JP2008293811A - Gas supply member of fuel cell, and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress, with a simple means, discharge of moisture by gas flow in a porous body forming a gas passage to a fuel cell electrode. <P>SOLUTION: The gas supply member 30 is formed of a porous body and circulates a reaction gas (hydrogen gas, air) supplied from a supply port 41i of a separator 40 toward a discharge port 41o, and diffuses throughout the all surfaces of a gas diffusion member 22 to deliver to it. Then, the gas supply member 30 includes a plurality of lines of cut-out grooves 31 crossing the flow of the gas going from the supply port 41i to the discharge port 41o of gas, and by these cut-out grooves 31, connection of the holes of the gas supply member 30 being the porous body is cut by crossing the gas flow. Thereby, when the gas passes through the cut-out grooves 31, moisture which is being discharged with the gas, is retained in these cut-out grooves 31. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a porous gas supply member that supplies a reaction gas while diffusing it to electrodes of a membrane electrode assembly in which electrodes are bonded to both sides of an electrolyte membrane, and a fuel cell using the porous gas supply member.

  The fuel cell includes a fuel cell having a membrane electrode assembly as a power generation unit, and diffuses and supplies a reaction gas to each electrode of the membrane electrode assembly by a gas supply member. For such a gas supply member, a porous body is frequently used, and pores of the porous body are used as gas flow paths (for example, Patent Document 1).

JP 2006-49105 A JP 2006-134582 A JP 2005-294119 A JP-A-8-138696 Japanese Patent Laid-Open No. 5-251097

  In these patent documents, various proposals have been made in order to ensure mechanical strength when using a porous body, improve drainage of generated water accompanying an electrode reaction, and the like. For example, a member for supplying gas to the porous body is used to ensure the strength, the porous body is formed wide and narrow along the gas flow, or the shape of the gas supply flow path to the porous body By devising, etc., the drainage of generated water is improved.

  By the way, in the porous body, the gas flows from the gas supply side to the discharge side. Therefore, it is a problem to take out the moisture of the porous body by this gas, for example, the generated water or the reaction gas from the water vapor component in the gas. It came to be. Since the polymer electrolyte membrane exhibits proton conductivity in a wet state, excessive moisture removal due to gas in the porous body may result in drying of the porous body and, consequently, a decrease in the wetness of the electrolyte membrane. Because there is no, there is a concern that the power generation capacity will decline. In this case, when the drainage of the generated water is enhanced as proposed in the above-mentioned patent document, the adverse effects due to the above-described method of taking out the water become remarkable.

  The present invention is made in order to solve the above-mentioned problems when a gas flow path to an electrode in a fuel cell is formed of a porous body, and is a simple method for suppressing moisture removal due to a gas flow in the porous body The purpose is to provide.

  In order to achieve at least a part of the above object, the present invention adopts the following configuration.

[Application: Gas supply components]
A gas supply member for supplying a reaction gas while diffusing the reaction gas to the electrode in a membrane electrode assembly having an electrolyte membrane and electrodes joined to both sides of the electrolyte membrane,
Formed from a porous body, and the connection of the pores of the porous body as a gas flow path,
The gist of the present invention is to include a hole dividing section that divides the connection of the holes by crossing the flow of the reaction gas from the reaction gas supply side to the discharge side.

  In the gas supply member described above, when the reaction gas is supplied while diffusing to the electrode in the membrane electrode assembly, the porous body, which is a constituent material, is provided with a hole dividing portion, and this hole dividing portion allows the gas in the porous body. The connection of the holes forming the flow path is divided by intersecting the flow (gas flow) of the reaction gas from the supply side toward the discharge side. Therefore, when the reaction gas flows downstream along the gas flow from the supply side to the discharge side, the reaction gas passes through the hole dividing part and flows downstream from the hole dividing part. For this reason, when the reaction gas flowing along the gas flow tries to flow moisture downstream of the gas flow, when the reaction gas passes through the hole dividing portion, the water stays in the hole dividing portion and retains water. Will be. As a result, it is possible to easily prevent moisture from being taken out by the reaction gas in the porous body by a simple method of providing a pore dividing portion in the porous body.

  The gas supply member described above can be configured as follows. For example, when providing the hole dividing portion, the hole dividing portion is installed from the supply side to the discharge side so that the connection dividing area by the hole dividing portion becomes wider toward the supply side. Can do. This has the following advantages.

  When the reaction gas flows from the supply side to the discharge side in the porous body, the reaction components (hydrogen and oxygen) of the reaction gas reach the membrane electrode assembly and are consumed for the electrochemical reaction. Therefore, a difference occurs in the gas flow rate from the supply side to the discharge side, and the gas flow rate is smaller on the discharge side than on the supply side. For this reason, it is expected that excessive supply of moisture by the reaction gas tends to occur on the supply side where the gas flow rate is large. However, as described above, if the hole dividing portion is installed from the supply side to the discharge side so that the connection dividing region by the hole dividing portion becomes wider toward the supply side, the moisture is excessively taken out. However, on the supply side where the connection is expected, since the connection dividing region by the hole dividing part is wide, the effectiveness of water retention at the hole dividing part is increased accordingly. Therefore, even on the supply side where excess moisture is expected to be taken out, moisture removal due to gas can be more reliably and easily suppressed.

  In this case, the hole dividing portion can be a groove intersecting with the flow of the reaction gas, and thus the hole dividing portion can be easily formed. And when making a hole parting part into a groove | channel, it can also be set as not only a linear groove | channel but a wavy groove | channel. In the case of a wavy groove, the interference range between the reaction gas flowing along the gas flow from the supply side to the discharge side and the groove is widened, so the effectiveness of water retention at the hole dividing portion (the wavy groove) is further increased. In addition, the effect of suppressing moisture removal is increased. In addition, although the groove | channel as a hole parting part can be made into a continuous groove | channel, or it can also be made into the connection (dotted) of the groove | channel divided into plurality, If it makes it a continuous groove | channel, the formation will become easy. Further, the groove as the hole dividing portion can be formed so that the groove width is wider toward the supply side, and the number of grooves is larger toward the supply side. In this way, the hole dividing portion (groove) can be easily made dense by hanging from the supply side to the discharge side.

  Furthermore, if the groove as the hole dividing portion is a bottomed groove, one surface of the porous body can be a flat surface. Therefore, the porous body is brought into contact with the electrode of the membrane electrode assembly or another gas permeable member (for example, a gas diffusion layer or a gas diffusion member) interposed between the electrode and the porous body. Since the reaction gas can be uniformly diffused and supplied over almost the entire surface of the electrode while ensuring the contact with the surface of the body, it is also preferable for power generation in the membrane electrode assembly.

  Moreover, a hole parting part can also be formed in the said porous body as a hollow part, and can also be formed as a through-hole which penetrates the said porous body. Even in the case of such a hole dividing portion, it is possible to easily suppress moisture removal by the above-described water retention.

  The gas supply member described above can also be applied as a fuel cell using the gas supply member. That is, this fuel cell includes a fuel cell having a membrane electrode assembly having an electrolyte membrane and electrodes joined to both sides of the electrolyte membrane as a power generation unit, and a gas supply member for supplying a reaction gas while diffusing the reaction gas to the electrode The gas supply member is any one of the gas supply members described above.

  Hereinafter, embodiments of the present invention will be described based on examples. FIG. 1 is an explanatory view schematically showing in cross section the configuration of a fuel cell 10 constituting a fuel cell as an embodiment of the present invention, and FIG. 2 is a schematic configuration of a gas supply member 30 constituting the fuel cell 10. It is a perspective view shown.

  As shown in the figure, the fuel cell 10 includes a membrane electrode assembly (MEA) 20 in which electrodes are bonded to both surfaces of an electrolyte membrane having proton conductivity, and one electrode is used as an anode and the other is used as an anode. The MEA 20 is used as a power generation unit using the electrode as a cathode. Various electrolyte membranes of the MEA 20 can be adopted, and can be a solid polymer membrane or an electrolyte membrane using a solid oxide or the like as an electrolyte.

  Further, the fuel battery cell 10 has a gas diffusion member 22 and a gas supply member 30 on each electrode surface side of the MEA 20 in order to diffusely supply a reactive gas (hydrogen gas for an anode and oxygen for a cathode). Is provided. The gas diffusion member 22 is joined to both electrodes of the MEA 20 and delivered while diffusing the reaction gas to the electrodes. The gas supply member 30 is a porous body formed of a porous material such as a metal mesh or carbon paper, and the reaction gas supplied via the separator 40 is gasified using a hole connection in the porous body as a gas flow path. Supply to the diffusing member 22. Although it is porous even in the gas diffusion member 22, the gas diffusion member 22 has finer pores than the gas supply member 30 in order to diffuse gas to the electrode surface. In this case, the gas diffusion member 22 and the gas supply member 30 may be configured as a single unit so that gas can be supplied to the electrodes by diffusion.

  The gas supply member 30 is formed in a rectangular shape from a porous body as described above, and includes a V-shaped bottomed cutout groove 31 on the separator 40 side. As shown in FIG. 2, the notch groove 31 is formed in a plurality of lines by cutting or the like. The manner in which the cutout groove 31 is formed will be described later.

  A plurality of the above-described fuel cells 10 are sandwiched between the separators 40 on both sides to constitute a fuel cell. That is, the fuel cell has a stack structure in which a plurality of fuel cells 10 are stacked with the separators 40 interposed therebetween. In this case, the number of stacked fuel cells 10 in the fuel cell can be arbitrarily set according to the output required for the fuel cell. Further, the fuel cell 10 is sealed around the cell by a seal gasket 24 made of, for example, silicon rubber, and this seal gasket 24 is used to react gas (hydrogen gas / air) to each stacked fuel cell. ) And cooling water (not shown) are formed in cooperation with the separator 40.

  The separators 40 on both sides of the fuel battery cell 10 not only separate the fuel battery cell 10 but also participate in the reaction gas supply from one end of the cell to the other end and the cooling water circulation. That is, the separator 40 includes a gas supply port 41i at one of the upper and lower ends in the figure, and a gas discharge port 41o at the other end. In the fuel cell 10 shown in FIG. 1, the separator 40 on the left side in the drawing supplies air from the supply port 41 i and discharges air from the discharge port 41 o. The right separator 40 supplies hydrogen gas from the supply port 41i and discharges excess hydrogen gas from the discharge port 41o. Therefore, the fuel cell 10 in FIG. 1 is a fuel cell in which the left electrode of the MEA 20 is a cathode and the right side is an anode, and the air supplied from the lower supply port 41i in the figure is The gas is supplied to the cathode of the MEA 20 via the gas supply member 30 and the gas diffusion member 22, and excess air is discharged from an upper discharge port 41o in the drawing. Further, the hydrogen gas supplied from the upper supply port 41i in the figure is supplied to the anode of the MEA 20 via the gas supply member 30 and the gas diffusion member 22, and the surplus hydrogen gas is on the upper side in the figure. It discharges from the discharge port 41o. The surplus air and hydrogen gas are supplied to the adjacent fuel cell 10 via the seal gasket 24 between the separators.

  The fuel cell having the stack structure described above is fastened by a fastening member (not shown) in the stacking direction of the fuel cells 10 and a fastening load is applied in the cell stacking direction. With this fastening load, suppression of cell performance degradation due to an increase in contact resistance at any location of the stack structure and prevention of leakage of gas and cooling water flowing inside the fuel cell are achieved.

  Next, how the notch groove 31 is formed in the gas supply member 30 will be described. The gas supply member 30 is located between the separator 40 and the gas diffusion member 22 and receives supply of reaction gas (hydrogen gas / air) from the supply port 41 i of the separator 40. For example, the gas supply member 30 on the cathode side on the left side in FIG. 1 is a porous body and has a hole flow path as described above, and therefore is supplied from the supply port 41i on the lower end side in FIG. The received air flows from the lower side to the upper discharge port 41o in the drawing and is delivered to the gas diffusion member 22 while being diffused over the entire surface. Similarly, in the gas supply member 30 on the anode side on the right side of FIG.

  The air flow from the supply port 41i to the discharge port 41o in FIG. 1 is shown as a gas flow in FIG. 2, and the gas supply member 30 includes a notch groove 31 having the following relationship with this gas flow. That is, when the gas supply member 30 forms the cutout grooves 31 having a plurality of lines, the gas supply members 30 form the respective cutout grooves 31 so as to intersect the gas flow of FIG. 2 from the air supply port 41i to the discharge port 41o in FIG. . Since each of the cutout grooves 31 is a cutout of the gas supply member 30, the connection of the holes of the gas supply member 30, which is a porous body, is cut across the gas flow shown in FIG. Therefore, this notch groove 31 corresponds to the hole dividing portion in the present invention.

  The cathode-side gas supply member 30 includes the cutout grooves 31 closer to the air supply port 41i in FIG. 1 and closer to the discharge port 41o. More specifically, the cutout grooves 31 are formed at a narrow pitch at the air supply port 41i (see FIG. 1), and at a wider pitch toward the discharge port 41o (see FIG. 1). . Therefore, the gas supply member 30 is provided with the cutout grooves 31 densely from the supply port 41i to the discharge port 41o so that the cut-off region of the hole connection by the cutout groove 31 is as wide as the supply port 41i. The same applies to the gas supply member 30 on the anode side.

  In the fuel cell 10 having the gas supply member 30 described above, when supplying air while diffusing air to the electrode (anode electrode) of the MEA 20 via the gas supply member 30 on the cathode side, the porous gas supply member 30 is provided. The plurality of cutout grooves 31 formed in the cross section divide the connection of the holes forming the gas flow path in the porous body so as to intersect the gas flow of FIG. 2 from the supply port 41i toward the discharge port 41o. Thus, even if the cutout groove 31 exists in the gas supply member 30, when the air flows downstream through the gas supply member 30 along the gas flow of FIG. 2 from the supply port 41i to the discharge port 41o, It passes through the notch groove 31 and flows downstream from the groove. The air flowing along this gas flow tries to flow downstream by putting moisture existing in the holes of the gas supply member 30 or moisture in the air on the gas flow. However, when the air passes through the respective cutout grooves 31, since the connection of the holes is cut off in the cutout grooves 31, the water remains in the cutout grooves 31 and is retained. As a result, moisture removal due to air in the porous body can be easily suppressed by a simple method of providing a plurality of notched grooves 31 in the gas supply member 30 formed of the porous body. The same applies to the gas supply member 30 on the anode side. For this reason, in MEA20, since the situation which becomes insufficiently wet insufficient does not occur, it becomes possible to maintain the power generation capacity.

  In this embodiment, when the gas supply member 30 is provided with the plurality of cutout grooves 31, the cutout grooves 31 are provided at a narrow pitch on the supply port 41i side and at a wide pitch on the discharge port 41o side. The groove 31 was made dense by hanging from the supply port 41i side to the discharge port 41o side. For this reason, since the dividing area | region of the hole connection of the porous body by the notch groove | channel 31 of the several streaks in the gas supply member 30 becomes large toward the supply port 41i side, there exists the following advantage.

  In the porous gas supply member 30, when air flows from the supply port 41 i side to the discharge port 41 o side in FIG. 1, oxygen in the air passes through the gas diffusion member 22 and the electrode (cathode) of the MEA 22. It reaches the electrode) and is consumed in the electrochemical reaction. Therefore, a difference occurs in the air flow rate from the supply port 41i side to the discharge port 41o side, and the air flow rate is smaller on the discharge port 41o side than on the supply port 41i side. For this reason, it is expected that excessive moisture removal due to the air flow tends to occur on the supply port 41i side where the flow rate is large. However, on the side of the supply port 41i where excess moisture is expected to be taken out, the dividing region of the hole connection by the notch groove 31 is widened, so that the effectiveness of water retention in the notch groove 31 is increased accordingly. Therefore, moisture removal due to air can be more reliably and easily suppressed even on the supply port 41i side where excessive moisture removal is expected. The same applies to the gas supply member 30 on the anode side.

  In this embodiment, it is simple because a plurality of notched grooves 31 need only be formed in a straight line so as to intersect the gas flow shown in FIG. In addition, since the bottomed notch groove 31 is formed on the separator 40 side, the gas supply member 30 can be joined to the gas diffusion member 22 in a plane so as to ensure surface contact. Therefore, since air and hydrogen gas can be diffused and supplied to the respective electrodes of the MEA 20 over almost the entire surface, it is preferable for power generation in the MEA 20.

  Next, other embodiments and modifications will be described sequentially. FIG. 3 is a perspective view showing a schematic configuration of a gas supply member 30A according to a modification. As shown in the drawing, the gas supply member 30A includes a rectangular cutout groove 31A instead of the V-shaped groove. That is, various groove shapes of the notch grooves can be adopted. FIG. 4 is a perspective view showing a schematic configuration of a gas supply member 30B of another modified example. As shown in the figure, the gas supply member 30B includes a plurality of notched grooves 31B having different groove widths and formation pitches. In other words, the notch groove 31B is wide on the supply port 41i side in FIG. 1, and the groove width is narrower toward the discharge port 41o side, and the groove pitch is wider. FIG. 5 is an explanatory view showing a schematic configuration of a gas supply member 30C according to another modification in a plane and a side. As shown in the figure, the gas supply member 30C includes a wave-shaped bottomed cutout groove 31C instead of the straight cutout groove 31, and each cutout groove 31C intersects the gas flow. In other words, the groove trajectory of the notch groove is not limited to a linear shape, and various types such as a wave shape can be adopted. Even with the gas supply members 30 </ b> A and 30 </ b> B of these modified examples, the above-described effects can be achieved. In particular, in the notch groove 31C shown in FIG. 5, since the notch groove 31C is a wave-like groove, the interference range between the reaction gas and the groove flowing along the gas flow shown from the gas supply side to the discharge side is widened. Therefore, the water retention effectiveness in the wave-shaped notch groove 31C is further enhanced, and the effect of suppressing moisture removal is also increased, which is preferable.

  FIG. 6 is an explanatory diagram showing a schematic configuration of a gas supply member 30D according to a modification of the aspect in which the cutout groove is divided. As shown in the figure, the gas supply member 30D includes bottomed cutout grooves 31D arranged in a straight line and has a plurality of rows. That is, the cutout groove can be a continuous groove or a divided groove. In the gas supply member 30D, the cutout grooves 31D in the adjacent rows are provided in a so-called staggered manner, so that the reaction gas can always pass through the cutout grooves 31D when flowing along the gas flow shown in the figure. Even in this modification, the effects described above can be achieved.

  FIG. 7 is an explanatory view showing a schematic configuration of a gas supply member 30E of another modified example in a plan view and a side view in which the main part is broken, and FIG. 8 is a plan view of the schematic configuration of the modified example of the gas supply member 30E in FIG. It is explanatory drawing shown by the side view which fractured | ruptured the view and the principal part. The gas supply member of these modified examples has a through-hole penetrating the gas supply member in the thickness direction, instead of the bottomed cutout groove.

  The gas supply member 30E in FIG. 7 includes a plurality of rectangular through holes 31E penetrating in the thickness direction, and the through holes 31E are formed in the same manner as the formation pitch of the cutout grooves 31 in the gas supply member 30. A narrower pitch is formed toward the supply port 41i. Since the gas supply member 30 is joined to the gas diffusion member 22 as shown in FIG. 1, it functions as a groove whose one end is closed by the gas diffusion member 22 even in the through long hole 31E. Similarly to the notch groove 31, the hole connection of the gas supply member 30E, which is a porous body, is divided so as to intersect the gas flow shown in the figure. Accordingly, the through long hole 31E corresponds to the hole dividing portion in the present invention. The gas supply member 30F shown in FIG. 8 includes through holes 31F arranged in a straight line in multiple rows, and the through holes 31F in adjacent rows are arranged in a so-called staggered pattern. FIG. 9 is an explanatory view showing a schematic configuration of a modified example in which the gas supply member 30F shown in FIG. The gas supply member 30G shown in FIG. 9 includes through long holes 31G having a shape obtained by dividing the long through holes 31F in a multi-row and zigzag manner. Even in these modifications, the effects described above can be achieved.

  FIG. 10 is an explanatory view showing a schematic configuration of another modified example of the gas supply member having a through hole in a plan view and a side view in which a main part is broken. The illustrated gas supply member 30H has through holes 31H penetrating in the thickness direction arranged in a straight line and provided in multiple rows, and the through holes 31H in adjacent rows are arranged in a so-called staggered pattern. Even in the through hole 31H, it functions as a groove whose one end is closed by the gas diffusion member 22, so that, similarly to the notch groove 31, a gas flow illustrating the connection of the holes of the gas supply member 30H as a porous body. Cross over and divide. Therefore, even if it exists in this through-hole 31H, it is corresponded to the hole parting part in this invention. And even if it is this modification, there can exist the effect mentioned above.

  Next, another modification will be described. This modification is characterized by the formation of a through hole that penetrates the gas supply member. FIG. 11 is an explanatory view schematically showing the configuration of a fuel cell 100 according to another modification that constitutes the fuel cell, and FIG. 12 is a perspective view schematically showing the configuration of a gas supply member 130 that constitutes the fuel cell 100. FIG. As shown in the figure, even in the fuel cell 100, the gas diffusion member 22 and the gas supply member 130 are joined to both sides of the MEA 20 and are sandwiched by the separator 40. The gas supply member 130 is a rectangular porous body like the gas supply member 30 described above, and includes a plurality of rows of through-holes 131 along the side of the rectangle as shown in FIGS. 11 and 12. . The through holes 131 are formed at a narrow pitch on the side of the reaction gas (air or hydrogen gas) supply port 41i in FIG. It is formed with a wider pitch toward the.

  Since this through hole 131 intersects the gas flow of FIG. 2 from the reaction gas (air or hydrogen gas) supply port 41i to the discharge port 41o in FIG. 1, the hole of the gas supply member 130, which is a porous body, is formed. Is cut across the gas flow shown in FIG. Therefore, since the through hole 131 corresponds to the hole dividing portion in the present invention and the hollow portion which is one form thereof, the gas supply member 130 having the through hole 131 also has the effects described above. Can do.

  In order to obtain the gas supply member 130 having the through hole 131 penetrating along the rectangular side, the following may be performed. As shown in FIG. 12, the gas supply member 130 is divided into an upper part 131u and a lower part 131d, and a semicircular groove in which the through hole 131 is divided is formed on the joint surface of both parts. Then, the gas supply member 130 can be obtained by joining the upper and lower parts.

  FIG. 13 is an explanatory view showing a modification of the gas supply member having a through hole 131A along a rectangular side. As shown in the figure, the gas supply member 130A of this modification has a plurality of through holes 131A, but has a long hole shape with a large cross-sectional area on the side of the supply port 41i for the reaction gas (air or hydrogen gas) in FIG. A through-hole 131A is provided, and a through-hole 131A having a smaller cross-sectional area toward the discharge port 41o is provided. Even in this modification, the effects described above can be achieved.

  The present invention is not limited to the above-described embodiments and modifications, and can be implemented in various modes without departing from the scope of the invention. For example, in order to widen the dividing region of the hole connection of the porous gas supply member 30 toward the supply port 41i side, the formation pitch of the notch grooves 31 is narrowed to increase the number, or the width of the notch grooves 31 is increased. However, by increasing the depth of the bottomed cutout groove 31, the dividing region can be made wider toward the supply port 41i. Further, even when forming a wavy notched groove, it may be a wavy notched groove in which a triangular wave or a rectangular wave is continuous, or a notched groove in which a triangular wave or a rectangular wave is divided.

  In providing the notch groove 31 in the gas supply member 30, in the above-described embodiment, the notch groove 31 is formed so as to be orthogonal to the gas flow. However, the notch groove 31 is formed so as to obliquely intersect the gas flow. You can also.

It is explanatory drawing which shows typically the structure of the fuel cell 10 which comprises the fuel cell as an Example of this invention in a cross section. 1 is a perspective view showing a schematic configuration of a gas supply member 30 constituting the fuel battery cell 10. It is a perspective view which shows schematic structure of 30 A of gas supply members of a modification. It is a perspective view showing a schematic structure of gas supply member 30B of another modification. It is explanatory drawing which shows the schematic structure of the gas supply member 30C of another modification by the plane and the side. It is explanatory drawing which shows schematic structure of gas supply member 30D of the modification of the aspect which cut off the notch groove. It is explanatory drawing which shows schematic structure of the gas supply member 30E of another modification by the planar view and the side view which fractured | ruptured the principal part. It is explanatory drawing which shows schematic structure of the modification of the gas supply member 30E of FIG. 7 by the planar view and the side view which fractured | ruptured the principal part. It is explanatory drawing which shows the schematic structure of the modification which deform | transformed the gas supply member 30F shown in FIG. 8 by the planar view and the side view which fractured | ruptured the principal part. It is explanatory drawing which shows schematic structure of the gas supply member 30H of the other modified example which has a through-hole by the planar view and the side view which fractured | ruptured the principal part. It is explanatory drawing which shows typically the structure of the fuel cell 100 of the other modification which comprises a fuel cell in a cross section. 2 is a perspective view showing a schematic configuration of a gas supply member 130 constituting the fuel cell 100. FIG. It is explanatory drawing which shows 130 A of gas supply members of the modification which has 131 A of through-holes along a rectangular side.

Explanation of symbols

10 ... Fuel cell 20 ... Membrane Electrode Assembly (MEA)
22 ... Gas diffusion member 24 ... Seal gasket 30, 30A-30H ... Gas supply member 31, 31A-31D ... Notch groove 31E-31G ... Through-hole 31H ... Through-hole 40 ... Separator 41i ... Supply port 41o ... Discharge port 100 ... Fuel cell 130, 130A ... Gas supply member 131, 131A ... Through hole 131d ... Lower part 131u ... Upper part

Claims (10)

A gas supply member for supplying a reaction gas while diffusing the reaction gas to the electrode in a membrane electrode assembly having an electrolyte membrane and electrodes joined to both sides of the electrolyte membrane,
Formed from a porous body, and the connection of the pores of the porous body as a gas flow path,
A gas supply member comprising: a hole dividing portion that divides the connection of the holes so as to intersect the flow of the reaction gas from the reaction gas supply side to the discharge side.   2. The gas supply member according to claim 1, wherein the hole dividing portion is made dense from the supply side to the discharge side so that a region where the connection is divided by the hole dividing portion becomes wider toward the supply side. .   The gas supply member according to claim 2, wherein the hole dividing portion is formed as a groove that intersects the flow of the reaction gas.   The gas supply member according to claim 3, wherein the groove serving as the hole dividing portion has a wave shape.   The gas supply member according to claim 3 or 4, wherein the groove as the hole dividing portion is formed continuously. A gas supply member according to any one of claims 3 to 5,
The gas supply member, wherein the groove as the hole dividing portion has a groove width wider toward the supply side or a larger number of grooves toward the supply side. A gas supply member according to any one of claims 3 to 6,
The groove as the hole dividing portion is formed as a bottomed groove. Gas supply member.   The gas supply member according to claim 1, wherein the hole dividing portion is formed in the porous body as a hollow portion.   The gas supply member according to claim 1, wherein the hole dividing portion is formed as a through hole penetrating the porous body. A fuel cell,
A fuel cell having a membrane electrode assembly having an electrolyte membrane and electrodes joined to both sides of the electrolyte membrane as a power generation unit;
A gas supply member that supplies the electrode while diffusing the reaction gas;
A fuel cell comprising the gas supply member according to any one of claims 1 to 9 as the gas supply member.

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