JPS6361384B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention is a method of attaching porous oxide electrode films to both sides of a solid electrolyte membrane on the outer peripheral surface of a porous hollow ceramic tube (hereinafter referred to as a base tube). This invention relates to a gas masking device for thermal spraying used when manufacturing solid electrolyte fuel cells.

[Conventional technology]

FIG. 4 is a side sectional view schematically showing a solid electrolyte fuel cell (hereinafter referred to as a cell stack), in which 1 is a base tube, 1a is an electrode on the fuel gas side, 1b is a solid electrolyte membrane, 1c is an electrode on the oxygen side, 1d is a current lead.

The open circuit voltage per element of a solid electrolyte fuel cell is approximately 1V, so in order to obtain a high output voltage, it is necessary to connect a plurality of elements in series.

There were many problems to be solved in the fabrication of series connected battery stacks. In particular, it is necessary to form a film by melting solid electrolyte materials and oxides with high melting points, and plasma arc spraying is used for the former, while acetylene flame spraying is used for the latter. Ru.

In order to connect solid electrolyte fuel cell elements in series, it is necessary to adopt a pattern as shown in FIG. 4. Since both the plasma arc spraying method and the acetylene flame spraying method involve high temperatures of over 2000°C, when manufacturing a battery stack, the conventional method is to provide a slit between the base tube 1 and the plasma arc spraying gun or the acetylene flame spraying gun. It was used.

On the other hand, in the thermal spraying method, particles melted at high temperatures fly at high speed, pass through the slit, diffuse, and adhere to the outer peripheral surface of the base tube 1 with a width wider than the slit width.

[Problem that the invention seeks to solve]

FIG. 5 is a perspective view showing an outline of battery stack manufacturing using the conventional slit method. A slit plate 2 is provided between the base tube 1 and the thermal spray gun 3. Although metal is used as the material for the slit plate 2 in order to withstand thermal shock, thermal expansion occurs and the slit plate 2 becomes distorted. Furthermore, if the substrate is brought too close to the substrate gap 1 to prevent the above-mentioned diffusion, the substrate will warp due to thermal expansion, come into contact with the substrate, and be destroyed.

In addition, the cross-sectional shape of the membrane obtained by this is
It is shown in FIG. Reference numeral 4 denotes a membrane, as shown in the figure, and it is necessary to provide a sufficiently wide space between adjacent membranes 4. The high-speed fine particles sprayed by the thermal spray gun 3 diffuse and form a film 4 with unclear boundaries. For this reason, it was necessary for the axial distance between adjacent membranes 4 to be 5 mm or more. This increases the length of the part where the solid oxide fuel cell elements are connected in series (referred to as an intermediate connector), which reduces the number of battery elements to be manufactured and reduces the length of the base tube 1 used. A portion of the generated power is consumed by this intermediate connector, reducing the power generation effect. Therefore, the intermediate connector must be as short as possible. For this purpose, it is necessary to prevent the membrane 4 from spreading in the direction of the base tube 1 due to diffusion phenomena.

With the conventional slitting method, these drawbacks and inadequacies could not be overcome, and the characteristics of the manufactured battery stacks were far below the theoretical values, and the quality of each stack could not be made uniform.

This invention was made to solve the above problems, and aims to significantly improve fuel cell stack characteristics, uniformity of quality, and production efficiency.

[Means for solving problems]

The gas masking device for thermal spraying according to the present invention includes:
A semicircular or horseshoe-shaped gas masking element having a gas passage inside and having one or more rows of gas jetting ports or gas jetting grooves along the inner surface, and a gas communicating with the gas passage of this gas masking element to supply pressurized gas. It consists of a supply mechanism.

[Effect]

In this invention, the pressure gas supplied from the gas supply mechanism is ejected from the gas masking element,
This prevents the film formed on the substrate tube by thermal spraying from spreading on both sides, and forms a clear boundary.

〔Example〕

FIG. 1 is a perspective view showing an embodiment of this invention.
1 is a base tube, 11a, 11b, 11c, 11d
(Hereinafter, 11 will be simply used when there is no need to distinguish. The same applies to other symbols.) Each indicates a gas masking element, which is manufactured from a hollow heat-resistant structural material. These are gas supply supports 12a and 12 connected to the gas manifold 13.
b, 12c, and 12d, respectively;
Gas for gas curtain generation is supplied from here. Further, 14 is a support for the base tube 1, and 15 is a rotating shaft.

The axial spacing of the gas masking elements 11a to 11d is determined by the axial length of the solid oxide fuel cell element fabricated on the base tube 1. As shown in FIG. 4, the solid electrolyte fuel cell element constituting the battery stack includes electrodes 1a, 1c, solid electrolyte membrane 1
Consists of b. Therefore, by shifting the gas masking element 11 or the base tube 1 by a certain length in the axial direction and performing thermal spraying, the fabrication of the solid oxide fuel cell element and the series connection thereof are completed. For this,
As shown in FIG. 1, the gas manifold 13 is made movable and is equipped with a fine adjustment device 16 that can be moved in the axial direction. Alternatively, the same effect can be obtained even if this fine adjustment device 16 is installed on the rotating shaft 15 that supports the base tube 1. Note that 16a is an adjustment screw, 17 is a rail for moving the gas manifold 13, 18 is a gas supply port, and 19 is a base.

2a, b, c are perspective views showing details of various embodiments of the gas masking element 11 of FIG. 1; FIG.

Inside the gas masking element 11, a gas passage 21 is formed as shown in FIG. 2a, and gas outlets 22 for creating a gas curtain are provided in two rows along its inner surface. Alternatively, the gas ejection grooves 23 may be provided in two rows along the inner surface as shown in FIG. 2b. FIG. 2c shows an example in which the gas supply support 12a is provided at the bottom. The gas supplied from the gas supply support 12a cools the gas masking element 11 and is ejected from the gas outlet 22 or the groove 23 to the outside to create a gas curtain. The width of the opening 24 of the gas masking element 11 can be sized according to the outer diameter of the base tube 1.

In each of the above embodiments, the gas ejection ports 22 and the gas ejection grooves 23 are provided in two rows, but they may also be provided in one or two rows.

Thus, the gas masking elements 11 shown in FIGS. 2a, b, c, in part, rectify the flow of spray particles along the wall in the flow direction, reducing diffusion. Further, the gas curtain exhausts the thermal spray particles that are about to spread, thereby preventing the spray particles from spreading. Furthermore, the gas masking element 11 is cooled by passing gas thereinto and is prevented from deforming or breaking. Due to these effects, a film 31 with clear boundaries can be formed as shown in FIG. 3, and the distance between the films 31 can be improved by one order of magnitude to 0.5 mm.

In addition, the gas masking element 11 is shown in FIGS.
In addition to the horseshoe shape shown in the figure, a semicircular shape or a shape similar to this may also be used.

〔Effect of the invention〕

As described above, the present invention provides a semicircular or horseshoe-shaped gas masking element having a gas passage therein and one or more rows of gas ejection ports or gas ejection grooves along the inner surface, and a gas masking element having a gas passage in the gas masking element. Since it consists of a gas supply mechanism that communicates with each other and supplies pressurized gas, the gap between adjacent membranes is small, which increases the number of solid electrolyte fuel cells that can be manufactured on the base tube and reduces the usage rate of the base tube. can be increased. Furthermore, the portion where the solid electrolyte fuel cell elements are connected in series can be shortened, and more generated power can be obtained. Furthermore, the interdiffusion of gas from this connection can be reduced,
It can improve the utilization rate of fuel and also
This method has the advantage of enabling continuous production of fuel cell stacks and greatly improving productivity.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing an embodiment of the present invention, Fig. 2 a, b, and c are all perspective views showing the general shape of the gas masking shown in Fig. 1, and Fig. 3 is a perspective view showing an embodiment of the present invention for thermal spraying. An explanatory diagram showing the shape of the membrane formed by the gas masking device, Fig. 4 is a side cross-sectional view schematically showing a solid electrolyte fuel cell, and Fig. 5 is a perspective view schematically showing the fabrication of a battery stack using the conventional slit method. 6 are side views showing the shape of a film formed by the slit method of FIG. 5. In the figure, 1 is a porous hollow ceramic tube, 11a
~11d are gas masking elements, 12a~12d
is a gas supply support, 13 is a gas manifold, 1
4 is a support body, 15 is a rotating shaft, 16 is a fine adjustment device,
17 is a moving rail, 21 is a gas passage, 22 is a gas outlet, 23 is a gas outlet groove, and 31 is a membrane.

Claims (1)

[Claims] 1. A semicircular or horseshoe-shaped gas masking element that has a gas passage inside and has one or more rows of gas ejection ports or gas ejection grooves along its inner surface, and communicates with the gas passage of this gas masking element to supply pressurized gas. A gas masking device for thermal spraying, comprising a gas supply mechanism.