Fuel cell stack and fuel cell comprising such a stack
Patent Information
- Application Number
- FR2023009350
- Authority / Receiving Office
- FR · FR
- Patent Type
- Utility models
- Current Assignee / Owner
- Filing Date
- 2023-09-06
- Publication Date
- 2025-03-07
- Estimated Expiration
- 2033-09-06
Smart Images
Figure 00000000_0000_ABST
Abstract
Description
Title of the invention: Stack of fuel cell cells and fuel cell comprising such a stack
[0001] The present invention relates to an assembly comprising a stack of fuel cell cells and a fuel cell comprising such an assembly.
[0002] The invention relates more particularly to an assembly comprising a stack of a plurality of proton exchange membrane fuel cell cells in which the cells each comprise an anode plate and a cathode plate sandwiching a Membrane Electrode Assembly (MEA).
[0003] Fuel cell cells (anode side and cathode side) generate heat (chemical reactions within the cell are exothermic) and must be cooled by a cooling circuit.
[0004] In the case of a cell composed of two plates sandwiching a Membrane Electrode Assembly, each plate (anodic or cathodic) comprises a side dedicated to the circulation of reactive gases (air or hydrogen opposite the Membrane Electrode Assembly) and a side (facing the outside of the cell) dedicated to the circulation of the cooling fluid (often a liquid).
[0005] Each cell in the stack must be cooled in the same way to ensure a uniform drop in performance over time. Indeed, an isolated cell, aging prematurely, can compromise the lifespan of the stack as a whole. Managing the two cells located at the ends of the stack can be tricky, because there is no heat input from one side of these cells. Thus, for an identical coolant inlet temperature, and given that the heat to be removed is less at these two cells located at the ends of the stack than at the other cells, this means that the cell is colder.
[0006] With state-of-the-art fuel cells, it is thus impossible to guarantee that all the cells have substantially the same difference between the temperature of the coolant entering the cell and the temperature of the coolant leaving the cell.
[0007] The present invention aims to effectively overcome these drawbacks by proposing an assembly comprising a stack of a plurality of proton exchange membrane fuel cell cells, the plurality of cells comprising a first cell at a first end of the stack and a last cell at a second end of the stack, each cell of the plurality comprising an anode plate and a cathode plate sandwiching an assembly Membrane Electrodes, each plate comprising a reactive face and a cooling face opposite each other, the reactive face of each plate being intended to face the Membrane Electrodes Assembly and being provided with reliefs and hollows forming a reactive circuit, for the circulation of a reactive fluid, the cooling face of the cathode plate of at least one of the cells being intended to face the cooling face of the anode plate of another of the cells, defining between them reliefs and hollows to form a first cooling circuit for the circulation of a cooling fluid, the first cooling circuit comprising a plurality of first cooling channels, one of the plates of the first cell forming with one of the plates of another of the cells, a second cooling circuit for the circulation of the cooling fluid,the second cooling circuit comprising a plurality of second cooling channels, the other of the plates of the first cell forming a first end plate, one of the plates of the last cell forming with one of the plates of another of the cells, a third cooling circuit for the circulation of the cooling fluid, the third cooling circuit comprising a plurality of third cooling channels, the other of the plates of the last cell forming a last end plate, the assembly comprising a closure plate comprising an electric current collection face intended to face a first electric current collector plate and a closure face fixed to the cooling face of the last end plate,the closure face and the cooling face of the last end plate defining between them reliefs and hollows to form a fourth cooling circuit for the circulation of the cooling fluid, the fourth cooling circuit comprising a plurality of fourth cooling channels, the assembly being configured so that the volume flow rate of the cooling fluid passing through the fourth cooling circuit is lower than the volume flow rate of cooling fluid passing through the first cooling circuit, for example lower by 30% to 55%, the volume flow rates being considered for the same speed of the cooling fluid.
[0008] Such an assembly makes it possible to ensure better thermal management of the stack, so that each cell has substantially the same difference between the temperature of the cooling fluid entering the cell and the temperature of the cooling fluid leaving the cell.
[0009] According to one embodiment, the closure face is glued or welded to the cooling face of the last end plate.
[0010] According to one embodiment, the assembly is configured so that the volume flow rate of the cooling fluid passing through the fourth cooling circuit is less than the volume flow rate of coolant passing through the second cooling circuit, for example 30% to 55% lower, the volume flow rates being considered for the same speed of the coolant and / or being configured so that the volume flow rate of the coolant passing through the fourth cooling circuit is lower than the volume flow rate of coolant passing through the third cooling circuit, for example 30% to 55% lower, the volume flow rates being considered for the same speed of the coolant.
[0011] According to one embodiment, each first cooling channel having a first average section, each fourth cooling channel having a fourth average section, the sections being considered in a plane orthogonal to the direction in which the cooling fluid circulates, the fourth average section being between 60% and 90% of the first average section.
[0012] According to one embodiment, each second cooling channel having a second average section, each third cooling channel having a third average section, the sections being considered in a plane orthogonal to the direction in which the cooling fluid circulates, the fourth average section being between 60% and 90% of the second average section and / or the fourth average section being between 60% and 90% of the third average section.
[0013] According to one embodiment, the assembly comprises a distribution plate comprising an external face intended to face an interface plate with an inlet and outlet pipe for the cooling fluid and with an inlet and outlet pipe for the reactive fluid, the distribution plate comprising an internal face fixed to the cooling face of the first end plate, the internal face and the cooling face of the first end plate defining between them reliefs and hollows to form a fifth cooling circuit for the circulation of the cooling fluid, the internal face being in particular glued or welded to the cooling face of the first end plate,the assembly being configured so that the volume flow rate of the cooling fluid passing through the fifth cooling circuit is lower than the volume flow rate of cooling fluid passing through the first cooling circuit, for example lower by 30% to 55%.
[0014] According to one embodiment, the fifth cooling circuit comprises a plurality of fifth cooling channels, each fifth cooling channel having a fifth average section, the section being considered in a plane orthogonal to the direction in which the cooling fluid circulates, the fifth average section being between 60% and 90% of the first average section.
[0015] According to one embodiment, the fifth average section is between 60% and 90% of the second middle section.
[0016] According to one embodiment, the fifth average section is between 60% and 90% of the third average section.
[0017] According to one embodiment, the closure plate is devoid of a through hole for the passage of the cooling fluid through the closure plate or for the passage of the reactive fluid through the closure plate.
[0018] According to one embodiment, each plate comprises a reagent inlet manifold formed through the plate and being in fluid communication with the reagent circuit, a reagent outlet manifold formed through the plate and being in fluid communication with the reagent circuit, a cooling fluid inlet manifold formed through the plate, a cooling fluid outlet manifold formed through the plate.
[0019] According to one embodiment, the closure face is fixed to the cooling face of the last end plate so as to form between them a first sealing bead, at least a portion of which forms a loop around the cooling fluid inlet manifold.
[0020] According to one embodiment, the closure face is fixed to the cooling face of the last end plate so as to form between them a second sealing bead, at least a portion of which forms a loop around the cooling fluid outlet manifold.
[0021] According to one embodiment, the sealing face is fixed to the cooling face of the last end plate so as to form a third sealing bead of which at least a portion forms a loop around the last cooling circuit.
[0022] According to one embodiment, the first, second and third cords are arranged to allow the cooling fluid entering through the cooling fluid inlet manifold to circulate only in the last cooling circuit and to exit only through the cooling fluid outlet manifold.
[0023] According to one embodiment, the sealing face is fixed to the cooling face of the last end plate so as to form a fourth sealing bead of which at least a portion forms a loop around the reagent inlet manifold.
[0024] According to one embodiment, the fourth sealing bead is arranged so as to allow the reactive fluid entering through the reactive inlet manifold to flow only towards the reactive face.
[0025] According to one embodiment, the sealing face is fixed to the cooling face of the last end plate so as to form a fifth sealing bead of which at least a portion forms a loop around the reagent outlet manifold.
[0026] According to one embodiment, the fifth sealing bead is arranged so as to allow the reactive fluid circulating on the reactive face to only exit through the reagent outlet manifold.
[0027] According to one embodiment, the distribution plate comprises a plurality of through holes, respectively for the passage of the cooling fluid and the reactive fluid through the distribution plate, in particular so as to allow distribution of these fluids, from the interface plate to the first end plate.
[0028] According to one embodiment, the internal face is fixed to the cooling face of the first end plate so as to form between them a sixth sealing bead of which at least one portion forms a loop around the cooling fluid inlet manifold, and / or a seventh sealing bead of which at least one portion forms a loop around the cooling fluid outlet manifold, and / or an eighth sealing bead of which at least one portion forms a loop around the reactive fluid inlet manifold, and / or a ninth sealing bead of which at least one portion forms a loop around the reactive fluid inlet manifold.
[0029] According to one embodiment, the internal face is fixed to the cooling face of the first end plate so as to form between them a tenth sealing bead, at least a portion of which forms a loop around the first cooling circuit.
[0030] According to one embodiment, the sixth cord is arranged so as to allow the cooling fluid entering through the cooling fluid inlet manifold to circulate only through said manifold and into the first cooling circuit.
[0031] According to one embodiment, the seventh sealing bead is arranged so as to allow the cooling fluid circulating in the first cooling circuit to exit only through the cooling fluid outlet manifold.
[0032] According to one embodiment, the cooling face of the cathode plate of at least one of the cells is fixed, in particular glued and / or welded, to the cooling face of the anode plate of another of the cells, so as to form a seal in particular around the first, second or third cooling circuit.
[0033] Alternatively, a seal is interposed between the cooling face of the cathode plate of at least one of the cells and the cooling face of the anode plate of another of the cells.
[0034] The invention further relates to a fuel cell comprising an assembly as described above, a first electric current collector plate, a second electric current collector plate and an interface plate with an inlet and outlet pipe for the cooling fluid and the reactive fluid.
[0035] According to one embodiment, the battery comprises a first electrically insulating plate and a first clamping plate, the first electrically insulating plate being arranged between the first collector plate and the first clamping plate.
[0036] According to one embodiment, the battery comprises a second electrically insulating plate and a second clamping plate, the second electrically insulating plate being arranged between the second collector plate and the second clamping plate.
[0037] The invention will be better understood by reading the following description and examining the figures. These figures are given only for illustrative purposes but in no way limit the invention.
[0038] [Fig-1] [Fig.l] is a schematic perspective representation of a set according to the invention;
[0039] [Fig.2] [Fig.2] is a schematic representation of a detail of the assembly according to the invention;
[0040] [Fig.3] [Fig.3] is a schematic representation of a detail of the assembly according to the invention; and
[0041] [Fig.4] [Fig.4] is a schematic representation of a battery according to the invention.
[0042] Identical, similar, or analogous elements retain the same reference from one figure to another.
[0043] [Fig.l] represents an assembly 1 comprising a stack of a plurality of proton exchange membrane fuel cell cells 30.
[0044] The plurality of cells 30 comprises a first cell 30 at a first end of the stack and a last cell 30 at a second end of the stack.
[0045] Each cell 30 of the plurality comprises an anode plate 10 and a cathode plate 20 sandwiching a Membrane Electrode Assembly 16.
[0046] Each plate 10, 20 comprises a reactive face and a cooling face opposite one another, the reactive face of each plate 10, 20 being intended to face the Membrane Electrode Assembly 16 and being provided with reliefs and hollows forming a reactive circuit, for the circulation of a reactive fluid.
[0047] As visible in [Fig.l], the cooling face of the cathode plate 20 of at least one of the cells 30 is intended to face the cooling face of the anode plate 10 of another of the cells 30, defining between them reliefs and hollows to form a first cooling circuit 15 for the circulation of a cooling fluid.
[0048] In the example of [Fig.l], each plate 10, 20 comprises: - a reagent inlet manifold 3, 4 formed through the plate 10, 20 and being in fluid communication with the reagent circuit via a first lumen 2 formed through the plate 10, 20; - a reagent outlet manifold 6, 7 formed through the plate 10, 20 and being in fluid communication with the reagent circuit via a second lumen 2 formed through the plate 10, 20; - a cooling fluid inlet manifold 5 formed through the plate 10, 20; - a cooling fluid outlet manifold 8, 9 formed through the plate 10, 20. - at least two orifices formed through the plate 10, 20, each orifice being arranged to allow fluid communication only through the plate 10, 20, without being in fluid communication with the reagent circuit.
[0049] The reagent inlet manifold 3 of an anode plate 10 is in fluid communication with one of the orifices of a cathode plate 20 and the reagent outlet manifold 6 of the anode plate 10 is in fluid communication with another of the orifices of the cathode plate 20.
[0050] The reagent inlet manifold 3 of a cathode plate 20 is in fluid communication with one of the orifices of an anode plate 10 and the reagent outlet manifold 6 of the cathode plate 20 is in fluid communication with another of the orifices of the anode plate 10.
[0051] Thus, the stack allows distribution of the reactive fluid dedicated to the anode plates 10 and distribution of the reactive fluid dedicated to the cathode plates 20 by forming two independent circuits.
[0052] One of the plates 10, 20 of the first cell 30 forms with one of the plates 10, 20 of another of the cells 30, a second cooling circuit 15 and the other of the plates 10, 20 of the first cell 30 forms a first end plate.
[0053] One of the plates 10, 20 of the last cell 30 forms with one of the plates 10, 20 of another of the cells 30, a third cooling circuit 15 and the other of the plates 10, 20 of the last cell 30 forms a last end plate.
[0054] As shown in [Fig.l], the assembly 1 comprises a closure plate 21 comprising an electric current collection face intended to face a first electric current collector plate and a closure face fixed to the cooling face of the last end plate, the closure face and the cooling face of the last end plate defining between them reliefs and hollows to form a fourth cooling circuit for the circulation of the cooling fluid.
[0055] The assembly 1 further comprises a distribution plate 11 comprising an external face intended to face an interface plate 17 with an inlet and outlet pipe for the cooling fluid and with an inlet and outlet pipe for the reactive fluid, the distribution plate comprising an internal face fixed to the cooling face of the first end plate, the internal face and the cooling face of the first end plate defining between them reliefs and hollow to form a fifth cooling circuit for the circulation of the coolant.
[0056] In the example of [Fig.l], the closure face is welded to the cooling face of the last end plate and the inner face is welded to the cooling face of the first end plate.
[0057] In the example shown in [Fig.l], the closure face of the closure plate 21 comprises a reagent passage 12, 13 formed by reliefs and hollows, to allow fluid communication between the reagent inlet manifold 3, 4 and the reagent circuit or to allow fluid communication between the reagent outlet manifold 6, 7 and the reagent circuit.
[0058] The closure face of the closure plate 21 comprises a cooling passage 13 formed by reliefs and hollows, to allow fluid communication between the cooling fluid inlet manifold 5 and the cooling circuit or to allow fluid communication between the cooling fluid outlet manifold 8, 9 and the cooling circuit.
[0059] The reagent passage 12, 13 and the cooling passage 13 can be provided at the closure face, at the last end plate or even on both.
[0060] [Fig.2] represents a detail of the stack of [Fig.l].
[0061] As shown in [Fig.2], the cooling face of the cathode plate 20 of a cell 30 faces the cooling face of the anode plate 10 of an adjacent cell 30, defining between them reliefs and hollows to form the first cooling circuit 15 for the circulation of a cooling fluid.
[0062] The first cooling circuit 15 comprises a plurality of first cooling channels 31. In the example shown, each first cooling channel 31 has a first average section substantially in the shape of a rectangle having a width L1 and a height HL. By definition, the first section is considered in a plane orthogonal to the direction in which the cooling fluid circulates.
[0063] In an exemplary embodiment, the width L1 is equal to 1.5 mm and the height H1 is equal to 0.50 mm. Thus, the first average section has a surface area of 0.75 mm2.
[0064] [Fig. 3] shows another detail of the stack of [Fig. 1], namely a portion of the last end plate 40 and the closure plate 21.
[0065] As shown in [Fig.3], the closure face 42 of the closure plate 21 and the cooling face of the last end plate 40 define between them reliefs and hollows to form the fourth cooling circuit 43 for the circulation of the cooling fluid.
[0066] The fourth cooling circuit 43 comprises a plurality of fourth cooling channels 44.
[0067] The assembly 1 is configured so that the volume flow rate of the cooling fluid passing through the fourth cooling circuit 43 is lower than the volume flow rate of cooling fluid passing through the first cooling circuit 15, for example lower by 30% to 55%, the volume flow rates being considered for the same speed of the cooling fluid.
[0068] In the example shown, each fourth cooling channel 44 has a fourth average section substantially in the shape of a rectangle having a width L2 and a height H2. By definition, the fourth section is considered in a plane orthogonal to the direction in which the cooling fluid circulates.
[0069] In an exemplary embodiment, the width L2 is equal to 1.5 mm and the height H2 is equal to 0.40 mm. Thus, the fourth average section has a surface area of 0.60 mm2.
[0070] In the example considered, the fourth average section is equal to 80% of the first average section.
[0071] [Fig.4] represents a fuel cell comprising an assembly as described above.
[0072] The battery comprises a first collector plate, for collecting an electric current, the first collector plate having one face in contact with the collection face of the closure plate 21 and its opposite face in contact with a first electrically insulating plate 18.
[0073] The first collector plate is arranged to fit into a receiving zone provided on the collection face of the closure plate 21.
[0074] The stack further comprises an interface plate 17 with an inlet and outlet pipe for the cooling fluid and the reactive fluid.
[0075] The battery comprises a second electrically insulating plate. This second electrically insulating plate can be either in the form of an element separate from the interface plate 17 and in contact with the interface plate 17, or the interface plate 17 acts as a second electrically insulating plate, in particular by one of its faces in contact with the distribution plate 11.
[0076] All of the pipes are thus arranged on the same side of the stack, the other side being closed by the closing plate 21.
[0077] In the example shown, the first end plate is an anode plate 10 and the last end plate is a cathode plate 20. Alternatively, the first end plate is a cathode plate 20 and the last end plate is an anode plate 10.
[0078] The assembly 1 is arranged so that all of the fluid inlet and outlet pipes are arranged on the side of only one of the ends of the stack. Thus, the closure plate 21 is a plate which closes all of the collectors and the holes in the last end plate. Such a closure plate 21 makes it possible to present a flat face for collecting the electric current generated by the battery.
Claims
Claims
1. An assembly (1) comprising a stack of a plurality of proton exchange membrane fuel cell cells (30), the plurality of cells (30) comprising a first cell (30) at a first end of the stack and a last cell (30) at a second end of the stack, each cell (30) of the plurality comprising an anode plate (10) and a cathode plate (20) sandwiching a Membrane Electrode Assembly (16), each plate (10, 20) comprising a reactive face and a cooling face opposite each other, the reactive face of each plate (10, 20) being intended to face the Membrane Electrode Assembly (16) and being provided with reliefs and hollows forming a reactive circuit, for the circulation of a reactive fluid,the cooling face of the cathode plate (20) of at least one of the cells (30) being intended to face the cooling face of the anode plate (10) of another of the cells (30), defining between them reliefs and hollows to form a first cooling circuit (15) for the circulation of a cooling fluid, the first cooling circuit (15) comprising a plurality of first cooling channels (31), one of the plates (10, 20) of the first cell (30) forming with one of the plates (10, 20) of another of the cells (30), a second cooling circuit (15) for the circulation of the cooling fluid, the second cooling circuit (15) comprising a plurality of second cooling channels, the other of the plates (10, 20) of the first cell (30) forming a first end plate, one of the plates (10, 20) of the last cell (30) forming with one plates (10,20) of another of the cells (30), a third cooling circuit (15) for circulating the cooling fluid, the third cooling circuit (15) comprising a plurality of third cooling channels, the other of the plates (10, 20) of the last cell (30) forming a last end plate (40), the assembly (1) comprising a closure plate (21) comprising an electric current collecting face (41) intended to face a first electric current collecting plate and a closure face (42) fixed to the cooling face of the last end plate (40), the closure face (42) and the cooling face of the last, end plate (40) defining between them reliefs and hollows to form a fourth cooling circuit (43) for the circulation of the cooling fluid, the fourth cooling circuit (43) comprising a plurality of fourth cooling channels (44), the assembly (1) being configured so that the volume flow rate of the cooling fluid passing through the fourth cooling circuit (43) is lower than the volume flow rate of cooling fluid passing through the first cooling circuit (15), for example lower by 30% to 55%, the volume flow rates being considered for the same speed of the cooling fluid.
2. Assembly (1) according to the preceding claim, the closure face being glued or welded to the cooling face of the last end plate.
3. Assembly (1) according to one of the preceding claims, being configured so that the volume flow rate of the cooling fluid passing through the fourth cooling circuit (43) is lower than the volume flow rate of cooling fluid passing through the second cooling circuit (15), for example lower by 30% to 55%, the volume flow rates being considered for the same speed of the cooling fluid and / or being configured so that the volume flow rate of the cooling fluid passing through the fourth cooling circuit (43) is lower than the volume flow rate of cooling fluid passing through the third cooling circuit (15), for example lower by 30% to 55%, the volume flow rates being considered for the same speed of the cooling fluid.
4. Assembly (1) according to one of the preceding claims, each first cooling channel (31) having a first average section, each fourth cooling channel (44) having a fourth average section, the sections being considered in a plane orthogonal to the direction in which the cooling fluid circulates, the fourth average section being between 60% and 90% of the first average section.
5. Assembly (1) according to the preceding claim, each second cooling channel having a second average section, each third cooling channel having a third average section, the sections being considered in a plane orthogonal to the direction in which the cooling fluid circulates, the fourth average section being between 60% and 90% of the second section average and / or the fourth average section being between 60% and 90% of the third average section.
6. Assembly (1) according to one of the preceding claims, comprising a distribution plate (11) comprising an external face intended to face an interface plate (17) with an inlet and outlet pipe for the cooling fluid and with an inlet and outlet pipe for the reactive fluid, the distribution plate (11) comprising an internal face fixed to the cooling face of the first end plate, the internal face and the cooling face of the first end plate defining between them reliefs and hollows to form a fifth cooling circuit for the circulation of the cooling fluid, the internal face being in particular glued or welded to the cooling face of the first end plate,the assembly (1) being configured so that the volume flow rate of the cooling fluid passing through the fifth cooling circuit is lower than the volume flow rate of cooling fluid passing through the first cooling circuit, for example lower by 30% to 55%,
7. / 0. Assembly (1) according to the preceding claim, the fifth cooling circuit comprising a plurality of fifth cooling channels, each fifth cooling channel having a fifth average section, the section being considered in a plane orthogonal to the direction in which the cooling fluid circulates, the fifth average section being between 60% and 90% of the first average section.
8. Fuel cell comprising an assembly (1) according to any one of the preceding claims, a first electric current collector plate, a second electric current collector plate and an interface plate (17) with an inlet and outlet pipe for the cooling fluid and the reactive fluid.