Separators, electrochemical cells, stacks, and apparatus

Abstract

The embodiment provides a separator that is less prone to gas accumulation. [Solution] The separator of the embodiment includes a plurality of flow channel grooves and has a first flow channel connecting a first point and a second point. The first flow channel has a serpentine flow channel shape. The midpoint in the longitudinal direction of the first flow channel is defined as the boundary, the part from the boundary toward the first point is the first half of the first flow channel, and the part from the boundary toward the second point is the second half of the first flow channel. The first half of the first flow channel includes a folded portion of the first flow channel, and the second half of the first flow channel includes a folded portion having a flow channel pattern different from the flow channel pattern of the folded portion in the first half of the first flow channel.

Description

Technical Field

[0001] Embodiments of the present invention relate to separators, electrochemical cells, stacks, and devices.

Background Art

[0002] In recent years, expectations for renewable energy have been increasing. Examples of renewable energy include solar power generation, hydropower generation, wind power generation, geothermal power generation, and the like.

[0003] Furthermore, as attempts towards decarbonization, power generation by fuel cells and energy conversion by electrolysis have attracted attention.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Non-Patent Documents

[0005]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] Embodiments provide a separator in which gas is less likely to accumulate.

Means for Solving the Problems

[0007] The separator of the embodiment includes a plurality of flow channel grooves and has a first flow channel connecting a first point and a second point. The first flow channel has a serpentine flow channel shape. The midpoint in the longitudinal direction of the first flow channel is defined as the boundary, the part from the boundary toward the first point is the first half of the first flow channel, and the part from the boundary toward the second point is the second half of the first flow channel. The first half of the first flow channel includes a folded portion of the first flow channel, and the second half of the first flow channel includes a folded portion having a flow channel pattern different from the flow channel pattern of the folded portion in the first half of the first flow channel. [Brief explanation of the drawing]

[0008] [Figure 1] A schematic diagram of the separator in the embodiment. [Figure 2] A schematic cross-sectional view of the separator in the embodiment. [Figure 3] A schematic cross-sectional view of the separator in the embodiment. [Figure 4] A schematic diagram of the separator in the embodiment. [Figure 5] A schematic diagram of the separator in the embodiment. [Figure 6] A schematic diagram of the separator in the embodiment. [Figure 7] A schematic diagram of the separator in the embodiment. [Figure 8] A schematic diagram of the separator in the embodiment. [Figure 9] A schematic diagram of the separator in the embodiment. [Figure 10] A schematic diagram of the separator in the embodiment. [Figure 11] A schematic diagram of the separator in the embodiment. [Figure 12] A schematic diagram of the separator in the embodiment. [Figure 13] A schematic diagram of the separator in the embodiment. [Figure 14] A schematic diagram of the separator in the embodiment. [Figure 15] Schematic diagram of an electrochemical cell according to an embodiment. [Figure 16] Schematic diagram of an electrochemical cell according to an embodiment. [Figure 17] A schematic diagram of the stack in the embodiment. [Figure 18]Schematic diagram of the device according to the embodiment. [Figure 19] Schematic diagram of the device according to the embodiment.

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following description, the same reference numerals are assigned to the same members and the description of the members once described will be omitted as appropriate.

[0010] The physical property values in the specification are values at a temperature of 25 [°C] and a pressure of 1 [atm]. The thickness of each member is the average value of the distances in the stacking direction.

[0011] (First Embodiment) The first embodiment relates to the separator 100. FIG. 1 shows a schematic diagram of the separator 100 according to the embodiment. FIG. 2 shows a schematic cross-sectional view taken along the line A-A' in FIG. 1. FIG. 3 shows a schematic cross-sectional view taken along the line B-B' in FIG. 1. The separator 100 has a first flow path 10, a supply manifold 4, a discharge manifold 6, a supply connection path 3, and a discharge connection path 5. The first flow path 10, the supply manifold 4, the discharge manifold 6, the supply connection path 3, and the discharge connection path 5 are provided in the frame 7 of the separator 100. The directions in the figure are represented by X, Y, and Z.

[0012] The separator 100 of the first embodiment is used, for example, in an electrochemical cell for a fuel cell or electrolysis. The separator 100 supplies a fluid used in the reaction of the electrode and discharges a fluid containing the product of the reaction of the electrode. The fluid is a gas and / or a liquid. When the fluid discharged from the discharge manifold 6 contains both a gas and a liquid, the pressure loss of the separator 100 can be effectively suppressed.

[0013] The separator 100 has a first flow path 10 including a flow path wall 1 and a flow path groove 2 provided between the flow path walls 1. The flow path wall 1 may surround the supply manifold 4, the discharge manifold 6, the supply connection path 3, and the discharge connection path 5.

[0014] The region sandwiched between the flow channel walls 1 is the flow channel groove 2. The flow channel walls 1 may be, for example, a protrusion of a metal member provided on the frame 7, or the flow channel groove 2 may be a recess of a metal member provided on the frame 7. Fluid flows through the first flow channel 10. The first flow channel 10 has a plurality of flow channel grooves 2, and it is preferable that the fluid flows through the plurality of flow channel grooves 2. In order for the fluid to flow through the entire porous layer of the electrode that is in contact with the separator 100 with minimal separation, it is preferable that the first flow channel 10 has a serpentine flow channel shape in which straight sections and folded sections are alternately repeated, as shown in the schematic diagram of Figure 1.

[0015] The first channel 10, which has a serpentine channel shape, has a straight section and a bent section T connecting the straight sections. In the bent section T, the channel is bent or curved such that the fluid flowing in the straight section flows in the opposite direction.

[0016] A folded section T is a section that changes the direction of fluid flow by 180° (or approximately 180°). The first flow path 10 in Figure 1 includes four folded sections. The first flow path 10 in Figure 1 includes the first folded section T1, the second folded section T2, the third folded section T3, and the fourth folded section T4.

[0017] The portion where the channel groove 2 bends at 90° at the connection point between the first channel 10 and the supply communication channel 3 is not included in the bent portion, because the first channel 10 and the supply communication channel 3 can also be connected without the channel groove 2 bending.

[0018] The portion where the flow channel groove 2 bends at 90° at the connection point between the first flow channel 10 and the discharge communication channel 5 is not included in the bent portion, because the first flow channel 10 and the discharge communication channel 5 can also be connected without the flow channel groove 2 bending.

[0019] For example, if the number of folded sections T is odd, the boundary between the first and second halves of the flow channel groove 2 may lie within a folded section. In this case, one folded section contains both the first and second halves of the flow channel groove 2.

[0020] The channel wall 1 is made of, for example, metal.

[0021] The first channel 10 has multiple channel grooves 2. The first channel 10 has a first channel wall 1A, a first channel groove 2A, a second channel wall 1B, a second channel groove 2B, a third channel wall 1C, a third channel groove 2C, a fourth channel wall 1D, a fourth channel groove 2D, and a fifth channel wall 1E. The numbers of the channel walls 1 and channel grooves 2 are for convenience only, and in some cases they may not be in numerical order. If the order in which the channel grooves 2 are arranged is different (for example, in the order of first channel groove 2A, fourth channel groove 2D, third channel groove 2C, second channel groove 2B), the numbers of the channel walls 1 flanking each channel groove 2 will change. In the separator 100, the channel grooves 2 are numbered starting from the channel grooves 2 that are connected to each other. The following explanation of channel grooves 2 is not limited to any specific channel groove 2.

[0022] In this embodiment, four flow channel grooves 2 are shown, but the number of flow channel grooves 2 is not limited to four, and can be one or more. For example, separators with three flow channel grooves 2, separators with five flow channel grooves 2, and separators with eight flow channel grooves 2 are also included in the separators of this embodiment.

[0023] The first channel groove 2A is located between the channel walls. In the schematic diagram of Figure 1, the first channel groove 2A is located between the first channel wall 1A and the second channel wall 1B.

[0024] The second channel groove 2B is located between the channel walls. In the schematic diagram of Figure 1, the second channel groove 2B is located between the first channel wall 1A and the third channel wall 1C.

[0025] The third channel groove 2C is located between the channel walls. In the schematic diagram of Figure 1, the third channel groove 2C is located between the third channel wall 1C and the fourth channel wall 1D.

[0026] The fourth channel groove 2D is located between the channel walls. In the schematic diagram of Figure 1, the fourth channel groove 2D is located between the fourth channel wall 1D and the fifth channel wall 1E.

[0027] The pitch of the flow channel groove 2 is preferably, for example, 0.1 mm or more and 5 mm or less, more preferably 0.3 mm or more and 3 mm or less, and even more preferably 0.5 mm or more and 2.5 mm or less.

[0028] The supply communication passage 3 is provided between the supply manifold 4 and the first flow path 10. The supply communication passage 3 is a flow path that connects the supply manifold 4 and the first flow path 10. The fluid that passes through the supply communication passage 3 flows through the first flow path 10. The supply communication passage 3 may be the irregularities of the frame 7, or it may be composed of a separate component from the frame 7. The fluid also flows in the direction in which the supply communication passage 3 and the supply manifold 4 connect.

[0029] The supply manifold 4 is the opening of the separator 100. Fluid is supplied from the supply manifold 4. The separator 100 may be provided with other manifolds, which are not shown.

[0030] In the first embodiment, the supply communication path 3 and supply manifold 4 of the separator 100 are provided on the side of the first point P1.

[0031] The discharge connecting passage 5 is provided between the discharge manifold 6 and the first flow path 10. The discharge connecting passage 5 is a flow path that connects the discharge manifold 6 and the first flow path 10. The fluid that has passed through the first flow path 10 and then the discharge connecting passage 5 is discharged from the discharge manifold 6. The discharge connecting passage 5 may be made up of the irregularities of the frame 7, or it may be made up of a separate component from the frame 7.

[0032] The discharge manifold 6 is the opening of the separator 100. Fluid is discharged from the discharge manifold 6.

[0033] In the first embodiment, the fluid passing through the first channel 10 flows from the first point P1 toward the second point P2.

[0034] In the first embodiment, the discharge communication passage 5 and discharge manifold 6 of the separator 100 are provided on the side of the first point P1.

[0035] The frame 7 is preferably made of an insulating material, such as a resin material.

[0036] The boundary is defined as the midpoint along the length of the first channel 10. In Figure 1, the boundary is represented by a virtual line G. The length of the first channel 10 is the length of the center of the channel pattern of the first channel 10. In the case of the separator 100 in Figure 1, the length of the channel pattern from the first point P1 to the second point P2 on the third channel wall 1C is the length of the first channel 10. Since the fluid containing the fluid used in the electrode reaction and the products flows from the first point P1 to the second point P2 in the first channel 10, the first half of the first channel 10 is defined as the section from the boundary G of the channel through which the fluid flows to the first point P1, and the second half of the first channel 10 is defined as the section from the boundary G to the second point P2.

[0037] It is preferable that the separator 100 includes a folded portion T in the latter half of the first flow path 10 that has a flow path pattern different from the flow path pattern of the folded portion T in the first half of the first flow path 10. This can suppress the accumulation of gas contained in the fluid, including liquids and gases, flowing through the first flow path 10 in the flow path groove 2.

[0038] The cross-sections A-A' in Figure 2 and B-B' in Figure 3 show the cross-sections of the first folded portion T1 and the fourth folded portion T4, respectively. The fourth folded portion T4 has a connecting groove J enclosed by a dashed line, which is not present in the first folded portion T1. As shown in the schematic cross-sectional diagrams of Figures 2 and 3, the first flow path 10 has different flow path patterns in the first half and the second half of the folded portion T.

[0039] If gas accumulates in the flow channel groove 2, the gas generated at the electrode in contact with the separator 100 is likely to undergo a side reaction. When CO2 is electrolyzed, oxygen gas, which is generated at the cathode and has a high concentration on the anode discharge side, reacts with hydrogen gas, which is reduced in concentration by the electrolysis of CO2 on the cathode discharge side and reduces water through a side reaction, producing hydrogen peroxide. Since hydrogen peroxide degrades the electrolyte membrane, it is preferable to connect only a portion of the flow channel groove 2 to prevent gas accumulation. Connecting the flow channel groove 2 at all the folded parts of the serpentine-shaped flow channel, or connecting the flow channel groove 2 in the first half of the first flow channel 10 of the serpentine-shaped flow channel, is not effective. By connecting a portion of the flow channel groove 2 in the latter half, rather than the first half, of the first flow channel 10 of the serpentine-shaped flow channel, gas accumulation can be suppressed.

[0040] Some of the multiple flow grooves 2 in the latter half of the first flow path 10 are connected and / or some of the flow grooves 2 in the latter half of the first flow path 10 are closed, while the multiple flow grooves 2 in the first half of the first flow path 10 are not connected and some of the flow grooves 2 in the first half of the first flow path 10 are not closed, so that the latter half of the first flow path 10 includes a folded portion T having a flow pattern different from the flow pattern of the folded portion T in the first half of the first flow path 10. Some of the flow grooves 2 in the latter half of the first flow path 10 are connected by connecting grooves J.

[0041] In the separator 100 shown in Figure 1, the first flow channel groove 2A and the second flow channel groove 2B are connected at the fourth folded portion T4. The first flow channel wall 1A flanking the first flow channel groove 2A is partially interrupted, and the third flow channel wall 1C flanking the second flow channel groove 2B is partially interrupted, thereby connecting the first flow channel groove 2A and the second flow channel groove 2B. The first flow channel groove 2A and the second flow channel groove 2B are connected at the first connecting groove J1.

[0042] The first connecting groove J1 is preferably located in the latter half of the first flow path 10, and more preferably in the folded portion T of the latter half of the first flow path 10 (in the separator 100 in Figure 1, the third folded portion T3 and / or the fourth folded portion T4).

[0043] It is preferable that the first channel wall 1A flanking the first channel groove 2A is partially interrupted, and that the length of the first channel wall 1A in the latter half of the first channel 10 is shorter than the length of the first channel wall 1A in the first half of the first channel 10.

[0044] The schematic diagram in Figure 1 shows the length L1 of the first channel groove 2A of the fourth folded portion T4, the length L2 of the second channel groove 2B of the fourth folded portion T4, the length L3 of the third channel groove 2C of the fourth folded portion T4, and the length L4 of the fourth channel groove 2D of the fourth folded portion T4.

[0045] The length at which the first channel groove 2A and the second channel groove 2B are connected (the length at which the first channel groove 2A and the second channel groove 2B are connected in one folded portion T) is preferably 7% to 100% of the length L1 of the first channel groove 2A in the folded portion where the first channel groove 2A is connected to the second channel groove 2B, more preferably 50% to 100%, and even more preferably 70% to 100%.

[0046] When the second channel groove 2B and the third channel groove 2C are connected, the length of the connection between the second channel groove 2B and the third channel groove 2C (the length of the connection between the second channel groove 2B and the third channel groove 2C at one folded portion T) is preferably 9% to 100% of the length L2 of the second channel groove 2B at the folded portion where the second channel groove 2B and the third channel groove 2C are connected, more preferably 50% to 100%, and even more preferably 70% to 100%.

[0047] When the third channel groove 2C and the fourth channel groove 2D are connected, the length of the connection between the third channel groove 2C and the fourth channel groove 2D (the length of the connection between the third channel groove 2C and the fourth channel groove 2D at one folded portion T) is preferably 14% to 100% of the length L3 of the third channel groove 2C at the folded portion where the third channel groove 2C and the fourth channel groove 2D are connected, more preferably 50% to 100%, and even more preferably 70% to 100%.

[0048] When a connecting groove J is provided between the second channel groove 2B and the third channel groove 2C, the third channel wall 1C located between the second channel groove 2B and the third channel groove 2C is interrupted, and the second connecting groove J2, located in the portion where the third channel wall 1C is interrupted, connects the second channel groove 2B and the third channel groove 2C.

[0049] When a connecting groove J is provided between the third channel groove 2C and the fourth channel groove 2D, the fourth channel wall 1D located between the third channel groove 2C and the fourth channel groove 2D is interrupted, and the third connecting groove J3, located in the interrupted portion of the fourth channel wall 1D, connects the third channel groove 2C and the fourth channel groove 2D.

[0050] When the first flow path 10 includes multiple flow path grooves 2, it is preferable that the multiple flow path grooves 2 are parallel. It is preferable that the connecting groove J extends perpendicular to the direction in which the flow path grooves 2 are aligned and connects the flow path grooves 2. It is preferable that the connecting groove J extends perpendicular to the straight portion of the flow path groove 2 and connects the flow path grooves 2.

[0051] The connection of the flow channel groove 2 will be further explained below, using multiple examples of separators 100.

[0052] Figure 4 shows a schematic diagram of separator 101. Separator 101 shown in Figure 4 is a modified example of separator 100. The flow path patterns of the third folded portion T3 and the fourth folded portion T4 of separator 101 are different from the flow path patterns of the first folded portion T1 and the second folded portion T2.

[0053] The separator 101 shown in Figure 4 has a break in the flow channel wall 1 that extends perpendicular to the extension direction Y of the straight portions of the third folded portion T3 and the fourth folded portion T4. The first flow channel groove 2A and the second flow channel groove 2B are connected by the first connecting groove J1. The second flow channel groove 2B and the third flow channel groove 2C are connected by the second connecting groove J2. The third flow channel groove 2C and the fourth flow channel groove 2D are connected by the third connecting groove J3. The first connecting groove J1, the second connecting groove J2, and the third connecting groove J3 are provided in both the third folded portion T3 and the fourth folded portion T4.

[0054] In the latter half of the first channel 10, at the folded-back portion T, the channel wall 1 is partially interrupted, and the portion where all the channel grooves 2 included in the latter half of the first channel 10 are connected is included in the first channel 10.

[0055] In the separator 101, the flow path groove 2 connects in the latter half of the first flow path 10, causing a change in the fluid flow ease at the return section T. Because the fluid flow ease changes between the first and second halves of the first flow path 10, gas is less likely to accumulate in the latter half of the first flow path 10.

[0056] Figure 5 shows a schematic diagram of separator 102. Separator 102 shown in Figure 5 is a modified example of separator 101. In separator 102, the third folded portion T3 in the latter half of the first flow path 10 has the same flow path pattern as the first folded portion T1 and the second folded portion T2 in the first half of the first flow path 10, and a first columnar wall K1 connected to the second flow path wall 1B is provided in the fourth folded portion T4.

[0057] The columnar wall K is provided on the flow channel groove 2 and / or on the connecting groove J. Preferably, the columnar wall K does not divide the area where the flow channel groove 2 is connected by the connecting groove J. The flow channel pattern also changes due to the columnar wall K. Preferably, the columnar wall K is provided in the latter half of the first flow channel 10. The columnar wall K has a prism or cylindrical shape. Preferably, the columnar wall K is made of, for example, metal and / or resin. Preferably, the columnar wall K has a height similar to that of the flow channel wall 1.

[0058] In the separator 102, the flow channel groove 2 is connected at the fourth return section T4 in the latter half of the first flow channel 10, and the presence of a columnar wall K further alters the fluid flow ease at the return section T. Because the fluid flow ease changes between the first and second halves of the first flow channel 10, gas is less likely to accumulate in the latter half of the first flow channel 10.

[0059] Figure 6 shows a schematic diagram of separator 103. Separator 103 shown in Figure 6 is a modified example of separator 102. Separator 103 has island-shaped first columnar walls K1, island-shaped second columnar walls K2, and island-shaped third columnar walls K3, which are provided in the area of ​​the wide flow channel groove 2 where the flow channel wall 1 of the fourth folded portion T4 is interrupted. The columnar walls K may be in contact with the flow channel wall 1, or they may not be in contact with the flow channel wall 1 (island-shaped).

[0060] In the separator 103, the flow channel groove 2 is connected at the fourth return section T4 in the latter half of the first flow channel 10, and the presence of a columnar wall K further alters the fluid flow ease at the return section T. Because the fluid flow ease changes between the first and second halves of the first flow channel 10, gas is less likely to accumulate in the latter half of the first flow channel 10.

[0061] Figure 7 shows a schematic diagram of separator 104. Separator 104 shown in Figure 7 is a modified example of separator 101. In separator 104, a wider area of ​​the flow path wall 1 is removed at the third and fourth folded portions T3 and T4 than in separator 101, and the first flow path 10 has different flow path patterns in the first and second halves. The U-shaped flow path wall 1 is removed at the third and fourth folded portions T3 and T4, and a first connecting groove J1, a second connecting groove J2 and a third connecting groove J3 are provided.

[0062] In the latter half of the first channel 10, many channel walls 1 have been removed. It is preferable that some channel walls 1 remain in the latter half of the first channel 10. The total length of the channel walls 1 in the latter half of the first channel 10 is preferably 20% to 98% of the total length of the channel walls 1 in the first half of the first channel 10, more preferably 29% to 80%, and even more preferably 39% to 61%.

[0063] In the separator 104, the flow path groove 2 connects in the latter half of the first flow path 10, causing a change in the fluid flowability at the return section T. Because the fluid flowability changes between the first and second halves of the first flow path 10, gas is less likely to accumulate in the latter half of the first flow path 10.

[0064] Figure 8 shows a schematic diagram of separator 105. Separator 105 shown in Figure 8 is a modified example of separator 104. In separator 105, the first channel wall 1A, third channel wall 1C, and fourth channel wall 1D are interrupted in portions other than the folded portion T. The channel wall 1 may be interrupted in portions other than the folded portion T, but it is preferable that the channel wall 1 located on the inner circumference side of the channel groove 2 located furthest in the folded portion T is not interrupted, although it may be shortened in the latter half of the first channel 10.

[0065] In the separator 105, the flow path groove 2 connects in the latter half of the first flow path 10, causing a change in the fluid flowability at the return section T. Because the fluid flowability changes between the first and second halves of the first flow path 10, gas is less likely to accumulate in the latter half of the first flow path 10.

[0066] Figure 9 shows a schematic diagram of separator 106. Separator 106 shown in Figure 9 is a modified example of separator 100. It is provided between the first flow channel wall 1A and the second flow channel wall 1B of the third folded portion T3, and one of the first flow channel walls 1A sandwiching the first flow channel groove 2A is not interrupted in part, but the length of the first flow channel wall 1A in the latter half of the first flow channel 10 is shorter than the length of the first flow channel wall 1A in the first half of the first flow channel 10. A first connecting groove J1 is provided in the shortened portion of the first flow channel wall 1A, and the first connecting groove J1 connects to the first flow channel groove 2A.

[0067] Furthermore, one of the third channel walls 1C that sandwiches the second channel groove 2B, which is located between the third channel wall 1C and the fourth channel wall 1D of the fourth folded portion T4, is not interrupted in part, but the length of the third channel wall 1C in the latter half of the first channel 10 is shorter than the length of the third channel wall 1C in the first half of the first channel 10. A second connecting groove J2 is provided in the shortened portion of the third channel wall 1C, and the second connecting groove J2 connects to the second channel groove 2B.

[0068] In the separator 106, the flow path groove 2 connects in the latter half of the first flow path 10, causing a change in the fluid flowability at the return section T. Because the fluid flowability changes between the first and second halves of the first flow path 10, gas is less likely to accumulate in the latter half of the first flow path 10.

[0069] Figure 10 shows a schematic diagram of separator 107. Separator 107 shown in Figure 10 is a modified example of separator 100. The flow path patterns of the third folded portion T3 and the fourth folded portion T4 of separator 107 are different from the flow path patterns of both the first folded portion T1 and the second folded portion T2. ​​The third folded portion T3 is provided with a first connecting groove J1 that connects the first flow path groove 2A and the second flow path groove 2B, and a second connecting groove J2 that connects the second flow path groove 2B and the third flow path groove 2C. Similar first connecting grooves J1 and J2 to those in the third folded portion T3 are provided on the discharge communication passage 5 side of the first flow path 10, which is not a folded portion.

[0070] Furthermore, the corner of the flow channel groove 2 in the fourth folded portion T4 on the side of the second folded portion T2 is inclined. The flow channel pattern of the fourth folded portion T4 in the latter half of the first flow channel 10 can be changed from the flow channel pattern of the first folded portion T1 in the first half of the first flow channel 10 by changing the angle of the corner of the flow channel groove 2, without providing a connecting groove J or blocking the flow channel groove 2. Providing a connecting groove J is preferable because it is more effective in changing the fluid flow ease in the latter half of the first flow channel 10.

[0071] In the separator 107, the flow channel groove 2 is connected in the latter half of the first flow channel 10, and by changing the bending angle of the flow channel groove 2 in the folded-back section T, the ease of fluid flow in the folded-back section T is changed. Because the ease of fluid flow changes between the first and second halves of the first flow channel 10, gas is less likely to accumulate in the latter half of the first flow channel 10.

[0072] Figure 11 shows a schematic diagram of separator 108. Separator 108 shown in Figure 10 is a modified example of separator 101. The first flow channel groove 2A and the second flow channel groove 2B of the fourth folded portion T4 of separator 107 are connected by the first connecting groove J1. The second flow channel groove 2B and the third flow channel groove 2C are connected by the second connecting groove J2. The third flow channel groove 2C and the fourth flow channel groove 2D are connected by the third connecting groove J3.

[0073] Multiple connecting grooves J are also provided in the third folded portion T3 of separator 108. In separator 107, the first flow channel groove 2A and the fourth flow channel groove 2D are connected by the fifth connecting groove J4, the second flow channel groove 2B and the fourth flow channel groove 2D are connected by the sixth connecting groove J5, and the third flow channel groove 2C and the fourth flow channel groove 2D are connected by the third connecting groove J3.

[0074] The extending direction of the connecting groove J in the third folded portion T3 is different from the extending direction of the connecting groove J in the fourth folded portion T4, for example, by 90°.

[0075] In the separator 108, the flow path groove 2 connects in the latter half of the first flow path 10, causing a change in the fluid flow ease at the return section T. Because the fluid flow ease changes between the first and second halves of the first flow path 10, gas is less likely to accumulate in the latter half of the first flow path 10.

[0076] Figure 12 shows a schematic diagram of separator 109. Separator 109 shown in Figure 12 is a modified example of separator 100. Separator 109 has a configuration in which two flow paths, a first flow path 10 and a second flow path 11, are arranged independently in parallel. The first flow path 10 and the second flow path 11 each include a first folded portion T1 and a second folded portion T2. ​​The first folded portion T1 is a folded portion included in the first half of the first flow path 10 and the first half of the second flow path 11, and the second folded portion T2 is a folded portion included in the second half of the flow groove 2. From the outside to the inside of the second folded portion T2, a first flow groove 2A, a second flow groove 2B, a third flow groove 2C, and a fourth flow groove 2D are provided.

[0077] The first channel groove 2A and the second channel groove 2B are connected by the first connecting groove J1, the second channel groove 2B and the third channel groove 2C are connected by the second connecting groove J2, and the third channel groove 2C and the fourth channel groove 2D are connected by the third connecting groove J3. The width of the connecting grooves J tapers from the first connecting groove J1 to the fourth channel groove 2D, meaning that the width of the connecting grooves J narrows in an inclined manner. Since the connecting grooves J connect the channel grooves 2, various shapes of connecting grooves J can be employed in this embodiment.

[0078] Preferably, the first channel 10 and the second channel 11 have the same channel pattern, and each has a different channel pattern in the first half and second half, respectively.

[0079] In the separator 109, the flow path groove 2 is connected in the latter half of the first flow path 10 and the latter half of the second flow path 11, causing a change in the fluid flowability at the folded portion T. Because the fluid flowability changes between the first and second halves of the first flow path 10 and between the first and second halves of the second flow path 11, gas is less likely to accumulate in the latter half of the first flow path 10 and the latter half of the second flow path 11.

[0080] Figure 13 shows a schematic diagram of separator 110. Separator 110 shown in Figure 13 is a modified example of separator 100. Separator 110 has first flow channel grooves 2A and 2B through which fluid flows from the first point P1 to the second point P2, and third flow channel grooves 2C and 4 flow channel grooves 2D through which fluid flows from the second point P2 to the first point P1. The supply side of the second flow channel 11, the second point P2 side, is connected to the supply communication passage 3 and the supply manifold 4. The discharge side of the second flow channel 11, the first point P1 side, is connected to the discharge communication passage 5 and the discharge manifold 6. In other words, the fluid flowing through the first flow channel 10 flows in the opposite direction to the fluid flowing through the second fluid.

[0081] In the first channel 10, the third channel wall 1C between the first channel groove 2A and the second channel groove 2B is interrupted at the fourth folded portion T4, and the first channel groove 2A and the second channel groove 2B are connected at the first connecting groove J1. The channel pattern of the third folded portion T3 and / or the fourth folded portion T4, which are the folded portions T of the latter half of the first channel 10, is different from the channel pattern of the first folded portion T1 and the second folded portion T2, which are the folded portions T of the first half of the first channel 10.

[0082] In the second channel 11, the fourth channel wall 1D between the third channel groove 2C and the fourth channel groove 2D is interrupted at the first folded portion T1, and the third channel groove 2C and the fourth channel groove 2D are connected at the second connecting groove J2. The channel pattern of the first folded portion T1 and / or the second folded portion T2, which are the folded portions T of the latter half of the second channel 11, is different from the channel pattern of the third folded portion T3 and the fourth folded portion T4, which are the folded portions T of the first half of the second channel 11.

[0083] The first channel groove 2A, the second channel groove 2B, the third channel groove 2C, and the fourth channel groove 2D are arranged in parallel, although they divide into two channels in opposite directions of fluid flow.

[0084] In the separator 110, the flow path groove 2 is connected in the latter half of the first flow path 10 and the latter half of the second flow path 11, causing a change in the fluid flowability at the folded portion T. Because the fluid flowability changes between the first and second halves of the first flow path 10 and between the first and second halves of the second flow path 11, gas is less likely to accumulate in the latter half of the first flow path 10 and the latter half of the second flow path 11.

[0085] Figure 14 shows a schematic diagram of separator 111. Separator 111 shown in Figure 14 is a modified example of separator 100. In separator 111, the fourth flow channel groove 2D of the fourth folded portion T4 is blocked by a first blocking wall F1 (blocking wall F). By blocking the flow channel groove 2, the flow channel pattern can be changed, and the ease of fluid flow can be altered by the blocking, making it less likely for gas to accumulate. The first blocking wall F1 is made of, for example, metal and / or resin.

[0086] (Second Embodiment) The second embodiment relates to an electrochemical cell. Schematic diagrams of the electrochemical cell 200 of the second embodiment are shown in Figures 15 and 16. The electrochemical cell 200 is for electrolysis or fuel cell applications.

[0087] The electrochemical cell 200 has an anode 21, a cathode 22, an electrolyte membrane 23, a first separator 24, and a second separator 25.

[0088] The first electrode (anode) 21 has a porous substrate 21A on the first separator 24 side and a catalyst layer 21B on the electrolyte membrane 23 side. The substrate 21A and catalyst layer 21B of the first electrode 21 are made of materials suitable for the anode reaction of the first electrode 21.

[0089] The second electrode (cathode) 22 has a porous substrate 22A on the second separator 25 side and a catalyst layer 22B on the electrolyte membrane 23 side. The substrate 22A and catalyst layer 22B of the second electrode 22 are made of materials suitable for the cathode reaction of the second electrode 22.

[0090] The electrolyte membrane 23 is provided between the first electrode 21 and the second electrode 22. The electrolyte membrane 23 includes, for example, a cation exchange membrane or an anion exchange membrane.

[0091] The first separator 24 is supplied with the fluid used in the reaction of the first electrode 21, and the fluid containing the reactants is discharged from it. The first separator 24 is electrically connected to the first electrode 21.

[0092] The second separator 25 is supplied with the fluid used in the reaction of the second electrode 22, and the fluid containing the reactants is discharged from it. The second separator 25 is electrically connected to the second electrode 22.

[0093] In the first embodiment, the separator 100 is preferably used as the first separator 24 and / or the second separator 25. Either the first separator 24 or the second separator 25 may be a separator that does not have a connecting groove J, a columnar wall K, or a closing wall F.

[0094] The electrochemical cell 200 in Figure 15 uses the separator 100 of the first embodiment for the first separator 24 and the second separator 25.

[0095] The electrochemical cell 200 in Figure 16 uses the separator 100 of the first embodiment as the first separator 24.

[0096] By using the separator 100 of the first or second embodiment, gas is less likely to accumulate inside the separator 100, and the deterioration of the electrolyte membrane 23 can be suppressed.

[0097] (Third embodiment) The third embodiment relates to a stack. Figure 17 is a schematic cross-sectional view showing a stack 300 of the third embodiment. The stack 300 of the third embodiment shown in Figure 17 is formed by connecting multiple electrochemical cells 200 of the second embodiment in series. Clamping plates 31 and 32 are attached to both ends of the stack 300. Modified electrochemical cells can also be used in the third embodiment.

[0098] When performing electrolysis, the amount of carbon compounds such as H2 and CO produced by a single electrochemical cell 200 is small. Similarly, when generating electricity, the amount of electricity produced by a single electrochemical cell 200 is small. Therefore, by configuring a stack 300 with multiple electrochemical cells 200 connected in series, the amount of products and electricity generated increases.

[0099] (Fourth Embodiment) The fourth embodiment relates to an electrolytic device and a fuel cell. An electrochemical cell 200 or a stack 300 using an electrochemical cell 200 is used in the electrolytic device and the fuel cell. Figure 18 shows a schematic diagram of the device 400 of the fourth embodiment. An electrochemical cell 200 is used in the device 400. Figure 19 shows a schematic diagram of the device 401 of the fourth embodiment. An electrochemical cell 200 is used in the device 401. Devices 400 and 401 show some of the configurations of the actual devices. Modified electrochemical cells can also be used in the fifth embodiment.

[0100] The device 400 (401) includes an electrochemical cell 200, an anode current collector plate 41, a cathode current collector plate 42, and a power supply or load 43.

[0101] An anode current collector plate 41 is provided on the first separator 24 of the electrochemical cell 200. The first separator 24 is electrically connected to the anode current collector plate 41.

[0102] A cathode current collector plate 42 is provided on the second separator 25 of the electrochemical cell 200. The second separator 25 is electrically connected to the cathode current collector plate 42.

[0103] A power source or load 43 is connected between the anode current collector plate 41 and the cathode current collector plate 42.

[0104] If the device 400 (401) is an electrolytic device, a power supply 43 is connected between the anode current collector plate 41 and the cathode current collector plate 42.

[0105] If device 400 (401) is a fuel cell, a load 43 is connected between the anode current collector plate 41 and the cathode current collector plate 42. The load 43 may be a power converter, a storage battery, or the like.

[0106] The present invention will be described more specifically below based on examples, but the present invention is not limited to the following examples.

[0107] (Example 1) An electrochemical cell corresponding to Figure 15 was fabricated by using separator 100 from Figure 1 as the first separator 24 and the second separator 25.

[0108] (Example 2) Using separator 101 from Figure 4 as the first separator 24 and second separator 25, an electrochemical cell corresponding to Figure 15 was fabricated. (Example 2) An electrochemical cell corresponding to Figure 15 was fabricated by using separator 103 from Figure 6 as the first separator 24 and the second separator 25.

[0109] (Comparative Example 1) An electrochemical cell corresponding to Figure 15 was fabricated by using separators without the first connecting groove J1 shown in Figure 1 as the first separator 24 and the second separator 25.

[0110] (Comparative Example 2) An electrochemical cell corresponding to Figure 16 was fabricated by using separators, such as the first separator 24 and the second separator 25, which also have the closure wall F in Figure 1 provided in the first folded portion T1.

[0111] Using the electrochemical cells of Examples 1 and 2 and the electrochemical cell of Comparative Example 1, electrolytic operations were performed to generate CO by electrolyzing CO2 under the same conditions. In both Examples 1 and 2, gas accumulated less in the separator than in Comparative Examples 1 to 4, and the rise in cell voltage was suppressed even during long-term operation.

[0112] Using the electrochemical cells of Examples 1 and 2 and the electrochemical cell of Comparative Example 1, fuel cells were operated under the same conditions with methanol as the fuel. In both Examples 1 and 2, gas accumulated less in the separator than in Comparative Example 1, and the decrease in cell voltage was suppressed even during long-term operation.

[0113] The following is a technical proposal for an embodiment. Technical proposal 1 It includes multiple flow channel grooves, a first flow channel connecting a first point and a second point, It has, The first channel has a serpentine channel shape, The midpoint in the longitudinal direction of the first channel is defined as the boundary, and the area from the boundary towards the first point is defined as the first half of the first channel. The section from the boundary towards the second point is defined as the latter half of the first flow path. The first channel includes the folded portion of the first channel in the first half, A separator that includes a folded portion in the latter half of the first flow path having a flow path pattern different from the flow path pattern of the folded portion in the first half of the first flow path. Technical proposal 2 The multiple channel grooves in the first half of the first channel are not connected to each other. The separator described in Technical Proposal 1, wherein some of the multiple channel grooves in the latter half of the first channel are connected to each other. Technical proposal 3 The first channel has a first channel wall, a second channel wall, and a first channel groove sandwiched between the first channel wall and the second channel wall. A separator according to technical proposal 1 or 2, wherein the first channel wall in the latter half of the first channel, or the first channel wall and the second channel wall, are interrupted. Technical proposal 4 A separator according to any one of the technical proposals 1 to 3, wherein the length of the first channel wall in the latter half of the first channel is shorter than the length of the first channel wall in the first half of the first channel. Technical proposal 5 The first channel has a first channel wall, a second channel wall, and a first channel groove sandwiched between the first channel wall and the second channel wall. The first channel has a third channel wall and a second channel groove sandwiched between the first channel wall and the third channel wall. A separator according to any one of Technical Proposals 1 to 4, wherein the first channel groove and the second channel groove are connected in the folded portion of the latter half of the first channel. Technical proposal 6 A separator according to any one of Technical Proposals 1 to 5, wherein the portion of the latter half of the first flow channel in which all flow channel grooves included in the first flow channel are connected is included in the first flow channel. Technical proposal 7 The first channel wall in the latter half of the first channel is interrupted at the folded portion, A separator according to any one of Technical Proposals 1 to 6, comprising a columnar wall between the interrupted portions of the first flow channel wall. Technical proposal 8 The first channel wall in the latter half of the first channel is interrupted at the folded portion, A separator according to any one of Technical Proposals 1 to 7, which includes an island-shaped columnar wall between the interrupted portions of the first flow channel wall. Technical proposal 9 The first channel has a first channel wall, a second channel wall, and a first channel groove sandwiched between the first channel wall and the second channel wall. A separator according to any one of Technical Proposals 1 to 8, wherein the length of the first channel wall in the latter half of the first channel is shorter than the length of the first channel wall in the first half of the first channel. Technical proposal 10 It includes multiple channel grooves, and further includes a second channel connecting the second point and the first point, The second channel has a serpentine channel shape, The midpoint in the longitudinal direction of the second channel is defined as the boundary, and the area from the boundary towards the first point is defined as the first half of the second channel. The section from the boundary towards the second point is defined as the latter half of the second flow path. The first half of the second channel includes the folded portion of the second channel, A separator according to any one of Technical Proposals 1 to 9, wherein the latter half of the second flow path includes a return portion having a flow path pattern different from that of the return portion of the first half of the second flow path. Technical proposal 11 It includes multiple channel grooves, and further includes a second channel connecting the second point and the first point, The second channel has a serpentine channel shape, The midpoint in the longitudinal direction of the second channel is defined as the boundary, and the area from the boundary towards the second point is defined as the first half of the second channel. The section from the boundary towards the first point is defined as the latter half of the second flow path. The first half of the second channel includes the folded portion of the second channel, A separator according to any one of Technical Proposals 1 to 10, wherein the latter half of the second flow path includes a folded portion having a flow path pattern different from that of the folded portion of the first half of the second flow path. Technical proposal 12 The first channel has a first channel wall, a second channel wall, a first channel groove sandwiched between the first channel wall and the second channel wall, a third channel wall, and a second channel groove sandwiched between the second channel wall and the third channel wall. The second channel has a third channel wall, a fourth channel wall, a third channel groove sandwiched between the third channel wall and the fourth channel wall, a fifth channel wall, and a fourth channel groove sandwiched between the fourth channel wall and the fifth channel wall. The first channel groove and the second channel groove are connected, The third channel groove and the fourth channel groove are connected, The separator according to technical proposal 11, wherein the first channel groove, the second channel groove, the third channel groove, and the fourth channel groove are arranged in parallel. Technical proposal 13 First electrode and, The second electrode and, An electrolyte membrane is placed between the first electrode and the second electrode, A first separator in contact with the first electrode, The device comprises a second separator in contact with the second electrode, An electrochemical cell in which the first separator and / or the second separator is a separator as described in any one of Technical Proposals 1 to 12. Technical proposal 14 A stack having an electrochemical cell as described in Technical Proposal 13. Technical proposal 15 An electrolytic device or fuel cell having an electrochemical cell as described in Technical Proposal 13.

[0114] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments described above can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of Symbols]

[0115] 1: Flow channel wall 1A: First channel wall 1B: Second channel wall 1C: Third channel wall 1D: Fourth channel wall 1E: Fifth channel wall 2: Flow channel groove 2A: First channel groove 2B: Second channel groove 2C: Third channel groove 2D: Fourth channel groove 3: Supply communication channels 4: Supply Manifold 5: Discharge connection channel 6: Exhaust manifold 7: Frame 10: First channel 11: Second channel 21: Anode 22: Cathode 23: Electrolyte membrane 24: First separator 25: Second separator 31: Clamping plate 32: Clamping plate 41: Anode current collector plate 42: Cathode current collector plate 43:Power supply 43: Load 100: Separator 101: Separator 102: Separator 103: Separator 104: Separator 105: Separator 106: Separator 107: Separator 108: Separator 109: Separator 110: Separator 111: Separator 200: Electrochemical cell 300: Stack 400: Equipment 401: Equipment F: Obstruction wall F1: 1st blocking wall J: Connection groove J1: First connecting groove J2: Second connecting groove J3: Third connecting groove J4: Fifth connecting groove J5: Sixth connecting groove K: Columnar wall K1: 1st columnar wall K2: 2nd columnar wall K3: 3rd columnar wall P1: Point 1 P2: 2nd point T: Folded part T1: First fold portion T2: Second folded portion T3: Third folded section T4: Fourth fold

Claims

1. A first channel includes multiple channel grooves and connects a first point and a second point, It has, The first channel has a serpentine channel shape, The midpoint in the longitudinal direction of the first flow path is defined as the boundary, and the portion of the first flow path from the boundary towards the first point is defined as the first half of the first flow path. The section from the boundary towards the second point is defined as the latter half of the first flow path. The first half of the first channel includes the folded portion of the first channel, A separator that includes a folded portion in the latter half of the first flow path having a flow path pattern different from the flow path pattern of the folded portion in the first half of the first flow path.

2. The multiple channel grooves in the first half of the first channel are not connected to each other. The separator according to claim 1, wherein some of the multiple flow channel grooves in the latter half of the first flow channel are connected to each other.

3. The first channel has a first channel wall, a second channel wall, and a first channel groove sandwiched between the first channel wall and the second channel wall. The separator according to claim 1, wherein the first channel wall in the latter half of the first channel, or the first channel wall and the second channel wall, are interrupted.

4. The separator according to claim 1, wherein the length of the first channel wall in the latter half of the first channel is shorter than the length of the first channel wall in the first half of the first channel.

5. The first channel has a first channel wall, a second channel wall, and a first channel groove sandwiched between the first channel wall and the second channel wall. The first channel has a third channel wall and a second channel groove sandwiched between the first channel wall and the third channel wall. The separator according to claim 1, wherein the first channel groove and the second channel groove are connected in the folded portion of the latter half of the first channel.

6. The separator according to claim 1, wherein the portion of the latter half of the first flow channel in which all flow channel grooves included in the first flow channel are connected is included in the first flow channel.

7. The first channel wall in the latter half of the first channel is interrupted at the folded portion, The separator according to claim 1, comprising a columnar wall between the interrupted portions of the first flow channel wall.

8. The first channel wall in the latter half of the first channel is interrupted at the folded portion, The separator according to claim 1, which includes island-shaped columnar walls between the interrupted portions of the first flow channel wall.

9. The first channel has a first channel wall, a second channel wall, and a first channel groove sandwiched between the first channel wall and the second channel wall. The separator according to claim 1, wherein the length of the first channel wall in the latter half of the first channel is shorter than the length of the first channel wall in the first half of the first channel.

10. It includes multiple channel grooves, and further includes a second channel connecting the second point and the first point, The second channel has a serpentine channel shape, The midpoint in the longitudinal direction of the second channel is defined as the boundary, and the area from the boundary towards the first point is defined as the first half of the second channel. The section from the boundary towards the second point is defined as the latter half of the second flow path. The first half of the second channel includes the folded portion of the second channel, The separator according to claim 1, wherein the latter half of the second flow path includes a folded portion having a flow path pattern different from the flow path pattern of the folded portion of the first half of the second flow path.

11. It includes multiple channel grooves, and further includes a second channel connecting the second point and the first point, The second channel has a serpentine channel shape, The midpoint in the longitudinal direction of the second channel is defined as the boundary, and the area from the boundary towards the second point is defined as the first half of the second channel. The section from the boundary towards the first point is defined as the latter half of the second flow path. The first half of the second channel includes the folded portion of the second channel, The separator according to claim 1, wherein the latter half of the second flow path includes a folded portion having a flow path pattern different from the flow path pattern of the folded portion of the first half of the second flow path.

12. The first channel has a first channel wall, a second channel wall, a first channel groove sandwiched between the first channel wall and the second channel wall, a third channel wall, and a second channel groove sandwiched between the second channel wall and the third channel wall. The second channel has a third channel wall, a fourth channel wall, a third channel groove sandwiched between the third channel wall and the fourth channel wall, a fifth channel wall, and a fourth channel groove sandwiched between the fourth channel wall and the fifth channel wall. The first channel groove and the second channel groove are connected, The third channel groove and the fourth channel groove are connected, The separator according to claim 11, wherein the first channel groove, the second channel groove, the third channel groove, and the fourth channel groove are arranged in parallel.

13. First electrode and, The second electrode and An electrolyte membrane is placed between the first electrode and the second electrode, A first separator in contact with the first electrode, The device comprises a second separator in contact with the second electrode, An electrochemical cell in which the first separator and / or the second separator is the separator described in any one of claims 1 to 12.

14. A stack having the electrochemical cell according to claim 13.

15. An electrolytic device or fuel cell having the electrochemical cell described in claim 13.

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