JP2006054113A - Connection structure of voltage detection connector to cell and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a connection structure of a voltage detection connector to a cell capable of detecting cell voltages at either end part while restraining the number of parts, cost, a laminating width and weight, and to provide a fuel cell. <P>SOLUTION: To the fuel cell 1 provided with a structure of laminating first cells 2a having a terminal 6 at an anode alone from an anode side end part, and laminating second cells 2b having a terminal 7 at a cathode alone from a cathode side 3 end part, connectors 8, 9 in contact with the terminals 6, 7 are connected. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a connection structure to a cell of a voltage detection connector connected to a fuel cell in which a plurality of cells each having an anode and a cathode are stacked, and detects the voltage of the cell, and a fuel cell.

  In recent years, fuel cells have attracted attention as a new power source for automobiles and the like. The fuel cell includes a membrane electrode structure (MEA) in which an anode electrode (anode) and a cathode electrode (cathode) are disposed on both sides of a solid polymer electrolyte membrane, and the membrane electrode structure is a pair of separators. What is sandwiched between is common. In the case of generating power using this fuel cell, electrochemical fuel is supplied by supplying gaseous fuel (for example, hydrogen gas) to the anode electrode of the fuel cell and supplying oxidant gas (for example, air containing oxygen) to the cathode electrode. Generate a reaction. Since only harmless water is basically generated at the time of power generation, the fuel cell is attracting attention from the viewpoint of environmental impact and utilization efficiency.

  By the way, with one fuel cell, it is difficult to obtain sufficient electric power to drive an automobile. Therefore, it is considered to form a fuel cell having a stack structure in which a plurality of cells each having a membrane electrode structure sandwiched between a pair of separators are stacked so that sufficient electric power can be supplied for driving, and mounting the fuel cell in an automobile. Has been.

In this case, it is very important to detect the voltage of the cell in order to monitor whether the cells constituting the fuel cell normally generate power. From such a viewpoint, a fuel cell having a configuration in which a cell is provided with a voltage measurement terminal has been proposed.
For example, Patent Document 1 proposes a technique in which a pair of terminals for monitoring a cell voltage are brought into contact with separators of the same polarity of adjacent cells (for example, a separator on the anode electrode side).

FIG. 5 shows a cross section of a main part of a conventional fuel cell and a voltage detection connector connected to the fuel cell. As shown in the figure, the fuel cell 30 is configured by laminating a predetermined number (in this case, n) of cells 31. Each cell 31 has a membrane electrode structure 32 sandwiched between separators 33 and 34. Each cell 31 is provided with a voltage measuring terminal 35 on a separator 33 on the anode electrode side. The cell connection device 39 is connected to the fuel cell 30 configured as described above. The cell connection device 39 is provided with a predetermined number of connectors 37, and these connectors 37 are respectively brought into contact with the terminals 35, thereby measuring the voltage of the separator 33 provided with the terminals 35, thereby obtaining the voltage of each cell. To detect.
JP 2002-352820 A

  However, there have been the following problems in the prior art. That is, in the prior art, as described with reference to FIG. 5 described above, a terminal is provided only on the separator of the same electrode (for example, the anode electrode), and the cell voltage of one cell is obtained. Monitoring across the pole separator. For this reason, when taking the last cell voltage of the laminated body which laminated | stacked the cell, since there is no next cell, the last cell voltage cannot be taken. Therefore, in order to detect the last cell voltage, as shown in FIG. 5, a cover plate (dummy separator) 40 having the same shape as a separator (anode electrode side separator) 34 to which a terminal is connected is formed in a cell laminate. It is necessary to provide the terminal 41 for the connector 42 on the cover plate 40 at the end. Thus, it is necessary to separately provide a separator, a terminal, and a connector that are not related to power generation, which increases the number of components, leading to an increase in cost, stacking width, and weight.

  Accordingly, the present invention provides a connection structure to a cell of a voltage detection connector and a fuel cell that can detect the cell voltage at both ends while suppressing the weight while suppressing the number of parts, cost, and stacking width. With the goal.

  The invention according to claim 1 is a first cell (for example, the first cell in the embodiment) having a terminal (for example, the terminal 6 in the embodiment) only on the anode (for example, the anode electrode 11 in the embodiment). 2a) is stacked from the end on the anode side, and a second cell (for example, in the embodiment) having a terminal (for example, terminal 7 in the embodiment) only on the cathode (for example, cathode electrode 12 in the embodiment) A connector (for example, connectors 8 and 9 in the embodiment) that contacts the terminal on a fuel cell (for example, fuel cell 1 in the embodiment) having a configuration in which the second cell 2b) is stacked from the cathode side end. Are connected.

  According to the present invention, since the electrodes facing each other in adjacent cells in the stacking direction have the same potential, the anode or cathode of the cell has the same potential as the cathode or anode of the cell facing this cell. It has become. Since the first cell having the terminal only on the anode is laminated from the anode side end, the potential of the anode of the first cell to be detected is the potential of the cathode of the first cell by the terminal of the anode. The electric potential is obtained from the terminal of the anode of the adjacent cell, and the voltage of the first cell to be detected can be obtained therefrom. On the other hand, since the second cell having the terminal only on the cathode is stacked from the cathode side end, the potential of the cathode of the second cell to be detected is determined by the terminal of the cathode. The potential of the anode is determined by the terminal of the cathode of the adjacent cell, and the voltage of the second cell to be detected can be determined from these. Therefore, it is possible to detect the cell voltage at both ends without separately providing dummy separators, terminals, and connectors not related to power generation at the ends. Furthermore, it can maintain high detection accuracy almost equivalent to the case where terminals are provided on the anodes or cathodes of all cells, and the total number of terminals can be reduced compared to the case where terminals are provided on the anodes or cathodes of all cells. Since it can be suppressed to approximately half, a sufficient interval between the terminals can be secured, and the connector and the terminal can be smoothly connected. In addition, an increase in weight due to the terminals can be suppressed and costs can be suppressed.

  The invention according to claim 2 is the one according to claim 1, wherein a third cell (for example, the third cell 2c in the embodiment) that does not take out a terminal from either the anode or the cathode is provided. The connector is connected to a fuel cell having a structure in which the first cells or the second cells are alternately stacked.

  According to the present invention, the fuel cell can maintain the required detection accuracy by adopting a configuration in which the third cell is alternately stacked with the first cell or the second cell. The number of terminals can be further reduced, and the weight increase and cost can be further suppressed accordingly.

  The invention according to claim 3 is a fuel cell in which a plurality of cells each having an anode and a cathode are stacked, the first cell having a terminal on each of the anode and the cathode, and the anode and the cathode among the cells. The first cell is stacked from the anode side end in the stacking direction, and the second cell is stacked from the cathode side end in the stacking direction. It is characterized by having a structure to laminate.

  According to the present invention, it is possible to detect cell voltages at both ends without separately providing dummy separators, terminals, and connectors not related to power generation at the ends. Furthermore, it can maintain high detection accuracy almost equivalent to the case where terminals are provided on the anodes or cathodes of all cells, and the total number of terminals can be reduced compared to the case where terminals are provided on the anodes or cathodes of all cells. Since it can be suppressed to approximately half, a sufficient interval between the terminals can be secured, and the connector and the terminal can be smoothly connected. In addition, an increase in weight due to the terminals can be suppressed and costs can be suppressed.

The invention according to claim 4 is the invention according to claim 3, wherein a third cell that does not take out a terminal from either the anode or the cathode is alternated with the first cell or the second cell. It comprises the structure formed by laminating.
According to the present invention, the number of terminals of the fuel cell can be further reduced while maintaining the required detection accuracy, and the increase in weight and cost can be further suppressed accordingly.

According to the first and third aspects of the invention, the cell voltage at both ends can be detected while suppressing the number of parts, the cost, and the stacking width and suppressing the weight.
According to the inventions according to claim 2 and claim 4, while maintaining the required detection accuracy, the number of terminals of the fuel cell can be further reduced, and the increase in weight and cost can be further suppressed accordingly. it can.

Hereinafter, a connection structure of a voltage detection connector to a cell and a fuel cell according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of a principal part of a cell connection device including a fuel cell and a voltage detection connector connected to the fuel cell in an embodiment of the present invention. As shown in the figure, the fuel cell 1 is configured by laminating a predetermined number (in this case, n) of cells 2. Each cell 2 has a membrane electrode structure 3 sandwiched between separators 4 and 5.

  The fuel cell 1 according to the present embodiment includes a first cell 2a (2) in which a voltage measurement terminal 6 is provided on a separator 4 on the anode electrode 11 (see FIG. 2) side, and a cathode electrode 12 (see FIG. 2). The second cell 2b (2) in which the voltage measurement terminal 7 is provided on the separator 5 on the side) and the second cell 2c (2) in which neither of the separators 4 and 5 has the terminals 6 and 7 And. The first cell 2a is disposed at the end on the + pole side, and the second cell 2b is disposed at the end on the −pole side, and the first cell 2a and The third cells 2c, the second cells 2b, and the third cells 2c are alternately stacked.

  The cell connection device 10 is connected to the fuel cell 1 configured as described above. The cell connection device 10 includes a predetermined number of connectors 8 and 9, by bringing the connector 8 into contact with the terminal 6 of the first cell 2a and the connector 9 with the terminal 7 of the second cell 2b. The potentials of the anode electrode 11 of the first cell 2a and the cathode electrode 12 of the second cell 2b can be detected.

FIG. 2 is a schematic cross-sectional view of a cell constituting the fuel cell shown in FIG. As shown in this figure, the membrane electrode structure 3 includes a solid polymer electrolyte membrane 13 and an anode electrode 11 and a cathode electrode 12 disposed on both sides thereof.
A ring-shaped seal member 14 is set on the peripheral side of the opposed surfaces of the pair of separators 4 and 5 disposed on both surfaces of the membrane electrode structure 3, and the solid polymer electrolyte membrane 13 is sandwiched by the seal member 14. To do. Both separators 4 and 5 are formed with a fuel gas passage 15, an oxidant gas passage 16, and a cooling medium passage 17 for supplying fuel gas, oxidizing gas, and cooling medium.

FIG. 3 is a plan view of the first cell and the second cell in the present embodiment. As shown in the figure, the separators 4 and 5 have fuel gas communication holes 18a and 18b, oxidant gas communication holes 19a and 19b, and cooling medium communication holes 20a and 20b formed on both sides. The left side (shown in the drawing) is the supply ports 18a, 19a, and 20a, and the other side (right side in the drawing) is the discharge ports 18b, 19b, and 20b. The separator may be formed by cutting carbon or the like, or may be formed by press molding metal or the like.
Further, the terminal 6 provided on the separator 4 of the first cell 2a and the terminal 7 provided on the separator 5 of the second cell 2b are substantially the same as seen from the stacking direction as shown in FIG. Each is formed at a position.

  In the fuel cell 1 configured as described above, a fuel gas (for example, hydrogen gas) is supplied to the anode electrode 11 through the fuel gas passage 15 and an oxidant gas (for example, oxygen) is supplied to the cathode electrode 12 through the oxidant gas passage 16. Supply air). Then, hydrogen is ionized by a catalyst layer (not shown) of the anode electrode 11 and moves to the cathode electrode 12 side through the solid polymer electrolyte membrane 13. Electrons generated during this time are taken out to an external circuit and used as direct current electric energy. At this time, hydrogen ions, electrons, and oxygen react to generate water.

  At this time, the electrodes facing each other in the cells 2a, 2c or the cells 2b, 2c adjacent in the stacking direction have the same potential. For example, the potential of the cathode electrode 12 of the first cell 2a located in the first column at the positive pole end is the same as the potential V of the anode electrode 11 of the third cell 2c in the second column adjacent to the first cell 2a. It has become. In addition, the anode electrode 11 of the second cell 2b located in the n-th column on the negative pole side has the same potential as the cathode electrode 12 of the third cell 2c located in the (n-1) -th row adjacent thereto. Yes.

  In the present embodiment, since the third cell 2c is alternately stacked with the first cell 2a or the second cell 2b, two cells (first Potential difference between one cell 2a and the third cell 2c, and between the second cell 2b and the third cell 2c). Accordingly, it is not necessary to separately provide dummy separators, terminals, and connectors that are not related to power generation, and the cell voltage at both ends can be detected while suppressing the number of parts, cost, and stacking width, and suppressing weight. .

  Since the total number of terminals 6 and 7 can be reduced to about ¼ compared to the case where the terminals 6 and 7 are provided on the anode electrode 11 or the cathode electrode 12 of all the cells 2, the terminals 6 and 7 A sufficient space can be ensured between the connectors 8 and 9 and the terminals 6 and 7 can be smoothly connected. Furthermore, the weight increase by the terminals 6 and 7 can be suppressed and the cost can be suppressed.

  Of course, the contents of the present invention are not limited to the above-described embodiments. In the embodiment, the case where the third cells are alternately stacked with the first cells or the second cells has been described. However, the number of the third cells is determined according to the required voltage detection accuracy. It can be increased or decreased. For example, the first cell and the second cell may be configured without providing the third cell. In this case, when only the first cell is stacked from one end of the fuel cell and only the second cell is stacked from the other end, all the cells are arranged by arranging cells having terminals at both the anode and cathode in the center. Can be detected. Further, the terminals 6 and 7 are formed in a protruding shape outside the end faces of the separators 4 and 5 and inserted into the connectors 8 and 9. However, the terminals are formed in a groove shape inside the end faces of the separators 4 and 5 to form a connector. The terminals may be formed integrally without changing the outer shape of the separators 4 and 5.

It is principal part sectional drawing of a cell connection apparatus provided with the fuel cell in Embodiment of this invention, and the voltage detection connector connected to this fuel cell. It is a schematic sectional drawing of the cell which comprises the fuel battery | cell shown in FIG. It is a top view of the 1st cell shown in FIG. 1, and a 2nd cell. It is a principal part perspective view of the fuel cell shown in FIG. It is principal part sectional drawing of the voltage detection connector connected to the conventional fuel cell and this fuel cell.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Fuel cell 2 (2a, 2b, 2c) ... Cell 2a ... 1st cell 2b ... 2nd cell 2c ... 3rd cell 4, 5 ... Separator 6, 7 ... Terminal 8, 9 ... Connector 10 ... Cell Connecting device 11 ... anode electrode (anode)
12 ... Cathode electrode (cathode)

Claims (4)

  A fuel cell having a configuration in which a first cell having a terminal only on the anode is laminated from the anode side end portion and a second cell having a terminal only on the cathode is laminated from the cathode side end portion is in contact with the terminal. A structure for connecting a voltage detection connector to a cell, wherein the connector is connected.   The connector is connected to a fuel cell having a configuration in which a third cell that does not take out a terminal from either the anode or the cathode is alternately laminated with the first cell or the second cell. The connection structure to the cell of the voltage detection connector of Claim 1 characterized by these. A fuel cell in which a plurality of cells having an anode and a cathode are stacked,
A first cell having a terminal on each of the anode and the cathode; and a second cell having no terminal on either the anode or the cathode of the cells;
A fuel cell comprising: a structure in which the first cell is stacked from an anode side end portion in a stacking direction, and the second cell is stacked from a cathode side end portion in a stacking direction. 4. The structure according to claim 3, comprising a structure in which a third cell that does not take out a terminal from either the anode or the cathode is alternately stacked with the first cell or the second cell. Fuel cell.

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