JP2018041656A - Fuel battery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fuel battery in which a stack is divided into electrically insulated regions by insulating parts, and which enables the reduction in the space of a fuel battery and the simplification of the structure thereof.SOLUTION: A fuel battery comprises a stack arranged by stacking single cells. The stack has insulating parts disposed along a lamination direction of the stack, and serving to divide the stack to form a plurality of electrically insulated reaction regions along a direction crossing the lamination direction. In an anode-side separator and a cathode-side separator, a first groove to form an anode gas passage and a second groove to form a cathode gas passage are formed in the plurality of reaction regions. The insulating parts in the anode-side separator and the cathode-side separator include: a first insulating part provided on an outer peripheral portion; and a second insulating part for division into the plurality of electrically insulated reaction regions. In the first insulating part, one of an inlet and outlet of each of the anode and cathode gas passages are provided. In the second insulating part, the other of the inlet and outlet is provided.SELECTED DRAWING: Figure 1

Description

  The present disclosure relates to fuel cells.

In a fuel cell, a single cell is composed of an electrolyte membrane, an electrode having a catalyst layer, a separator, and the like, and a plurality of single cells are stacked to form a stack. In a fuel cell, the output voltage is determined by the number of stacked single cells, and the output current is determined by the area of the reaction surface of each single cell.
In an automobile fuel cell that supplies power to only one or two motors without using many devices at the same time as a stationary fuel cell, the current value greatly affects the wire diameter and circuit resistance. Smaller is desirable. On the other hand, when the number of stacked single cells is large, the total length of the fuel cell becomes long and the mounting space becomes large.
Therefore, if the stack is divided and disposed, gas flow paths and wiring facilities are required for each, and the mounting space is not reduced.

  Patent Documents 1 and 2 disclose means for reducing the output current value without dividing the stack by forming a plurality of regions electrically insulated from the stack by an insulating portion.

JP 2003-282125 A JP 2011-216310 A

  In Patent Documents 1 and 2, when forming a plurality of regions that are electrically insulated from the stack by an insulating portion, in particular, means for reducing the space of the fuel cell, simplifying the configuration, and improving the reaction efficiency are disclosed. Not disclosed.

  Some embodiments have an object of enabling space saving and simplification of a configuration of a fuel cell in a fuel cell in which a stack is divided into a plurality of regions electrically insulated by an insulating portion.

  (1) A fuel cell according to some embodiments includes an electrolyte membrane, a membrane electrode assembly including an anode electrode disposed on one side of the electrolyte membrane and a cathode electrode disposed on the other side, and the membrane electrode An anode separator disposed so that an anode gas flow path is formed on the one side of the assembly, and a cathode separator disposed so that a cathode gas flow path is formed on the other side of the membrane electrode assembly; A fuel cell comprising a stack configured by stacking a plurality of single cells having the stack, the stack being disposed along the stacking direction of the single cells, and along the direction intersecting the stacking direction of the stack The anode-side separator and the cathode-side separator are connected to the anode in the plurality of reaction regions. A first groove for forming a gas flow path and a second groove for forming the cathode gas flow path are formed, and the insulating portion in the anode-side separator and the cathode-side separator is provided in an outer peripheral portion. A first insulating portion; and a second insulating portion that divides the reaction region into a plurality of electrically insulated regions. The first insulating portion has inlets for the anode gas channel and the cathode gas channel. Alternatively, one of the outlets is provided, and the other of the inlet and the outlet is provided in the second insulating portion.

According to the configuration of (1) above, by dividing the stack into a plurality of regions electrically insulated by the insulating portion, the reaction area of the stack in each region can be reduced, and the output current value can be reduced. By connecting these regions in series, high output voltage specifications can be achieved. Further, compared with the case where the stack is divided and arranged, the gas flow path and the wiring facility are not complicated, and space saving and simplification of the configuration can be achieved.
In addition, by providing the inlet and the outlet of the anode gas channel and the cathode gas channel in the first insulating part and the second insulating part, the area of the reaction region of the stack is not reduced by forming these gas channels, High reaction efficiency can be maintained.

  (2) In one embodiment, in the configuration of (1), the second insulating part is provided with the inlet of the anode gas channel and the cathode gas channel, and the anode of the first insulating part is the anode. The outlets of the anode gas channel and the cathode gas channel are provided in end side insulating regions formed at the left and right ends of the side separator and the cathode side separator.

  According to the configuration of (2) above, the anode gas flow channel and the cathode gas flow channel (hereinafter also referred to as “both gas flow channels” in the sense of including the above two gas flow channels. In the case of having two members having the same role on the cathode side, it is also referred to as “both” in the same meaning.) The inlet of the second insulating portion is provided, and the outlets of both gas flow paths are the ends of both separators. By providing in the side insulating region, both gas flow paths formed between both separators and both electrodes can be shortened. As a result, the pressure loss of the reaction gas flowing through both gas passages can be reduced, the reaction efficiency can be maintained high, and the discharge performance of the produced water can be improved.

(3) In one embodiment, in the configuration of (1) or (2), the plurality of reaction regions are two reaction regions that are electrically insulated left and right by the second insulating portion and have an equal reaction area. Consists of.
According to the configuration of (3) above, the reaction area of the stack can be divided into two electrically insulated left and right areas, so that the size and shape can be adapted to the mounting space provided in the automobile. In addition, by making the reaction areas of the two regions equal, the current values generated in both regions become equal, so the control of the output current value of the fuel cell is facilitated.

(4) In one embodiment, in the configuration of (2) or (3), an inlet and an outlet of the cooling water flow path are provided in the end-side insulating region.
According to the configuration of (4) above, since the inlet and outlet of the cooling water channel are provided in the end insulating regions of both separators, the formation of the cooling water channel does not reduce the area of the reaction region of the stack. The reaction efficiency can be kept high.

(5) In an embodiment, in any one of the configurations (1) to (4), the first insulating portion and the second insulating portion are configured by a frame body having a fitting groove on an inner periphery,
The reaction region is formed of a plate-like body having the first groove and the second groove formed on the front and back surfaces, and an outer peripheral edge fitted into the fitting groove and attached to the frame body.
According to the configuration of (5) above, both separators can be easily manufactured, processed, and assembled into a single cell.

(6) In one embodiment, in the configurations of (1) to (5), the first groove and the second groove have a rectangular cross section.
According to the configuration of (6) above, since the first groove and the second groove have a rectangular cross section, the gas permeation area of the gas diffusion layer can be increased, whereby the amount of permeate gas can be increased. Can be improved.

  According to some embodiments, the stack can be divided into a plurality of regions electrically insulated by the insulating portion without causing an increase in gas flow paths and wiring facilities. Therefore, it is possible to save the space and simplify the configuration of the fuel cell.

1 is a perspective view of a fuel cell according to an embodiment. It is a perspective view which expands and shows a single cell concerning one embodiment. It is a perspective view which shows the electrode and separator on the anode side which concern on one Embodiment. It is a perspective view which shows the electrode and separator on the cathode side which concern on one Embodiment. It is a perspective view of the separator which concerns on one Embodiment. It is sectional drawing which follows the AA line in FIG. It is sectional drawing which follows the BB line in FIG.

Several embodiments of the present invention will be described below with reference to the accompanying drawings. However, the dimensions, materials, shapes, and relative arrangements of the components described in these embodiments or shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative examples. Only.
For example, expressions expressing relative or absolute arrangements such as “in a certain direction”, “along a certain direction”, “parallel”, “orthogonal”, “center”, “concentric” or “coaxial” are strictly In addition to such an arrangement, it is also possible to represent a state of relative displacement with an angle or a distance such that tolerance or the same function can be obtained.
For example, an expression indicating that things such as “identical”, “equal”, and “homogeneous” are in an equal state not only represents an exactly equal state, but also has a tolerance or a difference that can provide the same function. It also represents the existing state.
For example, expressions representing shapes such as quadrangular shapes and cylindrical shapes represent not only geometrically strict shapes such as quadrangular shapes and cylindrical shapes, but also irregularities and chamfers as long as the same effects can be obtained. A shape including a part or the like is also expressed.
On the other hand, the expressions “comprising”, “comprising”, “comprising”, “including”, or “having” one constituent element are not exclusive expressions for excluding the existence of other constituent elements.

  As shown in FIG. 1, the fuel cell 10 according to some embodiments includes a stack 12 in which a plurality of single cells 14 are stacked in one direction. In the illustrated embodiment, end plates 50 are provided on both sides of the stack 12. The end plate 50 includes a fuel gas pipe 52 and an air pipe 54 that supply hydrogen or air as a reaction gas to each single cell 14, and cooling water. Is provided to the stack 12.

As shown in FIG. 2, the single cell 14 includes an electrolyte membrane 16, a membrane electrode assembly 21 including an anode electrode 18 disposed on one side of the electrolyte membrane 16 and a cathode electrode 20 disposed on the other side, and an anode electrode. The anode side separator 22 disposed on the outer side (one side) 18 and the cathode side separator 24 disposed on the outer side (the other side) of the cathode electrode 20 are overlapped.
In one embodiment, power generation of 0.5 to 1.0 V per unit cell is performed, and power generation of several hundred V is performed in the entire stack.

The stack 12 has an insulating portion 30 (30a, 30b, 30c, 30d, 30e) arranged along the stacking direction of the single cells 14 (the direction of arrow a in FIG. 1). Stack 12 is divided into a plurality of regions R ₁ and R ₂ along the direction crossing the stacking direction by the insulating portion 30, a plurality of regions R ₁ and R ₂ each electrically insulated plurality of reaction regions 17a and 17b are formed. Hydrogen ions are generated in the reaction region of the anode electrode 18, and the hydrogen ions are transmitted from the anode electrode 18 toward the cathode electrode 20.

FIG. 3 shows an anode separator 22 and an anode electrode 18 according to an embodiment. FIG. 4 shows a cathode electrode 20 and a cathode-side separator 24 according to one embodiment. FIG. 5 shows an embodiment of a separator used as the anode side separator 22 or the cathode side separator 24.
As shown in FIG. 3, an anode gas flow path 26 is formed between the anode electrode 18 and the anode side separator 22, and the cathode gas is interposed between the cathode electrode 20 and the cathode side separator 24 as shown in FIG. 4. A flow path 28 is formed.

As shown in FIGS. 3 and 5, the anode separator 22 forms the anode gas flow path 26 in the reaction regions 17 a and 17 b formed in the plurality of regions R ₁ and R ₂ divided by the insulating part 30. A first groove 32 is formed.
As shown in FIGS. 4 and 5, the cathode side separator 24, the second groove 34 to form a cathode gas channel 28 into a plurality of regions R ₁ and reaction regions 17a and 17b of each R ₂ is formed The

  In both separators 22 and 24, the insulating portions 30 (30d, 30e) shown in FIG. 1 are schematically shown, and more precisely, as shown in FIG. The first insulating portion 36 and the second insulating portion 38 that divides the reaction region into a plurality of electrically insulated reaction regions 17a and 17b. One of the inlets 40 and 42 or the outlets 44 (44a and 44b) and 46 (46a and 46b) of the anode gas passage 26 and the cathode gas passage 28 is provided in the first insulating portion 36, and the second insulating portion 38 The other of the inlet or the outlet is provided.

According to the above configuration, the reaction area of the stack 12 is divided into the plurality of reaction areas 17a and 17b that are electrically insulated by the insulating unit 30, thereby reducing the reaction area of each reaction area, and thereby the output current. The value can be reduced. Moreover, the specification of a high output voltage is realizable by connecting the divided | segmented several reaction area | region in series. Further, compared with the case where the stack 12 is divided and disposed, the gas flow path and the wiring facility are not complicated, and the space saving and the simplification of the configuration of the fuel cell 10 can be achieved.
Further, by providing the first insulating portion 36 and the second insulating portion 38 with the inlets 40 and 42 and the outlets 44 and 46 of the anode gas channel 26 and the cathode gas channel 28, the reaction region 17a is formed by forming these gas channels. And the reaction area of 17b is not reduced, so that the reaction efficiency can be kept high.

In one embodiment, the anode electrode 18 and the cathode electrode 20 are composed of a catalyst layer that is disposed on the electrolyte membrane 16 side and promotes a reaction in each electrode, and a gas diffusion layer that has a property of allowing the reaction gas to permeate. Is done.
Moreover, the said gas diffusion layer is manufactured by methods, such as press molding, using carbon fiber as a material, for example. Further, since both the separators 22 and 24 are made of a metal separator that is usually easy to process, groove processing is easy.

  In one embodiment, as shown in FIG. 5, the second insulating portion 38 is provided with an inlet 40 of the anode gas channel 26 and an inlet 42 of the cathode gas channel 28. In the first insulating portion 36, the anode gas passage 26 outlet 44 (44a, 44b) and the outlet of the cathode gas passage 28 are connected to the end-side insulating regions 48a and 48b formed at the left and right ends of the separators 22 and 24, respectively. 46 (46a, 46b) is provided.

  According to the above configuration, the inlets 40 and 42 of both the gas flow paths 26 and 28 are provided in the second insulating portion 38 provided at the intermediate position between the end-side insulating regions 48a and 48b, and the outlets of both the gas flow paths are provided as both separators. By providing in the end side insulating regions 48a and 48b of 22 and 24, both gas flow paths 26 and 28 formed between both separators 22 and 24 and both electrodes 18 and 20 can be shortened. As a result, the pressure loss of the reaction gas flowing through both the gas flow paths 26 and 28 can be reduced, the reaction efficiency can be improved, and the performance of discharging generated water can be improved.

  In one embodiment, as shown in FIG. 5, since the first groove 32 and the second groove 34 extend in the lateral direction, the end-side insulating region extends from the inlets 40 and 42 provided in the second insulating portion 38. The reaction gas can be easily guided to the outlets 44 and 46 provided at 48a and 48b, and the pressure loss can be further reduced.

In one embodiment, as shown in FIG. 5, the plurality of reaction regions 17 a and 17 b are configured by two reaction regions that are electrically insulated left and right by the second insulating portion 38 and have an equal reaction area.
According to the said structure, it can be set as the magnitude | size and shape suitable for the mounting space provided in a motor vehicle by dividing | segmenting the reaction area | region of the stack 12 into two electrically insulated right and left area | regions. In addition, by equalizing the reaction areas of the two reaction regions 17a and 17b, the current values generated in both regions become equal, and thus the output current value of the fuel cell 10 can be easily controlled.

In one embodiment, as shown in FIG. 5, the end side insulating regions 48a and 48b of both separators 22 and 24 are provided with inlets 60a and 60b and outlets 62a and 62b of the cooling water flow path.
According to the above configuration, the inlets 60a and 60b and the outlets 62a and 62b of the cooling water channel are provided in the end-side insulating regions 48a and 48b of the separators 22 and 24. Therefore, the reaction region 17a of the stack 12 is formed by forming the cooling water channel. And the area of 17b is not reduced, so that a decrease in reaction efficiency can be prevented and the reaction efficiency can be maintained high.

In one embodiment, as shown in FIG. 6, the first insulating portion 36 and the second insulating portion 38 are configured by a frame body 66 having a fitting groove 64 on the inner peripheral edge, and the reaction regions 17a and 17b are formed on the front and back surfaces. The first groove 32 and the second groove 34 are formed, and the outer peripheral edge is formed by a plate-like body 67 that is fitted into the fitting groove 64 and is attached to the frame body 66.
According to the said structure, manufacture of both the separators 22 and 24, a process, and the assembly | attachment to the single cell 14 become easy.
In one embodiment, as a method of attaching the plate-like body 67 to the frame body 66, the frame body 66 is formed of two divided plates in the thickness direction, and the plate-like body 67 is formed by these two divided plates. Glue and fix with pinching from both sides.

In one embodiment, as shown in FIG. 5, the separators used for both separators 22 and 24 are formed such that an anode gas channel 26 and a cathode gas channel 28 can be formed on the front and back surfaces. That is, the first insulating portion 36 and the second insulation between the inlet 40 and outlet 44 (44a, 44b) of the anode gas flow path 26 and the first groove 32 are provided on the back surface (the surface on the back side with respect to the paper surface). On the surface of the portion 38, a recessed channel having a step 68 with respect to the other surface is formed, and the anode gas passes from the inlet 40 through the recessed channel and the first groove 32 to the outlet 44 (44a, 44b). ).
When used as the anode separator 22, weirs 72 are formed around the inlets and outlets of other flow paths on the back surface, and fluid other than the anode gas flows between the anode separator 22 and the anode electrode 18. It is supposed not to.

Similarly, on the surface of the cathode-side separator 24 (the surface on the front side with respect to the paper surface), there are other gaps between the inlet 42 and the outlet 46 (46a, 46b) of the cathode gas channel 28 and the second groove 34. A recessed channel having a step 70 with respect to the surface is formed, and the cathode gas flows from the inlet 42 through the recessed channel and the second groove 34 to the outlet 46 (46a, 46b).
When used as the cathode-side separator 24, weirs 72 are formed around the inlets and outlets of other flow paths on the surface, and fluid other than the cathode gas flows between the cathode-side separator 24 and the cathode electrode 20. It is supposed not to.
In this way, the anode gas channel 26 and the cathode gas channel 28 are simply processed by processing the first groove 32, the second groove 34, the steps 68 and 70, and the weir 72 on the front and back surfaces of the plate-shaped separator plate. Therefore, piping for forming both gas flow paths is not required.

In one embodiment, as shown in FIG. 7, the first groove 32 and the second groove 34 formed in the reaction regions 17a and 17b have a rectangular cross section. According to the above configuration, since the first groove 32 and the second groove 34 have a rectangular cross section, the reaction area is increased by the amount of the side wall 74 compared to a flat electrode.
As a result, the gas permeation areas of the anode electrode 18 and the cathode electrode 20 can be increased, and the amount of permeated gas can be increased, thereby improving the reaction efficiency.
FIG. 7 shows a state where the anode gas Ga passes through the side wall 74.

  In the embodiment shown in FIGS. 1 to 5, the reaction regions 17 a and 17 b of the stack 12 are divided into left and right by the insulating portion 30. However, in another embodiment, the reaction region is divided into three or more. May be.

  According to some embodiments, in the fuel cell in which the stack is divided into a plurality of regions electrically insulated by the insulating portion, it is possible to save the space and simplify the configuration of the fuel cell. Therefore, the fuel cell can be reduced in size, and the shape can be easily adjusted to, for example, the mounting space of an automobile.

DESCRIPTION OF SYMBOLS 10 Fuel cell 12 Stack 14 Single cell 16 Electrolyte membrane 17a, 17b Reaction area | region 18 Anode electrode 20 Cathode electrode 21 Membrane electrode assembly 22 Anode side separator 24 Cathode side separator 26 Anode gas flow path 28 Cathode gas flow path 30 (30a, 30b 30c, 30d, 30e) Insulating part 32, 34 Groove 36 First insulating part 38 Second insulating part 40, 42, 60a, 60b Inlet 44 (44a, 44b), 46 (46a, 46b), 62a, 62b Outlet 48a 48b End side insulating region 50 End plate 52 Fuel gas pipe 54 Air pipe 56 Cooling water pipe 64 Fitting groove 66 Frame body 67 Plate-like body 68, 70 Step 72 Weir 74 Side wall Ga anode gas

Claims (6)

An electrolyte membrane;
A membrane electrode assembly comprising an anode electrode disposed on one side of the electrolyte membrane and a cathode electrode disposed on the other side;
An anode side separator disposed so that an anode gas flow path is formed on the one side of the membrane electrode assembly;
A cathode side separator disposed so that a cathode gas flow path is formed on the other side of the membrane electrode assembly;
A fuel cell comprising a stack formed by stacking a plurality of single cells having
The stack has an insulating part that is arranged along a stacking direction of the single cells and forms a plurality of reaction regions electrically insulated along a direction intersecting the stacking direction in the stack.
The anode-side separator and the cathode-side separator are formed with a first groove for forming the anode gas flow path and a second groove for forming the cathode gas flow path in the plurality of reaction regions,
The insulating portions in the anode-side separator and the cathode-side separator have a first insulating portion provided on an outer peripheral portion and a second insulating portion that divides the reaction region into a plurality of electrically insulated regions. And
One of the inlet and the outlet of the anode gas channel and the cathode gas channel is provided in the first insulating portion, and the other of the inlet and the outlet is provided in the second insulating portion. . The second insulating part is provided with the inlet of the anode gas channel and the cathode gas channel;
The outlet of the anode gas channel and the cathode gas channel is provided in end-side insulating regions formed at the left and right ends of the anode-side separator and the cathode-side separator in the first insulating part. The fuel cell according to claim 1.   3. The fuel cell according to claim 1, wherein the plurality of reaction regions include two reaction regions that are electrically insulated from each other right and left by the second insulating portion and have an equal reaction area.   4. The fuel cell according to claim 2, wherein an inlet and an outlet of a cooling water channel are provided in the end-side insulating region. The first insulating portion and the second insulating portion are configured by a frame having a fitting groove on an inner peripheral edge,
2. The reaction region is configured by a plate-like body having the groove formed on the front and back surfaces and having an outer peripheral edge fitted into the fitting groove and attached to the frame body. The fuel cell according to any one of 1 to 4.   The fuel cell according to any one of claims 1 to 5, wherein the first groove and the second groove have a rectangular cross section.

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