JP2002358993A - Laminated fuel cell and measuring method of cell voltage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a laminated fuel cell in which fitting of a voltage terminal to the separator is easy, and electrical contact between the voltage terminal and the separator is steady, and the number of troublesome voltage measuring cables can be reduced, and a measuring method of the cell voltage. SOLUTION: A voltage terminal 25, in which a metallic plate having elasticity is made in U-shape by connecting a pair of side portions 25b, 25c to the main portion 25a, is attached clipped at one part of the separator 21 so that the main portion and side portions may be contacted on the side face and both faces of the front and rear of the separator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a stacked fuel cell such as a polymer electrolyte fuel cell and a phosphoric acid fuel cell, and more particularly to a structure of a voltage terminal and a method of measuring a cell voltage.

[0002]

2. Description of the Related Art In conventional stacked fuel cells such as solid polymer fuel cells and phosphoric acid fuel cells, carbon separators are used. Then, in order to measure the voltage of the cells constituting the stacked fuel cell, holes are formed in every cell or every other cell, and the tip of the voltage measurement line is inserted into the hole and carbon paste or adhesive is used. Generally, a method of bonding and fixing is adopted.

FIGS. 27 and 28 are perspective views of a separator applied to a conventional stacked fuel cell as viewed from a first main surface side and a second main surface side, respectively. 27 and 28, a separator 1 is made of carbon, and has opposite first and second main surfaces 1a and 1b each having a rectangular surface.
It is formed in a flat plate shape. Then, peripheral gas seal portions 2a, 2b are formed on the outer peripheral portions of the first and second main surfaces 1a, 1b of the separator 1, respectively, and the first and second separators 1 of the separator 1 surrounded by the peripheral gas seal portions 2a, 2b. The parts of the main surfaces 1a and 1b form the reaction parts 3a and 3b. Further, the oxidizing gas inlet manifold 4, the oxidizing gas outlet manifold 5, the fuel gas inlet manifold 6, the fuel gas outlet manifold 7, the cooling water inlet manifold 8, and the cooling water outlet manifold 9 are connected to the peripheral gas seal portions 2a, 2b by the separators 1. Has been drilled. Further, the bolt insertion hole 13 of the tightening bolt is provided with the separator 1.
The four corners are drilled.

An oxidizing gas passage groove 11 is formed in the reaction portion 3a of the first main surface 1a so as to communicate the oxidizing gas inlet manifold 4 and the oxidizing gas outlet manifold 5, and a fuel gas passage groove 12 is formed. The fuel gas inlet manifold 6 and the fuel gas outlet manifold 7 are formed in the reaction portion 3b of the second main surface 1b so as to communicate with each other. Although not shown, the cooling water flow passage groove is formed in the cooling water gas inlet manifold 8.
The cooling water gas outlet manifold 9 is formed inside the separator 1 so as to communicate therewith. Note that the cooling water passage need not be formed in all the separators 1 and may be formed in the separators 1 for each predetermined number of cells. Further, the hole 10 for attaching the voltage measurement line is formed on the side surface 1 of the separator 1.
c.

[0005] As shown in Fig. 29, a conventional stacked fuel cell is a single cell in which a separator 1 thus manufactured is integrated with a fuel electrode and an oxidant electrode by sandwiching an electrolyte membrane therebetween. A predetermined number of the electrode / membrane assemblies 15 are alternately stacked to form a laminate. Then, end plates 16 are disposed at both ends of the laminate in the laminating direction, and a tightening bolt (not shown) is attached to each bolt. The end plate 16 and the laminated body are tightly integrated with each other by using the fastening bolts. In the stacked fuel cell thus manufactured, the oxidizing gas inlet manifold 4, the oxidizing gas outlet manifold 5, the fuel gas inlet manifold 6, the fuel gas outlet manifold 7, the cooling water inlet manifold 8, and the cooling water outlet manifold 9 Are independent of each other in the laminating direction, the oxidizing gas flow channel groove 11 faces the oxidizing electrode of the electrode / membrane assembly 15, and the fuel gas flow channel groove 12 faces the fuel electrode of the electrode / membrane assembly 15. Is relative to. In addition, current collecting electrodes 17 and 18 are provided at both ends in the stacking direction of the stacked body.

[0006] The voltage measurement line 19 is connected to each separator 1.
Attached to. The tip of the voltage measurement line 19 is inserted into the hole 10, and a carbon paste or a resin-based adhesive obtained by mixing carbon powder and an adhesive is poured into the hole 10 and the root of the tip of the voltage measurement line 19. The adhesive 14
Is dried and fixed to the separator 1.

In the fuel cell having the above-described structure, the oxidizing gas flows from the oxidizing gas inlet manifold 4 to the oxidizing gas flow path 11 and is supplied to the oxidizing electrode of the electrode / membrane assembly 15. Then, the fuel gas flows from the fuel gas manifold 6 to the fuel gas flow channel 12 and the electrode / membrane assembly 15
Is supplied to the fuel electrode. Then, the oxidizing gas and the fuel gas are discharged from the oxidizing gas outlet manifold 5 and the fuel gas outlet manifold 7, respectively. Thereby, the electrochemical reaction proceeds at the oxidant electrode and the fuel electrode, and generates electric power. Then, the DC power is applied to the collecting electrodes 17 and 18.
Taken out of At the same time, the cooling water flows from the cooling water inlet manifold 8 into the cooling water flow channel, and is discharged from the cooling water outlet manifold 9. Thereby, the temperature rise of the fuel cell is suppressed. Further, in order to detect an abnormality of the cell, the voltage of each cell is monitored using a voltage measurement line 19 attached to each separator 1.

In the conventional stacked fuel cell, since the voltage measurement line 19 is attached as described above, the metal wire at the tip of the voltage measurement line 19 and the carbon of the separator 1 always have sufficient contact. Adhesive 14 that cannot be applied to the bottom of the voltage measurement line 19
However, this causes an increase in electric resistance between the metal wire of the voltage measurement line 19 and the separator 1, and there is a problem that correct voltage measurement is essentially difficult. Further, when a separator having a thickness of less than 3 mm is used in order to reduce the size of the stacked fuel cell, it has become extremely difficult to provide a hole for attaching a voltage measurement line on the side surface of the separator. In addition, carbon separators have been molded to reduce costs, but it is difficult to mold holes on the side of the separator with mold-type separators manufactured using metal molds. Holes had to be made by post-processing, leading to increased costs. Also, making holes in the side surfaces of the thin separator leads to weakening of the mechanical strength of the separator, which may lead to troubles such as cracking of the separator due to temperature history during operation of the stacked fuel cell.

When the thickness of the separator 1 is reduced, it is necessary to disperse the mechanical force applied to the hole 10 for attaching the voltage measurement line. Therefore, as shown in FIG. 29, the separators 1 are arranged so that the positions of the holes 10 are alternately arranged to disperse mechanical stress, thereby suppressing occurrence of a damage accident of the separator 1. This also has the effect of preventing short-circuiting due to contact between the tips of the adjacent voltage measurement lines 19.

However, as the number of stacked layers increases, the number of voltage measuring lines 19 also increases, so that wiring to the voltage measuring terminal becomes complicated, and a large number of voltage measuring lines 19 taken out of the stacked fuel cell are stacked. It also caused the compact fuel cell to lose its compactness. In particular, in a stacked fuel cell used as a power source of a fuel cell vehicle or a portable power source, the voltage measurement line 19 may be mixed in the middle due to frequent vibrations and the like, and the cell may be short-circuited. The measurement line 19 is pulled and a part of the connection between the voltage measurement line 19 and the separator 1 is disconnected, which may lead to malfunction such as detection of abnormal cell voltage. Further, a voltage measuring terminal for connecting many voltage measuring lines 19 and measuring means for measuring the respective voltages are required, and the cell voltage has to be measured using an expensive data logger or the like.

The cell voltage is, for example, every 10 cells or 20
If the measurement is performed at every other cell or at a large interval, the number of voltages to be measured is reduced, and the number of voltage measurement lines 19 is also reduced. However, a stacked fuel cell is a series device, and if an abnormality such as fuel shortage occurs even in one of the stacked cells, power generation cannot be performed and fatal damage may occur. Therefore, in order to detect an abnormality of a cell in advance, it is required to measure a voltage for each of a small number of cells, preferably for each cell.

[0012]

Since the conventional stacked fuel cell is configured as described above, the voltage measurement line 19 is not required.
There was a trouble such as the separator 1 cracking due to the provision of the hole 10 for mounting the. In addition, there are problems that the number of the voltage measurement lines 19 increases and the voltage measurement lines 19 become complicated, and a large number of voltage measurement terminals are required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and makes it easy to attach a voltage terminal to a separator, secures electrical contact between the voltage terminal and the separator, and reduces the complexity. It is an object of the present invention to provide a stacked fuel cell capable of reducing the number of voltage measuring cables and a method for measuring the cell voltage thereof.

[0014]

A stacked fuel cell according to the present invention is constituted by alternately stacking a unit cell integrally joined by sandwiching an electrolyte membrane between a fuel electrode and an oxidant electrode, and a separator. A stacked fuel cell including the stacked body,
A U-shaped voltage terminal formed by connecting a pair of side portions of a metal plate having a spring property by a main portion is provided on a part of the side surface of the separator. Are sandwiched so as to be in contact with the side surface and the front and back surfaces, respectively.

[0015] Further, a recess for accommodating a pair of side portions of the voltage terminal is recessed on both front and back surfaces of the separator.

Further, the separator comprises a first separator having a fuel gas passage groove formed on a main surface thereof, and a second separator having an oxidizing gas passage groove formed on a main surface thereof, which is opposite to the main surface. The voltage terminals are connected to the first side by the first side.
And the second separator is held so as to be in contact with the main surface of the second separator.

Further, the separator comprises a first separator having a fuel gas flow channel formed on a main surface thereof and a second separator having an oxidizing gas flow channel formed on a main surface thereof, which is opposed to the main surface on the opposite side. The voltage terminals are connected to the pair of side portions by the first side.
And the second separator is sandwiched so as to be in contact with a main surface and an opposing surface of one of the separators, and a concave portion for accommodating one of the pair of side portions is provided on the main surface of the one of the separators. A recessed portion for receiving the other side portion is provided on the surface of the first and second separators facing the other separator.

The voltage terminal is sandwiched between the separators every several cells.

The voltage terminals are sandwiched between two opposite sides of the separator and substantially diagonally.

Further, an electrical insulating coating is provided on a side surface of the laminate so as to expose at least a part of a main portion of the voltage terminal.

Further, the above-mentioned electric insulating coating is formed by applying silicone rubber.

Further, the electric insulating coating is such that a liquid or paste-like silicone rubber is applied to a side surface of the laminate so that at least a part of a main portion of the voltage terminal is exposed, and a pressure inside the laminate is reduced. After the pressure is reduced, the silicone rubber is dried and solidified, and then the interior of the laminate is returned to normal pressure to form the silicone rubber.

[0023] Further, a mounting portion for the voltage measuring wire is formed in the main portion of the voltage terminal, and the voltage measuring wire is soldered to the mounting portion.

Further, the method of measuring the cell voltage of a stacked fuel cell according to the present invention is characterized in that a fuel cell and an oxidant electrode sandwich an electrolyte membrane and are joined and integrated, and a separator is alternately stacked. In the method for measuring a cell voltage of a stacked fuel cell having a stacked body constituted by the above, a metal plate having a U-shaped spring property formed by connecting a pair of side portions by a main portion is formed on a side surface of the separator. Of the separator, the main part and the side part thereof are sandwiched so as to be in contact with the side surface and the front and back surfaces of the separator, respectively, to form a voltage terminal, and a voltage measurement line is brought into electrical contact with the voltage terminal. It measures the voltage of each cell or every several cells.

Also, a pair of movable probes are mounted on the side surface of the laminated body so as to be movable in the laminating direction of the laminated body, and the pair of movable probes are respectively moved to be connected to the two voltage terminals arbitrarily selected. The cells are brought into contact with each other to measure the cell voltage.

Further, a pair of fixed probes are fixed to both ends of the laminate, respectively, and one movable probe is
The movable body is attached to a side surface of the laminate so as to be movable in the laminating direction of the laminate, and the movable probe is moved so as to be in contact with the arbitrarily selected voltage terminal. It measures voltage.

Also, a pair of movable probes set at an interval between the adjacent voltage terminals are movably mounted on the side surface of the laminate in the direction of lamination of the laminate, and the pair of movable probes are moved. The adjacent voltage terminals are brought into contact with each other to measure the cell voltage of an arbitrary single cell.

Also, a pair of movable probes set at intervals of a plurality of times of the interval between the adjacent voltage terminals are movably attached to the side surfaces of the laminate in the direction of lamination of the laminate, and The probe is moved and brought into contact with the voltage terminals having a plurality of intervals, respectively, to measure a cell voltage between any number of cells.

Also, a probe group consisting of at least three movable probes arranged at intervals of a predetermined number of times the interval between the adjacent voltage terminals can be moved to the side surface of the laminate in the laminating direction of the laminate. Attach and move the probe group to bring each of the movable probes into contact with the voltage terminal, and measure at least two cell voltages.

Further, the voltage terminals are sandwiched between two opposite sides of the separator and substantially at diagonal positions, and a movable probe is attached to two opposite side surfaces of the laminate in the laminating direction of the laminate. The probe is movably attached, the movable probe is moved to contact the voltage terminals on two opposite sides of the laminate, and the cell voltage of each single cell or every several cells is measured at two points.

[0031] Further, a projection is protruded from a main portion of the voltage terminal so that contact between the voltage terminal and the movable probe is made only by the projection.

The movable probe is brought into contact with the arbitrarily selected voltage terminal at regular time intervals or according to a command from a control device to measure the voltage of a single cell or several cells. is there.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 FIG. FIG. 1 is a side view showing a stacked fuel cell according to Embodiment 1 of the present invention, and FIGS. 2 and 3 respectively show a first main assembly of a separator applied to the stacked fuel cell according to Embodiment 1 of the present invention. FIG. 4 is a perspective view showing a state seen from the surface side and the second main surface side, and FIG. 4 is a first embodiment of the present invention.
FIG. 5 is a perspective view showing a state in which voltage terminals of a separator applied to the stacked fuel cell according to Embodiment 1 are mounted, and FIG. 5 is a cross-sectional view showing a main part of the stacked fuel cell according to Embodiment 1 of the present invention. In each of the drawings, the same or corresponding parts as those in the conventional apparatus shown in FIGS. 27 to 29 are denoted by the same reference numerals, and description thereof will be omitted.

In FIG. 1, a stacked fuel cell 100 is
A laminate 20 comprising a predetermined number of alternately laminated electrode / membrane assemblies 15 and separators 21 as single cells;
End plates 16 respectively disposed at both ends in the stacking direction of the above, and current collecting electrodes 17 interposed between the stacked body 20 and the end plates 16,
18. The stacked body 20, the current collecting electrodes 17, 18 and the end plate 16 are integrally fastened by a fastening bolt (not shown). The stacked fuel cell 100 shown in FIG. 29 is different from the conventional stacked fuel cell shown in FIG. 29 except that a separator 21 is used instead of the separator 1 and a voltage terminal 25 is sandwiched between the separators 21. It is configured similarly to a battery.

Here, the separator 21 and the voltage terminal 2
5 will be described with reference to FIGS. The separator 21 is made of carbon, and is formed in a flat plate shape having opposite first and second main surfaces 21a and 21b. Then, peripheral gas seal portions 22a and 22b are formed on the outer peripheral portions of the first and second main surfaces 21a and 21b of the separator 21, respectively, and the first and second portions of the separator 21 surrounded by the peripheral gas seal portions 22a and 22b are formed. The parts of the main surfaces 21a and 21b are the reaction part 2
3a and 23b are formed. The engaging recess 24 is formed to extend from the peripheral gas seal portion 22a of the first main surface 21a of the separator 21 to the peripheral gas seal portion 22b of the second main surface 21b via the side surface 21c. The engagement recess 24 is formed with a recess 24 a having a depth of 0.3 mm formed in the peripheral gas seal portion 22 a and a peripheral gas seal portion 2 a.
It is composed of a recess 24b with a depth of 0.3 mm recessed at 2b and a recess 24c with a depth of 0.3 mm recessed at the side surface 21c. The voltage terminal 25 is formed by bending a tin-plated iron plate having a thickness of 0.3 mm and a length of 20 mm and having a spring property and connecting a pair of side portions 25b and 25c with a main portion 25a to form a U-shape. ing. The pair of side portions 25b and 25c are formed such that the distance between the roots is equal to the thickness of the engaging concave portion 24 (the thickness between the concave portions 24a and 24b), and the distance between the distal ends is reduced.

The oxidizing gas inlet manifold 4, the oxidizing gas outlet manifold 5, the fuel gas inlet manifold 6, the fuel gas outlet manifold 7, the cooling water inlet manifold 8, and the cooling water outlet manifold 9 are provided with peripheral gas seal portions 22a, 22b. Are provided through the separator 21. Bolt insertion holes 13 for fastening bolts are formed at four corners of the separator 21. The first main surface 21a is arranged such that the fuel gas passage groove 11 communicates with the fuel gas inlet manifold 6 and the fuel gas outlet manifold 7.
Of the second main surface 21b such that the oxidizing gas passage groove 12 communicates with the oxidizing gas inlet manifold 4 and the oxidizing gas outlet manifold 5.
3b.

The voltage terminal 25 is connected to a pair of side portions 25.
B and 25c are inserted into the engagement recess 24 while pushing and spreading the tip side. Therefore, as shown in FIGS. 4 and 5, the voltage terminal 25 has the pair of side portions 25b and 25c in surface contact with the bottom surfaces of the recesses 24a and 24b, and the main portion 25a has surface contact with the bottom surface of the recess 24c. Then, it is sandwiched between the separators 21. At this time, the spring force of the pair of side portions 25b and 25c prevents the voltage terminal 25 from coming off the separator 21 and maintains the surface contact between the voltage terminal 25 and the separator 21. Further, the pair of side portions 25b, 25c and the first and second main surfaces 21a, 21b are in the same plane position, and the main portion 25a and the side surface 21c are in the same plane position.

Therefore, according to the first embodiment, since the voltage terminal 25 is attached to the engaging recess 24 of the separator 21 in a good surface contact state due to its spring property, the contact resistance is kept small and the electrical connection is maintained. Connections are made. Also,
Since the voltage terminal 25 is made of a U-shaped metal piece having a spring property, the voltage terminal 25 has a pair of side portions 25b, 2
The voltage terminal 5c is attached to the engaging recess 24 while being spread, so that the voltage terminal 25 can be easily attached to the separator 21. Further, a pair of side portions 25b, 25c of the voltage terminal 25 are provided.
Are the first and second major surfaces 22a, 22 of the separator 21
Since it is located on the same plane as b, even if the voltage terminal 25 is attached, the electrode / membrane assembly 15 will not be damaged.
Further, since the engaging recess 24 is formed in the separator 21, the plate thickness of the voltage terminal 25 can be increased accordingly.
The spring property of the voltage terminal 25 can be strengthened. Thereby, the contact resistance between the voltage terminal 25 and the separator 21 can be reduced.

In the fuel cell stack 100, the cell voltage can be easily measured simply by bringing the voltage probe into contact with the pair of voltage terminals 25. Further, since the contact resistance between the voltage terminal 25 and the separator 21 is kept small, the measurement error of the cell voltage can be suppressed small, and the accurate measurement of the cell voltage becomes possible. Also, in the case where the cell voltage is measured using the voltage measurement line 19 as in the conventional stacked fuel cell, the voltage measurement line 1
9 can be dealt with by soldering to the main part 25a of the voltage terminal 25. Therefore, it is not necessary to form the hole 10 for attaching the voltage measurement line unlike the conventional separator 1. Thereby, the strength of the separator 21 is ensured, so that the thickness of the separator 21 can be reduced, and the stacked fuel cell can be made compact. Further, the conventional drilling process and the bonding operation of the voltage measurement line 19 are not required, and the measurement operation of the cell voltage is simplified.

Embodiment 2 FIG. 6 is a side view showing a stacked fuel cell according to Embodiment 2 of the present invention. FIGS. 7 and 8 show a first separator applied to the stacked fuel cell according to Embodiment 2 of the present invention. FIG. 9 and FIG. 10 are perspective views showing a state seen from the first main surface side and the first opposing surface side. FIGS. 9 and 10 show a second separator applied to the stacked fuel cell according to Embodiment 2 of the present invention, respectively. FIG. 11 is a perspective view showing a state seen from the side and the second main surface side. FIG. 11 is a perspective view showing a state in which voltage terminals are mounted on a separator applied to the stacked fuel cell according to Embodiment 2 of the present invention.
FIG. 4 is a cross-sectional view showing a main part of a stacked fuel cell according to Embodiment 2 of the present invention.

Referring to FIG. 6, a stacked fuel cell 101 includes:
A laminated body 30 is formed by alternately laminating a predetermined number of electrode / membrane assemblies 15 as single cells and separators including first and second separators 31 and 35, and are disposed at both ends of the laminated body 30 in the laminating direction. End plate 16 and current collecting electrodes 17 and 18 interposed between the laminate 30 and the end plate 16. Then, the laminate 30, the collecting electrodes 17, 1
The end plate 8 and the end plate 16 are integrally fastened by a fastening bolt (not shown). Note that this stacked fuel cell 1
01 has the same configuration as the above-described stacked fuel cell 100 except that a separator composed of first and second separators 31 and 32 is used instead of the separator 21.

Here, the structure of the first separator 31 and the voltage terminal 25 will be described with reference to FIGS. The first separator 31 is made of carbon, and is formed in a flat plate shape having two opposing surfaces as a quadrangular first main surface 31a and a first opposing surface 31b. Then, the peripheral gas seal portions 32a and 32b
The first main surface 31a and the first opposing surface 31b of the first separator 31 are formed on the outer peripheral portions of the main surface 31a and the first opposing surface 31b, respectively, and are surrounded by the peripheral gas seal portions 32a and 32b. And a cooling portion 33b. The engaging recess 34 is formed in an L shape so as to extend from the peripheral gas seal portion 22a of the first main surface 31a of the first separator 31 to the side surface 31c. The engaging concave portion 34 includes a concave portion 34a having a depth of 0.35 mm formed in the peripheral gas seal portion 32a and a concave portion 34b having a depth of 0.3 mm formed in the side surface 31c. The voltage terminal 25 is formed by bending a tin-plated iron plate having a thickness of 0.3 mm and a length of 20 mm and having a spring property and connecting a pair of side portions 25b and 25c with a main portion 25a to form a U-shape. ing. And a pair of side part 25b,
25c is the thickness of the engaging recess 34 (the recess 34
(a thickness between the bottom surface of a and the first opposing surface 32b), and is formed so that the interval on the distal end side is reduced.

The oxidizing gas inlet manifold 4, the oxidizing gas outlet manifold 5, the fuel gas inlet manifold 6, the fuel gas outlet manifold 7, the cooling water inlet manifold 8, and the cooling water outlet manifold 9 include peripheral gas seal portions 32a, 32b. Are provided through the first separator 31. Bolt insertion holes 13 for fastening bolts are formed at four corners of the first separator 31. The first main surface 31a is arranged such that the fuel gas passage groove 11 communicates the fuel gas inlet manifold 6 and the fuel gas outlet manifold 7.
Is formed in the reaction part 33a. Also, the first facing surface 3
1b is a flat surface.

Next, the structure of the second separator 35 will be described with reference to FIGS. The second separator 35 is made of carbon, and is formed in a flat plate shape having two opposing surfaces as a quadrangular second facing surface 35a and a second main surface 35b. Then, the peripheral gas seal portion 36
a and 36b are formed on the outer periphery of the second facing surface 35a and the second main surface 35b of the second separator 35, respectively, and the second facing surface 35a and the second separator 35 of the second separator 35 surrounded by the peripheral gas seal portions 36a and 36b. The portion of the second main surface 35b forms a cooling section 37a and a reaction section 37b.
An engagement recess 38 is formed on the second facing surface 35a of the second separator 35. This engagement recess 38 is
It is constituted by a concave portion 38a having a depth of 0.35 mm which is concavely provided on the peripheral surface gas seal portion 36a of the facing surface 35a so as to reach the side surface 35c.

The oxidizing gas inlet manifold 4, the oxidizing gas outlet manifold 5, the fuel gas inlet manifold 6, the fuel gas outlet manifold 7, the cooling water inlet manifold 8, and the cooling water outlet manifold 9 include peripheral gas seal portions 36a, 36b. Are provided through the second separator 35. Bolt insertion holes 13 for fastening bolts are formed at four corners of the second separator 35. And
The oxidizing gas passage groove 12 is formed in the oxidizing gas inlet manifold 4.
And the oxidizing gas outlet manifold 5 are formed in the reaction section 37b of the second main surface 35b. In addition, the cooling water passage groove 39 is provided with the cooling water gas inlet manifold 8.
The cooling portion 37a of the second facing surface 35a is formed so as to communicate with the cooling water outlet manifold 9.

The voltage terminal 25 is connected to the pair of side portions 2.
5b and 25c are inserted into the engagement recesses 34 while pushing the leading ends thereof apart. Therefore, as shown in FIGS. 11 and 12, the voltage terminal 25 is connected to a pair of side portions 25b, 25b.
c comes into surface contact with the bottom surface of the concave portion 34a and the peripheral gas seal portion 32b, and the main portion 25a comes into surface contact with the bottom surface of the concave portion 34b. At this time, the spring force of the pair of side portions 25b and 25c prevents the voltage terminal 25 from coming off from the first separator 31, and maintains the surface contact between the voltage terminal 25 and the first separator 31. . Further, the main portion 25a and the side surface 31c are at the same plane position, the side portion 25b is stored in the recess 34a, and the side portion 25c is stored in the recess 38a.

Therefore, also in the second embodiment, the voltage terminal 25 is connected to the first separator 31 due to its spring property.
The electrical connection is made while keeping the contact resistance small since the mounting recess 34 is attached to the engaging recess 34 in a good surface contact state.
Further, since the voltage terminal 25 is made of a U-shaped metal piece having a spring property, the voltage terminal 25 is connected to the first separator 3.
1 can be easily mounted. Also, the voltage terminal 25
Is stored in the recess 34a of the engaging recess 34 of the first separator 31 and does not protrude from the first main surface 31a, so that the electrode / membrane assembly 15 is No damage. Further, since the engagement recesses 34 and 38 are formed in the first and second separators 31 and 35, the plate thickness of the voltage terminal 25 can be increased by that amount, and the spring property of the voltage terminal 25 can be enhanced. it can. Thereby, the contact resistance between the voltage terminal 25 and the first separator 31 can be reduced.

Also in this stacked fuel cell 101, the cell voltage can be easily measured only by bringing the voltage probe into contact with the pair of voltage terminals 25. Further, since the contact resistance between the voltage terminal 25 and the first separator 31 is kept small, the measurement error of the cell voltage can be kept small. Also, in the case where the voltage measurement line 19 is attached and the cell voltage is measured similarly to the conventional stacked fuel cell, the voltage measurement line 19 is connected to the main part 2 of the voltage terminal 25.
It can be dealt with by soldering to 5a. Therefore, it is not necessary to form the hole 10 for attaching the voltage measurement line unlike the conventional separator 1. As a result, similarly to the first embodiment, the stacked fuel cell can be made compact, and the operation of measuring the cell voltage can be simplified.

The side portion 25c of the voltage terminal 25 is
Since it is housed in the recess 38a of the engagement recess 38 of the separator 35 and does not protrude from the second main surface 35b, even if the voltage terminal 25 is mounted, the first and second separators 31,
The first and second opposing surfaces 31b and 35a of 35 are in close contact with each other, and there is no leakage of cooling water flowing through the cooling water channel groove 39.
Further, the separators are first and second separators 31, 3
5, the cooling water channel groove 39 can be easily configured. Also, the second separator 35
A voltage terminal 25 is attached to the peripheral gas seal portion 36a of the facing surface 35a.
Is provided with an engagement recess 38 for accommodating the side portion 25c, and the first facing surface 31 of the first separator 31 in which the side portion 25c is in close contact.
Since the peripheral gas seal portion 32b of b is a flat surface,
The mechanical strength of the engagement recess 24 of the first separator 31 can be increased.

In the second embodiment, the cooling water passage groove 39 is formed in each separator (each second separator 35). However, the cooling water passage groove 39 is not necessarily formed in each separator. However, it is only necessary that they are formed on the separator every several cells. In this case, the second separator 35 having no cooling water passage groove 39 is formed.
The facing surface 35a is a flat surface. Embodiment 2
Although the cooling water passage groove 39 is formed in the second separator 35 in the embodiment, the cooling water passage groove 39 may be formed in the first separator 31. Further, in the stacked fuel cell 100 according to Embodiment 1, in order to suppress the temperature rise of the battery, the separator 21 for every several cells is used instead of the separator including the first and second separators 31 and 35. Is also good.

Embodiment 3 FIG. FIG. 13 is a perspective view showing a separator applied to the fuel cell stack according to Embodiment 3 of the present invention. In FIG. 13, the engagement recess 34A
Are formed in an L shape so as to extend from the peripheral gas seal portion 22a of the first main surface 31a of the first separator 31A to the side surface 31c. Although not shown, the engagement recess 34A has a depth of 0.1 mm formed in the peripheral gas seal portion 32a.
3 mm recess and 0.3 m depth recessed in side surface 31c
m concave portions. Also, the engagement recess 38A
Are formed in an L shape so as to extend from the peripheral gas seal portion 36b of the second main surface 35b of the second separator 35A to the side surface 35c. Although not shown, the engagement recess 38A has a depth of 0.1 mm formed in the peripheral gas seal portion 36b.
3 mm recess and 0.3 m depth recessed in side surface 35 c
m concave portions.

The voltage terminal 25 has a thickness of 0.3 mm and a length of 2 mm.
It is formed in a U-shape formed by bending a tin-plated steel plate having a spring property of 0 mm and connecting a pair of side portions 25b and 25c by a main portion 25a. Then, the pair of side portions 25b, 25c adjust the interval between the root portions to the engagement concave portions 34A, 38.
A is formed so as to have a thickness equal to the thickness of A (the thickness between the concave portions formed on the first and second main surfaces 31a and 35b) and to reduce the interval on the tip side. The other configuration is the same as that of the second embodiment.

In the third embodiment, the voltage terminal 25
Due to its spring property, the first and second separators 31A,
It is attached to the engagement recesses 34A, 38A of 35A in good surface contact. The pair of side portions 2 of the voltage terminal 25
5b and 25c are the first main surface 31a and the second main surface 35
It is located on the same plane as b. Therefore, also in the third embodiment, the same effects as in the second embodiment can be obtained. Also, according to the third embodiment, the first and second
Since the separators 31A and 35A are integrated by the voltage terminal 25, the assemblability of the stacked fuel cell is improved. In addition, since the electrical resistance between the first and second separators 31A and 35A is kept low, the power generation loss of the stacked fuel cell can be suppressed.

Embodiment 4 FIG. 14 is a perspective view showing a separator applied to the fuel cell stack according to Embodiment 4 of the present invention. In FIG. 14, the engagement recess 34A
Are formed at diagonal positions on the first separator 31B. Similarly, the engagement recess 38A is provided in the second separator 35B.
Are formed at diagonal positions. And the first and second
Separators 31B and 35B are engaged with engagement recesses 34 at diagonal positions.
A and 38A are integrally connected by two voltage terminals 25 attached thereto. The other configuration is the same as that of the third embodiment.
It is configured similarly to.

According to the fourth embodiment, the first and second separators 31B and 35B are integrally connected at the diagonal positions by the two voltage terminals 25. First and second separators 31B, 35
B is more firmly integrated. Similarly, the contact electric resistance between the first and second separators 31B and 35B becomes smaller.

Embodiment 5 FIG. 15 is a diagram showing voltage terminals mounted on the separator of the stacked fuel cell according to Embodiment 5 of the present invention. FIG. 15 (a) is a front view thereof, and FIG. 15 (b) is a cross section thereof. FIG. FIG. 16 is a fragmentary cross-sectional view for explaining a mounting state of voltage measurement lines in the stacked fuel cell according to Embodiment 5 of the present invention. FIG.
, The voltage terminal 40 has a thickness of 0.3 mm and a length of 20 mm.
mm tin-plated spring-like iron plate is bent to form a U-shape formed by connecting a pair of side portions 40b and 40c with a main portion 40a.
0a, and a hole 40e is formed in the center of the projection 40d. And a pair of side part 40b,
40c is formed so that the interval between the roots is equal to the thickness of the engaging concave portion formed in the spacer, and the interval on the distal end side is reduced. Here, a convex portion 40d in which a hole 40e is formed
Constitute a mounting portion of the voltage measurement line 19.

The voltage terminals 40 are easily manufactured by press punching. That is, a single iron plate is punched into a rectangle, and a hole 40e is formed in the center. next,
A convex portion 40d is formed at the center by die pressing, and the side portions 40b and 40c are formed by bending. Finally, tin plating is performed to obtain the voltage terminal 40. As described above, the voltage terminal 40 can be manufactured at a low cost similarly to the clip used for office work.

The voltage terminal 40 thus manufactured is mounted on the separator 21 instead of the voltage terminal 25, as shown in FIG. Then, the voltage measurement line 19 is inserted into the hole 40e by peeling off the insulating coating at the end thereof,
It is connected to the voltage terminal 40 by solder 41. Here, the protrusion 40d secures a space for accommodating the tip of the voltage measurement line 19 inserted into the hole 40e. And since the convex part 40d which becomes high temperature at the time of soldering is separated from the separator 21, heat is not easily transmitted to the separator 21, and the heating of the separator 21 is prevented. In addition,
After the voltage measurement wire 19 is soldered to the voltage terminal 40, the voltage terminal 40 can be easily attached to the separator 21. Further, since the convex portion 40d in which the hole 40e is formed is formed in the main portion 40a of the voltage terminal 40, the voltage measurement line 1
9 can be easily soldered. Therefore, the voltage measurement line 19 is less likely to come off from the voltage terminal 40, and accurate voltage measurement can be performed even when the stacked fuel cell is exposed to vibration and environmental changes. In addition, since the pair of side portions 40b and 40c are formed so that the distal ends are narrowed, the spring property of the voltage terminal 40 causes the electrical connection between the voltage terminal 40 and the separator 21 as in the first embodiment. Contact is realized with low contact resistance.

In the fifth embodiment, the voltage terminal 40 is used instead of the voltage terminal 25 in the first embodiment. However, the fifth embodiment may be applied to the second to fourth embodiments. Further, in the fifth embodiment, the hemispherical projection 40d having the hole 40e formed therein is formed by press working on the main portion 40a to form the mounting portion for the voltage measurement line 19, but the mounting portion is formed. Is not limited to this, and a cut-and-raised piece formed by cutting and raising a part of the main portion 40d may be used as the attachment portion.

Embodiment 6 FIG. FIG. 17 is a side view showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 6 of the present invention, and FIG. 18 is a diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 6 of the present invention. FIG. 18 shows a state where the stacked fuel cell shown in FIG. 17 is rotated by 90 degrees. FIG. 19 is a partially cut-away side view showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 6 of the present invention, and FIG. 20 is a view of a cell voltage in a stacked fuel cell according to Embodiment 6 of the present invention. It is a schematic circuit diagram which shows a measuring method.

Referring to FIGS. 17 to 20, the stacked fuel cell 102 includes the electrode / membrane assembly 15 as a single cell and the first
And a separator 30 formed by alternately laminating a predetermined number of second and third separators 31 and 35;
End plates 16 respectively disposed at both ends in the stacking direction of the above, current collector electrodes 17 interposed between the stacked body 30 and the end plates 16,
18. The laminated body 30, the current collecting electrodes 17, 18 and the end plate 16 are integrally fastened by a fastening bolt (not shown). The stacked fuel cell 102 has a voltage terminal 4 instead of the voltage terminal 25.
0A, except that the above-described stacked fuel cell 1
It is configured in the same way as 01. Here, the voltage terminal 40A
Is the one in which the hole 40e in the voltage terminal 40 described above is omitted.

The voltage measuring device 50 is attached to a pair of end plates 16 via an insulating member 51, and is separated from the laminated body 30 by a rail 52 extending in the laminating direction of the laminated body 30.
A movable body 53 attached to the rail 52 so as to be able to reciprocate in the longitudinal direction of the rail 52;
And the other end is fixed to the movable body 53,
A coil spring 54 for urging the movable body 53 toward one end of the rail 52, a rotating reel 55 rotatably attached to the movable body 53, and a yarn winding reel 56 rotatably attached to the other end of the rail 52; A movable member 5, one end of which is fixed to the other end of the rail 52, and which is hung over a rotating reel 55 and the other end of which is fixed to a yarn take-up reel 56.
3 and a movable body 53
Terminal 59, a negative contact 60 electrically connected to the negative terminal 58, and a positive contact electrically attached to the positive terminal 59. 61.

The minus terminal 58 and the plus terminal 59 are attached to the movable body 53 such that the distance between them can be adjusted by the top 62. Here, the distance between the negative terminal 58 and the positive terminal 59 is adjusted to the distance between the protrusions 40d of the adjacent electrode terminals 40A. The negative contact 60 and the positive contact 61 are made of thin metal pieces having elasticity. Further, a first movable probe 63 is constituted by the minus terminal 58 and the minus contact 60, and a second movable probe 64 is constituted by the plus terminal 59 and the plus contact 61.

The negative and positive fixed probes 65 and 66 are attached to the current collecting electrodes 17 and 18, respectively, and the voltage measurement line 19 is connected to the first and second movable probes 63 and 64 and the fixed probes 65 and 66, respectively. To form the voltage measuring circuit shown in FIG.

Here, the coil spring 54 and the rotating reel 5
5, the movable body 53 from the yarn winding reel 56 and the yarn 57
Of moving means. Then, by rotating the yarn winding reel 56 in one direction, the yarn 57 is wound on the yarn winding reel 56, and the movable body 53 is guided by the rail 52 against the urging force of the coil spring 54, and the other end is Go to When the yarn winding reel 56 is rotated in the other direction, the yarn 57 is unwound from the yarn winding reel 56, and the movable body 53 is guided to the rail 52 by the urging force of the coil spring 54 and moves to one end. In this manner, the cell voltage at the plus end is measured when the yarn 47 is most unreeled, and the cell voltage at the minus end is measured when the yarn 47 is most wound. That is, the cell measured by the length of the thread 47 is determined. Therefore, which cell voltage is to be measured can be controlled by the rotation speed and rotation angle of the yarn winding reel 56. Such a moving means is often used in a pen recorder, and can be controlled accurately and at a low cost.

Next, a cell voltage measuring method according to the sixth embodiment will be described. The movable body 53 moves to one side in the stacking direction of the stack 30 by rotating the yarn winding reel 56 by a drive motor (not shown). Accordingly, the negative contact 60 and the positive contact 61 respectively extend from the movable body 53 so as to be orthogonal to the laminating direction of the laminated body 30, and elastically deform when hitting the convex portion 40 d of the voltage terminal 40 A. While moving over the outer peripheral surface of the convex portion 40d while sliding over the convex portion 40d, it returns to the original state due to its elasticity. At this time, since the interval between the negative contact 60 and the positive contact 61 is equal to the interval between the convex portions 40d of the adjacent voltage terminals 40A,
The negative contact 60 and the positive contact 61 are electrically in contact with the convex portions 40d of the adjacent electrode terminals 40A, respectively. The negative side of the electrode / membrane assembly 15 is picked up by the negative contact 60 via the separators 35 and 31 and the voltage terminal 40A, and communicates with the voltage measurement line 19 via the negative terminal 58. Similarly, the electrode / membrane assembly 15
Is picked up by the positive contact 61 via the separator 31 and the voltage terminal 40A, and the positive terminal 59
Through to the voltage measurement line 19. By measuring the voltage between the two voltage measurement lines 19, the voltage (V1) generated on the front and back of the electrode / membrane assembly 15 (single cell) is obtained.

Further, by measuring the voltage between the voltage measurement line 19 connected to the plus terminal 59 and the voltage measurement line 19 connected to the plus fixed probe 66, the voltage of the measured cell can be reduced. A positive voltage (V2) is obtained. Further, by measuring the voltage between the voltage measurement line 19 connected to the negative terminal 58 and the voltage measurement line 19 connected to the negative fixed probe 65, the voltage on the negative side of the measured cell voltage is measured. The voltage (V3) is obtained.

The three voltages V1 thus obtained,
From V2 and V3, it is determined whether there is any abnormality in the cell voltage (V1) being measured, and the voltage (V1 + V2) of the entire stacked fuel cell is determined.
+ V3) is obtained. In addition, (V1 + V2 + V3) is divided by the total number of cells to obtain a voltage (V
By comparing with 1), the deviation of the voltage of the cell being measured from the average value is instantaneously determined. Further, the voltage V2
Is divided by the number of cells constituting the voltage V2 to obtain a voltage V1
By comparing with, it is determined whether or not an abnormal cell is included on the positive side of the voltage V1. Similarly, the voltage V3
Is divided by the number of cells constituting the voltage V3 to obtain a voltage V1.
By comparing with, it is determined whether or not an abnormal cell is included on the negative side of the voltage V1. Thus, 3
By monitoring two voltages (V1, V2, V3)
It is possible to grasp the entire stacked fuel cell.

The movable part 53 is periodically or
By moving the cell as needed, it is possible to monitor the voltages of all the cells. Further, the voltages V1, V2, V3
, It is determined whether there is a low voltage cell on the plus side or the minus side with respect to the cell being measured. Therefore, by moving the movable portion 53 to the side where the low-voltage cell is located, the low-voltage cell can be detected and the low-voltage cell can be monitored.

According to the sixth embodiment, by measuring three voltages, it is possible to monitor which cell has the lowest voltage, to monitor the voltage of the entire stacked fuel cell, and to further measure the voltage. Since it is possible to monitor the plus side and the minus side of an existing cell, it has an ability comparable to measuring the voltage of all cells. Further, the voltage terminal 40A is attached to the engagement recess 34 of the separator 31 with low electric contact resistance due to its elasticity, and the voltage measurement line 1
Since all electrical connections up to 9 are metal-to-metal contacts, the electrical contact resistance in the measurement path is kept small, cell voltage measurement errors are reduced, and cell voltage can be measured with high accuracy. it can.

Further, a convex portion 40d is provided on the main portion 40a of the voltage terminal 40A, and the movable body 53 is arranged so as not to contact the side of the laminate 30 when the contacts 60 and 61 are separated from the convex portion 40d. So that the contacts 60 and 61 are
The cell voltage is measured only when it is in contact with d, and the cell voltage can be reliably measured.

The cell voltage can be constantly monitored by measuring the cell voltage at regular intervals or based on predetermined conditions by using the control device, so that the abnormal cell can be found early. Become.

Embodiment 7 FIG. 21 is a schematic circuit diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 7 of the present invention. In the seventh embodiment, in the voltage measuring device 50 of the sixth embodiment,
2, the distance between the negative terminal 58 and the positive terminal 59 is adjusted to be equal to the distance of three cells. Then, as shown in FIG. 21, the voltage (V1) of the three cells, the voltage (V2) between the second movable probe 64 and the positive fixed probe 66, and the first movable probe 6
Voltage between V3 and negative fixed probe 65 (V3)
And has been measured. Therefore, also in the seventh embodiment, since three voltages are measured, the sixth embodiment is used.
The same effect can be obtained.

In the seventh embodiment, the voltage V1 of three cells is measured.
Is not limited to the voltage of three cells, and may be set as needed. For example, a voltage of two cells or a voltage of four cells may be used. The voltage measuring device 50 can easily respond by adjusting the distance between the negative terminal 58 and the positive terminal 59 according to the set number of cells. Also,
A large number of movable bodies with different intervals between the minus side terminal 58 and the plus side terminal 59 may be prepared, and a movable body corresponding to the set number of cells may be selected and attached.

Embodiment 8 FIG. FIG. 22 is a schematic circuit diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 8 of the present invention. In the stacked fuel cell 102 according to the seventh embodiment, the voltage terminals 40A are mounted on the first separators 31. However, in the stacked fuel cell 102A according to the eighth embodiment, the voltage terminals 40A
Are attached to the first separators 31 for every three cells. According to the eighth embodiment, in addition to the effect of the seventh embodiment, the number of voltage terminals 40A is reduced,
Cost reduction is achieved.

Embodiment 9 FIG. 23 is a schematic circuit diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 9 of the present invention. In the ninth embodiment, as shown in FIG. 23, for example, the first movable probe 63 is omitted from the seventh embodiment, and the distance between the second movable probe 64 and the plus side fixed probe 66 is increased. (V1) and the voltage (V2) between the second movable probe 64 and the minus fixed probe 65 are measured.

In the ninth embodiment, the difference between the value obtained by dividing the voltage (V1 + V2) of the entire stacked fuel cell by the number of cells and the value obtained by dividing the voltage on the plus side and the minus side by the number of cells is determined. be able to. Therefore, it is possible to determine whether the cell voltage is lower than the average value on the plus side or the minus side. Then, by moving the movable portion 53, the number of cells on the plus side and the minus side can be changed, so that a cell having a low cell voltage can be specified. Furthermore, if the movable section 53 is moved in a state where the cell voltage is stable, the voltage of a specific cell can be estimated from the voltage difference from the case where the cell is shifted by one cell. Further, when the movable portion 53 is quickly moved, V
From the changes in the voltages of 1 and V2, it becomes possible to estimate all cell voltages almost accurately. That is, by monitoring only two voltages, it becomes possible to measure all cell voltages almost accurately. Further, even when it is desired to constantly monitor the voltage of a specific cell, if the movable portion 53 is repeatedly moved back and forth before and after the cell, the voltage of the specific cell is monitored in a state close to that of the constant monitoring from the voltage difference between V1 and V2. It becomes possible to do. Therefore, although the cell voltage cannot be accurately measured, the cost can be reduced by reducing the number of voltage terminals of the monitor.

Embodiment 10 FIG. FIG. 24 is a schematic circuit diagram showing a method for measuring a cell voltage in the stacked fuel cell according to Embodiment 10 of the present invention. In the tenth embodiment, as shown in FIG. 24, a third movable probe 67 is added to the sixth embodiment. And
The first movable probe 63, the second movable probe 64, and the third movable probe 67 are arranged at intervals of one cell. Therefore, according to the tenth embodiment, adjacent two
The voltage of one cell can be monitored. As described above, when it becomes possible to constantly monitor two adjacent cells, the voltage V3
Is divided by the number of cells (the number of cells constituting the voltage V3) and the average cell voltage obtained by dividing the voltage V4 by the number of cells (the number of cells constituting the voltage V4). Can be directly compared, and it is easy to determine whether the cell voltage of the voltage V1 or the voltage V2 is normal or abnormal. The tenth embodiment is particularly effective when the number of stacked fuel cells 102 is extremely large.

Embodiment 11 FIG. FIG. 25 is a schematic circuit diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 11 of the present invention. In the stacked fuel cell 103 of the eleventh embodiment, the voltage terminals 40A are mounted on two opposite sides of the first separator 31 and at diagonal positions, respectively, and the voltage terminals 40A are connected to the two opposite sides of the stacked body 30.
The sides are arranged in the stacking direction. Then, as shown in FIG. 25, two sets of voltage measuring devices 50 are attached to the two sets of stacked fuel cells 103 along a group of two voltage terminals 40A arranged in the stacking direction.

According to the eleventh embodiment, it is possible to constantly monitor the cell voltages at two different places of the stacked fuel cell 103. Further, the time required to finish measuring the entire cell voltage is reduced by half. Further, even when an abnormality is detected, it is possible to check whether the abnormality is caused by an abnormality of the measurement point or the voltage measurement line 19. Further, from a subtle difference between the cell voltages of the voltage V1 and the voltage V5, it is possible to detect an abnormality of the cell. That is, when a corrosion reaction or a large current drift occurs, a situation occurs in which the cell voltage differs depending on the location of the stacked body 30. This makes it possible to determine whether an abnormality has begun to occur in the cell before the cell voltage drops significantly. The phenomenon that the cell voltage varies depending on the location when abnormal
Since the larger the two monitored points are, the larger the distance between them, the voltage V1 and the voltage V5 are preferably at two different sides of the stacked body 30, preferably at diagonal positions.

Embodiment 12 FIG. FIG. 26 is a side view showing a stacked fuel cell according to Embodiment 12 of the present invention.
In FIG. 26, the stacked fuel cell 104 has an electrically insulating coating 60 made of a silicone resin coated on the stacked body 30. The other configuration is the same as that of the above-described stacked fuel cell 102.
It has the same configuration as A. This electrical insulation coating 60
After applying a silicone sealant (registered trademark of Shin-Etsu Chemical Co., Ltd.) made of paste-like silicone rubber to the side surfaces of the laminate 30 other than the protrusions 40d of the voltage terminals 40A, the fuel inlet, the oxidant inlet, and the cooling of the laminate 30 are applied. Water inlet total 3
The joints at the three locations were covered with a lid, and exhausted from a total of three locations, a fuel outlet, an oxidant outlet, and a cooling water outlet, using an air exhaust pump to reduce the internal pressure of the stacked body 30 to a negative pressure for one hour. It is formed by drying, solidifying and then returning to normal pressure. The electric insulating coating 6 thus formed
Numeral 0 is coated on the four side surfaces excluding both end portions of the laminated body 30 (both end portions of the end plate 16) and the convex portion 40d of the voltage terminal 40A.

According to the twelfth embodiment, the laminate 30
There is no danger of electric shock even when touching the side of the laminate, and the cushion is covered with silicone rubber, so that the entire side of the laminate 30 can be protected from physical impact and the separator can be prevented from cracking. . Furthermore, the heat insulation of the laminated body 30 is improved by the heat insulating property of silicone rubber,
Heat radiation loss can be reduced. In addition, since the silicone rubber can be easily removed from the laminate 30 and can be treated as many times as possible, there is no danger of rearrangement of the laminate 30 such as replacement of the separator or the electrode / membrane assembly. Also, even if there is a gas leak in the peripheral gas seal portion, when the inside of the laminate 30 is made to have a negative pressure, the silicone rubber is sucked into the gas leak and solidified, and the gas leak can be stopped. .

In the twelfth embodiment, the case where silicone rubber is used as the electrical insulating coating 60 is shown. However, even if the electrical insulating coating 60 is not made of silicone rubber, a silicone resin, a fluororesin, an acrylic resin, Similar effects can be obtained by using rubber or the like.

In each of the above embodiments, the case of a polymer electrolyte fuel cell has been mainly described. However, the same effect can be obtained in a phosphoric acid fuel cell, a methanol direct fuel cell, a dimethyl ether direct fuel cell, or the like. can get.

In the sixth to twelfth embodiments, the stacked fuel cell according to the second embodiment is described as being applied to the stacked fuel cell in which the voltage terminal 40A is used in place of the voltage terminal 25. In the stacked fuel cells according to the first, third, and fourth embodiments, the same effect can be obtained even when the voltage terminal 40A is used in place of the voltage terminal 25. Further, in each of the above-described embodiments, the case of the carbon separator has been described, but the same effect can be obtained in the case of the metal separator.

[0086]

Since the present invention is configured as described above, it has the following effects.

According to the present invention, there is provided a laminate type comprising a laminate formed by alternately laminating a single cell integrally joined by sandwiching an electrolyte membrane between a fuel electrode and an oxidant electrode, and a separator. In the fuel cell, a voltage terminal formed in a U-shape by connecting a pair of side portions of a metal plate having a spring property by a main portion is provided on a part of the side surface of the separator, the main portion and the side portion. Since the portion is sandwiched so as to be in contact with the side surface of the separator and both surfaces of the front and back, electrical contact resistance between the separator and the voltage terminal can be kept small,
A stacked fuel cell that can easily measure the cell voltage by simply bringing the voltage probe into contact with the voltage terminal is obtained.

Further, since the recesses for accommodating the pair of side portions of the voltage terminal are respectively recessed on both the front and back surfaces of the separator, the thickness of the voltage terminal can be increased, and the spring property of the voltage terminal can be increased. And the electrical contact resistance between the separator and the voltage terminal further decreases.

Further, the separator comprises a first separator having a fuel gas passage groove formed on a main surface thereof, and a second separator having an oxidizing gas flow passage groove formed on a main surface thereof. The voltage terminals are connected to the first side by the first side.
Further, since the battery is sandwiched so as to be in contact with the main surfaces of the second separator, the assemblability of the stacked or perennial battery is improved, and the electric resistance between the first and second separators is reduced.

Further, the separator has a first separator having a fuel gas flow channel formed on a main surface thereof and a second separator having an oxidizing gas flow channel formed on a main surface thereof, which is opposed to the main surface on the opposite side. The voltage terminals are connected to the first side by the first side.
And a concave portion for accommodating one side of the pair of side portions is provided on the main surface of the one separator so as to be in contact with the main surface and the opposing surface of the one separator of the second separator, respectively. Since the recessed portion for receiving the other side is recessed on the opposite surface of the other of the first and second separators, the recessed portion is formed only on one of the front and back surfaces of the first separator. What should I do, first
The mechanical strength of the separator increases.

Further, since the voltage terminals are sandwiched between the separators every several cells, the number of voltage terminals can be reduced and the cost can be reduced.

Further, since the voltage terminals are sandwiched between two opposite sides of the separator and substantially at diagonal positions, when an abnormality in the cell voltage is detected, an abnormality in the measurement point or the measurement line is detected. Can be determined. In addition, 2
It is also possible to detect an abnormality of the cell from a subtle difference in the cell voltage at a location.

Further, since the electrical insulating coating is coated on the side surface of the laminate so as to expose at least a part of the main portion of the voltage terminal, a short circuit accident is prevented.

Further, since the above-mentioned electric insulating coating is formed by applying silicone rubber, elasticity is given to the side surface of the laminated body, so that the separator is prevented from being cracked by a physical impact. Since the electrical insulation coating has thermal insulation,
The laminate can be kept warm. Since the silicone rubber is translucent, it is possible to observe the state of the side surface of the laminate and detect a problem such as water leakage.

Further, the electric insulating coating is such that a liquid or paste-like silicone rubber is applied to the side surface of the laminate so that at least a part of the main part of the voltage terminal is exposed, and the pressure inside the laminate is reduced. After the negative pressure is applied, the silicone rubber is dried and solidified, and then the interior of the laminate is returned to normal pressure, so that the silicone rubber permeates and solidifies in a portion where the seal leaks, thereby improving the gas sealing property. Is done.

Also, since the voltage measuring line mounting portion is formed in the main portion of the voltage terminal, and the voltage measuring line is soldered to the mounting portion, the voltage measuring line is protected against vibration and environmental changes. Is secured, and the reliability of voltage measurement is improved.

Further, according to the present invention, there is provided a laminated body constituted by alternately laminating a single cell integrally joined by sandwiching an electrolyte membrane between a fuel electrode and an oxidant electrode, and a separator. In a method for measuring a cell voltage of a stacked fuel cell,
A metal plate having a U-shape spring property formed by connecting a pair of side portions by a main portion is provided on a part of the side surface of the separator, and the main portion and the side portion are formed on both the side surface and the front and back surfaces of the separator. The voltage terminals are sandwiched so as to be in contact with the respective voltage terminals, and the voltage measurement line is electrically contacted with the voltage terminals to measure the voltage of each single cell or several cells. A method for measuring the cell voltage of a stacked fuel cell that can easily and easily measure the cell voltage is obtained.

Further, a pair of movable probes are mounted on the side surface of the laminated body so as to be movable in the laminating direction of the laminated body, and the pair of movable probes are respectively moved to connect to the two voltage terminals arbitrarily selected. Since they are brought into contact with each other and the cell voltage is measured, the number of voltage measurement lines can be greatly reduced.

Further, a pair of fixed probes are fixed to both ends of the laminate, respectively, and one movable probe is
The movable body is attached to a side surface of the laminate so as to be movable in the laminating direction of the laminate, and the movable probe is moved so as to be in contact with the arbitrarily selected voltage terminal. Since the voltage is measured, the average cell voltage on both the positive side and the negative side of the movable probe is grasped, and it is possible to determine which includes a cell having a low cell voltage.

Further, a pair of movable probes set at an interval between the adjacent voltage terminals are movably attached to the side surface of the laminate in the direction of lamination of the laminate, and the pair of movable probes are moved. Since each of the adjacent voltage terminals is contacted and the cell voltage of any single cell is measured,
Any single cell can be quickly accessed to monitor the cell voltage of the single cell.

Further, a pair of movable probes set at intervals of a plurality of times of the interval between the adjacent voltage terminals are movably attached to the side surfaces of the stacked body in the stacking direction of the stacked body. The probe is moved and brought into contact with the voltage terminals having a plurality of intervals, respectively, and the cell voltage between any number of cells is measured. Can be monitored.

Also, a probe group consisting of at least three movable probes arranged at intervals of a predetermined number of times of the interval between the adjacent voltage terminals can be moved on the side surface of the laminate in the laminating direction of the laminate. Attach, move the probe group to bring each of the movable probes into contact with the voltage terminals, and measure at least two cell voltages.
At least two cell voltages can be monitored at the same time, and the voltage can be measured more quickly. Also, 1
While constantly monitoring one single cell, all other cell voltages can be measured.

Further, the voltage terminals are sandwiched between two opposing sides of the separator and at substantially diagonal positions, respectively, and the movable probe is attached to two opposing side surfaces of the laminate in the laminating direction of the laminate. Since the movable probe is mounted so as to be movable and the movable probe is moved so as to contact the voltage terminals on the two opposite sides of the laminate, the cell voltage of a single cell or every several cells is measured at two points. Is detected, it can be determined whether the measurement point or the measurement line is abnormal. Further, it is possible to detect an abnormality of the cell from a subtle difference between the two cell voltages.

Further, since the convex portion protrudes from the main portion of the voltage terminal and the contact between the voltage terminal and the movable probe is made only by the convex portion, it is possible to measure the voltage more reliably. Can be.

Also, the movable probe is brought into contact with the arbitrarily selected voltage terminal at regular time intervals or according to a command from the control device to measure the voltage of each single cell or several cells. By greatly reducing the number of voltage measurement lines, it becomes possible to measure the cell voltage of a single cell or every several cells. In addition, it is possible to constantly monitor an arbitrary cell voltage, so that there is an effect that it can be used for monitoring for control, early detection of abnormal cells and constant monitoring.

[Brief description of the drawings]

FIG. 1 is a side view showing a stacked fuel cell according to Embodiment 1 of the present invention.

FIG. 2 is a perspective view showing a state in which a separator applied to the stacked fuel cell according to Embodiment 1 of the present invention is viewed from a first main surface side.

FIG. 3 is a perspective view showing a state in which the separator applied to the stacked fuel cell according to Embodiment 1 of the present invention is viewed from a second main surface side.

FIG. 4 is a perspective view showing a separator applied to the stacked fuel cell according to Embodiment 1 of the present invention, in which a voltage terminal is mounted.

FIG. 5 is a sectional view showing a main part of the stacked fuel cell according to Embodiment 1 of the present invention.

FIG. 6 is a side view showing a stacked fuel cell according to Embodiment 2 of the present invention.

FIG. 7 is a perspective view showing a state in which a first separator applied to a stacked fuel cell according to Embodiment 2 of the present invention is viewed from a first main surface side.

FIG. 8 is a perspective view showing a state in which a first separator applied to a stacked fuel cell according to Embodiment 2 of the present invention is viewed from a first facing surface side.

FIG. 9 is a perspective view showing a state where a second separator applied to the stacked fuel cell according to Embodiment 2 of the present invention is viewed from a second facing surface side.

FIG. 10 is a perspective view showing a state in which a second separator applied to the stacked fuel cell according to Embodiment 2 of the present invention is viewed from a second main surface side.

FIG. 11 is a perspective view showing a state in which voltage terminals of a separator applied to the stacked fuel cell according to Embodiment 2 of the present invention are mounted.

FIG. 12 is a cross-sectional view showing a main part of a stacked fuel cell according to Embodiment 2 of the present invention.

FIG. 13 is a perspective view showing a separator applied to a stacked fuel cell according to Embodiment 3 of the present invention.

FIG. 14 is a perspective view showing a separator applied to a stacked fuel cell according to Embodiment 4 of the present invention.

FIG. 15 is a diagram showing voltage terminals mounted on the separator of the stacked fuel cell according to Embodiment 5 of the present invention.

FIG. 16 is a fragmentary cross-sectional view for explaining a mounting state of a voltage measurement line in the stacked fuel cell according to Embodiment 5 of the present invention.

FIG. 17 is a side view showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 6 of the present invention.

FIG. 18 is a side view showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 6 of the present invention.

FIG. 19 is a partially cut-away side view showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 6 of the present invention.

FIG. 20 is a schematic circuit diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 6 of the present invention.

FIG. 21 is a schematic circuit diagram showing a method for measuring a cell voltage in a stacked fuel cell according to Embodiment 7 of the present invention.

FIG. 22 is a schematic circuit diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 8 of the present invention.

FIG. 23 is a schematic circuit diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 9 of the present invention.

FIG. 24 is a schematic circuit diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 10 of the present invention.

FIG. 25 is a schematic circuit diagram showing a method of measuring a cell voltage in a stacked fuel cell according to Embodiment 11 of the present invention.

FIG. 26 is a side view showing a stacked fuel cell according to Embodiment 12 of the present invention.

FIG. 27 is a perspective view of a separator applied to a conventional stacked fuel cell as viewed from a first main surface side.

FIG. 28 is a perspective view of a separator applied to a conventional stacked fuel cell, viewed from a second main surface side.

FIG. 29 is a side view showing a conventional stacked fuel cell.

[Explanation of symbols]

11 fuel gas passage groove, 12 oxidant gas passage groove, 15
Electrode / membrane assembly (single cell), 19 Voltage measurement line, 2
0, 30 laminated body, 21 separator, 21a first main surface, 21b second main surface, 25 voltage terminal, 31, 31
A, 31B first separator, 31a first main surface, 3
1b 1st opposing surface, 35, 35A, 35B 2nd separator, 35a 2nd opposing surface, 35b 2nd main surface, 4
0, 40A voltage terminal, 40d convex part (mounting part), 60
Electrical insulating coating, 63 first movable probe, 64 second movable probe, 65, 66 fixed probe, 67 third movable probe, 100, 101, 102, 102A, 10
3,104 Stacked fuel cell.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Tatsuya Hayashi 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Hideo Maeda 2-3-2 Marunouchi 3-chome, Chiyoda-ku, Tokyo Inside Rishi Electric Co., Ltd. (72) Inventor Hisatoshi Fukumoto 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Sanritsu Electric Co., Ltd. Incorporated F term (reference) 5H026 AA04 AA06 BB03 BB04 CC03 CX08 EE02 EE18 HH03 HH06 HH10 5H027 AA04 AA06 KK54

Claims (19)

[Claims] 1. A stacked fuel cell comprising a stacked body constituted by alternately stacking single cells joined and integrated by sandwiching an electrolyte membrane between a fuel electrode and an oxidant electrode, and a separator, A U-shaped voltage terminal formed by connecting a pair of side portions of a metal plate having a spring property by a main portion is provided on a part of the side surface of the separator. Characterized in that the fuel cell is sandwiched between the side surface and the front and back surfaces of the fuel cell. 2. The stacked fuel cell according to claim 1, wherein concave portions for accommodating a pair of side portions of the voltage terminal are respectively formed on both front and back surfaces of the separator. 3. The separator according to claim 1, wherein the separator has a first separator having a fuel gas flow channel formed on a main surface thereof and a second separator having an oxidant gas flow channel formed on a main surface thereof. The voltage terminals are sandwiched so that the pair of side portions contact the main surfaces of the first and second separators, respectively. The stacked fuel cell according to claim 1 or 2, wherein 4. The separator according to claim 1, wherein the first separator has a fuel gas flow channel formed on a main surface thereof and the second separator has an oxidant gas flow channel formed on a main surface thereof. The voltage terminals connect the pair of side portions to the first and second sides.
A concave portion which is sandwiched so as to be in contact with a main surface and an opposing surface of one of the separators, and which accommodates one side of the pair of side portions, is formed in the main surface of the one separator. 2. The stacked fuel cell according to claim 1, wherein a concave portion for accommodating the other side is formed in a surface of the first and second separators facing the other separator. 5. The stacked fuel cell according to claim 1, wherein the voltage terminal is sandwiched between the separators every several cells. 6. The device according to claim 1, wherein the voltage terminals are sandwiched between two opposite sides of the separator and at substantially diagonal positions. Stacked fuel cell. 7. An electric insulating coating is provided on a side surface of the laminate,
7. The voltage terminal according to claim 1, wherein at least a part of a main part of the voltage terminal is covered.
The stacked fuel cell according to any one of the above. 8. The stacked fuel cell according to claim 7, wherein the electric insulating coating is formed by applying silicone rubber. 9. The electrical insulating coating, wherein a liquid or paste-like silicone rubber is applied to a side surface of the laminate so that at least a part of a main portion of the voltage terminal is exposed, and a pressure inside the laminate is reduced. 9. The stacked fuel cell according to claim 8, wherein the silicone rubber is dried and solidified after negative pressure, and then the inside of the stacked body is returned to normal pressure. 10. The voltage measuring wire according to claim 1, wherein a mounting portion of the voltage measuring wire is formed on a main portion of the voltage terminal, and the voltage measuring wire is soldered to the mounting portion. A stacked fuel cell according to any of the above items. 11. A cell of a stacked fuel cell comprising a single cell integrally joined by sandwiching an electrolyte membrane between a fuel electrode and an oxidant electrode, and a stacked body constituted by alternately stacking separators. In the voltage measuring method, a metal plate having a U-shaped spring property formed by connecting a pair of side portions by a main portion is formed on a part of the side surface of the separator, and the main portion and the side portion are separated by the separator. A voltage terminal is sandwiched so as to be in contact with the side surface and the front and rear surfaces of the cell, respectively, and a voltage measurement line is electrically contacted with the voltage terminal to measure the voltage of each single cell or every several cells. A method for measuring the cell voltage of a stacked fuel cell. 12. A pair of movable probes are movably mounted on a side surface of the laminate in a direction in which the laminates are laminated, and the pair of movable probes are respectively moved to connect two arbitrarily selected voltage terminals. The method for measuring a cell voltage of a stacked fuel cell according to claim 11, wherein the cell voltage is measured by bringing the cells into contact with each other. 13. A pair of fixed probes are fixed to both ends of the laminate, respectively, and one movable probe is attached to a side surface of the laminate so as to be movable in a laminating direction of the laminate. The cell voltage of the stacked fuel cell according to claim 11, wherein the cell voltage is moved and brought into contact with the arbitrarily selected voltage terminal to measure a voltage between the pair of fixed probes and the movable probe. Measuring method. 14. A pair of movable probes set at an interval between the adjacent voltage terminals are movably attached to side surfaces of the laminate in a stacking direction of the laminate, and the pair of movable probes are moved. The method for measuring a cell voltage of a stacked fuel cell according to claim 11, wherein the cell voltage of an arbitrary single cell is measured by bringing the cell into contact with the adjacent voltage terminals. 15. A pair of movable probes set at a plurality of intervals of an interval between adjacent voltage terminals are attached to side surfaces of the laminate so as to be movable in a direction of lamination of the laminate.
12. The stacked fuel cell according to claim 11, wherein the pair of movable probes are moved to make contact with the voltage terminals having the plurality of intervals, respectively, and a cell voltage between any number of cells is measured. How to measure cell voltage. 16. A probe group comprising at least three movable probes arranged at intervals of a predetermined number of times as large as an interval between adjacent voltage terminals so as to be movable on a side surface of the laminate in a direction in which the laminates are laminated. The cell voltage measurement of the stacked fuel cell according to claim 11, wherein the probe group is mounted, and each of the movable probes is brought into contact with each of the voltage terminals to measure at least two cell voltages. Method. 17. The voltage terminal is sandwiched between two opposing sides of the separator and at substantially diagonal positions, and a movable probe is attached to two opposing side surfaces of the laminate in the laminating direction of the laminate. The cell probe is mounted so as to be movable, and the movable probe is moved to contact the voltage terminals on two opposite sides of the laminate, respectively, and a cell voltage of each single cell or every several cells is measured at two points. Item 12. The method for measuring a cell voltage of a stacked fuel cell according to item 11. 18. The device according to claim 1, wherein a convex portion is protruded from a main portion of the voltage terminal, and the contact between the voltage terminal and the movable probe is made only by the convex portion.
A method for measuring a cell voltage of a stacked fuel cell according to any one of claims 2 to 17. 19. The method according to claim 19, wherein the movable probe is brought into contact with an arbitrarily selected voltage terminal at regular intervals or according to a command from a control device to measure the voltage of a single cell or several cells. The method for measuring a cell voltage of a stacked fuel cell according to any one of claims 12 to 18, characterized in that: