Separator plate for electrochemical cell and fuel cell
By designing a specific connection method between corrugated channels and inclined channels on the fuel cell partition, the problems of uneven gas distribution and interlocking channels in the fuel cell are solved, and the operating efficiency and assembly reliability of the fuel cell are improved.
Patent Information
- Application Number
- CN202380068588.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2022-09-26
- Filing Date
- 2023-09-25
- Publication Date
- 2025-07-08
AI Technical Summary
In fuel cells, the channel design of the reaction gas leads to uneven gas distribution and head loss, and the corrugated channels of different partitions are easily interlocked when stacked and assembled.
A partition plate is designed, where the ends of the corrugated channel extend in the same direction and form corrugated channels of the same period. The joint points connected to the inclined channel and the corrugated channel are regularly spaced in parallel straight lines. The connection between the inclined channel and the corrugated channel is consistent to ensure uniform gas distribution and prevent interlocking.
A uniform distribution of the reaction gas in the fuel cell is achieved, reducing head loss, and preventing the partition channel interlocking during assembly.
Smart Images
Figure CN120283316A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a fuel cell. Background Art
[0002] Such a fuel cell includes stacked electrochemical cells, each electrochemical cell generally including: an electrolyte membrane having a first major surface and a second major surface opposite to each other; a first catalytic layer and a second catalytic layer arranged against the first major surface and the second major surface of the electrolyte membrane; and two separator plates, with the first catalytic layer and the second catalytic layer respectively arranged between one of the separator plates and the electrolyte membrane.
[0003] Channels for circulating reaction gases are provided on the separator plates. Specifically, each separator plate may include corrugated channels extending along the same first direction and connected to inclined channels that are straight.
[0004] The inclined channels can be connected to portions of the corrugated channels that have different orientations relative to the first direction.
[0005] In this case, the head losses of the reaction gases circulating in the channels are not the same, which depends on the orientation at the junction points.
[0006] Therefore, the flow rates of the reaction gases in all the channels are not the same, and the operation of the fuel cell is not optimal.
[0007] In fact, the gas distribution in contact with the catalytic layer adjacent to the separator plate is uneven.
[0008] It can also be arranged that the ends of the corrugated channels connected to the inclined channels are straight and parallel to each other.
[0009] However, in this case, when the separator plates are pressed against each other, the ends of the corrugated channels of different separator plates have the risk of interlocking with each other during stack assembly. Summary of the Invention
[0010] In such a background, the present invention aims to propose a separator plate for an electrochemical cell of a fuel cell to help solve the above problems.
[0011] To this end, the present invention relates to a separator for an electrochemical cell of a fuel cell, the separator comprising on a first face: a plurality of corrugated channels for circulating a first reaction gas, the plurality of corrugated channels having respective ends, the ends all extending along the same first direction and forming corrugations having the same specific period; and a plurality of inclined channels, each of the plurality of inclined channels extending along a second direction intersecting the first direction, each end of each of the plurality of corrugated channels being connected at a junction point to one of the plurality of inclined channels; the junction point defining a projection point, the projection point being projected onto a straight line parallel to the first direction, the projection being carried out in a third direction perpendicular to the first direction, the projection points being regularly spaced apart from each other along the first direction and being separated from each other by a constant gap equal to a multiple of the specific period.
[0012] Since the projection points are regularly spaced apart from each other along the first direction and are separated from each other by a constant gap equal to a multiple of the specific period, for all the corrugated channels, the ends of the corrugated channels at the junction points always have the same orientation.
[0013] Therefore, for all the corrugated channels, the connection between the inclined channels and the corrugated channels is substantially the same.
[0014] The head loss of the reaction gas circulating in the channels is actually the same, so that the distribution of the reaction gas in different corrugated channels is uniform.
[0015] Therefore, the first catalytic layer is uniformly supplied with the reaction gas, and the operation of the fuel cell is improved.
[0016] In addition, the ends of the corrugated channels have corrugations, which helps to prevent the channels of different separators from interlocking with each other when assembling the fuel cell.
[0017] The separator may also have one or more of the following features, which may be considered individually or in all technically feasible combinations:
[0018] The projection points are separated from each other by a constant gap equal to the specific period;
[0019] Each of the corrugated channels includes a main body portion extending along the first direction and forming large corrugations having a specific long period greater than the specific period of the corrugations at the ends, the ends of the corrugated channels extending between the main body portion and the junction points of the corrugated channels;
[0020] The number of the inclined channels is less than the number of the corrugated channels, and a plurality of corrugated channels lead to the same inclined channel;
[0021] The junction points of the plurality of corrugated channels leading to the same inclined channel define the same projection point on the straight line;
[0022] The junction points of the plurality of corrugated channels leading to the same inclined channel define at least two different projection points on the straight line;
[0023] The junction points are located on a straight line intersecting the first direction;
[0024] The ends of the plurality of corrugated channels have respective tangents at their junction points, and the tangents are all parallel to each other;
[0025] The inclined channel has inclined ends connected to the junction points, and the inclined ends are straight lines and parallel to each other;
[0026] The inclined ends extend along a third direction perpendicular to the first direction.
[0027] According to a second aspect, the present invention relates to a fuel cell including a plurality of electrochemical cells, each electrochemical cell including: an electrolyte membrane having a first major surface and a second major surface opposite to each other; a first catalytic layer and a second catalytic layer, the first catalytic layer and the second catalytic layer being arranged against the first major surface and the second major surface of the electrolyte membrane; a separator plate having the above characteristics, and the first catalytic layer being arranged between the first surface of the separator plate and the electrolyte membrane. BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Other features and advantages of the present invention will become clear from the following description given by way of example with reference to the accompanying drawings, but are in no way limited thereto, wherein:
[0029] Figure 1 is a simplified exploded schematic view of a cell unit of a fuel cell according to the present invention;
[0030] Figure 2 is Figure 1 a partial schematic perspective view of the cell unit of the fuel cell shown;
[0031] Figure 3 is Figure 1 and Figure 2 a top view schematic of the channels of the first separator plate shown;
[0032] Figure 4 is Figure 1 an enlarged top view of region IV of the first separator plate shown for a variant embodiment; and
[0033] Figure 5 is Figure 3 a schematic diagram similar to that shown for another variant embodiment. Specific embodiments
[0034] As Figure 1 And Figure 2 shown, the fuel cell 1 includes stacked electrochemical cells, each electrochemical cell including an electrolyte membrane 3 having a first major face 5 and a second major face 7.
[0035] The electrochemical cells of the fuel cell further include a first catalytic layer 9 and a second catalytic layer 11, the first catalytic layer 9 and the second catalytic layer 11 being arranged against the first major face 5 and the second major face 7 of the electrolyte membrane 3, for example by being formed on the first major face 5 and the second major face 7 of the electrolyte membrane 3, or at least one catalytic layer or both catalytic layers being formed on a gas diffusion layer which is arranged against the corresponding major face 5 or 7 of the electrolyte membrane 3.
[0036] For example, the membrane is a proton exchange polymer membrane.
[0037] Typically, the gas diffusion layer 13 is arranged against the first catalytic layer 9, opposite the electrolyte membrane 3. Similarly, another gas diffusion layer 15 is arranged against the second catalytic layer 11, opposite the membrane 3.
[0038] For example, the first catalytic layer 9 (optionally together with layer 13) forms the anode. The second catalytic layer 11 (optionally together with layer 15) forms the cathode.
[0039] The electrolyte membrane 3, the first catalytic layer 9 and the second catalytic layer 11, and the gas diffusion layers 13 and 15 together belong to the membrane electrode assembly (MEA) 17.
[0040] The membrane electrode assembly 17 of the fuel cell 1 typically further includes a frame 19 which internally defines a window within which the electrolyte membrane 3 is fixed. For example, the frame 19 is mainly formed by one or two polymer membranes, such as polyethylene naphthalate or polyethylene terephthalate (PEN or PET), the total thickness of which can be less than 200 micrometers or even less than 100 micrometers.
[0041] Each electrochemical cell of the fuel cell 1 further includes a first separator 21 having a first face 22a and a second face 22b opposite the first face 22a. The first catalytic layer 9 is arranged between the first face 22a of the first separator 21 and the electrolyte membrane 3.
[0042] In the example shown, the gas diffusion layer 13 and the first catalytic layer 9 are between the first face 22a of the first separator 21 and the electrolyte membrane 3.
[0043] Symmetrically, each electrochemical cell of the fuel cell 1 includes a second separator 23 having a first face 24a and a second face 24b opposite to the first face 24a. The second catalyst layer 11 is disposed between the first face 24a and the electrolyte membrane 3.
[0044] More precisely, the gas diffusion layer 15 and the second catalyst layer 11 are interposed between the first face 24a of the second separator 23 and the electrolyte membrane 3.
[0045] The first separator 21 carries a channel group 25 for circulating the first reaction gas.
[0046] The channel group 25 is formed on the first face 22a of the first separator 21, and the first face 22a is oriented towards the first catalyst layer 9 of the electrochemical cell under consideration, and thus also towards the electrolyte membrane 3 of the electrochemical cell under consideration.
[0047] The first reaction gas is typically hydrogen.
[0048] A channel group 27 is formed on the first face 24a of the second separator 23, and the first face 24a is oriented towards the second catalyst layer 11 of the electrochemical cell under consideration, and thus also towards the electrolyte membrane 3 of the electrochemical cell under consideration. The channels 27 are provided for circulating the second reaction gas.
[0049] The second reaction gas is typically air, or oxygen, or any other suitable gas.
[0050] The separator 21, the membrane electrode assembly 17 and the second separator 23 are stacked along the stacking direction E, one above the other.
[0051] The stacking direction E is shown in Figure 1 .
[0052] Together they define a cell unit of the fuel cell 1. Seals (not shown) are typically provided between each separator and the MEA. The fuel cell 1 includes a large number of cell units that are stacked on top of each other along the stacking direction E.
[0053] Only one cell unit is shown in Figure 1 and Figure 2 .
[0054] Thus, the first separator 21 of one cell unit overlaps and is in electrical contact with the second separator 23 of an adjacent cell unit in the stack.
[0055] In certain fuel cell configurations, channels 29 for circulating a heat transfer fluid are formed between a first separator plate 21 of a cell unit and a second separator plate 23 of an adjacent cell unit, and thus are formed between two adjacent cell units. The second faces 22b / 24b of the two plates may be welded together or joined to each other, or simply clamped against each other in a cell unit stack, and in particular in the latter case, a sealing system may be provided between the two plates. The heat transfer fluid is used to cool the cell units of the fuel cell during operation of the fuel cell.
[0056] In Figure 1 it, the circulation channels 29 for the heat transfer fluid are not shown on the second separator plate 23.
[0057] In the example shown, the first separator plate 21, the second separator plate 23, and the frame 19 are rectangular and each has substantially the same shape and dimensions as each other.
[0058] As Figure 1 shown, the first separator plate 21, the second separator plate 23, and the frame 19 have a generally elongated shape along the longitudinal direction L.
[0059] Holes 31a, 31b, and 31c are provided in the first separator plate 21, the frame 19, and the second separator plate 23, respectively. The holes 31a, 31b, and 31c are placed in alignment with each other and form a distribution manifold for a first reactant gas.
[0060] The holes 31a, 31b, and 31c are preferably placed at the corners of the first separator plate 21, the frame 19, and the second separator plate 23, respectively.
[0061] The first separator plate 21, the frame 19, and the second separator plate 23 further include holes 32a, 32b, and 32c that are placed in alignment with each other. The holes 32a, 32b, and 32c define a collector for discharging the first reactant gas. The holes 32a, 32b, and 32c are preferably placed at the corners opposite to the holes 31a, 31b, and 31c.
[0062] The first separator plate 21, the frame 19, and the second separator plate 23 further include holes 33a, 33b, and 33c that are placed in alignment with each other, respectively. These holes define a manifold for distributing a second reactant gas. The holes 33a, 33b, and 33c are preferably located at another corner of the first separator plate 21, the frame 19, and the second separator plate 23, respectively.
[0063] The first separator plate 21, the frame 19, and the second separator plate 23 also have holes 34a, 34b, and 34c that are placed in alignment with each other, respectively. The holes 34a, 34b, and 34c are preferably placed at the corners opposite to the holes 33a, 33b, and 33c. These holes define an exhaust manifold for the second reactant gas.
[0064] The first separator 21, the frame 19, and the second separator 23 also have holes 35a, 35b, and 35c that are placed to coincide with each other. The holes 35a, 35b, and 35c together define a heat transfer fluid supply manifold. For example, the holes 35a, 35b, and 35c are respectively located between the holes 34a and 31a, between the holes 34b and 31b, and between the holes 34c and 31c.
[0065] Finally, the first separator 21, the frame 19, and the second separator 23 respectively define holes 36a, 36b, and 36c that are placed to coincide with each other. The holes 36a, 36b, and 36c together define a heat transfer fluid discharge manifold. For example, the holes 36a, 36b, and 36c are respectively placed between the holes 32a and 33a, between the holes 32b and 33b, and between the holes 32c and 33c.
[0066] For example, the holes 34a, 35a, and 31a are placed at the longitudinal ends of the first separator 21 and are arranged side by side transversely in the width direction of the plate. For another example, the holes 32a, 36a, and 33a are placed at the other longitudinal end of the first separator 21 and are arranged side by side transversely in the width direction of the plate.
[0067] The holes 34b, 35b, and 31b are placed at the longitudinal ends of the frame 19 and are arranged side by side transversely in the width direction of the frame. The holes 32b, 36b, and 33b are placed at the other longitudinal end of the frame 19 and are arranged side by side transversely in the width direction of the frame.
[0068] The holes 34c, 35c, and 31c are placed at the longitudinal ends of the second separator 23 and are arranged side by side transversely in the width direction of the plate. The holes 32c, 36c, and 33c are placed at the other longitudinal end of the second separator 23 and are arranged side by side transversely in the width direction of the plate.
[0069] The channel group 25 formed on the first separator 21 ensures that the first reaction gas circulates from the hole 31a to the hole 32a on the first surface 22a of the first separator facing the electrolyte membrane 3.
[0070] Similarly, the channel group 27 formed on the second separator 23 ensures that the second reaction gas circulates from the hole 33c to the hole 34c on the first surface 24a of the second separator facing the electrolyte membrane 3.
[0071] The above-mentioned circulation direction in the channel group 25 and / or the channel group 27 is an example, and for one or the other of the groups, or for both, this direction can be opposite.
[0072] As Figure 1 shown, the first separator 21 has a central region 38, and the channels of the channel group 25 extend in a general direction parallel to the longitudinal direction L in the central region 38.
[0073] The first separator 21 further includes a distribution region 40 which is longitudinally between the central region 38 and the end of the first distribution plate 21 where holes 31a, 35a and 34a are formed along the longitudinal direction L.
[0074] Among the channels of the channel group 25, the channels formed in the distribution region 40 include inclined channels 56 which extend along a general direction inclined with respect to the longitudinal direction L and fluidly connect the channels of the central region 38 to the holes 31a. At least one section of the inclined channels 56 can be perpendicular to the longitudinal direction L, as will be seen with reference to Figure 4 what follows.
[0075] The first separator 21 further includes a second distribution region 42. The second distribution region 42 is longitudinally between the central region 38 and the other longitudinal end of the first separator 21, where holes 32a, 36a and 33a are formed.
[0076] Among the channels of the channel group 25, the channels formed in the second distribution region 42 include inclined channels 56 which extend along a general direction inclined with respect to the longitudinal direction L and fluidly connect the channels of the central region 38 to the holes 32a. At least one section of these inclined channels 56 can be perpendicular to the longitudinal direction L.
[0077] The second separator 23 is the same as the first separator.
[0078] The second separator 23 also has a central region 44 where the channels of the assembly 27 extend along a general direction parallel to the longitudinal direction L. The second separator 23 includes a distribution region 46 where the channels of the assembly 27 extend along a general direction inclined with respect to the longitudinal direction L. These channels enable the channels of the central region 44 to be fluidly connected to the holes 33c. The second separator 23 further includes a second distribution region 48 where the channels of the assembly 27 extend along a general direction inclined with respect to the longitudinal direction L. The channels are for fluidly connecting the channels of the central region 44 to the holes 34c.
[0079] The distribution region 46 is longitudinally between the central region 44 and the end of the second separator 23 where holes 32c, 36c and 33c are formed. Another distribution region 48 is longitudinally between the central region 44 and the end of the second separator 23 where holes 31c, 35c and 34c are formed.
[0080] Regions 44, 46 and 48 are demarcated by dashed lines in Figure 1 because the channels 27 for circulating the second reaction gas are formed on the first face 24a of the separator 23 and are not visible in Figure 1 what follows.
[0081] According to the present invention, and as Figure 3 shown, the first partition plate 21 includes a plurality of corrugated channels 49 for circulating a first reaction gas. The corrugated channels 49 have ends 50, and all the ends 50 extend along the same first direction D1 and form corrugations having the same first specific period T1.
[0082] The corrugated channels 49 form part of a channel group 25 to ensure the circulation of the first reaction gas.
[0083] Each end 50 extends along the first direction D1, which means that the end 50 extends along a general direction parallel to the first direction D1.
[0084] The corrugations of the ends 50 alternately form protrusions 52 on both sides of a center line C parallel to the first direction D1. All the protrusions 52 perpendicular to the center line C have the same lateral offset from the center line C in the Figure 3 plane, Figure 3 and the plane is an extended plane of the first partition plate.
[0085] The lateral offset corresponds to the distance between the center line C and the top of the protrusion 52 perpendicular to the first direction D1.
[0086] The period T1 corresponds to the spacing between the tops 54 of two consecutive protrusions located on the same side of the center line C, and this spacing is measured along the center line C in the first direction D1.
[0087] The corrugations of the ends 50 are in phase in the first direction D1.
[0088] This means that the protrusions 52 of different ends 50 are located at the same positions along the first direction D1. In other words, for a given end 50, all the protrusions 52 located on the first side of the center line C are located at the same positions along the first direction D1 as the protrusions of other ends 50 located on the same side.
[0089] In the example shown, the protrusions 52 of all the ends 50 have the same lateral offset.
[0090] The spacing between the respective center lines C of the ends 50 of different corrugated channels is substantially constant. This spacing is measured perpendicular to the first direction D1.
[0091] In Figure 3 and Figure 5 , for the sake of clarity of the drawings, the spacing between the corrugated channels 49 is greatly exaggerated compared to the width of the corrugated channels 49.
[0092] The first partition plate 21 further includes a plurality of inclined channels 56, and each inclined channel 56 extends along a second direction D2 intersecting the first direction D1.
[0093] The inclined channels 56 are part of the channel group 25 that ensures the circulation of the first reaction gas.
[0094] In the example shown, the inclined channels 56 are parallel to each other and thus all extend along the same second direction D2 that intersects the first direction D1.
[0095] In a variant, the inclined channels 56 extend along respective second directions that are slightly different from each other and form an angle of at most 30°, preferably at most 15°, with each other.
[0096] The spacing between the inclined channels 56 is substantially constant. This spacing is measured perpendicular to the second direction D2.
[0097] The corrugated channels 49 are typically formed on the central region 38. At this time, the first direction D1 corresponds to the longitudinal direction L. The inclined channels 56 are typically formed in the distribution regions 40 or 42.
[0098] As Figure 3 shown, the end 50 of each corrugated channel 49 is connected to one of the inclined channels 56 at the junction point 58.
[0099] The end 50 is directly connected to the corresponding inclined channel 56. This means that the inclined channel 56 directly continues the end 50, and the first reaction gas flows between the inclined channel 56 and the end 50 of the corrugated channel.
[0100] The inclined channel 56 has an inclined end 60 connected to the junction point 58.
[0101] The inclined ends 60 are preferably straight and parallel to each other. These inclined ends 60 extend along the second direction D2.
[0102] The angle formed by the second direction D2 and the first direction D1 generally includes an angle between 30° and 90°. For example, the second direction D2 is perpendicular to the first direction D1.
[0103] The junction point 58 defines a projection point p ( Figure 3 ) projected onto a straight line D parallel to the first direction D1. This projection is carried out in a third direction D3 perpendicular to the first direction D1.
[0104] The projection points p are regularly spaced from each other along the first direction D1 and are separated from each other by a constant gap equal to a multiple of a specific period T1.
[0105] Here, the gap equal to a multiple of the specific period T1 means that the gap is equal to the specific period T1 multiplied by an integer greater than or equal to 1.
[0106] In other words, the joining points 58 are regularly spaced from each other along the first direction D1. The joining points 58 are separated from each other by a constant gap equal to a multiple of a specific period T1.
[0107] In the example shown, the gap between the projection points p is equal to the period T1.
[0108] In a variant, the gap is twice T1, or three times T1, or any other multiple.
[0109] Thus, as Figure 3 shown, the ends 50 of the corrugated channels have respective tangents T at their joining points 58, and all the tangents are parallel to each other.
[0110] What is considered here is the tangent of the end 50 of the corrugated channel at the joining point 58.
[0111] Therefore, regardless of which corrugated channel 25 is considered, the inclination between the end of the inclined channel 56 at the joining point 58 and the end of the end 50 at the joining point 58 is substantially the same.
[0112] If the inclined ends 60 of all the inclined channels 56 are oriented along the same second direction, the inclination is exactly the same.
[0113] If the inclined ends 60 do not all extend along the same second direction, the inclination between different channels may be slightly different from each other.
[0114] However, since the inclined ends 60 extend in directions close to each other, the inclinations at different joining points 58 are close to each other, such that the head losses of the first reaction gas flowing in different channels are not significantly different.
[0115] Figure 4 An example of the first separator 21 is shown in more detail. Figure 4 Only one area of the separator is shown in Figure 4 The view in Figure 1 is an enlarged view of the area IV shown in
[0116] In Figure 4 it can be seen that each corrugated channel 49 includes a main body portion 62 that extends along the first direction D1 and forms large corrugations.
[0117] Generally, the main body portion 62 extends over a larger part of the length of the central region 38. Here, the first direction D1 corresponds to the longitudinal direction L.
[0118] The ends 50 continue the main body portion 62 of a given corrugated channel 49.
[0119] The large corrugations have a defined long period T2 which is greater than the specific period T1 of the corrugations at the end portion 50.
[0120] The main body portion 62 extends along the same centerline C as the end portion 50. The large corrugations form protrusions 64 on either side of the centerline C. The long period T2 corresponds to the spacing measured in the first direction D1 between the tops of two consecutive protrusions 64 located on the same side of the centerline C.
[0121] Generally, the long period T2 is included between 1.5 times and 20 times the period T1, or preferably between 5 times and 15 times the period T1.
[0122] The lateral offset of the protrusion 64 in the direction perpendicular to the centerline C is greater than the lateral offset of the protrusion 52.
[0123] The large corrugations of the main body portions 62 of different channels are in phase, i.e., the protrusions 64 of different channels are at the same height along the first direction D1.
[0124] The end portion 50 and the main body portion 62 of the same corrugation channel 49 meet at the end point 65.
[0125] The end point 65 corresponds to the limit between the small corrugations and the large corrugations. The end points 65 of different corrugation channels are aligned along a third direction D3 perpendicular to the first direction D1.
[0126] In Figure 3 the example of the illustrated embodiment, the number of inclined channels 56 is equal to the number of corrugation channels 49. Each corrugation channel 49 leads to a different inclined channel 56.
[0127] In Figure 3 the example shown, the junction points 58 are placed on a straight line. The straight line C’ is shown in Figure 3 by a dotted line. The straight line C’ intersects the first direction D1.
[0128] The straight line C’ also intersects the second direction D2.
[0129] As described above, except for the end portion 50, each corrugation channel 49 further includes a main body portion having large corrugations. In Figure 3 the main body portion is not shown.
[0130] Since the end points 65 of different corrugation channels 49 are aligned along the direction D3, the end portions 50 of the corrugation channels 25 all have different lengths, which are measured along the first direction D1.
[0131] More precisely, the end portions 50 of the corrugation channels 49 are juxtaposed along a third direction D3 perpendicular to the first direction D1. The first edge located at this juxtaposition ( Figure 3The end portion 50 on the upper edge (shown in the representation diagram) is the shortest. The length of the end portion 50 increases from the first edge to the second edge. In Figure 3 In the example shown, when moving from one corrugated channel 49 to another, the length increases by T1.
[0132] In other words, in Figure 3 In the example shown, the length difference between the end portions 50 of two adjacent corrugated channels 49 is T1.
[0133] In Figure 4 In the embodiment shown, the number of inclined channels 56 is less than the number of corrugated channels 49, and multiple corrugated channels 49 lead to the same inclined channel 56.
[0134] In Figure 4 In the example, the joining points 58 of the corrugated channels 49 leading to the same inclined channel 56 define the same projection point p on the straight line D.
[0135] Therefore, in Figure 4 In the example shown, the end portions 50 of the corrugated channels 49 leading to the same inclined channel 56 have the same length along the first direction D1.
[0136] The corrugated channels 49 leading to the same inclined channel 56 are adjacent to each other side by side along the third direction D3.
[0137] In Figure 4 In the example shown, the first separator 21 includes seven adjacent corrugated channels 49, and the corrugated channels 49 lead to each inclined channel 56.
[0138] In other examples of the embodiment, the number of inclined channels 56 is less than the number of corrugated channels 49, and multiple corrugated channels 49 lead to the same inclined channel 56, but the joining points 58 of the corrugated channels 49 leading to the same inclined channel 56 define at least two different projection points p on the straight line D.
[0139] In this case, the joining points 58 of the corrugated channels 49 leading to the same inclined channel 56 all define different projection points p on the straight line D. In one variant, the joining points 58 of some corrugated channels 49 define different projection points p on the straight line D, while the joining points 58 of other corrugated channels 49 define the same projection points p on the straight line D.
[0140] In this case, the lengths of the end portions 50 of the corrugated channels 49 with different projection points p are different in the first direction D1.
[0141] The corrugated channels 49 leading to the same inclined channel 56 are adjacent to each other side by side in the third direction D3, and the projection points p are continuous on the straight line D.
[0142] For example, two adjacent corrugated channels 49 lead to each inclined channel.
[0143] As Figure 4 shown, the wall 70 separating the inclined channels 56 has interruptions 72 through which the inclined channels 56 communicate with each other. Thus, the pressure between the inclined channels 56 can be balanced.
[0144] The second separator 23 also supports a channel network. The channel network may also include a plurality of corrugated channels for circulating the second reaction gas and a plurality of inclined channels.
[0145] In this case, the corrugated channels of the second separator may be similar to those of the first separator. Therefore, it will not be described in detail herein.
[0146] The inclined channels of the second separator may be similar to those of the first separator. Therefore, it will not be described in detail herein.
[0147] The junction points between the inclined channels and the corrugated channels may also define projection points on a straight line D parallel to the first direction, the projection being along the third direction, and these projection points being regularly spaced from each other along the first direction and separated from each other by a constant gap equal to a multiple of the period of the corrugations formed at the ends of the corrugated channels.
[0148] For example, the period is the same as the period of the corrugations at the ends of the channels of the first separator. In a variant, the periods are different.
[0149] Similarly, for example, the long period of the large corrugations of the corrugated channels of the second separator is equal to the long period of the corrugated channels of the first separator. In a variant, the long period of the large corrugations of the corrugated channels of the second separator is not equal to the long period of the corrugated channels of the first separator.
[0150] The fuel cell described above has several advantages.
[0151] When the projection points are separated from each other by a constant gap equal to a specific period of the corrugations, the projection points are as close as possible along the first direction. Thus, a very dense network of inclined channels can be drawn.
[0152] When each corrugated channel includes a main body portion extending along the first direction and forming large corrugations, and each large corrugation has a specific long period longer than the specific period of the corrugations at the ends, the risk of deformation of the channels of the first separator is reduced. The corrugated channels have a more pronounced shape change at the large corrugations, so that the main body portion of the corrugated channels provides better mechanical resistance when the separators are clamped against each other.
[0153] Set a number of inclined channels that is less than the number of corrugated channels, with multiple corrugated channels leading to the same inclined channel, which is beneficial to the manufacture of the first separator plate and limits the head loss in the inclined channels. Therefore, a large number of corrugated channels can be formed, thus ensuring a very uniform distribution of the first reaction gas in the central region of the plate.
[0154] Setting the junction points of the corrugated channels leading to the same inclined channel to define the same projection points on a straight line helps to make the inclined channel have an orientation substantially perpendicular to the first direction. This is advantageous for the layout of the channels on the first separator plate.
[0155] Since the ends of the corrugated channels have their respective tangents at their junction points and the tangents are all parallel to each other, the head loss of the first reaction gas passing through the junction point is substantially the same regardless of which corrugated channel is used.
[0156] The fuel cell described above has multiple variants.
[0157] In the above embodiment, the corrugated channels extend along a first direction D1 corresponding to the longitudinal direction L, that is, the direction corresponding to the long edge of the plate. In a variant, the first direction D1 does not coincide with the longitudinal direction L but forms an angle with the longitudinal direction L.
[0158] The inclined channels are not necessarily channels belonging to the distribution region 40 or the distribution region 42. The inclined channels can be formed on the central region 38 of the plate.
[0159] The first separator plate 21 does not necessarily contact the catalyst layer forming the anode. The first separator plate 21 can contact the catalytic layer forming the cathode.
[0160] The second separator plate is not necessarily of the same type as the first separator plate. As described above, only one of the two separator plates can carry the corrugated channels and the inclined channels, and the junction points of the corrugated channels and the inclined channels are regularly spaced along the first direction.
[0161] The corrugated channels do not necessarily have a straight centerline. The centerline can have sections with different orientations.
Claims
1. A separator plate for an electrochemical cell of a fuel cell (1), the separator plate (21) comprising on a first side: a plurality of corrugated channels (49) for circulating a first reaction gas, the plurality of corrugated channels (49) having respective ends (50), the ends (50) all extending along the same first direction (D1) and forming corrugations having the same specific period (T1); and a plurality of inclined channels (56), each of the plurality of inclined channels (56) extending along a second direction (D2) intersecting the first direction (D1), each end (50) of each of the plurality of corrugated channels (49) being connected to one of the plurality of inclined channels (56) at a junction point (58); the junction point (58) defining a projection point (p), the projection point (p) being projected onto a straight line (D) parallel to the first direction (D1), the projection being performed in a third direction (D3) perpendicular to the first direction (D1), the projection points (p) being regularly spaced from each other along the first direction (D1) and separated from each other by a constant gap equal to a multiple of the specific period (T1).
2. The spacer according to claim 1, wherein, The projection points (p) are separated from each other by a constant gap equal to the specific period (T1).
3. The spacer according to any one of the preceding claims, wherein, Each of the corrugated channels (49) includes a body portion (62) extending along the first direction (D1) and forming a large corrugation having a specific long period (T2), the specific long period (T2) being greater than the specific period (T1) of the corrugations of the ends (50), the ends (50) of the corrugated channels (49) extending between the body portion (62) and the junction point (58) of the corrugated channels (49).
4. The partition board according to any one of the preceding claims, wherein, The number of the inclined channels (56) is less than the number of the corrugated channels (49), and a plurality of corrugated channels (49) lead to the same one of the inclined channels (56).
5. The spacer according to claim 4, wherein, The junction points (58) of the plurality of corrugated channels (49) leading to the same one of the inclined channels (56) define the same projection point (p) on the straight line (D).
6. The spacer according to claim 4, wherein, The junction points (58) of the plurality of corrugated channels (49) leading to the same one of the inclined channels (56) define at least two different projection points (p) on the straight line (D).
7. The spacer according to any one of claims 1 to 4 and 6, wherein, The junction point (58) is located on a straight line (C’) intersecting the first direction (D1).
8. The spacer according to any one of the preceding claims, wherein, The ends (50) of the plurality of corrugated channels (49) have respective tangents (T) at their junction points (58), and the tangents (T) are all parallel to each other.
9. The spacer according to any one of the preceding claims, wherein, The inclined channels (56) have inclined ends (60) connected to the junction points (58), and the inclined ends (60) are straight lines and parallel to each other.
10. The spacer according to claim 9, wherein, The inclined ends (60) extend along the third direction (D3) perpendicular to the first direction (D1).
11. A fuel cell (1) comprising a plurality of fuel cells, each of the fuel cells comprising: An electrolyte membrane (3), the electrolyte membrane (3) having a first major surface (5) and a second major surface (7) facing each other; A first catalyst layer (9) and a second catalyst layer (11), the first catalyst layer (9) and the second catalyst layer (11) being arranged against the first major surface (5) and the second major surface (7) of the electrolyte membrane (3); A separator (21) according to any one of the preceding claims, the first catalyst layer (9) being arranged between a first surface of the separator (21) and the electrolyte membrane (3).