JPH0367306B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel cell with a matrix.

As is well known, a phosphoric acid aqueous solution fuel cell consists of a matrix impregnated with an electrolytic solution, gas diffusion electrodes stacked on both sides, and gas separation plates with gas supply grooves stacked on the outer surface of each electrode. A single cell is constructed, and multiple cells are stacked to form a battery stack, and fuel gas (hydrogen) and air (oxygen) are supplied in cross directions, and the electrical energy generated from each single cell is combined. The energy of a predetermined voltage and current is obtained.

By the way, as a conventional means for supplying and discharging reactive gases of hydrogen and oxygen, as shown in FIG.
Although the battery stack 1 is attached using the pressing force of a spring, the material of which the battery stack 1 is made has low mechanical strength, so the manifold 2 cannot be firmly pressed against the upright surface of the battery stack, and the battery stack 1 are tightened by applying pressure from above and below, and adjusting the tightening pressure may create a gap between the manifold and the battery stack, or the manifold may become distorted due to the heat generated in the battery stack, causing gas leakage. There was a flaw that caused it.

The object of the present invention is to solve the above-mentioned conventional drawbacks, and in particular to provide a fuel cell that can protect the mechanically weak upright surfaces of the cell stack and increase the gas supply pressure. It is in.

The structure according to the present invention provides a fuel cell in which a battery stack in which a plurality of unit cells having a square plane are stacked is stored in a pressed state in a casing made of a circular cylinder. A convex portion serving as a seal is formed by interposing a sealing material between the upper and lower protrusions protruding from the gas separation plate that covers both the front and back surfaces of each unit cell, and a concave portion is provided on the inner peripheral surface of the casing. The protrusion is engaged with the protrusion through a sealing material.

The present invention will be explained below with reference to Examples.

As shown in Figures 2 and 3, a cylindrical part 3 made of electrically insulating material and having a circular cross section (ideally a perfect circle)
A hollow casing 6 is formed by closely contacting the upper and lower open openings with cover plates 4 and 5, respectively, and the battery stack 1 having a square plane is placed inside the casing 6 by the lower cover plate 5.
The battery stack 1 is fastened with an inflatable body 7 made of air or water interposed between the upper surface of the battery stack 1 and the upper cover plate 4. In addition, each corner of the housed battery stack 1 is brought into contact with the inner circumferential surface of the casing 6 via the seal portion 16, and each of the surrounding upright surfaces of the battery stack 1 and the casing 6 are brought into contact with each other.
Space portions 8, 9, 10, and 11 are formed between the inner circumferential surfaces of. Note that, in accordance with the principle of fuel cells, the supply ports 12 and 13 and the discharge ports 14 and 15 are provided facing each other.

Therefore, the structure of the seal portion 16 is shown in FIGS. 4 to 6, but prior to that description, the structure of the battery stack 1 will be explained.

The battery stack 1 is made up of a plurality of single cells 17 stacked together as described above.The single cells 17 are made by joining gas diffusion electrodes 19 and 20 having catalyst layers on both sides of a matrix 18 impregnated with an electrolytic solution. Gas separation plates 21 and 22 are superimposed on the outer surfaces of 19 and 20,
Gas supply grooves 23, 23 are provided perpendicularly on both the front and back surfaces of each gas separation plate 21, 22.

In the cell 17 described above, a projecting piece 24 is integrally provided at each corner of both the upper and lower gas separation plates 21 and 22. A sealing material 25 such as silicone rubber or foam is interposed between the protrusions 24, 24 facing each other at the top and bottom of the unit cell 17 thus formed. When the battery stack 1 is formed by stacking the unit cells 17 thus formed, a convex portion 26 is formed at each corner to prevent gas leakage between the stacks, as shown in FIG. When storing this battery stack 1 in the casing 6, a recess 27 is provided on the inner circumferential surface of the casing 6 over the entire length in the height direction, and the protrusion 26 is engaged with the recess 27. A sealing material 28 formed of a tube is interposed between the distal end surface of the portion 26 and the inner surface of the recessed portion 27 over the entire length in the height direction, thereby isolating the adjacent spaces 8 to 11 from each other.

According to the fuel cell having the above structure, by injecting fluid into the expansion body 7 and causing it to expand, the battery stack 1 is fixed in a tightened state within the casing 6, and the sealing material 28 made of a tube is also A fluid is introduced, and its expansion force brings the battery stack 1 into close contact with the inner circumferential surface of the casing 6. Hydrogen is supplied to one space 8, oxygen is supplied to one space 9 adjacent to this, and these relative Electric power is generated by discharging air from the space portions 10 and 11 facing each other.

The effect of this invention is that a square battery stack is housed in a circular cylindrical casing, and a space is provided between each side of the battery stack and the inner peripheral surface of the casing.
In order to partition each space, seals provided at each corner of the battery stack are engaged in recesses provided on the inner peripheral surface of the casing. Since the sealing material is interposed between the protruding pieces protruding from the gas separation plate, even if this sealing part comes into strong pressure contact with the casing, it will not have any effect on the battery stack, which is weak in mechanical strength. This provides a reliable sealing effect and improves its durability.

[Brief explanation of drawings]

Figure 1 is a perspective view showing the main parts of a conventional fuel cell;
FIG. 2 is a cross-sectional view showing the main parts of the fuel cell according to the present invention, FIG. 3 is a vertical cross-sectional view, FIG. 4 is a perspective view showing the seal structure of the unit cell, and FIG. 5 is shown in FIG. FIG. 6 is a perspective view showing a battery stack having a sealing function by stacking unit cells, and FIG. 6 is a partially enlarged cross-sectional view showing the sealed state of the casing and the battery stack. 1...Battery laminate, 6...Casing, 7...
Expandable body, 8, 9, 10, 11... Space part, 12,
13...Inlet, 14,15...Outlet, 16...
... Seal part, 17 ... Cell, 18 ... Matrix, 19, 20 ... Gas diffusion electrode, 21, 22 ...
... Gas separation plate, 24 ... Projection piece, 25 ... Sealing material,
26...Convex portion, 27...Concave portion, 28...Sealing material.

Claims (1)

[Claims] 1. In a fuel cell in which a battery stack in which a plurality of unit cells with a square plane are stacked is housed in a pressed state in a casing made of a circular cylinder, each corner of the battery stack serves as a sealing part. The convex portion is formed by interposing a sealing material between the upper and lower protruding pieces protruding from the gas separation plates covering both the front and back surfaces of each unit cell, and the convex portion is inserted into the concave portion provided on the inner peripheral surface of the casing. A fuel cell characterized in that the fuel cells are engaged through a sealing material.