member is made of a metal plate, and a hole is formed in the metal plate by punching, and an inner surface of the hole is a manifold constituting surface.

  In the fuel cell stack fluid introduction member according to the present invention, preferably, a synthetic resin is injection-molded into a shape having a hole, and the inner surface of the hole is a manifold constituting surface.

  The fuel cell stack according to the present invention includes a plurality of sets of fuel cell units each including an electrolyte membrane and a pair of separators provided on both sides of the electrolyte membrane, and a fluid that is a gas or a refrigerant A fluid supply manifold and a fluid introduction member. The fluid introduction member has a manifold constituting surface constituting a part of the fluid supply manifold, and a fluid flowing along the manifold constituting surface in a different direction. In the shape forming process, a burr is generated at the periphery of the other end of the manifold constituting surface on the back side without forming a burr at one end of the manifold constituting surface on the front side. In the fuel cell stack obtained as described above, the fluid introduction member is any one of the fluid introduction members for a fuel cell stack according to the present invention described above. Tsu is a click.

  According to the fuel cell stack fluid introduction member and the fuel cell stack according to the present invention, it is possible to suppress pressure loss of a fluid that is a gas or a refrigerant flowing from the fluid supply manifold in a direction different from that in the fluid supply manifold. Even when the fuel cell stack fluid introduction member is made of metal, corrosion due to the fluid can be suppressed.

[First Embodiment]
Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings. 1 to 4 show an embodiment of the first invention. In the present embodiment, the present invention is applied to a fuel cell stack in which a plurality of sets of fuel cells 10 as shown in FIGS. 13 to 14 are stacked. That is, in the present embodiment, the present invention is applied on the assumption that the fuel cell stack fluid introduction member is the anode-side resin frame 20 having the structure shown in FIGS. 13 to 14. The feature of the present embodiment is that the side where the burr 72 generated at the end of the hole 75 of the resin frame 20 is provided is restricted, and the burr 73 generated at the end of the hole 82 of the anode side metal plate 18 is further restricted. It is in the point which regulated the side to provide.

  The fuel cell stack of the present invention includes an electrolyte membrane, a membrane assembly 12 (see FIGS. 10 to 13) provided with an anode side electrode and a cathode side electrode provided on both sides thereof, and provided on both sides of the membrane assembly 12. A plurality of sets of fuel cells 10 are stacked as a set of fuel cells 10 in which the anode separator 26 and the cathode separator 28 (see FIG. 13) are stacked. Then, in a state where a plurality of sets of fuel cells 10 are stacked, current collector plates (not shown), insulating plates, and end plates are provided on both sides, for example, tightened by tension rods and nuts penetrating the stacked members. ing.

  Further, the anode side separator 26 is constituted by the anode side metal plate 18 and the anode side resin frame 20, and the cathode side separator 28 is constituted by the cathode side metal plate 24 and the cathode side resin frame 22 (see FIG. 13). ing. Further, inside the fuel cell stack, a fuel gas supply manifold 64 for supplying fuel gas to the inside, an oxidant gas supply manifold 68 (see FIG. 10) for supplying oxidant gas to the inside, and a refrigerant Refrigerant manifolds for supplying refrigerant to be supplied inside are provided in the stacking direction of the fuel cell stacks.

  Further, inside the fuel cell stack, a fuel gas discharge manifold 66 (see FIG. 10) for discharging fuel gas, an oxidant gas discharge manifold 70 (see FIG. 10) for discharging oxidant gas, and a refrigerant A refrigerant manifold for discharging refrigerant for discharging the fuel cell is provided in the stacking direction of the fuel cell stack. Each manifold 64, 68, 66, 70 communicates with a fuel gas inlet, a fuel gas outlet, an oxidant gas inlet, an oxidant gas outlet, a refrigerant inlet, and a refrigerant outlet of an end plate provided at one end of the fuel cell stack in the stacking direction. I am letting. The other basic configuration of the fuel battery cell 10 is the same as the structure shown in FIGS. 13 to 14 described above, and therefore, redundant description is omitted or simplified.

  The anode side resin frame 20 is provided with a hole 75 constituting the resin frame 20 side of the manifold hole 30 constituting the fuel gas supply manifold 64. Further, the anode side metal plate 18 is provided with a hole 82 constituting the metal plate 18 side of the manifold hole 30. The resin frame 20 also has a fluid introduction surface 76 that guides the fuel gas flowing in the fuel gas supply manifold 64 to the fuel gas flow path 40. In this way, the anode-side resin frame 20 having a shape including the hole 75 and the fluid introduction surface 76 has a burr formed on the surface 77 side which is one end (the lower end in FIG. 1) side of the hole 75 during the shape forming described later. Without forming it, it is manufactured by a molding method in which a burr 72 is generated on the back surface 78 side which is the other end (upper end in FIG. 1) side of the hole 75. Then, a fuel cell 10 and a fuel cell stack formed by laminating a plurality of sets of the fuel cells 10 are formed by using, as a fluid introduction surface 76, a surface 77 where no burr is generated at the end of the hole 75 at the time of shape forming. Constitute. Therefore, there is no burr at the fluid introduction corner 80 where the inner peripheral surface of the hole 75 and the fluid introduction surface 76 intersect. In the case of the present embodiment, the inner peripheral surface of the hole 75 corresponds to the “manifold constituting surface” recited in the claims.

  Further, the fluid introduction corner 80 is further chamfered to form a chamfer having a substantially arc-shaped cross section. Preferably, the fluid introduction corner 80 is provided with a curved chamfer having a cross section of a composite arc whose curvature radius increases toward the front with respect to the flow of fuel gas in the manifold 64. Further, in the case of the present embodiment, in the anode side metal plate 18, the burrs 73 generated around the holes 82 constituting the fuel supply manifold holes 30 are projected to the anode side resin frame 20 side. Provided. Since the burr 73 generated in the anode side metal plate 18 is generated on the front side in the punching direction when the hole 82 constituting the manifold hole 30 is punched, the front side in the punching direction is set to the side facing the resin frame 20. Therefore, the side where the burr 73 is provided can be easily regulated.

  Next, a method for forming the resin frame 20 will be described with reference to FIGS. In the case of the present embodiment, the resin frame 20 is made of a thermosetting resin. In this case, the upper mold 84 as shown in FIG. 2 and the lower mold 86 as shown in FIG. 3 are used, and a set of granular raw materials of thermosetting resin in a state where the upper mold 84 and the lower mold 86 are heated. As shown in FIG. 4, a resin frame 20 having a predetermined shape is made. At the time of forming the shape of the resin frame 20, as shown in FIG. 4, the material that becomes the resin frame 20 is pressurized between the upper mold 84 and the lower mold 86, but the fuel gas supply manifold hole 30 (see FIG. 1). The aggregates of the granular raw materials are solidified while entering between the mating surfaces of the upper die 84 and the lower die 86 in the peripheral portion of the end portion of the hole 75 constituting the hole 75. In this case, the upper surface in FIG. 4 of the resin frame 20 is the front surface 77 and the lower surface in FIG. Since the resin frame 20 is manufactured by such a molding method, a burr 72 is generated around the other end of the hole 75 on the back surface 78 side without generating a burr at one end of the hole 75 on the front surface 77 side. In the case of the present embodiment, as shown in FIG. 1, the back surface 78 on which the burr 72 is generated is the surface opposite to the fluid introduction surface 78 and the burr is formed at the end of the hole 75. The non-generated surface 77 is used as the fluid introduction surface 76 to constitute the fuel cell 10 and the fuel cell stack.

  According to the fuel cell stack fluid introduction member of the present embodiment as described above and the fuel cell stack provided with the same, the burr 72 generated in the resin frame 20 has the fluid introduction surface 76 and the inner peripheral surface of the hole 75. Since it does not exist at the intersecting fluid introduction corner 80, the flow of the fuel gas flowing from the fuel gas supply manifold 64 into the fuel gas flow path 40 (FIG. 1) oriented in a direction different from the inside of the fuel gas supply manifold 64. Is less likely to be disturbed by burrs. For this reason, the pressure loss in each fuel cell 10 of this fuel gas can be suppressed.

  Further, in the case of the present embodiment, the burr 73 present in the periphery of the hole 82 constituting the manifold hole 30 of the anode side metal plate 18 is provided on the resin frame 20 side. Further, the flow of the fuel gas in the manifold 64 can be prevented from being hindered. For this reason, the pressure loss with respect to the flow of the fuel gas in the manifold 64 can also be reduced.

  In the present embodiment, the anode side metal plate 18 and the anode side resin frame 20 are bonded via the adhesive layer 74, but a predetermined shape is formed between the metal plate 18 and the resin frame 20. A gasket or the like may be provided. Further, in the above, when the fuel gas flows from the manifold 64 into the fuel gas flow path 40 of each fuel cell 10, the side on which the burr 72 of the resin frame 20 is generated is regulated in relation to the fluid introduction surface 76. is doing. However, the member which has the hole which comprises the oxidant gas supply manifold 68, and the fluid introduction surface which introduce | transduces oxidant gas to the oxidant gas flow path 52 (refer FIG. 10), and the hole which comprises the refrigerant | coolant manifold for refrigerant | coolant supply And a member having a fluid introduction surface that guides the refrigerant to the refrigerant flow path, the back surface on which the burr is generated in the peripheral portion of the end portion of the hole is a surface opposite to the fluid introduction surface, and the end portion of the hole By configuring the fuel cell and the fuel cell stack using the surface where no burr is generated as the fluid introduction surface, the same effect as in the present embodiment can be obtained.

For example, a coolant channel is formed on the surface (upper surface in FIG. 1) of the anode side metal plate 18 opposite to the membrane-electrode assembly 12 (see FIG. 13), and holes constituting a coolant manifold for supplying coolant are formed. When formed, a burr protruding on the back surface opposite to the refrigerant flow path is provided at the periphery of the hole of the anode side metal plate 18, and a fluid introduction corner where the refrigerant flow path and the hole intersect. Do not provide burrs. The refrigerant flow path is configured by overlapping the side surface of the cathode side metal plate constituting another fuel battery cell on the surface of the anode side metal plate 18 on the refrigerant flow path side.
In the present embodiment, preferably, all the fuel cells 10 constituting the fuel cell stack adopt the same configuration as that of the present embodiment. Of course, by adopting this configuration, the effect of the present embodiment becomes more prominent.

[Second Embodiment]
1 shows a case where the burr 72 generated in the peripheral portion of the hole 75 of the resin frame 20 is protruded in a direction substantially parallel to the axial direction of the hole 75. However, as shown in FIG. 5, the burr 72 may occur in a state of protruding in a direction substantially orthogonal to the axial direction of the hole 75 constituting the manifold hole 30 (see FIG. 1). That is, when the hole 75 is formed by abutting the tip of the protrusion 88 of the upper mold 84 against the upper surface of the lower mold 86, the gap between the mating surfaces of the lower surface of the upper mold 84 and the upper surface of the lower mold 86 is between. A set of granular raw materials of the thermosetting resin enters and is solidified. As a result of this solidification, burrs 72a are generated. In this case, the burr 72a protrudes in a direction substantially orthogonal to the axial direction of the hole 75.

In the case of the embodiment of the second invention shown in FIG. 6, the surface 77 of the resin frame 20 made by a molding method in which such a burr 72a is generated, where no burr is generated at the end of the hole 75. The fuel cell 10 and the fuel cell stack are configured with the fluid introduction surface 76 and the back surface 78 on which the burr 72 a is generated at the end of the hole 75 as the surface opposite to the fluid introduction surface 76. As a result, the flow of the fuel gas flowing from the fuel gas supply manifold 64 into the fuel gas flow path 40 can be made smooth, and substantially the same effect as in the first embodiment can be obtained.
Since other configurations and operations are the same as those of the first embodiment shown in FIG. 1, the same parts are denoted by the same reference numerals, and redundant description is omitted.

[Third Embodiment]
Next, FIG. 7 shows an embodiment of the third invention. In the case of the present embodiment, the present invention is applied in a structure similar to the structure described in Patent Document 5. That is, in the case of the present embodiment, each fuel cell 10 is provided on both sides of the electrolyte membrane 90, the anode-side resin frame 92 and the cathode-side resin frame 93 that support the outer peripheral edge of the electrolyte membrane 90, and the electrolyte membrane 90. Electrodes 94, 94 provided, and two collector electrodes 96, 96 provided on both sides of the electrolyte membrane 90 and the electrodes 94, 94 are provided. The collector electrodes 96 and 96 and the electrodes 94 and 94 form a fuel gas flow path 40 through which fuel gas flows and an oxidant gas flow path 52 through which oxidant gas flows. Further, the anode side separator 26 and the cathode side separator 28 are provided outside the collector electrodes 96, 96, and the seal member 102 is provided between the outer peripheral portions of the separators 26, 28 and the resin frames 92, 93.

  Further, the protrusions 104, 104 are provided on the surfaces of the resin frames 92, 93 facing each other, the tips of the protrusions 104, 104 facing each other are welded together, and a part of the welding portion and the electrolyte membrane 90 are integrated. It has become. Further, a fluid introduction surface 76 for introducing fuel gas to the electrolyte membrane 90 and the electrode 94 side is provided on the anode side separator 26 side (the upper side in FIG. 7) of the anode side resin frame 92. In contrast, a fluid introduction surface (not shown) for introducing an oxidant gas to the electrolyte membrane 90 and the electrode 94 side is provided on the cathode side separator 28 side (lower side in FIG. 7) of the cathode side resin frame 93. ing. Further, the groove provided on the fluid introduction surface 76 of the anode side resin frame 92 and the groove (not shown) provided on the fluid introduction surface of the cathode side resin frame 93 are formed in directions orthogonal to each other.

  In the case of the present embodiment, in such a structure, when the shape of the anode side resin frame 92 is formed, the surface is the same as in the case of the first embodiment shown in FIGS. A burr 72 is generated around the other end of the hole 106 on the back surface 78 side without generating a burr on one end of the hole 106 constituting the fuel gas supply manifold 64 on the 77 side. Then, the fuel cell 10 and the fuel cell stack are configured with the surface 77 at the time of shape forming as the fluid introduction surface 76. Further, a chamfering process is performed on the fluid introduction corner 80 where the inner circumferential surface of the hole 106 and the fluid introduction surface 76 intersect to form a chamfer having a substantially arc-shaped cross section.

  In the case of this embodiment as well, the flow when gas is fed from the fuel gas supply manifold 64 into the fuel gas flow path 40 can be prevented from being hindered. For example, when the fuel gas flows in the manifold 64 in the direction indicated by the arrow in FIG. 7, the fuel gas can be smoothly fed to the fluid introduction surface 76 side. For this reason, the pressure loss in each fuel cell 10 of this fuel gas can be suppressed.

[Fourth Embodiment]
Next, FIG. 8 to FIG. 9 show an embodiment of the fourth invention. In the present embodiment, the present invention is applied with the fluid introduction member for the fuel cell stack as the sealing plate 108. In the case of this embodiment, the present invention is applied in a structure similar to the structure described in Patent Document 5. That is, in the case of the present embodiment, each fuel cell 10 includes a membrane-electrode assembly 12 comprising an electrolyte membrane and electrodes provided on both sides of the electrolyte membrane, and an anode side provided on both sides of the membrane-electrode assembly 12. The separator 26 and the cathode side separator 28, and the sealing plate 108 provided between the anode side separator 26 and the electrolyte membrane are provided. Further, the anode-side reaction gas diffusion layer 14 and the cathode-side reaction gas diffusion layer 16 are provided between the membrane-electrode assembly 12 and the anode-side separator 26 and the cathode-side separator 28.

  Each of the separators 26 and 28 is composed of a single plate-like member made of a carbon material as shown in the figure, or a combination of a metal plate and a resin plate, or a single material made of metal, conductive resin, or the like. You may comprise by a plate-shaped member. The anode side separator 26 has a fuel gas flow path 40 for supplying fuel gas to the anode side electrode, and the cathode side separator 28 has an oxidant for supplying oxidant gas to the cathode side electrode. A gas flow path 52 is formed. Each of the separators 26 and 28 is also formed with a refrigerant flow path (not shown) for flowing a refrigerant. In addition to providing the refrigerant flow path for each fuel cell 10, one or a plurality of refrigerant channels can be provided for each of the plurality of fuel cells 10.

  Further, the separators 26 and 28 are formed with holes 110 and 110 constituting a manifold 64 through which any one of refrigerant, fuel gas, and oxidant gas flows. Each hole 110 communicates with any one of the coolant channel, the fuel gas channel 40, and the oxidant gas channel 52. Further, the gas flow path 40 and the gas supply manifold 64 are communicated with each other by the communication gas flow path 112. The communication gas flow path 112 is configured by a groove 114 provided on the sealing plate 108 side of the anode side separator 26 and a fluid introduction surface 116 of the sealing plate 108. The sealing plate 108 is a hard plate made of an electrically insulating material such as synthetic resin. Further, an adhesive 118 seals between the sealing plate 108 and the electrolyte membrane, between the cathode separator 28 and the sealing plate 108, and between the outer peripheral portions of the separators 26 and 28. Note that if a sealing member such as packing is provided between the sealing plate 108 and the electrolyte membrane, the sealing plate 108 can be made of a conductive material such as metal.

  In the present embodiment, in such a structure, when the sealing plate 108 is formed, the burrs are formed on one end (the lower end in FIGS. 8 to 9) of the side wall surface 119 constituting the fuel gas supply manifold 64 on the surface side. The burr | flash 120 is produced in the other end (upper end of FIGS. 8-9) peripheral part of the side wall surface 119 at the back surface 122 side. The fuel cell 10 and the fuel cell stack are configured with the surface where the burr is not generated at the end of the side wall surface 119 during the shape forming as the fluid introduction surface 116. Further, a chamfering process is performed on the fluid introduction corner 80 where the side wall surface 119 and the fluid introduction surface 116 intersect to form a chamfer having a substantially arc-shaped cross section. In the case of the present embodiment, the side wall surface 119 of the sealing plate 108 corresponds to the manifold constituting surface described in the claims.

  In the case of this embodiment as well, the flow of gas when gas is fed from the manifold 64 into the gas flow path 40 can be prevented from being hindered. For example, when the fuel gas flows in the manifold 64 in the direction indicated by the arrow in FIG. 8, the fuel gas can be smoothly fed into the fluid introduction surface 116 side. Therefore, the pressure loss of the fuel gas in each fuel cell 10 can be suppressed, and even when the sealing plate 108 is made of metal, corrosion based on burrs can be hardly caused.

  In each of the above embodiments, the case where the side where the burrs 72 and 120 generated on the resin frames 20 and 92 or the sealing plate 108 exist is regulated in relation to the fluid introduction surfaces 76 and 116 has been described. However, the present invention is not limited to such a structure. For example, a fuel cell stack fluid introduction member may be a metal separator called a “metal separator” or a carbon material separator called a “carbon separator”. In this case, in the case of having a hole that constitutes a fluid supply manifold and a fluid introduction surface that guides the fluid to the gas flow path or the refrigerant flow path, the back surface in which the burr is generated around the end of the hole is fluidized. The fuel cell and the fuel cell stack can also be configured using a surface opposite to the introduction surface and a fluid introduction surface that is a surface where no burr is generated at the end of the hole.

  For example, in the case of the fourth embodiment shown in FIGS. 8 to 9, the back surface where burrs are generated at the point P (FIG. 8) of the anode separator 26 made of a carbon material is used as a fluid introduction surface. The surface on which the burrs are not formed at the point Q (FIG. 8) may be the surface opposite to the surface on which the groove 114 is formed. Even in the case of a fluid introduction member made of carbon material such as the anode separator 26 made of carbon material, the raw material of the carbon material enters between the mating surfaces of the mold when the separator 26 is molded, and burrs are generated. There is a case. In the present invention, by controlling the side where such burrs are generated in relation to the fluid introduction surface, substantially the same effects as those of the above embodiments can be obtained.

  Further, when the separator is made of a metal such as stainless steel, it is possible to prevent the separator from being corroded by using the burr as a base point by preventing the burr from being present at the fluid introduction corner of the separator. That is, the burr portion is more susceptible to corrosion (reactive activity) than the flat portion, and the burr is likely to be a growth starting point of corrosion. According to the present invention, it is possible to easily suppress the occurrence of such corrosion. For example, a hole made up of a manifold for fluid supply is formed by punching a separator made of metal, and the back surface where burrs are generated at the periphery of the end of the hole is the surface opposite to the fluid introduction surface. The fuel cell and the fuel cell stack can also be configured with the surface where no burr is formed at the end of the fuel cell as the fluid introduction surface.

  Further, the fuel cell stack fluid introduction member can be formed by injection molding a synthetic resin, and can also be formed into a shape having holes forming a manifold by this injection molding. In such a fuel cell stack fluid introduction member, a burr generated at the periphery of the hole is provided only on the side opposite to the fluid introduction surface, and a fluid introduction corner portion where the fluid introduction surface and the inner peripheral surface of the hole intersect. Can also be made free of burrs.

14 is a view similar to FIG. 14 showing exaggerated burrs when a fuel cell is configured by combining a resin frame, which is a fluid introduction member for a fuel cell stack according to an embodiment of the first invention, with a metal plate. is there. It is sectional drawing which shows the upper mold for shaping | molding of a resin frame. It is a front view which similarly shows a lower mold | type. It is a fragmentary sectional view which exaggerates the burr | flash and shows the state which shape | molds the resin frame using an upper mold | type and a lower mold | type. FIG. 5 is a partial cross-sectional view in which a resin frame is molded using an upper mold and a lower mold having shapes different from those in FIG. FIG. 6 is a view similar to FIG. 1, showing an embodiment of the second invention using a resin frame in which burrs are generated as shown in FIG. 5. It is a fragmentary sectional view which shows the fuel cell which comprised the resin frame which is the fluid introduction member for fuel cell stacks of embodiment of 3rd invention combining with the other member. It is a fragmentary sectional view which shows the fuel cell formed by combining the sealing plate which is the fluid introduction member for fuel cell stacks of Embodiment of 4th invention with the other member. It is a partial exploded perspective view of a fuel cell similarly. It is a disassembled perspective view which shows an example of the fuel cell of a conventional structure. It is a figure which shows one example of the flow state of the gas of the fuel battery cell of FIG. FIG. 12 is an enlarged cross-sectional view of a portion A in FIG. 11 for explaining inconvenience caused by the generation of burrs. It is a figure which shows one example of the flow state of the gas of the modification of the fuel battery cell of FIG. It is the B section expanded sectional view of Drawing 13 for explaining the inconvenience which arises by generating a burr.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Fuel cell, 12 Membrane-electrode assembly, 14 Anode side reaction gas diffusion layer, 16 Cathode side reaction gas diffusion layer, 18 Anode side metal plate, 20 Anode side resin frame, 22 Cathode side resin frame, 24 Cathode side metal plate , 26 Anode separator, 28 Cathode separator, 30 Fuel gas supply manifold hole, 32 Fuel gas discharge manifold hole, 34 Oxidant gas supply manifold hole, 36 Oxidant gas discharge manifold hole, 38 Refrigerant manifold hole, 40 Fuel gas flow , 42 Fuel gas supply manifold hole, 44 Fuel gas discharge manifold hole, 46 Oxidant gas supply manifold hole, 48 Oxidant gas discharge manifold hole, 50 Refrigerant manifold hole, 52 Oxidant gas flow path, 54 Fuel gas supply manifold hole , 56 Fuel gas discharge manifold hole, 58 Oxidant gas supply manifold hole, 60 Oxidant gas discharge manifold hole, 62 Refrigerant manifold hole, 64 Fuel gas supply manifold, 66 Fuel gas discharge manifold, 68 Oxidant gas supply manifold, 70 Oxidant Gas exhaust manifold, 72, 72a Burr, 73 Burr, 74 Adhesive layer, 75 holes, 76 Fluid introduction surface, 77 Surface, 78 Back surface, 80 Fluid introduction corner, 82 holes, 84 Upper mold, 86 Lower mold, 88 Projection Part, 90 electrolyte membrane, 92 anode side resin frame, 93 cathode side resin frame, 94 electrode, 96 collector electrode, 102 seal member, 104 protrusion, 106 holes, 108 sealing plate, 110 holes, 112 communication gas flow path, 114 Groove, 116 Fluid introduction surface, 118 Adhesive 119 side wall surface, 120 burr, 122 backside.

Claims (6)

A shape including a manifold constituting surface that constitutes a part of a fluid supply manifold that supplies a fluid that is gas or refrigerant to the inside of the fuel cell stack, and a fluid introduction surface that guides the fluid flowing along the manifold constituting surface in another direction. And a fluid introducing member obtained by forming a burr on the periphery of the other end of the manifold constituting surface on the back surface side without forming a burr on one end of the manifold constituting surface on the back surface side during shape forming Because
A fluid introduction member for a fuel cell stack, wherein a fuel cell stack is constituted by using a surface where no burr is generated at an end of a manifold constituting surface at the time of shape forming as a fluid introduction surface.   The fluid introduction member for a fuel cell stack according to claim 1, wherein a fuel cell is configured by stacking with other members, and further, a fuel cell stack is configured by stacking a plurality of sets of the fuel cells. A fluid introduction member for a fuel cell stack.   3. The fuel cell stack fluid introduction member according to claim 1 or 2, wherein a chamfering process is further applied to a fluid introduction corner where the manifold constituting surface and the fluid introduction surface intersect. Fluid introduction member.   4. The fuel cell stack fluid introduction member according to claim 1, wherein the fuel cell stack fluid introduction member is formed of a metal plate, and a hole is formed in the metal plate by punching, and an inner surface of the hole is a manifold structure. A fluid introduction member for a fuel cell stack, wherein the fluid introduction member is a surface.   The fluid introduction member for a fuel cell stack according to any one of claims 1 to 3, wherein a synthetic resin is injection molded to form a hole, and an inner surface of the hole is a manifold constituting surface. A fluid introduction member for a fuel cell stack. Laminating a plurality of sets of a set of fuel cells including an electrolyte membrane and a pair of separators provided on both sides of the electrolyte membrane,
A fluid supply manifold for supplying a fluid, which is a gas or a refrigerant, and a fluid introduction member;
The fluid introducing member has a shape including a manifold constituting surface constituting a part of the fluid supply manifold and a fluid introducing surface for guiding the fluid flowing along the manifold constituting surface in another direction. It is obtained without causing burrs at one end of the manifold constituting surface on the front side, but generating burrs around the other end of the manifold constituting surface on the back side.
In the fuel cell stack,
A fuel cell stack, wherein the fluid introduction member is a fluid introduction member for a fuel cell stack according to any one of claims 1 to 5.

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