JP2019129032A - Fuel battery and assembling method of the fuel battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel cell capable of suppressing the generation of a gap between a fuel cell and a heat insulating material. According to the present embodiment, a fuel cell includes an electrolyte membrane, an oxidant electrode channel plate provided with an oxidant electrode channel facing an oxidant electrode of the electrolyte membrane, and a fuel of the electrolyte membrane. A fuel cell flow channel plate provided with a fuel electrode flow channel facing the electrode, and a cell stack body in which a plurality of fuel cells are stacked, and a cell stack body from both end surfaces in the stacking direction of the cell stack body. And a plurality of connectors for connecting the two tightening plates, and a self-adhesive heat insulating material portion that covers at least a part of the front surface and the back surface of the two tightening plates. .. [Selection diagram] Fig. 9

Description

  Embodiments described herein relate generally to a fuel cell and a method for assembling the fuel cell.

The fuel cell generates electricity by the electrochemical reaction in the electrolyte membrane of the fuel electrode gas and the oxidant electrode gas. The fuel cell has a high energy recovery efficiency compared to other energy agencies, and because there is almost no discharge of no _x and so _x, it is possible to further reduce the impact on the global environment. For this reason, development of fuel cells for home use and in-vehicle use is underway.

  The fuel cell includes an electrolyte membrane, a fuel electrode channel plate provided with a channel along the fuel electrode of the electrolyte membrane, and an oxidant electrode provided with a channel along the oxidant electrode of the electrolyte membrane. Power is generated using a cell stack in which fuel cells having a flow path plate are stacked. In addition, the cell stack can generate heat during power generation, and this heat can be recovered and used. In order to maintain the heat recovery efficiency of the cell stack, it is necessary to prevent the heat dissipation of the cell stack.

  However, this fuel cell generally has a clamping plate for clamping the cell stack, a connector for coupling the clamping plate, and the like. For this reason, even if it is going to cover a fuel cell with the heat insulating material which has a softness | flexibility etc., there exists a possibility that a clearance gap may arise with a connector etc. and heat insulation performance may fall.

  In addition, since each of the fuel cells forming the cell stack generates heat during power generation, both ends of the cell stack have higher heat dissipation than the central portion and a lower temperature than the central portion. For this reason, the heat recovery efficiency of the fuel cells at both ends is lowered.

JP 2004-87344 A

  The problem to be solved by the present invention is to provide a fuel cell in which the heat insulating material can be disposed without any gap on a predetermined surface of the fuel cell.

  According to the present embodiment, the fuel cell includes an electrolyte membrane, an oxidant electrode channel plate provided with an oxidant electrode channel facing the oxidant electrode of the electrolyte membrane, and a fuel electrode of the electrolyte membrane. A fuel cell stack having a plurality of fuel cells stacked thereon, and a fuel cell flow plate having a facing fuel cell flow path, and the cell stack from both end sides in the cell lamination direction. Two fastening plates to be fastened, a plurality of couplers for connecting the two fastening plates, and a self-adhesive heat insulating material portion covering at least a part of the front surface and the back surface of the two fastening plates. .

  According to the present invention, the heat insulating material can be disposed without any gap with respect to the predetermined surface of the fuel cell.

The perspective view which shows the structure of the fuel cell stack which removed the manifold. The perspective view which shows the structure of the fuel cell stack of the state which mounted | wore the manifold. The disassembled perspective view which shows the structure of a fuel cell. The figure which shows the structure of a fuel electrode flow-path board. The figure which shows the structure of an oxidizing agent electrode flow-path board. The figure which shows the structure and terminal of the front side of a clamping board. The figure which shows the structure of the back surface of a clamping board. The figure which shows the heat insulating material part arrange | positioned in the hollow structure of a clamping plate. The figure which covered the area | region containing the surface of a clamping plate, and the connection part of a terminal with a heat insulating material part. The figure which covered the back of the manifold with the heat insulating material part.

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings attached to the present specification, for the sake of easy illustration and understanding, the scale, the dimensional ratio in the vertical and horizontal directions, etc. are appropriately changed from those of the actual one and exaggerated.

(One embodiment)
FIG. 1 is a perspective view showing the structure of the fuel cell 1 with the manifold removed. FIG. 2 is a perspective view showing the structure of the fuel cell 1 in a state where the manifold is mounted. As shown in FIGS. 1 and 2, the fuel cell 1 according to the first embodiment is a structure that generates electric power by an electrochemical reaction in a fuel cell. That is, the fuel cell 1 includes a cell stack 10, two current collector plates 20, two insulating plates 25, a fuel cell fastening structure 30, a first manifold 40, a second manifold 42, The third manifold 44 and the fourth manifold 46 are provided. The cell stack 10 is a stack of a plurality of fuel cells 10a. The fuel cell 10a generates electric power by an electrochemical reaction between a fuel electrode gas containing hydrogen and an oxidant electrode gas containing oxygen. That is, the cell stack 10 is a structure in which a plurality of fuel cells 10a are connected in series. The detailed configuration of the fuel cell 10a will be described later. 1 and 2 show a Z direction parallel to the stacking direction of the cell stack 10, and an X direction and a Y direction perpendicular to the Z direction and parallel to each other. When the fuel cell 1 of the present embodiment is installed on a horizontal surface, the Z direction is parallel to the gravity direction.

  Two current collectors 20 are disposed on both sides of the cell stack 10 in the stacking direction. The two current collectors 20 are plate-like conductors and are disposed on each of both end surfaces of the cell stack 10. The two insulating plates 25 are plate-like insulators and are respectively disposed between the two current collecting plates 20 and the two fastening plates 100. As described above, the two current collector plates 20 and the two insulating plates 25 are sequentially arranged on both sides in the stacking direction of the cell stack 10, and these two fastening plates are integrally formed from both sides in the stacking direction. By fastening with 100, the fuel cell 1 is obtained.

  The fuel cell clamp structure 30 is a structure that applies a surface pressure to the cell stack 10, and includes two clamp plates 100 and a plurality of connectors 200. The two clamping plates 100 are members that clamp the cell stack 10 from both sides in the stacking direction of the cell stack 10 in which a plurality of fuel cells are stacked. The clamping plate 100 has a pressing portion 110 and a beam portion 120. The pressing part 110 and the beam part 120 are integrally formed. The pressing portion 110 and the beam portion 120 may be separately configured.

  The connection tool 200 is a member that connects the two fastening plates 100. That is, the connector 200 in the present embodiment includes the tie rod 202, the two washers 204, and the two nuts 206. As shown in FIG. 1, a nut 206 is tightened via a washer 204 in a state where tie rods 202 are passed through opposing holes provided in the two tightening plates 100, and the two tightening plates 100 are connected. ing.

  As shown in FIG. 2, manifolds 40, 42, 44, 46 are mounted on the side surfaces along the stacking direction of the cell stack 10 in the fuel cell 1. The manifold is a member having a space region for supplying a reaction gas such as a fuel electrode gas and an oxidant electrode gas, cooling water, and the like.

  The first manifold 40 has a cooling water manifold and an oxidant electrode manifold. The second manifold 42 is a fuel electrode manifold. The third manifold 44 is a manifold facing the first manifold 40, and includes a cooling water manifold and an oxidant electrode manifold. That is, the first manifold 40 and the third manifold 44 are respectively disposed on opposite side surfaces of the cell stack 10.

  The fourth manifold 46 is a manifold facing the second manifold 42 and is a fuel electrode manifold. That is, the second manifold 42 and the fourth manifold 46 are respectively disposed on opposite side surfaces of the cell stack 10.

  The cooling water introduced from the pipe joint portion 40a is supplied from the side surface of the cell stack 10, and is discharged from the pipe joint portion 44a via the cooling water flow channel groove of the fuel cell 10a. On the other hand, the oxidant electrode gas is introduced from the pipe joint part 40b, and the oxidant electrode gas that has not been consumed by the electrochemical reaction in the cell stack 10 is discharged from the pipe joint part 40c. In addition, the fuel electrode gas is introduced from the piping joint portion 42a, and the fuel electrode gas not consumed by the electrochemical reaction in the cell stack 10 is discharged from the piping joint portion 42b.

  The manifolds 40, 42, 44, and 42 are required to have gas impermeability. Also, the pressure inside the manifold is higher than the outside of the manifold. For this reason, the manifolds 40, 42, 44, 42 are generally configured as molded articles of rigid resin or metal that can withstand pressure differences between the inside and the outside of the manifold.

  The detailed configuration of the fuel cell unit 10 a according to the first embodiment will be described based on FIGS. 3 to 5. FIG. 3 is an exploded perspective view showing the configuration of a fuel cell according to one embodiment. As shown in FIG. 3, the fuel battery cell 10 a includes an electrolyte membrane 12, a fuel electrode flow path plate 14, and an oxidant electrode flow path plate 16. In the electrolyte membrane 12, a fuel electrode is formed on one main surface 12a, and an oxidant electrode is formed on the other main surface 12b. The electrolyte membrane 12 is, for example, a polymer electrolyte membrane.

  FIG. 4 is a view showing the configuration of the fuel electrode flow path plate 14, and FIG. 4 (a) is a view showing the shape of the fuel flow path plate 14 on the main surface 14 a side, and FIG. FIG. 4 is a view showing the shape of the main surface 14b side of the fuel electrode flow path plate 14; As shown in FIG. 4A, the major surface 14a of the fuel electrode channel plate 14 is on the opposite side of the fuel electrode of the electrolyte membrane 12, and forms a flat surface.

  As shown in FIG. 4B, the fuel electrode channel plate 14 forms a fuel electrode gas channel groove 140b along the fuel electrode on the main surface 14b of the electrolyte membrane 12 on the fuel electrode side. In addition, the fuel electrode gas flow channel 140b has a first inlet 14c, a first outlet 14d, a second inlet 14e, and a second outlet 14f. The fuel electrode gas introduced from the first inlet portion 14c flows along the fuel electrode gas flow channel 140b and is discharged from the first outlet portion 14d. Also, the fuel electrode gas introduced from the second inlet portion 14e flows along the fuel electrode gas flow channel 140b and is discharged from the second outlet portion 14f.

  FIG. 5 is a view showing the structure of the oxidant electrode flow channel plate 16, and FIG. 5 (a) is a view showing the shape of the main surface 16a of the oxidant electrode flow channel plate 16, and FIG. These are figures which show the shape of the main surface 16b on the opposite side to the main surface 16a of the oxidizing agent electrode flow-path board 16. FIG. As shown in FIG. 5A, the oxidant electrode channel plate 16 forms an oxidant gas channel groove 160a along the oxidant electrode on the main surface 16a of the electrolyte membrane 12 on the oxidant electrode side. ing. Further, the fuel electrode gas flow channel 160a has a first inlet 16c, a first outlet 16d, a second inlet 16e, and a second outlet 16f. The oxidant gas introduced from the first inlet 16c flows along the oxidant gas flow channel 160b and is discharged from the first outlet 16d. The oxidant gas introduced from the second inlet portion 16e flows along the oxidant gas flow channel 160b and is discharged from the second outlet portion 16f.

  As shown in FIG. 5B, the cooling water flow channel 160b is formed on the main surface 16b opposite to the oxidant electrode side. The cooling water flow channel 160b has a first inlet 16h and a first outlet 16g. The cooling water introduced from the first inlet 16h flows along the cooling water flow channel 160b and flows out from the first outlet 16g. The oxidant electrode channel plate 16 is made of, for example, a conductive porous plate having fine pores. Further, the cooling water flow channel 160b evaporates the cooling water from the surface thereof and humidifies the fuel cell. In addition, you may use the oxidizing agent electrode flow-path plate 16 which does not have the cooling water flow-path groove | channel 160b. In the case of using the oxidant electrode channel plate 16 without the cooling water channel groove 160b, the first manifold 40 and the fourth manifold 46 may be configured only by the oxidant electrode manifold.

  The plurality of fuel cells 10a generate power by the reaction represented by Chemical Formula 1. More specifically, the fuel electrode gas is, for example, a hydrogen-containing gas. The fuel electrode gas flows along the fuel electrode gas channel groove 140b of the fuel electrode channel plate 14 and causes a fuel electrode reaction. The oxidant gas is, for example, an oxygen-containing gas. The oxidant gas flows along the oxidant gas channel groove 160 a of the oxidant electrode channel plate 16 to cause an oxidant electrode reaction. The fuel cell stack utilizes these electrochemical reactions to extract electrical energy from the electrodes provided on the collector plate 20 (FIG. 1).

(Chemical formula 1)
Fuel electrode reaction: H ₂ → 2H ⁺ + 2e
Oxidizer electrode ^{_{reaction: 1 / 2O 2 + 2H +}} + 2e - → H 2 O

  The heat insulating material part 400 arrange | positioned to the back surface of the clamping plate 100 is demonstrated based on FIG. 6 thru | or FIG. FIG. 6 is a view showing the configuration of the front side of the clamping plate 100 and the terminals 300. As shown in FIG. As shown in FIG. 6, the terminal 300 and the terminal cover 310 are attached to the clamping plate 100. The terminal 300 is electrically connected to the current collector plate 20.

  FIG. 7 is a view showing the configuration of the back surface of the fastening plate 100. As shown in FIG. 7, the inside of the beam portion 120 (FIG. 1) has a hollow fastening plate 100 shape. That is, the back surface of the fastening plate 100 has a concave shape in the stacking direction except for the pressing portion 100. Thus, the fastening plate 100 has a hollow structure on the surface facing the cell stack 10 (FIG. 1). As described above, the terminal 300 and the terminal cover 310 (FIG. 6) are attached to the opening 340.

  FIG. 8 is a view showing the heat insulating material portion 400 arranged in the hollow structure of the fastening plate 100. As shown in FIG. 8, the heat insulating material portion 400 is disposed in the hollow structure of the fastening plate 100. The heat insulating material part 400 is a self-adhesive insulating material, for example, a flame-retardant rigid urethane foam. That is, the flame retardant rigid urethane foam is flame retardant and insulative at the temperature during operation of the fuel cell. More specifically, the flame retardancy of the self-adhesive heat insulating material constituting the heat insulating material portion 400 satisfies the standards of UL94 and HF-1, for example. The insulation of the heat insulating material constituting the heat insulating material part 400 is, for example, 100 MΩm or more, the heat resistant temperature of the heat insulating material is, for example, 80 ° C. or more, and the thermal conductivity is, for example, 0.034 W / mK or less.

  When the heat insulating member 400 disposed in the hollow structure of the fastening plate 100 is configured, the fastening plate 100 is attached to the cell laminate 100 as shown in FIG. Then, a liquid or shaving cream-like self-adhesive insulating material is injected from the end of the fastening plate 100 extending over the opening 340. As a result, the liquid or shaving cream self-adhesive insulating material foams in the hollow structure of the clamping plate 100. Then, the foamed self-adhesive insulating material is cured to form the heat insulating material portion 400. Thus, when the heat insulating material part 400 is configured in the hollow structure of the fastening plate 100, gaps or small holes between the fastening plate 100 and the insulating plate 25 (FIG. 1) are filled. Thereby, the heat insulation of the clamping board 100 improves more. That is, the heat insulation properties at both ends of the stacked cell 100 are further improved.

  In addition, the heat insulating material portion 400 can be configured after the fastening plate 100 is attached to the cell stack 10. Thereby, it is avoided that the attachment of the fastening plate 100 to the cell laminate 10 and the adjustment of the fastening pressure are hindered.

  In the cell stack 10 in the case where the heat insulating member 400 is disposed in the hollow structure of the fastening plate 100, the heat radiation of the fuel cell at both ends is suppressed. When the heat insulating material part 400 is not arranged in the hollow structure of the fastening plate 100, the temperature of the fuel cell at both ends of the cell stack 10 is increased by radiating heat on the fastening plate 100 side even if heat is generated. As a result, a temperature difference occurs between the central portion and both end portions of the cell stack 10 to reduce the heat recovery efficiency. However, when the heat insulating material part 400 is disposed in the hollow structure of the fastening plate 100, the heat dissipation of the fuel battery cells at both ends is suppressed by keeping the temperature of the cell stack 10 by the heat insulating material part 400. Thus, the temperature does not decrease, the temperature becomes uniform at the center and both ends of the cell stack 10, and the heat recovery efficiency is improved.

  FIG. 9 is a view in which a region including the surface of the clamping plate 100 and the connection portion between the terminal 300 and the current cable 350 is covered with the heat insulating material 400. As shown in FIG. 9, since the heat insulating material portion 400 covers the region including the connection portion with the current cable 350 with the insulating heat insulating material portion 400, the leakage is suppressed even if water leakage or the like occurs. . In addition, since the heat insulating material integrally covers the surface of the clamping plate 100 as well, the heat insulating property on the end side of the cell stack 10 is further improved.

  FIG. 10 is a view in which the back surfaces of the manifolds 40, 42, 44, 42 are covered with a heat insulating material part 400. As shown in FIG. 10, by covering the back surfaces of the manifolds 40, 42, 44, 42 with the heat insulating material portion 400, the heat radiation from the manifolds 40, 42, 44, 42 is also suppressed. Further, by covering the entire fuel cell with the heat insulating material portion 400 except for the pipe joint portions 40a, 40b, 40c, 42a, 42b, 44a, both ends of the tie rod 202, the washer 204, and the nut 206, heat dissipation can be further suppressed. It becomes possible. Note that both ends of the tie rod 202, the washer 204, and the nut 206 may be covered with the heat insulating material 400.

  In this way, the cell stack 10 is connected to the two clamp plates that clamp the cell stack 10 from both end surfaces in the stacking direction of the cell stack 10, and the manifolds 40, 42, 44, 42 are attached, The heat insulating material part 400 is constituted by a self-adhesive foam heat insulating material. Thereby, even after the fuel cell 1 is assembled, the heat insulating material part 400 can be configured by the self-adhesive foam heat insulating material. Further, even after the fuel cell 1 is assembled, the generation of a gap between the fuel cell 1 and the heat insulating material part 400 can be suppressed by the heat insulating material part 400 itself.

  As described above, according to the present embodiment, at least a part of the front surface and the back surface of the two fastening plates 100 is covered with the self-adhesive heat insulating material portion. Thereby, the temperature difference between the end portion and the center portion of the cell stack 10 is reduced, and the power generation efficiency of the fuel cell 10a can be made more uniform in the cell stack 10.

  In addition, since the heat insulating material part 400 is constituted by the self-adhesive foam heat insulating material, the heat insulating material part 400 can be arranged without a gap with respect to a predetermined surface of the fuel cell 1.

  1: fuel cell, 10: cell stack, 10a: fuel cell, 20: current collector plate, 25: insulating plate, 40: first manifold, 42: second manifold, 44: third manifold, 46: fourth Manifold, 100: Clamping plate, 200: Connector, 300: Terminal, 400: Thermal insulation part

Claims (6)

An electrolyte membrane, an oxidant electrode channel plate provided with an oxidant electrode channel facing the oxidant electrode of the electrolyte membrane, and a fuel electrode channel facing the fuel electrode of the electrolyte membrane are provided. A cell laminate in which a plurality of fuel cells having a fuel electrode flow path plate are laminated,
Two clamping plates for clamping the cell stack from both end sides in the stacking direction of the cell stack;
A connector for connecting the two fastening plates;
A self-adhesive thermal insulation part covering at least a part of the front surface and the back surface of the two clamping plates;
, A fuel cell. The two clamping plates have a hollow shape between the surface facing the cell stack and
The fuel cell according to claim 1, wherein the heat insulating material portion is filled in the hollow shape. The fuel cell further includes a manifold disposed on a side surface along the stacking direction of the cell stack and supplying a reaction gas to the fuel electrode channel plate in the cell stack or the oxidant electrode channel plate.
The fuel cell according to claim 1, wherein the heat insulator covers at least a part of the manifold. Current collectors disposed at both ends of the cell stack;
A terminal connected to the current collector plate,
The fuel cell according to any one of claims 1 to 3, wherein the heat insulating material portion covers a connection portion between a current cable connected to the terminal and the terminal.   The fuel cell according to any one of claims 1 to 4, wherein the heat insulating material portion is a blow-type foam heat insulating material. An electrolyte membrane, an oxidant electrode channel plate provided with an oxidant electrode channel facing the oxidant electrode of the electrolyte membrane, and a fuel electrode channel facing the fuel electrode of the electrolyte membrane are provided. And a step of connecting two clamping plates for clamping the cell stack from both end surfaces in the stacking direction of the cell stack to a cell stack in which a plurality of fuel cells having a fuel electrode flow path plate are stacked. When,
Spraying a self-adhesive insulation covering at least a portion of the front and back surfaces of the two clamping plates connected to the cell stack;
A method for assembling a fuel cell.