JP2006318819A - Fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To shorten as much as possible a fluid circulation route to be connected to a fuel cell. <P>SOLUTION: A fluid circulation means composed of a hydrogen circulation pump and a hydrogen circulation tube 7 connected with the pump 9 and a fluid circulation means composed of a cooled water circulation pump 31 and a cooled water intake tube 25a and a cooled water exit tube 27a both connected with the pump 31, and a fluid circulation means composed of an air humidifier unit 21 and an air supply tube 17a and an air discharge tube 23 both connected with the humidifier unit 21, are to be directly connected with a fuel cell. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fuel cell system provided with fluid circulation means for supplying a fluid such as a reaction gas or cooling water to a fuel cell, and discharging the supplied fluid to the fuel cell after discharging the supplied fluid.

  In the fuel cell system, after supplying hydrogen or air reaction gas to the fuel cell, in the case of hydrogen, the excess hydrogen discharged is circulated to be supplied to the fuel cell again for reaction, and in the case of air, the exhaust air In many cases, the moisture contained in the water is humidified in the supply air and circulated in the fuel cell.

  Similarly, the coolant for cooling the fuel cell may be provided with a circulation path (bypass path) that does not pass through the radiator, which is effective for warm-up operation of the fuel cell.

  When the fluid is circulated through the fuel cell in this way, a circulation path and a circulating device are separately connected to the fuel cell by providing piping or the like.

  By the way, when connecting by using piping as described above separately, the fluid capacity existing in the circulation path is increased by providing the piping. As a result, in the case of hydrogen or air, operability and humidification responsiveness are reduced. On the other hand, in the case of the cooling liquid, the warm-up performance deteriorates due to an increase in the liquid amount in the circulation path.

On the other hand, Patent Document 1 below describes an example in which another device is directly connected to the fuel cell.
JP 2003-217621 A

  However, what is described in Patent Document 1 described above is an example in which a fuel cell is provided with a block in which hydrogen, air, or a coolant pump is integrated and a pipe to the fuel cell is provided, and is a driving component. The pump is integrated with the fuel cell in a block, and other fluid circulation system devices and piping are not particularly considered.

  Accordingly, an object of the present invention is to shorten the circulation path of the fluid connected to the fuel cell as much as possible.

  In the present invention, fluid circulation means for supplying a fluid to a fuel cell and supplying and circulating the supplied fluid to the fuel cell again is connected directly to the fuel cell, and the fluid circulation means is connected to the fuel cell. Circulating the surplus of fuel gas supplied to the battery, circulating the moisture contained in the exhausted air after exhausting the air supplied to the fuel cell, and circulating the coolant supplied to the fuel cell The most important feature is that it is at least one of those to be made.

  According to the present invention, since the fluid circulation means for supplying the fluid supplied to the fuel cell again to the fuel cell after discharging is directly connected to the fuel cell, the fluid circulation means having a fluid circulation function for the fuel cell is provided as the fuel cell. The fluid path required for circulation can be shortened, and the number of parts, mass, manufacturing cost and assembly workability are improved.

  By shortening the fluid path required for circulation, in the case of fuel gas as the fluid, it becomes easy to change and control the pressure and flow rate, improve operability, and reduce the amount of purge gas when purging the fuel gas flow path. In the case of moisture contained in the exhaust air as a fluid, the moisture responsiveness of the moisture to the supply air is improved, and the water in the circulation path, that is, freezing at low temperatures and freezing at low temperatures should be reduced. Can do.

  Furthermore, in the case of a coolant as the fluid, not only can the pump load be reduced by reducing the coolant in the circulation path, but the temperature rise time can be increased when the temperature of the fuel cell is increased with the coolant when the fuel cell is cold. Can be shortened.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is an overall configuration diagram showing an outline of a fuel cell system according to a first embodiment of the present invention, and FIG. 2 is an arrangement diagram of components specifically showing FIG. The fuel cell 1 here is used by being mounted on a vehicle, for example, and the generated power is supplied to a motor for driving the vehicle (not shown).

  A hydrogen supply pipe 3 extending from, for example, a hydrogen tank (not shown) is connected to the hydrogen supply port 1 a of the fuel cell 1 described above, and a hydrogen pressure regulating valve 5 is provided in the hydrogen supply pipe 3. The other end of the hydrogen circulation pipe 7 that connects one end to the hydrogen discharge port 1 b of the fuel cell 1 is connected to the hydrogen supply pipe 3 downstream from the hydrogen pressure regulating valve 5.

  The hydrogen circulation pipe 7 is provided with a hydrogen circulation pump 9 to circulate surplus hydrogen discharged from the hydrogen discharge port 1b of the fuel cell 1 so as to be supplied to the fuel cell 1 again. A hydrogen discharge pipe 11 is connected to the hydrogen circulation pipe 7 between the hydrogen discharge port 1 b of the fuel cell 1 and the hydrogen circulation pump 9, and a hydrogen cutoff valve 13 is provided in the hydrogen discharge pipe 11. The hydrogen shut-off valve 13 is opened when a pressure higher than a specified level is generated, and discharges hydrogen together with air to the outside through an air discharge pipe 15 described later.

  After discharging the fluid (hydrogen) supplied to the fuel cell 1 by the hydrogen circulation pipe 7 (including the hydrogen supply pipe 3a downstream from the connecting portion between the hydrogen supply pipe 3 and the hydrogen circulation pipe 7) and the hydrogen circulation pump 9. A fluid circulation means for supplying the fuel cell 1 again is configured, and this fluid circulation means is directly connected to the fuel cell 1 without using a separate pipe.

  An air supply pipe 17 is connected to the air supply port 1 c of the fuel cell 1, and a compressor 19 is provided in the air supply pipe 17. The air pressurized by the compressor 19 is supplied to the fuel cell 1 through the air humidifier 21.

  The air humidifier 21 humidifies the air passing through the air supply pipe 17 by using moisture contained in the air discharged from the air discharge port 1d of the fuel cell 1 and flowing through the air discharge pipe 23. The used air is discharged to the outside through the air discharge pipe 15 described above. An air pressure regulating valve 24 is installed in the air discharge pipe 15.

  The above-described air discharge pipe 23, the air supply pipe 17a downstream of the air humidifier 21, and the air humidifier 21 constitute fluid circulation means for discharging the fluid (air) supplied to the fuel cell 1 and supplying it again to the fuel cell 1. The fluid circulation means is directly connected to the fuel cell 1 without using a separate pipe.

  Furthermore, one end of the cooling water inlet pipe 25 is connected to the cooling water inlet 1e of the fuel cell 1, and one end of the cooling water outlet pipe 27 is connected to the cooling water outlet 1f. The other end sides of the cooling water inlet pipe 25 and the cooling water outlet pipe 27 are connected to the radiator 29, and the cooling water is circulated by the cooling water circulation pump 31 provided in the cooling water inlet pipe 25.

  The cooling water inlet pipe 25 and the cooling water outlet pipe 27 are connected by a bypass pipe 33, and a cooling water circulation switching valve 35 is installed at a connection portion between the bypass pipe 33 and the cooling water outlet pipe 27. The cooling water circulation switching valve 35 operates so that the cooling water flows into the bypass pipe 33 by bypassing the radiator 29 when the fuel cell 1 is cold such as when the fuel cell 1 is started.

  Here, the fluid (coolant) supplied to the fuel cell 1 by the cooling water inlet pipe 25a and the cooling water outlet pipe 27a on the fuel cell 1 side from the bypass pipe 33, the cooling water circulation pump 31, and the cooling water circulation switching valve 35 is supplied. A fluid circulation means for supplying the fuel cell 1 again after discharging is configured, and this fluid circulation means is directly connected to the fuel cell 1 without using a separate pipe.

  As described above, in the first embodiment described above, the fluid circulation means for supplying the fuel cell 1 again after discharging the fluid supplied to the fuel cell 1 is directly connected to the fuel cell 1. It can be disposed close to the battery 1, the fluid path required for circulation can be shortened, and the number of parts, mass, manufacturing cost, and assembly workability are improved.

  By shortening the fluid path required for circulation, in the case of fuel gas (hydrogen) as the fluid, it is easy to change and control the pressure and flow rate, improve operability, and when purging the fuel gas flow path In the case of moisture contained in the exhaust air as a fluid, the amount of purge gas can be reduced, and the moisture responsiveness to the supply air in the air humidifier 21 can be improved by this moisture, or the water can be reduced by reducing moisture in the circulation path. Freezing at low temperatures can be reduced.

  Further, in the case of the coolant (cooling water) as the fluid, not only can the load of the coolant circulating pump 31 be reduced by reducing the coolant in the circulation path, but also the temperature rise of the fuel cell 1 is cooled when the fuel cell 1 is cooled. When using water, the heating time can be shortened.

  In the first embodiment shown in FIGS. 1 and 2, devices attached to the fuel cell 1 such as fluid circulation means may be collectively installed in the housing 37.

  FIG. 3 is a perspective view in which the fuel cell according to the second embodiment of the present invention is omitted, and a device attached to the fuel cell 1 such as a fluid circulation means instead of the housing 37 in FIGS. 1 and 2 of the fuel cell system. A housing 39 is used to accommodate the like.

  As shown in FIG. 4, which is an exploded perspective view of FIG. 3, the housing 39 is a hydrogen pressure regulating valve 5, a hydrogen circulation pump 9, a hydrogen cutoff valve 13, an air humidifier 21, and an air pressure regulating valve, which are the above-described devices. 24, receiving holes 5H, 9H, 13H, 21H, 24H, 31H, and 35H are provided for receiving the cooling water circulation pump 31 and the cooling water circulation switching valve 35, respectively.

  Here, the accommodation holes 5H, 9H and 13H of the hydrogen pressure regulating valve 5, the hydrogen circulation pump 9 and the hydrogen shut-off valve 13 are opened on the upper surface in FIG. 4, and corresponding devices are inserted through the openings on the upper surface. Deploy. Further, the accommodation holes 21H and 24H of the air humidifier 21 and the air pressure regulating valve 24 are opened in the front surface on the right side in FIG. 4, and the corresponding devices are inserted and arranged from the openings. Further, the respective housing holes 31H and 35H of the cooling water circulation pump 31 and the cooling water circulation switching valve 35 are opened on the rear surface on the left side in FIG. 4, and corresponding devices are inserted and arranged from the openings.

  The housing 39 includes the hydrogen supply pipe 3, the hydrogen circulation pipe 7, the hydrogen discharge pipe 11, the air discharge pipe 15, the air supply pipe 17, the air discharge pipe 23, the cooling water inlet pipe 25, the cooling water shown in FIG. Communication holes 3h, 7h, 11h, 15h, 17h, 23h, 25h, and 27h that serve as fluid flow paths are provided at portions in the housing 37 that correspond to the outlet pipe 27.

  And each accommodation hole which said each equipment was mentioned so that the fluid inlet / outlet part of each corresponding equipment may contact | connect and closely_contact | adhere with each of these communication holes 3h, 7h, 11h, 15h, 17h, 23h, 25h, 27h, respectively. Inserted into 5H, 9H, 13H, 21H, 24H, 31H, and 35H, respectively. At this time, although not shown, a sealing material such as an O-ring is interposed between each communication hole 3h, 7h, 11h, 15h, 17h, 23h, 25h, 27h and the corresponding devices. For example, each device after insertion has a flange formed on the outer periphery of the rear end portion in the insertion direction of each device, and the flange is fixed to the housing 39 with a bolt or the like.

  Here, the hydrogen circulation pump 9, the air humidifier 21, and the cooling water circulation pump 31 in the fluid circulation means constitute a circulation means body.

  According to the second embodiment described above, in each of the fluid circulation means, the support structure for the housing 39 and the pipes connected to each device can be omitted, so installation of the support structure and connection work of the pipes become unnecessary. The installation space and the connection work space can be omitted, and the fuel cell system as a whole can be reduced in size and improved in assembly workability.

  Here, since a plurality of fluid circulation means are arranged in one housing 39, the number of parts can be reduced compared with the case where a housing is installed for each fluid circulation means, and the entire fuel cell system can be reduced in size. And the improvement of assembly can be further enhanced.

  FIG. 5 is a perspective view showing a third embodiment of the present invention. Here, two fuel cells 1 (1A, 1B) are stacked one above the other. In this embodiment, a distribution unit that distributes each fluid to the two fuel cells 1 and supplies each fluid from the two fuel cells 1 to the housing 39 in the second embodiment shown in FIGS. A fluid manifold 41 having a collecting portion for discharging and collecting is integrated.

  That is, the fluid manifold 41 is provided with upper and lower manifolds 41A and 41B corresponding to the upper and lower fuel cells 1A and 1B, respectively, and a hydrogen outlet communicating with the hydrogen circulation pump 9 is connected to each manifold 41A and 41B. 43a and the same inlet 43b, an air outlet 45a and the same inlet 45b communicating with the air humidifier 21, a cooling water outlet 47a and an inlet 47b communicating with the cooling water circulation pump 31 and the cooling water circulation switching valve 35, respectively, are provided. Are communicated with the corresponding fluid inlets (corresponding to 1a, 1c, 1e in FIG. 1) and the fluid outlets (corresponding to 1b, 1d, 1f in FIG. 1) of the upper and lower fuel cells 1A, 1B, respectively.

  This communication can be achieved by fixing and supporting each other, for example, as shown in FIG. 6 to be described later, in a state where the housing 39 is brought into close contact with the fuel cell 1 from the state of FIG.

  In FIG. 5, the communication holes 3h, 7h, 11h, 15h, 17h, 23h, 25h, and 27h serving as the fluid flow paths shown in FIG. 3 are omitted.

  According to the third embodiment described above, since the fluid manifold 41 for fluid distribution / collection is integrated with the housing 39 that accommodates each device, even when a plurality of fuel cells 1 are provided, The number of parts can be reduced as a whole system, and the assemblability is improved.

  In the third embodiment, the housing 37 in the first embodiment shown in FIGS. 1 and 2 may be used in place of the housing 39.

  As a fourth embodiment, the above-described housings 37 and 39 are made of a resin material having at least one of the functions of heat insulation, insulation, and ion precipitation prevention.

  By providing the housings 37 and 39 with heat insulation, freezing due to temperature drop of the fluid in the flow path at low temperatures can be prevented, and by providing the housings 37 and 39 with electrical insulation, fluid can be supplied from the outside. It can be electrically insulated, and in particular, it is easy to ensure the insulation resistance of the fuel cell 1 through the cooling water, and the conductivity of the cooling water can be kept low by providing the housings 37 and 39 with an ion precipitation preventing property. It becomes easy to ensure the insulation resistance between the battery 1 and the vehicle.

  In addition, since the housing 39 is made of a resin material, the weight of the entire unit is expected to be reduced due to the light weight material, and assembling workability can be improved.

  FIG. 6 is a plan view corresponding to FIG. 2, showing a fifth embodiment of the present invention. In this embodiment, the housing 37 shown in FIG. 2 is used, and this housing 37 is fixedly supported to the fuel cell 1 by a plurality of fixing support portions 49 such as bolts and nuts (here, four locations). . In this fixed support state, the pipes 3 a, 7, 17, 23, 25 a, 27 a are in a state where they are connected to the corresponding portions of the fuel cell 1. At this time, although not shown, a sealing material such as an O-ring is interposed between the pipes 3a, 7, 17, 23, 25a, 27a and the fuel cell 1.

  Further, here, the vehicle body structures 51 and 53 extending in the longitudinal direction of the vehicle body on the left and right sides of the vehicle are connected to each other by three support members 55, 57 and 29, and the fuel cell 1 is fixed on the support members 55 and 57. At the same time, the housing 37 is fixed on the support member 59.

  According to the fifth embodiment described above, the housing 37 is fixedly supported to the fuel cell 1 by the fixing support portion 49, so that each pipe on the housing 37 side is connected to the corresponding portion of the fuel cell 1. Therefore, it is not necessary to consider the connection for each individual pipe, and therefore the number of parts can be reduced and the assemblability can be improved.

  In the fifth embodiment, the housing 39 in the second embodiment shown in FIG. 3 may be used instead of the housing 37.

  FIG. 7 is a perspective view corresponding to FIG. 3, showing a sixth embodiment of the present invention. This embodiment is different from the second embodiment of FIG. 3 in that a high voltage harness 61 as an electric wire for flowing the generated power of the fuel cell 1 and the like, and a power source and a signal for each device are flowed. A low voltage harness 63 as an electric wire is installed in an electric wire housing portion provided in the housing 39.

  FIG. 8 is an exploded perspective view showing a state in which the high voltage harness 61 and the low voltage harness 63 are removed from the housing 39 with respect to FIG. 7. The high voltage harness 61 extends in the vehicle body front-rear direction on the side surface of the housing 39. The low voltage harness 63 is installed in the upper surface grooves 39b and 39c and the front grooves 39d and 39e which are formed on the upper surface and the front surface of the housing 39, respectively. .

  The low voltage harness 63 is connected to the hydrogen pressure regulating valve 5, the hydrogen shut-off valve 13, and the sensor 64 that detects temperature and pressure, for example, installed in the communication hole 17h. Yes. The sensor 64 is also housed in a housing hole provided in the housing 39 in the same manner as each device described above.

  According to the sixth embodiment described above, the support structure of the high-voltage harness 61 and the low-voltage harness 63 can be simplified as compared with the case where these harnesses are fixedly supported by the vehicle body structural member, and is accommodated in the groove. By doing so, the extra protrusion can be eliminated and the appearance is improved.

  Further, the harnesses 61 and 63 may be installed in the housing 39. In this case, measures such as winding a protective material for protecting the harnesses 61 and 63 around are not required, and the number of equipment is reduced. It can contribute to reduction.

  In the sixth embodiment, the housing 37 in the first embodiment shown in FIGS. 1 and 2 may be used in place of the housing 39.

  FIG. 9 is a perspective view corresponding to FIG. 7, showing a seventh embodiment of the present invention. In this embodiment, plate-like protective covers 65 and 67 are installed and fixed on the outer surface of the housing 39 corresponding to the site where the high voltage harness 61 and the low voltage harness 63 are installed, as compared with the sixth embodiment of FIG. To do.

  As a result, the high voltage harness 61 and the low voltage harness 63 and the devices inside the housing can be prevented from adhering to the water mud when the vehicle is running and collision of foreign matter such as pebbles that have jumped up. In addition to the improvement in heat resistance, the heat insulation and appearance can also be improved.

  In FIG. 9, a protective cover may be appropriately provided on the front surface of the housing 39 in which the low voltage harness 63 is installed in the front grooves 39d and 39e.

  In the seventh embodiment, the housing 37 in the first embodiment shown in FIGS. 1 and 2 may be used in place of the housing 39.

  FIG. 10 is a perspective view showing an eighth embodiment of the present invention. In this embodiment, the devices attached to the fuel cell 1 such as fluid circulation means and the fuel cell 1 are accommodated in the same case 69.

  According to this, the number of parts can be reduced as compared with the case where the devices attached to the fuel cell 1 and the fuel cell 1 are housed in separate cases, and the combined volume can be reduced. The overall battery system can be made compact.

  Further, when a hydrogen leak detection system and a ventilator are provided, these can be integrated into one case 69, so that the configuration can be simplified and the number of equipment can be reduced.

  Further, since each device is housed in the same case 69 together with the fuel cell 1, the heat capacity combined with the fuel cell 1 is increased, which is advantageous for keeping the devices and the fuel cell 1 in a low temperature environment. In particular, it is possible to contribute to improving the startability of the fuel cell 1. In this case, the heat insulation can be further improved by providing the case 69 with a heat insulating structure.

  Furthermore, by accommodating each device together with the fuel cell 1 in the same case 69, measures such as damage in the event of a vehicle collision can be integrated without having to be performed separately, so parts used at that time, etc. The cost can be reduced.

1 is an overall configuration diagram showing an outline of a fuel cell system according to a first embodiment of the present invention. FIG. 2 is an arrangement diagram of each component specifically showing FIG. 1. It is the perspective view which abbreviate | omitted the fuel cell which shows the 2nd Embodiment of this invention. FIG. 4 is an exploded perspective view of FIG. 3. It is a perspective view which shows the 3rd Embodiment of this invention. FIG. 9 is a plan view corresponding to FIG. 2, showing a fifth embodiment of the present invention. It is a perspective view equivalent to the said FIG. 3 which shows the 6th Embodiment of this invention. FIG. 8 is an exploded perspective view showing a state where the high voltage harness and the low voltage harness are removed from the housing with respect to FIG. 7. It is a perspective view equivalent to FIG. 7 which shows the 7th Embodiment of this invention. It is a perspective view which shows the 8th Embodiment of this invention.

Explanation of symbols

1 Fuel cell 3h, 7h, 11h, 15h, 17h, 23h, 25h, 27h Communication hole (fluid flow path)
9 Hydrogen circulation pump (fluid circulation means, circulation means body)
7 Hydrogen circulation piping (fluid circulation means)
17a Air supply piping (fluid circulation means)
21 Air humidifier (fluid circulation means, circulation means body)
23 Air discharge piping (fluid circulation means)
25a Cooling water inlet piping (fluid circulation means)
27a Cooling water outlet piping (fluid circulation means)
31 Cooling water circulation pump (fluid circulation means, circulation means body)
35 Cooling water circulation switching valve (fluid circulation means)
37, 39 Housing 49 Housing and fuel cell fixed support 61 High voltage harness (electric wire)
63 Low-voltage harness (electric wire)
65, 67 Protective cover 69 The same case that houses the fuel cell and each device

Claims (9)

  A fluid circulation means for supplying a fluid to the fuel cell, discharging the supplied fluid and supplying the fluid to the fuel cell again for circulation is directly connected to the fuel cell, and the fluid circulation means supplies the fuel cell to the fuel cell. A circuit that circulates an excess of fuel gas, a circuit that circulates moisture contained in the exhausted air after exhausting air supplied to the fuel cell, and a circuit that circulates coolant supplied to the fuel cell. And at least one fuel cell system.   The fluid circulation means has a circulation means main body and a fluid flow path connected to the circulation means main body, and a communication hole serving as the fluid flow path is formed in a housing that accommodates the circulation means main body. 2. The fuel cell system according to claim 1, wherein the devices including the fluid circulation means are arranged in the housing so that a fluid inlet / outlet portion of the devices including the circulation means main body is in contact with the housing.   A housing for accommodating the fluid circulating means is provided, and the fluid circulating means has two systems for circulating at least two kinds of fluids, respectively, and the at least two systems of fluid circulating means are arranged in the one housing. The fuel cell system according to claim 1 or 2, wherein   A housing for accommodating the fluid circulation means is provided, and a distribution unit for distributing and supplying fluid to a plurality of fuel cells and a collecting unit for collecting fluids flowing out from the plurality of fuel cells are provided in the housing, 4. The fuel cell system according to claim 1, wherein the distribution unit and the collection unit communicate with the fluid circulation unit. 5.   2. A housing for housing the fluid circulation means is provided, and the housing is made of a resin material having at least one of a heat insulating property, an electrical insulating property, and an ion precipitation preventing property. 5. The fuel cell system according to any one of 4 above.   The housing for housing the fluid circulation means is provided, and the fluid circulation means and the fuel cell are brought into communication with each other by the fixed support of the housing and the fuel cell. The fuel cell system according to any one of 1 to 5.   The housing for accommodating the fluid circulation means is provided, and the electric wire used for the fuel cell and other devices is installed in the electric wire accommodating portion provided in the housing. The fuel cell system described in 1.   The fuel cell system according to claim 7, wherein a part of the housing where the electric wire is provided is covered with a protective cover.   2. The fuel cell system according to claim 1, wherein the fluid circulation means is accommodated in a case together with the fuel cell.

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