JPS6124169A - Fused carbonate type fuel cell - Google Patents

Abstract

PURPOSE:To obtain a fuel cell excellent in a gas-sealing property, prevent the wetting of a reforming catalyst due to an electrolyte, and efficiently perform the internal reforming reaction by providing a reaction gas feed hole and a reaction pipe arranged in it and filled with a reforming catalyst inside a laminated body. CONSTITUTION:The anode gas such as natural gas or coas gas is first fed to a reaction pipe 11. The anode gas reformed by the action of a reforming catalyst 9 while passing the reaction pipe 11 turns at the top of the reaction pipe 11 and flows downward around the reaction pipe 11, i.e., inside a reaction gas feed hole 10, and is fed to individual anodes 5 through anode gas passages 6 communicated to the reaction gas feed hole 10. A reaction gas feed hole having no reaction pipe 11 is provided on cathodes 3 in parallel with the lamination direction like the case of the anodes 5, and the cathode gas is fed to individual cathode gas passages 2 through this reaction gas feed hole, thereby the cathode reaction is generated, and the cell reaction proceeds as a whole together with the anode reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION TECHNICAL FIELD OF THE INVENTION This invention relates to molten carbonate fuel cells, and in particular to reactant gas supply mechanisms.

[Conventional technology]

FIG. 1 shows a conventional molten carbonate fuel cell. In the figure, (υ is the end plate, 12) is the cathode current collector plate and gas flow path, that is, the gas separation plate of the flow path bone, (3) is the cathode, (4) is the electrolyte holder, (5j is the anode/( 61 is a current collector plate for the anode and a gas flow path, that is, a nocas separation plate with a flow path, (7) is a manifold, and (8) is a gasket for manifold sealing.Anode electrode (5) facing
A single cell is constituted by the electrolyte holder (4) interposed between the cathode electrode (31 and both electrodes <s+, (51), and the cell and the gas separation plate (21, +61) are alternately laminated to form a laminate. Figure 2 shows the manifold arrangement and gas flow of the fuel cell shown in Figure 1.

FIG. 8 shows a modification of FIG. 1 in which the anode (6) is provided with irregularities and the recesses are filled with a reforming catalyst (9).

Next, the operation will be explained. In the case of the fuel cell shown in Fig. 1, the anode gas introduced from the manifold (7) flows in the direction of the arrow and reaches the anode.

Causes an anode reaction. - 10,000, cathode gas was introduced into the cathode (3) from a similar manifold in a direction perpendicular to the plane of the paper of FIG. 1, and a cathode reaction occurred.

Together with the above anode reaction, a battery reaction is established.

Electricity is generated as a fuel cell. The manifold (7) is pressed against the side surface of the laminate through the gasket (8) to ensure gas sealing. In the case of the fuel cell shown in FIG. 8, methane (C
Natural gas or coal gas whose main component is H4) is reformed and converted into a gas whose main component is hydrogen, which is immediately used in the anode reaction, and an efficient fuel cell was expected.

Since the conventional molten carbonate fuel cell is constructed as described above, first, when the gasket (8) is used to seal the manifold (7), the electrolyte and the temperature are controlled.

Furthermore, in the case of an internal reforming catalyst (9), the electrolyte holder (4)
This had the disadvantage that the electrolyte from the reforming catalyst (9) permeated and wetted the reforming catalyst (9), resulting in a decrease in catalytic activity.

(Summary of the Invention) This invention was made to eliminate the drawbacks of the conventional ones as described above, and includes a reaction gas supply hole provided inside the stack in parallel with the stacking direction and communicating with the anode gas flow path.
and a reaction tube disposed inside the reaction gas supply hole and filled with a reforming catalyst, and by guiding the gas reformed by the reforming catalyst to the reaction gas supply hole, the gas sealing property is improved. It is an object of the present invention to provide a molten carbonate fuel cell which has excellent properties and is capable of efficiently carrying out an internal reforming reaction by preventing wetting of the reforming catalyst by the electrolyte.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings. Fourth
The figure is a sectional view showing a molten carbonate fuel cell according to an embodiment of the present invention. In fig.

Q (I is a reaction gas supply hole, which is provided inside the stack in parallel with the stacking direction and communicates with the anode gas flow path (6). The east side is a reaction tube, and in this example, a part of the reaction gas supply hole The pores are disposed inside and filled with a reforming catalyst (9).

Note that arrows indicate the flow of anode gas.

Next, the operation will be explained. An anode gas such as natural gas or coal gas is first supplied to the reaction tube (b). The anode gas reformed by the action of the reforming catalyst (9) while passing through the reaction tube αυ turns from the top of one reaction tube turn to the outer periphery of the reaction tube (b), that is, the inside of the reaction gas supply hole OQ. 1ζ is supplied to each anode 15) from an anode gas flow path (6) that flows downward and communicates with the two reaction gas supply holes QO.

Thereafter, most of the gas contributes to the reaction, while some remains unreacted, reaches the reaction gas supply hole QG on the left side of FIG. 4, and is discharged to the outside. In other words, natural gas and coal gas, which are the 7-node gases for the molten carbonate fuel cell, are led to the reaction tube αη, and the stack is operated at 650°C, so the reforming reaction is carried out by boiling the reaction tube at the same temperature. The generated and reformed gas is transferred to the reaction tube aυ
Since the reactant gas supply hole Q (I is in communication with the anode gas flow path (6)), the reformed gas quickly permeates into the anode (5). Contributes to the anode reaction. - In the cathode (3), reactant gas supply holes (not shown) without reaction tubes (b) are stacked on the front and opposite sides of the drawing in the same way as the anode (6). A cathode reaction occurs by supplying cathode gas to each cathode gas flow path (second ζ) through this reaction gas supply hole, and the battery reaction as a whole proceeds together with the above-mentioned anode reaction.

With such a reaction gas supply mechanism, the manifold for supplying the reaction gas, that is, the reaction gas supply hole QO, can be easily sealed, and the reforming reaction of the anode gas can be carried out inside the reaction gas supply hole QQ. Since the reforming catalyst (9) can be prevented from being wetted by the electrolyte, a highly reliable and highly efficient cell reaction can be obtained.

Although the above embodiment shows the case where the anode gas is introduced into the reaction tube (b) from below the stacked body, it may also be introduced from above.

In addition, in the above embodiment, the anode (
Although we have explained the case in which a reaction gas supply hole QO similar to that on the 5) side is provided, even if a box-shaped so-called external manifold (7) as shown in the conventional example in Fig. 1 is provided on the cathode (IJ side), Effects similar to those of the embodiment can be obtained.

[Effects of the Invention] As described above, according to the present invention, there is a reaction gas supply hole provided inside the laminate in parallel with the stacking direction and communicating with the anode gas flow path, and a reaction gas supply hole provided inside the reaction gas supply hole. The structure is equipped with a reaction tube filled with a reforming catalyst, and the gas reformed by the reforming catalyst is guided to the reaction gas supply hole, so that it has excellent gas sealing properties, and the electrolyte of the reforming catalyst It has the effect of preventing wetting and allowing internal reforming reactions to occur efficiently.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing an example of a conventional molten carbonate fuel cell, Figure 2 is an explanatory diagram schematically showing the arrangement of the manifold and the flow of reactant gas in the fuel cell shown in Figure 1, and Figure 8. FIG. 4 is a sectional view showing a main part of a modification of the conventional molten carbonate fuel cell shown in FIG. 1, and FIG. 4 is a sectional view showing a molten carbonate fuel cell according to an embodiment of the present invention. In the figure, (21, (61 is the gas separation plate of the gas flow path bone, (3) is the cathode, (4) is the electrolyte holder, (5)
is an anode, (9) is a reforming catalyst, Q (I is a reaction gas supply hole, and C1υ is a reaction tube. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] Single cells having an anode and a cathode facing each other with an electrolyte holder interposed therebetween, and gas separation plates that separate an anode gas flow path facing the anode from a cathode gas flow path facing the cathode are alternately laminated. In the molten carbonate fuel cell which constitutes a stacked body, a reactive gas supply hole is provided in the stacked body in parallel with the stacking direction and communicates with the anode gas flow path, and a reactive gas supply hole is arranged inside the reactive gas supply hole. 1. A molten carbonate fuel cell comprising a reaction tube filled with a reforming catalyst, the gas being improved by the reforming catalyst being guided to the reaction gas supply hole.