JP2011209129A - Method and device for testing bending of power generation cell - Google Patents

Abstract

By applying a uniform load to a disk-shaped power generation cell, not only the bending strength of the central portion but also the bending strength of the peripheral portion can be evaluated, and power generation cells with low bending strength can be eliminated. A bending strength test method and a bending strength test apparatus for a power generation cell are provided.
A method for evaluating the bending strength of a flat power generation cell, wherein the power generation cell is disposed between a convex jig having a cylindrical surface and a concave jig having a cylindrical surface. The bending strength of the power generation cell 1 as a whole is evaluated by bringing the cylindrical surface 2a of the convex jig 2 and the cylindrical surface 3a of the concave jig 3 into close proximity and bending.
[Selection] Figure 1

Description

  The present invention relates to a power generation cell bending strength test method and a bending test apparatus for evaluating the bending strength of a power generation cell made of ceramics or cermet.

  For example, in a conventional general solid oxide fuel cell, a fuel electrode is integrally formed on one surface of a fixed electrolyte layer serving as a support, and an air electrode layer is integrally formed on the other surface. A disc-shaped power generation cell is used.

Here, as the solid electrolytic layer, yttria-added stabilized zirconia (YSZ), (LaSr) (GaMg) O ₃ , (LaSr) (GaMgCo) O ₃ , (LaSr) (GaMgNi) O ₃ , (LaSr) A lanthanum gallate-based (LaGaO ₃ -based) material having a high oxygen ion conductivity such as (GaMgFe) O ₃ is used.

Further, a metal such as Ni or Co or a cermet such as Ni—YSZ, Co—YSZ, Ni—GDC, or Ni—SDC is used as the fuel electrode layer, and LaMnO ₃ , LaCoO ₃ , SmCoO are used as the air electrode layer. ₃ etc. are used.
Incidentally, the solid electrolyte layer has a thickness dimension of 150 μm or more, and the fuel electrode layer and the air electrode layer are respectively formed on the surface of the solid electrolyte layer with a thickness dimension of 20 to 30 μm.

  The power generation cell having such a configuration is formed by laminating a plurality of sheets together with a separator and a current collector for supplying an oxidant gas and a fuel gas to the power generation cell, and in a state where a predetermined load is applied. It generates power in a temperature atmosphere.

  By the way, in this type of power generation cell, it is a thin disk-shaped member made of ceramics having a thickness of 150 μm, so that it has poor elasticity and receives a large thermal pressure between room temperature and about 800 ° C. It is. For this reason, when assembling a fuel cell using a power generation cell made of the above ceramic material, a plurality of test pieces are taken for each lot of the material and subjected to a material bending strength test to obtain an average strength and a Weibull coefficient (shape). By calculating the coefficient, the material bending strength of the material in the lot is evaluated.

On the other hand, a material bending strength test method for a general ceramic material is specified in JIS R1601. As shown in FIG. 3 (a), the lower fulcrum of the test piece 4 cut into a predetermined dimension (4 ^W × 36 ^L or more × 3 ^t , unit mm (hereinafter the same)). 5 and 5 and performing a three-point bending test by three points of the upper fulcrum 6 to which a load is added at the center, as shown in FIG. A four-point bending test is performed using four upper fulcrums 6 and 6 that apply the same load between the two central points.

Therefore, conventionally, taking into account the above standards, a square sheet (70 × 20) is cut out from a ceramic green sheet as a material by using a ruler and a cutter, or by using a die having a square blade. Then, this was sintered to produce a square plate (50 × 15 × 0.1 ^t ) test piece, and the test piece was subjected to the above-mentioned 3-point bending test or 4-point bending test.

  However, when cutting out a square sheet from a green sheet, if a ruler and a cutter are used, the cutter's blade is not sharp or an operator with a low level of skill does not move the cutter continuously. When the cutter is interrupted on the way or when the cutter is locally deviated from the ruler, the cutting edge of the obtained rectangular sheet is likely to be chipped. In addition, when a die having a square blade is used, when the blade is pressed against the green sheet and punched as it is, chipping due to a similar cut defect is likely to occur due to force imbalance or the like. There is a tendency.

  For this reason, in a general three-point bending test method, when a stress is applied to a portion to which a load is applied, if there is a defect such as a crack in the portion to which the load is applied or the periphery thereof, this defect Since stress concentrates on the portion and breaks, the bending strength can be evaluated by this test method. However, when there is a defect in the peripheral edge where chipping is most likely to occur, stress does not act on the peripheral edge, so that there is a problem that the bending strength cannot be evaluated by this test method.

  Further, in a ceramic material having a large variation in strength, an average strength can be evaluated by performing a general four-point bending test method. However, even in a lot having an average strength evaluated by this test method, a low-strength power generation cell may be included because of a possibility of including a low-strength power generation cell due to a defect or the like generated in each peripheral portion. Need to be eliminated without making it a product. However, as in the three-point bending test, there is a problem in that the bending strength cannot be evaluated when there is a defect at the peripheral edge where the chipping is most likely to occur without stress.

  The present invention has been made in view of such circumstances, and by applying a uniform load to the disk-shaped power generation cell, not only the bending strength of the central portion but also the bending strength of the peripheral portion is evaluated, and the bending is evaluated. It is an object of the present invention to provide a bending strength test method and a bending strength test apparatus for a power generation cell that can eliminate power generation cells having low strength.

  In order to solve the above-mentioned problem, the bending strength test method for a power generation cell according to claim 1 is a method for evaluating the bending strength of a flat power generation cell, and includes a convex jig having a cylindrical surface and a cylindrical surface. The power generating cell is disposed between the concave jig having the curved shape and the cylindrical surface of the convex jig and the cylindrical surface of the concave jig are brought close to each other, thereby bending the entire power generating cell. It is characterized by evaluating.

  The bending strength test method for a power generation cell according to claim 2 is a method for evaluating the bending strength of a flat power generation cell, and has a cylindrical surface with a radius of curvature corresponding to the bending strength of the power generation cell. The power generation cell is arranged between a convex jig and a concave jig having a cylindrical surface with the radius of curvature, and the cylindrical surface of the convex jig and the cylindrical surface of the concave jig are brought into close proximity to bend. Thus, the strength of the entire power generation cell is evaluated, and power generation cells having low strength are excluded.

  According to a third aspect of the present invention, there is provided a bending strength test apparatus for a power generation cell, which is a device for evaluating a bending strength by arranging a flat power generation cell between a pair of jigs to bend the power generation cell. The tool is characterized by being formed of a male mold having a convex cylindrical surface and a female mold having a concave cylindrical surface.

  Further, the invention described in claim 4 is the power generation cell bending strength test device according to claim 3, wherein the radius of curvature of the cylindrical surface is the same as that of the circular flat plate cell in which the power generation cell uses a lanthanum gallate electrolyte. In this case, the thickness is 600 to 800 times the thickness.

  According to this invention of Claims 1-4, it arrange | positions between the convex jig | tool which has a cylindrical surface, and the concave jig | tool which has a cylindrical surface, and the flat power generation cell is a cylinder of the said convex jig | tool. Since the surface and the cylindrical surface of the concave jig are brought close to each other and curved by applying a load, even if a defect such as a chip occurs at the peripheral edge, the stress concentrates on the defective part and breaks. Is done. Thereby, the bending strength of the whole flat power generation cell can be evaluated.

  According to this invention of Claim 2, it has a convex-shaped jig | tool which has a cylindrical surface of the curvature radius according to the bending strength of this power generation cell, and the cylindrical surface of the said curvature radius. Since it is arranged between the concave jig, and the cylindrical surface of the convex jig and the cylindrical surface of the concave jig are brought close to each other and curved by applying a load, the above according to the bending resistance strength An equal load is applied by the curvature radius, and the entire flat power generation cell is curved. As a result, when a uniform stress acts on the entire power generation cell and a defect such as a chip occurs in the power generation cell, the stress concentrates on the defective portion and the power generation cell is destroyed. As a result, it is possible to evaluate the bending strength of the entire flat plate-like power generation cell and eliminate power generation cells having low strength.

  According to this invention of Claim 3, a pair of jig | tool used for the apparatus which curves a flat power generation cell and evaluates bending strength is a male type | mold which has a convex cylindrical surface, and a concave cylindrical surface. Therefore, the plate-shaped power generation cell is disposed between the pair of jigs, the cylindrical surfaces of the respective molds are brought close to each other, and a load is applied thereto. Curved along the male convex cylindrical surface and the female concave cylindrical surface. Thereby, a load acts on the whole power generation cell, and the bending strength of the whole plate-shaped power generation cell can be evaluated by uniform stress.

  According to the fourth aspect of the present invention, the radius of curvature of the male convex cylindrical surface and the female concave cylindrical surface is the same as that of the circular flat plate cell in which the power generation cell uses a lanthanum gallate electrolyte. In this case, since the thickness dimension is 600 to 800 times, when the material and the thickness dimension are the same, the flat plate-shaped power generation cell is simply disposed between the pair of jigs. A uniform stress can be applied to the entire power generation cell. Thereby, the bending strength of the flat power generation cell can be easily evaluated.

It is the schematic which shows one Embodiment of the bending test apparatus of the electric power generation cell of this invention. BRIEF DESCRIPTION OF THE DRAWINGS The schematic explaining the bending test method by the bending test apparatus of the power generation cell of this invention is shown, (a) is the state which has arrange | positioned the flat power generation cell to a pair of jig | tool, (b) The center of a flat power generation cell A state in which a load is applied to the part, (c) is a state in which the load is applied to the entire flat plate-shaped power generation cell. The schematic explaining the bending test method of a JIS specification is shown, (a) is a 3 point | piece bending test method, (b) is a 4 point | piece bending test method.

1 to 2 show an embodiment of a bending test method and bending test apparatus for a power generation cell according to the present invention.
As shown in FIG. 1, the bending test apparatus for a power generation cell according to the present invention includes a male mold (convex jig) 2 having a convex cylindrical surface 2a and a female mold (concave jig) having a concave cylindrical surface 3a. ) 3 is generally configured with the cylindrical surfaces 2a and 3a facing each other.

Further, the power generation cell 1 used in the apparatus includes stabilized zirconia (YSZ), (LaSr) (GaMg) O ₃ , (LaSr) (GaMgCo) O ₃ , (LaSr) in which yttria is added to the solid electrolytic layer. A lanthanum gallate-based (LaGaO ₃ -based) material having high oxygen ion conductivity such as () (GaMgNi) O ₃ , (LaSr) (GaMgFe) O ₃ ), or a ceria (GDC) material added with gadolinium is used.

Further, a metal such as Ni or Co or a cermet such as Ni-YSZ, Co-YSZ, Ni-GDC, or Ni-SDC is used as the fuel electrode layer, and LaMnO ₃ , LaCoO ₃ , SmCoO are used as the air electrode layer. ₃ etc. are used. Further, the solid electrolyte layer has a thickness dimension of 150 μm or more, and the fuel electrode layer and the air electrode layer are each formed on the surface of the solid electrolyte layer with a thickness dimension of 20 to 30 μm.

  The convex cylindrical surface 2 a of the male mold 2 and the concave cylindrical surface 3 a of the female mold 3 are formed with a radius of curvature corresponding to the bending strength of the flat power generation cell 1. In the case of a circular plate cell using a lanthanum gallate electrolyte, this radius of curvature is formed 600 to 800 times the thickness dimension.

This is based on the three-point bending test method stipulated by JIS shown in FIG. 3 (a), and the distance between the lower fulcrum 5 and 5 is changed with respect to the thickness of the power generation cell 1, and the displacement at the maximum bending stress. The radius of curvature is calculated based on the following data for which the amount was obtained.
This radius of curvature varies depending on the elastic modulus of the material.

<Experimental example>

  In order to perform a bending strength test of the power generation cell 1 using the power generation cell bending strength test apparatus of the present embodiment having the above-described configuration, first, as shown in FIG. 2 (a), a concave cylindrical surface 3a is provided. A flat power generation cell 1 is disposed in the center of the female die 3. Next, the male mold 2 is brought close to the female mold 3 and a load is applied to curve the power generation cell 1. At this time, as shown in FIG. 2B, the top of the convex cylindrical surface 2a of the male mold 2 comes into contact with the central portion of the power generating cell 1, and stress is applied to the central portion to generate the power generating cell 1. Begins to curve. As the male mold 2 approaches the female mold 3, the stress acting on the central portion of the power generation cell 1 is dispersed to the peripheral portion. At this time, if a defect such as a chip occurs in the power generation cell 1, stress concentrates on the defective portion, and the power generation cell 1 is destroyed. Thereby, the bending strength of the power generation cell 1 can be evaluated.

  In addition, when the convex cylindrical surface 2a of the male mold 2 and the concave cylindrical surface 3a of the female mold 3 are formed to have a radius of curvature corresponding to the bending strength of the power generation cell 1, FIG. In this manner, the load is applied and the male mold 2 is brought close to the female mold 3 and bent to the thickness dimension of the power generation cell 1. At this time, an equal load is applied to the power generation cell 1 between the cylindrical surfaces 2a and 3a of the respective molds, so that a uniform stress acts on the entire power generation cell 1. Thereby, when the power generation cell 1 has a defect, stress concentrates on the defective portion, and the power generation cell 1 is damaged. Thereby, bending strength can be evaluated by curving the power generation cell 1 with a radius of curvature corresponding to the bending strength of the power generation cell 1.

  According to the bending test method and the bending test apparatus for the power generation cell according to the above-described embodiment, the flat power generation cell 1 is placed between the convex jig 2 having the cylindrical surface 2a and the concave jig 3 having the cylindrical surface 3a. When the cylindrical surface 2a of the convex jig 2 and the cylindrical surface 3a of the concave jig 3 are placed close to each other and curved by applying a load, there is a defect such as a chip at the peripheral edge. However, stress concentrates on the defective part and is destroyed. Thereby, the bending strength of the whole flat power generation cell 1 can be evaluated, and a power generation cell with low intensity | strength can be excluded.

  Also, the flat power generation cell 1 is formed by using a convex jig 2 having a cylindrical surface 2a having a radius of curvature corresponding to the bending strength of the power generation cell 1, and a concave jig 3 having a cylindrical surface 3a having the radius of curvature. The curvature radius according to the bending resistance strength is set so that the cylindrical surface 2a of the convex jig 2 and the cylindrical surface 3a of the concave jig 3 are brought close to each other and curved by applying a load. The flat power generation cell 1 as a whole is bent by the equal load according to the above, and a uniform stress is applied to the entire power generation cell 1. As a result, when a defect such as a crack has occurred in the power generation cell 1, the stress concentrates on the defective portion and the power generation cell 1 is destroyed. As a result, the bending strength of the entire flat power generation cell 1 can be evaluated without variation, and power generation cells having low strength can be eliminated.

  The pair of jigs 2 and 3 used in the apparatus for bending the flat power generation cell 1 to evaluate the bending strength includes a male mold 2 having a convex cylindrical surface 2a and a female having a concave cylindrical surface 3a. Since it is formed by the mold 3, the plate-shaped power generation cell 1 is disposed between the pair of jigs 2 and 3, the cylindrical surfaces 2 a and 3 a of the respective molds are brought close to each other, and a load is applied. Accordingly, the curved shape is curved along the convex cylindrical surface 2 a of the male mold 2 and the concave cylindrical surface 3 a of the female mold 3. Thereby, the equal load is applied to the entire power generation cell 1, and the bending strength of the entire flat power generation cell 1 can be evaluated by uniform stress, and the power generation cells having low strength can be eliminated.

  Further, when the radius of curvature of the convex cylindrical surface 2a of the male mold 2 and the concave cylindrical surface 3a of the female mold 3 is the thickness of the power generation cell 1 when the power generation cell 1 is a circular plate cell using a lanthanum gallate electrolyte, Since it is 600 to 800 times the size, when the material and thickness are the same, the flat power generation cell can be obtained by simply placing the flat power generation cell 1 between the pair of jigs 2 and 3. Uniform stress can be given to the whole 1. Thereby, the bending strength of the flat power generation cell 1 can be evaluated easily.

  In the above-described embodiment, only when the convex cylindrical surface 2a of the male mold 2 and the concave cylindrical surface 3a of the female mold 3 are formed with a radius of curvature corresponding to the bending strength of the flat power generation cell 1. Although explained, it is not limited to this, For example, the convex cylindrical surface 2a and the concave cylindrical surface 3a can be made into the curvature radius corresponding to the intensity | strength reference | standard of the electric power generation cell 1.

  It can utilize for the bending test of the electric power generation cell used for a fuel cell.

1 Power generation cell 2 Convex jig (male)
2a cylindrical surface 3 concave jig (female)
3a Cylindrical surface 4 Test piece 5 Lower fulcrum 6 Upper fulcrum

Claims (4)

A method for evaluating the bending strength of a flat power cell,
The power generation cell is disposed between a convex jig having a cylindrical surface and a concave jig having a cylindrical surface,
A bending strength test method for a power generation cell, wherein the bending strength of the whole power generation cell is evaluated by bringing the cylindrical surface of the convex jig and the cylindrical surface of the concave jig close to each other and bending. A method for evaluating the bending strength of a flat power cell,
A convex jig having a cylindrical surface with a radius of curvature corresponding to the bending strength of the power generation cell;
The power generation cell is disposed between a concave jig having a cylindrical surface of the curvature radius,
Power generation characterized in that the cylindrical surface of the convex jig and the cylindrical surface of the concave jig are brought close to each other to bend, thereby evaluating the strength of the entire power generation cell and eliminating power generation cells having low strength. Cell bending strength test method. A flat power generation cell is placed between a pair of jigs to bend and evaluate bending strength,
The pair of jigs is formed of a male mold having a convex cylindrical surface and a female mold having a concave cylindrical surface, and a bending strength testing apparatus for a power generation cell.   4. The power generation according to claim 3, wherein the radius of curvature of the cylindrical surface is 600 to 800 times the thickness when the power generation cell is a circular flat plate cell using a lanthanum gallate electrolyte. Cell bending strength testing equipment.

Images