Guide and polar plate for a polar separator of an electrochemical cell, separator comprising such a guide and polar plate, and fuel cell comprising such a separator

Abstract

The invention relates to a guide (50C) for a polar separator of an electrochemical cell, which guide comprises walls (52H; 52C) arranged side-by-side along a surface plane (P11H; P11C), so as to define channels (57C) for guiding the functional fluid, each channel being defined by and between two walls. Each wall comprises an application surface (63C) which is coplanar with the surface plane and via which the wall bears against a receiving surface (41H). The guide comprises an anchoring mat (51C) interconnecting the walls. The walls and the anchoring mat together form a single monolithic piece made of joint material. The anchoring mat extends from the walls beyond the surface plane, so that it can be housed in an anchoring cavity, in order to anchor the guide (50C) received at the receiving location.

Description

[0001] TITLE: Guide and polar plate for an electrochemical cell polar separator, separator comprising such guide and polar plate, and fuel cell comprising such a separator

[0002] The invention relates to a guide and a polar plate for a polar separator of an electrochemical cell. The invention also relates to a polar separator comprising the guide and the polar plate, as well as to a fuel cell comprising an electrochemical cell comprising the polar separator.

[0003] A fuel cell is known which comprises a stack of polar components and membrane-electrode assemblies to form electrochemical cells for producing electricity by chemical reaction between two functional fluids, namely hydrogen and air, through a proton exchange membrane formed on each membrane-electrode assembly. To conduct each functional fluid to the proton exchange membrane and evacuate the reaction products, each polar separator comprises a polar plate which has a face bearing against the membrane-electrode assembly. The polar plate has two distribution orifices, one for conveying the functional fluid to the face, the other for evacuating the reaction products formed along the face.Between these two distribution ports, the face forms a circulation field, extending along the membrane and fluidically connecting the distribution ports, to bring the functional fluid into contact with the membrane and collect the reaction products. Between each distribution port and the circulation field, the face forms a routing field, sometimes called a homogenization zone, to connect the circulation field to the relevant distribution port. The first routing field is intended to distribute the functional fluid from the distribution port over the entire surface of the circulation field. The second routing field is intended to collect the unconsumed functional fluid and reaction products from the circulation field and direct them to the other distribution port.The polar separator also includes a seal, interposed between the polar plate and the membrane-electrode assembly, so that the functional fluid circulating along the face of the polar plate does not escape through the periphery of the plates.

[0004] The routing field forms channels on the face of the polar plate, which are obtained by stamping the polar plate. A disadvantage of forming the channels of the routing field by stamping is that, on the opposite face of the polar plate, a negative of these channels is also formed. This constraint limits the possibilities of forming other elements on the opposite face of the polar plate, in particular other channels for the routing of a coolant between two successive polar plates. Another solution would be to form the channels of the routing field by another method, such as machining the polar plate, but these other methods may prove industrially less efficient and more expensive than stamping the polar plate.

[0005] Therefore, the invention aims in particular to solve these drawbacks of the prior art and to propose a new solution for easily forming a polar separator which has a routing field on one plate face of a polar plate, minimizing the impact on an opposite plate face of the polar plate and without prejudice to the mechanical characteristics of the routing field.

[0006] According to a first aspect, the subject of the invention is a guide for a polar separator of an electrochemical cell, the guide being configured to be received on a receiving location belonging to a plate face of a polar plate belonging to the polar separator, in order to form a routing field on the plate face, capable of guiding a functional fluid along the plate face, the guide comprising: walls, which are arranged side by side along a surface plane, so as to delimit channels for guiding the functional fluid, the channels being arranged side by side along the surface plane, each channel being delimited between, and by, two of said walls, each wall comprising an application surface, which is coplanar with the surface plane and by means of which the wall is designed to bear on a receiving surface belonging to the receiving location,when the guide is received at the receiving location; and an anchoring mat, connecting the low walls together, such that the low walls and the anchoring mat together constitute a single monolithic piece of joint material, the anchoring mat extending from the low walls beyond the surface plane, so as to be able to be housed in an anchoring cavity belonging to the receiving location, formed in a hollow from the receiving surface, in order to anchor the guide at the receiving location when the guide is received at the receiving location.,

[0007] One idea underlying the invention is to provide for forming the routing field of the polar separator by combining the guide made of seal material, for example an elastomer, with a receiving location formed by the polar plate, the polar plate being for example made of metal.

[0008] To ensure good mechanical strength of the guide on the receiving location, the guide is anchored on the receiving location using the anchoring mat, housed in the anchoring cavity. This also minimizes a risk of migration of the guide tangentially along the surface during the manufacture of the electrochemical cell or during its use. Outside of the anchoring mat, the walls each comprise an application surface which bears on the receiving surface. The anchoring mat advantageously allows the guide to be formed in a single operation, for example by overmolding the guide directly at the receiving location, or by molding the guide before attaching it to the receiving location, since the anchoring mat connects the walls together and allows the guide to be formed in a single overmolding or in a single mold.

[0009] According to other advantageous aspects of the invention, the guide comprises one or more of the following characteristics, taken individually or in all technically possible combinations:

[0010] - Each wall includes:

[0011] - a primary end, each channel comprising a primary inlet bordered by two of the primary ends;

[0012] - a secondary end, each channel comprising a secondary inlet bordered by two of the secondary ends; and

[0013] - a main part, which connects the primary end to the secondary end, to guide the functional fluid between the primary inlet and the secondary inlet of the channel delimited by said wall.

[0014] - For at least one of the low walls, the primary end forms a bracing pad, widened in relation to the main part.

[0015] - For at least one of the walls, the primary end and the main part are of equal width.

[0016] - For at least one of the walls, the secondary end and the main part are of equal width.

[0017] - For at least one of the walls, the primary end is arranged, along the surface plane, beyond the anchoring mat, and comprises a portion of the application surface, such that said primary end is designed to bear on the receiving surface via the portion of the application surface when the guide is received on the receiving location.

[0018] - For at least one of the walls, the primary end is arranged, following the surface plane, in the anchor mat so as not to come to bear on the receiving surface when the guide is received on the receiving location.

[0019] - The secondary ends are further apart from each other than the primary ends. According to a second aspect, the invention also relates to a polar plate, for a polar separator of an electrochemical cell, the polar plate comprising a plate face, parallel to a surface plane, and a first distribution orifice passing through the polar plate from the plate face, the plate face comprising: an injection rim, delimiting the first distribution orifice; a circulation field;and a receiving location, formed by the plate face and connecting the injection rim to the circulation field, so that a functional fluid can circulate from the circulation field to the first distribution orifice or vice versa, by circulating on the surface of the plate face via the receiving location and the injection rim, the receiving location being configured to receive a guide belonging to the polar separator, in order to form, with said guide, a routing field arranged between the circulation field and the injection rim, to guide the functional fluid on the surface of the plate face from the circulation field to the injection rim or vice versa, the receiving location comprising:;

[0020] • a receiving surface, which is coplanar with the surface plane and which is designed to receive walls belonging to the guide, the receiving surface being configured so that each wall bears against the receiving surface via a respective application surface belonging to said wall, when the guide is received at the receiving location; and

[0021] • an anchoring cavity, which is formed as a recess beyond the surface plane from the receiving surface and which is designed to accommodate an anchoring mat belonging to the guide and connecting the walls together, in order to anchor the guide to the receiving location when the guide is received on the receiving location.

[0022] With respect to the polar plate, forming the anchoring cavity is generally simpler than forming walls and channels directly by stamping, and has less impact on an opposite plate face of the polar plate, particularly in the case where it is intended to form the anchoring cavity by stamping. Indeed, the shape of the anchoring cavity may be designed not to occupy the entire area of ​​the routing field, so that a cavity back formed on the opposite face occupies less space than that which would be occupied by the back of a routing field which would be entirely formed by stamping the plate face. According to other advantageous aspects of the invention, the polar plate comprises one or more of the following features, taken individually or in all technically possible combinations:

[0023] - The anchoring cavity has an edge which extends parallel to the injection rim, along the injection rim for at least 50%, preferably for at least 80%, of a length of the injection rim, the length of the injection rim being measured along the surface plane.

[0024] - The polar plate comprises a second distribution orifice passing through the polar plate from the plate face; and the plate face comprises an anchoring cavity back which projects from the surface plane and which is arranged between the receiving location, the second distribution orifice, the circulation field and the first distribution orifice.

[0025] According to a third aspect, the invention also relates to a polar separator, for an electrochemical cell, the polar separator comprising the guide as described previously and the polar plate as described above and the guide being received at the receiving location, with the application surface of the walls resting on the receiving surface and with the anchoring mat housed in the anchoring cavity, so that the receiving location forms, with the guide, the routing field, arranged between the circulation field and the injection rim, to guide the functional fluid on the surface of the plate face, from the circulation field to the injection rim or vice versa.

[0026] Preferably, a method of manufacturing the aforementioned polar separator first comprises providing or manufacturing the aforementioned polar plate, and forming the guide in situ, directly on the plate face, at the receiving location, for example by overmolding the guide. Preferably in this case, the peripheral seal is also formed by overmolding the peripheral seal onto the plate face, so that the guide and the peripheral seal are formed during the same overmolding, with the same overmolding.

[0027] Alternatively, it is planned to supply or manufacture the polar plate and the guide separately from each other, and then to bring the guide back to the receiving location of the polar plate.

[0028] According to other advantageous aspects of the invention, the polar separator comprises one or more of the following characteristics, taken individually or in all technically possible combinations:

[0029] - Perpendicular to the surface plane, the anchor mat is fully received in the anchor cavity so as not to protrude from the surface plane. - The polar separator further comprises a peripheral seal, which is received on the plate face, forming a main closed loop around the circulation field and the routing field, in order to maintain the functional fluid circulating along the plate face within the main closed loop; and the receiving location and the guide are arranged within the main closed loop.

[0030] - The guide belongs to the peripheral seal, while the guide is attached to the main closed loop by means of a tab belonging to the peripheral seal, the peripheral seal constituting a single monolithic piece of seal material, including both the guide and the main closed loop.

[0031] - The injection rim comprises a row of injection ports, such that the functional fluid flowing on the surface of the plate face via the injection rim passes through the polar plate via the injection ports to reach the first distribution port, or such that the functional fluid flowing in the first distribution port passes through the polar plate via the injection ports of the injection rim to reach the plate face, at the injection rim; the main closed loop comprises a rim portion received on the injection rim, between the first distribution port and the row of injection ports; and the anchoring cavity is arranged between the row of injection ports and the circulation field.

[0032] - The main closed loop surrounds the distribution port and the injection rim so that the functional fluid can flow from the injection rim to the first distribution port and vice versa along the plate face, without crossing the pole plate.

[0033] According to a fourth aspect, the invention also relates to a fuel cell, comprising electrochemical cells, at least one of the electrochemical cells comprising: the polar separator as described above, which constitutes a first polar separator; a second polar separator;and a membrane-electrode assembly, comprising an exchange zone which includes a proton exchange membrane, the first polar separator, the membrane-electrode assembly and the second polar separator being superimposed in a stacking direction, such that the membrane-electrode assembly is interposed between the first polar separator and the second polar separator, the peripheral seal of the first polar separator being interposed between the polar plate of the first polar separator and the membrane-electrode assembly, the circulation field of the polar plate of the first polar separator bearing against the exchange zone in the stacking direction.;

[0034] The invention will appear more clearly on reading the description which follows, given solely by way of non-limiting example, and made with reference to the drawings in which:

[0035] [Fig. 1] Figure 1 is a perspective view of a fuel cell according to one embodiment of the invention;

[0036] [Fig. 2] Figure 2 is an exploded perspective view of an electrochemical cell belonging to the fuel cell of Figure 1;

[0037] [Fig. 3] Figure 3 is a partial front view of a polar separator, showing a first plate face;

[0038] [Fig. 4] Figure 4 is a perspective of the polar separator of Figure 3, cut along the section line IV-IV shown in Figure 3;

[0039] [Fig. 5] Figure 5 is a partial back view of the polar separator of Figures 3 and 4, showing a second plate face;

[0040] [Fig. 6] Figure 6 is a perspective of the polar separator of the preceding figures, cut along the section line VI-VI shown in Figure 5.

[0041] Figure 1 shows a fuel cell 1, comprising a stack 2 of electrochemical cells 4, as well as two terminal plates 3. The fuel cell 1 is preferably intended to equip a vehicle, in particular to electrically power an electric motor intended for traction or propulsion of the vehicle.

[0042] Stack 1 defines a longitudinal direction X, a transverse direction Y and a stacking direction Z. As illustrated, each of these directions X, Y and Z is oriented, that is to say it is directed in a direction symbolized by an arrow in the figures. These directions are perpendicular to each other and distinct. Preferably, the transverse direction Y is directed upwards when the stack is in use.

[0043] The stack 2 is interposed between the two end plates 3 along the stacking direction Z and is sandwiched between said end plates 3. The stack 2 is supplied, advantageously via one of the end plates 3, with a primary reactive fluid, a secondary reactive fluid and, preferably, a cooling fluid. Each of these fluids is a functional fluid. The primary reactive fluid and the secondary reactive fluid react chemically within each cell 4 of the stack 2 to generate electricity. The primary and secondary reactive fluids, loaded with reaction products, and the cooling fluid heated by the stack 2, are also discharged from the stack 2, for example via the same end plate 3. The primary reactive fluid may be an anodic fluid, preferably a gas containing hydrogen.The secondary reactive fluid may be a cathode fluid, preferably an oxygen-containing gas, such as air. Alternatively, the primary reactive fluid is the cathode fluid while the secondary reactive fluid is the anodic fluid. The cooling fluid is advantageously a coolant.

[0044] The stack 2 can comprise several hundred electrochemical cells 4. As shown in FIG. 2, each electrochemical cell 4 comprises, successively along the stacking direction Z, a polar separator 5, a membrane-electrode assembly 90, and a polar separator 105.

[0045] Within each cell 4 a chemical reaction occurs between the primary and secondary reactive fluids, creating an electrical potential difference between the polar separator 5 and the polar separator 105. Here, for each cell 4, the polar separator 5 is an anodic separator while the polar separator 105 is a cathodic separator, but the reverse could be expected.

[0046] The membrane-electrode assembly 90 has a general plate shape, which extends along a plane perpendicular to the stacking direction Z. The membrane-electrode assembly 90 is superimposed with the polar separator 5 of the same cell 4, along the stacking direction Z, that is to say that the membrane-electrode assembly 90 and the polar separator 5 are stacked along the direction Z, in particular with superposition of their respective contours. Thus superimposed, the membrane-electrode assembly 90 is arranged in the stacking direction Z relative to the polar separator 5. The polar separator 105 is superimposed with the membrane-electrode assembly 90 of the same cell 4 along the stacking direction Z, that is to say that the membrane-electrode assembly 90 and the polar separator 105 are stacked along the direction Z, in particular with superposition of their respective contours.Thus superimposed, the polar separator 105 is arranged in the stacking direction Z relative to the membrane-electrode assembly 90 and relative to the polar separator 5 of the same cell 4. In other words, for each cell 4, the membrane-electrode assembly 90 is interposed between the polar separator 5 and the polar separator 105 along the direction Z. In addition, the polar separator 105 of a preceding cell 4 of the stack 2 is superimposed with the separator 5 of the following cell 4, along the stacking direction Z, and so on.

[0047] The membrane-electrode assembly 90 has a face 91, facing in the opposite direction to the stacking direction Z in the direction of the immediately adjacent polar separator 5, belonging to the same cell 4. The membrane-electrode assembly 90 has a face 92, facing in the direction Z in the direction of the immediately adjacent polar separator 105. The membrane-electrode assembly 90 comprises a peripheral zone 97 and an exchange zone 93, surrounded by the peripheral zone. The face 91 is formed by the peripheral zone 97 and the exchange zone 93. The face 92 is also formed by the peripheral zone 97 and the exchange zone 93, opposite in the direction Z.

[0048] Preferably, the membrane-electrode assembly 90 is symmetrical in shape around an axis of symmetry parallel to the Z direction.

[0049] The exchange zone 93, comprising a proton exchange membrane, which is advantageously covered, on the side of the face 91, by a gas diffusion layer, and on the side of the face 92, by another gas diffusion layer, belonging to the exchange zone 93. The membrane is therefore interposed between the two gas diffusion layers. Preferably, the entire area of ​​the exchange zone 93, or almost the entire area, is occupied by the proton exchange membrane. Preferably, the entire area of ​​the exchange zone 93, or almost the entire area, is occupied by the gas diffusion layers.

[0050] The peripheral zone 97 forms an outer contour of the assembly 90. The peripheral zone 97 is coplanar with the exchange zone 93, in particular with the membrane, extending in a plane perpendicular to the Z direction.

[0051] The peripheral zone 97 may be made of the same material as the proton exchange membrane, extending said membrane beyond the gas diffusion layers if they are provided, so that the peripheral zone 97 is not covered by the gas diffusion layers. Alternatively, the peripheral zone 97 is constituted by a holding frame, which surrounds the membrane over its entire periphery and is assembled with said membrane. The holding frame is for example formed by two polymer films superimposed along the stacking direction Z. The gas diffusion layers, if they are provided, may locally cover the holding frame, that is to say extend slightly beyond the membrane, at the boundary between the membrane and the holding frame.

[0052] The membrane-electrode assembly 90 also comprises distribution orifices 95H, 96H, 950, 960, 95C and 96C, arranged through the peripheral zone 97. Each orifice 95H, 96H, 950, 960, 95C and 96C connects the face 91 to the face 92.

[0053] The orifice 95H is a feed orifice, which belongs to a feed gallery formed through the stack 2 in the Z direction and which is configured to be traversed, in the Z direction, by the primary reactive fluid, to feed the stack 2. As such, the orifice 95H is itself traversed by the primary reactive fluid. The orifice 96H is an evacuation orifice, which belongs to a evacuation gallery formed through the stack 2 in the Z direction and which is configured to be traversed, in the Z direction, by a mixture of primary reactive fluid and reaction products originating from the stack 2. As such, the orifice 96H is itself traversed by the mixture. The orifices 95H and 96H are arranged on either side of the exchange zone 93.

[0054] The orifice 950 is a feed orifice, which belongs to a feed gallery formed through the stack 2 in the Z direction and which is configured to be traversed, in the Z direction, by the secondary reactive fluid, to feed the stack 2. As such, the orifice 950 is itself traversed by the secondary reactive fluid. The orifice 960 is an evacuation orifice, which belongs to a evacuation gallery formed through the stack 2 in the Z direction and which is configured to be traversed, in the Z direction, by a mixture of secondary reactive fluid and reaction products originating from the stack 2. As such, the orifice 960 is itself traversed by the mixture. The orifices 950 and 960 are arranged on either side of the exchange zone 93.

[0055] The orifice 950 is a supply orifice, which belongs to a supply gallery formed through the stack 2 in the Z direction and which is configured to be traversed, in the Z direction, by the cooling fluid, to supply the stack 2. As such, the orifice 950 is itself traversed by the cooling fluid. The orifice 960 is an evacuation orifice, which belongs to an evacuation gallery formed through the stack 2 in the Z direction and which is configured to be traversed, in the Z direction, by cooling fluid coming from the stack 2. As such, the orifice 960 is itself traversed by the cooling fluid. The orifices 950 and 960 are arranged on either side of the exchange zone 93.

[0056] The polar separator 105 comprises a plate face 1110, by means of which it is superimposed on the membrane-electrode assembly 90, against the face 92, and an opposite plate face 1110. The faces 1110 and 1110 are opposite and perpendicular to the Z direction. The polar separator 105 comprises distribution orifices 115H, 116H, 1150, 1160, 1150 and 1160, each distribution orifice passing through the separator 105 by connecting the plate face 1110 to the plate face 1110. The orifices 115H, 116H, 1150, 1160, 1150 and 1160 are respectively superimposed with the orifices 95H, 96H, 950, 960, 950 and 960 of the membrane electrode assembly 90 in the Z direction, to extend the galleries formed by the orifices 95H, 96H, 950, 960, 950 and 960 and be crossed by the same functional fluids.

[0057] The polar separator 5 comprises a polar plate 10, with a first plate face 11 H, facing in the Z direction and shown in more detail in Figures 5 and 6. The polar plate 10 comprises a second plate face 110 opposite the first plate face 11 H, facing in the opposite direction to the Z direction and shown in more detail in Figures 3 and 4. Preferably, the polar separator 5, or at least the polar plate 10, is symmetrical in shape around an axis of symmetry parallel to the Z direction.

[0058] Preferably, the polar plate 10 is formed in one piece from a sheet or metal plate. The polar plate 10 is advantageously made of electrically conductive metal, such as aluminum or stainless steel, but may alternatively be made of graphite. Preferably, the polar plate 10 has been obtained entirely by stamping the sheet or metal plate. Alternatively or additionally, the plate 10 may have been machined.

[0059] The plate face 11 H extends, generally, along a surface plane P11 H, shown in Figures 4 and 6 and being perpendicular to the Z direction. The plate face 11 C extends, generally, along a surface plane P11 C, shown in Figures 4 and 6 and being perpendicular to the Z direction and parallel to the plane P11 H.

[0060] The polar plate 10 comprises distribution orifices 15H, 16H, 15C, 16C, 150 and 160, each distribution orifice passing through the plate 10 by connecting the plate face 11H to the plate face 11C. In particular, each orifice 15H, 16H, 15C, 16C, 150 and 160 connects a peripheral zone 23H belonging to the face 11H to a peripheral zone 23C belonging to the face 11C. Preferably, the orifices 15H, 150 and 150 are arranged at one end of the plate 10 along the direction X, while the orifices 16H, 16C and 160 are arranged at an opposite end. The orifice 150 is preferably arranged between the orifices 15H and 150, along the Y direction. The orifice 15H is preferably positioned in the Y direction relative to the orifices 150 and 150. The orifice 160 is preferably arranged between the orifices 160 and 16H, along the Y direction. The orifice 160 is preferably positioned in the Y direction relative to the orifices 160 and 16H.

[0061] The orifices 15H, 16H, 150, 160, 150 and 160 are respectively superimposed with the orifices 95H, 96H, 950, 960, 950 and 960 of the membrane electrode assembly 90 in the Z direction.

[0062] Port 15H is a feed port, which belongs to the same feed gallery as port 95H. As such, port 15H is itself crossed by the primary reactive fluid. Port 16H is an exhaust port, which belongs to the same exhaust gallery as port 96H. As such, port 16H is itself crossed by the mixture.

[0063] The orifice 150 is a supply orifice, which belongs to the same supply gallery as that of the orifice 950. As such, the orifice 150 is itself crossed by the secondary reactive fluid. The orifice 160 is an evacuation orifice, which belongs to the same evacuation gallery as the orifice 960. As such, the orifice 160 is itself crossed by the mixture. Alternatively, the supply of cathodic fluid, that is to say air, takes place via the orifice 160 and the orifice 150 is an evacuation orifice. In other words, the orifices 150 and 160 can be indifferently reversed in their functions of conveying or evacuating gases.

[0064] The orifice 150 is a supply orifice, which belongs to the same gallery as that of the orifice 950. As such, the orifice 150 is itself crossed by the cooling fluid. The orifice 160 is an evacuation orifice, which belongs to the same evacuation gallery as that of the orifice 960. As such, the orifice 160 is itself crossed by the cooling fluid.

[0065] Alternatively, the coolant supply takes place via the orifice 160 and the orifice 150 is an exhaust orifice. In other words, the orifices 150 and 160 can be indifferently reversed in their functions of conveying or exhausting gases.

[0066] The polar plate 10 is described here in more detail concerning the plate face 11 H, in connection with figures 2, 5 and 6.

[0067] The plate face 11 H comes opposite the face 91 of the membrane electrode assembly 90 of the same cell 4 of the stack 2.

[0068] On the side of the plate face 11 H, the polar plate 10 mainly comprises a circulation field 20 H, two routing fields 21 H and 22 H, the aforementioned peripheral zone 23 H, a peripheral seal 24 H and two injection edges 25 H and 26 H. Two anchoring cavity backs 27 H and 28 H can advantageously be provided.

[0069] The peripheral zone 23H is formed directly by the face 11H of the polar plate 10. The peripheral zone 23H frames the circulation field 20H, the routing fields 21H and 22H and the injection edges 25H and 26H. The peripheral zone 23H has a frame shape, forming a closed loop which entirely forms a peripheral contour of the face 11H and the plate 10, for example of generally rectangular shape.

[0070] The circulation field 20H is preferably arranged in the center of the face 11 H. Along the X direction, the circulation field 20H is arranged between the routing fields 21 H and 22 H, arranged at opposite ends of the circulation field 20H.

[0071] Along the X direction, the routing field 21H is arranged between the orifices 15H, 15C and 150 and the circulation field 20H. In particular, the circulation field 20H starts at one end of the routing field 21H. At an opposite end of the routing field 21H, the injection rim 25H, belonging to the peripheral zone 23H, connects the orifice 15H to the routing field 21H. The cavity back 27H is arranged so as to be adjacent to the routing field 21H and the orifices 15C and 150. Along the X direction, the routing field 22H is arranged between the circulation field 20H and the orifices 16H, 16C and 160, which are adjacent to the routing field 22H. In particular, the circulation field 20H ends at one end of the routing field 22H. At an opposite end of the routing field 22H, the injection rim 26H, belonging to the peripheral zone 23H, connects the routing field 22H to the orifice 16H.The cavity back 28H is arranged to be adjacent to the routing field 22H and the ports 16C and 160.

[0072] The polar separator 5 is configured so that the primary reactive fluid circulating in the orifice 15H is admitted between the face 11H and the face 91 via the injection rim 25H, then is discharged through the orifice 16H via the injection rim 26H. In doing so, the primary reactive fluid circulates along the face 11H, successively along the injection rim 25H, the routing field 21H, the circulation field 20H, the routing field 22H, the injection rim 26H.

[0073] Each injection rim 25H and 26H is preferably formed directly by the face 11H. Preferably, each injection rim 25H and 26H comprises a row of injection orifices, which connect the faces 11H and 11C together. Preferably, each injection rim 25H and 26H extends along the plane P11H, at least at the location of the injection orifices, and preferably, from each injection orifice to the adjacent routing field. As shown in Figure 5, the injection rim 25H comprises injection orifices 29H, for example arranged along a line which extends along the distribution orifice 15H. The injection orifices of the injection rim 26H are arranged in a similar manner along the distribution orifice 16H.

[0074] The primary reactive fluid admitted to the surface of the plate face 11 H from the orifice 15 H, first circulates along the face 11 C, from the orifice 15 H to the orifices 29 H, then passes through the plate 10 via the orifices 29 H to reach the face 11 H at the injection rim 25 H, to then reach the routing field 21 H from the injection rim 25 H. The primary reactive fluid to be discharged from the face 11 H to the orifice 16 H, reaches the rim 26 H from the routing field 22 H, passes through the injection orifices of the rim 25 H to pass from the face 11 H to the face 11 C, then is discharged through the orifice 16 H on the side of the face 11 C.

[0075] The peripheral seal 24H, shown in dotted lines in Figure 2 and shown in more detail in Figure 5, is received on the plate face 11H, in particular is entirely received on the peripheral zone 23H. Preferably, over the entire part of the peripheral zone 23H receiving the seal 24H, said seal 24H extends along the face plane P11H. Along the direction Z, the seal 24H comes into contact with the face 91 of the membrane-electrode assembly 90, in particular with the peripheral zone 97. The seal 24H thus delimits zones sealed against functional fluids, between the faces 11H and 91, preventing said functional fluids from escaping peripherally.

[0076] The 24H peripheral seal is preferably formed in one piece. The 24H peripheral seal is made of a seal material, i.e., for example, an elastomer. The 24H peripheral seal is preferably obtained by overmolding said 24H seal directly onto the 11H face, or alternatively onto the 91 face. Alternatively, the 24H seal may be manufactured separately and then attached to the 11H face, or alternatively to the 91 face.

[0077] The peripheral seal 24H comprises a main closed loop 31H, formed on the face 11H, or at least interposed between the face 11H and the face 91. The main closed loop 31H has the function of maintaining the primary reactive fluid circulating along the face 11H inside the main loop 31H, between the faces 11H and 91. On the side of the face 11H, the main closed loop 31H surrounds at least the circulation field 20H and the routing fields 21H and 22H. On the side of the face 91, the closed loop surrounds the exchange zone 93.

[0078] It is advantageously provided that the ports 15H, 15C, 150, 16H, 160 and 160 are arranged outside the main closed loop 31H, as shown in FIG. 5 for the ports 15H, 150 and 150, since the injection rims 25H and 26H comprise injection ports. Similarly, the orifices 95H, 950, 950, 96H, 960 and 960 are arranged outside the main closed loop 31H. As shown for the injection orifices 29H in FIG. 5, the injection orifices of the injection rims 25H and 26H are arranged inside the main loop 31H. Consequently, all the primary reactive fluid circulating on the surface of the face 11H is surrounded by the main loop 31H, preventing said primary reactive fluid from escaping at the periphery of the face 11H. More precisely, the main closed loop 31H comprises, for each injection rim 25H and 26H, a respective rim portion.For the injection rim 25H, this is a rim portion 32H shown in Figure 5. Each rim portion is received on the plate face 11H just like the rest of the main loop 31H. The rim portion 32H is received on the injection rim 25H, between the distribution orifice 15H and the row of injection orifices 29H, in order to separate the orifice 15H from the orifices 29H. Similarly, the other rim portion is received on the injection rim 26H, between the distribution orifice 16H and the row of injection orifices of this injection rim 26H, in order to separate the orifice 16H from said injection orifices.

[0079] Preferably, when the injection rim comprises injection orifices, the peripheral seal 24H also comprises spacer pads received on the injection rim, on the face 11 H, inside the main loop 31 H. Each spacer pad bears against the face 91 in the direction Z, so as to be interposed between the faces 11 H and 91. Each injection pad advantageously extends from the injection part of the seal 24H, in the direction of the routing field, being arranged between two successive injection orifices. Each injection pad is preferably formed in one piece with the main loop 31 H. For example, as shown in FIG. 5, spacer pads 36H are provided, which extend from the edge portion 32H, towards the field 21 H. At the location of the spacer pads, the injection edge preferably extends along the surface plane P11 H.

[0080] Preferably, the peripheral seal 24H comprises secondary closed loops, each surrounding one of the distribution orifices and being received on the plate face 11H. Each secondary closed loop comes into contact with the face 91 in the Z direction, so as to be interposed between the face 11H and the face 91. Preferably, each secondary loop is formed in one piece with the main loop 31H. Preferably, each orifice 15H, 15C, 150, 16H, 16C and 160 is surrounded by a respective secondary closed loop belonging to the seal 24H. Each secondary loop also being in contact with the face 91, each orifice 95H, 95C, 950, 96H, 96C and 960 is also surrounded by one of the respective secondary loops. Each secondary loop therefore connects, in the Z direction, one of the orifices 15H, 15C, 150, 16H, 16C and 160 to the orifice 95H, 95C, 950, 96H, 96C or 960 which is superimposed on it, to form the corresponding gallery.Each secondary loop thus ensures that the functional fluid circulating in the gallery concerned does not escape outside cell 4, nor towards the inside of the main loop 31 H, except in the presence of one of the injection edges, as is the case for orifices 15H and 16H.

[0081] As shown in Figure 5, in particular, a secondary closed loop 33H surrounds the orifice 15H, a secondary closed loop 34H surrounds the orifice 15C and a secondary closed loop 35H surrounds the orifice 150. As shown in Figure 5, the secondary closed loops 33H, 34H and 35H and the main loop 31H advantageously have common parts. For example, the main loop 31H and the secondary loop 33H have in common the rim part 32H. The same considerations apply to the secondary loops surrounding the orifices 16H, 16C and 160 respectively.

[0082] Preferably, no portion of the 24H seal subdivides the closed loop(s) into multiple closed loops formed by the 24H seal.

[0083] Preferably, the circulation field 20H is formed directly by the plate face 11 H. Preferably, the circulation field 20H has a generally rectangular shape in the X and Y directions. The circulation field 20H comprises walls, which are in relief in the Z direction relative to the face plane P11 H. Preferably, each wall connects the two ends of the circulation field 20H together in the X direction, i.e. extends from the field 21 H to the field 22 H. The walls are arranged side by side so as to delimit channels between them, each channel being arranged between two successive walls. Between two successive walls, the channel is delimited by a channel bottom formed by the face 11 H, preferably in the plate plane P11 H. Each channel connects the field 21 H to the field 22 H. Preferably, the circulation field 20H is formed by stamping the plate 10, the stamping making it possible to obtain the raised walls and channels.

[0084] Along the Z direction, the circulation field 20H, in particular each wall, comes to bear against the exchange zone 93 of the membrane electrode assembly 90, being superimposed with the exchange zone 93. Preferably, the circulation field 20H bears against the exchange zone 93 over its entire surface, or the exchange zone 93 bears against the circulation field 20H over its entire surface.

[0085] The primary reactive fluid flowing along the face 11H is admitted along the circulation field 20H from the routing field 21H, and flows to the opposite end of the circulation field 20H via the channels of said circulation field 20H, being guided by said channels and being distributed over said channels. At the opposite end of the circulation field 20H, the primary reactive fluid is admitted into the routing field 22H. During its circulation along the field 20H, the primary reactive fluid comes into contact with the exchange zone 93, where the reaction takes place through the proton exchange membrane, generating an electrical potential difference between the separators 5 and 105.

[0086] As shown in Figures 5 and 6, the routing field 21 H is formed in part by a receiving location 40H formed by the plate face 11 H, that is to say formed directly by the plate 10. Another part of the routing field 21 H is formed by a guide 50H, which is a part separate from the plate 10, added or applied to the face of the plate 11 H, in particular, received on the receiving location 40H.

[0087] Preferably, the receiving location 40H is formed entirely by the face 11 H. The receiving location 40H connects the injection rim 25H, over an entire length L25H of the injection rim 25H, to the circulation field 20H, over the entire width of the circulation field 20H in the direction Y. In other words, the location 40H occupies the entire area of ​​the routing field 21 H. The length L25H is measured along the plane P11 H. Preferably, the length L25H is measured from the first injection orifice 29H to the last injection orifice 29H. In the absence of injection orifices, the length L25H is preferably measured along the contour of the orifice 15H, from a first part of the main closed loop 31 H to another part of the main closed loop 31 H, connected by the injection rim.

[0088] The receiving location 40H comprises a receiving surface 41H and an anchoring cavity 42H, best seen in Figure 6. The receiving surface 41H and the anchoring cavity 42H are formed directly by the face 11H.

[0089] Opposite the X direction, the receiving surface 41 H extends to the circulation field 20H, preferably over the entire width of the circulation field 20H, measured along the Y direction. Along the X direction, the receiving surface 41 H extends to the injection rim 25H, preferably over the entire length L25H of the rim 25H. Opposite the Y direction, the receiving surface 41 H advantageously extends to the back 27H, if the back 27H is provided, preferably over the entire length of the back 27H. The receiving surface 41 H is entirely arranged within the main closed loop 31 H.

[0090] The receiving surface 41 H extends along, i.e. is coplanar with, the surface plane P11 H. The receiving surface 41 H is preferably entirely planar along the surface plane P11 H. The receiving surface 41 H is thus advantageously coplanar with the bottom of the channels of the circulation field 20H. The receiving surface 41 H is thus advantageously coplanar with the injection rim 25H, preferably at least for the parts of the injection rim 25H which connect the routing field 21 H to the orifices 29H. The receiving surface 41 H is thus advantageously coplanar with the peripheral zone 23H, preferably at least with the parts of the peripheral zone 23H on which the seal 24H is applied.This coplanar arrangement of the receiving surface 41 H advantageously facilitates the formation of the guide 50H directly on the face 11 H, in particular by overmolding, in particular simultaneously with the overmolding of the seal 24H if the seal 24H is also overmolded.

[0091] Along the plane P11 H, the surface 41 H preferentially surrounds the cavity 42H. The anchoring cavity 42H is formed as a hollow from the surface 41 H, in the opposite direction to the Z direction. In other words, the cavity 42H is hollow beyond the plane P11 H. Preferably, the cavity 42H comprises a bottom 45H, which is preferentially flat, parallel to the plane P11 H. The plane P11C is preferentially arranged between the bottom 45H and the plane P11 H, along the Z direction, as visible in FIG. 6.

[0092] Along the plane P11 H, in particular along the direction X, the anchoring cavity 42H is advantageously arranged between the circulation field 20H and the injection rim 25H, in particular between the circulation field 20H and the row of orifices 29H. Preferably, respective free ends of the spacer pads 36H are arranged between the row of orifices 29H and the anchoring cavity 42H, and preferably between the row of orifices 29H and the receiving surface 41 H.

[0093] The anchoring cavity 42H advantageously has, on the injection rim side 25H, an edge 43H, and, on the circulation field side 20H, an edge 44H. The edges 43H and 44H delimit the cavity 42H, each connecting the bottom 45H to the surface 41C, in the direction Z. The edges 43H and 44H delimit the cavity 42H between them, in the direction X. Preferably, the edges 43H and 44H are parallel to each other. Preferably, the edge 43H extends parallel to the injection rim 25H, in particular parallel to the orifices 29H. The edge 43H advantageously runs along the injection rim 25H, here over the entire length L25H. Alternatively, it is provided that the edge 43H runs along the rim 25H extending over at least 50% of the length L25H, preferably over at least 80% of the length L25H.This allows in particular to connect together in a single piece the 52H walls over more than half of the length L25H which ensures good positioning of said 52H walls while guaranteeing good fluid flow, from the orifices 29H to the flow field 20H. In addition, this also makes it easier to install the 50H guide.

[0094] Preferably, it is provided that the location 40H is formed by stamping the plate 10, advantageously at the same time as the stamping forms other parts of the plate 10, such as the field 20H. In particular in the case of stamping, so that the plate 10 forms the cavity 42H, formed in a hollow by the face 11H, the plate 10 also preferentially forms, in a corresponding manner, an anchoring cavity back 27C, formed in relief by the face 11C, in the opposite direction to the Z direction. The back 27C is visible in Figure 6, but also in Figures 3 and 4. The back 27C takes the same shape as the cavity 42H, in negative, that is to say in relief rather than in hollow. The anchoring cavity back 27C projects, in the opposite direction to the Z direction, relative to the surface plane P11C.

[0095] The guide 50H is complementary to the receiving location 40H and is configured to be received at the receiving location 40H as shown in Figures 5 and 6. Similarly, the receiving location 40H is complementary to the guide 50H and is configured to receive the guide 50H. The polar plate 10 and the guide 50H therefore have a connection between them and aim at a common inventive concept of forming the routing field 21H.

[0096] The 50H guide is formed in one piece, i.e. monolithically. The 50H guide is formed from a seal material, for example an elastomer, preferably the same seal material as that of the 24H peripheral seal. The 50H guide comprises a 51H anchor mat and 52H walls, which form a single monolithic piece, i.e. the 51H mat is made of a single material with the 52H walls.

[0097] As shown in Figures 5 and 6, the belt 51 H is housed in the anchoring cavity 42H, preferably so as to completely fill the anchoring cavity. Thanks to the belt 51 H, the guide 50H is firmly anchored to the receiving location 40H of the plate 10, at least along the plane P11 H.

[0098] The anchoring mat 51 H preferably has a shape complementary to that of the cavity 42H. For example, the mat has a strip shape that extends transversely relative to the walls 52H. By “transversely”, it is meant that the mat is arranged across the walls, that is to say that it intersects the walls. For example, the direction of extension of the mat intersects the direction of extension of each of the walls with a non-zero angle, preferably with an angle A52, shown in Figure 6, between 20 and 90°. The angle A52 is measured in the opposite direction to the Y direction. In particular, the anchoring mat 51 H has a bottom wall 56H which matches the shape of the bottom 45H. Preferably, the bottom wall 56H is parallel to the plane P11 H. The plane P11C is preferably interposed between the bottom wall 56H of the belt 51 H and the plane P11 H.In particular, the anchoring mat 51 H has edge walls 54H and 55H, which respectively match the edges 43H and 44H of the cavity 42H. The edge walls 54H and 55H extend transversely relative to the walls 52H. In particular, these edge walls 54H and 55H are advantageously parallel to each other and delimit the mat 51 H in the direction X. In particular, these edge walls 54H and 55H extend in the direction Z from the bottom wall 56H, at least up to the surface plane P11 H.

[0099] The anchoring mat 51 H preferably comprises a surface wall 53H, which is preferably planar and advantageously coplanar with the plane P11 H, as shown in FIG. 6, that is to say, is coplanar with the receiving surface 41 H. The surface wall 53H is opposite the bottom wall 56H of the mat 51 H in the Z direction, and is connected to the bottom wall 56H by the edge walls of the mat 51 H. Consequently, the anchoring mat 51 H advantageously fills the cavity 42H so that the mat 51 H extends the receiving surface 41 H at the location of the cavity 42H. In this case, the mat 51 H is advantageously entirely received in the anchoring cavity 42H so as not to protrude from the surface plane P11 H. This advantageously makes it possible not to disturb the flow of the functional fluid and not to reduce the passage section of the latter.

[0100] Alternatively, it could be provided that all or part of the belt 51 H extends beyond the plane P11 H in the Z direction, that is to say protrudes from the cavity 42H. Preferably, the belt 51 H is thicker, in the Z direction, than the sheet or the foil constituting the plate 10, the thickness of the belt being measured parallel to the Z direction, from the bottom wall 56H to the surface wall 53H.

[0101] The 52H walls are arranged side by side and at a distance from each other along the surface plane P11 H, in particular being distributed along the Y direction. Each 52H wall connects the injection edge 25H to the circulation field 20H, extending along the receiving surface 41 H and the belt 51 H. The 52H walls are attached to the belt 51 H, so as to be connected to each other by said belt 51 H. The belt 51 H advantageously connects all the 52H walls to each other. Preferably the belt 51 H connects at least three 52H walls to each other, preferably at least five 52H walls.

[0102] Each wall 52H comprises an application surface 63H and a top surface 64H. Each wall 52H bears against the receiving surface 41H, in the opposite direction to the Z direction, via the application surface 63H, preferably over the entire application surface 63H. Consequently, the application surface 63H is coplanar with the plane P11H, over the entire area of ​​the application surface 63H. Consequently, the carpet 51H projects from the walls in the opposite direction to the Z direction, to extend beyond the plane P11H and even beyond the plane P11C.

[0103] Along the Z direction, each wall 52H bears against the face 91, in particular against the peripheral zone 97, preferably over the entire surface 64H. Preferably, the walls 52H are not in contact with the exchange zone 93.

[0104] Perpendicular to the plane P11 H, namely along the Z direction, each 52H wall projects from the plane P11 H.

[0105] Each wall 52H comprises a main portion 60H, a primary end 61H and a secondary end 62H. The main portion 60H connects the primary end 61H to the secondary end 62H, preferably without interruption, and preferably such that the wall is unbranched from the end 61H to the end 62H. The apex surface 64H preferably extends from the end 61H to the end 62H, and over the entire main portion 60H. The application surface 63H extends from the secondary end 62H, over a portion of the main portion 60H, to the edge wall 55H of the belt 51H. In other words, each secondary end 62H is designed to bear on the receiving surface 41H via the portion of the application surface 63H when the guide is received on the receiving location 40H.In other words, each secondary end 62H is arranged, in projection in the surface plane P11 H, beyond the anchoring mat 51 H, and comprises a portion of the application surface 63H. Thus, each end 62H is designed to bear on the receiving surface 41 H via its own portion of the application surface 63H, when the guide 50H is received on the receiving location 40H.

[0106] The other part of the main part 60H and the primary end 61H do not have an application surface 63H and extend, in the Z direction, from the belt 51H. In other words, each primary end 61H is arranged, in projection in the surface plane P11H, in the anchoring belt 51H so as not to come to bear on the receiving surface 41H when the guide 50H is received on the receiving location 40H. More precisely, each primary end 61H ends at the edge wall 54H. Alternatively, it could be provided that each primary end 61H is set back from the edge wall 54H in the plane P11H, and is therefore positioned between the two edge walls 54H and 55H.

[0107] As shown in Figure 5, the primary ends 61H are preferably arranged in a row which is parallel to the injection rim 25H. This makes it possible to distribute the flow of the functional fluid homogeneously while optimizing the space available in the routing field 21H. Preferably, the secondary ends 62H are arranged in a row which runs along the circulation field 20H, that is to say here in a row parallel to the direction Y.

[0108] Preferably, from end 61 H to end 62 H, wall 52 H has a constant height, measured perpendicular to plane P11 H, from plane P11 H to surface 64 H.

[0109] Preferably, since the 36H bracing blocks are already provided, it is not mandatory for the 52H walls to themselves form 36H bracing blocks.

[0110] Therefore, it is advantageously provided that for each wall 52H, the primary end 61H, the main part 60H and the secondary end 62H are of equal width, the width being measured parallel to the plane P11H transversely to the wall 52H. This makes it possible to limit the fluid disturbances induced by a possible change in width of the channels 57H.

[0111] Preferably, the secondary ends 62H are further apart from each other in the Y direction than are the primary ends 61 H, so that the walls 52H are arranged in a fan shape in the plane P11 H. This makes it possible to distribute the gas flow from the orifices 29H evenly over the entire width of the circulation field 20H.

[0112] Preferably, each wall 52H projects from the belt 51 H, in the direction Z, in particular at the end 61 H. In particular, each wall 52H projects from the surface wall 53H, in the direction Z. The walls 52H being arranged side by side, they delimit channels 57H, each channel being delimited by two of the walls 52H, between being arranged between said two walls 52H in the direction Y. The channels 57H are arranged side by side along the surface plane P11 H, being separated two by two by one of the walls 52H. Each channel 57H includes a respective primary inlet 58H, bordered by two of the primary ends 61H. Here the primary inlets 58H are also delimited by the surface wall 53H of the belt 51H. Each primary inlet 58H opens onto the injection rim 25H. Each channel 57H includes a respective secondary inlet 59H, bordered by two of the secondary ends 62H.Here the secondary inlets 59H are also delimited by the reception surface 41H. Each secondary inlet 59H opens onto the circulation field 20H. From the primary inlet 58H to the secondary inlet 59H, the channel 57H is preferably not branched.

[0113] When the guide 50H is received at the receiving location 40H, the channels 57H are also delimited, along the Z direction, by, on the one hand, the surface 41H and the belt 51H, and, on the other hand, by the face 91.

[0114] The walls 52H have the function of guiding the primary reactive fluid, through the channels 57H, from the injection rim 25H to the circulation field 20H. In particular, the primary reactive fluid coming from the injection rim 25H is admitted into the inlet 58H of the channel 57H. In particular, the main part 60H of the walls 52H guides the fluid from the primary inlet 58H to the secondary inlet 59H. In particular, the primary reactive fluid escapes from the channel 57H via the inlet 59H to be admitted into the circulation field 20H. The primary reactive fluid, thus guided by the guide 50H, circulates from the distribution orifice 15H to the circulation field 20H, circulating on the surface of the face 11H, after having passed through the injection orifices 29H, via the injection rim 25H, then via the receiving location 40H combined with the guide 50H.

[0115] The guide 50H and the location 40H therefore duly form the routing field 21H, which, on the surface of the face 11H, fluidically connects the injection rim 25H to the circulation field 20H, guiding the primary reactive fluid along the face 11H through the channels 57H.

[0116] Preferably, as shown in Figure 5, the guide 50H belongs to the peripheral seal 24H, in that the guide 50H is attached to another part of the seal 24H, preferably to the main closed loop 31 H, by means of a tab 69H, visible in Figure 5. The tab 69H also belongs to the seal 24H. The tab 69H is formed from the same seal material as the rest of the seal 24H, including the guide 50H. Then the seal 24H, including in particular the main loop 31 H and the guide 50H, are monolithic and formed in one piece. It is thus particularly advantageous to form both the guide 50H and the main loop 31 H in a single overmolding in situ, in the same overmolding, directly on the plate 10.Alternatively, if the 24H seal is a part initially separate from the plate 10 and which is then added, the 50H guide is already attached to the main loop 31 H, which facilitates the relative positioning of these parts at the time when the seal is affixed to the plate 10.

[0117] Alternatively, the 50H guide and the 24H seal are separate parts, and the 69H tab is not provided. This can be advantageous to make the manufacture of the 24H seal independent of that of the 50H guide.

[0118] Forming the routing field 21 H as described above minimizes the consequences on the face 11 C opposite the face 11 H when the functional elements of the plate are obtained by stamping, since the cavity 42 H, causing the presence of the back 27 C, occupies a particularly modest area on the face 11 C, and which can be freely arranged. The receiving surface 41 H, for its part, causes the presence of a flat surface on the face 11 H, which can also serve as the receiving surface 41 C, as explained below. The back 27H, which is the consequence of an anchoring cavity 42C formed in a hollow on the face 11C as explained below, is arranged, on the face 11 H, in an area which is not a hindrance to the useful elements of the face 11 H, namely between the receiving location 40H, the distribution orifices 15C and 150 and the circulation field 20H.In fact, the functional fluid is not disturbed by the presence of this 27H back since it is located in an area not reached by said functional fluid.

[0119] The description of the conveying field 21 H above applies preferentially to that of the conveying field 22H and is therefore not detailed. The conveying field 22H is preferentially identical to the field 21 H, due to the central symmetry of the separator 5 with respect to an axis parallel to the Z direction. During use, the walls and channels of the conveying field 22H operate in the opposite direction to those of the conveying field 21 H, since the primary reactive fluid, as well as the reaction products formed in the circulation field 20H, flow from the circulation field 20H to the distribution orifice 16H, being guided successively via the conveying field 22H, via the rim 26H, through the injection orifices, to the orifice 16H.

[0120] As shown very schematically in Figure 2, the face 1110 of the separator 105 has a structure and a structure and an operation similar to that of the face 11 H of the separator 5, except that the face 1110 guides the secondary reactive fluid and not the primary reactive fluid. The face 1110 and the face 92 are in abutment against each other in the Z direction while being superimposed. On the face 1110, the polar separator 105 comprises a circulation field 1200, which is superimposed with the exchange zone 93, two routing fields 1210 and 1220, superimposed with the peripheral zone 97, a peripheral seal 1240 and two injection rims 1250 and 1260, respectively delimiting the orifices 1150 and 1160. The orifice 1150 supplies the face 1110 with the secondary reactive fluid via the rim 1250.The secondary reactive fluid is guided from the rim 1250 to the circulation field 1200 via the routing field 1210, where it participates in the electrochemical reaction by being in contact with the exchange zone 93. The secondary reactive fluid and the reaction products are then guided from the circulation field 1200 to the rim 1260 via the routing field 1220. The secondary fluid and the reaction products are finally discharged through the orifice 1160, from the rim 1260. The seal 1240 is interposed between the face 1110 and the face 92 in the Z direction, forming a main closed loop surrounding at least the circulation field 1200 and the routing fields 1210 and 1220, which makes it possible to prevent the secondary reactive fluid from escaping at the periphery. The 1240 seal also includes secondary closed loops to prevent fluid from escaping from distribution ports that are not already surrounded by the primary closed loop.

[0121] The polar plate 10 is described here in more detail concerning the plate face 110, in connection with figures 2, 3 and 4.

[0122] The plate face 110 comes opposite the face 111 C of the separator 105 of another cell 4 of the stack 2, being superimposed parallel to the direction Z.

[0123] On the side of the plate face 110, the polar plate 10 mainly comprises a circulation field 200, two routing fields, including a routing field 210 shown in FIGS. 3 and 4, a peripheral seal 240 and two injection rims, including an injection rim 250 shown in FIGS. 3 and 4. The aforementioned anchoring cavity back 270 is also found.

[0124] A peripheral zone 230, superimposed on the peripheral zone 23H, is formed directly by the face 110. The peripheral zone 230 frames the circulation field 200, the routing fields and the injection edges of the face 110.

[0125] The circulation field 200 is preferably arranged in the center of the face 110, being superimposed on the field 20H. Along the X direction, the circulation field 200 is arranged between the routing fields of the face 110, arranged at opposite ends of the circulation field 200.

[0126] Along the X direction, the routing field 210 is arranged between the orifices 15H, 150 and 150 and the circulation field 200. In particular, the circulation field 200 starts at one end of the routing field 210. At an opposite end of the routing field 210, the injection rim 250, belonging to the peripheral zone 23C, connects the orifice 15C to the routing field 21C. The cavity back 27C is arranged so as to be adjacent to the routing field 21C and the orifice 15H.

[0127] Along the X direction, the other routing field is arranged between the circulation field 20C and the ports 16H, 16C and 160, which are adjacent to this other routing field. In particular, the circulation field 20C ends at one end of this other routing field. At an opposite end of this other routing field, the second injection rim connects this other routing field to the port 16C.

[0128] The polar separator 5 is configured so that the cooling fluid circulating in the orifice 15C is admitted between the face 11C and the face 111C via the injection rim 25C, then is discharged through the orifice 16C via the other injection rim. In doing so, the cooling fluid circulates along the face 11C, successively along the injection rim 25C, the routing field 21C, the circulation field 20C, the other routing field and the other injection rim.

[0129] The peripheral seal 24C is received on the plate face 11C, in particular is entirely received on the peripheral zone 23C. Preferably, over the entire portion of the peripheral zone 23C receiving the seal 24C, said seal 24C extends along the face plane P11C. Along the direction Z, the seal 24C comes into contact with the face 111C of the separator 105. The seal 24C thus delimits zones sealed against functional fluids, between the faces 11C and 111C, preventing said functional fluids from escaping peripherally.

[0130] The peripheral seal 24C is preferably formed in one piece. The peripheral seal 24C is made of a seal material, i.e. for example an elastomer, preferably the same seal material as the seal 24H. The peripheral seal 24C is preferably obtained by overmolding said seal 24C on the face 11C, or on the face 11C. Alternatively, the seal 24C can be manufactured separately, then added to the face 11C, or to the face 111C.

[0131] The peripheral seal 24C comprises a main closed loop 31C, formed on the face 11C, or at least interposed between the face 11C and the face 111C. The main closed loop 31C has the function of maintaining the cooling fluid inside the main loop 31C, between the faces 11C and 111C. On the side of the face 11C, the main closed loop 31C surrounds at least the circulation field 20C and the routing fields.

[0132] Advantageously, the main closed loop 31 C further surrounds the injection rims and the orifices 15C and 16C. In Figure 3, this is shown for the rim 25C and the orifice 15C. The coolant can flow from the orifice 15C to the injection rim 25C along the face 11 C, without passing through the plate 10 and without passing along the face 11 H. Similarly, the coolant can flow from the other injection rim to the orifice 16C along the face 11 C without passing through the plate 10. This allows the injection rims of the face 11C to be free of injection orifices, as shown in Figure 3 for the rim 25C.

[0133] Advantageously, only the orifices 15H, 150, 16H and 160 are arranged outside the main closed loop 31 C, as shown in FIG. 3 for the orifices 15H and 150. Similarly, the orifices 115H, 1150, 116H and 1160 are arranged outside the main closed loop 31 C. As shown for the injection orifices 29H in FIG. 3, the injection orifices of the injection rims 25C and 26H are also arranged outside the main loop 31 C. Consequently, all the cooling fluid circulating on the surface of the face 11C is surrounded by the main loop 31 C, preventing said fluid from escaping at the periphery of the face 11 C.

[0134] Preferably, when the injection rim of the opposite face 11 H comprises injection orifices, the peripheral seal 24C also comprises spacer pads received on the face 11 C, on the back of the injection rim carrying the injection orifices and outside the main loop 31 C. Each spacer pad bears against the face 111 C in the direction Z, so as to be interposed between the faces 11 C and 111 C. Each injection pad advantageously extends from the main closed loop 31 C, in the direction of the distribution orifice served by the injection orifices, being arranged between two successive injection orifices. Each injection pad is preferably formed in one piece with the main loop 31C. For example, as shown in FIG. 3, spacer pads 36C are provided, which extend from the main loop 31C, towards the orifice 15H.At the location of the spacer pads, the injection edge preferably extends along the surface plane P11C.

[0135] Preferably, the peripheral seal 24C comprises secondary closed loops, each surrounding one of the distribution orifices and being received on the plate face 11C. Each secondary closed loop also comes into contact with the face 111C. Preferably, each secondary closed loop is formed integrally with the main loop 31C. Preferably, each orifice 15H, 150, 16H and 160, which is not already surrounded by the main loop 31C, is surrounded by a respective secondary closed loop belonging to the seal 24C. Each secondary loop also being in contact with the face 111C, each orifice 115H, 1150, 116H and 1160 is also surrounded by one of the respective secondary loops, to form the corresponding gallery. Each secondary loop thus ensures that the functional fluid circulating in the gallery concerned does not escape outside cell 4, nor towards the interior of the main loop 31 C.As shown in Figure 3, in particular, a secondary closed loop 33C surrounds the port 15H and a secondary closed loop 35C surrounds the port 150. As shown in Figure 3, the secondary closed loops 33C and 35C and the main loop 31C advantageously have common parts. The same considerations apply to the secondary loops surrounding the ports 16H and 160 respectively.

[0136] Preferably, no portion of the seal 24C subdivides the one or more closed loops into multiple closed loops formed by the seal 24C.

[0137] Preferably, the circulation field 20C is formed directly by the plate face 11C, as a negative of the circulation field 20H, due to the obtaining of these elements by stamping. Preferably, the circulation field 200 has a generally rectangular shape in the X and Y directions. The circulation field 200 comprises channels, which are hollow in the opposite direction of the Z direction relative to the face plane P11C, and which correspond to the walls of the field 20H. Preferably, each channel connects the two ends of the circulation field 200 together in the X direction, that is to say extends from the routing field 210 to the other routing field. The channels are arranged side by side, being delimited from each other by walls, each wall of the field 200 corresponding to one of the channels of the field 20H. Preferably, a vertex face of the channels of the field 200 is coplanar with the plane P11C.

[0138] The cooling fluid circulating along the face 110 is admitted along the circulation field 200 from the routing field 210, and circulates to the opposite end of the circulation field 200 via the channels of said circulation field 200, being guided by said channels and being distributed over said channels. At the opposite end of the circulation field 200, the cooling fluid is admitted into the other routing field. During its circulation along the field 200, the cooling fluid is charged with heat from the exothermic electrochemical reactions taking place in the cell 4, to cool the cell 4.

[0139] As shown in Figures 3 and 4, the routing field 21C is formed in part by a receiving location 40C formed by the plate face 11C, i.e. formed directly by the plate 10. Another part of the routing field 21C is formed by a guide 50C, which is a part distinct from the plate 10, added or applied to the plate face 11C, in particular, received on the receiving location 40C. Optionally, yet another part of the routing field 21C is formed by an auxiliary guide 70C, which is a part distinct from the plate 10 and the guide 50C, added or applied to the plate face 11C, in particular, received on the receiving location 40C. Preferably, the receiving location 40C is formed entirely by the face 11C.The receiving location 40C connects the injection rim 25C, over an entire length L25C of the injection rim 25C, to the circulation field 20C, over the entire width of the circulation field 20C in the direction Y. In other words, the location 40C occupies the entire area of ​​the routing field 21 C. The length L25C is measured along the plane P11C. As shown in FIG. 3, the length L25C is preferably measured along the contour of the orifice 15C, from a first part of the main closed loop 31 C to another part of the main closed loop 31 C, connected by the injection rim 25C.

[0140] The receiving location 40C includes the aforementioned receiving surface 41C and anchoring cavity 42C, best seen in Figure 4. The receiving surface 41C and anchoring cavity 42C are formed directly by the face 11C.

[0141] In the opposite direction to the X direction, the receiving surface 41 C extends to the circulation field 20C, preferably over the entire width of the circulation field 20C, measured in the Y direction. In the X direction, the receiving surface 41 C extends to the injection rim 25C, preferably over the entire length L25C of the rim 25C. In the Y direction, the receiving surface 41 C advantageously extends to the back 27C, preferably over the entire length of the back 27C, which is arranged between the surface 41 C and the orifice 15H. In the opposite direction to the Y direction, the receiving surface 41 C advantageously extends to the main loop 31 C, bordering the orifice 150. The receiving surface 41 C is entirely arranged inside the main closed loop 31 C.

[0142] The receiving surface 41C extends along, i.e. is coplanar with, the surface plane P11C. The receiving surface 41C is preferably entirely planar along the surface plane P11C. The receiving surface 41C is thus advantageously coplanar with the top of the walls of the circulation field 20C. The receiving surface 41C is thus advantageously coplanar with the injection rim 25C, which is itself coplanar with the plane P11C. The receiving surface 41C is thus advantageously coplanar with the peripheral zone 23C, preferably at least with the parts of the peripheral zone 23C on which the seal 24C is applied. This coplanar arrangement advantageously facilitates the formation of the guide 50C directly on the face 11C, in particular by overmolding, in particular simultaneously with the overmolding of the seal 24C if the seal 24C is also overmolded.

[0143] Along the plane P11C, the surface 41C preferably surrounds the cavity 42C. The anchoring cavity 42C is formed as a hollow from the surface 41C, along the Z direction. In other words, the cavity 42C is hollow beyond the plane P11C. Preferably, the cavity 42C comprises a bottom 45C, which is preferably flat, parallel to the plane P11C. The plane P11H is preferably arranged between the bottom 45C and the plane P11C, along the Z direction, as visible in FIG. 3.

[0144] Along the plane P11 C, in particular along the direction X, the anchoring cavity 42C is advantageously arranged between the circulation field 20C and the injection rim 25C.

[0145] The anchoring cavity 42C advantageously has, on the injection rim 25C side, an edge 43C, and, on the circulation field 20C side, an edge 44C. The edges 43C and 44C delimit the cavity 42C, each connecting the bottom 45C to the surface 41C, in the direction Z. The edges 43C and 44C delimit the cavity 42C between them, in the direction X. Preferably, the edges 43C and 44C are oblique to each other. Preferably, the edge 43C extends parallel to the injection rim 25C. The edge 43C advantageously runs along the injection rim 25C, here over the entire length L25C.

[0146] Alternatively, it is provided that the edge 43C runs along the edge 25C, extending over at least 50% of the length L25C, preferably over at least 80% of the length L25C, but not more than 90% of the length L25C. This makes it possible in particular to connect the walls 52C together in a single piece over more than half of the length L25C, which ensures good holding in position of said walls 52C while guaranteeing good fluid flow, from the orifices 29C to the flow field 20C. In addition, this also makes it easier to position the guide 50C.

[0147] It can be provided that the edge 43C extends over a length between 50 and 90% of the length L25C, so that a part of the length L25 is not served by the guide 50C. Preferably, the edge 44C connects a lateral end of the circulation field 20C to the edge 43C, so that an area of ​​the face 11C connecting the orifice 15H to the circulation field 20C, over the entire width of the circulation field 20C in the direction Y, is not occupied by the cavity 42C, but is occupied by the receiving surface 41C. This allows the cavity back 27H, on the opposite face 11H, to leave sufficient space for the routing field 21H connecting the orifice 15H to the circulation field 20H. Similarly, the cavity back 27C leaves sufficient room for the formation of the routing field 21C.

[0148] The 27H back takes the same shape as the 42C cavity, in negative, that is to say in relief rather than in hollow.

[0149] The guide 50C is complementary to the receiving location 40C and is configured to be received on the receiving location 40C as shown in Figures 3 and 4. Similarly, the receiving location 40C is complementary to the guide 50C and is designed to receive the guide 50C. However, the guide 50C does not occupy the entire area of ​​the location 40C, but shares it with the auxiliary guide 70C. The guide 50C is formed in one piece, i.e. monolithically. The guide 50C is formed of a seal material, for example an elastomer, preferably the same seal material as that of the peripheral seal 24C.

[0150] The 50C guide includes a 51C anchor mat and 52C walls, which form a single monolithic piece, i.e. the 51C mat is made of the same material as the 52C walls.

[0151] As shown in Figures 3 and 4, the belt 51C is housed in the anchoring cavity 42C, preferably so as to completely fill the anchoring cavity 42C. Thanks to the belt 51C, the guide 50C is firmly anchored to the receiving location 40C of the plate 10, at least along the plane P11C.

[0152] The anchoring mat 51 C preferably has a shape complementary to that of the cavity 42C. For example, the mat 51 C has a plate shape, quadrilateral or triangular, which extends transversely relative to the walls 52C. In particular, the anchoring mat 51 C has a bottom wall 56C which matches the shape of the bottom 45C. Preferably, the bottom wall 56C is parallel to the plane P11 C. The plane P11 H is preferably interposed between the bottom wall 56C of the mat 51 C and the plane P11C. In particular, the anchoring mat 51 C has edge walls 54C and 55C, which respectively match the edges 43C and 44C of the cavity 42C. The edge wall 54C extends transversely relative to the low walls 52C, and the wall 55C extends obliquely relative to the low walls 52C and the edge 54C. In particular, these edge walls 54C and 55C delimit the carpet 51C in the direction X.In particular, these edge walls 54C and 55C extend in the Z direction from the bottom wall 56C, at least up to the surface plane P11C.

[0153] The anchoring mat 51 C preferably comprises a surface wall 53C, which is preferably planar and advantageously coplanar with the plane P11 C, as shown in FIG. 4, that is to say, is coplanar with the receiving surface 41 C. The surface wall 53C is opposite the bottom wall 56C in the Z direction, and is connected to the bottom wall 56C by the edge walls 54C and 55C. Consequently, the anchoring mat 51 C advantageously fills the cavity 42C so that the mat 51 C extends the receiving surface 41 C at the location of the cavity 42C. In this case, the mat 51 C is advantageously entirely received in the anchoring cavity 42C so as not to protrude from the surface plane P110.

[0154] Alternatively, it could be provided that all or part of the belt 51 C extends beyond the plane P110 in the opposite direction to the Z direction, that is to say protrudes from the cavity 420. Preferably, the belt 51 C is thicker, in the Z direction, than the sheet or the foil constituting the plate 10, the thickness of the belt being measured parallel to the Z direction, from the bottom wall 56C to the surface wall 53C.

[0155] The walls 52C are arranged side by side and at a distance from each other along the surface plane P11C, in particular being distributed along the Y direction. Each wall 52C connects the injection edge 25C to the circulation field 20C, extending along the belt 51C and the receiving surface 41C. The walls 52C are attached to the belt 51C, so as to be connected to each other by said belt 51C. The belt 51C advantageously connects all the walls 52C to each other. Preferably the belt 51C connects at least three walls 52C to each other, preferably at least five walls 52C.

[0156] Each wall 52C comprises an application surface 63C and a top surface 64C. Each wall 52C bears against the receiving surface 41C, in the Z direction, via the application surface 63C, preferably over the entire application surface 63C. Consequently, the application surface 63C is coplanar with the plane P11C, over the entire area of ​​the application surface 63C. Consequently, the mat 51C projects from the walls 52C in the Z direction, to extend beyond the plane P11C and even beyond the plane P11H.

[0157] In the opposite direction to the Z direction, each wall 52C bears against the face 111 C, in particular against the peripheral zone 97, preferably over the entire surface 64C.

[0158] Perpendicular to the plane P11 C, namely in the opposite direction to the Z direction, each wall 52C projects from the plane P11 C.

[0159] Each wall 52C comprises a main portion 60C, a primary end 61C and a secondary end 62C. The main portion 60C connects the primary end 61C to the secondary end 62C, preferably without interruption, and preferably such that the wall is unbranched from the end 61C to the end 62C. The apex surface 64C preferably extends from the end 61C to the end 62C, and over the entire main portion 60C. The application surface 63C extends from the secondary end 62C, over a portion of the main portion 60C, to the edge wall 55C of the mat 51C, where it is interrupted. The application surface 63C extends from the primary end 61C to the edge wall 54C of the belt 51C, where it is interrupted.In other words, each end 61C and 62C is designed to bear on the receiving surface 41C via application surface portions 63C when the guide 50C is received on the receiving location 40C. A portion of the main portion 60C does not include an application surface 63C and extends, in the opposite direction to the Z direction, from the belt 51C. In other words, each primary end 61C and secondary end 62C is arranged, in projection in the surface plane P11C, beyond the anchoring belt 51C, on either side of the anchoring belt 51C, and comprises a respective portion of the application surface 63C. Thus, each end 61C and 62C is designed to bear on the receiving surface 41C via its own portion of the application surface 63C, when the guide 50C is received on the receiving location 40C.

[0160] As shown in Figure 3, the primary ends 61C are preferably arranged in a row which is parallel to the injection rim 25C. Preferably, the secondary ends 62C are arranged in a row which runs along the circulation field 20C, that is to say here in a row parallel to the direction Y.

[0161] Preferably, from the end 61C to the end 62C, the wall 52C has a constant height, measured perpendicular to the plane P11C, from the plane P11C to the surface 64C.

[0162] Preferably, spacer pads are here integrated into the walls 52C by being formed by the ends 61C. For this, for each wall 52C, the end 61C is widened relative to the main part 60C, the width being measured parallel to the plane P11C and transversely to the wall 52C. Furthermore, it is advantageously provided that for each wall 52C, the secondary end 62C and the main part 60C are of equal width.

[0163] Preferably, the secondary ends 62C are further apart from each other in the Y direction than the primary ends 61C, so that the walls 52C are arranged in a fan shape along the plane P11C. This makes it possible to distribute the gas flow coming from the distribution orifice 15C evenly over the entire width of the circulation field 20C.

[0164] Preferably, each wall 52C projects from the belt 51C, in the opposite direction to the Z direction, in particular at the end 61C. In particular, each wall 52C projects from the surface wall 53C, in the opposite direction to the Z direction.

[0165] The walls 52C being arranged side by side, they delimit channels 57C, each channel 57C being delimited by two of the walls 52C, between being arranged between said two walls 52C in the direction Y. The channels 57C are arranged side by side in the surface plane P11C, being separated two by two by one of the walls 52C. Each channel 57C comprises a respective primary inlet 58C, bordered by two of the primary ends 61C. Here the primary inlets 58C are also delimited by the receiving surface 41C. Each primary inlet 58C opens onto the injection rim 25C. Each channel 57C comprises a respective secondary inlet 59C, bordered by two of the secondary ends 62C. Here the secondary inlets 59C are also delimited by the receiving surface 41C. Each secondary inlet 59C opens onto the circulation field 20C. From the primary inlet 58C to the secondary inlet 59C, the channel 57C is preferably not branched.

[0166] The auxiliary guide 70C comprises walls 72C similar to the walls 52C and delimiting between them other channels. The auxiliary guide 70C is monolithic by being formed in the same joint material as above. In particular, the walls 72C comprise primary ends 81C aligned with the ends 61C and secondary ends 82C aligned with the ends 62C. Unlike the walls 52C, the walls 72C have an application surface which extends, for each wall 72C, from the end 81C to the end 82C, so that the walls 72C are fully received on the receiving surface 41C. Unlike the guide 50C, no part of the auxiliary guide 70C is received in the anchoring cavity 42C or another anchoring cavity. The guide 70C does not comprise an anchoring mat. The auxiliary guide 70C advantageously comprises a tab 71C which connects the walls 72C together. The auxiliary guide 70C rests on the receiving surface 41C.Thus, no part of the guide 70C extends beyond the plane P11C in the Z direction, unlike the belt 51 C of the guide 50C.

[0167] Along the Y direction, the guide 70C is arranged between the guide 50C and the orifice 15H. The ends 81C extend over a portion of the rim 25C which is not served by the ends 61C. Indeed, the cavity 42C and therefore the anchoring mat 51C extend over only a portion of the length L25C. The ends 82C serve a portion of the circulation field 20C which is not served by the ends 62C, for similar reasons.

[0168] When the guides 50C and the guide 70C are received at the receiving location 40C, the channels 57C are also delimited, in the direction Z, by, on the one hand, the surface 41C and the belt 51C, and, on the other hand, by the face 111C.

[0169] The walls 52C and 72C have the function of guiding the cooling fluid, through the channels, from the injection rim 25C to the circulation field 20C. The guides 50C and 70C, with the location 40C, therefore duly form the routing field 21C, which, on the surface of the face 11C, fluidically connects the injection rim 25C to the circulation field 20C, guiding the cooling fluid along the face 11C.

[0170] Preferably, as shown in Figure 3, the guide 50C does not belong to the peripheral seal 24C, in that the guide 50C is not attached to the seal 24C. On the other hand, it is advantageously provided that the auxiliary guide 70C belongs to the seal 24C by being attached to a part of the seal 24C, preferably to the main closed loop 31C, by means of a tab 69C, visible in Figure 3. The tab 69C also belongs to the seal 24C. The tab 69C is formed from the same seal material as the rest of the seal 24C. Then the seal 24C, including in particular the main loop 31C and the guide 70C, are monolithic and formed in one piece.

[0171] The description of the routing field 21 C above applies preferentially to that of the other routing field of the face 11C and is therefore not detailed. The routing fields are preferentially identical, due to the central symmetry of the separator 5 with respect to an axis parallel to the Z direction. During use, the walls and channels of the other routing field operate in the opposite direction to those of the routing field 21 C, since the cooling fluid flows from the circulation field 20C to the distribution orifice 16C, being guided successively via the routing field, via the injection rim, to the orifice 16C.

[0172] Any feature described above for one embodiment or variant is applicable to the other embodiments and variants described above, as far as technically possible.

Claims

CLAIMS 1.- Guide (50H; 50C), for a polar separator (5) of an electrochemical cell (4), the guide (50H; 50C) being configured to be received on a receiving location (40H; 40C) belonging to a plate face (11 H; 11C) of a polar plate (10) belonging to the polar separator (5), in order to form a routing field (21 H; 21C) on the plate face (11 H; 11C), capable of guiding a functional fluid along the plate face, the guide (50H; 50C) comprising: walls (52H; 52C), which are arranged side-by-side along a surface plane (P11 H; P11C), so as to delimit channels (57H; 57C) for guiding the functional fluid, the channels being arranged side-by-side along the plane surface, each channel being delimited between, and by, two of said walls, each wall comprising an application surface (63H;63C), which is coplanar with the surface plane and by means of which the wall is designed to bear on a receiving surface (41 H; 41 C) belonging to the receiving location (40H; 40C), when the guide (50H; 50C) is received on the receiving location; and an anchoring mat (51 H; 510), connecting the low walls together, such that the low walls and the anchoring mat together constitute a single monolithic piece of joint material, the anchoring mat extending from the low walls beyond the surface plane, so as to be able to be housed in an anchoring cavity (42H; 420) belonging to the receiving location, formed in a hollow from the receiving surface (41 H; 410), in order to anchor the guide (50H; 500) to the receiving location when the guide (50H; 500) is received on the receiving location.; 2.- Guide (50H; 500) according to claim 1, wherein each wall (52H; 520) comprises: a primary end (61 H; 610), each channel (57H; 570) comprising a primary inlet (58H; 580) bordered by two of the primary ends; a secondary end (62H; 620), each channel comprising a secondary inlet (59H; 590) bordered by two of the secondary ends; and a main portion (60H; 600), which connects the primary end to the secondary end (62H; 620), for guiding the functional fluid between the primary inlet and the secondary inlet of the channel delimited by said wall. 3.- Guide (500) according to claim 2, in which, for at least one of the walls (520), the primary end (610) forms a spacer pad, widened relative to the main part (600). Guide (50H) according to any one of claims 2 or 3, wherein, for at least one of the walls (52H), the primary end (61 H) and the main part (60H) are of equal width. Guide (50H; 50C) according to any one of claims 2 to 4 wherein, for at least one of the walls (52H; 52C), the secondary end (62H; 620) and the main part (60H;600) are of equal width. Guide (500) according to any one of claims 2 and 5, wherein, for at least one of the walls (520), the primary end (610) is arranged, along the surface plane (P11C), beyond the anchoring mat (510), and comprises a portion of the application surface (630), so that said primary end is designed to bear on the receiving surface (410) via the portion of the application surface when the guide is received on the receiving location (400). Guide (50H) according to any one of claims 2 to 5, in which, for at least one of the walls (52H), the primary end (61 H) is arranged, along the surface plane (P11 H), in the anchoring mat (51 H) so as not to come to bear on the receiving surface (410) when the guide is received on the receiving location (40H). Guide (50H; 500) according to any one of claims 2 to 7, in which the secondary ends (62H;620) are further apart from each other than the primary ends (61 H; 610). Polar plate (10), for a polar separator (5) of an electrochemical cell (4), the polar plate (10) comprising a plate face (11 H; 110), parallel to a surface plane (P11 H; P11C), and a first distribution orifice (15H; 150) passing through the polar plate (10) from the plate face, the plate face comprising: an injection rim (25H; 250), delimiting the first distribution orifice; a circulation field (20H; 200); and a receiving location (40H; 400), formed by the plate face and connecting the injection rim to the circulation field, such that a functional fluid can flow from the circulation field to the first distribution orifice or vice versa, by flowing on the surface of the plate face via the receiving location and the injection rim, the receiving location being configured to receive a guide (50H;500) belonging to the polar separator (5), in order to form, with said guide, a routing field (21 H; 210) arranged between the circulation field and the injection rim, to guide the functional fluid on the surface of the plate face of the circulation field to the injection rim or vice versa, the receiving location comprising:; • a receiving surface (41 H; 41 C), which is coplanar with the surface plane (P11 H; P11 C) and which is designed to receive low walls (52H; 52C) belonging to the guide, the receiving surface being configured so that each low wall bears against the receiving surface via a respective application surface (63H; 63C) belonging to said low wall, when the guide is received at the receiving location; and • an anchoring cavity (42H; 42C), which is formed in a hollow beyond the surface plane from the receiving surface and which is adapted to accommodate an anchoring mat (51 H; 51C) belonging to the guide and connecting the walls together, in order to anchor the guide to the receiving location when the guide is received on the receiving location. Polar plate (10) according to claim 9, in which the anchoring cavity (42H; 42C) has an edge (43H; 43C) which extends parallel to the injection rim (25H; 25C), along the injection rim over at least 50%, preferably over at least 80%, of a length (L25H; L25C) of the injection rim, the length of the injection rim being measured along the surface plane (P11 H; P11C). Polar plate (10) according to any one of claims 9 or 10, wherein: the polar plate (10) comprises a second distribution orifice (15C, 150; 15H) passing through the polar plate (10) from the plate face (11 H; 11C); and the plate face comprises an anchoring cavity back (27H; 27C) which projects from the surface plane (P11 H; P11C) and which is arranged between the receiving location (40H; 40C), the second distribution orifice, the circulation field (20H; 20C) and the first distribution orifice (15H; 15C).Polar separator (5), for an electrochemical cell (4), the polar separator comprising the guide (50H; 50C) according to any one of claims 1 to 8 and the polar plate (10) according to any one of claims 9 to 11 and the guide being received at the receiving location (40H; 40C), with the application surface (63H; 63C) of the walls (52H; 52C) bearing on the receiving surface (41H; 41C) and with the anchoring mat (51H; 51C) housed in the anchoring cavity (42H; 42C), so that the receiving location forms, with the guide, the routing field (21H; 21C), arranged between the circulation field (20H; 20C) and the injection rim (25H; 25C), for guiding the functional fluid to the surface of the face plate (11 H; 11 C), from the circulation field to the injection edge or vice versa.Polar separator (5) according to claim 12, wherein, perpendicular to the surface plane (P11 H; P11C), the anchoring mat (51 H; 51C) is entirely received in the anchoring cavity (42H; 42C) so as not to protrude from the surface plane. 14.- Polar separator (5) according to any one of claims 12 or 13, wherein: the polar separator further comprises a peripheral seal (24H; 24C), which is received on the plate face (11 H; 11C), forming a main closed loop (31 H; 31C) around the circulation field (20H; 20C) and the routing field (21 H; 21 C), in order to maintain the functional fluid circulating along the plate face inside the main closed loop; and the receiving location (40H; 40C) and the guide (50H; 50C) are arranged inside the main closed loop. 15.- Polar separator (5) according to claim 14, in which the guide (50H) belongs to the peripheral seal (24H), the guide is attached to the main closed loop (31 H) by means of a tab (69H) belonging to the peripheral seal, the peripheral seal constituting a single monolithic piece of seal material, including both the guide and the main closed loop. 16.- Polar separator (5) according to any one of claims 14 or 15, wherein: the injection rim (25H) comprises a row of injection orifices (29H), such that the functional fluid circulating on the surface of the plate face (11H) via the injection rim passes through the polar plate (10) via the injection orifices to reach the first distribution orifice (15H), or such that the functional fluid circulating in the first distribution orifice passes through the polar plate (10) via the injection orifices of the injection rim to reach the plate face, at the injection rim; the main closed loop (31H) comprises a rim portion (32H) received on the injection rim, between the first distribution orifice and the row of injection orifices; and the anchoring cavity (42H) is arranged between the row of injection ports and the circulation field (20H). 17.- Polar separator (5) according to any one of claims 14 or 15, in which the main closed loop (31 C) surrounds the distribution orifice (15C) and the injection rim (25C) so that the functional fluid can circulate from the injection rim to the first distribution orifice and vice versa along the plate face (11C), without passing through the polar plate (10). 18.- Fuel cell, comprising electrochemical cells (4), at least one of the electrochemical cells comprising: the polar separator (5) according to any one of claims 14 to 17, constituting a first polar separator; a second polar separator (105); and a membrane-electrode assembly (90), comprising an exchange zone (93) which includes a proton exchange membrane, the first polar separator, the membrane-electrode assembly and the second polar separator being superimposed in a stacking direction (Z), so that the membrane-electrode assembly is interposed between the first polar separator and the second polar separator, the peripheral seal (24H) of the first polar separator being interposed between the polar plate (10) of the first polar separator and the membrane-electrode assembly, the circulation field (20H) of the polar plate (10) of the first polar separator bearing against the exchange zone in the stacking direction (Z).

Images