Fuel supply control device for electrochemical cell

Abstract

To provide a fuel supply control device for an electrochemical cell capable of uniformly dispersing and supplying fuel to be supplied to the electrochemical cell.SOLUTION: A fuel supply control device 100 comprises a separation plate arranged on one side of an electrochemical cell and including a fuel inlet 112, a fuel outlet 113, and a plurality of fuel channels 111 arranged between the fuel inlet and the fuel outlet, and a fuel supply control plate 120 layered between the separation plate and the electrochemical cell and including a plurality of slits 121 arranged along the length direction of the fuel channel. The channel width of the fuel channel can be varied along the length direction of the fuel channel.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a fuel supply control device for an electrochemical cell, which is capable of supplying fuel to an electrochemical cell in a uniformly dispersed manner. [Background technology]

[0002] Water electrolysis systems using solid oxide cells are devices that separate water into hydrogen and oxygen through electrochemical reactions. Due to their advantages such as high efficiency, high purity of generated hydrogen, and high explosion stability, they are attracting attention as a next-generation means of securing clean hydrogen.

[0003] Furthermore, if the power source used for the electrochemical reaction in a water electrolysis system is replaced with environmentally friendly new renewable energy sources (such as solar energy or wind energy), hydrogen can be produced without polluting the environment, and hydrogen can be produced using surplus electricity, maximizing the utility of new renewable energy sources.

[0004] In general, a water electrolysis system using a solid oxide cell uses a water electrolysis stack assembled by stacking a number of unit cells to meet the required amount of hydrogen production. A unit cell of the water electrolysis stack (hereinafter referred to as an "electrochemical cell") includes an electrolyte membrane capable of transferring oxygen ions, and a fuel electrode and an air electrode sintered on both sides of the electrolyte membrane.

[0005] The electrochemical reaction in an electrochemical cell occurs at the reaction interface between the fuel electrode and the air electrode, and the fuel (i.e., water vapor) supplied to the fuel electrode receives a supply of electrons via an external circuit and power supply device. The water vapor fuel is electrolyzed into oxygen ions and hydrogen to produce hydrogen. The oxygen ions move to the air electrode through the electrolyte membrane and are discharged as oxygen.

[0006] A separator plate may be laminated on each side of the electrochemical cell, and fuel may be supplied to the electrochemical cell through a fuel channel formed in one of the separator plates. However, in a conventional electrochemical cell, the reactivity at the upstream side of the fuel channel is higher than the reactivity at the downstream side of the fuel channel, so that most of the electrochemical reactions are concentrated near the inlet of the fuel channel, which reduces the stability of the electrochemical cell and causes the electrochemical cell to deteriorate. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Korean Patent Publication No. 10-2023-0045469 Summary of the Invention [Problem to be solved by the invention]

[0008] An object of the present invention is to provide a fuel supply control device for an electrochemical cell that can supply fuel to an electrochemical cell in a uniformly dispersed manner. [Means for solving the problem]

[0009] A fuel supply control device for an electrochemical cell according to one embodiment of the present invention includes a separation plate disposed on one side of an electrochemical cell and having a fuel inlet, a fuel outlet, and a plurality of fuel channels arranged between the fuel inlet and the fuel outlet, and a fuel supply control plate stacked between the separation plate and the electrochemical cell and having a plurality of slits arranged along a length of the fuel channels, wherein a channel width of the fuel channels may vary along the length of the fuel channels.

[0010] At least two of the sections divided in each fuel channel have different channel widths, and the channel width may vary stepwise.

[0011] The channel width may increase stepwise from the fuel inlet to the fuel outlet.

[0012] Ribs are disposed between adjacent fuel channels and the ribs may have a rib width that varies in steps along the length of the fuel channel.

[0013] The rib width may decrease stepwise from the fuel inlet to the fuel outlet.

[0014] In each section, the channel width is JPEG2025009692000002.jpg10168, where wci is the channel width in the i-th section, L is the length of the fuel inlet, n is the number of ribs, and wri is the rib width in the i-th section.

[0015] At least two of the sections divided in each fuel channel have different channel widths, and the channel widths may vary gradually.

[0016] The channel width may increase gradually from the fuel inlet to the fuel outlet.

[0017] Ribs may be disposed between adjacent fuel channels and the ribs may have a rib width that varies gradually along the length of the fuel channel.

[0018] The rib width may decrease gradually from the fuel inlet to the fuel outlet.

[0019] The sections in each fuel channel may have the same length.

[0020] The separator plate may further include at least one intersecting channel formed across the plurality of fuel channels to communicate with the plurality of fuel channels.

[0021] The slits located relatively closer to the fuel inlet may have a smaller slit width than the slits located relatively closer to the fuel outlet.

[0022] A spacing between slits located relatively close to the fuel inlet and having the same slit width may be greater than a spacing between slits located relatively close to the fuel outlet and having the same slit width.

[0023] Each slit may extend perpendicular to the fuel channel.

[0024] A fuel supply control device for an electrochemical cell according to another embodiment of the present invention includes a separation plate disposed on one side of an electrochemical cell and having a fuel inlet, a fuel outlet, and a plurality of fuel channels arranged between the fuel inlet and the fuel outlet, and a fuel supply control plate stacked between the separation plate and the electrochemical cell and having a plurality of slits arranged along a length of the fuel channel, wherein the fuel channel and the slits extend in directions intersecting each other, and at least one of a channel width of the fuel channel, a slit width of the slit, and a spacing between the plurality of slits may vary along the length of the fuel channel. Effect of the Invention

[0025] According to an embodiment of the present invention, fuel is supplied to an electrochemical cell in a uniformly dispersed manner, thereby inducing a uniform electrochemical reaction in all reaction regions of the electrochemical cell and minimizing reaction deviations between regions. As a result, the stability of the electrochemical cell and its performance during long-term operation can be improved. [Brief description of the drawings]

[0026] [Figure 1] 1 is an exploded perspective view showing a fuel supply control device for an electrochemical cell according to an embodiment of the present invention; [Diagram 2]1 is an assembled perspective view of a fuel supply control device for an electrochemical cell according to one embodiment of the present invention; [Diagram 3] FIG. 2 is a plan view showing a fuel supply control device for an electrochemical cell according to an embodiment of the present invention. [Figure 4] FIG. [Diagram 5] FIG. 4 is a plan view showing a fuel supply control plate. [Figure 6] FIG. 2 is a diagram showing a fuel flow state in a fuel supply control device for an electrochemical cell according to an embodiment of the present invention. [Figure 7] 1 is a cross-sectional view showing an electrochemical cell equipped with a fuel supply control device according to an embodiment of the present invention. [Figure 8] FIG. 4 is an exploded perspective view showing a fuel supply control device for an electrochemical cell according to another embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] The specific structures or functional descriptions presented in the embodiments of the present invention are merely exemplary for the purpose of describing embodiments according to the concepts of the present invention, which may be embodied in various forms.

[0028] Also, throughout this specification, when a part is said to "comprise" a certain component, this means that it can further include other components, rather than excluding other components, unless specifically stated to the contrary.

[0029] Meanwhile, the terms "first" and / or "second" in the present invention can be used to describe various components, but the components are not limited to the terms. The terms are used only for the purpose of distinguishing one component from another. For example, the first component may be named the second component, and similarly, the second component may be named the first component, without departing from the scope of the concept of the present invention.

[0030] The present invention will now be described in detail with reference to exemplary drawings. When referring to components in each drawing, it should be noted that the same components are designated by the same reference numerals as much as possible even if they are displayed in different drawings.

[0031] FIG. 1 is an exploded perspective view showing a fuel supply control device for an electrochemical cell according to one embodiment of the present invention, FIGS. 2 and 3 are an assembled perspective view and a plan view showing a fuel supply control device for an electrochemical cell according to one embodiment of the present invention, FIG. 4 is a perspective view showing a separation plate, and FIG. 5 is a plan view showing a fuel supply control plate.

[0032] The present invention aims to reduce reaction deviations among regions of the electrochemical cell by uniformly controlling the flow rate of fuel supplied to the electrochemical cell (see 200 in FIG. 8) to induce uniform electrochemical reactions in all active reaction sites of the electrochemical cell, thereby ensuring the stability and performance of the electrochemical cell during long-term operation.

[0033] To this end, the electrochemical cell fuel supply control device 100 according to an embodiment of the present invention is configured to uniformly control the flow rate of fuel supplied to the electrochemical cell 200. The electrochemical cell may be a unit cell of a stack for water electrolysis (i.e., a water electrolysis cell). Such an electrochemical cell can use steam or a mixture of steam and hydrogen as fuel.

[0034] As shown in FIGS. 1 to 3, a fuel supply control device 100 for an electrochemical cell according to one embodiment of the present invention may include a separation plate 110 and a fuel supply control plate 120.

[0035] The separator 110 may be formed of a flat plate having a predetermined thickness and may be stacked and disposed on one side surface of the electrochemical cell 200 .

[0036] 1 and 4, the separator plate 110 may have a plurality of fuel channels 111 on one side surface thereof. In this case, the one side surface of the separator plate is an inner surface facing the electrochemical cell 200. In other words, the fuel channels are formed on the inner surface of the separator plate.

[0037] The fuel channel 111 may be formed in the form of a recessed groove in the inner surface of the separator plate 110. The fuel channel may be formed to have a predetermined length, channel width, and depth.

[0038] The fuel channels 111 may be arranged at a predetermined interval from one another. For example, the fuel channels may be arranged at equal intervals and may all be formed to have the same channel width wc, but this is not necessarily limited thereto. Also, the fuel channels may be arranged in parallel to one another and may all be formed to have the same length.

[0039] Ribs 116 may be disposed between the fuel channels 111. In other words, the fuel channels may be partitioned between the ribs. The rib width wr of the rib may correspond to the spacing between the fuel channels. The ribs may all be formed to have the same rib width, but is not necessarily limited to this.

[0040] When the fuel supply control plate 120 is laminated on the separation plate 110, the plurality of ribs 116 can be in close contact with the surface of the fuel supply control plate that faces the separation plate.

[0041] A plurality of fuel channels 111 may be disposed between a fuel inlet 112 and a fuel outlet 113. That is, the separation plate 110 may include a fuel inlet and a fuel outlet disposed adjacent to both ends of the fuel channels. The fuel inlet and the fuel outlet may be formed in a hole structure having a predetermined length L and width.

[0042] Here, the direction in which the fuel flows from fuel inlet 112 to fuel outlet 113 can be defined as the length direction of separator plate 110, and the direction perpendicular to this length direction can be defined as the width direction of the separator plate.

[0043] Thus, the fuel channels 111 may extend parallel to the length of the separator plate 110. Also, the fuel channels may be arranged at predetermined intervals along the width of the separator plate.

[0044] The fuel inlet 112 and the fuel outlet 113 may extend parallel to the width of the separator plate 110. Thus, the fuel inlet and the fuel outlet may extend in a direction perpendicular to the fuel channel 111. The fuel inlet and the fuel outlet may be disposed adjacent to both ends of the fuel channel in the length direction.

[0045] A first step surface portion 114 may be provided between the fuel inlet 112 and the fuel channel 111. Also, a second step surface portion 115 may be provided between the fuel outlet 113 and the fuel channel 111.

[0046] Each of the stepped surfaces 114 and 115 may be recessed into the inner surface of the separator plate 110 and may be formed to the same depth as the fuel channel 111 .

[0047] The fuel inlet 112 may be formed adjacent to one end of the fuel channel 111 with a first step surface portion 114 as an intermediary. Also, the fuel outlet 113 may be formed adjacent to the other end of the fuel channel 111 with a second step surface portion 115 as an intermediary.

[0048] The fuel inlet 112 and the fuel outlet 113 may be disposed to face each other across the fuel channel 111. In addition, the fuel inlet and the fuel outlet may be formed symmetrically with respect to the fuel channel.

[0049] The fuel inlet 112 and fuel outlet 113 may extend to or through the outermost disposed fuel channel of the fuel channels 111 .

[0050] The fuel supplied to the fuel inlet 112 can flow into the fuel channel 111 through the first step surface portion 114 (see the arrow in FIG. 6). The fuel that has flowed into the fuel channel can be supplied to the electrochemical cell 200 through the fuel supply control plate 120 while passing through the fuel channel. At this time, the fuel that has not been supplied to the electrochemical cell can be discharged to the fuel outlet 113.

[0051] The fuel supply control device 100 for an electrochemical cell according to an embodiment of the present invention is characterized in that the channel width wc of the fuel channel 111 varies along the length of the fuel channel, ie, along the length of the separator plate 110.

[0052] 1 and 4, in each fuel channel 111, the channel width wc1 of the first section 110a located relatively close to the fuel inlet 112 is smaller than the channel width wc2 of the second section 110b located relatively close to the fuel outlet 113. The channel width wc1 of the first section is smaller than the channel width wc3 of the third section 110c located between the first and second sections of the fuel channel. The channel width wc2 of the second section is larger than the channel width wc3 of the third section.

[0053] In this case, in each fuel channel 111, the first section, the second section, and the third section may have the same length h, but is not necessarily limited thereto.

[0054] In this manner, at least two or more of the sections divided in each fuel channel 111 may have different channel widths wc, and the channel widths of the sections may increase stepwise from the fuel inlet 112 toward the fuel outlet 113. In other words, the channel width of each fuel channel may be narrower closer to the fuel inlet and wider closer to the fuel outlet.

[0055] In each rib 116 between adjacent fuel channels 111, the rib width wr corresponding to the first to third sections 110a to 110c can vary along the length of the fuel channel, that is, along the length of the separator plate 110.

[0056] 1 and 4, in each rib 116, the rib width wr1 of the first section 110a located relatively close to the fuel inlet 112 is larger than the rib width wr2 of the second section 110b located relatively close to the fuel outlet 113. The rib width wr1 of the first section is also larger than the rib width wr3 of the third section 110c located between the first and second sections of the rib. The rib width wr2 of the second section is smaller than the rib width wr3 of the third section.

[0057] In each rib 116, the first section, the second section, and the third section may have the same length h, but is not necessarily limited to this.

[0058] In this manner, at least two or more of the sections divided in each rib 116 may have different rib widths wr, and the rib widths of the sections may decrease stepwise from the fuel inlet 112 to the fuel outlet 113. In other words, the rib width of each rib may be wider closer to the fuel inlet and narrower closer to the fuel outlet.

[0059] In this case, the relationship of the channel width wc to the length L and the rib width wr of the fuel inlet 112 in each section can be determined by the following Equation 1.

[0060]

number

[0061] Here, wci is the channel width (mm) in the i-th section, L is the length (mm) of the fuel inlet 112, n is the number of ribs 116, and wri is the rib width (mm) in the i-th section. This relational expression may mean that as the rib width wr decreases, the channel width wc increases. The friction loss coefficient of the fuel channel, i.e., the flow path, can be determined according to the size and shape of the fuel channel 111, which vary from section to section.

[0062] As a result, in the first section 110a, which is located relatively close to the fuel inlet 112 and has the maximum rib width wr and the minimum channel width wc, the flow rate of the fuel in the fuel channel 111 can increase and the pressure drop can increase.

[0063] Conversely, in the second section 110b, which is located relatively close to the fuel outlet 113 and has the smallest rib width wr and the largest channel width wc, the flow velocity of the fuel in the fuel channel 111 decreases and the pressure drop can be reduced.

[0064] Therefore, in order to achieve a uniform fuel supply required at the reaction interface of the electrochemical cell 200, the pressure drop at each slit 121 in the fuel supply control plate 120 can be shared by the fuel channel 111 of the separation plate 110. First, since the pressure drop at the separation plate may increase, for example, the size of each slit in the fuel supply control plate may be increased and the spacing between the slits may be narrowed.

[0065] Optionally, in the fuel supply control device 100 of an electrochemical cell according to one embodiment of the present invention, the separation plate 110 may further include at least one intersecting channel 117 formed across the multiple fuel channels 111 to connect the multiple fuel channels 111 to each other.

[0066] The intersecting channels 117 are formed in a recessed form in the inner surface of the separator plate 110. The intersecting channels are formed to have a predetermined length, width and depth.

[0067] The crossover channels 117 can extend parallel to the width of the separator plate 110 and can pass across and define each fuel channel 111. The crossover channels can separate sections of each rib 116 having different rib widths wr.

[0068] Such cross channels 117 allow multiple fuel channels 111 to communicate together, which advantageously allows the separator plate 110 to more uniformly control the fuel flow rate provided to the electrochemical cell 200 .

[0069] A fuel supply control plate 120 may be laminated and disposed on the inner surface of the separation plate 110 configured in this manner. The fuel supply control plate may be configured to uniformly distribute and deliver the fuel flowing through the fuel channel 111 to the entire reaction region of the electrochemical cell 200.

[0070] The fuel supply control plate 120 may be formed of a flat plate having a predetermined thickness, and may be laminated and disposed on the inner surface of the separation plate 110 .

[0071] As shown in FIGS. 1 to 3 and 5, the fuel supply control plate 120 can have a plurality of slits 121 for controlling the flow rate of fuel supplied to the electrochemical cell 200. As shown in FIG.

[0072] The slits 121 can be formed in the fuel supply control plate 120 by CNC (Computerized Numerical Control) processing, punching processing, laser processing, etching processing, or the like.

[0073] The slit 121 may be formed to penetrate the fuel supply control plate 120 in the thickness direction. The slit may be formed as a linear hole structure having a predetermined length and a slit width ws.

[0074] The slits 121 may be arranged at intervals d from each other along the length of the fuel channel 111, i.e., the length of the separation plate 110. The slits may also be arranged parallel to each other and may all be formed to have the same length.

[0075] Each slit 121 may have a length extending along the arrangement direction of the fuel channels 111, i.e., the width direction of the separation plate 110. This allows each slit to extend in a direction perpendicular to the fuel channels of the separation plate. Also, each slit may extend to a position facing and communicating with the outermost fuel channel among the fuel channels.

[0076] Each slit 121 may have a slit width ws extending along the length direction of the fuel channel 111, i.e., the length direction of the separation plate 110. Among the slits, a slit located relatively closer to the fuel inlet 112 may have a smaller slit width than a slit located relatively farther from the fuel inlet. In other words, the slit width of the slit may increase from the fuel inlet toward the fuel outlet 113.

[0077] 3 and 5, the slit width ws1 of the first slit 121a located relatively close to the fuel inlet 112 is smaller than the slit width ws2 of the second slit 121b located relatively close to the fuel outlet 113. The slit width ws1 of the first slit is smaller than the slit width ws3 of the third slit 121c located between the first and second slits. The slit width ws2 of the second slit is larger than the slit width ws3 of the third slit.

[0078] In this case, the first slits 121a may have the same slit width ws1, the second slits 121b may have the same slit width ws2, and the third slits 121c may have the same slit width ws3.

[0079] In this manner, at least two of the slits 121 may have different slit widths ws, or some of the slits may have the same slit width. Although not shown in the figure, as another modification, all the slits may have different slit widths.

[0080] The first slit 121a may be located corresponding to the first section 110a of each fuel channel 111 of the separator plate 110, the second slit 121b may be located corresponding to the second section 110b of each fuel channel of the separator plate, and the third slit 121c may be located corresponding to the third section 110c of each fuel channel of the separator plate.

[0081] In other words, when the multiple slits 121 of the fuel supply control plate 120 are formed to have, for example, three sizes of slit width ws, each fuel channel 111 of the separation plate 110 can be divided into three sections having different channel widths so as to correspond to slits having the same slit width.

[0082] In addition, the length (h; the length extended in the longitudinal direction of the separation plate) of each section in the separation plate 110 can be determined so as to cover the slits 121 in the fuel supply control plate 120 having the same slit width ws.

[0083] When the fuel supply control plate 120 is laminated to the separation plate 110, the fuel channels 111 and the slits 121 are perpendicular to each other, so that the fuel channels and the slits overlap to form an effective supply area A as shown in FIG.

[0084] The fuel supply control plate 120 having such slits 121 uniformly distributes the fuel that has passed through the fuel channel 111 of the separation plate 110 through the slits and supplies it to the electrochemical cell 200 .

[0085] Also, the spacing d between adjacent slits 121 may decrease from the fuel inlet 112 toward the fuel outlet 113. In other words, the spacing between the slits may be wider closer to the fuel inlet and narrower closer to the fuel outlet.

[0086] 3 and 5, the distance d1 between the first slits 121a located relatively close to the fuel inlet 112 is larger than the distance d2 between the second slits 121b located relatively close to the fuel outlet 113. In addition, the distance d1 between the first slits is larger than the distance d3 between the third slits 121c located between the first and second slits. The distance d2 between the second slits is smaller than the distance d3 between the third slits.

[0087] Among the intervals d between the slits 121, the intervals between slits having the same slit width ws may have the same size, but if at least two or more of the slits have different slit widths, at least two or more intervals may have different sizes. Although not shown in the figure, as another modification, the intervals between the slits may all have different sizes.

[0088] The fuel supply control plate 120 is provided with the slits 121 having the above-mentioned structural characteristics, so that the flow rate of the fuel supplied to the electrochemical cell 200 can be controlled more uniformly.

[0089] In other words, the fuel supply control plate 120 can minimize the reduction in the fuel flow rate delivered to the electrochemical cell 200 downstream of the fuel channel 111 by reducing the spacing d between the slits 121 arranged adjacent to the fuel outlet 113 side, where the fuel flow rate is relatively lower than that of the fuel inlet 112.

[0090] By stacking the fuel supply control plate 120 configured in this manner on the separation plate 110, the fuel supply control device 100 is formed, and the fuel channel 111 and the slit 121 are perpendicular to each other, so that the fuel flowing into the fuel channel can flow and be supplied to the electrochemical cell 200 through the effective supply area A where the fuel channel and the slit overlap.

[0091] For example, for a fuel inlet 112 that requires a smaller effective delivery area A to increase the flow resistance, the effective delivery area can be effectively reduced by increasing the rib width wr of the ribs 116 between the fuel channels 111 without changing the slit width ws of the slits 121.

[0092] In contrast, for the fuel outlet 113 where a small flow resistance must be provided to reduce the pressure drop, the channel width of the fuel channel 111 can be increased to effectively increase the effective supply area A.

[0093] FIG. 6 is a diagram showing the flow state of fuel in a fuel supply control device for an electrochemical cell according to one embodiment of the present invention.

[0094] In FIG. 6, the fuel supply control plate 120 and the separation plate 110 are shown separated with the electrochemical cell omitted in order to indicate the fuel flow rate supplied to the electrochemical cell 200 with an arrow, but in reality the fuel supply control plate is stacked and disposed between the electrochemical cell and the separation plate.

[0095] In addition, in FIG. 6, the solid arrows represent the flow of fuel through the fuel inlet 112, the fuel outlet 113, and the fuel channel 111, and the dotted arrows represent the flow rate of fuel flowing to the electrochemical cell 200 through the fuel supply control plate 120 in the fuel channel 111.

[0096] In addition, in FIG. 6, points 1 (X1) to 7 (X7) are shown on the separation plate 110, and points 8 (X8) to 10 (X10) are shown on the fuel supply control plate 120 to explain the pressure drop of the fuel supplied to the electrochemical cell 200.

[0097] When the fuel supply control plate 120 is stacked between the electrochemical cell 200 and the separation plate 110, first, in the upstream of each fuel channel 111, i.e., the first section 110a, the flow velocity of the fuel supplied to the fuel supply control plate and the pressure drop due to friction loss increase due to the relatively narrow channel width wc1, but due to the narrowed cross-sectional area, the fuel flow rate is relatively reduced compared to the midstream and downstream of the fuel channel, i.e., the third section 110c and the second section 110b.

[0098] Furthermore, in the fuel supply control plate 120, the flow rate of fuel supplied to the electrochemical cell 200 through the first slit 121a having a relatively narrow slit width ws1 is relatively reduced compared to the second slit 121b and the third slit 121c.

[0099] As a result, as the fuel flow rate in the third section 110c and the second section 110b of each fuel channel 111 as well as the third slit 121c and the second slit 121b increases relatively, the fuel flow rate supplied to the reaction active region of the electrochemical cell 200 can be made uniform.

[0100] By controlling the flow rate of the fuel supplied in this manner, the composition of the fuel can be uniformly distributed at the reaction interface of the electrochemical cell, and as a result, the electrochemical reaction can occur uniformly throughout the reaction interface.

[0101] From the viewpoint of fuel pressure drop, in the separator plate 110, the channel width wc of each fuel channel 111 increases toward the fuel outlet 113, so that the fuel flowing in from the fuel inlet 112 passes through the fuel channel quickly upstream and flows relatively slowly downstream. Also, since a larger pressure drop can occur upstream of the fuel channel than downstream, the separator plate shares the pressure drop together with the fuel supply control plate 120.

[0102] In the fuel supply control plate 120, the slit width ws of the slit 121 increases toward the fuel outlet 113, thereby restricting the flow of fuel in the thickness direction upstream of the fuel channel 111 and relatively promoting the flow in the thickness direction downstream. Here, the flow of fuel in the thickness direction refers to the flow in the stacking direction of the separation plate 110 and the fuel supply control plate 120, that is, the flow of fuel moving from the fuel channel 111 of the separation plate to the fuel supply control plate.

[0103] When the pressure difference between point i and point j is ΔPi.j=Pi-Pj, the pressure drop due to friction loss occurring in each fuel channel 111 of the separation plate 110 is ΔP 1.3 >△P 3.5 >△P 5.7 The pressure drop due to friction loss occurring in each slit 121 of the fuel supply control plate 120 can be expressed as follows: ΔP 2.8 >△P 4.9 >△P 6.10 The relationship may be as follows:

[0104] After the fuel flows from the fuel inlet 112 to point i in each fuel channel 111 of the separation plate 110, the final pressure of the fuel when it passes through the slit 121 at point j of the fuel supply control plate 120 corresponding to point i and is supplied to the electrochemical cell 200 can be expressed by Equation 2.

[0105]

number

[0106] Here, △Pcell,j is the final pressure (Pa) of the fuel supplied to the electrochemical cell 200, P 1 is the pressure of fuel supplied at point 1 (Pa), △P channel,k.i is the pressure drop (Pa) that occurs in the fuel channel 111, △P slit,i.j indicates the pressure drop occurring at the slit 121.

[0107] For example, the final pressure of the fuel supplied to the electrochemical cell 200 at point 8 is P 8 =P 1 -(△P 1.2 +△P 2.8 ) The final pressure at point 9 is P 9 =P 3 -(△P 3.4 +△P 4.9 ) and the final pressure at point 10 is P 10 =P 5 -(△P 5.6 +△P 6.10 In this case, the final pressures calculated at points 8 to 10 can be the same.

[0108] Since the pressure drop at each point can be determined by variables corresponding to the shape and size of each section of the fuel channel 111 and the slit 121, in the fuel supply control device 100 for an electrochemical cell according to one embodiment of the present invention, the shape and size of each section of the fuel channel and the slit can be appropriately adjusted to uniform the pressure distribution of the fuel supplied to the electrochemical cell.

[0109] The fuel supply control device 100 for an electrochemical cell according to one embodiment of the present invention can improve the distribution deviation of the fuel (i.e., water vapor) partial pressure within the reaction active area of ​​the electrochemical cell by uniformly controlling the mass flux per unit area of ​​the fuel supplied to the electrochemical cell 200 as a whole, and uniformly form the reversible voltage of the electrochemical cell.

[0110] In addition, in the fuel supply control device 100 for an electrochemical cell according to an embodiment of the present invention, the pressure drop required in the fuel supply control plate 120 can be reduced by the pressure drop occurring in the separation plate 110. The slit width ws of the slit 121 can be made wider, and the slit interval d can be made narrower.

[0111] In this way, the ability to arrange the slits 121 having a wider slit width ws means improved ease of manufacture, which also has the advantage of reducing processing costs.

[0112] FIG. 7 is a cross-sectional view showing an electrochemical cell equipped with a fuel supply control device according to one embodiment of the present invention.

[0113] As shown in FIG. 7, an electrochemical cell 200 equipped with a fuel supply control device 100 according to one embodiment of the present invention may include an anode 201, a cathode 202, and an electrolyte membrane 203 interposed between the anode and the cathode.

[0114] A fuel supply control device 100 according to an embodiment of the present invention may be attached to an anode 201 of an electrochemical cell 200. A fuel supply control plate 120 may be disposed adjacent to the anode 201 and stacked between the separator plate 110 and the anode 201.

[0115] A plate 300 is attached to the air electrode 202, and oxygen decomposed from the electrochemical cell 200 can be discharged through the plate. For this purpose, the plate may have a plurality of channels 301 on one surface.

[0116] Alternatively, the fuel supply control device 100 according to an embodiment of the present invention may be disposed on both sides of the electrochemical cell 200. In this case, in the fuel supply control device disposed on the cathode 202 side, one surface of the separation plate 110 is in close contact with the anode of another electrochemical cell via the fuel supply control plate 120, while the other surface of the separation plate is provided with a channel for the cathode and the other surface is in close contact with the cathode.

[0117] The fuel supply control plate 120 uniformly diffuses the fuel flowing from the fuel channel 111 of the separation plate 110 and supplies it to the electrochemical cell 200. At this time, the fuel is supplied to the anode 201 of the electrochemical cell. As shown by the dotted arrow in Figure 7, the fuel is supplied uniformly to the entire reaction region of the anode, which results in a uniform distribution of the electrochemical reaction at the reaction interface between the anode 201 and the electrolyte membrane 203.

[0118] When fuel is supplied to the fuel electrode 201, the water vapor in the fuel is decomposed into oxygen ions and hydrogen by receiving power, and the oxygen ions move to the air electrode 202 through the electrolyte membrane 203. The oxygen ions that move to the air electrode combine with electrons and can be discharged as oxygen.

[0119] FIG. 8 is an exploded perspective view showing a fuel supply control device for an electrochemical cell according to another embodiment of the present invention.

[0120] As shown in FIG. 8, a fuel supply control device 100 for an electrochemical cell according to another embodiment of the present invention may include a separation plate 110 and a fuel supply control plate 120 .

[0121] In the alternative embodiment shown in Figure 8, only the shape of the fuel channel 111 in the separator plate 110 is different, with the remaining components being the same as those in the embodiment shown in Figures 1 to 7. Whereas the fuel channel in the separator plate of the previous embodiment described above has a rectangular cross-sectional shape, the fuel channel in the separator plate of the alternative embodiment shown in Figure 8 may have a trapezoidal cross-sectional shape.

[0122] A fuel supply control device 100 for an electrochemical cell according to another embodiment of the present invention is characterized in that the channel width wc of the fuel channel 111 varies along the length of the fuel channel, ie, along the length of the separator plate 110.

[0123] Explaining in more detail with reference to FIG. 8, in each fuel channel 111, the channel width wc1 of the first section 110a located relatively close to the fuel inlet 112 is smaller than the channel width wc3 of the second section 110b located relatively close to the fuel outlet 113.

[0124] At the same time, the channel widths wc1 and wc2 of the first section 110a and the second section 110b can be gradually changed.

[0125] For example, one end of the first section 110a in the longitudinal direction, which is located relatively close to the fuel inlet 112, has the smallest channel width of the first section. The channel width wc1 of the first section increases gradually with distance from the fuel inlet. The other end of the first section 110a in the longitudinal direction, which is located relatively far from the fuel inlet, has the largest channel width of the first section.

[0126] Similarly, one end of the second section 110b in the longitudinal direction, which is located relatively close to the fuel outlet 113, has the maximum channel width of the second section. The channel width wc2 of the second section gradually decreases with distance from the fuel outlet. The other end of the second section 110b in the longitudinal direction, which is located relatively far from the fuel outlet, has the minimum channel width of the second section.

[0127] Here, the maximum channel width of the first section 110a is smaller than the minimum channel width of the second section 110b.

[0128] The channel width wc1 of the first section 110a is smaller than the channel width wc3 of the third section 110c located between the first and second sections of the fuel channel 111. In addition, the channel width wc2 of the second section 110b is larger than the channel width wc3 of the third section.

[0129] At the same time, the channel width wc3 of the third section 110c may vary gradually. For example, one end of the third section in the length direction adjacent to the fuel inlet 112 has the smallest channel width of the third section. The channel width of the third section gradually increases as it moves away from the fuel inlet and closer to the fuel outlet 113. The other end of the third section in the length direction adjacent to the fuel outlet has the largest channel width of the third section.

[0130] Here, the maximum channel width of the first section 110a is smaller than the minimum channel width of the third section 110c, while the minimum channel width of the second section 110b is larger than the maximum channel width of the third section 110c.

[0131] In each fuel channel 111, the first section 110a, the second section 110b, and the third section 110c may have the same length as each other, but is not necessarily limited to this.

[0132] In this manner, at least two or more of the sections divided in each fuel channel 111 may have different channel widths wc, and the channel widths of the sections may gradually increase from the fuel inlet 112 to the fuel outlet 113. In other words, the channel widths of the sections in each fuel channel are gradually narrower closer to the fuel inlet and gradually wider closer to the fuel outlet.

[0133] In addition, in each rib 116 between adjacent fuel channels 111, the rib width wr corresponding to the first to third sections 110a to 110c can vary along the length direction of the fuel channel 111, i.e., along the length direction of the separation plate 110.

[0134] Explaining in more detail with reference to FIG. 8, in each rib 116, the rib width wr1 of the first section 110a located relatively close to the fuel inlet 112 is larger than the rib width wr2 of the second section 110b located relatively close to the fuel outlet 113.

[0135] At the same time, the rib widths wr1, wr2 of the first section 110a and the second section 110b can be gradually varied.

[0136] For example, one end of the first section 110a in the longitudinal direction, located relatively close to the fuel inlet 112, has the maximum rib width of the first section. The rib width wr1 of the first section decreases gradually with distance from the fuel inlet. The other end of the first section in the longitudinal direction, located relatively far from the fuel inlet, has the minimum rib width of the first section.

[0137] Similarly, one end of the second section 110b in the longitudinal direction, located relatively close to the fuel outlet 113, has the smallest rib width of the second section. The rib width wr2 of the second section decreases with distance from the fuel outlet. The other end of the second section in the longitudinal direction, located relatively far from the fuel outlet, has the largest rib width of the second section.

[0138] Here, the minimum rib width of the first section 110a is greater than the maximum rib width of the second section 110b.

[0139] The rib width wr1 of the first section 110a is larger than the rib width wr3 of the third section 110c located between the first and second sections of the rib 116. Moreover, the rib width wr2 of the second section 110b is smaller than the rib width of the third section.

[0140] At the same time, the rib width wr3 of the third section 110c can be gradually varied. For example, one end of the third section in the lengthwise direction adjacent to the fuel inlet 112 has the maximum rib width of the third section. The rib width of the third section decreases as it moves away from the fuel inlet and closer to the fuel outlet 113. The other end of the third section in the lengthwise direction adjacent to the fuel outlet has the minimum rib width of the third section.

[0141] Here, the minimum rib width of the first section 110a is greater than the maximum rib width of the third section 110c, while the maximum rib width of the second section 110b is smaller than the minimum rib width of the third section.

[0142] Similarly, in each rib 116, the first section 110a, the second section 110b, and the third section 110c may have the same length as each other, but is not necessarily limited to this.

[0143] In this manner, at least two or more of the divided sections of each rib 116 may have different rib widths wr, and the rib widths of the sections may gradually decrease from the fuel inlet 112 toward the fuel outlet 113. In other words, the rib widths of the sections of each rib become gradually wider closer to the fuel inlet and gradually narrower closer to the fuel outlet.

[0144] As a result, in the first section 110a, which is located relatively close to the fuel inlet 112 and has the maximum rib width wr and the minimum channel width wc, the flow rate of the fuel in the fuel channel 111 can increase and the pressure drop can increase.

[0145] Conversely, in the second section 110b, which is located relatively close to the fuel outlet 113 and has the smallest rib width wr and the largest channel width wc, the flow velocity of the fuel in the fuel channel 111 decreases and the pressure drop can be reduced.

[0146] Therefore, in order to achieve a uniform fuel supply required at the reaction interface of the electrochemical cell 200, the pressure drop at each slit 121 in the fuel supply control plate 120 can be shared by the fuel channel 111 of the separation plate 110. First, since the pressure drop at the separation plate may increase, for example, the size of each slit 121 in the fuel supply control plate may be increased and the distance d between the slits may be narrowed.

[0147] Optionally, in the fuel supply control device 100 of an electrochemical cell according to one embodiment of the present invention, the separation plate 110 may further include at least one intersecting channel 117 formed across the multiple fuel channels 111 to connect the multiple fuel channels 111 to each other.

[0148] The cross channels 117 may extend parallel to the width of the separator plate 110 and may pass across each of the fuel channels 111. In this way, the cross channels may separate sections of each rib 116 having different rib widths wr.

[0149] Such cross channels 117 allow multiple fuel channels 111 to communicate together, which advantageously allows the separator plate 110 to more uniformly control the rate of fuel flow provided to the electrochemical cell 200 .

[0150] A fuel supply control plate 120 may be laminated and disposed on the inner surface of the separation plate 110 configured in this manner. The fuel supply control plate may be configured to uniformly distribute and deliver the fuel flowing through the fuel channel 111 to the entire reaction region of the electrochemical cell 200.

[0151] As described above, according to the embodiment of the present invention, the fuel supplied to the electrochemical cell is uniformly dispersed and supplied, thereby inducing a uniform electrochemical reaction in all reaction regions of the electrochemical cell and minimizing reaction deviations among regions. As a result, the stability of the electrochemical cell and performance during long-term operation can be improved.

[0152] The above description is merely an illustrative example of the technical concept of the present invention, and various modifications and variations can be made by a person having ordinary knowledge in the technical field to which the present invention pertains without departing from the essential characteristics of the present invention.

[0153] Therefore, the embodiments disclosed in the present invention are for illustration purposes only and are not intended to limit the technical idea of ​​the present invention, and the scope of the technical idea of ​​the present invention is not limited by such embodiments. The scope of protection of the present invention should be interpreted according to the following claims, and all technical ideas within the scope equivalent thereto should be interpreted as being included in the scope of the present invention. [Explanation of symbols]

[0154] 100: Fuel supply control device 110: Separation plate 110a: First Section 110b: Second Section 110c: Third Section 111: Fuel channel 112:Fuel inlet 113:Fuel outlet 114: 1st step surface part 115: 2nd step surface part 116: Rib 117: Cross Channel 120: Fuel supply control board 121: Slit 121a: First slit 121b: Second slit 121c: 3rd slit 200: Electrochemical cell 201:Fuel electrode 202: Air electrode 203: Electrolyte membrane 300: Plate 301:Channel

Claims

1. a separator plate disposed on one side of the electrochemical cell, the separator plate including a fuel inlet, a fuel outlet, and a plurality of fuel channels arranged between the fuel inlet and the fuel outlet; a fuel supply control plate laminated between the separator plate and the electrochemical cell, the fuel supply control plate having a plurality of slits arranged along the length of the fuel channel; Including, A fuel delivery control device for an electrochemical cell, wherein a channel width of the fuel channel varies along a length of the fuel channel.

2. 2. The fuel supply control device for an electrochemical cell according to claim 1, wherein at least two or more of the plurality of sections divided in each fuel channel have different channel widths, and the channel width changes stepwise.

3. The fuel supply control device of claim 2 , wherein the channel width increases stepwise from the fuel inlet to the fuel outlet.

4. A rib is disposed between adjacent fuel channels; 3. The electrochemical cell fuel supply control device of claim 2, wherein the rib width of the rib varies in stages along the length of the fuel channel.

5. The fuel supply control device of claim 4 , wherein the rib width decreases in a stepwise manner from the fuel inlet to the fuel outlet.

6. In each interval, the channel width is determined by Equation 1: [0010] 5. The fuel supply control device for an electrochemical cell as claimed in claim 4, wherein wci is the channel width in the i-th section, L is the length of the fuel inlet, n is the number of ribs, and wri is the rib width in the i-th section.

7. 2 . The fuel supply control device for an electrochemical cell according to claim 1 , wherein at least two or more of the sections divided in each fuel channel have different channel widths, and the channel widths change gradually.

8. The device of claim 7 , wherein the channel width increases gradually from the fuel inlet to the fuel outlet.

9. A rib is disposed between adjacent fuel channels; 8. The electrochemical cell fuel supply control of claim 7, wherein the rib width of the rib varies gradually along the length of the fuel channel.

10. 10. The fuel supply control device of claim 9, wherein the rib width decreases progressively from the fuel inlet to the fuel outlet.

11. The fuel supply control device for an electrochemical cell according to claim 2 or 7, wherein in each fuel channel, the plurality of sections have the same length as each other.

12. 2. The fuel supply control device for an electrochemical cell according to claim 1, wherein said separator plate further includes at least one intersecting channel formed across said plurality of fuel channels to communicate said plurality of fuel channels.

13. 2. The fuel supply control device for an electrochemical cell according to claim 1, wherein the slit located relatively close to the fuel inlet has a smaller slit width than the slit located relatively close to the fuel outlet.

14. 14. The fuel supply control device for an electrochemical cell as described in claim 13, wherein a distance between slits located relatively close to the fuel inlet and having the same slit width is greater than a distance between slits located relatively close to the fuel outlet and having the same slit width.

15. The fuel supply control device for an electrochemical cell according to claim 1 , wherein each slit extends in a direction perpendicular to the fuel channel.

16. a separator plate disposed on one side of the electrochemical cell, the separator plate having a fuel inlet, a fuel outlet, and a plurality of fuel channels arranged between the fuel inlet and the fuel outlet; a fuel supply control plate laminated between the separator plate and the electrochemical cell, the fuel supply control plate having a plurality of slits arranged along the length of the fuel channel; Including, The fuel channel and the slit extend in a direction intersecting each other, 11. A fuel supply control device for an electrochemical cell, wherein at least one of a channel width of the fuel channel, a slit width of the slit, and a spacing between the slits varies along a length of the fuel channel.

17. The device of claim 16 , wherein the channel width increases in a stepwise manner from the fuel inlet to the fuel outlet.

18. 17. The apparatus of claim 16, wherein the channel width increases progressively from the fuel inlet to the fuel outlet.

19. 17. The fuel supply control device of claim 16, wherein the slit located relatively closer to the fuel inlet has a smaller slit width than the slit located relatively closer to the fuel outlet.

20. 17. The fuel supply control device of claim 16, wherein the spacing between the plurality of slits decreases from the fuel inlet to the fuel outlet.

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