JP3366866B2 - Fuel cell separator and mold for forming bridge type corrugated sheet used therein - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell separator having an improved bridge type corrugated plate for pressing and supporting a cell structure.

[0002]

2. Description of the Related Art The structure of a conventional fuel cell, for example, Japanese Unexamined Patent Publication No.
Japanese Patent No. 129022 discloses that carbon dioxide is formed between a cathode electrode that generates carbonate ions from air and an oxidant gas containing carbon dioxide as a main component, and an anode electrode that reacts carbonate ions with hydrogen in fuel gas to generate carbon dioxide gas and water vapor. A cell structure sandwiching an electrolyte plate through which ions pass is arranged between partition plates, and a bridge type corrugated plate is arranged in the gas passage for flowing the oxidant gas formed between the partition plate and both electrodes, and the cell structure is moved up and down. The fuel cell which is pressed and supported between the partition plates is described.

FIG. 1 shows a conventional method for manufacturing a bridge type corrugated plate 1.
5, FIG. 16, FIG. 17, and FIG. The substrate 1A made of a metal member is formed with a pair of upper and lower cutout grooves 1H facing each other, and a plurality of a pair of cutout grooves 1H are formed at predetermined intervals along the longitudinal direction of the substrate 1A. Called A. Further, the cutout groove 1H of the first bridge row A
The cutout groove 1H of the second bridge row B is formed between them via the intermediate portion C. That is, the bridge portion of the first bridge row A and the second bridge row A
The bridge portion of the bridge row B is not arranged in a straight line as shown in the drawing, but is arranged in a zigzag pattern with a predetermined width offset.

Then, a U-shaped die is pressed against the substrate 1A between the pair of notched grooves 1H by a press machine to form the substrate 1
A bridge portion 1B protruding in one direction from A is formed. In other words, the substrate 1A is also a current collecting surface 1F that contacts the cathode electrode and the anode electrode. When the substrate 1A is pressed by the press machine, the tip of the bridge portion 1B is formed in a U shape.

[0005]

However, the substrate 1
In the current collecting surfaces 1F ₁ and 2F ₂ between the bridge portion 1B and the bridge portion 1B in the longitudinal direction of A, when the bridge portion 1B is pressed by the mold of the press machine, the current collecting surfaces 1F ₁ and 2F ₂ are gathered. The entire structure forms a deformed bridge portion 1B 'due to the influence of the pressure rather than the middle C. The deformation of the bridge portion 1B 'occurs due to the fact that the current collecting surfaces 1F ₁ and 2F ₂ are connected to the pressed portion, the pressing force difference at the time of pressing, the dimensional error of the cutout groove 1H, and the like.

As a result, the deformation of the bridge portion 1B 'causes a difference and a variation in the height dimension H with respect to the middle C. Figure 1
9, the deformation of the bridge portion 1B 'will be described using a numerical value that is an index of the height, in which a low-height portion occurs along the row. In the figure, the current collecting surface 1F of the cell structure 1 composed of the middle C, the second bridge row B and the third bridge row D is divided into a grid shape as shown in the drawing, and a partition plate is provided on each side of the grid. A numerical value that is an index of the height of the grid is given, and the average value of the four sides of the grid is used as the representative value of the grid height. At this time, 1 is made to correspond to the side having the cutout groove 1H of the lattice for forming the bridge portion 1B, and the side is connected to the current collecting portion 1F and is affected by the deformation due to pushing, for example, the current collecting surface 1
-1 is associated with F ₁ and 2F ₂ . At this time, the height representative value of each lattice on the plane is a value surrounded by a circle in FIG. 19, which is 1 at the maximum and 0 at the minimum.

As described above, the deformation of the bridge portion 1B 'causes a variation in height dimension, and the contact pressure for contacting the cathode electrode and the anode electrode on the current collecting surface 1F becomes strong and weak, and is pressed by a uniform contact pressure. In addition to increasing the voltage drop between the electrode and the current collecting surface by concentrating the current on the current collecting surface 1F having a strong contact pressure, the temperature locally rises and oxygen gas The electrolyte plate may corrode the bridge type corrugated plate 1, wear the electrolyte, and shorten the life of the fuel cell unit.

It is an object of the present invention to provide a fuel cell separator in which the contact pressure on the current collecting surface is equalized and the life of the fuel cell is improved.

[0009]

In order to achieve the above-mentioned object of the present invention, the fuel cell separator according to claim 1 of the present invention produces carbonate ions from an oxidant gas mainly composed of air and carbon dioxide gas. a cathode electrode for generating an electrolyte plate for passing the carbonate ion, and a cell structure composed of an anode electrode for generating carbon dioxide and water vapor are reacted hydrogen carbonate ion and a fuel gas, when storing the cell configuration co
A partition plate for separating the oxidant gas and the fuel gas, and
Placed in the gas passage formed between the cut plate and the cell configuration
Composed of a bridge-type corrugated plate that presses and supports the cell structure
In the fuel cell separator, a substrate between the notch groove and the notch groove facing each other is provided on the substrate of the bridge type corrugated plate.
A first bridge portion 10B adjacent to the first bridge portion 10B, which is provided with a bridge portion protruding toward the cut plate Notch groove 10 between the second bridge portion 11B and
H and 11H are configured so that they do not face each other in the same direction.

In order to achieve the above object of the present invention, in a fuel cell separator according to claim 2 of the present invention,
The first bridge portion 10B and the first bridge of the first bridge row A.
The second bridging of the second row bridge row B with the ridge portion 10B
Specially, it is arranged so that a part of the edge portion 11B is wrapped.
It is described in claim 1 as a characteristic.

In order to achieve the above object of the present invention, in a fuel cell separator according to claim 3 of the present invention,
A bridge row in which a plurality of the bridge portions 10B, 11B are arranged in a row is provided on the board 1A of the bridge type corrugated plate, which includes a bridge portion projecting the board 1A between the notched grooves facing each other toward the partition plate. Multiple columns A, B,
Notch grooves 10H, 1 arranged in D and E, between the first bridge portion 10B and the second bridge portion 11B adjacent to each other in each bridge row.
1H does not face each other in the same direction, and the cutout grooves 10H , 11H of the first and second bridge portions 10B, 11B of each bridge row are arranged in the direction perpendicular to the longitudinal direction of the substrate 1A and in the same direction as the longitudinal direction. To do.

In order to achieve the above object of the present invention, in a fuel cell separator according to claim 4 of the present invention,
The structure according to any one of claims 1 to 3, wherein an R surface is formed at an end of the cutout groove.

In order to achieve the above object of the present invention, it is used for a fuel cell separator according to claim 5 of the present invention.
In a die for molding a bridge type corrugated sheet , the bridge
A notch groove and a notch groove facing each other on the corrugated plate substrate 1A.
It is equipped with a bridge part that protrudes the board 1A between
A plurality of bridge parts 10B and 11B are arranged in a line.
Mold for forming a bridge row in a plurality of rows A and B with a gap
And the die Z is in a direction perpendicular to the longitudinal direction of the substrate 1A.
A first protrusion having a pair of first notches formed in
One convex portion was formed in the same row as the longitudinal direction of the substrate 1A.
A first bristle including a second convex portion having a pair of second notch grooves.
And the base and are arranged so as to correspond to the first row and the first projection.
A pair of second notch grooves formed in the same direction as the longitudinal direction of the plate 1A
And a second convex portion having the same shape as the first convex portion in the same row as the second convex portion.
And the substrate 1 is arranged so as to correspond to the second convex portion of the row of rows.
A pair of first notch grooves formed in the direction perpendicular to the longitudinal direction of A
A second bridge row consisting of a first convex portion and a unit consisting of
It is about constructing a knit .

[0014]

[0015]

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to FIGS. FIG. 1 shows a state in which two cell configurations 10 are stacked. In the figure, 11A and 11C are anode and cathode electrodes, and 12 is an anode electrode 11A.
The electrolyte plate impregnated with the electrolyte sandwiched between the cathode electrode 11C and the cathode electrode,
1A, a cathode electrode 11C, and an electrolyte plate 12. Reference numeral 13 is a partition plate in which the cell structure 1 is arranged.

A gas passage 14 for supplying a fuel and an oxidant gas is formed between the cathode electrode 11C and the partition plate 13, and a supply port 14A and an outlet 14B are provided at both ends of the gas passage 14, respectively. It communicates with a manifold 16 penetrating the seal portion 15. Further, another gas passage penetrates from the front side of the paper to the back side.

The cell structure 10 is provided in the gas passage 14 with a partition plate 1.
A bridge-type corrugated plate 1 that presses and supports the three is interposed.
The structure of the bridge type corrugated plate 1 is the bridge portion 1B and the current collecting surface 1.
The bridge portion 1B projects in one direction from the current collecting surface 1F, that is, toward the partition plate 13 side.

The structure of the bridge type corrugated plate 1 will be described. That is, the bridge type corrugated sheet 1 is formed by forming the facing notch grooves 1 formed on the current collecting surface 1F of the bridge type corrugated sheet 1 supporting the cell structure 10.
H and a bridge portion 1B formed by pressing the current collecting surface 1F between the cutout grooves toward the partition plate. The plurality of bridge portions 1B are arranged in a row with a gap. One of the plurality of bridge portions is referred to as a first bridge row A. Second to fourth bridge rows B, D, E are arranged from the first bridge row A through the intermediate row C, respectively. The cutout groove 1H penetrates the flat plate of the bridge type corrugated plate 1.

The first bridge portion 10B of the second bridge row B
The notch groove 11H is arranged corresponding to the second bridge portion 11 and the notch groove 11H of the first bridge row A via the current collecting surface 1F ₁ . The bridge portions 10B and the cutout grooves 11H of the third bridge row D and the fourth bridge row E are also arranged in the same manner as described above. In this way, the adjacent bridge portion 10B and cutout groove 10H and the second bridge portion 11B and cutout groove 11H are configured so as not to face each other in the same direction.

The effect of this configuration will be described with reference to FIG. In the figure, each grid is a second and a third bridge row B,
D, the intermediate row C and the spacing between the bridges in the row. At this time, a value of 1 is given to the notched side of the grid or a value of -1 to the side continuous with the current collecting surfaces 1F ₁ and 2F _{2 by} the same method as in FIG. 19, and the average value is used to represent the height of the grid. Then, the value is in the range of 0.5 to 1 as indicated by the circle in the figure. On the other hand, in FIG. 19, this value was in the range of 0 to 1.

As is clear from FIG. 4, the first bridge portion 10B and the cutout groove 10H and the second bridge portion 11B and the cutout groove 11H which are adjacent to each other are configured so as not to face in the same direction. . When forming the first bridge portion 10B, the substrate 1A is pressed by a mold between the cutout grooves 10H. The range of the deformation due to the pressing force at this time is that the current collecting surfaces 1F ₁ and 2F ₂ are not deformed by the effect of the notch groove 10H, and therefore, compared with the case where the conventional substrate 1A in FIG. And the deformation rate is low,
The height dimension H of the first bridge portion 10B and the height of the current collecting surface F can be made uniform.

As a result, on the current collecting surface 1F, the contact pressure for contacting the cathode electrode and the anode electrode with the electrolyte plate becomes uniform, and the voltage drop due to the current concentration and the corrosion due to the temperature rise are suppressed, thereby suppressing the fuel cell. The life of the cell can be extended.

Further, by reducing the width wc of the intermediate portion C in FIG. 4, the area of the portion having the height representative value of 1 is relatively reduced, which further reduces the variation in the height of the entire current collecting surface. Can be made.

Further, as shown in FIG. 5, the cutout groove 10H has an R surface 11R formed at a corner portion of the first bridge portion 10B which is connected to the current collecting surface 1F. Therefore, the fuel cell is the first
When the pressing force applied to the bridge portion 10B changes and stress is repeatedly applied to the R surface 11, cracks are likely to occur in the left corner portion 11 ', but in the present invention, since the R surface 11 is used, the stress is dispersed. As compared with the corners, cracks are less likely to occur, and the life of the bridge type corrugated plate 1 can be extended.

FIGS. 6 to 7 are modifications of the bridge type corrugated sheet according to the present invention, in which the cutout directions of the bridges in the same row are orthogonal to each other, and the bridge positions of the first bridge row A and the second bridge row B are arranged. It shows a case where the second bridge portion 11B is moved so as to wrap it by a half width of the first bridge portion 10B. Also in this case, the cutout groove 10H of the first bridge portion 10B and the cutout groove 1H of the second bridge portion 11B which are adjacent to each other do not have the same direction, and only the half widths of the bridge portions do not overlap each other. The typical value of the height of the lattice is in the range of 0.5 to 1 as shown in FIG.
It can be seen that the flatness of the current collecting surface is improved as compared with the typical range 0 to 1 of the conventional bridge array shown in FIG.

Although the second bridge row B is displaced from the first bridge row A by the half width of the bridge in the figure, the moving width at this time is arbitrary.

Further, the cutout groove 10H of each bridge row is formed on the substrate 1A.
From the left side to the right side, a notch groove 10H perpendicular to the longitudinal direction of the substrate 1A and a notch groove 11H in the same direction as the longitudinal direction are formed. Therefore, when the oxidant gas 40 flows from the left side to the right side of the substrate 1A, that is, from the supply port to the outlet as shown by the chain line in FIG.
After passing 0H, the bridge portion 10B of the cutout groove 11H is bypassed and passes through the next first bridge portion 10B again.
There is an advantage that the cooling can be further improved by the eddy flow generated when bypassing.

Another embodiment of the present invention shown in FIGS. 9 and 10 will be described. 9 to 11, both the first bridge row A and the second bridge row B have the cutout grooves 10H of two adjacent first bridge portions 10B in the row in the same direction and parallel to each other. Further, the first bridge portion 10B in the second bridge row B corresponds to the current collecting surfaces 1F ₁ and 2F ₂ adjacent to the first bridge portion 10B of the first bridge row A so as not to overlap with the first bridge portion 10B. It is arranged in a zigzag.

In this case, as shown in FIG. 11, the typical value of the height of each lattice is 0.5 to 1 as indicated by the numbers in circles.
It can be seen that the flatness of the current collecting surface is improved as compared with the typical range 0 to 1 of the conventional bridge array shown in FIG. Also in this case, the flatness of the entire plane can be improved by reducing the width Wc of the intermediate portion with respect to the widths Wa and Wb of the bridge row.

Further, each first bridge portion 10B and each notch groove 1
Since 0H and 0H are dispersed and arranged on the substrate 1A, the mechanical strength of the substrate 1A is higher than that of the bridge portions of each row arranged in the same row as shown in FIG. You can be stronger.

Further, the notch grooves 10H in each row are arranged at right angles to the longitudinal direction of the substrate 1A from the left side to the right side of the substrate 1A. Therefore, when the gas flows from the left side to the right side of the substrate 1A, that is, from the supply port to the outlet, the gas flows without bypassing each bridge, so that the flow resistance becomes smaller than that in the structure in which the bridge portion is blocked,
The pump at the time of distribution needs only a small capacity, and power consumption can be saved.

12 and 13 show another modification of the bridge type corrugated plate according to the present invention. The first bridge row A is arranged in the same manner as that of FIG. 9, and a plurality of second bridge portions 11B formed by the notch grooves 10H formed in the direction perpendicular to the longitudinal direction of the substrate 1 are arranged. The second bridge row B is in the same direction as the cutout groove 10H and in the cutout groove 10H as in FIG.
And the cutout grooves 11H in the right-angled direction are alternately arranged, and the first bridge portion 10B and the cutout groove 10H in the first bridge row A are extended and the second bridge portion 11B and the cutout groove 11H in the second bridge row B are extended. Are arranged so that they do not overlap.

Also in this case, the typical value of the height of each grid is shown in FIG.
As shown in FIG. 1, the range is 0.5 to 1, and it is understood that the flatness of the current collecting surface is improved as compared with the typical range 0 to 1 of the conventional bridge array.

Further, in the cutout groove 10H of the first bridge row A and the cutout holes 10H and 11H of the second bridge row B, the pressure loss of gas similar to that in FIGS. 9 and 6 becomes small.

As another modification of the present invention, it is assumed that a grid-like division is made on a flat corrugated sheet material at the time of manufacturing a bridge type corrugated sheet.
When a bridge portion is formed in the lattice portion by forming a notch groove on two opposite sides of a predetermined lattice (a set of a plurality of lattices) in the lattice with a die or the like, the notch groove of the lattice is formed. It is also possible to make a notch with a depth that does not cut the plate on the other two sides. By cutting the other two sides, it is possible to reduce the amount of deformation of the flat portion adjacent to the lattice to be pushed during the pushing operation. Therefore, it is possible to improve the flatness of the current collecting surface of the corrugated plate after forming the convex portion.

Further, the case where the notch groove is formed on the flat plate in the mold will be described with reference to FIG. When a part of the first bridge row A and the second bridge row B surrounded by a chain line is a mold Z, the direction of the cutout groove 10H in the mold Z is right and left, and the cutout groove 1
In the direction of 1H, convexes are formed vertically. This notch groove 10
Corresponding to H and the notch groove 11H, the protrusions of the notch groove 11H and the notch groove 10H of the second bridge row B are formed in the mold Z. If this die Z is used, the notch grooves 10H and 1 having different directions can be formed by one type of die without exchanging the die one by one.
Since 1H can be formed at four places, the efficiency of the notch groove forming work can be significantly improved as compared with the case where the mold is replaced according to the notch grooves having different directions. This means that if each cutout groove arranged in the mold Z is regarded as one unit, one unit can be formed by one kind of mold. Further, since each notch groove 10H and notch groove 11H are arranged on a diagonal line, when the upper notch groove 10H is heavily worn, for example, if the lower notch groove 10H is rotated so as to be arranged at the upper side, Since the wear of each notch groove can be made uniform, the replacement of the mold Z can be reduced.

[0038]

As described above, according to the present invention, the height of the current collecting surface of the cell using the bridge type corrugated plate is equalized, and the contact state between the electrode and the current collecting surface is improved. Not only the performance of the cell is improved, but also the partial temperature rise due to the concentration of the current can be suppressed, so that the life of the cell can be extended.

[Brief description of drawings]

FIG. 1 is a side sectional view of a molten carbonate fuel cell shown as an embodiment of the present invention.

FIG. 2 is a plan view of the bridge type corrugated plate used in FIG.

3 is a sectional view taken along the line aa ′ of FIG.

FIG. 4 is an explanatory view showing a ratio of the flat surface of FIG.

5 is a partial plan view showing a part of FIG.

FIG. 6 is a plan view of a bridge type corrugated plate shown as an embodiment of the present invention.

7 is a sectional view taken along the line aa ′ of FIG.

FIG. 8 is an explanatory view showing a ratio of the flat surface of FIG.

FIG. 9 is a plan view of a bridge type corrugated plate shown as an embodiment of the present invention.

10 is a sectional view taken along the line aa ′ of FIG.

11 is an explanatory diagram showing a ratio of the flat surface of FIG. 9. FIG.

FIG. 12 is a plan view of a bridge type corrugated plate shown as an embodiment of the present invention.

13 is a sectional view taken along the line aa ′ of FIG.

14 is an explanatory diagram showing a ratio of the flat surface of FIG.

FIG. 15 is a plan view of a bridge type corrugated plate used in a conventional molten carbonate fuel cell.

FIG. 16 is a perspective view of a conventional bridge type corrugated plate.

17 is a sectional view taken along the line aa ′ of FIG.

FIG. 18 is a partial plan view showing a part of FIG.

FIG. 19 is an explanatory diagram showing a ratio of the flat surface of FIG. 12.

[Explanation of symbols]

1 ... Bridge type corrugated plate, 1A ... Substrate, 1F, 1F ₁ , 2F ₂
... Current collecting surface, 1H ... Notched groove, 10 ... Cell configuration, 10B ... First bridge part, 11B ... Second bridge part, 10H, 11
H ... Notch groove, 11A ... Anode electrode, 11C ... Cathode electrode, 12 ... Electrolyte plate, 13 ... Partition plate, 14 ... Gas passage.

Continuation of front page (56) Reference JP-A-9-82344 (JP, A) JP-A-7-254424 (JP, A) JP-A-10-92447 (JP, A) JP-A-2-160371 (JP , A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01M 8/00-8/24

Claims (5)

(57) [Claims] 1. A carbonate is reacted with the cathode electrode to generate carbon ions from the oxygen-containing gas consisting mainly of air and carbon dioxide, and an electrolyte plate for passing the carbonate ion, the hydrogen carbonate ions and fuel gas a cell structure comprising an anode electrode for generating a gas and water vapor, as well as housing the cell structure, and a partition plate for separating the oxidant gas and the fuel gas, which is formed between the partition plate and the cell structure In a fuel cell separator composed of a bridge type corrugated plate that presses and supports a cell structure arranged in a gas passage, a substrate between a notched groove and a notched groove facing each other to the substrate of the bridge type corrugated plate is on the partition plate side. Equipped with a protruding bridge part,
During the bridge sequence in which a plurality of the bridge portions in a row
The fuel cell separator through a septum disposed in a plurality of rows, characterized in that a first bridge portion adjacent notched groove of the second bridge portion is so configured not opposed in the same direction. 2. A part of the second bridge portion of the second bridge row is arranged so as to wrap between the first bridge portion of the first bridge row and the first bridge portion. 1. The fuel cell separator according to 1. A cathode electrode from wherein oxidant gas mainly composed of air and carbon dioxide gas to generate carbon ions, and an electrolyte plate for passing the carbonate ion, carbonate by reacting the hydrogen carbonate ions and fuel gas a cell structure comprising an anode electrode for generating a gas and water vapor, as well as housing the cell structure, and a partition plate for separating the oxidant gas and the fuel gas, which is formed between the partition plate and the cell structure In a fuel cell separator composed of a bridge type corrugated plate that presses and supports a cell structure arranged in a gas passage, a substrate between a notched groove and a notched groove facing each other to the substrate of the bridge type corrugated plate is on the partition plate side. Equipped with a protruding bridge part,
During the bridge sequence in which a plurality of the bridge portions in a row
The bridge rows are arranged in a plurality of rows with a gap between them, and the notch grooves of the adjacent first bridge section and second bridge section of each bridge row are configured so as not to face each other in the same direction.
And a cutout groove of the second bridge portion is arranged in a direction perpendicular to the longitudinal direction of the substrate and in the same direction as the longitudinal direction. 4. The fuel cell separator according to any one of claims 1 to 3, wherein the fuel cell separator is configured to form an R surface at an end of the cutout groove. A cathode electrode from wherein oxidant gas mainly composed of air and carbon dioxide gas to generate carbon ions, and an electrolyte plate for passing the carbonate ion, carbonate by reacting the hydrogen carbonate ions and fuel gas a cell structure comprising an anode electrode for generating a gas and water vapor, as well as housing the cell structure, and a partition plate for separating the oxidant gas and the fuel gas, which is formed between the partition plate and the cell structure In a fuel cell separator composed of a bridge type corrugated plate that presses and supports a cell structure arranged in a gas passage, a substrate between a notched groove and a notched groove facing each other to the substrate of the bridge type corrugated plate is on the partition plate side. Equipped with a protruding bridge part,
During the bridge sequence in which a plurality of the bridge portions in a row
A mold formed in a plurality of rows with a space between the mold, the mold comprising a first convex portion having a pair of first notch grooves formed in a direction perpendicular to the longitudinal direction of the substrate, and the first convex portion. A second row having a pair of second notch grooves formed in the same row in the same direction as the longitudinal direction of the substrate.
A first bridge sequence consisting of a protrusion, said first protrusion is disposed so as to correspond, and a second convex portion having a longitudinal direction and a pair of second cutout groove formed in the same direction of the substrate, The second
It is arranged in the same row as the convex portion so as to correspond to the second convex portion of the first bridge row , and is formed in the direction perpendicular to the longitudinal direction of the substrate.
Second comprising a first projecting portion having a pair of first cutout groove which is
A mold for forming a bridge type corrugated sheet used in a fuel cell separator, characterized in that a unit consisting of a bridge row and the bridge row is constituted.