JP2018129166A - Fuel cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent breakage of a ventilation membrane from being delayed to damage parts inside a fuel cell case.SOLUTION: The fuel cell module includes: a fuel cell; a fuel cell case containing the fuel cell and having a through hole for ventilation; a ventilation membrane covering the through hole; and a blade portion disposed on the outer side of the ventilation membrane with a gap to the ventilation membrane and facing the ventilation membrane.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a fuel cell module.

  2. Description of the Related Art Conventionally, in a fuel cell case that accommodates a fuel cell, a configuration has been proposed in which an opening for ventilation is provided, and a ventilation membrane that prevents water from entering the opening is disposed (Patent Document 1).

Japanese Patent Laying-Open No. 2015-0776152

  In the conventional technology, when hydrogen combustion occurs in the fuel cell and the pressure in the fuel cell case increases too much, the ventilation membrane is broken by the pressure, thereby preventing an abnormal pressure increase in the fuel cell. Is done. However, in the conventional technique, a certain amount of time is required until the ventilation membrane is broken, and parts in the fuel cell case may be damaged during that time.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms.

(1) One aspect of the present invention is a fuel cell module. The fuel cell module includes: a fuel cell; a fuel cell case that houses the fuel cell and has a through hole for ventilation; a ventilation membrane that covers the through hole; And a blade portion that is disposed with a gap therebetween and that faces the ventilation membrane. According to this fuel cell module, when the pressure rises in the fuel cell case, the ventilation membrane is pressed from the inside to the outside and swells to the outside. At this time, the ventilation membrane comes into contact with the blade and the ventilation membrane is quickly broken, so that the pressure in the fuel cell case can be quickly released. Therefore, according to the fuel cell module of one aspect of the present invention, it is possible to suppress the pressure in the fuel cell case from excessively increasing and damaging the components in the fuel cell case.

It is explanatory drawing which shows the whole structure of the fuel cell module as one Embodiment of this invention. It is a top view of a ventilation cover. FIG. 3 is an end view taken along line 1-1 in FIG. 2. It is explanatory drawing which shows the detailed shape of a slat and the positional relationship of a slat and a ventilation membrane. It is an end view which shows the ventilation cover attached to the side surface of a fuel cell case. It is explanatory drawing which shows the effect of this embodiment.

  FIG. 1 is an explanatory diagram showing an overall configuration of a fuel cell module 100 as an embodiment of the present invention. The fuel cell module 100 includes a fuel cell stack 80 and a fuel cell case 10 that houses the fuel cell stack 80. The fuel cell module 100 is mounted under the floor of the vehicle.

  The fuel cell stack 80 is a cell stack in which a plurality of cells (power generation cells) of a fuel cell are stacked, for example, a solid polymer type. Each power generation cell generates power using fuel gas supplied from a fuel gas tank (not shown) mounted on the vehicle and air supplied as oxidant gas from the surroundings of the vehicle. In the present embodiment, hydrogen gas is employed as the fuel gas.

  The fuel cell case 10 has a generally rectangular parallelepiped shape, and accommodates the fuel cell stack 80 so that the longitudinal direction of the rectangular parallelepiped and the stacking direction X of the plurality of power generation cells coincide. The fuel cell case 10 is a cast product made of metal (for example, aluminum).

  The fuel cell case 10 is fixed on a stack frame (not shown) connected to the vehicle body of the vehicle. In the present embodiment, the fuel cell case 10 and the stack frame are fixed by the mount portion 12.

  Three ventilation covers 20, 30, and 40 are attached to one side surface 10 a perpendicular to the stacking direction X among the four side surfaces of the fuel cell case 10. In addition, this side surface 10a is a wall body standingly arranged so that the up-down direction Y of a vehicle may be followed. The ventilation covers 20 to 40 cover through holes for ventilation, which will be described later, formed in the fuel cell case 10.

  2 is a plan view of the ventilation cover 20, and FIG. 3 is an end view taken along line 1-1 in FIG. Since the three ventilation covers 20 to 40 have the same shape, the ventilation cover 20 that is one of them is described as a representative. As shown in both drawings, the ventilation cover 20 is an integrally molded product including a frame body 22 and a louver 24, and is made of resin. The frame 22 has a shape in which the outer shape in a plan view is roughly a triangle, and has an opening 22H having a circular cross section at the center thereof. A louver 24 is fixed to the opening 22H.

  The louver 24 is formed by assembling a plurality of slats 24a each having an elongated plate shape in parallel with a gap s therebetween. In the present embodiment, the number of slats 24a is six. In addition, as long as there are a plurality of blades 24a, any number may be used. The gap s between adjacent slats 24a is, for example, any value between 1 mm and 5 mm. The reason for setting it to 5 mm or less is to prevent intrusion of stepping stones and the like.

  The louver 24 is fixed inside the opening 22H of the frame body 22, and the angle θ of the slat 24a does not hinder the gas flow in the opening 22H and effectively prevents the entry of foreign matter. It is a suitable angle. The angle θ of the slat 24a is the size of the angle formed by the direction V of the longitudinal width (shorter width) of the slat 24a and the horizontal direction W, and is defined as a value on the side of 90 degrees or less. The In the present embodiment, the angle θ of the slat 24a is, for example, 20 to 50 degrees.

  A slit (groove) 22 </ b> S is formed at the end of the back side (the side to which the frame body 22 is attached) inside the frame body 22. The slit 22S extends along the periphery of the opening 22H and has a hollow ring shape. A ventilation membrane 50 is provided at the slit 22S so as to cover the opening 22H.

  The ventilation membrane 50 functions as a waterproof breathable membrane that allows gas permeation and prevents liquid permeation. The ventilation membrane 50 is a work cloth, a nonwoven fabric, a mesh, a net, or the like made of resin or metal. In the present embodiment, the ventilation membrane 50 is made of Teflon (registered trademark). The ventilation membrane 50 is provided with a normal ventilation capacity, and the corresponding pressure is released. In addition, the ventilation membrane 50 has strength to prevent damage from repeated cooling and vibration during use of the vehicle, vibration, and the water pressure of the submerged water. However, the ventilation membrane 50 is damaged when pressure exceeding the strength is applied. The ventilation membrane 50 is attached by welding the ventilation membrane 50 to the frame body 22 by melting the slit 22S portion of the resin frame body 22 with heat.

  FIG. 4 is an explanatory view showing the detailed shape of the slat 24a and the positional relationship between the slat 24a and the ventilation membrane 50. FIG. In the figure, the X, Y, and Z directions orthogonal to each other are defined. The X direction matches the stacking direction shown in FIG. 1, and the Z direction matches the up-down direction shown in FIG. The surface direction of the ventilation membrane 50 coincides with the direction along the YZ plane. The wing plate 24a is disposed outside the ventilation membrane 50, that is, on the side opposite to the side where the fuel cell stack 80 is accommodated. A gap of a distance d is opened between the wing plate 24a and the ventilation membrane 50.

  As described above, the slat 24a is disposed so as to be inclined by θ with respect to the horizontal direction (XY plane direction). The end surface of the wing plate 24a opposite to the ventilation membrane 50 (the side in the −X direction) has a flat shape along the YZ plane. The end surface of the wing plate 24a on the ventilation membrane 50 side (the + X direction side) has a flat shape along a plane obtained by inclining the YZ plane counterclockwise by an angle α about the Y axis. Thereby, the ventilation membrane 50 side of the slat 24a has a shape having a corner CR that faces the ventilation membrane 50 (that is, toward the + X direction side). The angle β of the corner CR is an acute angle. The angle β is, for example, 80 degrees to 30 degrees. This corner CR corresponds to a “blade”.

  FIG. 5 is an end view showing the ventilation cover 20 attached to the side surface 10 a of the fuel cell case 10. A through hole 10H having substantially the same shape and size as the opening 22H of the ventilation cover 20 is formed on the side surface 10a of the fuel cell case 10 described above. The ventilation cover 20 is attached to the side surface 10a of the fuel cell case 10 so that the through hole 10H and the opening 22H of the ventilation cover 20 are connected. This attachment is performed by inserting bolts (not shown) into the attachment holes 28 (FIG. 2) provided at three locations near the outer periphery of the ventilation cover 20 and screwing them. The attachment direction of the ventilation cover 20 is a direction in which the ventilation membrane 50 is on the through hole 10H side. In the figure, reference numeral 42 denotes a gasket. The gasket 42 enhances the sealing performance of the ventilation cover 20.

  FIG. 6 is an explanatory diagram showing the effects of the present embodiment. When hydrogen combustion occurs in the fuel cell stack 80 housed in the fuel cell case 10, the wind pressure / pressure reaches the ventilation membrane 50 through the through hole 10H, and the ventilation membrane 50 is outside, that is, the wing plate 24a. It swells when pressed to the side (-X direction side). At this time, the ventilation membrane 50 contacts the corner CR of the slat 24a as shown. As a result, the ventilation membrane 50 is broken. The distance by which the ventilation membrane 50 bulges outside is obtained in advance experimentally or by simulation, and the distance d between the gaps between the slats 24a and the ventilation membrane 50 is set shorter than the bulge distance.

  In the case of the conventional example in which the slats do not have the corner CR, the ventilation membrane has a normal ventilation capacity, and the pressure of that amount is released, so the breakage of the ventilation membrane is delayed, and the components in the fuel cell case There was a risk of damage. On the other hand, according to the fuel cell module 100 of the present embodiment, when the pressure rises in the fuel cell case 10, the ventilation membrane 50 is broken by the corner CR of the slat 24a as described above. Thus, the pressure in the fuel cell case 10 can be quickly released. Therefore, according to the fuel cell module 100 of the present embodiment, there is an effect that it is possible to suppress the pressure in the fuel cell case 10 from excessively increasing and damaging the components in the fuel cell case 10.

・ Modification 1:
In the said embodiment, it was set as the structure provided with the corner | angular part CR as a blade part in each of the six slats 24a which comprise the louver 24. FIG. Instead, the corner CR may be provided only on one or more of the six slats 24a.

Modification 2
In the said embodiment, the corner | angular part CR of the blade 24a was comprised as a blade part. Instead of this, the corners have a non-pointed shape, a conical needle part with a sharp tip is provided on the end face of the slats on the ventilation membrane side, and the ventilation membrane is broken using this needle part as a blade part. Also good.

・ Modification 3:
In the said embodiment, it was set as the structure provided with the slat 24a as a member which forms a blade part. It replaces with this and it is good also as a structure which is not provided with a slat but is provided with a blade part. Furthermore, a ventilation cover is not necessarily required, and a configuration in which a blade portion is provided in a configuration without a ventilation cover may be employed.

-Modification 4:
In the above-described embodiments and modifications, the polymer electrolyte fuel cell is used as the fuel cell. The invention may be applied.

  The present invention is not limited to the above-described embodiments and modifications, and can be realized with various configurations without departing from the spirit thereof. For example, the technical features in the embodiments and the modifications corresponding to the technical features in each embodiment described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the effects, replacement or combination can be performed as appropriate. Moreover, if the technical feature is not described as an essential thing in this specification, it is possible to delete suitably.

DESCRIPTION OF SYMBOLS 10 ... Fuel cell case 10H ... Through-hole 10a ... Side surface 12 ... Mount part 20 ... Ventilation cover 22 ... Frame body 22H ... Opening part 22S ... Slit 24 ... Louver 24a ... Blade 28 28 ... Installation hole 30, 40 ... Ventilation cover 50 ... Ventilation membrane 80 ... Fuel cell stack 100 ... Fuel cell module CR ... Square part d ... Distance

Claims (1)

A fuel cell module,
A fuel cell;
A fuel cell case containing the fuel cell and having a through hole for ventilation;
A ventilation membrane covering the through hole;
Outside the ventilation membrane, disposed with a gap with respect to the ventilation membrane, and a blade portion toward the ventilation membrane;
A fuel cell module comprising:

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