JPH0354434B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel cell, and more particularly to a fuel cell that can simplify the cooling structure of the cell main body.

In a conventional fuel cell, between an air electrode having an air flow path and a fuel electrode having a fuel gas flow path,
A plurality of unit cells each containing an electrolyte are arranged with separators in between to prevent air and fuel gas from mixing.

As a means of supplying air and fuel gas to the stacked batteries, manifolds are fixed to the four sides of the stacked batteries, and one side of the opposing manifolds serves as an inlet and the other serves as an outlet. Air or fuel gas is supplied all at once.

Additionally, fuel cells generally need to maintain a certain constant temperature. Therefore, in order to cool down the excess heat generated when power is generated, a cooling pipe is disposed inside the battery, passing through the manifold.

The structure of a conventional fuel cell and its drawbacks will be explained below with reference to FIGS. 1 to 3.

FIG. 1 is an exploded view of the battery components, and both the fuel electrode 1 and the air electrode 2 are provided with a large number of ribs for forming flow paths 3. As shown in FIG. Further, both electrodes have a catalyst layer 4 on their flat surfaces, and an electrolyte holding matrix 5 is attached between the electrodes so as to be in close contact with each other. The two poles are arranged so that their flat surfaces face each other, and the flow paths 3 are arranged orthogonally to each other, thereby forming a pair of unit cells. 6 is a separator arranged for each unit cell, and 7 is a cooler having a groove in which a cooling pipe 8 can be buried. One cooler is arranged in each of the plurality of unit cells. Further, the cooling pipe 8 is connected to an inlet branch pipe 9 and an outlet merging pipe 10. Further, the inlet branch pipe 9 and the outlet merging pipe 10 are connected to the inlet main pipe 11 and the outlet main pipe 12, through which cooling water as a cooling medium flows.

FIG. 2 shows the stacked state of the fuel cells, and FIG. 3 shows the state (partially broken plane) of the stacked batteries arranged in the storage tank. In these drawings, reference numeral 13 denotes a manifold that forms a space for gas supply and discharge, and is installed on four sides of the stacked battery 14. Each manifold 13 is provided with gas supply and discharge pipes 15 and 16 passing through the storage tank 17, making it possible to supply and discharge gas from outside the storage tank. In addition, since the main inlet pipe 11 and the main outlet pipe 12 for cooling are arranged in the manifold 13, the cooling water supply and discharge pipes 18 and 19 are piped to penetrate the manifold 13 and the storage tank 17. .

With this structure, air as an oxidizing agent flows as shown by the broken line arrow, and hydrogen as a fuel flows as shown as a solid line arrow, and power is generated by an electrochemical reaction in the catalyst portion.

In this manifold-type fuel cell, the cooling-related piping is arranged inside the manifold 13, making the structure extremely complex, making maintenance and inspection difficult, such as concerns about water leakage inside the manifold 13. There are drawbacks such as: Furthermore, the interior of the manifold 13 is filled with vapor of phosphoric acid, which is an electrolytic solution, and there is a possibility of contact with this phosphoric acid vapor, which has disadvantages such as limitations on the materials that can be used.

An object of the present invention is to provide a fuel cell with a simple structure and high reliability by improving the configuration for supplying and discharging a cooling medium to a cooler arranged for each of a plurality of single cells.

That is, the present invention introduces an inlet branch pipe and an outlet merging pipe that connect the main inlet and outlet pipes and the cooler, respectively, from between adjacent manifolds, and connects the led-out inlet branch pipe and outlet merging pipe with the inlet and outlet. The inlet and outlet main pipes are connected to each other by flexible joints made of insulating material, and the inlet and outlet main pipes are slidably supported by the battery clamping plate, and the inlet and outlet main pipes are connected to water supply and discharge pipes via flanges. They are designed to be combined with each other to achieve the desired purpose.

An embodiment of the present invention will be described below with reference to FIGS. 4 and 5.

Figure 4 shows an example in which the battery of the present invention is housed in a storage tank. Figure 4 shows the state in which the pipe leading to the cooler is arranged between the manifolds, and Figure 4 shows the state as seen from the air inlet side. It is shown in Figure 5. As shown in these drawings, the pipes to the cooler are provided with an inlet branch pipe 9 and an outlet merging pipe 10 between manifolds 13 adjacent to each other; A plurality of cooling pipes 8 are fixedly arranged, and the inlet branch pipe 9 and the outlet merging pipe 10 are connected to the inlet main pipe 11 and the outlet main pipe 12 via joints 75, respectively. The main inlet pipe 11 and the main outlet pipe 12 are supported by a receiver 74 fixed to a battery clamping plate 71 with bolts 76, as shown in FIG.

In such a configuration, cooling water as a cooling medium is guided to the main inlet pipe 11 by the water supply pipe 18 fixed to the battery holder 77 and introduced into the cooling pipe 8 from the inlet branch pipe 9. Here, a plurality of cooling pipes 8 are arranged so that cooling water is uniformly distributed within the battery. Next, the water after cooling goes through the reverse route of water supply.
That is, it is discharged to the outside in the order of the outlet merging pipe 10, the outlet main pipe 12, and the discharge pipe 19. In other words, the cooling water flows as indicated by the dotted line arrow.

The piping of the cooling system is the inlet and outlet main pipes 11 and 12.
The water supply and discharge pipes 18, 19 are connected by flanges 78, and the inlet branch pipes, outlet merging pipes 9, 10, and inlet and outlet main pipes 11, 12 are connected to joints 7 made of insulating material.
5 and are connected outside the manifold 13, making assembly and disassembly work very easy, and inspection etc. easy.

Generally, in a fuel cell, the temperature inside the battery storage tank is maintained at a high temperature (approximately 190°C) during power generation, and returns to room temperature when stopped. Therefore, expansion and contraction occur in the inlet and outlet main pipes 11, 12, inlet branch pipes, outlet merging pipes 9, 10, etc. due to temperature changes of the cooling water. In order to alleviate and absorb their expansion and contraction, the receiver 74 has a slidable structure, and the joint 75 has a flexible pipe structure. In particular, since the joint 75 is made of an insulating material, electrical short circuit with the cooling pipe 8 can be prevented, which is effective.

As described above, if the fuel cell is configured as in the present invention, the inlet branch pipe and outlet merging pipe connecting the cooler and the inlet and outlet main pipes, and the inlet and outlet main pipes are not disposed inside the manifold, and The inlet and outlet main pipes are slidably supported by the battery clamping plate, and are connected to the inlet branch pipe and the outlet merging pipe by flexible joints made of insulating material.
Water leaks in each piping to the cooler and abnormalities in the joints can be easily monitored, and expansion and contraction of the main inlet and outlet pipes is alleviated, reducing excessive force on joints such as inlet branch pipes and outlet merging pipes. It becomes more robust without adding any additional weight, improves reliability, and furthermore, makes disassembly, assembly, inspection, and other operations extremely easy.

[Brief explanation of drawings]

Figure 1 is an exploded view showing a conventional fuel cell configuration, Figure 2 is a schematic perspective view showing the stacked state of Figure 1, and Figure 3 is a schematic perspective view showing the stacked state of Figure 1.
FIG. 4 is a plan view showing a fuel cell stored in a stacked battery storage tank; FIG. 4 is a plan view showing a fuel cell according to an embodiment of the present invention stored in a storage tank;
FIG. 5 is a side view of FIG. 4 viewed from the air inlet side. 1... Fuel electrode, 2... Air electrode, 7... Cooler,
9...Inlet branch pipe, 10...Outlet merging pipe, 11...
...Inlet main pipe, 12...Outlet main pipe, 13...Manifold.

Claims (1)

[Claims] 1. A plurality of single cells each containing an electrolyte between an air electrode and a fuel electrode having gas flow passages are stacked,
A battery clamping plate is tightened to form a stacked battery, and a manifold for supplying air and fuel gas is fixed to the four sides of the stacked battery, and an inlet branch pipe is connected to the inlet and outlet main pipes for each of the plurality of single cells. and a cooler in which a cooling medium flows through an outlet merging pipe, in which an inlet branch pipe and an outlet merging pipe connecting the inlet and outlet main pipes and the cooler are led out from between adjacent manifolds, and The led-out inlet branch pipe and outlet merging pipe are coupled to the inlet and outlet main pipes using flexible joints made of an insulating material, and the inlet and outlet main pipes are slidably supported by a battery clamping plate, and A fuel cell characterized in that the inlet and outlet main pipes are connected to water supply and discharge pipes, respectively, via flanges.