JP2009043453A - Fuel cell separator, its manufacturing method, and fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel cell separator having a passage for supplying a reaction gas in a fuel cell in which the fuel cell is made small in size by downsizing the passage. <P>SOLUTION: The separator 150 is provided with a first plate 151 and a second plate 155 of flat plate shape, and each plate has an oxygen passage rib 160 and a hydrogen passage rib 170 for forming a passage on the plate surface, and a coolant passage rib 162 is provided between these plates. Each of these ribs is formed by a cold drawing method using dice D in a cross-section of a cross-shape. The spacing between these ribs becomes an oxygen passage OR, a hydrogen passage HR, and a coolant passage RR, and each rib has a rib pitch P and a rib height h of about 100-1,000 μm owing to the characteristics of the cold drawing method, and dimensions of each passage become small. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention includes a fuel cell separator that forms a flow path for supplying a reaction gas to an electrode in a state of being stacked on a fuel battery cell having electrodes attached to both sides of an electrolyte membrane, a manufacturing method thereof, and a fuel cell separator The present invention relates to a fuel cell.

  The fuel cell includes a fuel cell having a membrane electrode assembly as a power generation unit, and a flow path for supplying a reaction gas to each electrode of the membrane electrode assembly is formed by a fuel cell separator. Since fuel cells generate electricity through an electrochemical reaction between hydrogen and oxygen, water is generated on the cathode side. When this generated water stays in the gas supply flow path to the cathode, so-called flooding occurs due to the blockage of the flow path, and various techniques for draining the generated water have been proposed (for example, Patent Document 1).

JP 2000-123848 A JP 2003-249246 A JP 2005-310586 A

  In these patent documents, grooves and recesses for generated water drainage are separately formed in the gas supply flow path separately from the flow paths, and water (product water) is captured in these grooves and recesses by capillary action, and then externally The water is discharged.

  In reality, the gas flow path of the separator cannot be reduced to an unnecessarily small size because it is a formation target of a groove or a recess that can capture water using a capillary phenomenon. In other words, the reduction in the size of the gas flow path contributes to the reduction in size and size in the cell stacking direction of the fuel cell. However, in the conventional technique described above, there is room for downsizing of the fuel cell from securing the dimensions of the gas flow path. It remains.

  An object of the present invention is to provide a fuel cell separator having a flow path for supplying a reaction gas in a fuel cell, and to reduce the size of the fuel cell by reducing the size of the flow path.

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

[Application 1: Fuel cell separator]
A separator for a fuel cell, which is used by being stacked on a fuel battery cell having electrodes attached to both sides of an electrolyte membrane, and forms a flow path for supplying a reactive gas to the electrode while being stacked with the fuel battery cell. And
With a plate,
A metal wire formed by wire drawing using a die is fixed in multiple rows on the cell facing surface of the plate on the side laminated with the fuel cells, and the fixed multi-row metal wires are provided. The gist is that the gap between them is the flow path.

[Application 2: Manufacturing method of fuel cell separator]
A method for producing a separator for a fuel cell, which is used by being laminated on a fuel cell provided with electrodes attached to both sides of an electrolyte membrane,
Prepare the plate,
On one surface of the plate, while forming a metal wire by wire drawing using a die, the metal wire is fixed to the surface of the plate to form a protrusion made of the metal wire, and the protrusion is The gist is to form in multiple rows on the surface of the plate.

  In the fuel cell separator described above, the flow path for supplying the reaction gas has gaps between metal wires formed in multiple rows through wire drawing using a die. In such wire drawing, for example, cold drawing of metal, due to its processing characteristics, metal wires having a cross-sectional shape following the opening shape of a die are accurately and easily arranged in multiple rows at fine intervals, for example, 100 to 1000 μm pitch. Can be formed. Moreover, the thickness (height) of the metal wire that becomes the height of the flow path can be set to about 100 to 1000 μm as described above. For this reason, the fuel cell can be reduced in size and size in the cell stacking direction by reducing the size of the flow path determined by the interval between the metal wires formed in multiple rows and the thickness (height) of the metal wires.

  In addition, as described above, the cross-sectional shape of the metal wire can be a cross-sectional shape that follows the opening shape of the die, and thus has the following advantages.

  The formation of grooves and recesses that capture water using capillary action in the reaction gas flow path is desired from the viewpoint of drainage to the outside, but such grooves and recesses do not cause capillary action. For the convenience of use, dimensional precision is required. It has been pointed out that, in order to form fine-sized grooves and recesses by cutting, a precision drive mechanism on the machine device side is required, and process management becomes complicated. In addition, there is a limit to the formation of fine grooves and recesses in press working, and it is not realistic to form grooves and recesses capable of catching water by press working using capillary action. In addition, it has been pointed out that etching using a photoresist method requires various processes such as resist printing and etching with an etching solution, resulting in complicated process management.

  However, in a fuel cell using the separator having the above-described configuration, that is, a fuel cell in which gaps between metal wires formed in multiple rows through wire drawing using dies are used as flow paths, the cross-sectional shape of the metal wire is Since a cross-sectional shape that follows the opening shape of the die can be formed, if the opening shape of the die is formed to form a depression in the metal wire, water existing in the flow path can be captured in the depression by capillary action. And since such a hollow becomes naturally smaller than the above-mentioned flow path dimension, in the flow path between metal wires, the hollow for capturing water by capillary action can be easily formed with a fine dimension. For example, even a small channel having a channel size of about 100 to 1000 μm described above can be easily reduced to about 30 to 500 μm finer than this. The depression of about 30 to 500 μm (preferably 30 to 100 μm) can achieve water trapping with high effectiveness by capillary action. This is synonymous with the fact that it is possible to avoid the blockage of the flow path due to water with high effectiveness, so that the pressure loss accompanying the blockage of the flow path can be alleviated and the reliability of the gas supply can be improved.

  And since the hollow of a fine dimension is continued along a metal wire, the water captured by the hollow can be made to continue easily. As a result, water trapped in the depression can be caused to flow along the flow path by a force (force based on the gas flow) generated while the reaction gas passes through the flow path between the metal wires. Can increase the sex. For example, when the fuel cell is operated at a low load for a long time, the reaction gas flow rate becomes slow, so the force based on the gas flow becomes small, and the trapped water tends to form water droplets or a water film. It is difficult to drain water, and water clogging is likely to occur. However, since the water drops and the water film are combined and water continues in the above-described depression, the water can be drained easily even with a small force. This is beneficial for maintaining the power generation capacity of the fuel cell.

  The fuel cell separator described above can be configured as follows. For example, a plate in which a flow path is formed by the above-described multi-row metal wires, a counter plate facing the plate, and a wire drawing process using a die between the counter plate and the plate The metal wires formed through the above are fixed in multiple rows, and the gap between the fixed multiple rows of metal wires is used as a flow path for the cooling medium between the opposed plate and the plate. In this way, a high cooling capacity can be exhibited due to an increase in the surface area of the flow path accompanying a reduction in the size of the medium flow path. Moreover, if the die shape is an irregular shape, the cooling capacity can be increased by further increasing the channel surface area.

  The present invention can also be applied to a fuel cell in which the above-described fuel cell separator is stacked on a fuel cell having electrodes on both sides of an electrolyte membrane. That is, in this fuel cell, the reaction gas is supplied from the fuel cell separator having the gas flow path between the metal wires to the electrode of the fuel cell provided with electrodes joined to both sides of the electrolyte membrane.

  Hereinafter, embodiments of the present invention will be described based on examples. FIG. 1 is an explanatory view schematically showing a configuration of a fuel cell 10 as an embodiment of the present invention, and FIG. 2 is a partially enlarged view showing a state of an oxygen flow path rib 160 formed in a separator used in the fuel cell 10. It is explanatory drawing.

  As shown in the figure, the fuel cell 10 of this embodiment has a stack structure in which a plurality of fuel cells 100 are stacked with a separator 150 interposed therebetween. In this case, the number of stacked fuel cells 100 in the fuel cell 10 can be arbitrarily set according to the output required for the fuel cell 10. The fuel cell 10 includes a manifold and a flow path along the cell stacking direction for distributing and supplying hydrogen as fuel gas, air as oxidant gas, and cooling water to each fuel cell 100. However, since these are not directly related to the gist of the present invention, their illustration and description are omitted.

  The fuel cell 100 includes a membrane electrode assembly (MEA) 110 in which electrodes 114 and 116 on both surfaces of an electrolyte membrane 112 having proton conductivity are joined, and gas diffusion for supplying reaction gas to each electrode in a diffused manner. The layers 120 and 122 are bonded and fixed, and one electrode is an anode and the other electrode is a cathode, and the membrane electrode assembly 110 is a power generation unit. Various electrolyte membranes 112 can be adopted, and can be a solid polymer membrane or an electrolyte membrane using a solid oxide or the like as an electrolyte. The gas diffusion layers 120 and 122 deliver the reaction gas (air at the cathode and hydrogen gas at the anode) while diffusing the electrodes 114 and 116 to which the gas diffusion layers 120 and 122 are bonded, respectively. The gas diffusion layers 120 and 122 are formed of a porous material such as a metal mesh or carbon paper, and supply the reaction gas supplied through the separator 150 while diffusing it to the electrodes 114 and 116, respectively. In this embodiment, for convenience of explanation, the electrode 114 and the side of the gas diffusion layer 120 bonded thereto are set as an anode, and the side of the electrode 116 and the gas diffusion layer 122 is set as a cathode.

  The fuel cell 100 and the separator 150 laminated and bonded on both sides thereof include a flat plate-like first plate 151 and a second plate 155, and ribs for channel formation are formed on the plate surface of each plate. Prepare. That is, the electrode 116 and the gas diffusion layer 122 on the cathode side are provided with the oxygen channel ribs 160 on the surface of the first plate 151, and the electrode 114 and the gas diffusion layer 120 on the anode side are on the surface of the second plate 155. And a refrigerant flow path rib 162 on the back surface (between the first and second plates) of the first plate 151, and each rib is covered with a conductive adhesive layer S on the plate surface. It is fixed to the adhesive. Each of these ribs is formed by a cold drawing method of a metal using a die, and the cross-sectional shape thereof is a cross shape as shown in the figure. In the oxygen flow channel rib 160, gas diffusion on the cathode side is formed. The hydrogen flow path ribs 170 are in contact with the gas diffusion layer 120 on the anode side. In this embodiment, the first plate 151 and the second plate 155 are stainless steel plates from the viewpoint of durability and workability, and each rib such as the oxygen flow path rib 160 is also formed from a stainless steel wire excellent in durability. did. And about the 1st plate 151 and the 2nd plate 155, the thickness shall be 100-200 micrometers, and the rib pitch P and rib height h of each rib, such as the rib 160 for oxygen flow paths, were made into the dimension of about 100-1000 micrometers. .

  The separator 150 has an oxygen passage OR between adjacent oxygen passage ribs 160, a refrigerant passage RR between adjacent refrigerant passage ribs 162, and a hydrogen between adjacent hydrogen passage ribs 170. The flow path is HR. These flow paths have a flow area determined by the rib pitch P and the rib height h described above.

  The separator 150 has holes for introducing and discharging gas / refrigerant to / from these flow paths. That is, as shown in FIG. 2, the separator 150 includes an air introduction hole 152i, a hydrogen gas introduction hole 153i, and a refrigerant introduction hole 154i on one end side of each rib such as the oxygen flow path rib 160, and the other end side. Are provided with an air discharge hole 152o, a hydrogen gas discharge hole 153o, and a refrigerant discharge hole 154o. In the flow path such as the oxygen flow path OR of the separator 150, oxygen, Hydrogen gas and cooling medium flow individually. The separator 150 supplies oxygen passing through the air introduction hole 152i to the gas diffusion layer 122 of the cathode through the oxygen passage OR between the oxygen passage ribs 160, and hydrogen gas passing through the hydrogen gas introduction hole 153i. A coolant such as water supplied to the anode gas diffusion layer 120 through the hydrogen flow path HR between the hydrogen flow path ribs 170 and passing through the refrigerant introduction hole 154i is supplied to the refrigerant flow path RR between the refrigerant flow path ribs 162. Pass through. Each fuel cell 100 of the fuel cell 10 supplies oxygen in the air and hydrogen in the hydrogen gas supplied from the separator 150 to the cathode / anode from the separator 150 in an electrode reaction by the membrane electrode assembly 110 to generate power. The fuel cell 10 collects the power generated by these cells and outputs the collected power to the outside. In addition to the surplus air and hydrogen gas, the separator 150 discharges generated water and refrigerant accompanying power generation to the outside through the air discharge hole 152o, the hydrogen gas discharge hole 153o, and the refrigerant discharge hole 154o.

  Next, the manufacturing procedure of the fuel cell 10 of the present embodiment having the above-described configuration will be described. FIG. 3 is a flowchart showing the manufacturing procedure of the fuel cell 10. In manufacturing the fuel cell 10, the separator 150 and the fuel cell 100 are prepared or prepared sequentially or in parallel, and then the fuel cells 100 and 150 are stacked. For this reason, in this embodiment, first, the first plate 151 and the second plate 155 are prepared for the production of the separator 150 (step S100). In preparing the plate, a stainless steel plate is subjected to a roll press / punch press, and the outer shape is punched as shown in FIG. The Alternatively, plates whose outer shapes and holes have already been punched are prepared as the first plates 151 and 155.

  In steps S110 to S120 following the plate preparation, the first plate 151 is provided on both sides thereof, the second plate 155 is provided on one side thereof, and oxygen channel ribs 160, refrigerant channel ribs 162, and hydrogen channels are formed by metal wires. The rib 170 for use is formed. Both of these steps can be executed sequentially as shown, or in the reverse order or in parallel. FIG. 4 is an explanatory view schematically showing a state in which the oxygen flow path rib 160 is formed on one surface of the first plate 151 by a cold metal drawing method using a die D. FIG. As shown in FIGS. 4 and 2, the first plate 151 is set in a cold drawing device (not shown), and the metal line in which the stainless wire is cold drawn from the die hole DH in the die D is connected to the first plate 151. The plate is formed in a row so as to overlap the row of adhesive layers S extending from one end of the plate to the other end. In the present embodiment, as shown in FIG. 4, since the die hole DH has a cross-shaped opening shape, the cold-drawn metal line has a cross-shaped cross section following the opening shape of the die hole DH. It is formed so that the lower end side flat portion in the cross section is in contact with the row-shaped adhesive layer S.

  The adhesive layer S is cured, for example, heated or cooled, and the metal line is bonded and fixed by the adhesive layer S to form the oxygen channel rib 160. The oxygen channel rib 160 are formed in multiple rows on the surface of the first plate 151 with the rib pitch P and the rib height h described above. In the first plate 151, the refrigerant flow path ribs 162 are formed in multiple rows on the back surface of the plate by the same method as described above. In step S120, the hydrogen flow path ribs 170 are formed in multiple rows on one surface of the second plate 155 by the same method as described above.

  As shown in FIG. 4, the adhesive layer S can be pre-applied in multiple rows of adhesives (conductive adhesives), and can be applied to the adhesive surface of a metal line that is cold drawn from the die D. An adhesive (conductive adhesive) can also be applied. In this example, in order to ensure the heat conductivity, conductivity, and corrosion resistance of the adhesive layer S, a conductive adhesive in which gold powder was mixed as a further conductive filler in a commercially available conductive epoxy adhesive was used.

  In the subsequent step 130, as described above, the oxygen plate rib 160 and the refrigerant channel rib 162 are formed on the first plate 151, and the hydrogen channel rib 170 is formed on the second plate 155. The refrigerant flow path ribs 162 are joined so as to be sandwiched between both plates, and fixed with an adhesive. Thereby, the separator 150 is obtained. Note that the adhesive used for bonding in step S130 and the adhesive used for forming the refrigerant flow path rib 162 in step S120 do not necessarily need to be conductive adhesives, but are easy to handle and manage. In this example, the above-described conductive adhesive was used.

  In subsequent step 140, a predetermined number of gas diffusion layers 120, gas diffusion layers 122, fuel cells 100 bonded to each other and separators 150 obtained in step 130 are stacked on both sides of the membrane electrode assembly 110 to form fuel. A battery stack is formed, and current collector plates and end plates are disposed at both ends of the fuel cell stack, and the fuel cell stack is fastened along the cell stacking direction (step S150) to obtain the fuel cell 10.

  As described above, in the present embodiment, when a plurality of fuel cells 100 each having the fuel cell 100 and the separator 150 are stacked to form the fuel cell 10, the reaction gas is applied to the cathode and anode of each fuel cell 100. The separator 150 forms a flow path (oxygen flow path OR and hydrogen flow path HR) for supplying air and hydrogen gas. The separator 150 includes, on the cathode side and the anode side, a plurality of rows of oxygen flow channel ribs 160 made of metal wires using dies D on the surface of the first plate 151, and the surface of the second plate 155 is the same. The hydrogen flow path ribs 170 made of metal wires are provided in multiple rows, the gap between the row oxygen flow path ribs 160 is defined as an oxygen flow path OR, and the gap between the hydrogen flow path ribs 170 is defined as a hydrogen flow path HR.

  Since the oxygen channel rib 160 and the hydrogen channel rib 170 have undergone a cold drawing method of metal using the die D, the processing characteristics of the oxygen channel rib 160 and the hydrogen channel rib 170 follow the opening shape of the die hole DH of the die D. The oxygen channel rib 160 and the hydrogen channel rib 170 can be formed in multiple rows accurately and easily with a fine rib pitch P and a rib height h of about 100 to 1000 μm. Since the sizes of the oxygen channel OR and the hydrogen channel HR are determined by the rib pitch P of the ribs formed in multiple rows and the rib height h of each rib, in this embodiment, the oxygen channel OR and the hydrogen channel HR are determined. The flow path HR can be reduced in size to the extent described above. As a result, in the fuel cell 10 having the separator 150 of the present embodiment, the size of the battery can be reduced by the small size of the fuel cell 100 in the cell stacking direction.

  Further, in this embodiment, as described above, the oxygen channel rib 160 and the hydrogen channel rib 170 are cross-shaped ribs, and thus have the following advantages. FIG. 5 is an explanatory view schematically showing how water is captured and discharged by using the cross-section oxygen flow path rib 160. In the drawing, the first plate 151 is seen through to draw the oxygen channel rib 160.

  As shown in the figure, since the cross section of the oxygen channel rib 160 is a cross shape, the cathode electrode surface, specifically, the surface side of the gas diffusion layer 122 constituting the cathode and the surface side of the first plate 151 are illustrated. At the same time, two depressions 161 are formed. On the gas diffusion layer 122 side, the depression 161 is surrounded on three sides by the diffusion layer surface and the rib surface, and on the first plate 151 side, the three sides are surrounded by the plate surface and the rib surface. Since the oxygen channel rib 160 itself is about 100 to 1000 μm as described above, the size of the recess 161 is smaller than the rib size, and has a fine size of about 50 to 500 μm. The depression 161 continues along the oxygen channel rib 160 with such a fine dimension.

  On the cathode surface, specifically, the surface of the gas diffusion layer 122, the water produced by the electrochemical reaction between oxygen and hydrogen is present in the form of fine water droplets or water films. Because of the fine dimensions described above, as shown in FIG. 5, they are easily and surely captured by the depression 161 by the capillary phenomenon, and gathered and united in the depression, and are easily continuous along the depression 161. By capturing the water in the depression 161, the flow passage area of the oxygen passage OR can be secured in a range excluding the depression 161, so that blockage of the passage due to water can be avoided and the reliability of air supply can be improved. Further, in the state where the water is trapped as described above, the air surely passes through the oxygen channel OR in a range excluding the depression 161, so that the water already captured in the depression 161 is caused to flow into the oxygen channel by this air flow. It flows along the rib 160 for use. In this case, since the water is continuous in the depression 161 as described above, the water already trapped in the depression 161 can be easily and reliably flowed along the oxygen flow path rib 160 even by a slight air flow. It can be discharged outside the cell. Therefore, it is possible to maintain or improve the power generation performance by suppressing the power generation performance of the fuel cell 10 due to the blockage of water with high effectiveness. More specifically, when the fuel cell 10 is operated for a long time at a low load, the amount of air supplied is small and the flow rate is slow, but even in such a situation, the depression 161 Since the captured water can be easily and reliably drained outside the cell, the power generation capacity of the fuel cell 10 can be reliably maintained. The above drainage is exhibited by the hydrogen flow path ribs 170 also on the anode side.

  In this embodiment, it is possible to easily manufacture the separator 150 having high water drainage, and thus the fuel battery cell 100 and the fuel battery 10 having the separator 150.

  The oxygen channel rib 160 of the above-described embodiment forms the depression 161 on the surface side of the cathode, more specifically, the surface of the gas diffusion layer 122, and captures water on the surface of the diffusion layer. Therefore, in the range of the dent 161 where water has been captured, the surface of the diffusion layer is blocked with water, and air does not enter from the surface. However, since the dimension of the depression 161 is smaller than the dimension of the oxygen flow path OR between the ribs, a sufficient range can be secured except for the depression 161 that has already captured water, and air enters the gas diffusion layer 122 in this range. Since this happens, there is no particular hindrance.

  Further, in this embodiment, the refrigerant flow path rib 162 is formed between the first plate 151 and the second plate 155 by a cold drawing method using the die D, and the gap between the ribs is defined as the refrigerant flow path RR. did. Even in the refrigerant flow path RR, the size is reduced as described above. For this reason, size reduction of the fuel cell 10 can be advanced with size reduction of the refrigerant | coolant flow path RR.

  In addition, the size of the refrigerant flow path RR is reduced, and the hydrogen flow path rib 170 for forming the flow path is formed into a cross-shaped cross-section rib, so that the flow path surface area of the refrigerant flow path RR can be increased. . For this reason, the cooling capacity can be easily increased by using the separator 150 of the present embodiment.

  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, the ribs made of metal lines such as the oxygen flow path ribs 160 formed on the first plate 151 and the second plate 155 of the separator 150 are not limited to the cross shape and can be variously set. FIG. 6 is an explanatory view for explaining the oxygen flow path rib 160 and the state of water capture in a modified example.

  As shown in the figure, the oxygen channel rib 160 can have various cross-sectional shapes. In addition to the trapezoidal cross-sectional shape as shown in FIG. 6A, the H-shaped cross-sectional shape shown in FIG. C) and a circular cross-sectional shape shown in FIG. The trapezoidal cross-section oxygen channel rib 160A shown in FIG. 6 (A) is joined to the cathode on the trapezoid bottom side so that the top surface of the trapezoid is surrounded by a V-shape with the surface of the first plate 151 and the trapezoid hypotenuse. The hollow 161A is formed, water is captured in the hollow by capillary action and drained outside the cell. Since the recess 161A is separated from the cathode surface, water can be separated from the cathode surface, specifically, the surface of the gas diffusion layer 122, so that the entry of air into the gas diffusion layer 122 can be prevented.

  The oxygen flow channel rib 160B having an H-shaped cross section shown in FIG. 6B is joined to the cathode as shown in the figure to form a recess (recess) 161B surrounded by the rib on three sides, Water is captured in the depression by capillary action and drained outside the cell. Even in the depression 161B, since it is away from the cathode surface, it is possible to prevent the air from entering the gas diffusion layer 122. The oxygen flow channel rib 160C having a T-shaped cross section shown in FIG. 6C is joined to the cathode as shown in the figure, so that a recess 161C surrounded by the surface of the first plate 151 and the ribs on three sides is formed. Is formed away from the cathode, and water is captured in the depression by capillary action and drained outside the cell. Even in the depression 161C, since it is away from the cathode surface, it is possible to prevent the air from entering the gas diffusion layer 122. The oxygen flow channel rib 160D having a circular cross-sectional shape shown in FIG. 6D is joined to the cathode as shown in the figure to form a depression 161D on the cathode side and the first plate 151 side, and a capillary tube is formed in the depression. Water is captured by the phenomenon and drained outside the cell. The oxygen channel rib 160D is formed with a recess 161D on the surface of the gas diffusion layer 122 as in the oxygen channel rib 160 of the above embodiment. However, as described above, air enters the gas diffusion layer 122. There is no particular hindrance.

  In addition to the shape of the oxygen flow path rib 160 other than the shape shown in FIG. 6, the oxygen flow path rib 160A and the oxygen flow path rib 160C shown in FIGS. It can also be an inverted rib. Further, in addition to the oxygen flow channel ribs having the same shape in multiple rows, the oxygen flow channel ribs having different shapes, for example, the oxygen flow channel rib 160 having a cross-sectional shape shown in FIG. 1 and H shown in FIG. Alternatively, the separator 150 may be provided in multiple rows by alternately arranging the oxygen flow path ribs 160B having a cross-sectional shape.

  Also, as shown in FIG. 4, when the oxygen flow path rib 160 is formed by the cold drawing method using the die D, the rib surface and the surface of the first plate 151 can be coated with gold. This is preferable because the conductivity at the joint between the rib and the plate is increased. Furthermore, if the separator 150 having the adhesive layer S bonded and fixed with the oxygen flow path rib 160, the hydrogen flow path rib 170, etc. is carbon coated on the whole, the conductive filler of the adhesive layer S is protected and the corrosion resistance is ensured. From the point of view, it is preferable.

It is explanatory drawing which shows roughly the structure of the fuel cell 10 as an Example of this invention. 4 is an explanatory view showing a partially enlarged state of an oxygen flow path rib 160 formed in a separator used in the fuel cell 10. FIG. FIG. 3 is a procedure diagram showing a manufacturing procedure of the fuel cell 10. It is explanatory drawing which shows typically a mode that the rib 160 for oxygen flow paths is formed in the one surface of the 1st plate 151 by the cold drawing method of the metal which used the dice | dies D. FIG. It is explanatory drawing which shows typically the mode of the capture | acquisition / discharge of water by using the rib 160 for oxygen flow paths of a cross section. It is explanatory drawing explaining the rib 160 for oxygen flow paths of a modification, and the mode of water capture | acquisition.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Fuel cell 100 ... Fuel cell 110 ... Membrane electrode assembly 112 ... Electrolyte membrane 114 ... Electrode 116 ... Electrode 120 ... Gas diffusion layer 122 ... Gas diffusion layer 150 ... Separator 151 ... First plate 152i ... Air introduction hole 152o ... Air discharge hole 153i ... Hydrogen gas introduction hole 153o ... Hydrogen gas discharge hole 154i ... Refrigerant introduction hole 154o ... Refrigerant discharge hole 155 ... Second plate 160, 160A-160D ... Oxygen flow path rib 161, 161A-161D ... Depression 162 ... Refrigerant flow path 170 ... Hydrogen flow path rib S ... Adhesive layer P ... Rib pitch h ... Rib height D ... Dice DH ... Dice hole OR ... Oxygen flow path RR ... Refrigerant flow path HR ... Hydrogen flow path

Claims (6)

A separator for a fuel cell, which is used by being stacked on a fuel battery cell having electrodes attached to both sides of an electrolyte membrane, and forms a flow path for supplying a reactive gas to the electrode while being stacked with the fuel battery cell. And
With a plate,
A metal wire formed by wire drawing using a die is fixed in multiple rows on the cell facing surface of the plate on the side laminated with the fuel cell, and the fixed multi-row metal wires are provided. A fuel cell separator having a gap therebetween as the flow path.   2. The fuel cell separator according to claim 1, wherein the metal wire has a cross-sectional shape having a recess for capturing the water on the metal wire side by capillary action when water is present in the flow path. The fuel cell separator according to claim 1 or 2,
An opposing plate facing the plate, and a metal wire formed by wire drawing using a die fixed between the opposing plate and the plate in multiple rows, the fixed multiple rows A separator for a fuel cell in which a gap between the metal wires is used as a cooling medium flow path between the opposing plate and the plate. A method for producing a separator for a fuel cell, which is used by being laminated on a fuel cell provided with electrodes attached to both sides of an electrolyte membrane,
Prepare the plate,
While forming a metal wire on one surface of the plate by wire drawing using a die, the metal wire is fixed to the surface of the plate via a conductive adhesive, and is formed from the metal wire. And a method for producing a separator for a fuel cell, wherein the protrusions are formed in multiple rows on the surface of the plate.   The method for producing a fuel cell separator according to claim 4, wherein the metal wire is formed by cold drawing of the metal as the wire drawing. A plurality of fuel battery cells each having an electrode bonded to both sides of the electrolyte membrane and a plurality of fuel cell separators that form a flow path for supplying a reaction gas to the electrode while being stacked with the fuel battery cells A fuel cell,
The fuel cell separator is a fuel cell separator according to claim 1 or 3 or a fuel cell separator manufactured by the method according to claim 4.

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