JPS60241657A - Fuel cell - Google Patents

Abstract

PURPOSE:To improve the sealing performance by mounting a gas supply/discharge manifold onto a fuel cell body through a gasket composed of a tubular tetrafluoride ethylene resin and a rubber resin inserted into it. CONSTITUTION:A plurality of unit cells having a pair of gas dispersion electrodes and electrolyte are laminated then held between sealing conductors 1 to form a fuel cell body 2. Then a gas supply/discharge mainfold 3 is fixed to the sideface of said body 2 through a gasket 4A comprised of a tubular tetra-fluoride ethylene resin 6 and a rubber resin 7 inserted into said resin 6 and sealed. It can be contacted tightly against the coarse face of the body 2 through soft resin 6 while fastening pressure can be maintained constant through resiliency of rubber resin 7 resulting in a sealing structure having high air-tightness and improvement of safety.

Description

[Detailed description of the invention] [Field of application of the invention] The present invention relates to fuel cells.

[Background of the invention]

In general, a fuel cell has a gas diffusion electrode that has a flow path for air, which is an oxidizing gas, a gas diffusion electrode that has a flow path for hydrogen, which is a fuel gas, and an electrolyte such as phosphoric acid between these pair of gas diffusion electrodes. unit battery (none shown)
As shown in Fig. 1(a) and (b), a plurality of them are stacked in a number corresponding to the battery output, and the upper and lower parts are covered with sealing conductor 1.
These constitute the scissor battery body 2. As a means for supplying and discharging oxidizing gas and fuel gas to and from the battery body 2 stacked in this manner, a manifold 3 is fixed to the side surface of the battery body 2 through a gasket 4 such as an O-ring within a groove 3 provided on this side. One side of the manifold 3 serves as an inlet and the other serves as an outlet, and oxidizing gas or fuel gas is supplied and discharged to and from each unit cell at once.

In the fuel cell configured in this way, the portion where the battery body 2 and the sealing conductor 1 come into contact with the manifold 3 is sealed with a gasket 4 made of fluororubber.
Due to dimensional errors during battery manufacturing and work errors during battery stacking, unevenness occurs on the surface where the gasket 4 contacts, as shown in FIG. i5 may occur.

This is because the gasket (4) has no elasticity, but if a gap (5) occurs, gas leaks and not only does it become impossible to control the operating pressure properly, but also there is a risk of explosion due to the mixture of hydrogen and oxygen. there were.

[Purpose of the invention]

The present invention has been made in view of the above points, and it is an object of the present invention to provide a fuel cell in which the sealing performance between the cell main body and the manifold can be completely improved.

[Summary of the invention]

That is, the present invention includes a battery body in which a plurality of unit cells each having a pair of gas diffusion electrodes and an electrolyte are stacked, and a manifold arranged on a side surface of the battery body for supplying and discharging gas to and from the battery body. In a fuel cell in which the battery body and the manifold are sealed with a gasket, the gasket is made of a tubular polytetrafluoroethylene resin;
The gasket is characterized by being formed of a rubber-like resin inserted into this resin, so that the gasket is formed of a tubular tetrafluoroethylene resin and a rubber-like resin inserted into this resin. become.

[Embodiments of the invention]

The present invention will be explained below based on the illustrated embodiments. An embodiment of the present invention is shown in FIGS. 3 and 4. Note that parts that are the same as those in the conventional system are given the same reference numerals, and therefore their explanations will be omitted. In this implementation, gas'! T) 4A was formed from a tubular tetrafluoroethylene resin 6 and a rubber-like resin 7 inserted into the resin 6. By doing this, the four gaskets are formed of the tubular polytetrafluoroethylene resin 6 and the rubber-like resin 7 inserted into this resin 6, and the battery body 2 and the manifold 3 are connected to each other. It is possible to obtain a fuel cell in which the sealing performance between the fuel cell and the fuel cell can be improved.

That is, the heat-resistant, acid-resistant and electrically insulating tubular polytetrafluoroethylene resin 6, which is flexible and has heat resistance, acid resistance, and electrical insulation properties, is placed on the uneven surface of the laminated portion of the battery body 2 where the battery body 2 and the manifold 3 face each other. A gasket (4A) formed by inserting a rubber-like resin 7 having elasticity and elasticity, such as fluorine rubber, was applied. That is, the gasket 4A'i was placed in the groove 3A provided on the side of the manifold 3 facing the battery body 2. By doing this, the tubular polytetrafluoroethylene resin of 4A has flexibility, so it can adhere sufficiently to the uneven surface of the laminated part of the battery body 2, and it has a rubber-like appearance. Since the resin 7 has elasticity, it is possible to maintain the clamping pressure of the manifold 3 constant even when the battery operating temperature changes. Therefore, it is possible to absorb dimensional errors during battery manufacturing and work errors during battery stacking, to obtain a seal structure with excellent airtightness between the battery body 2 and the manifold 3, and to facilitate operation pressure control. A safe fuel cell without the danger of explosion due to mixing can be obtained.

Although fluorine-based rubber was used as the rubber-like resin 7 in this embodiment, silicone-based rubber may also be used, and room-temperature curing or heat-curing rubber paste such as silicone rubber paste or fluorocarbon paste may also be used. It is filled between the manifold 3 and the battery body 2 in a certain state, and then hardened.

By doing so, it is possible to further improve the adhesion of the outer tubular tetra7fluoroethylene resin 6 to the uneven surface of the battery body 2. Since this rubber-like resin 7 is covered on the outside with a polytetrafluoroethylene resin 6 having excellent acid resistance, it does not require particularly severe acid resistance, and inexpensive materials can be used.

〔Effect of the invention〕

As described above, the present invention improves the sealing performance between the battery main body and the manifold, thereby making it possible to obtain a fuel cell in which the sealing performance between the battery main body and the manifold can be improved.

[Brief explanation of drawings]

Fig. 1(a) is a partial vertical side view of a conventional fuel cell;
Figure (b) is a partial side view of Figure 1 (a), and Figure ≠ 2.
The figure is an enlarged sectional view of the main parts of a conventional fuel cell, FIG. 3 is a front view showing the configuration of a gasket of an embodiment of the fuel cell of the present invention, and FIG. FIG. 3 is an enlarged sectional view of the gasket enclosure, showing a state in which it is disposed between the gasket enclosure and the gasket enclosure. 1... Sealing conductor, 2... Battery body, 3... Manifold, 3 people... Groove, 4A... Gasket, 6...
...Tubular tetrafluoroethylene resin, 7...Rubber-like resin. Agent Patent Attorney Akio Takahashi Figure 11 (α) (b) Funeral 3 Shiryu

Claims (1)

[Claims] 1. A battery body in which a plurality of unit batteries each having a pair of gas diffusion electrodes and an electrolyte are stacked, and a manifold arranged on a side surface of the battery body and supplying and discharging gas to and from the battery body. In the fuel cell, the battery main body and the manifold are sealed with a gasket, wherein the gasket is formed of a tubular tetrafluoroethylene resin and a rubber-like resin inserted into the resin. fuel cell. 2. The fuel cell according to claim 1, wherein the rubbery resin is silicone-based or fluorine-based rubber. λ The fuel cell according to claim 1, wherein the comb-shaped resin is a silicone rubber paste or a fluorine rubber paste.