JPH05166531A - Manufacture of solid electrolyte fuel cell - Google Patents

Abstract

PURPOSE:To surely and stably retain a porous substrate or electrode by arranging an auxiliary member on an inner wall of fitting hole of a hollow fine quality substrate, and fitting the porous substrate or electrode via this auxiliary member. CONSTITUTION:A porous air electrode substrate 3 is fitted to a fitting hole of a fine quality substrate 1 via an adhesive agent 6 being an auxiliary member. An electrolytic film 4 is formed on the substrate 3 by means of plasma spraying. Then, a fuel electrode film is formed on the electrolytic film 4 by means of gas flame spraying, thus completing a cell part 2. Next, a conductive member 7 is formed on the fine quality substrate 1 by means of plasma spraying or gas flame spraying so that the cell parts 2 are connected to each other in series as well as in parallel. After completion of a process on one surface, a similar process is applied to the other surface of the fine quality substrate 1 so as to obtain a solid electrolyte fuel cell. These substrates can be thereby stably fixed to predetermined positions of the fitting holes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a solid electrolyte fuel cell in which an electrochemical reaction is carried out to extract electric energy.

[0002]

2. Description of the Related Art Conventionally, an elongated annular porous material is provided on the surface of a supporting tube with an inner annular electrode, an outer annular electrode and an electrolyte therebetween, and the inner annular electrode penetrates through the outer annular electrode and the electrolyte. A first battery and a second battery provided with a conductive connecting member adjacent to each other in a selected section of the first battery, and the inner annular electrode of the first battery and the outer annular electrode of the second battery are
There is known a solid electrolyte fuel cell in which a conductive connecting member of a battery and a first battery and a second battery are connected in series through a metal felt arranged between the first battery and the second battery (JP-A-57-130381). See the bulletin).

[0003]

When a solid oxide fuel cell is put to practical use, high efficiency in power generation is a major issue, and therefore thinning of the cell is being studied from all aspects. As one of them, in order to make it easier to discharge the reaction products and to make it easier to take the fuel into the electrode, the support tube made of a porous material that supplies the fuel is made thin to achieve high efficiency in power generation. It is believed to be useful to

However, in the conventional solid electrolyte fuel cell, it is necessary to support electrodes, electrolytes, conductive connecting members, etc., and in the first battery, a battery connected in parallel or in series such as the second battery is used. Since it must be supported through metal felt, the support tube had to be thick enough to withstand some strength. In addition, the first battery, the second battery, and the like have to be connected in parallel or in series via metal felts, which has a problem that the solid electrolyte fuel cell cannot be easily assembled.

In order to solve these problems, the present applicant has previously made Japanese Patent Application No. 2-106610 to reduce the strength required for a support (a porous substrate or an inner electrode) to make the support thin. We have proposed a solid oxide fuel cell that achieves high efficiency in power generation and can be easily assembled, and a method of manufacturing the same.

Among them, in particular, a solid electrolyte fuel cell of the type shown in FIGS. 9 to 11 has a porous dense substrate or an electrode on one side arranged on a hollow dense substrate having a plurality of mounting holes, and its surface Shows the manufacturing method for forming the electrolyte, the other electrode, and the conductive member.

However, in the solid electrolyte fuel cell of the type shown in FIGS. 9 to 11, the mounting hole and the porous substrate or the electrode on one side are in the form of a fragile thin film. Therefore, it is difficult to mount without a gap, and there arises a problem that a gap is formed between the mounting hole and the porous substrate or the electrode. Therefore, in the formation of the electrolyte or the like in the subsequent steps, the placed porous substrate or electrode is attached at a position deviated from the predetermined position of the attachment hole, or when forming a film on this surface, the porous substrate or electrode is It moves in the mounting hole and causes problems such as damage to the film being formed.

Therefore, according to the present invention, the porous substrate or the electrode to be mounted at the predetermined position of the mounting hole can be securely and stably held, and the above problems can be solved. It is an object of the present invention to provide a manufacturing method of.

[0009]

As a result of earnest studies, the present inventor has found that an auxiliary material is provided on at least the inner wall of the attachment hole of the hollow dense substrate, and the porous substrate or the electrode can be attached through this. The present invention has been completed by finding that it is effective.

That is, according to the present invention, (1) an auxiliary material is provided on at least the inner wall of the mounting hole of a hollow dense substrate having a plurality of mounting holes, and the porous supporting substrate is provided through the auxiliary material. A method for manufacturing a solid electrolyte fuel cell, characterized by comprising mounting in a mounting hole, and then forming a plurality of battery parts and a conductive member for connecting adjacent battery parts on the porous support substrate, and (2) a plurality of mountings. An auxiliary material is arranged on at least the inner wall of the mounting hole of a hollow dense substrate having holes, and the porous electrode substrate made of either one of an air electrode and a fuel electrode is attached through the auxiliary material. A method for manufacturing a solid oxide fuel cell, which comprises mounting in a hole and then forming a conductive member for connecting a plurality of battery parts and adjacent battery parts on the porous electrode substrate.

As described above, according to the present invention, when the porous supporting substrate or the porous electrode substrate is installed on the hollow dense substrate having the mounting holes (see FIG. 7), the inner walls of the mounting holes 10 are mounted. It is a method for manufacturing a solid oxide fuel cell (hereinafter, simply referred to as SOFC), which is characterized in that it is carried out through an arranged auxiliary material.

The first type of battery part in the present invention is
It has a layered structure as shown in FIGS. 8 and 9, that is, one in which an electrolyte membrane and the other electrode film are laminated in this order on a porous substrate made of either one of the air electrode or the fuel electrode. The second type has a layer structure as shown in FIGS. 10 and 11, that is, an air electrode film (or a fuel electrode film), an electrolyte film, and a fuel electrode film on a porous substrate serving as a support. (Or an air electrode film) in this order.

Therefore, in the present invention, after the porous support substrate or the porous electrode substrate made of the electrode (air electrode or fuel electrode) material is attached to the attachment hole of the hollow dense substrate via the auxiliary material, plasma spraying is performed. , Gas flame spraying, C
By the dry method of VD or PVD, one electrode film, an electrolyte film, the other electrode film in the former, and an electrolyte film in the latter,
The battery portion is provided by sequentially forming the other electrode films.

The hollow dense substrate used in the present invention is preferably an electrically insulating ceramic material, for example, alumina, magnesia, or a mixture thereof is suitable. Yttria-stabilized zirconia (hereinafter referred to as YSZ) or the like is suitable for the electrolyte membrane, and LaMnO ₃ or LaCoO ₃ to which an alkaline earth metal is added is suitable for the air electrode for the porous electrode substrate and the electrode film. Cage,
Ni-zirconia cermet or the like is suitable for the fuel electrode.

The porous substrate serving as a support is preferably a porous ceramic material, for example, alumina, magnesia,
And mixtures thereof, stabilized zirconia, and the like are suitable, but it is more desirable if electronic conductivity can be imparted.

The auxiliary material used in the present invention is provided in the mounting hole of the hollow dense substrate by interposing between the inner wall of the mounting hole and the porous supporting substrate or the porous electrode substrate on which the battery portion is formed. The substrate is held reliably and stably.

In the present invention, as such an auxiliary material, an adhesive or a holding member that fits into the mounting hole can be used. 12 and 13 are examples of the holding member. FIG. 12 shows a bottom having a hole through which gas can freely pass, and FIG. 13 shows a bottom provided with a rib for reinforcement, both of which have a collar for locking at the peripheral edge of the mounting hole at the top. Part (see FIG. 6). Since the holding member has such a structure, even if there is a gap between the mounting hole of the hollow dense substrate and the porous substrate to be mounted therein, this holding member is fixed to the mounting hole, and the porous substrate is placed there. It is possible to surely and stably hold by fitting or mounting.

In the present invention, when the auxiliary material is an adhesive, it is formed by applying it so that it exists around the inner wall of the mounting hole. Preferably, as shown in FIG. 4, the adhesive 6 is also provided between the support member 8 provided in the hollow portion of the substrate 1 and the porous substrate so that the adhesive can be held more reliably.

The holding member is made of a heat resistant metal material such as a Ni-base super heat resistant alloy, and the adhesive is alumina.
A ceramic-based material that is stable and densified in an oxidation-reduction atmosphere, using silica, zirconia, or the like as a base material is preferable.
In this case, if an electrically conductive substance such as metal, cermet, or conductive ceramics is used, the adhesive acts as a collector electrode of the inner electrode, and heat transfer between the electrode portion and the dense substrate is also facilitated.

The conductive member is a material that has electronic conductivity and is stable in a redox atmosphere, and for example, a perovskite type oxide obtained by adding an alkaline earth metal to LaCrO ₃ is suitable. In this case, the conductive member and the adhesive can be made of the same material, and the adhesive and the conductive member can be configured at the same time.

Among the above SOFC components, the hollow dense substrate is produced by extrusion molding, and the porous electrode substrate and the porous supporting substrate are produced by the doctor blade method, powder pressing method, or the like.

Further, the electrode film, the electrolyte film, the conductive member, and the gas seal film are produced by a dry method such as plasma spraying, gas flame spraying, CVD, PVD, or a wet method such as a screen printing method or a dipping method. It is performed by a film forming technique such as. In the present invention, film formation by a dry method is particularly preferable.

[0023]

In the SOFC of the present invention, the case where the porous electrode substrate of the battery part is the air electrode will be described. By holding SOFC at about 1000 ° C., supplying oxygen to the hollow portion of the dense substrate and supplying hydrogen to the outside of the dense substrate on the fuel electrode side, an electrochemical reaction occurs and electric energy is generated.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view showing the outline of the SOFC as a whole, and FIGS. 2 and 3 are sectional views taken along the line YY and XX, respectively.

The dense substrate 1 is formed by extruding alumina as a raw material, and then a battery portion mounting hole is appropriately opened.
It is manufactured by firing at 00 ° C to 1700 ° C.

Separately, using La _0.8 Sr _0.2 MnO ₃ as a raw material, a green film is formed by a doctor blade method, cut with a cutter, and then baked at 1200 ° C. to 1500 ° C. to obtain a porous air electrode substrate 3.

The porous air electrode substrate 3 is attached to the mounting hole of the dense substrate 1 with an adhesive 6 as an auxiliary material.

Next, the porous air electrode substrate 3 is masked at the current extraction portion, and yttria-stabilized zirconia is sprayed by the plasma spraying method to form the electrolyte membrane 4.

Further, masking is applied on the electrolyte membrane 4,
NiO-YSZ is sprayed by a gas flame spraying method to form a fuel electrode film, and the cell unit 2 is completed.

Next, the dense substrate is masked,
The conductive member 7 is formed by spraying LaMgCrO ₃ by the plasma spraying method or the gas flame spraying method, and the battery parts 2 are connected in series and in parallel.

After the completion of one surface, the other surface of the dense substrate 1 is subjected to the same operation as described above to manufacture the SOFC. Before forming the conductive member 7, alumina may be sprayed by a plasma spraying method to form a gas seal film.

Next, a second embodiment will be described with reference to FIG.

FIGS. 5 (a) to 5 (d) illustrate the SOFC manufacturing process.

In this example, (a) the adhesive 6 as an auxiliary material is applied to the mounting hole of the dense substrate 1 on the inner peripheral surface of the hole and the supporting member 8 provided in the hollow portion of the substrate 1, This is a mode in which the porous air electrode substrate 3 is attached, then (b) a conductive member 7 is provided between adjacent battery parts, and (c) an electrolyte membrane 4 and (d) a fuel electrode membrane 5 are sequentially provided. The other materials used, the manufacturing method, and the like are the same as those in the above embodiment.

Power generation can be performed by keeping the completed SOFC at about 1000 ° C., supplying oxygen to the hollow portion 9 of the dense substrate 1 and supplying hydrogen to the fuel electrode side.

Although an example of an adhesive is shown as an auxiliary material, as shown in FIG. 6, the holding member 14 as shown in FIGS.
FC can be manufactured. Further, the shapes of the dense substrate 1, the battery portion 2, the masking, etc. are not limited to those in the above-described embodiment, and other shapes may be used. In the SOFC having a structure using the porous supporting substrate for the battery portion 2, Even if the fuel electrode is provided on the hollow portion 9 side, the effect of the above manufacturing method is the same.

[0038]

As described in detail above, according to the present invention,
Between mounting holes created by machining, dimensional error of porous support substrate and porous electrode substrate, or dimensional error due to thermal contraction generated by firing porous support substrate and porous electrode substrate The gap can be corrected by interposing an auxiliary material, and at the same time, these substrates can be fixed to the predetermined positions of the mounting holes in a stable state. Further, the film arranged on the fixed substrate is a thin film of about 200 μm, but in the formation of this thin film, since the fixed lower layer is stable, it can be formed without any trouble. In particular, it is more effective when this film formation is performed by a dry method.

[Brief description of drawings]

FIG. 1 is a plan view showing the outline of an SOFC according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line YY of FIG.

FIG. 3 is a sectional view taken along line XX of FIG.

FIG. 4 is an explanatory sectional view showing the outline of an SOFC according to a second embodiment of the present invention.

FIG. 5 is an explanatory diagram of each step of the second embodiment of the present invention.

FIG. 6 is an explanatory view when a holding member is used as an auxiliary member in the present invention.

FIG. 7 is a perspective view in which a partial internal structure of a hollow dense substrate having a battery portion mounting hole is omitted.

FIG. 8 is a perspective view of a battery unit using a porous air electrode substrate.

FIG. 9 is a perspective view of a cell unit using a porous fuel electrode substrate.

FIG. 10 is a perspective view of a battery part in which an air electrode, an electrolyte, and a fuel electrode are laminated in this order on a porous support substrate.

FIG. 11 is a perspective view of a battery unit in which a fuel electrode, an electrolyte, and an air electrode are laminated in this order on a porous support substrate.

FIG. 12 is a perspective view illustrating an example of a holding member as an auxiliary material used in the present invention.

FIG. 13 is a perspective view illustrating another example of the same.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Dense substrate 2 ... Battery part 3 ... Porous air electrode substrate 4 ... Electrolyte film 5 ... Fuel electrode film 6 ... Adhesive 7 ... Conductive member 8 ... Supporting member 9 ... Hollow part 10 ... Battery part mounting hole 11 ... Porous fuel electrode substrate 12 ... Air electrode film 13 ... Porous support substrate 14 ... Holding member

Claims (4)

[Claims] 1. A hollow dense substrate having a plurality of mounting holes, at least an auxiliary material being disposed on an inner wall of the mounting hole, and a porous supporting substrate being mounted in the mounting hole through the auxiliary material, and then the A method for manufacturing a solid electrolyte fuel cell, comprising forming a conductive member that connects a plurality of battery parts and adjacent battery parts on a porous support substrate. 2. An auxiliary material is provided on at least the inner wall of the mounting hole of a hollow dense substrate having a plurality of mounting holes, and an electrode material of either one of an air electrode or a fuel electrode is provided through the auxiliary material. And a conductive member for connecting a plurality of battery parts and adjacent battery parts is formed on the porous electrode substrate, and a method for manufacturing a solid electrolyte fuel cell, comprising: .. 3. The method for producing a solid electrolyte fuel cell according to claim 1, wherein the formation of the cell portion and the formation of the conductive member are performed by a plasma spraying method, a gas flame spraying method, a CVD or a PVD dry method. .. 4. The method for producing a solid oxide fuel cell according to claim 1, wherein the auxiliary material is a holding member made of an adhesive or a heat resistant metal material.