JPS6353862A - Gas supply and exhaust device for fuel cell - Google Patents

Abstract

PURPOSE:To make it possible to distribute the gas among each block, by arranging the branch pipes each after branching and before joining in a way as to be vertically symmetrical. CONSTITUTION:Piping is constituted in such a way as branching a gas stream from a main supply pipe 5 twice then leading the gas to flow manifolds 7 to 10 on the inlet side, and joining the gas streams from manifolds 11 to 14 on an outlet side twice then leading the gas to flow in the main exhaust pipe 6. And also, as the branching pipes 15 to 26 for each branching or branched streams to be formed vertically symmetrical. By this, the gas is equally distributed and passes through the laminated cells 1 to 4 respectively. Thus, distribution of the gas among each block can be made uniform.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a gas supply/discharge device for a fuel cell.

[Conventional technology]

Gas supply and exhaust to the stacked cells of a fuel cell is described, for example, in Japanese Patent Application Laid-open No. 6
As described in Publication No. 0-205975, a battery body consisting of six stacked cells and a manifold is stacked in multiple stages, which is connected from the outside by gas piping via a manifold that distributes oil around the stacked cells. Almost no technology regarding the gas piping structure in such cases has been disclosed.

[Problems to be Solved by the Invention] In general, as the capacity of the stack increases, the number of stacked cells increases, and the surface pressure of the lower cells will exceed the allowable limit due to their own weight. For this reason, when the laminated cell is divided into multiple blocks and each is individually tightened, and the surface pressure is kept within the allowable limit by adjusting the tightening force, the manifold is also divided into multiple blocks. can be installed.

In this case, if the gas distribution to each block is uneven, the performance of the battery may be significantly impaired.

The present invention has been made in view of the above points, and it is an object of the present invention to provide a gas supply/discharge device for a fuel cell that makes it possible to evenly distribute gas between each block.

[Means for solving problems]

The above purpose is to increase the number of stacked cells to the Nth power of 2 (N is an integer that is not 0)
N is divided equally into
It is connected to the manifold of each block through N times of branching, and is connected to the discharge main pipe to the outside through N times of merging from the manifold of each block. This can be achieved by designing the piping so that it is symmetrical.

[Effect]

The gas supplied from the outside in each gas system enters the inlet manifold of each block through N branches from the supply main pipe, and reacts in the stacked cells.

After passing through N times of merging from the manifold on the outlet side of each block, it flows to the outside from the discharge main pipe. Since the branch pipes after each branch and before merging are vertically symmetrical, and the stacked cells are equally divided, gas flows at the same flow rate in each block. Further, since the number of blocks is 2 to the N power, where N is a positive integer that is not 0, such a top-bottom symmetric piping structure is not obstructed.

〔Example〕

The present invention will be explained below based on the illustrated embodiments. FIG. 1 shows an embodiment of the invention. As shown in the figure, a supply/discharge main pipe 5,
6. Gas is supplied through the inlet/outlet side manifolds 7 to 14 provided in the laminated cells 1 to 4 and the branch pipes 15 to 26 connecting these supply/discharge main pipes 5, 6 and the inlet/outlet side manifolds 7 to 14. is supplied and discharged. In the same figure, 27
is a pressure vessel. In this embodiment, in the fuel cell gas supply/discharge device configured as described above, the branch pipes 15 to 26 are connected to the inlet side after passing through the supply main pipe 5 N times (N=2 in this case), that is, two gas branches. Connect manifolds 7 to 10,
The outlet manifolds 11 to 14 are configured to be connected to the exhaust main pipe 6 through gas merging twice, and the branch pipes 15, 16, 17, and 18 for each of the two merging branches.
・20.21・2.2, 23・24, 25・26 above,
Formed downwardly symmetrically. By doing this, branch pipe 1
5 to 26 are connected to the inlet side manifolds 7 to 10 through two gas branches from the supply main pipe 5, and are connected to the discharge pipe 6 through two gas confluences from the outlet side manifolds 11 to 14.
The branch pipes 15, 16, 17, 18, 19, 20° 21
・22.23, 24, 25, and 26 are now formed symmetrically below, so that the gas is equally distributed and passes through the laminated cells 1 to 4, respectively, and the gas distribution between each block is improved. It is possible to obtain a gas supply and discharge device for a fuel cell that makes it possible to equalize the amount of gas.

That is, the main pipe 5 for supplying gas from the outside is connected to the first branch point 2.
The branch pipes 15.16 are branched at a second branch point 29.30 and connected to the branch pipes 17, 18 and 19.20, respectively. are connected to the inlet side manifolds 7 to 10, respectively.

Of these branch pipes 15 to 20, branch pipes 15 and 16, 17 and 18, and 19 and 20 are attached symmetrically upward and downward, respectively. Similarly, for the piping on the gas exhaust side, the exhaust main pipe 6 to the outside is branched off at the first branch point 31 and connected to the branch pipe 25.2B, and these branch pipes 25.26 are connected to the second branch point, respectively. Branched at 32 and 33, each branch pipe 2
1.22 and 23.24, which are connected to outlet manifolds 11 to 14, respectively.

Of these branch pipes 21 to 26, branch pipes 25 and 26, 21 and 22, and 23 and 24 are installed symmetrically above and below.

With such a configuration, gas supplied from the outside is supplied to the supply main pipe 5.
These gases are then branched into branch pipes 15 and 16, and further branched into branch pipes 17 and 18 and 19 and 20, respectively.
10.

The gas flowing into the inlet manifolds 7 to 10 passes through the laminated cells 1 to 4, respectively, and then flows from the outlet manifolds 11 to 14 to the discharge side branch pipes 21 to 2, respectively.
4, the gases in the branch pipes 21.22 and 23.24 join together and flow into the branch pipes 25.26, respectively, and further join together and are discharged to the outside after passing through the discharge main pipe 6. Stacked cells 1 to 4 and inlet manifolds 7 to 1
The 0° outlet side manifolds 11 to 14 have the same shape, and the supply side branch pipes 15, 16, 17, 18.
19 and 20 and the discharge side branch Ir! 25 and 26.21
and 22, 23 and 24 are symmetrical to each other, so that the gas passes through the stacked cells 1 to 4 with equal distribution. In this way, according to this embodiment, the divided stacked cells 1 to 4
Since gas can be equally distributed to each block of the fuel cell, there is no fear that the performance of the cell will be affected, and the reliability of the fuel cell can be improved.

Note that this embodiment is similar to other N that is a positive integer other than 60, which corresponds to N = 2 when the number of divisions of the stacked cell is 2 to the N power. The number of branches will be N times for each of the gas supply and discharge side pipes.

〔Effect of the invention〕

As described above, the present invention is capable of equalizing gas distribution between each block, thereby obtaining a gas supply/discharge device for a fuel cell that makes it possible to equalize gas distribution between each block. Can be done.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a fuel cell according to an embodiment of the fuel cell gas supply/discharge device of the present invention. 1-4... Laminated cell, 5... Supply main pipe, 6... Discharge main pipe, mouth side manifold, 15-26... Branch pipe.

Claims (1)

[Scope of Claims] 1. A stacked body in which a predetermined number of stacked unit cells are stacked in 2<N> stages is provided with a supply/discharge main pipe, an inlet/outlet side manifold provided in the stacked cells, and these supply/discharge main pipes. In a gas supply/discharge device for a fuel cell in which gas is supplied and discharged via a branch pipe connecting a main pipe and an inlet/outlet side manifold, the branch pipe is used to branch the gas N times from the supply main pipe. It is configured to connect to the inlet side manifold through the outlet side manifold, and connect to the discharge main pipe through the N times of gas merging from the outlet side manifold, and connect the branch pipes for each branch and merging to the upper, A gas supply and discharge device for a fuel cell characterized by being formed downwardly symmetrically. 2. The gas supply/discharge device for a fuel cell according to claim 1, wherein the N is a positive integer other than 0.