JP2007323815A - Fuel cell system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell system capable of replacing by a replacement part for fluid piping of a fuel cell as a single body. <P>SOLUTION: In the fuel cell system equipped with a fuel cell body 6 generating electric power by the electrochemical reaction of reaction gases; a casing 4 covering the outer periphery of the fuel cell body 6; the fluid piping 5 for the reaction gases extended from the fuel cell body 6 to the outside of the casing 4; and a through hole 7 installed in a part of the casing 4, and through which the fluid piping is passed, and in which the replacement part 11 of the fluid piping 5 is housed on the inside of the casing 4, the replacement part 11 has an extended part 8 extended to the outside of the casing 4 and is attachable and detachable together with the extended part 8. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a fuel cell system, in particular, a fuel cell main body that generates power by an electrochemical reaction of a reactive gas, a casing that covers the outer periphery of the fuel cell main body, and a reactive gas that extends from the fuel cell main body to the outside of the casing. The present invention relates to a fuel cell system including a fluid pipe for use.

  There are various types of fuel cells used in vehicles including a polymer electrolyte fuel cell (PEFC). A system using these fuel cells is basically a power generation system that generates electric power by electrochemically reacting a fuel gas (hydrogen) and an oxidizing gas (oxygen or air).

  FIG. 3 shows a schematic configuration of the fuel cell system. FIG. 3A shows a cross-sectional view of the overall configuration of the fuel cell system, and FIG. 3B shows a side view of FIG. 3A viewed from the direction AA. In this specification, the fuel cell system 1 includes a fuel cell 2, an end plate 3, a housing 4, and a fluid pipe 5. For example, in the case of a polymer electrolyte fuel cell (PEFC), the fuel cell 2 is generally joined integrally with a polymer electrolyte membrane formed of a material such as polyethylene sandwiched between gas diffusion electrodes. A plurality of single cells each composed of a MEA (Membrane Electrode Assembly) and a separator are stacked. The fuel cell 2 that is an assembly of the stacked unit cells is sandwiched between a pair of end plates 3 attached to the ends thereof and fixed by fastening bolts (not shown). In this way, a fuel cell body (stack) 6 in which the fuel cell 2 and the end plate 3 are combined is formed.

  The fuel cell main body 6 includes a supply pipe 5a for supplying a fuel gas (hydrogen), an oxidizing gas (oxygen or air), and a coolant (water, etc.), which are reaction gases, and a discharge pipe 5b for discharging to the outside. Is connected. On the other hand, the outer periphery of the fuel cell main body 6 is covered with a casing (fuel cell case) 4 together with auxiliary parts. Accordingly, the supply pipe 5 a and the discharge pipe 5 b connected to the fuel cell main body 6 pass through the through hole 7 provided in a part of the housing 4. Here, the supply pipe 5a and the discharge pipe 5b for the reaction gas are collectively referred to as a fluid pipe 5. A sealing lid 8 is provided in the through hole 7 of the housing 4 through which these fluid pipes 5 penetrate. The fluid pipe 5 is installed in the through hole 7 by the sealing lid 8.

  Further, a filter or an ion exchanger for removing impurities, dust, foreign matters and the like contained in the reaction gas is attached to the reaction gas supply pipe 5a and the discharge pipe 5b which are the fluid pipes 5 of the fuel cell 2. Since the functions of these parts such as filters and ion exchangers gradually deteriorate as a result of their use, replacement with new parts must be considered after a predetermined period. Here, filters and ion exchangers are collectively referred to as “replacement parts”. This replacement part is usually attached to a part of the fluid piping 5 together with a valve. Further, the replacement part is generally provided in the vicinity of the fuel cell main body 6 in order to use heat generated in the fuel cell main body 6 as a countermeasure against freezing in winter.

  Patent Document 1 discloses a fuel cell that prevents contact with a high voltage portion of a fuel cell main body. FIG. 4 shows a schematic cross-sectional view of the prior art relating to this fuel cell. Here, in the structure in which the power cable 38 is extended from the fuel cell main body 24 through the through hole 40 to the outside of the fuel cell case 22, a grommet (seal lid) 42 having a hole penetrating the through hole 40 is attached. Yes. Further, the power cable 38 is brought into close contact with the through hole of the grommet 42, and the grommet 42 is fitted into the through hole 40 of the fuel cell case 22. With this structure, it is possible to take out electric power and control signals from the fuel cell body 24 while protecting the fuel cell 20 having the high voltage portion 34 on the surface by the fuel cell case 22.

  Patent Document 2 discloses a fuel cell device, and discloses that a part attached to the device and requiring maintenance is disposed in the vicinity of the external panel of the package.

JP-A-2005-317408 JP 2002-216828 A

  As described above, replacement parts for fluid piping must be replaced if their function is reduced by use. However, since this replacement part is incorporated in the fuel cell main body, it is not possible to take out the single part and replace it.

  In addition, since the fuel cell main body inside the casing in which the replacement parts are stored has a high voltage portion, it is prohibited for maintenance personnel to access the fuel cell main body for maintenance. That is, the fuel cell housing cannot be opened to replace the parts. Since the residual charge amount of the fuel cell main body cannot be predicted even after the end of power generation, access to the fuel cell main body is prohibited. Therefore, in order to replace the parts, the entire housing in which the fuel cell main body is stored must be replaced.

  An object of the present application is to solve this problem and provide a fuel cell system in which replacement parts for fluid piping of a fuel cell can be safely replaced by a single component.

  In order to achieve the above object, a fuel cell system according to the present invention includes a fuel cell main body that generates power by an electrochemical reaction of a reaction gas, a casing that covers the outer periphery of the fuel cell main body, and a fuel cell main body to the outside of the casing. In a fuel cell system, comprising: an extended reaction gas fluid pipe; and a through-hole provided in a part of the casing through which the fluid pipe passes, wherein a replacement part of the fluid pipe is housed inside the casing. The replacement part has an extending part extending outside the housing and is detachable together with the extending part.

  In the fuel cell system, it is preferable that the extending portion is a sealing lid that is detachably installed on the replacement part.

  In addition, in the fuel cell system, the replacement part of the fluid piping is installed between the sealing lid and a part of the fuel cell main body, and the bolt is inserted into the bolt hole provided in the sealing lid and the replacement part. It is preferably attached to a part of the fuel cell main body.

  In addition, in the fuel cell system, the replacement part of the fluid piping is installed between the sealing lid and a part of the fuel cell main body, and a bolt is inserted into a bolt hole provided in the sealing lid. It is preferable that it is attached to a part.

  In the fuel cell system, the replacement part is preferably a filter, and the replacement part is preferably an ion exchanger.

  In the fuel cell system, it is preferable that a contact structure between the sealing lid and the replacement part is provided with a seal structure for preventing leakage of reaction gas, and the contact between the replacement part and a part of the fuel cell main body. The surface is preferably provided with a seal structure for preventing leakage of reaction gas.

  Further, in the fuel cell system, a part of the fuel cell main body is preferably an end plate.

  With the above configuration, the fuel cell system according to the present invention has the extension part that extends outside the casing, although the replacement part of the fluid pipe is provided inside the casing, and the extension part At the same time, it can be detached from the outside of the housing. Therefore, the replacement part can be taken out alone.

  Also, only replacement parts can be exchanged from outside the housing. Therefore, maintenance can be performed without replacing the entire housing in which the fuel cell main body is stored.

  Further, the replacement part can be replaced by removing it from the outside of the casing together with the extending portion. Therefore, parts can be replaced while ensuring safety without contacting the high voltage portion of the fuel cell main body.

  As described above, according to the fuel cell system of the present invention, the replacement part for the fluid piping of the fuel cell can be safely replaced by a single part.

  Embodiments according to the present invention will be described below in detail with reference to the drawings.

  FIG. 1 shows a schematic configuration of one embodiment of a fuel cell system. FIG. 1A shows a fuel cell system 1 in a sectional view, and FIG. 1B shows a side view of the fuel cell system 1 as viewed from the direction AA in FIG. In FIG. 1, as a configuration of the fuel cell system 1, a fuel cell 2, an end plate 3, a housing 4, a fuel cell main body 6, and a fluid pipe 5 are shown. Furthermore, the replacement part 11, the through-hole 7 provided in the housing 4, the sealing lid 8 that is installed in the through-hole 7 and is an extension part of the replacement part 11, the sealing lid 8, and the replacement part 11 The bolt 9 which attaches to the end plate 3 of the fuel cell main body 6 is shown. The extending part of the replacement part 11 is not limited to the sealing lid 8 of the present embodiment, and if the replacement part 11 is installed in the through hole 7, the extension part 11 is provided in a part of the replacement part 11 and outside the housing. It may be extended.

  A fuel gas (hydrogen), an oxidizing gas (oxygen or air), which is a reaction gas, and cooling water (water, etc.) are discharged to the fluid piping 5 of the fuel cell system 1 and the supply piping 5a supplied from the outside. There is a discharge pipe 5b. In the present embodiment, the fluid pipe 5 will be described as a fuel gas (hydrogen) discharge pipe 5b. In the fuel cell main body 6, hydrogen gas that is electrochemically reacted fuel gas is discharged to the outside of the housing 4 through a discharge pipe 5 b taken out from the end plate 3. At the time of this discharge, the hydrogen gas is mixed with air and reduced to a concentration that does not cause a problem even if it is discharged. However, the present fuel cell system 1 can be applied not only to the fuel gas discharge pipe 5b but also to the supply pipe 5a to which the replacement part 11 is attached or the discharge pipe 5b other than the fuel gas.

  The replacement part 11 is a filter that removes foreign matters such as impurities and dust, or an ion exchanger that removes ion-exchangeable components from the foreign matter. Moreover, the filter and the ion exchanger may be combined. In general, the replacement part 11 is installed in the vicinity of the fuel cell main body 6 in the housing 4 using heat generated in the fuel cell main body 6 in order to prevent freezing of the filter and the ion exchanger in winter. . Further, the replacement part 11 is generally integrated with a valve (not shown).

  Since the replacement part 11 removes foreign matters such as impurities and dust, its function is lowered by use. Therefore, it is necessary to consider replacement of the replacement part 11 having a reduced function with a new part at an appropriate time. The replacement part 11 is a unit with a filter and an ion exchanger incorporated therein, and the unit may be replaced. Therefore, the filter and the internal configuration of the exchange part 11 are omitted in the drawing.

  A sealing lid 8 is attached to the through hole 7 for the discharge pipe 5 b provided in the housing 4. The discharge pipe 5 b is fixed to the housing 4 by the sealing lid 8. Further, the casing 4 is secured with performance such as confidentiality by the sealing lid 8. The sealing lid 8 is provided with a plurality of bolt holes. In FIG. 1B, four bolt holes are shown, but the number is not limited to this. Further, a discharge pipe 5b outside the housing 4 is connected to the sealing lid 8 by welding. FIG. 1A shows an annular welded portion 13 between the discharge pipe 5 b and the sealing lid 8. However, this connection is not limited to welding, but may be screw-type joining. Further, the sealing lid 8 is attached to the end plate 3 of the fuel cell main body 6 via bolts 9. The bolt 9 is a one-side bolt and is screwed into a female screw hole provided in the end plate 3 in advance.

  The replacement part 11 is inserted between the sealing lid 8 and the end plate 3. The replacement part 11 is also provided with a hole through which the bolt 9 passes in advance, and the through hole 7 of the sealing lid 8, the hole of the replacement part 11, and the female screw hole of the end plate 3 are respectively tightened by the bolt 9. It is provided at a position where it can be performed.

  An annular groove 10b is formed on the surface where the sealing lid 8 and the replacement part 11 come into contact, and an O-ring is inserted to seal leakage of hydrogen as a fuel gas. Similarly, an annular groove 10a is also formed on the surface where the end plate 3 and the replacement part 11 abut, and an O-ring is inserted to seal gas leakage. In this way, the replacement part 11 is sandwiched between the sealing wall 8 and the end plate 3 and tightened with the bolts 9 so that they can be brought into close contact with each other. Sufficient sealing is possible.

  With the above configuration, the replacement part 11 can be replaced from the outside of the housing 4. The procedure will be described below. First, the bolt head 12 of the bolt 9 is loosened and removed from the outside of the housing 4. Next, the sealing lid 8 and the replacement part 11 are removed with the bolt 9 passing therethrough. The unitized replacement part 11 is replaced with a new replacement part 11, which is installed in the through hole 7 together with the sealing lid 8, and fixed to the end plate 3 with the bolt 9. By this method, the replacement part 11 can be replaced while ensuring safety without contacting the high voltage portion of the fuel cell body 6.

  The method for attaching the replacement part 11 to the end plate 3 together with the sealing lid 8 is not limited to the above-described configuration. FIG. 2 schematically illustrates another embodiment in this regard. 2A is a sectional view of the fuel cell system 1, and FIG. 2B is a side view of the fuel cell system 1 as viewed from the direction BB in FIG. 2A.

  In this embodiment, the bolt 9 is screwed directly into the female screw hole of the end plate 3 without penetrating the interior of the replacement part 11. In this case, the replacement part 11 only needs to be detachably attached to the sealing lid 8 by simple adhesion or a method of attaching a cradle for the replacement part 11 to the sealing lid 8. As a result, the replacement part 11 can be detached from the outside of the housing 4. Further, by tightening the bolt 9, the sealing surface is brought into close contact, and a sufficient sealing effect is generated. In the case of this embodiment, it is not necessary to provide bolt holes in the replacement part 11.

It is sectional drawing and the side view which show schematic structure of one Embodiment of the fuel cell system which concerns on this invention. It is sectional drawing and the side view which show schematic structure of other embodiment of the fuel cell system concerning this invention. It is sectional drawing which shows schematic structure of the whole fuel cell system. It is sectional drawing which shows schematic structure of a prior art.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Fuel cell system, 2,20 Fuel cell, 3 End plate, 4 Housing | casing, 5 Fluid piping, 5a Supply piping, 5b Discharge piping, 6,24 Fuel cell main body, 7, 40 Through-hole, 8 Sealing lid (Extension Installation part), 9 bolt, 10a, 10b annular groove, 11 replacement part, 12 bolt head, 13 welded part, 22 fuel cell case, 34 high voltage part, 38 power cable, 42 grommet.

Claims (9)

A fuel cell body that generates power by electrochemical reaction of the reaction gas, a casing that covers the outer periphery of the fuel cell body, a fluid pipe for the reaction gas that extends from the fuel cell body to the outside of the casing, and one of the casings In the fuel cell system provided with a through hole through which the fluid pipe passes, and a replacement part of the fluid pipe is housed inside the housing,
The replacement part has an extending part extending outside the casing and is detachable together with the extending part.   2. The fuel cell system according to claim 1, wherein the extending portion is a sealing lid that is detachably attached to the replacement part.   3. The fuel cell system according to claim 1, wherein the replacement part of the fluid piping is installed between the sealing lid and a part of the fuel cell main body, and is provided in the sealing lid and the replacement part. A fuel cell system, wherein a bolt is inserted into a bolt hole and attached to a part of a fuel cell main body.   3. The fuel cell system according to claim 1, wherein the replacement part of the fluid piping is installed between the sealing lid and a part of the fuel cell main body, and the bolt is provided in the bolt hole provided in the sealing lid. A fuel cell system, wherein the fuel cell system is attached to a part of the fuel cell main body.   The fuel cell system according to any one of claims 1 to 4, wherein the replacement part is a filter.   The fuel cell system according to any one of claims 1 to 5, wherein the replacement part is an ion exchanger.   7. The fuel cell system according to claim 1, wherein a sealing structure for preventing reaction gas leakage is provided on a contact surface between the sealing lid and the replacement part. Fuel cell system.   8. The fuel cell system according to claim 1, wherein a contact structure between the replacement part and a part of the fuel cell main body is provided with a seal structure for preventing reaction gas leakage. A fuel cell system.   9. The fuel cell system according to claim 1, wherein a part of the fuel cell main body is an end plate.

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