JP2008091104A - Plate for fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a plate for a fuel cell which is arranged so that gas leakage does not occur between neighboring reaction gas flow passages in tunnel like reaction gas flow passages formed by mounting a flat plate on the plate. <P>SOLUTION: By, for example, interposing a sheet material 13 serving as sealing means in a recessed part 6h installed at an anode side plate 6 corresponding to a shape of the flat plate 12, the flat plate 12 is mounted, and by covering an inlet region of a fuel introduction passage 6d, an inlet side manifold 6e, and fuel gas flow passages 6a, the tunnel like gas flow passages are formed. At this time, the upper face of the flat plate 12 is made to be flush with the upper face of the anode side plate 6. The sheet material 13 is formed into a double sided adhesive sheet, mounted together with the flat plate 12 by an adhesive means, and adhered closely to the upper faces of ribs 6i positioned between the respective fuel gas flow passages 6a. By this, at the inlet region of the fuel gas flow passages 6a, the gas leakage can be prevented from occurring between the fuel gas flow passages 6a neighboring under the flat plate 12, and a nearly uniform fuel gas becomes enabled to be supplied to a reaction part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a plate for a fuel cell. In particular, in a tunnel-like gas flow path formed by attaching a flat plate to the plate, there is no reaction gas leak between adjacent gas flow paths under the flat plate. The present invention relates to a fuel cell plate.

In a polymer electrolyte fuel cell, an anode electrode is provided on one side of a polymer electrolyte membrane and a cathode electrode is provided on the other side to form a membrane electrode assembly (MEA). A battery stack is formed by constituting a cell and stacking and integrating a large number of single cells.
The two plates are each provided with a groove-shaped gas flow path on the surface in contact with the membrane electrode assembly. Of these, fuel gas flows through the gas flow path of the plate on the anode electrode side, and on the cathode electrode side. Oxidant gas flows through the gas flow path of the plate. The fuel gas and the oxidant gas are configured to generate electric power by causing an electrochemical reaction through the polymer electrolyte membrane.

  In the polymer electrolyte fuel cell, it is necessary to allow the reaction gas (fuel gas and oxidant gas) to flow uniformly through the gas flow paths of the plate in order to improve the power generation performance. For this reason, a flat plate (referred to as a bridge plate or a cover plate) is attached to the inlet region of a plurality of gas passages in a bridging state to form a tunnel-like gas passage. By preventing the gasket from dropping into the flow path, the amount of reaction gas flowing through each gas flow path is averaged and supplied to the reaction section.

The flat plate is attached by welding or bonding means as disclosed in Patent Document 1, for example. In addition, a technique is disclosed in which a gasket made of a resin film and rubber is attached to a flat plate via an adhesive so as not to leak gas from the tunnel-shaped flow path region to which the flat plate is attached.
JP 2005-56584 A

  According to the prior art as described above, welding ribs are provided on both sides of a plurality of gas flow path regions in the separator, and a flat plate is welded to the welding ribs to fill a gap between the separator and the flat plate (bridge plate), The separator and the flat plate are integrated. In this case, since both sides of the flat plate are welded to the welding rib, a gap may be generated between the lower surface of the flat plate and the upper surface of the rib located between the gas flow paths due to the influence of heat or the like. When such a gap is generated, a phenomenon occurs in which a part of the reaction gas flowing through the gas flow channel leaks into the adjacent gas flow channel. For this reason, the flow rate of the reaction gas flowing through each tunnel-like gas flow path becomes non-uniform, leading to a decrease in power generation performance. Moreover, even if a gasket is affixed on a flat plate as described above, it is not possible to prevent gas leakage between adjacent gas passages in the tunnel-like gas passage region.

  The present invention was made in order to eliminate the disadvantages of the prior art, and in a tunnel-like reaction gas channel formed by attaching a flat plate to a plate, an adjacent reaction gas flow channel under a flat plate is provided. An object of the present invention is to provide a plate for a fuel cell in which no gas leak occurs between them.

  As a means for achieving the above object, the invention of claim 1 is directed to a fuel cell plate in which a flat plate is attached to an end of a plurality of gas passages arranged in parallel to form a tunnel-like gas passage. In this case, a sealing means is interposed between the flat plate and the gas flow path region covered by the flat plate, and the reaction gas flowing through each gas flow path is transferred to the adjacent gas flow path under the flat plate by the sealing means. It is characterized by preventing gas leakage.

  According to a second aspect of the present invention, in the fuel cell plate according to the first aspect, the sealing means is composed of a sheet material, and the sheet material is closely attached to the upper surface of each rib located between the flat plate and the gas flow path. And

  The invention of claim 3 is the fuel cell plate according to claim 2, wherein the sheet material is a styrene-isoprene-styrene (SIS) copolymer, a styrene-butadiene-styrene (SBS) copolymer, or a styrene-butylene- Rubber with ethylene-styrene (SEBS) copolymer as the main component, or ethylene-propylene-diene rubber (EPDM), hydrogenated acrylonitrile-butadiene rubber (HNBR), silicon rubber, fluorine rubber, etc. It is a double-sided adhesive sheet made of a material mixed with an agent.

  In the fuel cell plate according to claim 2 or 3, when the pressure loss of the gas flow path under the flat plate is within 30% of the total pressure loss of the gas flow path, The reduction in the cross-sectional area of the flow path due to the projection of the sheet material into each gas flow path is suppressed to 20% or less of the cross-sectional area of the flow path.

  According to the first aspect of the invention, when a flat plate is attached to the end of a plurality of gas flow paths arranged in parallel to form a tunnel-like gas flow path, a sealing means is provided between the flat plate and the separator. Therefore, it is possible to securely seal between the tunnel-like gas flow paths. This prevents the reaction gas flowing through each tunnel-shaped gas flow path from leaking into the adjacent gas flow path under the flat plate, and makes the flow rate of the reaction gas flowing through each gas flow path substantially uniform. A decrease in power generation performance can be suppressed.

  According to the invention of claim 2, the sealing means is composed of a sheet material, and the sheet material is in close contact with the upper surface of each rib located between the gas flow paths. There is no gap between the ribs located between the roads. Thereby, it is possible to reliably prevent the reaction gas flowing through each tunnel-like gas flow path from leaking into the adjacent gas flow path under the flat plate.

  According to the invention of claim 3, the sheet material is made of styrene-isoprene-styrene (SIS) copolymer, styrene-butadiene-styrene (SBS) copolymer, styrene-butylene-ethylene-styrene (SEBS) copolymer. Double-sided rubber consisting mainly of coalesce, etc., or made of a material that contains ethylene-propylene-diene rubber (EPDM), hydrogenated acrylonitrile-butadiene rubber (HNBR), silicon rubber, fluorine rubber, etc., and a tackifier. It can be composed of an adhesive sheet.

  According to invention of Claim 4, when the pressure loss of the gas flow path under a flat plate is less than 30% among the total pressure loss of the said gas flow path, it is by the protrusion to each gas flow path by the said sheet | seat material. By suppressing the decrease in the cross-sectional area of the flow path to 20% or less of the cross-sectional area of the flow path, the flow of the reaction gas flowing through each tunnel-shaped gas flow path is not hindered.

Next, an embodiment of a fuel cell plate according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a schematic exploded cross-sectional view showing the configuration of a fuel cell stack. In this case, three unit cells are stacked. In this figure, a single cell 1 includes a membrane electrode assembly 5 formed by joining and integrating an anode electrode 3 on one side of a polymer electrolyte membrane 2 and a cathode electrode 4 on the other side, with an anode side plate 6 and a cathode side plate 7. It is configured to be sandwiched.

  The anode side plate 6 is provided with a plurality of concave groove-like fuel gas flow paths 6a for flowing fuel gas in parallel on the surface side in contact with the anode electrode 3, and the cooling water flow on the surface side not in contact with the anode electrode 3 A plurality of common groove-shaped cooling water flow paths 6b are provided in parallel. Of the plurality of concave groove-like fuel gas flow paths 6a, the portions of the inlet region covered by the flat plate 12 to be described later are formed so that the flow channel width is slightly narrower than the other region portions, and the nozzle function is provided. ing. The cathode side plate 7 is provided with a plurality of concave groove-like oxidant gas flow paths 7a for flowing the oxidant gas in parallel on the surface side in contact with the cathode electrode 4, and the surface side not in contact with the cathode electrode 4 is It is formed on the flat surface 7b. The inlet region portion of the oxidant gas flow path 7a in the cathode side plate 7 is also formed with a slightly narrow flow path width to provide a nozzle function.

  Reference numeral 8 denotes a first cooling plate, and a plurality of recessed groove-shaped cooling water flow paths 8a for circulating cooling water are provided in parallel on the surface side contacting the flat surface 7b of the cathode side plate 7, and the flat surface 7b of the cathode side plate 7 is provided. The surface side that does not contact is formed on the flat surface 8b. 9 is a 2nd cooling plate, The surface side which contacts the formation surface of the cooling water flow path 6b in the said anode side plate 6, and the opposite surface side are all formed in the planes 9a and 9b.

  Then, as shown in FIG. 1, the first cooling plate 8 and the second cooling plate 9 are arranged on both sides with three unit cells 1 interposed therebetween, and a current collector plate 10a is further attached to the inner surface side. The first clamping plate 10 and the second clamping plate 11 having the current collector plate 11a attached to the inner surface side are arranged and laminated on both sides, and are tightened and integrated with through bolts and nuts (not shown) to integrate the battery. A stack is formed.

  FIG. 2 is a plan view of the anode side plate 6, where (a) shows the surface side where the fuel gas flow path 6 a is formed, and (b) shows the surface side where the cooling water flow path 6 b is formed. ing. In this figure (a), 12 is a flat plate, the inlet area | region of the fuel gas flow path 6a, the fuel introduction path 6d formed in the shape of a concave groove connected to the fuel supply hole 6c, and this fuel introduction opening 6d It is formed in a shape that can simultaneously cover the outlet side manifold 6e that communicates with the outlets of the plurality of fuel gas passages 6a and is formed in a concave groove shape. Note that a protrusion 6f that regulates the inflow amount of the fuel gas supplied from the fuel supply hole 6c is provided in a substantially central portion of the fuel introduction path 6d along the fuel introduction path 6d in substantially the first half of the fuel introduction path 6d. In the substantially central portion of the inlet side manifold 6e, a protrusion 6g is provided for dispersing the fuel gas flowing into the inlet side manifold 6e from the fuel introduction path 6d to the inlets of the fuel gas flow paths 6a.

  The flat plate 12 is made of, for example, a thin metal plate or resin plate, and a sheet material 13 as a sealing means is interposed in a recess 6h provided in the anode side plate 6 corresponding to the shape of the flat plate 12 as shown in FIG. Let it attach.

  The sheet material 13 is, for example, a rubber sheet mainly composed of SIS copolymer, SBS copolymer, SEBS or the like, or ethylene-propylene-diene rubber (EPDM), hydrogenated acrylonitrile-butadiene rubber (HNBR), silicon rubber, fluorine. Non-adhesive sheets such as rubber can also be used, but preferably rubber mainly composed of SIS copolymer, SBS copolymer, SEBS, etc., or ethylene-propylene-diene rubber (EPDM), hydrogenated acrylonitrile-butadiene rubber A double-sided adhesive sheet made of a material in which (HNBR), silicon rubber, fluororubber or the like is a main component and a tackifier is blended. Gas leakage to the adjacent gas flow path under the flat plate 12 is prevented by a double-sided adhesive sheet material and a plurality of linear gaskets (see FIG. 6) which are described later and have a pressing area equal to or smaller than the gas flow path area under the flat plate 12. It is suitable for doing.

  When the sheet material 13 is a double-sided adhesive sheet, the sheet material 13 is dropped into the recess 6h provided in the anode side plate 6 and is covered with the flat plate 12, and is applied to the anode side plate 6 together with the flat plate 12 by applying an appropriate pressure. . At this time, the upper surface of the flat plate 12 and the upper surface of the anode side plate 6 are made to be flush with each other.

  By this bonding, the lower surface side of the sheet material 13 is in close contact with the upper surfaces of the ribs 6i located between the fuel gas flow paths 6a as shown in FIG. . Thereby, it is possible to prevent the fuel gas passing through the inlet region of each fuel gas passage 6a from leaking into the adjacent fuel gas passage 6a under the flat plate 12. In addition, a plate and a flat plate (sheet material is unnecessary) are formed of a material mainly composed of a thermoplastic resin, and the flat plate is attached to the plate by welding means to constitute a tunnel-like gas flow path that prevents gas leakage. It is also possible. Examples of the thermoplastic resin include polymethylpentene, polypropylene, polyolefin, polyamide, amorphous polyester, polyphenylene oxide, polyphenylene sulfide, liquid crystal polyester, polyether ketone, polyether ether ketone, polysulfone, polyether sulfone, and polyetherimide. Can be mentioned. As the welding means, for example, hot plate welding, laser welding, ultrasonic welding, infrared welding, or the like can be used.

Due to appropriate pressurization at the time of attachment, a portion of the lower surface side of the sheet material 13 that faces each fuel gas flow channel 6a protrudes substantially uniformly into each fuel gas flow channel 6a as shown in FIG. 4B. . The protruding amount of the sheet material 13 is suppressed to 20% or less of the flow path sectional area W of the fuel gas flow path 6a as shown in FIG. Of the total pressure loss of the gas flow path, when the pressure loss of the gas flow path under the flat plate is within 30%, if the protruding amount of the sheet material 13 exceeds 20%, the influence due to the variation of the protruding amount becomes large. For this reason, it is difficult to average and supply the gas flow rate. Here, out of the total pressure loss of the gas flow path, when the pressure loss of the gas flow path under the flat plate is 30%, the pressure loss P ₀ when the decrease in the flow path cross-sectional area due to the protrusion is 0% is 100. if you did this,
P ₀ = (pressure loss of gas flow path under flat plate) + (pressure loss of gas flow path in other part)
= 30 + 70
= 100
Pressure loss P ₁ when the reduction of the flow path cross-sectional area by the projection of the gas flow passage under a flat plate occurs 20%,
P ₁ ≈ (pressure loss of the gas flow path under the flat plate) + (pressure loss of the gas flow path at the other part)
≈30 × {100 / (100−20)} ² +70
≒ 117
Approximately 17% pressure loss will increase.
Considering the fuel utilization rate and air utilization rate of the fuel cell when the pressure loss increases by 17%,
70% x 1.17 = 82% when the fuel loss is increased by 17%.
Normal air utilization 50% ⇒ If pressure loss increases 17% 50% x 1.17 = 59%
And an error of about 10% occurs. Since the fluctuation of about 10% is a limit value in terms of stable power generation, the protruding amount needs to be suppressed to 20%.

  In FIG. 2A, the fuel gas supplied from the inlet region of each fuel gas channel 6a to the reaction unit is used for the electrochemical reaction in the reaction unit. A part of the fuel gas flows into the outlet side manifold 6j formed in the outlet region of the anode side plate 6 without being reacted, and joins and is discharged to the fuel discharge hole 6l through the fuel lead-out path 6k therebelow. Is done. It is preferable for preventing gas leakage that the flat plate 14 covering the outlet region of each fuel gas flow path 6a, the outlet side manifold 6j, and the fuel outlet path 6k is attached with the same sheet material (not shown) interposed therebetween. A gas rectifying protrusion 6r and a protrusion 6s are also formed on the outlet side manifold 6j and the fuel outlet path 6k, respectively.

  An oxidant supply hole 6m and a cooling water supply hole 6n are formed in the upper part of the anode side plate 6, and an oxidant discharge hole 6p and a cooling water discharge hole 6q are formed in the lower part.

FIG. 2B is a plan view showing the surface on the opposite side of the anode side plate 6, in which the plurality of cooling water flow paths 6 b that circulate the cooling water supplied from the cooling water supply holes 6 n are arranged in parallel. Yes.
And the cooling water which flowed through each cooling water flow path 6b is discharged | emitted by the said cooling water discharge hole 6q.

  5A and 5B are plan views of the cathode side plate 7, wherein FIG. 5A shows the surface side where the oxidant gas flow path 7a is formed, and FIG. 5B shows the opposite plane 7b side. In this figure (a), 15 is a flat plate, the entrance area | region of the oxidant gas flow path 7a, the oxidant introduction path 7d formed in the shape of a concave groove communicating with the oxidant supply hole 7c, and this oxidation The inlet side manifold 7e that is communicated with the outlet of the agent introduction port 7d and the inlets of the plurality of oxidant gas flow paths 7a and that is formed in a concave groove shape can be covered at the same time. A plurality of ridges 7f that regulate the inflow amount of the oxidant gas supplied from the oxidant supply hole 7c are spaced substantially along the oxidant introduction path 7d in the almost first half of the oxidant introduction path 7d. A protrusion 7g that is arranged in parallel with each other and distributes the oxidant gas flowing into the inlet side manifold 7e from the oxidant introduction passage 7d to the inlets of the respective oxidant gas flow paths 7a at the substantially central portion of the inlet side manifold 7e. Is provided.

  The flat plate 15 is made of a thin metal plate or resin plate similar to the flat plates 12 and 14, and although not shown, double-sided adhesive as a sealing means is attached to a recess provided in the cathode side plate 7 corresponding to the shape of the flat plate 15. A sheet material 13 made of a sheet is interposed and attached by an adhesive means. At this time, the upper surface of the flat plate 15 is flush with the upper surface of the cathode side plate 7.

  Similarly to the above, the lower surface side of the sheet material 13 is brought into close contact with the upper surface of the rib located between the oxidant gas flow paths 7a, and in close contact with the bottom and side surfaces of the outer peripheral portion of the recess. Thereby, it is possible to prevent the oxidant gas passing through the inlet region of each oxidant gas flow path 7a from leaking into the adjacent oxidant gas flow path 7a under the flat plate.

  Also in this case, the portion facing the oxidant gas flow paths 7a on the lower surface side of the sheet material 13 protrudes substantially uniformly into the oxidant gas flow paths 7a by moderate pressurization during bonding. When the pressure loss of the gas flow path under the flat plate is within 30% of the total pressure loss of the gas flow path, the protruding amount of the sheet material 13 is 20% of the cross-sectional area of the oxidant gas flow path 7a. Keep it below. When the protruding amount of the sheet material 13 exceeds 20%, the influence due to the variation in the protruding amount becomes large, so that it becomes difficult to average and supply the gas flow rate.

  In FIG. 5A, the oxidant gas supplied from the inlet region of each oxidant gas flow path 7a to the reaction part is used for an electrochemical reaction in the reaction part. A part of the oxidant gas flows into an outlet side manifold 7h formed in the outlet region of the cathode side plate 7 without being reacted, and merges and passes through the oxidant outlet passage 7i below to oxidant discharge holes. 7j is discharged. It is preferable for preventing gas leakage that the flat plate 16 covering the outlet region of each oxidant gas flow path 7a, the outlet side manifold 7h, and the oxidant outlet path 7i is attached with the same sheet material 13 interposed therebetween.

  Further, a fuel supply hole 7k and a cooling water supply hole 7l are formed in the upper part of the cathode side plate 7, and these positions are respectively located in the fuel supply hole 6c and the cooling water supply hole 6n of the anode side plate 6. A fuel discharge hole 7m and a cooling water discharge 7n are formed in the lower part, and these positions correspond to the fuel discharge hole 6l and the cooling water discharge hole 6q of the anode side plate 6, respectively. Yes.

  FIG. 5B is a plan view showing an opposite surface of the cathode side plate 7, and this surface is formed on the plane 7 b and is the surface of the cooling water flow path 8 a of the first cooling plate 8 or the anode side plate 6. The surface of the cooling water channel 6b is in contact.

  As described above, both surfaces of the second cooling plate 9 are formed on the flat surfaces 9a and 9b, and the surface of the cooling water flow path 6b of the anode side plate 3 is in contact with one flat surface 9a. Although not shown, each of the first cooling plate 8 and the second cooling plate 9 includes a fuel supply hole, a fuel discharge hole, an oxidant supply hole, an oxidant discharge hole, a cooling water supply hole, and a cooling. Water discharge holes are formed at positions corresponding to the holes of the anode side plate 3 and the cathode side plate 7, respectively. These holes are also formed in the first fastening plate 10 and the second fastening plate 11 in the same manner. Thus, when the battery stack is formed, the fuel supply hole, the fuel discharge hole, the oxidant supply hole, the oxidant discharge hole, the cooling water supply hole, and the cooling water discharge hole are respectively provided in the battery stack. A tunnel-like flow hole is formed by connecting in the stacking direction.

  When the battery stack is configured, the gas is interposed between the plates so that the reaction gas and the cooling water do not leak out of the battery stack. 6A and 6B show an example of the gasket. FIG. 6A shows the gasket 17 interposed on the surface of the fuel gas flow path 6a of the anode side plate 6, and FIG. 6B shows the surface of the cooling water flow path 6b of the anode side plate 6. FIG. The gasket 18 interposed in the side is shown.

  The gasket 17 includes a fuel supply hole 6c, outer peripheral contour portions of the flat plates 12 and 14, a fuel gas flow path 6a, a fuel discharge hole 61, an oxidant supply hole 6m, an oxidant discharge hole 6p, and a cooling water supply hole. 6n is provided so as to surround each of the cooling water discharge holes 6q. In addition, since a plurality of horizontal line portions 17a and 17b are provided on the upper surfaces of the flat plates 12 and 14, the flat plates 12 and 14 are pressed by these horizontal line portions 17a and 17b. Thereby, the clamping holding force with respect to the thin flat plates 12 and 14 can be maintained. Gas leakage to the adjacent gas flow path under the flat plate 12 can be prevented by the double-sided adhesive sheet and the horizontal line portions 17a that are a plurality of linear gaskets having a pressing area equal to or smaller than the gas flow path area under the flat plate 12. .

  The gasket 18 includes a cooling water supply hole 6n, a cooling water introduction path, a cooling water flow path 6b, a cooling water outlet side manifold, a cooling water discharge hole 6q, a fuel supply hole 6c, a fuel discharge hole 6l, and an oxidant. The supply hole 6m and the oxidant discharge hole 6p are provided so as to surround them.

  The gaskets 17 and 18 are preferably bonded to the surface of the anode side plate 6 in advance so as not to be displaced when the battery stack is tightened. Among them, the gasket 18 is not bonded to the surface of the cooling water flow path 6b of the anode side plate 6, but the flat surface 7b of the anode side plate 7 contacting the surface of the cooling water flow path 6b as shown in FIG. You may make it adhere | attach to the plane 9a side of the 2nd cooling plate 9. FIG. Moreover, as shown in FIG. 1, it is preferable to interpose the seal material 19 of a protrusion along the outer peripheral edge part of each plate between each plate.

  The plate for a fuel cell according to the present invention is configured as described above. A reactive gas is supplied to a battery stack including these plates, and an electrochemical reaction occurs in each single cell 1 to generate electric power. DC power can be taken out from the current collecting plate 10 a of the attached plate 10 and the current collecting plate 11 a of the second fastening plate 11. That is, the reaction gas supplied to the battery stack is distributed and supplied to each single cell 1, the fuel gas flows through the fuel gas flow path 6 a of the anode side plate 6, and the oxidant gas is the oxidant of the cathode side plate 7. Electricity is generated by an electrochemical reaction through the gas passage 7a and through the polymer electrolyte membrane 2. In addition, cooling water is supplied to the battery stack to suppress an increase in the temperature of the battery stack accompanying power generation, thereby maintaining the battery stack at an appropriate temperature.

  In this power generation, the fuel gas inlet region of the anode side plate 6 is formed into a tunnel shape by attaching the sheet material 13 and the flat plate 12 as described above, and the sheet material 13 is a rib positioned between the fuel gas flow paths 6a. Since it is firmly fixed to the upper surface of 6i, no gas leaks into the adjacent fuel gas flow path 6a. Thereby, the fuel gas quantity which flows through each fuel gas flow path 6a can be averaged. Further, since the fuel gas inlet region is formed with a narrow opening cross-sectional area of the fuel gas flow path 6a, the flow of the fuel gas is accelerated by the nozzle function. As a result, the supply of the fuel gas from the fuel gas inlet region can flow almost uniformly and smoothly to the reaction section.

  Similarly, the oxidant gas inlet region of the cathode side plate 7 is formed in a tunnel shape by attaching the sheet material 13 and the flat plate 15, and the sheet material is formed on the upper surface of the rib located between the oxidant gas flow paths 7a. Since they are tightly fixed, no gas leaks into the adjacent oxidant gas flow path 7a. Thereby, the amount of oxidant gas flowing through each oxidant gas flow path 7a can be averaged. Moreover, since the opening cross-sectional area of the oxidant gas flow path 7a is formed narrow in the oxidant gas inlet region, the flow of the oxidant gas is accelerated by the nozzle function. As a result, the supply of the oxidant gas from the oxidant gas inlet region can flow almost uniformly and smoothly to the reaction section.

  In this way, since the fuel gas and the oxidant gas are uniformly and smoothly supplied to the reaction section in each single cell 1, it is possible to suppress a decrease in power generation performance.

  INDUSTRIAL APPLICABILITY The present invention can be applied to a fuel cell plate, and a fuel cell excellent in power generation performance can be provided by configuring a fuel cell stack using the fuel cell plate.

1 is a schematic exploded cross-sectional view showing a configuration of a fuel cell stack, in which three single cells are stacked. 1 is a plan view of an anode side plate showing an embodiment of a fuel cell plate according to the present invention, wherein (a) is a surface side where a fuel gas flow path is formed, and (b) is a cooling water flow path formed. Each side is shown. (A) is a schematic plan view which expands and shows the fuel gas inlet_port | entrance area | region in FIG. 2, (b) is a schematic sectional drawing along the AA line. (A) is a schematic sectional drawing which shows the state before adhering a sealing material, (b) is a schematic sectional drawing which shows the state after adhering a sealing material with a flat plate. It is a top view of the cathode side plate which shows embodiment of the plate for fuel cells which concerns on this invention, (a) is the surface side in which the oxidant gas flow path is formed, (b) is the opposite plane side, respectively. Show. It is a top view which shows an example of the gasket interposed between plates, (a) is a gasket interposed in the fuel gas flow-path surface side of an anode side plate, (b) is interposed in the cooling water flow-path surface side of an anode side plate. The gasket is shown. It is a top view which shows the other example of the gasket interposed between plates.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Single cell 2 Polymer electrolyte membrane 3 Anode electrode 4 Cathode electrode 5 Membrane electrode assembly 6 Anode side plate 6a Fuel gas flow path 6b Cooling water flow path 7 Cathode side plate 7a Oxidant gas flow path 7b Plane 8 1st cooling plate 8a Cooling water flow path 8b Plane 9 Second cooling plate 10 First fastening plate 10a Current collecting plate 11 Second fastening plate 11a Current collecting plates 12, 14, 15, 16 Flat plate 13 Sheet material 17, 18 Gasket 19 Sealing material

Claims (4)

  In a plate for a fuel cell in which a flat plate is attached to the end of a plurality of gas flow paths arranged in parallel to form a tunnel-shaped gas flow path, between the flat plate and the gas flow path region covered by the flat plate. A fuel cell plate characterized in that a sealing means is interposed, and gas leakage to the adjacent gas flow path under the flat plate of the reaction gas flowing through each gas flow path is prevented by the sealing means.   2. The fuel cell plate according to claim 1, wherein the sealing means is made of a sheet material, and the sheet material is closely attached to the upper surface of each rib located between the flat plate and the gas flow path.   The sheet material is a rubber mainly composed of a styrene-isoprene-styrene (SIS) copolymer, a styrene-butadiene-styrene (SBS) copolymer, a styrene-butylene-ethylene-styrene (SEBS) copolymer, Alternatively, it is a double-sided adhesive sheet made of a material mainly composed of ethylene-propylene-diene rubber (EPDM), hydrogenated acrylonitrile-butadiene rubber (HNBR), silicon rubber, fluorine rubber, etc., and a tackifier. The fuel cell plate according to claim 2.   When the pressure loss of the gas flow path under the flat plate is less than 30% of the total pressure loss of the gas flow path, the reduction of the flow path cross-sectional area due to the protrusion of the sheet material to each gas flow path is 4. The fuel cell plate according to claim 2, wherein the plate is suppressed to 20% or less of a road cross-sectional area.

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