JP2020076588A - Gas leak checking device - Google Patents

Abstract

To reduce the gas leak check time by increasing a check gas charging speed.SOLUTION: A gas leak checking device (30) for a fuel battery single cell (10) comprises: a first jig (40) which is brought into contact with crests (16a) of a first separator (12) in the fuel battery single cell to form a first check space (S1) between the crests and valleys (16b); a second jig (60) which is brought into contact with crests (17a) of a second separator (13) in the fuel battery single cell to form a second check space (S2) between the crests and valleys (17b); and a gas charging unit which charges the first and second check spaces with check gas. A groove is formed in a counter face to each of separators, of each of the jigs so as to traverse contact portions between the counter face and the crests of a corrugated profile of each of the separators, and supply ports for check gas in two positions across the first check space and the second check space and a jig internal passage connecting the supply ports in two portions are formed in the first jig.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a gas leak inspection device.

  2. Description of the Related Art Conventionally, as a gas leak inspection device for a fuel cell single cell, there is known a device for inspecting the presence or absence of a gas leak from a change in gas pressure filled in the fuel cell single cell (for example, see Patent Document 1). In the gas leak inspection device described in Patent Document 1, the upper jig and the lower jig project into the upper and lower separators having a corrugated cross section of the fuel cell single cell in a state where the periphery of the fuel cell single cell is sealed with a sealing material. Applied. The inspection space between the upper jig and the valley of the upper separator and the inspection space between the lower jig and the valley of the lower separator are filled with the inspection gas, and the pressure change of the inspection gas after a predetermined time has passed. Is measured. Then, the presence or absence of gas leak in the fuel cell unit cell is inspected depending on whether the pressure change of the inspection gas is within a predetermined range.

JP, 2016-164827, A

  However, if the peaks of the upper and lower separators with a corrugated cross section are in strong contact with the upper jig and the lower jig, the flow of gas in the inspection space is obstructed at the contact points between the peaks of the separator and the jig. As a result, the filling time of the inspection gas becomes longer. Also, widen the space between the upper jig and the valley of the upper separator, and the space between the lower jig and the valley of the lower separator to prevent contact between the upper jig and lower jig and the separator. Although it is conceivable to avoid the structure, the time for filling the inspection gas becomes longer as the space is expanded.

  SUMMARY OF THE INVENTION It is an object of the present invention to provide a gas leak inspection device capable of increasing the inspection gas filling speed and shortening the gas leak inspection time.

  In order to solve the above problems, a gas leak inspection apparatus according to the present invention is an electrode assembly in which an electrode is covered with a gas diffusion layer, and is joined to one main surface of the electrode assembly to form peaks and valleys alternately. Fuel having a first separator having a corrugated section and a second separator joined to the other main surface of the electrode assembly and having a corrugated section in which peaks and valleys are alternately formed A gas leak inspection device for inspecting a gas leak of a single battery cell, wherein a first inspection space is provided between the first separator and a peak portion of a corrugated section of the first separator to form a valley between the corrugated section of the first separator. A second jig for forming a second inspection space between the first jig to be formed and the peak portion of the corrugated section of the second separator and a valley of the corrugated section. And a gas filling part for filling the first inspection space and the second inspection space with an inspection gas, and the facing surface of the first jig with respect to the first separator is the facing surface. A groove is formed so as to cross a contacting point between the surface and the peak of the corrugated section of the first separator, and the facing surface of the second jig with respect to the second separator is the facing surface. And a groove portion is formed so as to cross a contacting portion of the corrugated portion of the cross section of the second separator with each other, and at least one of the first jig and the second jig has the first The inspection gas supply ports are formed at two positions sandwiching the inspection space and the second inspection space, and the in-jig passages connecting the two supply ports are formed.

  According to the present invention, when the inspection gas is introduced into the jig during the gas leak inspection, the inspection gas flows through the in-jig passage, so that the gas is supplied at two locations sandwiching the first and second inspection spaces. Inspection gas flows from the mouth into each inspection space. Further, the inspection gas passes through the groove formed on the facing surface of the first jig with respect to the first separator and the facing surface of the second jig with respect to the second separator, so that the facing surface and each separator are separated. Even if the ridges of the ridges are in strong contact with each other, it is difficult for the contact portion to block the flow of the inspection gas. Therefore, the inspection gas filling time can be shortened by increasing the inspection gas filling speed.

It is an exploded perspective view of a fuel cell single cell concerning this embodiment. It is a figure which shows the flow of the test gas which concerns on a comparative example. It is a schematic diagram of the gas leak inspection apparatus which concerns on this embodiment. It is a bottom view of the 1st jig | tool which concerns on this embodiment. It is a top view of the 2nd jig which concerns on this embodiment. It is a figure which shows the flow of the test gas which concerns on this embodiment. It is a principal part enlarged view which shows the modification of the 1st jig | tool which concerns on this embodiment.

  Hereinafter, a gas leak inspection apparatus for a fuel cell single cell according to the present embodiment will be described with reference to the accompanying drawings. First, the fuel cell unit cell to be inspected will be described. FIG. 1 is an exploded perspective view of a fuel cell single cell of this embodiment.

  The fuel cell unit cell 10 shown in FIG. 1 constitutes one unit of a fuel cell stack, and is formed by stacking to form a fuel cell stack. The fuel cell unit cell 10 is formed in a rectangular shape in plan view by the electrode assembly 11 and the first and second separators 12 and 13 joined to both main surfaces of the electrode assembly 11. The electrode assembly 11 supports the sheet-shaped membrane electrode assembly 14 inside a rectangular frame-shaped resin frame 15. The membrane electrode assembly 14 is a so-called MEGA (Membrane Electrode & Gas diffusion layer Assembly), and includes an anode electrode on one surface of the polymer electrolyte membrane and a cathode electrode on the other surface of the polymer electrolyte membrane as a pair of gas diffusion layers. Covered with.

  The polymer electrolyte membrane of the membrane electrode assembly 14 is formed of a proton conductive ion exchange membrane formed of a solid polymer material. The anode electrode and the cathode electrode are made of, for example, a porous carbon material carrying a catalyst such as platinum. The pair of gas diffusion layers are formed of a conductive member having gas permeability, such as a carbon porous body or a metal porous body. Further, in the pair of gas diffusion layers, for example, carbon paper or carbon cloth is used as the carbon porous body, and, for example, metal mesh or foam metal is used as the metal porous body.

  The resin frame 15 is made of a thermoplastic resin such as polypropylene or polyethylene. The resin frame 15 has openings 21a and 21b for fuel gas (for example, hydrogen gas), openings 22a and 22b for oxidant gas (for example, air), and openings 23a and 23b for cooling medium (for example, cooling water). Are formed. The fuel gas openings 21a and 21b are formed at diagonal positions of the resin frame 15 with the membrane electrode assembly 14 interposed therebetween. The openings 22a and 22b for the oxidant gas are formed in the resin frame 15 at diagonal positions opposite to the openings 21a and 21b for the fuel gas, with the membrane electrode assembly 14 interposed therebetween. The openings 23a and 23b for the cooling medium are formed at positions facing the resin frame 15 with the membrane electrode assembly 14 interposed therebetween.

  The openings 21a-23a are openings for feeding the fluid into the membrane electrode assembly 14 which is a power generation region, and the openings 21b-23b are openings for delivering the fluid that has passed through the membrane electrode assembly 14. Further, the fuel gas openings 21a and 21b are formed smaller than the oxidant gas openings 22a and 22b. This is because, for example, high-purity hydrogen gas as fuel gas is fed into the membrane electrode assembly 14 through the openings 21a and 21b, and air containing low-purity oxygen as oxidant gas is fed through the openings 22a and 22b into the membrane electrode assembly. This is because it is sent to the body 14.

  The first and second separators 12 and 13 are formed by press-forming a metal plate material such as titanium, titanium alloy or stainless steel. The outer edge shape of the first separator 12 is formed in substantially the same shape as the electrode assembly 11, and like the resin frame 15, the openings 24a-26a, 24b-26b for fuel gas, oxidant gas, and cooling medium are formed. Has been done. Similarly, the outer edge shape of the second separator 13 is also formed in substantially the same shape as the electrode assembly 11, and like the resin frame 15, the openings 27a-29a, 27b- for fuel gas, oxidant gas, and cooling medium are formed. 29b is formed.

  In the central regions of the first and second separators 12 and 13, corrugated sections 16 and 17 (see FIG. 6) in which peaks 16a and 17a and valleys 16b and 17b are alternately formed are formed. The space between the ridges 16a of the first separator 12 and the membrane electrode assembly 14 is a flow path for fuel gas, and the space between the ridges 17a of the second separator 13 and the membrane electrode assembly 14 is a space. Is a flow path for the oxidant gas. In the state where a plurality of fuel cell single cells 10 are stacked, the space between the valleys 16b and 17b of the first and second separators 12 and 13 of the adjacent fuel cell single cells 10 serves as a flow path for the cooling medium. Is becoming Thus, the fuel gas and cooling medium flow paths are alternately formed on the anode side of the membrane electrode assembly 14, and the oxidant gas and cooling medium flow paths are alternately formed on the cathode side of the membrane electrode assembly 14. Has been formed.

  In the fuel cell single cell 10, the fuel gas is supplied to the flow passage defined by the first separator 12 and the membrane electrode assembly 14, and the fuel gas is oxidized by the flow passage defined by the second separator 13 and the membrane electrode assembly 14. Agent gas is supplied. The fuel gas and the oxidant gas cause an electrochemical reaction in the membrane electrode assembly 14 to generate power. At this time, the cooling medium is supplied to the flow passages defined by the first and second separators 12 and 13 of the adjacent fuel cell single cells 10. By cooling each fuel cell single cell 10 with the cooling medium, the temperature rise due to reaction heat is suppressed and the power generation performance is improved.

  In such a fuel cell unit cell 10, a gas leak test is performed on each flow path of the fuel gas, the oxidant gas, and the cooling medium. In a general gas leak inspection, the fuel cell single cell 10 is sandwiched between a pair of inspection jigs, and the inspection gas is filled in the flow path to be inspected. Then, the gas pressure in the flow path is measured in a state where the inspection gas is sealed, and the gas leak in the flow path is inspected based on the change in gas pressure after a predetermined time has elapsed. The gas leak test of the fuel gas and the oxidant gas can be filled with the test gas in an extremely short time, but the gas leak test of the cooling medium requires a long filling time of the test gas.

  More specifically, as shown in FIG. 2, the flow path of the cooling medium is between the first and second jigs 71 and 72 and the valleys 16b and 17b of the first and second separators 12 and 13. Spaces S1 and S2. The ridges 16a and 17a of the first and second separators 12 and 13 are formed flat, and the ridges 16a of the first and second separators 12 and 13 are formed by the first and second jigs 71 and 72. , 17a are contacted with metal in a wide range, that is, without a gap, and the flow of the inspection gas is obstructed at the contact position. Further, the flow of the inspection gas that has entered through the opening is partially obstructed by the sealing material 19 (see FIG. 7) provided around the opening of the fuel cell single cell 10 (first separator 12).

  As described above, in a general gas leak inspection, there are many places in the flow path of the cooling medium that obstruct the flow of the inspection gas, so that the filling speed of the inspection gas becomes slow and the inspection time becomes long. Therefore, in the gas leak inspection device 30 of the present embodiment, the first and second separators 12 and 13 with respect to the corrugated portions 16 and 17 are provided so that the flow of the inspection gas is not obstructed at the contact portion. Grooves 44 and 64 are formed in the facing surfaces 43 and 63 of the second jigs 40 and 60 (see FIGS. 4 and 5). In addition, the in-jig passage 47 is formed so that the inspection gas can be filled from the two supply ports 54 and 55 on the inlet 45 side and the outlet 46 side of the first jig 40 (see FIG. 4). .

  Hereinafter, the details of the gas leak inspection apparatus of the present embodiment will be described with reference to FIGS. 3 to 5. FIG. 3 is a schematic diagram of the gas leak inspection apparatus of this embodiment. FIG. 4 is a bottom view of the first jig of this embodiment. FIG. 5 is a top view of the second jig of this embodiment. As the inspection gas, for example, nitrogen gas is used.

  As shown in FIG. 3, the gas leak inspection device 30 has a first metal repair member that abuts the crests 16a of the first separator 12 and forms the first inspection space S1 between the crests 16b. A tool 40 and a second metal jig 60 that abuts the crest 17a of the second separator 13 and forms the second inspection space S2 between the trough 17b are provided. The first jig 40 is formed with an inlet 45 for filling the inspection gas and an outlet 46 for exhausting the gas after the gas leak inspection. The gas filling portion 31 is connected to the inspection gas inlet 45 through a pipe, and the exhaust equipment (not shown) is connected to the inspection gas outlet 46 through a pipe. A pressure sensor 32 and a valve 33 are provided in the middle of the pipe on the inlet 45 side, and a valve 34 is provided in the middle of the pipe on the outlet 46 side.

  In the gas leak inspection of the gas leak inspection device 30, in the state where the outlet 46 of the first jig 40 is sealed, the gas filling unit is operated until the gas pressure in the first and second inspection spaces S1 and S2 reaches a predetermined pressure. The inspection gas is filled into the first and second inspection spaces S1 and S2 from 31. Then, the change in gas pressure after a lapse of a predetermined time is measured by the pressure sensor 32, and the presence or absence of gas leak is inspected depending on whether the amount of change in gas pressure is within the allowable range. At this time, the filling speed of the inspection gas into the first and second inspection spaces S1 and S2 is increased by the first and second jigs 40 and 60, and the inspection time for gas leak is shortened.

  The lower surface of the first jig 40 shown in FIG. 4 is a facing surface 43 that faces the first separator 12. The outer peripheral area of the facing surface 43 is brought into contact with the sealing material 19 (see FIG. 7) of the fuel cell single cell 10, and the inner area of the facing surface 43 is brought into contact with the first separator 12. In the inner area of the facing surface 43, a plurality of groove portions 44 that avoid contact with the ridges 16a (see FIG. 6) of the first separator 12 are formed. The plurality of groove portions 44 are composed of diagonal grooves that cross obliquely and reverse diagonal grooves, and extend non-parallel to the flow channel direction formed by the first separator 12. That is, the plurality of groove portions 44 are formed so as to cross the contact portion between the facing surface 43 and the mountain portion 16 a of the first separator 12. The plurality of groove portions 44 form a flow path through which the inspection gas passes between the contact surface 43 and the crest portion 16 a of the first separator 12.

  An inlet 45 for gas filling is formed on one side surface 41 of the first jig 40 in the longitudinal direction, and an outlet 46 for gas exhaust is formed on the other side surface 42 of the first jig 40 in the longitudinal direction. There is. The first jig 40 is formed with a jig internal passage 47 that connects the inlet 45 and the outlet 46. The in-jig passage 47 is formed by connecting a horizontal hole 51 extending inward from the inlet 45 and a horizontal hole 52 extending inward from the outlet 46 with a vertical hole 53. Further, an inlet 49 of the vertical hole 53 is formed on the one lateral surface 48 of the first jig 40, but the vertical hole inlet 49 is formed so as not to connect the jig internal passage 47 to the outside through the vertical hole 53. It is sealed with a stopper (not shown).

  A pair of supply ports 54 is formed near the inlet 45 of the first jig 40 from the jig inner passage 47 to the lower surface, and near the outlet 46 of the first jig 40 from the jig inner passage 47 to the lower surface. A pair of supply ports 55 penetrating therethrough are formed. The pair of supply ports 54 are formed at positions corresponding to the openings 26a (see FIG. 1) of the fuel cell single cell 10, and the pair of supply ports 55 are located at positions corresponding to the openings 26b (see FIG. 1) of the fuel cell single cell 10. Is formed in. Thus, not only from the pair of supply ports 54 on the inlet 45 side, but also from the pair of supply ports 55 on the outlet 46 side through the jig internal passage 47, the first and second inspection spaces S1 and S2 (see FIG. 3). ) Is filled with the inspection gas.

  The upper surface of the second jig 60 shown in FIG. 5 is a facing surface 63 that faces the second separator 13. The outer peripheral area of the facing surface 63 is provided with a sealing material 65 that contacts the fuel cell single cell 10, and the inner area of the facing surface 63 contacts the second separator 13. In the inner area of the facing surface 63, a plurality of groove portions 64 are formed to avoid contact with the ridges 17a (see FIG. 6) of the second separator 13. The plurality of groove portions 64 are composed of vertical grooves and horizontal grooves that are orthogonal to each other, and extend non-parallel to the flow path direction formed by the second separator 13. That is, the plurality of groove portions 64 are formed so as to cross the contact portion between the facing surface 63 and the mountain portion 17 a of the second separator 13. The plurality of grooves 64 form a flow path through which the inspection gas passes between the contact surface 63 and the crest 17a of the second separator 13.

  The flow of the inspection gas in the first and second jigs and the fuel cell unit cell will be described with reference to FIG. FIG. 6 is a diagram showing the flow of the inspection gas according to the present embodiment.

  As shown in FIG. 6, when the inspection gas is filled from the inlet 45 side of the first jig 40, a portion of the inspection gas is supplied to the fuel cell unit cell 10 from a pair of supply ports 54 near the inlet 45. It flows into one end. The inspection gas that has passed through the pair of supply ports 54 flows into the first inspection space S1 between the first jig 40 and the valley portion 16b of the first separator 12, and at the same time, the opening of the fuel cell unit cell 10 is opened. Through to the second inspection space S2 between the second jig 60 and the valley portion 17b of the second separator 13. As a result, the inspection gas is filled into the first and second inspection spaces S1 and S2 from one end side of the fuel cell single cell 10 through the pair of supply ports 54 in front of the in-jig passage 47.

  On the other hand, the inspection gas passing through the pair of supply ports 54 flows through the jig internal passage 47 toward the outlet 46 side, and a part of the inspection gas is supplied from the pair of supply ports 55 near the outlet 46 to the fuel cell single cell. It flows into the other end side of 10. The inspection gas that has passed through the pair of supply ports 55 flows into the first inspection space S1 between the first jig 40 and the valley portion 16b of the first separator 12, and at the same time, the opening of the fuel cell unit cell 10 is opened. Through to the second inspection space S2 between the second jig 60 and the valley portion 17b of the second separator 13. As a result, the inspection gas is filled into the first and second inspection spaces S1 and S2 from the other end side of the fuel cell single cell 10 through the pair of supply ports 55 on the inner side of the in-jig passage 47.

  Further, although the facing surface 43 of the first jig 40 strongly abuts the ridges 16a of the first separator 12, the inspection gas passes through the groove 44 formed in the facing surface 43, so that There is no strong obstruction to the flow of the inspection gas at the contact point. In this way, the inspection gas flows into the first inspection space S1 from the inlet 45 side and the outlet 46 side of the first jig 40, and the inspection gas is passed through the groove portion 44 of the facing surface 43 to the inspection gas. By passing, the inspection gas is quickly spread to the first inspection space S1. Therefore, the filling time of the inspection gas into the first inspection space S1 can be shortened.

  Similarly, the facing surface 63 of the second jig 60 strongly abuts the crest 17a of the second separator 13, but the inspection gas passes through the groove 64 formed in the facing surface 63, The flow of the inspection gas is not strongly obstructed at the contact point. In this way, the inspection gas flows from the inlet 45 side and the outlet 46 side of the first jig 40 into the second inspection space S2, and the inspection gas is passed through the groove portion 64 of the facing surface 63 to the inspection gas. By passing, the inspection gas is quickly spread to the second inspection space S2. Therefore, the filling time of the inspection gas into the second inspection space S2 can be shortened.

  In the present embodiment, the pair of supply ports 54 on the inlet 45 side of the first jig 40 shown by the dotted line in FIG. 7 are formed at positions corresponding to the openings of the fuel cell single cell 10. Therefore, the sealing material 19 around the opening of the fuel cell unit cell 10 partially blocks the flow of the inspection gas that has entered through the pair of supply ports 54. In this case, in addition to the pair of supply ports 54, the supply port 57 may be formed at a position deviated from the opening of the fuel cell single cell 10. As a result, the flow of the inspection gas that has entered through the supply port 57 is not obstructed by the sealing material 19. Similarly, a supply port (not shown) may be formed on the outlet 46 side of the first jig 40 at a position outside the opening of the fuel cell single cell 10.

  As described above, in the gas leak inspection apparatus 30 of the present embodiment, when the inspection gas is introduced into the jig during the gas leak inspection, the inspection gas flows through the in-jig passage 47. The inspection gas flows into the inspection spaces S1 and S2 from the two supply ports 54 and 55 sandwiching the inspection spaces S1 and S2. Further, the inspection gas passes through the groove portions 44 and 64 formed in the facing surface 43 of the first jig 40 facing the first separator 12 and the facing surface 63 of the second jig 60 facing the second separator 13. .. Therefore, even if the facing surfaces 43 and 63 and the peaks 16a and 17a of the separators 12 and 13 are in strong contact with each other, the flow of the inspection gas is less likely to be hindered by the contact points. Therefore, the inspection gas filling time can be shortened by increasing the inspection gas filling speed.

  Further, in the present embodiment, the inlet 45 and the outlet 46 are formed in the first jig 40, but the inlet 45 and the outlet 46 may be formed in the second jig 60. The entrance 45 and the exit 46 may be formed in both the jigs 40 and 60 of the second jig. Therefore, the jig internal passage 47 may be formed in the second jig 60, or the jig internal passage 47 may be formed in both the first and second jigs 40 and 60.

  Further, in the present embodiment, the supply port 54 is formed near the inlet, the supply port 55 is formed near the outlet, and the jig passage 47 is formed so as to connect the supply ports 54 and 55, but the configuration is not limited to this. The supply ports 54 and 55 are formed at two locations sandwiching the first and second inspection spaces S1 and S2, and if the jig internal passage 47 is formed so as to connect the supply ports 54 and 55 at the two locations. Good.

  Further, although the present embodiment has been described, another embodiment may be a combination of the embodiment and the modification in whole or in part. Furthermore, the technology of the present disclosure is not limited to the present embodiment, and may be variously changed, replaced, and modified without departing from the spirit of the technical idea. Further, if the technical idea can be realized in another way by the advancement of the technology or another derivative technology, the method may be implemented using the method. Therefore, the claims cover all embodiments that may be included within the scope of the technical idea.

10: Fuel cell single cell, 11: Electrode assembly, 12: First separator, 13: Second separator, 14: Membrane electrode assembly, 30: Gas leak inspection device, 31: Gas filling part, 40: First Jig, 43: facing surface, 44: groove part, 47: passage in jig, 54: supply port, 55: supply port, 57: supply port, 60: second jig, 63: facing surface, 64: groove part , S1: first inspection space, S2: second inspection space

Claims (1)

An electrode assembly that covers the electrode with a gas diffusion layer; A gas leak inspection apparatus for inspecting a gas leak of a fuel cell single cell, which is joined to the other main surface and includes a second separator having a corrugated section in which peaks and valleys are alternately formed,
A first jig that abuts on a crest of the corrugated section of the first separator to form a first inspection space between the trough and the corrugated section of the first separator;
A second jig that abuts on a peak of the corrugated section of the second separator and forms a second inspection space between the peak and the trough of the corrugated section;
A gas filling unit that fills the first inspection space and the second inspection space with an inspection gas;
On the facing surface of the first jig with respect to the first separator, a groove portion is formed so as to cross the contact portion between the facing surface and the mountain portion of the corrugated section of the first separator,
A groove portion is formed on the facing surface of the second jig with respect to the second separator so as to cross the contact portion between the facing surface and the mountain portion of the corrugated section of the second separator.
At least one of the first jig and the second jig is provided with an inspection gas supply port at two positions sandwiching the first inspection space and the second inspection space, A gas leak inspecting device, wherein a jig internal passage connecting the two supply ports is formed.

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