JP2011175880A - Fuel cell - Google Patents

Abstract

A power generation region of a separator can be provided efficiently and can be made compact in size.
A fuel cell includes an electrolyte membrane / electrode structure, a first metal separator, and a second metal separator. A plurality of oxidant gas supply communication holes 18a for supplying an oxidant gas and communicating with each other in the direction of arrow A are connected to the upper edge of the long side direction of the fuel cell 10 and the oxidant gas supply communication holes 18a. In addition, a plurality of fuel gas supply communication holes 20a that are located inward of the separator surface and communicate with each other in the direction of arrow A to supply fuel gas are arranged in the direction of arrow B. Each fuel gas supply communication hole 20a is disposed below each oxidant gas supply communication hole 18a.
[Selection] Figure 1

Description

  The present invention relates to a fuel cell in which an electrolyte / electrode structure provided with a pair of electrodes on both sides of an electrolyte is sandwiched between a pair of rectangular separators.

  For example, in a polymer electrolyte fuel cell, an electrolyte membrane / electrode structure (MEA) in which an anode side electrode and a cathode side electrode are disposed on both sides of an electrolyte membrane made of a polymer ion exchange membrane is provided by a pair of separators. The unit cell is sandwiched. This type of fuel cell is usually used as an in-vehicle fuel cell stack, for example, by stacking a predetermined number of unit cells.

  In the above fuel cell, a fuel gas flow channel for flowing fuel gas is provided in the plane of one separator so as to face the anode side electrode, and the cathode side electrode is opposed in the plane of the other separator. An oxidant gas flow path for flowing an oxidant gas is provided. Further, a cooling medium flow path for flowing a cooling medium is formed between the separators constituting each fuel cell and adjacent to each other.

  Further, the separator is formed with a fuel gas communication hole through which fuel gas passes through in the stacking direction of the fuel cell, an oxidant gas communication hole through which oxidant gas flows, and a cooling medium communication hole through which a cooling medium flows. An internal manifold type fuel cell separator may be configured.

  In this case, for example, the flow direction of the fuel gas flow path and the flow direction of the oxidant gas flow path are set to be parallel flows in the same direction parallel to each other or counterflows in opposite directions. In this case, the fuel gas is uniformly supplied from the fuel gas communication hole on the supply side to the entire area of the fuel gas flow path, while the oxidant gas is uniformly supplied to the entire area of the oxidant gas flow path from the oxidant gas communication hole on the supply side. It is necessary.

  Therefore, for example, the fuel cell disclosed in Patent Document 1 includes a hydrogen-side separator 1 as shown in FIG. In the power generation region of the separator 1, an uneven hydrogen gas channel 2 is formed by press molding, and a cooling water channel 3 is formed on the back side of the hydrogen gas channel 2.

  On one side of the separator 1, a hydrogen manifold hole 4, a cooling water manifold hole 5, and an air manifold hole 6 are provided penetrating in the stacking direction. The hydrogen manifold hole 4 and the hydrogen gas flow path 2 communicate with each other via a hydrogen gas distribution flow path 7, and the hydrogen gas distribution flow path 7 is provided with a fluid rectifying rib 8 at a substantially central portion.

Japanese Patent Laid-Open No. 2006-32008

  However, in the separator 1 described above, in order to supply hydrogen gas uniformly from the hydrogen manifold hole 4 over the entire region in the width direction of the hydrogen gas flow path 2, the separator 1 extends in the longitudinal direction (arrow L direction). A hydrogen gas distribution channel 7 is provided.

  For this reason, the power generation region of the separator 1 cannot be efficiently provided in the plane of the separator 1. Thereby, when it is going to raise electric power generation capability, there exists a problem that the separator 1 becomes long quite easily and the whole fuel cell enlarges.

  The present invention solves this type of problem, and an object of the present invention is to provide a fuel cell that can efficiently provide a power generation region of a separator and that can be favorably downsized.

  In the present invention, an electrolyte / electrode structure in which a pair of electrodes is provided on both sides of an electrolyte is sandwiched between a pair of rectangular separators, and a fuel gas channel through which fuel gas is circulated on one of the surfaces of the separator Is formed on the surface of the other separator, and a cooling medium flow path for flowing a cooling medium is formed between the separators adjacent to each other. The present invention relates to a fuel cell.

  In the fuel cell, in the vicinity of at least one side of the separator, a first fluid communication hole through which a first fluid that is one fluid of a fuel gas, an oxidant gas, or a cooling medium flows in the stacking direction; There are provided a plurality of second fluid communication holes that are located inward of the separator surface with respect to the fluid communication holes and through which a second fluid, which is another fluid different from the first fluid, flows in the stacking direction. Yes.

  Moreover, it is preferable that the separator surface which distribute | circulates a 1st fluid to a surface direction is provided with the seal | sticker part which goes around for every 2nd fluid communication hole.

  Furthermore, the second fluid communication hole is preferably a fuel gas communication hole.

  According to the present invention, the first fluid communication holes and the second fluid communication holes are arranged in two rows on one side of the separator inward in the separator surface direction, and the second fluid communication holes are A plurality are provided. For this reason, the first fluid supplied from the first fluid communication hole to the first fluid flow path passes between the plurality of second fluid communication holes, that is, the second fluid communication hole is used as a buffer portion. , And is distributed well in the width direction of the first fluid flow path. On the other hand, since a plurality of second fluid communication holes are provided, the second fluid is well distributed from each second fluid communication hole in the width direction of the second fluid flow path.

  As a result, a dedicated buffer unit is not required, the power generation region can be efficiently expanded, and the output can be improved satisfactorily. In addition, since the distribution of the first and second fluids is improved, the power generation performance is stabilized, and the entire fuel cell can be easily made compact.

It is a principal part disassembled perspective explanatory drawing of the fuel cell which concerns on the 1st Embodiment of this invention. FIG. 2 is a sectional view of the fuel cell taken along line II-II in FIG. 1. It is front explanatory drawing of the 1st metal separator which comprises the said fuel cell. It is one front explanatory drawing of the 2nd metal separator which comprises the said fuel cell. It is the other front explanatory drawing of the said 2nd metal separator. It is a principal part disassembled perspective explanatory drawing of the fuel cell which concerns on the 2nd Embodiment of this invention. It is front explanatory drawing of the 1st metal separator which comprises the said fuel cell. It is one front explanatory drawing of the 2nd metal separator which comprises the said fuel cell. It is the other front explanatory drawing of the said 2nd metal separator. It is a principal part disassembled perspective explanatory drawing of the fuel cell which concerns on the 3rd Embodiment of this invention. It is front explanatory drawing of the 1st metal separator which comprises the said fuel cell. It is one front explanatory drawing of the 2nd metal separator which comprises the said fuel cell. It is the other front explanatory drawing of the said 2nd metal separator. It is explanatory drawing of the separator which comprises the fuel cell currently disclosed by patent document 1. FIG.

  As shown in FIGS. 1 and 2, the fuel cell 10 according to the first embodiment of the present invention includes an electrolyte membrane / electrode structure 12 and a first metal separator that sandwiches the electrolyte membrane / electrode structure 12 ( A cathode separator) 14 and a second metal separator (anode separator) 16. A plurality of fuel cells 10 are usually stacked in the direction of arrow A to form a fuel cell stack.

  The first metal separator 14 and the second metal separator 16 are made of, for example, a steel plate, a stainless steel plate, an aluminum plate, a plated steel plate, or a metal plate whose surface has been subjected to anticorrosion treatment. The first metal separator 14 and the second metal separator 16 have a vertically long shape with a rectangular plane, and are formed into a concavo-convex shape by pressing a metal thin plate into a wave shape.

  As shown in FIG. 1, the upper end edge (upper short side) (one side) of the fuel cell 10 in the long side direction (arrow C direction) communicates with each other in the arrow A direction, 1 fluid), for example, a plurality of oxidant gas supply communication holes (first fluid communication holes) 18a for supplying oxygen-containing gas are arranged in the arrow B direction.

  The fuel cell 10 is located at the upper edge of the fuel cell 10 inward of the separator surface with respect to the oxidant gas supply communication hole 18a (downward in FIG. 1), and communicates with each other in the direction of the arrow A. ), For example, a plurality of fuel gas supply communication holes (second fluid communication holes) 20a for supplying the hydrogen-containing gas are arranged in the arrow B direction.

  The fuel gas supply communication hole 20a is disposed below the oxidant gas supply communication hole 18a, and the opening area of each fuel gas supply communication hole 20a is smaller than the opening area of each oxidant gas supply communication hole 18a. The number Na of the fuel gas supply communication holes 20a and the number Nc of the oxidant gas supply communication holes 18a are preferably set to Na / Nc> 1.

  A plurality of oxidant gas discharge communication holes 18b for communicating with each other in the direction of the arrow A to discharge the oxidant gas are provided at the lower edge (lower side short side) in the long side direction of the fuel cell 10 as shown by the arrow B. Arranged in the direction. The lower end edge of the fuel cell 10 in the long side direction is located inward of the separator surface direction (upward in FIG. 1) from the oxidant gas discharge communication hole 18b and communicates with each other in the direction of arrow A to A plurality of fuel gas discharge communication holes 20b are provided in the direction of arrow B.

  The oxidant gas discharge communication hole 18b and the fuel gas discharge communication hole 20b are configured in the same manner as the oxidant gas supply communication hole 18a and the fuel gas supply communication hole 20a, and a detailed description thereof will be omitted. The oxidant gas supply communication hole 18a and the oxidant gas discharge communication hole 18b may each be one.

  A plurality of cooling medium supply communication holes 22a for communicating with each other in the direction of arrow A and for supplying a cooling medium are provided above both end edges (long sides) in the short side direction (arrow B direction) of the fuel cell 10. It is done. A plurality of cooling medium discharge communication holes 22 b for discharging the cooling medium are provided below both edge portions in the short side direction of the fuel cell 10.

  The electrolyte membrane / electrode structure 12 includes, for example, a solid polymer electrolyte membrane 24 in which a perfluorosulfonic acid thin film is impregnated with water, and a cathode side electrode 26 and an anode side electrode 28 that sandwich the solid polymer electrolyte membrane 24. With.

  The cathode side electrode 26 and the anode side electrode 28 are uniformly coated on the surface of the gas diffusion layer with a gas diffusion layer (not shown) made of carbon paper or the like, and porous carbon particles carrying a platinum alloy on the surface. And an electrode catalyst layer (not shown) formed. The electrode catalyst layers are formed on both surfaces of the solid polymer electrolyte membrane 24.

  As shown in FIGS. 1 and 3, the surface 14a of the first metal separator 14 facing the electrolyte membrane / electrode structure 12 is oxidized through an oxidant gas supply communication hole 18a and an oxidant gas discharge communication hole 18b. The agent gas flow path 30 is formed. The oxidant gas flow path 30 is formed between a plurality of wavy convex portions 30a extending in the direction of arrow C.

  As shown in FIG. 4, on the surface 16a of the second metal separator 16 facing the electrolyte membrane / electrode structure 12, there is a fuel gas flow path 32 that connects the fuel gas supply communication hole 20a and the fuel gas discharge communication hole 20b. It is formed. The fuel gas flow path 32 is formed between a plurality of wavy convex portions 32a extending in the direction of arrow C.

  Between the surface 16b of the second metal separator 16 and the surface 14b of the first metal separator 14, there is a cooling medium flow path 34 communicating with the cooling medium supply communication holes 22a and 22a and the cooling medium discharge communication holes 22b and 22b. Formed (see FIG. 1 and FIG. 5). The cooling medium flow path 34 circulates the cooling medium over the electrode range of the electrolyte membrane / electrode structure 12.

  A first seal member 36 is integrally formed on the surfaces 14 a and 14 b of the first metal separator 14 around the outer peripheral edge of the first metal separator 14. A second seal member 38 is integrally formed on the surfaces 16 a and 16 b of the second metal separator 16 around the outer peripheral edge of the second metal separator 16. As the first seal member 36 and the second seal member 38, for example, EPDM, NBR, fluorine rubber, silicone rubber, fluorosilicone rubber, butyl rubber, natural rubber, styrene rubber, chloroprene or acrylic rubber or the like, cushion material Or a packing material is used.

  As shown in FIG. 3, the surface 14a of the first metal separator 14 has a plurality of inlet connections in which the first seal member 36 is notched and the oxidant gas supply communication hole 18a and the oxidant gas flow path 30 communicate with each other. A passage 40a is formed. A plurality of outlet connection passages 40 b that communicate with the oxidant gas discharge communication hole 18 b and the oxidant gas flow path 30 are formed in the surface 14 a by cutting out the first seal member 36.

  The first seal member 36 includes, on the surface 14a, a seal portion 36a that circulates for each fuel gas supply communication hole 20a and a seal portion 36b that circulates for each fuel gas discharge communication hole 20b.

  As shown in FIG. 4, a plurality of inlet connection passages 42 a that cut the second seal member 38 in the surface 16 a of the second metal separator 16 and communicate the fuel gas supply communication hole 20 a and the fuel gas flow path 32. Is formed. A plurality of outlet connection passages 42 b that communicate the fuel gas discharge communication hole 20 b and the fuel gas flow path 32 are formed in the surface 16 a by cutting out the second seal member 38.

  As shown in FIG. 5, a second seal member 38 is notched on the surface 16 b of the second metal separator 16, and a plurality of left and right cooling medium supply communication holes 22 a, 22 a and the cooling medium flow path 34 communicate with each other. The inlet connection passage 44a is formed. The surface 16b is formed with a plurality of outlet connection passages 44b that cut out the second seal member 38 to communicate the left and right cooling medium discharge communication holes 22b, 22b with the cooling medium flow path 34.

  The operation of the fuel cell 10 configured as described above will be described below.

  First, as shown in FIG. 1, an oxidant gas such as an oxygen-containing gas is supplied to each oxidant gas supply communication hole 18a, and a fuel such as a hydrogen-containing gas is supplied to each fuel gas supply communication hole 20a. Gas is supplied. Furthermore, a cooling medium such as pure water, ethylene glycol, or oil is supplied to each cooling medium supply communication hole 22a.

  For this reason, the oxidant gas is introduced into the oxidant gas flow path 30 of the first metal separator 14 from the oxidant gas supply communication hole 18a. As shown in FIG. 3, the oxidant gas moves in the direction of arrow C (the direction of gravity) along the oxidant gas flow path 30 and is supplied to the cathode side electrode 26 of the electrolyte membrane / electrode structure 12.

  On the other hand, the fuel gas is supplied to the fuel gas flow path 32 of the second metal separator 16 from the fuel gas supply communication hole 20a. As shown in FIG. 4, the fuel gas moves in the gravity direction (arrow C direction) along the fuel gas flow path 32 and is supplied to the anode side electrode 28 of the electrolyte membrane / electrode structure 12.

  Therefore, as shown in FIG. 1, in the electrolyte membrane / electrode structure 12, the oxidant gas supplied to the cathode side electrode 26 and the fuel gas supplied to the anode side electrode 28 are electrically connected in the electrode catalyst layer. It is consumed by chemical reaction to generate electricity.

  Next, the oxidant gas supplied to and consumed by the cathode side electrode 26 of the electrolyte membrane / electrode structure 12 is discharged in the direction of arrow A along the oxidant gas discharge communication hole 18b. On the other hand, the fuel gas supplied to and consumed by the anode side electrode 28 of the electrolyte membrane / electrode structure 12 is discharged in the direction of arrow A along the fuel gas discharge communication hole 20b.

  The cooling medium supplied to each cooling medium supply communication hole 22a is introduced into the cooling medium flow path 34 between the first metal separator 14 and the second metal separator 16, as shown in FIG. As shown in FIG. 5, the cooling medium once flows in the direction of arrow B (horizontal direction) and then moves in the direction of arrow C (gravity direction) to cool the electrolyte membrane / electrode structure 12. This cooling medium moves outward in the direction of arrow B, and is then discharged to each cooling medium discharge communication hole 22b.

  In this case, in the first embodiment, the surface 14a of the first metal separator 14 has a plurality of oxidant gas supply communication holes 18a in the direction of the arrow B at the upper edge in the long side direction, as shown in FIG. A plurality of fuel gas supply communication holes 20a are arranged in the arrow B direction below the oxidant gas supply communication holes 18a (inward in the separator surface direction).

  Each fuel gas supply communication hole 20a has a considerably smaller opening area than each oxidant gas supply communication hole 18a. Further, the number Na of the fuel gas supply communication holes 20a is set to be larger than the number Nc of the oxidant gas supply communication holes 18a (Na / Nc ≧ 2). In the surface 14a, the first seal member 36 is notched to form a plurality of inlet connection passages 40a that connect the oxidant gas supply communication holes 18a and the oxidant gas flow paths 30, while each fuel gas A seal portion 36a that goes around for each supply communication hole 20a is provided.

  Therefore, the oxidant gas supplied to each oxidant gas supply communication hole 18a circulates through each inlet connection passage 40a to the oxidant gas flow path 30 and circulates for each fuel gas supply communication hole 20a. The seal part 36a functions as a buffer part. Therefore, the oxidant gas is distributed in a good and uniform manner in the width direction (arrow B direction) of the oxidant gas flow channel 30, and the oxidant gas is uniformly supplied over the entire power generation region of the oxidant gas flow channel 30. The effect of being carried out is obtained.

  On the other hand, more fuel gas supply communication holes 20a are arranged along the direction of arrow B than the oxidant gas supply communication holes 18a. As a result, as shown in FIG. 4, a plurality of inlet connection passages 42 a communicating each fuel gas supply communication hole 20 a and the fuel gas passage 32 are arranged along the width direction of the fuel gas passage 32. ing. For this reason, the fuel gas supplied to each fuel gas supply communication hole 20a is supplied uniformly and satisfactorily in the width direction of the fuel gas flow channel 32 via each inlet connection passage 42a. A uniform supply of fuel gas is performed over the entire region.

  Therefore, in the first embodiment, dedicated buffer portions for the oxidant gas and the fuel gas are not required, the power generation region can be efficiently expanded, and the output can be improved favorably. . In addition, since the distribution of the fuel gas and the oxidant gas is improved, the power generation performance is stabilized, and the entire fuel cell 10 can be easily made compact.

  Furthermore, in the first embodiment, each fuel gas supply communication hole 20a is arranged on the inner side (power generation region side) in the separator surface direction than each oxidant gas supply communication hole 18a. For this reason, when the impact from the outside is given to the fuel cell 10, the sealing performance of the fuel gas supply communication hole 20a can be maintained well.

  The oxidant gas discharge communication hole 18b and the fuel gas discharge communication hole 20b can achieve the same effects as the oxidant gas supply communication hole 18a and the fuel gas supply communication hole 20a.

  FIG. 6 is an exploded perspective view of a main part of a fuel cell 50 according to the second embodiment of the present invention.

  The same components as those of the fuel cell 10 according to the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. Similarly, in the third embodiment described below, detailed description thereof is omitted.

  The fuel cell 50 includes an electrolyte membrane / electrode structure 52, and a first carbon separator (cathode side separator) 54 and a second carbon separator (anode side separator) 56 that sandwich the electrolyte membrane / electrode structure 52. A metal separator may be used instead of the first and second carbon separators 54 and 56.

  A plurality of oxidant gas supply communication holes 18a are arranged in the arrow B direction at the upper edge of the long side direction of the fuel cell 50 so as to communicate with each other in the arrow A direction. A plurality of cooling medium supply communication holes 22a are arranged in the direction of arrow B so as to be located inward of the separator surface with respect to the oxidizing gas supply communication hole 18a and communicate with each other in the direction of arrow A. A plurality of fuel gas supply communication holes 20a are arranged in the direction of arrow B so as to be located inward of the cooling medium supply communication hole 22a in the separator surface direction and communicate with each other in the direction of arrow A.

  The opening area of each cooling medium supply communication hole 22a is smaller than the opening area of each oxidant gas supply communication hole 18a, and the opening area of each fuel gas supply communication hole 20a is the opening area of each cooling medium supply communication hole 22a. Smaller than. The oxidant gas supply communication hole 18a, the cooling medium supply communication hole 22a, and the fuel gas supply communication hole 20a have the same dimension in the arrow C direction, but have different dimensions in the arrow B direction. The number Nc of the oxidant gas supply communication holes 18a, the number Nw of the cooling medium supply communication holes 22a, and the number Na of the fuel gas supply communication holes 20a are set to Nw / Nc> 1 and Na / Nw> 1. l is preferred.

  As shown in FIGS. 7 to 9, two cooling medium supply communication holes 22a are disposed in the width dimension (the dimension in the direction of arrow B) of one oxidant gas supply communication hole 18a, and Two fuel gas supply communication holes 20a are arranged within the dimension in the width direction of the cooling medium supply communication hole 22a. One fuel gas supply communication hole 20a is disposed between the cooling medium supply communication holes 22a. However, the fuel gas supply communication hole 20a may not be provided at this position.

  As shown in FIG. 7, a predetermined distance S is provided between the positions in the width direction of each oxidant gas supply communication hole 18a and the end position of the cooling medium supply communication hole 22a adjacent to the both positions. It is done.

  A plurality of oxidant gas discharge communication holes 18b, a plurality of cooling medium discharge communication holes 22b, and a plurality of fuel gas discharge communication holes 20b are provided at the lower edge of the long side direction of the fuel cell 50 inward in the separator surface direction (see FIG. 7 are arranged in the direction of the arrow B, in close proximity to each other. The oxidant gas discharge communication hole 18b, the cooling medium discharge communication hole 22b, and the fuel gas discharge communication hole 20b are the same as the oxidant gas supply communication hole 18a, the cooling medium supply communication hole 22a, and the fuel gas supply communication hole 20a. The detailed description thereof is omitted.

  A first seal member 58 is provided individually or integrally on the surface 54a of the first carbon separator 54 on the electrolyte membrane / electrode structure 52 side. As shown in FIG. 8, a second seal member 60 is provided on the surface 56a of the second carbon separator 56 on the electrolyte membrane / electrode structure 52 side, and the surface 56b (56a) of the second carbon separator 56 is provided. A third seal member 62 is provided on the opposite surface (see FIGS. 6 and 9).

  As shown in FIG. 7, a first seal member 58 is notched in the surface 54 a of the first carbon separator 54, and a plurality of inlets communicating the respective oxidant gas supply communication holes 18 a and the oxidant gas flow path 30. A connecting passage 64a, and a plurality of outlet connecting passages 64b that connect each of the oxidizing gas discharge communication holes 18b and the oxidizing gas channel 30 are formed.

  The first seal member 58 includes, on the surface 54a, a seal portion 58a that circulates for each cooling medium supply communication hole 22a, a seal portion 58b that circulates for each fuel gas supply communication hole 20a, and each cooling medium discharge communication hole 22b. A seal portion 58c that circulates every time and a seal portion 58d that circulates for each fuel gas discharge communication hole 20b are provided.

  As shown in FIG. 8, a second seal member 60 is cut out on the surface 56a of the second carbon separator 56 to communicate each fuel gas supply communication hole 20a with the fuel gas flow path 32, while discharging the fuel gas. The communication hole 20b communicates with the fuel gas flow path 32.

  As shown in FIGS. 6 and 9, the surface 56 b of the second carbon separator 56 is notched with a third seal member 62, and a plurality of inlets for communicating the cooling medium supply communication hole 22 a and the cooling medium flow path 34. A connection passage 66a, and a plurality of outlet connection passages 66b that connect the coolant discharge passage 22b and the coolant passage 34 are formed. The third seal member 62 includes, on the surface 56b, a seal portion 62a that circulates for each fuel gas supply communication hole 20a and a seal portion 62b that circulates for each fuel gas discharge communication hole 20b.

  In the second embodiment configured as described above, as shown in FIG. 7, a plurality of oxidant gases are supplied to one side (upper end side) of the first carbon separator 54 inward in the separator surface direction. A communication hole 18a, a cooling medium supply communication hole 22a, and a fuel gas supply communication hole 20a are provided. The number of each of the oxidant gas supply communication hole 18a, the cooling medium supply communication hole 22a, and the fuel gas supply communication hole 20a increases in order, and the fuel gas supply communication hole 20a is connected to the oxidant gas flow path 30. Are provided at equal intervals over the entire width direction.

  Accordingly, the inlet connection passage 64a that connects each oxidant gas supply communication hole 18a and the oxidant gas flow passage 30 includes a seal portion 58a that circulates for each cooling medium supply communication hole 22a, and each fuel gas supply communication hole 20a. The seal portion 58b that circulates every time can serve as a buffer portion.

  For this reason, the oxidant gas introduced into the inlet connection passage 64a from the oxidant gas supply communication hole 18a is dispersed by the plurality of seal portions 58a, and then passes between the plurality of seal portions 58b to flow the oxidant gas flow. It becomes possible to distribute evenly over the entire width direction of the path 30.

  Thereby, in the second embodiment, a dedicated buffer unit is not required, the power generation region can be efficiently expanded, the output can be improved, and the fuel cell 50 as a whole can be made compact. For example, the same effects as those of the first embodiment can be obtained.

  Further, the inlet connection passage 66a that connects the cooling medium supply communication hole 22a and the cooling medium flow path 34 is provided with a seal portion 62a that circulates for each of the many fuel gas supply communication holes 20a (see FIG. 9). . Accordingly, the cooling medium led out from the cooling medium supply communication hole 22a to the inlet connection passage 66a functions as a buffer part in each seal part 62a, and flows through the seal part 62a over the entire width direction of the cooling medium flow path 34. Evenly supplied.

  Furthermore, as shown in FIG. 8, a plurality of fuel gas supply communication holes 20a are provided at predetermined intervals along the width direction of the fuel gas flow path 32. For this reason, the fuel gas introduced from each fuel gas supply communication hole 20a is uniformly introduced over the entire width direction of the fuel gas flow path 32, and the same effect as in the first embodiment can be obtained.

  FIG. 10 is an exploded perspective view of a main part of a fuel cell 70 according to the third embodiment of the present invention.

  The fuel cell 70 includes an electrolyte membrane / electrode structure 72, and a first carbon separator (cathode side separator) 74 and a second carbon separator (anode side separator) 76 that sandwich the electrolyte membrane / electrode structure 72. For example, the first and second carbon separators 74 and 76 may be constituted by metal separators.

  A plurality of oxidant gas supply communication holes 18a, a cooling medium supply communication hole 22a, and a fuel gas supply communication hole 20a are respectively provided in the upper edge of the fuel cell 70 so as to be sequentially close inward in the separator surface direction. The oxidant gas supply communication hole 18a, the cooling medium supply communication hole 22a, and the fuel gas supply communication hole 20a are alternately arranged so that the width dimension in the arrow B direction is the same, and the dimension in the arrow C direction is sequentially shorter. Configured.

  An oxidant gas discharge communication hole 18b, a cooling medium discharge communication hole 22b, and a fuel gas discharge communication hole 20b are provided at the lower end edge of the fuel cell 70 in close proximity to each other inward in the separator surface direction. The oxidant gas discharge communication hole 18b, the cooling medium discharge communication hole 22b, and the fuel gas discharge communication hole 20b are configured in the same manner as the oxidant gas supply communication hole 18a, the cooling medium supply communication hole 22a, and the fuel gas supply communication hole 20a. Therefore, detailed description thereof is omitted.

  A first seal member 78 is provided on a surface 74 a of the first carbon separator 74 facing the electrolyte membrane / electrode structure 72. In the second carbon separator 76, the second seal member 80 is disposed on the surface 76a facing the electrolyte membrane / electrode structure 72, while the third seal member 82 is disposed on the surface 76b (the surface opposite to the surface 76a). Is placed.

  As shown in FIG. 11, the first seal member 78 is notched, and a plurality of inlet connection passages 84a communicating the oxidant gas supply communication hole 18a and the oxidant gas passage 30 on the surface 74a side, and the oxidant gas. A plurality of outlet connection passages 84b are formed to communicate the discharge communication hole 18b and the oxidant gas flow path 30. In the surface 74a, a seal part 78a that circulates for each cooling medium supply communication hole 22a, a seal part 78b that circulates for each fuel gas supply communication hole 20a, a seal part 78c that circulates for each cooling medium discharge communication hole 22b, and each A seal portion 78d that goes around for each fuel gas discharge communication hole 20b is provided.

  As shown in FIG. 12, the second seal member 80 is partly cut out to connect each fuel gas supply communication hole 20 a and each fuel gas discharge communication hole 20 b to the fuel gas flow path 32.

  As shown in FIG. 13, the surface 76 b has a third seal member 82 cut out, and a plurality of inlet connection passages 86 a that connect the cooling medium supply communication hole 22 a and the cooling medium flow path 34, and cooling medium discharge communication. A plurality of outlet connection passages 86b communicating with the holes 22b and the cooling medium flow path 34 are formed. In the surface 76b, the third seal member 80 includes a seal portion 82a that circulates for each fuel gas supply communication hole 20a and a seal portion 82b that circulates for each fuel gas discharge communication hole 20b.

  The third embodiment configured as described above can function in substantially the same manner as the second embodiment. Therefore, the same effects as those of the first and second embodiments can be obtained, such as eliminating the need for a dedicated buffer unit and making the entire fuel cell 70 more compact.

DESCRIPTION OF SYMBOLS 10, 50, 70 ... Fuel cell 12, 52, 72 ... Electrolyte membrane electrode assembly 14, 16 ... Metal separator 18a ... Oxidant gas supply communication hole 18b ... Oxidant gas discharge communication hole 20a ... Fuel gas supply communication hole 20b ... fuel gas discharge communication hole 22a ... cooling medium supply communication hole 22b ... cooling medium discharge communication hole 24 ... solid polymer electrolyte membrane 26 ... cathode side electrode 28 ... anode side electrode 30 ... oxidant gas flow path 32 ... fuel gas flow path 34 ... Cooling medium flow paths 36, 36a, 36b, 38, 58, 58a-58d, 60, 62, 62a, 62b, 78, 78a-78d, 80, 82, 82a, 82b ... Seal members 40a, 42a, 44a, 64a, 66a, 84a, 86a ... Inlet connection passages 40b, 42b, 44b, 64b, 66b, 84b, 86b ... Outlet connection passages 54, 56, 74, 7 ... carbon separator

Claims (3)

An electrolyte / electrode structure provided with a pair of electrodes on both sides of the electrolyte is sandwiched between a pair of rectangular separators, and a fuel gas passage through which fuel gas is circulated is formed on the surface of one of the separators. The other separator is a fuel cell in which an oxidant gas flow path for flowing an oxidant gas is formed on the surface of the other separator, and a cooling medium flow path for flowing a cooling medium is formed between the adjacent separators. And
In the vicinity of at least one side of the separator, a first fluid communication hole through which a first fluid that is one fluid of the fuel gas, the oxidant gas, or the cooling medium flows in the stacking direction;
A plurality of second fluid communication holes that are located inward of the separator surface with respect to the first fluid communication holes and through which a second fluid that is another fluid different from the first fluid flows in the stacking direction;
A fuel cell comprising:   2. The fuel cell according to claim 1, wherein the separator surface through which the first fluid flows in a surface direction is provided with a seal portion that circulates for each second fluid communication hole.   3. The fuel cell according to claim 1, wherein the second fluid communication hole is a fuel gas communication hole.

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