JP2001076751A - Fuel cell system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the piping structures of a first and second fuel cell stacks arranged in parallel with each other and to effectively reduce their height. SOLUTION: Oxidizer gas feeding/exhausting passages 138a, fuel gas feeding/ exhausting passages 138b and cooling medium feeding/exhausting passages 138c are formed symmetrically with each other in a first and second fuel cell stacks 12, 14, and oxidizer gas entrances 120a, fuel gas entrances 122a, oxidizer gas exits 120b and fuel gas exits 122b are so formed on the same vertical surface of the first and second fuel cell stacks 12, 14 as to be positioned on the upper and lower sides at both their lateral ends, and cooling medium feeding ports 216 and cooling medium exhausting ports 132 are so formed as to be positioned in their inwards in the vertical and horizontal directions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a fuel cell comprising a plurality of unit fuel cells, each comprising a solid polymer electrolyte membrane sandwiched between an anode electrode and a cathode electrode, which are horizontally stacked via a separator. The present invention relates to a fuel cell system including a battery stack.

[0002]

2. Description of the Related Art For example, a polymer electrolyte fuel cell is a unit in which an anode electrode and a cathode electrode are opposed to each other on both sides of an electrolyte membrane composed of a polymer ion exchange membrane (cation exchange membrane). The fuel cell is constituted by sandwiching the fuel cell between separators. This polymer electrolyte fuel cell is usually used as a fuel cell stack by stacking a predetermined number of unit fuel cells and separators.

[0003] In this type of fuel cell stack, a fuel gas, for example, hydrogen gas, supplied to an anode electrode is hydrogen-ionized on a catalyst electrode, and is directed to a cathode electrode via an appropriately humidified electrolyte membrane. And move. The electrons generated during that time are taken out to an external circuit and used as DC electric energy. Since an oxidant gas, for example, oxygen gas or air is supplied to the cathode side electrode, the hydrogen ions, the electrons, and the oxygen gas react with each other to generate water at the cathode side electrode.

When the above-described fuel cell stack is mounted on a vehicle or the like and used, a considerably large number of unit fuel cells are required in order to obtain desired power. At this time, if an attempt is made to form a single fuel cell stack by stacking a considerable number of unit fuel cells, the length of the unit fuel cells in the stacking direction becomes considerably long, and fuel gas is transferred to each unit fuel. Problems such as the inability to evenly supply the battery cells occur. In view of this, a fuel cell system in which a plurality of fuel cell stacks are prepared and each fuel cell stack is connected in series via a manifold is employed. For example, in JP-A-8-171926, four stacks (unit fuel cell stacks) are prepared,
Two stacks arranged in two rows in the stacking direction are arranged in series with a fuel supply / discharge member interposed therebetween. The fuel supply / discharge member is provided with holes for supplying / discharging a fuel system or the like to / from the two stacked bodies on opposite vertical surfaces at both ends, and each hole is provided inside the fuel / supply / discharge member. A communicating flow path is formed.

[0005]

In the above-mentioned prior art, two stacks are provided in parallel on both end surfaces of the fuel supply / discharge member, respectively. A pressing mechanism is arranged on the end face opposite to the member to press the laminate in the laminating direction, and an upper case and a lower case are mounted above and below the laminate. For this reason, the assembly operation of the entire fuel cell becomes complicated, the configuration of the fuel supply / discharge member itself becomes considerably complicated, and the fuel supply / discharge member becomes large and complicated, thereby increasing the production cost. It is pointed out.

The present invention solves this kind of problem, in which two fuel cell stacks are arranged in parallel, and a piping structure for supplying and discharging a fluid such as fuel gas to and from each fuel cell stack is simplified. It is an object of the present invention to provide a fuel cell system capable of effectively reducing the height direction of a fuel cell stack.

[0007]

In a fuel cell system according to a first aspect of the present invention, a fuel gas supply / discharge path and an oxidant gas supply / discharge are respectively provided in first and second fuel cell stacks arranged in parallel with each other. The passage and the cooling medium supply / discharge passage are provided symmetrically with each other, and the fuel gas is located symmetrically with respect to the other end vertical surfaces adjacent to each other of the first and second fuel cell stacks. A supply port, a fuel gas discharge port, an oxidant gas supply port, and an oxidant gas discharge port are provided, and a cooling medium supply port and a cooling medium discharge port are provided inwardly and vertically inwardly of these. I have.

As described above, since the supply and discharge passages of the first and second fuel cell stacks are configured symmetrically, the same supply port is provided vertically above and below the mutually adjacent ends. And / or outlets are provided, and the manifold structure for connecting them is easily simplified. In addition, the supply and discharge ports for fuel gas, oxidizing gas, and cooling medium are provided on the same vertical plane, so that pipes can be concentrated on one plane (vertical plane), and workability of pipes is effective. To improve.

Further, the other end vertical surface is provided only with supply and discharge ports for the fuel gas and the oxidizing gas above and below both ends in the horizontal direction, and supply and discharge ports for the cooling medium are provided inside these. I have. Thereby, the height direction of the first and second fuel cell stacks can be effectively shortened, and the space above the first and second fuel cell stacks can be effectively used. It can be used effectively as a battery system.

[0010]

FIG. 1 is a schematic perspective explanatory view of a fuel cell system 10 according to an embodiment of the present invention, and FIG.
FIG. 2 is an explanatory side view of the fuel cell system 10.

The fuel cell system 10 includes a first fuel cell stack 12 and a second fuel cell stack 14 arranged in parallel with each other along the horizontal direction (the direction of arrow A).
First end plates 16, 18 forming one end vertical surfaces on the same side of the first and second fuel cell stacks 12, 14
Is provided with a first power extraction terminal 20 that is a positive electrode and a second power extraction terminal 22 that is a negative electrode.

First and second fuel cell stacks 12, 1
4 is a second end plate 2 which is a vertical surface at the other end on the same side.
A piping mechanism 28 for supplying and discharging a fuel gas, an oxidizing gas and a cooling medium to and from the first and second fuel cell stacks 12 and 14 is incorporated on the sides 4 and 26. The first and second fuel cell stacks 12 and 14 are fixed to a mounting plate 31 constituting a vehicle via a mounting mechanism 30.

As shown in FIGS. 3 and 4, the first fuel cell stack 12 includes a unit fuel cell 32 and first and second separators 34 and 36 sandwiching the unit fuel cell 32. A plurality of these are stacked in the horizontal direction (the direction of arrow A). First fuel cell stack 1
2 has a rectangular parallelepiped shape as a whole, and is arranged with the short side direction (arrow B direction) oriented in the direction of gravity and the long side direction (arrow C direction) oriented in the horizontal direction.

The unit fuel cell 32 has a solid polymer electrolyte membrane 38, a cathode 40 and an anode 42 disposed with the electrolyte membrane 38 interposed therebetween. The anode-side electrode 42 has first and second gas diffusion layers 44 and 46 made of, for example, porous carbon paper as a porous layer.
Is arranged.

On both sides of the unit fuel cell 32, first and second gaskets 48, 50 are provided. The first gasket 48 is large for accommodating the cathode 40 and the first gas diffusion layer 44. While having the opening 52, the second gasket 50 has a large opening 54 for accommodating the anode-side electrode 42 and the second gas diffusion layer 46. Unit fuel cell 32 and first and second units
The gaskets 48, 50 are sandwiched by the first and second separators 34, 36.

The first separator 34 is a cathode-side electrode 4
The surface 34a facing 0 and the surface 34b on the opposite side are set in a rectangular shape. For example, the long side 55a is oriented in the horizontal direction, and the short side 55b is oriented in the direction of gravity.

An oxidizing gas inlet 56a for passing an oxidizing gas, which is oxygen gas or air, and a fuel gas such as a hydrogen gas pass through the first separator 34 on the upper side of both edges on the short side 55b side. And a fuel gas inlet 58a is provided having a vertically long shape. The oxidizing gas outlet 56b and the fuel gas outlet 58b are positioned diagonally below the oxidizing gas inlet 56a and the fuel gas inlet 58a on the lower side of both ends of the first separator 34 on the short side 55b side. It is provided with a long shape in the vertical direction.

At the lower end of the long side 55a of the first separator 34, four cooling medium inlets 60a to 60e long in the direction of arrow C are provided.
60d, and the first separator 34
Similarly, at the upper part on the long side 55a side, four cooling medium outlets 60e to 60h long in the direction of arrow C are provided. A cooling medium such as pure water, ethylene glycol, or oil is supplied to the cooling medium inlets 60a to 60d. On the surface 34a of the first separator 34, ten independent first oxidizing gas flow grooves 62 each communicating with the oxidizing gas inlet 56a.
Are provided in the direction of gravity while meandering in the horizontal direction. The first oxidizing gas channel groove 62 joins the five second oxidizing gas channel grooves 65, and
5 communicates with the oxidant gas outlet 56b. The first separator 34 has six holes 63 for tie rod insertion.

The second separator 36 is formed in a rectangular shape, and an oxidant gas inlet 66a and a fuel gas inlet 68a are formed through the upper portion of both ends on the short side 64b side of the second separator 36. The oxidizing gas outlet 66b and the fuel gas outlet 6
8b is formed so as to penetrate so as to be diagonal to the oxidizing gas inlet 66a and the fuel gas inlet 68a.

In the lower portion of the second separator 36 on the long side 64a side, four cooling medium inlets 70a to 70e long in the direction of arrow C are provided.
70d is formed to penetrate, and at the upper part on the long side 64a side,
Similarly, the cooling medium outlets 70 e to 70 h are formed to extend in a long direction in the arrow C direction.

As shown in FIG. 5, ten first fuel gas flow grooves 72 are formed on the surface 36a of the second separator 36 so as to communicate with the fuel gas inlet 68a. The first fuel gas passage groove 72 joins the five second fuel gas passage grooves 73, and the second fuel gas passage groove 73 is connected to the fuel gas outlet 68b.
Communicate with

As shown in FIG. 6, a cooling medium inlet 70 is provided on a surface 36b of the second separator 36 opposite to the surface 36a.
Cooling medium passages 74a to 74d individually communicating with the cooling medium outlets 70e to 70h are provided in the direction of gravity. The cooling medium flow paths 74a to 74d
Cooling medium inlets 70a to 70d and cooling medium outlets 70e to 7
Nine first flow passage grooves 76a, 76 communicating with 0h
b, and between the first flow channel grooves 76a and 76b, two second flow channel grooves 78 are provided in parallel with each other in the direction of gravity and at a predetermined interval. Similarly to the first separator 34, the second separator 36 is provided with six tie rod insertion holes 63 at six locations.

As shown in FIG. 7, a terminal plate 80 and a first conductive plate 82 are disposed at both ends in the stacking direction of a predetermined number of unit fuel cells 32. The first terminal plate 80 is
The end plate 16 is laminated, and the first power extraction terminal 20 is mounted on the terminal plate 80.

As shown in FIG. 8, the first power extraction terminal 20 has small diameter screw portions 88 at both ends of a cylindrical large diameter portion 86.
a and 88b. The screw portion 88a passes through the hole 90 formed in the terminal plate 80, and passes through the first separator 34.
Projecting into the oxidizing gas inlet 56a of the
A nut member 92 is screwed into the nut. A sealing member 94 is interposed at the shoulder of the large diameter portion 86 in order to improve the sealing property between the large diameter portion 86 and the terminal plate 80, and is formed on the outer periphery of the large diameter portion 86 and the first end plate 16. An insulating ring 98 is interposed between the hole 96 and the hole 96.

As shown in FIG. 9, the first conductive plate 82
Is set to have substantially the same shape as the second separator 36, that is, a rectangular shape. The oxidizing gas inlet 100a, the fuel gas inlet 102a and the oxidizing gas outlet 100b, The outlets 102b are provided at diagonal positions with respect to each other. The lower and upper sides of the long side of the first conductive plate 82 have four cooling medium inlets 1 respectively.
04a to 104d and cooling medium outlets 104e to 104h are provided.
It is formed in the place.

The first conductive plate 82 is provided with a first connection plate portion 106 extending below the first fuel cell stack 12 and adjacent to the second fuel cell stack 14. The first connection plate 106 is provided with two bolts 108a and 108b projecting downward.
The a and 108b and the first conductive plate 82 are made of a material having conductivity, for example, SUS or copper.
As shown in FIG. 7, the second end plate 24 is stacked on the first conductive plate 82 via an insulating plate 110, a cover plate 112, and a seal member 114.

As shown in FIGS. 10 and 11, the second end plate 24 is formed in a rectangular shape, and the oxidizing gas inlet 120a and the fuel gas inlet 122a Is formed through the oxidizing gas outlet 120 at the lower side of both end edges on the short side.
b and the fuel gas outlet 122b are connected to the oxidizing gas inlet 12
0a and the fuel gas inlet 122a.

The inner surface 24a of the second end plate 24
The cooling medium inlets 70 a to 70 of the second separator 36
d, the first cooling medium passage grooves 124a to 124d
And the cooling medium outlets 70 e to 7 of the second separator 36.
0h, the second cooling medium passage grooves 124e to 124h
Are formed to be long in the horizontal direction and have a predetermined depth. The first cooling medium passage grooves 124a to 124d communicate with the ends of the twelve first grooves 126a, respectively. The first groove portions 126a extend upward in parallel with each other, and then merge two by two to form second groove portions 126b, and the second groove portions 126b are each provided with two third groove portions 126c.
And communicates with the cooling medium supply port 128.

Second cooling medium passage grooves 124e to 124h
Similarly communicates with the twelve first grooves 130a, and the first grooves 130a extend vertically
Two lines are merged into the groove 130b. Second groove 130b
Merge into the third groove 130c two by two and communicate with the cooling medium outlet 132. As shown in FIG. 10, a supply pipe 134 and a discharge pipe 136 are connected to the cooling medium supply port 128 and the cooling medium discharge port 132, and the supply pipe 134 and the discharge pipe 136 One fuel cell stack 12 protrudes outward by a predetermined length. Second
The end plate 24 has a hole 63 for tie rod insertion.
Are formed in six places.

In the first fuel cell stack 12, the oxidizing gas inlet 120a of the second end plate 24, the oxidizing gas inlet 56a of the first separator 34, and the oxidizing gas outlet 5
6b and the oxidizing gas supply / discharge passage 138a formed in a U-shape by communicating the oxidizing gas outlet 120b of the second end plate 24, the fuel gas inlet 122a of the second end plate 24, and the second separator 36. Fuel gas inlet 6
8a, the fuel gas outlet 68b and the fuel gas outlet 122b of the second end plate 24 communicate with each other to form a U-shaped fuel gas supply / discharge passage 138b, and the supply conduit 134 of the second end plate 24, Second separator 36
Cooling medium inlets 70a to 70d, cooling medium outlets 70e to 70e
70h and the discharge line 1 of the second end plate 24
36 is a U-shaped cooling medium supply / discharge passage 1 communicating with 36
38c is provided.

As shown in FIGS. 10 and 13, the cooling medium supply port 128 and the cooling medium discharge port 132
0a, fuel gas inlet 122a, oxidant gas outlet 120b
And the fuel gas outlet 122b is provided inwardly in the vertical and horizontal directions.

As shown in FIG. 7, the first fuel cell stack 12 is stacked via the fastening mechanism 140 in the stacking direction (arrow A).
Direction). Tightening mechanism 1
Reference numeral 40 denotes a liquid chamber 142 provided on the outer surface side of the first end plate 16, an incompressible liquid for applying a surface pressure sealed in the liquid chamber 142, for example, a silicon oil 144, and a second end plate 24. And three disc springs 146a to 146c arranged at predetermined intervals in the horizontal direction to press the second end plate 24 toward the first end plate 16 side.
And

A backup plate 148 is provided facing the first end plate 16 with the liquid chamber 142 interposed therebetween. The liquid chamber 142 is formed between the backup plate 148 and the thin plate 150 made of aluminum or stainless steel. Disc springs 146a to 146
“c” are arranged at substantially equal intervals in the plane of the second end plate 24, and are supported by the mounting plate 152. Six tie rods 154 are inserted into the backup plate 148 through the first fuel cell stack 12 from the mounting plate 152. The first fuel cell stack 12 is integrally held by the nut 156 being screwed into the end of the tie rod 154.

As shown in FIGS. 2 and 12, the mounting mechanism 30 includes brackets 160a and 160b integrally provided on the lower side of the first end plate 16;
And mounting brackets 162a and 162b screwed to the lower side of the end plate 24. The first fuel cell stack 12 is attached to the bracket portions 160a and 160b.
Elongate holes 164a, 164a long in the laminating direction (direction of arrow A)
4b, while the mounting bracket 162a,
Holes 166a and 166b are formed in 162b.

The long holes 164a, 164b and the hole 166
A rubber mount 168 is disposed on each of a and 166b. The rubber mount 168 has a screw portion 170
a, 170b are provided, and a collar 172 is disposed on the screw portion 170a projecting upward.
72 is inserted into the long holes 164a and 164b from here, and a nut 174 is screwed into the screw portion 170a. On the side of the mount brackets 162a and 162b, the threaded portion 170a of the rubber mount 168 has the holes 166a and 1b.
The nut 174 is screwed into the end of the nut 66b. Screw part 1 protruding from the lower side of rubber mount 168
70b is inserted into the mounting plate 31 and the nut 1
76 is screwed into the first fuel cell stack 1
2 is fixed to a vehicle or the like.

As shown in FIG. 13, the second fuel cell stack 14 is configured symmetrically to the above-described first fuel cell stack 12 and has a cathode 40 and an anode 42 is disposed on the opposite side, and the second power extraction terminal 22 as a negative electrode is provided on the first end plate 18 side (see FIG. 14). Second
The fuel cell stack 14 is basically configured in the same manner as the first fuel cell stack 12, and the same components are denoted by the same reference characters and will not be described in detail.

As shown in FIG. 15, the second fuel cell stack 14 has a second conductive plate 180, which extends below the second fuel cell stack 14. And the first connection plate 1 of the first conductive plate 82 provided in the first fuel cell stack 12
A second connection plate portion 182 close to 06 is provided. First
The pair of bolt portions 108a, 108b and 184a, 184b are provided on the second connection plate portions 106, 182, respectively.

The bolts 108a and 184a and the bolts 108b and 184b are connected to flexible connectors, for example, stranded wires 186a and 186b, respectively. The stranded wires 186a and 186b are formed by twisting a large number of fine wire wires into a mesh shape, and each of the rubber covers 18
8a and 188b.

As shown in FIG. 13, a fuel gas inlet 122a and an oxidizing gas outlet 120b are close to each other on the second end plates 24 and 26 constituting the first and second fuel cell stacks 12 and 14, respectively. The second end plates 24 and 26 have a piping mechanism 28 incorporated therein.

As shown in FIGS. 1 and 16, the piping mechanism 28 includes second end plates 24, 2 constituting the first and second fuel cell stacks 12, 14 arranged in parallel with each other.
6 is provided with a first bracket 190 which is integrally fixed to the second end plates 24 and 26 so as to cover each fuel gas inlet 122a. The first bracket 190 is provided with fuel gas supply pipes 192a and 192b communicating with the fuel gas inlets 122a, respectively.
92a and 192b join and communicate with the fuel gas supply port 194.

A second bracket 196 is fixed to the second end plates 24 and 26 so as to cover the respective oxidizing gas outlets 120b. The distal ends of the oxidizing gas discharge pipes 198a and 198b provided on the second bracket 196 and communicating with the oxidizing gas outlet 120b are connected to the oxidizing gas outlet 2
00 is integrally communicated.

The second end plates 24 and 26 have respective oxidant gas inlets 120a and fuel gas outlets 12a.
Third and fourth brackets 202, 204 over 2b
Is fixed. Third and fourth brackets 202, 20
4 is connected to both ends of an oxidizing gas supply pipe 206 communicating with the oxidizing gas inlet 120a, and an oxidizing gas supply port 208 is provided on the way of the oxidizing gas supply pipe 206. The third and fourth brackets 202 and 204 have a fuel gas discharge pipe 2 communicating with a fuel gas outlet 122b.
The fuel gas discharge port 212 is provided on the way of the fuel gas discharge pipe 210.

Both ends of a cooling medium supply pipe 214 are connected to respective supply pipes 134 provided in the second end plates 24 and 26, and a cooling medium supply port 216 is provided in the cooling medium supply pipe 214. Second end plates 24, 26
The cooling medium discharge pipe 2 is connected to each discharge pipe 136 provided in
18 and the cooling medium discharge pipe 218
Is provided with a cooling medium outlet 220.

The fuel cell system 1 configured as described above
The operation of 0 will be described below.

As shown in FIG. 1, the fuel cell system 10
Is supplied with a fuel gas (for example, a gas containing hydrogen obtained by reforming a hydrocarbon) from a fuel gas supply port 194 constituting a fuel gas supply / discharge passage 138b, and constitutes an oxidizing gas supply / discharge passage 138a. Air or oxygen gas (hereinafter simply referred to as air) is supplied to the oxidant gas supply port 208 as an oxidant gas. Further, the cooling medium is supplied to the cooling medium supply port 216 that forms the cooling medium supply / discharge path 138c.

The fuel gas supplied to the fuel gas supply port 194 passes through the fuel gas supply pipes 192a and 192b and the first
And the second fuel cell stacks 12 and 14
Each fuel gas inlet 122a of the end plates 24 and 26 is sent to each fuel gas inlet 122a.
8a is introduced into the first fuel gas flow channel groove 72. As shown in FIG. 5, the fuel gas supplied to the first fuel gas channel groove 72 moves in the gravity direction while meandering horizontally along the surface 36 a of the second separator 36.

At this time, the hydrogen gas in the fuel gas is supplied to the anode 42 of the unit fuel cell 32 through the second gas diffusion layer 46. The unused fuel gas is supplied to the anode 42 while moving along the first fuel gas flow channel groove 72, while the unused fuel gas is supplied through the second fuel gas flow channel groove 73. It is discharged from the fuel gas outlet 68b. The unused fuel gas is introduced into the fuel gas discharge pipe 210 through each fuel gas outlet 122b of the second end plates 24 and 26, and is supplied to the fuel gas outlet 212.
Is discharged from the fuel cell system 10 through the

On the other hand, the air supplied to the oxidizing gas supply port 208 is supplied to the respective oxidizing gas inlets 12 provided in the second end plates 24 and 26 through the oxidizing gas supply pipe 206.
0a, and further supplied to an oxidizing gas inlet 56a of the first separator 34 incorporated in the first and second fuel cell stacks 12 and 14 (see FIG. 3). In the first separator 34, the air supplied to the oxidizing gas inlet 56a is introduced into the first oxidizing gas flow groove 62 in the surface 34a, and is horizontally moved along the first oxidizing gas flow groove 62. Move in the direction of gravity while meandering.

At this time, the oxygen gas in the air is supplied from the first gas diffusion layer 44 to the cathode 40 while the unused air is supplied to the oxidizing gas through the second oxidizing gas passage groove 65. It is discharged from the outlet 56b. This oxidant gas outlet 5
The air discharged to the second end plate 24, 2b
6 through the oxidizing gas outlet pipes 198a and 198b from the oxidizing gas outlet 120b provided in the oxidizing gas outlet 2b.
00 (see FIG. 1).

As a result, power is generated in the first and second fuel cell stacks 12 and 14, and a load connected between the first and second power extraction terminals 20 and 22 having different characteristics, for example, a motor (not shown) Will be supplied with power.

The first and second fuel cell stacks 1
The inside of 2 and 14 is effectively cooled by the cooling medium. That is, the cooling medium supplied to the cooling medium supply port 216 is
From the cooling medium supply pipe 214 to the second end plates 24, 2
6 is supplied to a supply line 134 provided in the apparatus. As shown in FIG. 11, the cooling medium is introduced into the cooling medium supply ports 128 of the second end plates 24 and 26, and passes through the first grooves 126a from the plurality of second grooves 126b to the first cooling medium flow grooves. 124a to 124d.

The cooling medium introduced into the first cooling medium passage grooves 124a to 124d is introduced into cooling medium inlets 70a to 70d formed on the lower side of the second separator 36, and as shown in FIG. The cooling medium passages 74a to 74d communicating with the cooling medium inlets 70a to 70d move upward from below. The cooling medium that has cooled the unit fuel cells 32 through the cooling medium flow paths 74a to 74d passes through the cooling medium outlets 70e to 70h, and then passes through the second end plate 2.
4, 26 are introduced into the second cooling medium passage grooves 124e to 124h (see FIG. 11). This second cooling medium flow channel 12
4e-124h, the cooling medium introduced into the first groove 13
0a through the second groove 130b to the cooling medium outlet 13
2 to the cooling medium discharge pipe 218 from the discharge pipe 136.
Through the cooling medium outlet 220.

In this case, in this embodiment, as shown in FIG. 13, an oxidizing gas supply / discharge path 138a, a fuel gas supply / discharge path 138b, and a cooling medium supply / discharge path 138c are provided in the first fuel cell stack 12. On the other hand, in the second fuel cell stack 14, an oxidizing gas supply / discharge path 138a, a fuel gas supply / discharge path 138b, and a cooling medium supply / discharge path 138c are provided symmetrically with the first fuel cell stack 12. The second end plates 24 and 26, which are the same vertical surfaces of the first and second fuel cell stacks 12 and 14, are located at upper and lower ends on both sides in the lateral direction (the direction of arrow C) and have the oxidant gas inlet 1
20a, fuel gas inlet 122a, oxidant gas outlet 120
b and the fuel gas outlet 122b are provided symmetrically with each other.

For this reason, as shown in FIGS. 1 and 16, fuel gas supply pipes 192a, 192a, 1b communicate with respective fuel gas inlets 122a of the second end plates 24, 26.
The oxidizing gas discharge pipes 198a and 198b connecting the oxidizing gas outlets 120b with the oxidizing gas outlets 120b can be configured as short as possible, and the entire piping mechanism 28 can be effectively simplified. Is obtained. Moreover,
The second end plates 24 and 26 are provided with a supply pipe 134 and a discharge pipe 136, and the piping work of the oxidizing gas, the fuel gas, and the cooling medium is concentrated on one surface, and the workability of the piping is improved. There is an advantage that it is effectively improved.

Further, in the present embodiment, an oxidizing gas inlet 120a, a fuel gas inlet 122a, an oxidizing gas outlet 120b, and a fuel gas outlet 122b are provided at the upper and lower ends in the lateral direction in the plane of the second end plates 24 and 26. In addition, a cooling medium supply port 128 and a cooling medium discharge port 132 are provided inward in the vertical and horizontal directions (see FIG. 13). Thereby, the dimension in the height direction (the direction of arrow B) of the second end plates 24 and 26 can be made as short as possible, and the height of the fuel cell system 10 can be set low.

At this time, the first and second fuel cell stacks 12 and 14 are provided with first and second power extraction terminals 20 and 22 on the vertical surfaces on the first end plate 16 and 18 sides, respectively. There is no projecting portion such as a connection terminal on the upper side of 10. Therefore, the fuel cell system 10 is made as thin as possible, and the upper part thereof is configured to be flat, so that the space on the upper side can be effectively used, and particularly, the fuel cell system 10 can be effectively used for a vehicle. Becomes possible.

Further, in this embodiment, after assembling the first and second fuel cell stacks 12, 14, the second
The piping work of the piping mechanism 28 is performed from the end plates 24 and 26 side. Therefore, the assembling workability of the entire fuel cell system 10 is improved at once, and the fuel cell system 10 can be assembled efficiently and in a short time.

[0058]

In the fuel cell system according to the present invention, the supply and discharge paths for the fuel gas and the like are provided symmetrically in the first and second fuel cell stacks, and the adjacent vertical faces are provided with both lateral ends. Supply / discharge ports for fuel gas and oxidant gas are provided vertically and symmetrically, and supply / discharge ports for cooling medium are provided inwardly and vertically inward and leftward. Therefore, the height direction of the fuel cell stack can be effectively shortened, and the space on the upper side of the fuel cell system can be effectively used. Moreover, since the supply and discharge ports for the fuel gas, the oxidizing gas and the cooling medium are provided symmetrically on the same vertical plane of the first and second fuel cell stacks, the piping work is simplified and the manifold structure is simplified. Easy to achieve.

[Brief description of the drawings]

FIG. 1 is a schematic perspective explanatory view of a fuel cell system according to an embodiment of the present invention.

FIG. 2 is an explanatory side view of the fuel cell system.

FIG. 3 is an exploded perspective view of a main part of a fuel cell stack constituting the fuel cell system.

FIG. 4 is an explanatory longitudinal sectional view of a main part of the fuel cell stack.

FIG. 5 is an explanatory front view of one surface of a second separator constituting the fuel cell stack.

FIG. 6 is an explanatory front view of the other surface of the second separator.

FIG. 7 is a schematic vertical sectional explanatory view of the fuel cell stack.

FIG. 8 is an explanatory diagram showing a connection structure of a power extraction terminal constituting the fuel cell stack.

FIG. 9 is an explanatory perspective view of a conductive plate constituting the fuel cell stack.

FIG. 10 is an explanatory view of a flow path showing a flow of a fluid in the fuel cell stack.

FIG. 11 is an explanatory front view of an inner surface of a second end plate constituting the fuel cell stack.

FIG. 12 is an explanatory plan view of the fuel cell stack.

FIG. 13 is an explanatory front view of the fuel cell system in a state where a piping mechanism is omitted.

FIG. 14 is an explanatory rear view of the fuel cell system.

FIG. 15 is a perspective explanatory view showing a lower side of the fuel cell system.

FIG. 16 is an explanatory front view of the fuel cell system.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Fuel cell system 12, 14 ... Fuel cell stack 16, 18, 24, 26 ... End plate 20, 22 ... Power extraction terminal 28 ... Piping mechanism 30 ... Mounting mechanism 32 ... Unit fuel cell 34, 36 ... Separator 38 ... Electrolyte membrane 40 ... Cathode side electrode 42 ... Anode side electrode 56a, 66a, 100a, 120a ... Oxidizing gas inlet 56b, 66b, 100b, 120b ... Oxidizing gas outlet 58a, 68a, 102a, 122a ... Fuel gas inlet 58b, 68b , 102b, 122b ... fuel gas outlets 60a to 60d, 70a to 70d, 104a to 104d
... Cooling medium inlet 60e-60h, 70e-70h, 104e-104h
... Cooling medium outlets 72,65 ... Oxidizing gas flow grooves 72,73 ... Fuel gas flow grooves 74a-74d ... Cooling medium flow paths 80 ... Terminal plates 82,180 ... Conducting plates 106,182 ... Connecting plate portions 124a- 124h cooling medium passage groove 128 cooling medium supply port 132 cooling medium discharge port 134 supply line 136 discharge line 138a oxidizing gas supply / discharge path 138b fuel gas supply / discharge path 138c cooling medium supply / discharge Path 140 ... Tightening mechanism 142 ... Liquid chamber 146a-146c
... Disc springs 160a, 160b ... Bracket parts 162a, 162b ... Mount bracket 168 ... Rubber mounts 186a, 186b
... Stranded wires 188a, 188b ... Rubber cover

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Takeshi Ushio 1-4-1 Chuo, Wako-shi, Saitama F-term in Honda R & D Co., Ltd. (Reference) 5H026 AA06 CV06 CV08 CX06 CX09 EE18 HH03

Claims (1)

[Claims] 1. A fuel cell comprising a fuel cell stack in which a plurality of unit fuel cells each comprising a solid polymer electrolyte membrane sandwiched between an anode-side electrode and a cathode-side electrode are horizontally stacked via a separator. A system comprising: first and second fuel cell stacks arranged in parallel with each other along a stacking direction; and one end provided on a vertical surface adjacent to one end of the first and second fuel cell stacks, one of which is a positive electrode. A first and a second power extraction terminal, the other of which is a negative electrode; a fuel gas supply / discharge path, an oxidizing gas supply / discharge path, and a cooling medium supply / discharge path provided symmetrically in the first and second fuel cell stacks, respectively. A fuel gas supply port, a fuel gas exhaust port located symmetrically at each end of the first and second fuel cell stacks and located at upper and lower ends in the lateral direction. An outlet, an oxidizing gas supply port and an oxidizing gas discharge port, and the upper and lower surfaces of the fuel gas supply port, the fuel gas discharge port, the oxidizing gas supply port and the oxidizing gas discharge port, A fuel cell system comprising: a cooling medium supply port and a cooling medium discharge port that are provided inward in the left and right directions.