JPS61133579A - Exchanging fuel cell blocks - Google Patents

Abstract

PURPOSE:To enable exchanging a fuel cell block having defective cells for a new block smoothly and without damaging other cells by exchanging them with the surfaces of the blocks being pressed. CONSTITUTION:Clamping studs 13 are loosened to lower the pressure on the surfaces of cells. A new block 1b to be used as a new one is inserted in a protecting frame 5 employed as a framework. An L-shaped pushing pedestal 9 provided with side plates and a reception pedestal 10 are installed, sandwiching the stack to be exchanged from both sides under its lower surface downward. On the upper side of the block to be exchanged a clamping plate 8, 8a are butted to the side surface of the stack through cushion material 20, and are fixed on the block using an arm 11. An oil pressure jack 18 is installed on the pushing pedestal 9, and a new block 1b to be inserted is placed on the space between the jack and the block 1a to be exchanged. Using the oil pressure jack 18 the block 1a is pushed on the reception pedestal 10, and the block 1b is placed, together with the protection frame 5, on the position where the exchanged block was placed. Thereafter the clamping plate, the pushing pedestal, the reception pedestal, together with the protection frame 5, are demounted and the pressure acting on the surfaces of the cells is adjusted.

Description

Detailed Description of the Invention [Technical Field to which the Invention Pertains] The present invention relates to a stack of blocks each formed by stacking a plurality of square cell cells and tightening them with a predetermined pressure. The present invention relates to a method for replacing blocks of fuel cells in an assembled state.

[Prior art and its problems]

In general, a fuel cell consists of a matrix layer that holds an electrolyte, a porous fuel electrode and an oxidizer electrode that sandwich this layer, and a plate with grooves formed on the outside that supplies fuel gas as a reaction gas. , a unit cell consisting of a plate with a groove for supplying oxidizing gas in a direction perpendicular to the supply groove, and a cooling plate interposed between each of the unit cells to cool the heat generated during fuel cell operation. A cell stack of a fuel cell is constructed by stacking a large number of columns in a columnar manner, and tightening them in the stacking direction with a predetermined pressure using a tightening means.

Furthermore, in Utility Application No. 59-1519, the present applicant previously disclosed that a plurality of cells were stacked between cooling plates to form a block, and a unit in which a plurality of blocks and cooling plates were stacked was pressed against the surface by tightening means. We are proposing a configuration that can be replaced with the addition of . By testing the characteristics of this unit before stacking it in a cell stack, only units with good characteristics can be assembled into the cell stack, and units with defective cells can be assembled into the cell stack. It can be avoided.

However, in recent years, the number of stacked units has tended to increase, and in a unit consisting of 80 cells, the entire unit becomes unusable due to a defect in just one cell. In addition, in a cell stack consisting of several hundred cells regardless of the unit structure, if one cell is defective, all the several hundred cells must be replaced.

The reason for this is that when a defective cell is removed and a new good cell is inserted into the unit or cell stack, the tightening surface pressure of the unit or cell stack must be released. As a result, the matrix, sealing material, etc. of the cell are damaged, resulting in deterioration in battery characteristics, burnout, and leakage of reaction gas even after replacing a good product.

[Purpose of the invention]

In view of the above-mentioned points, the present invention provides a fuel cell block replacement method that allows a block containing a defective σ to be replaced without damaging the unit or other cells in the cell stack and the cooling plate. The purpose is to provide.

[Summary of the invention]

According to the present invention, a block is constructed in which a plurality of rectangular cells are stacked in advance, and the blocks are interposed between cooling plates, stacked, and tightened in the stacking direction with a predetermined pressure. A fuel cell block exchanging method of exchanging the block from a unit or cell stack as a constituent stack, the method comprising: exchanging the block from opposite sides of the unit so that the block to be exchanged can slide in a direction perpendicular to the stacking direction; The first one is L-shaped and has a side plate.
and a second base plate, which is connected to the side plate by tightening the block through a joint plate, while straddling the cooling plate adjacent to the upper part of the block and extending upwardly from the opposite side plate of the stack. Presser plates are brought into contact with both side surfaces in the same direction as the side surfaces, and the presser plates are tightened and connected via a connecting plate so as to interpose the block, and at least one of the presser plates is attached to the slide of the block. Connecting to the peripheral edge of the first base plate along the direction via an arm, and attaching a pushing means to the first base plate, assembling a replacement block consisting of the same size and the same number of single cells as the block to be replaced. 9. The framework housed in the removable framework flush with the height of the frame is placed between the extrusion means and the block to be replaced.
After reducing the predetermined pressure to a pressure that can maintain the allowable surface pressure of the unit cell, the extrusion means slides the framework, and the block to be replaced is slid onto the second base plate. This is accomplished by removing the framework, first and second base plates, presser plates, and arms, and tightening the stack with a predetermined pressure.

[Embodiments of the invention]

The present invention will be described in detail below based on the drawings.

FIG. 1 is a sectional view showing a state in which a block having a cell determined to be a defective cell is being replaced as a result of a test in a unit as a stack according to an embodiment of the present invention. 1st
In the figure, a block 1 is composed of a plurality of cells and is interposed between cooling plates 2 on which cooling pipes 2a are arranged.

Note that the seal between the block 1 and the cooling plate 2 is performed using a sealing material such as a non-adhesive Teflon tape. A plurality of these are stacked, and an upper end plate 3 is disposed on the upper end surface, and a lower end plate 4 is disposed on the lower end surface to form a unit. An upper temporary end plate 3a is disposed above the upper end plate 3, a lower temporary end plate 4a is disposed below the lower end plate 4, and an upper clamping plate 6 and a lower clamping plate 7 are disposed on the outside thereof. are provided respectively, and the unit is tightened via a disc spring 14 by a tightening stud 13 passing through these tightening plates.

Note that the upper and lower temporary end plates 3a14a are shown in FIG.
As shown in FIG. 2, which is a partial cross-sectional view, grooves (9) and 31 and grooves 30a and 31 extend between the upper end plate 3 and the upper temporary end plate 3, and between the lower end plate 4 and the lower temporary end plate 4a, respectively.
A is provided. A retaining member for tightening this unit is inserted into the grooves 30, 30a, and a retaining member for tightening the unit adjacent to this unit is inserted into the grooves 31, 31a.

Therefore, in the test of the unit described above, the groove 3 of the end plate 3°4
The test is conducted by inserting an engaging member into the cells 0 and 30a and tightening them with a tightening bolt through the retaining member so that surface pressure during operation is applied to the cell. If a defective cell is found as a result of the test, the grooves 30, 30 of the temporary end plates 3a, 4a
By inserting the engaging members inserted into the grooves of the end plates 3 and 4 into the grooves of the end plates 3 and 4, the clamping plates 6 and 7 are fitted onto the flat end surfaces of the temporary end plates 3a and 4a, respectively, as shown in FIG. It will be posted. After tightening with the tightening stud 13 so that surface pressure during operation is applied to the cell, the above-mentioned retaining member is removed. Therefore, a predetermined surface pressure is always maintained in the cells of the unit.

Next, the method of replacing the lock will be explained with reference to FIG. First, in order to make replacement easier, reduce the frictional force during replacement, and protect the new block to be replaced, the tightening stud 13 is loosened, and the spring force of the disk spring 14 is weakened, making it easier to use during operation or testing. Surface pressure applied to the cell 3KP/1m
Lower t to about 0.5~/d.

If the surface pressure is about 0.5 KP/in', the cell's Maru-IJ
No wax damage occurs.

Next, a block to be replaced, which has the same size and the same number of cells as the block to be replaced, is inserted into a protective frame 5 as a framework, as shown in FIG. The protective frame 5 has the same height as the block, and has frame plates 5a and 5b made of a rigid material 1, such as iron.
are assembled and tightened with embedded bolts n to allow for assembly and disassembly.

The embedded pole 22 is provided so as to pass through a frame plate, for example, a frame plate 5a, which faces perpendicularly to the block moving direction, which will be described later. The block 16 to be replaced is held in the protective frame 5 by placing a rubber-like binding material around the block 16 and tightening it with the frame plates 5a and 5b.

Next, from the lower end surface of the 70 pieces to be replaced, the stack is sandwiched in the downward direction, and the pusher base 9 as the first base plate and the support base as the second base plate are provided with side plates in an L-shape on both sides. 10
and. The push stand 9 and the receiver are 9a, 1 on the side plate of the stand 10.
0a is a side plate 9a which is brought into contact with the side surface of the cell stack through a cushioning material such as rubber, as shown in the AA cross section of FIG. 1 shown in FIG.

10a is connected via a joint plate 17 so as to interpose the stack, and is tightened with bolts. In addition, by inserting spacers between the pusher 9 and the receiver 10, the clamping plate 7 and the side plates 9a and 10a, the blocks of the pusher 9 and the receiver 10 can be replaced. Adjust the height of the space so that it is flush with the bottom end of the block.

In addition, presser plates 8 and 8a are placed on opposite sides of the stack in the upward direction, straddling the cooling plate adjacent to the top of the block to be replaced. B in FIG. 1 shown in FIG.
As shown in the -B cross section, the holding plates 8 and 8a are connected via the joint plate 17 so as to interpose the stack, and are tightened by tightening the bolts. Further, at least one of the presser plates 8 is attached and fixed via an arm 11 to the side surface as the peripheral edge of the side plate 9b of the presser stand 9, as shown in FIG. Therefore, the blocks interposed between the presser plates 8 and 8a are also fixed.

Next, a hydraulic jack 18 as a pushing means whose position is adjusted by a spacer 19 is provided on the pusher 9, and a block 1b to be replaced is placed on the pusher 9 between the hydraulic jack 18 and the block 1a to be replaced. I'll put it on. At this time, the protective frame 5 is attached to the side plate 17a of the joint plate 17 as shown in FIG.
and is placed within the guide plate 21 connected to this side plate 17a.

Next, when the block 1b is pressed against the block 1a by the hydraulic jack 18, the block 1b is guided by the guide plate 21 and the side plate 17a of the joint plate 17 and slides, and as shown in FIG. extruded on top of 10,
On the other hand, the block 1b to be replaced is placed together with the protection frame 5 at the position of the block to be replaced. In this case, the surface of the block 10 is flush with the lower surface of the block 1a, so the block 1 is smoothly pushed onto the block 10 without receiving any unreasonable force other than the horizontal extrusion force. Glide across the surface. Note that when extruding the block 1b, it is desirable to place a weight n on top of the block 1b to prevent the cells from floating up.

As described above, the block 1b is placed at the position of the stack to be replaced with the rear presser plate 8 and the 8at arm 11° presser stand 9.
．． For the receiver, remove the base 10 and the joint plate 17, and then remove the protective frame 5.
Remove the frame plates 5a and 5b (see Fig. 3) to make it a regular unit.

Next, the disc spring 14 of the tightening stud 13 is tightened with the nut 16, and the replacement is completed by making the surface pressure on the cell equal to the surface pressure during operation or testing.

Note that block exchange for cell stacks instead of units can be performed in the same manner.

〔Effect of the invention〕

As is clear from the above explanation, according to the present invention, blocks are replaced while applying surface pressure, so that blocks with defective cells can be replaced smoothly and new blocks can be replaced without damaging other cells. It has the effect of being able to be exchanged with Therefore, the unit or cell stack in which a defective cell has occurred will not become completely unusable, and the
Since only a block of 10 cells is made unusable, the yield is improved and the cost and manufacturing period are reduced.

[Brief explanation of drawings]

FIG. 1 is a vertical cross-sectional view showing a block exchange state of a fuel cell according to an embodiment of the present invention, FIG. 2 is a partial cross-sectional view taken along line CC in FIG. 1, and FIG. 3 is a plan view of the framework in FIG. 1. Figure 4 is a sectional view taken along A-A and B-B in Figure 1, and Figure 5 is a cross-sectional view of Figure 1.
It is a longitudinal cross-sectional view which shows the state in which the block in the figure was replaced. 1 Ni block, 2: Cooling plate, 5: Frame, 8, 8a: Holding plate, 9: First base plate, 10: Second base plate, 9a, 10
a: side plate, 17: joint plate,] 8: extrusion means.

Claims (1)

[Claims] A block is formed by stacking a plurality of rectangular cells in advance, and the blocks are interposed between cooling plates and stacked in plurality,
A fuel cell block replacement method in which the block is replaced from a stack configured by tightening in the stacking direction with a predetermined pressure, the block being replaced facing the stack so that it can slide in a direction perpendicular to the stacking direction. first and second base plates each having an L-shape and having side plates on both sides thereof are provided, and the side plates are brought into contact with the sides of the stack, respectively;
The side plates of the first and second base plates are tightened and connected via a joint plate so as to interpose the block, while straddling the cooling plate adjacent to the top of the block and extending upwardly toward the opposite side of the stack. A presser plate is brought into contact with both side surfaces in the same direction as the side surface, and the presser plate is tightened and connected to the block via a joint plate, and further, at least one of the presser plates and the first The base plate is connected to the peripheral edge of the block along the sliding direction through an arm, and a pushing means is attached to the first base plate, and the block is replaced with cells of the same size and number as the block to be replaced. The blocks are housed in a frame that can be assembled and disassembled flush with the height of the frame, and the framework is placed on a first base plate between the extrusion means and the block to be replaced, and the predetermined pressure is applied to the unit cell. After reducing the permissible surface pressure of 1. A fuel cell block replacement method characterized in that the block is replaced by removing the base plate, presser plate, and arm No. 2 and tightening them to the stack with a predetermined pressure.