Cell for an electrochemical energy converter

Abstract

The invention relates to a cell (100) for an electrochemical energy converter (300), wherein the cell (100) comprises: a first polar plate element (101); a second polar plate element (103); a membrane electrode assembly (MEA) (105); a frame (107) surrounding the MEA (105); and a seal (109), wherein the MEA (105), the frame (107) and the seal (109) are arranged between the first polar plate element (101) and the second polar plate element (103), wherein the MEA (105) comprises an elastic element (111), and wherein the elastic element (111) overlays the seal (109).

Description

[0001] R.415620

[0002] - 1 -

[0003] Description

[0004] title

[0005] Cell for an electrochemical

[0006] The invention presented relates to a cell for an electrochemical energy converter, a method for manufacturing the presented cell and an electrochemical energy converter according to the attached claims.

[0007] State of the art

[0008] Stacked arrangements of electrochemical cells for use in an electrochemical energy converter, such as a fuel cell system or an electrolysis system, are known.

[0009] Each cell of such a stacked arrangement has a layered structure, which usually includes an electrically insulating and chemically separating but ion-conducting composite polymer membrane with a corresponding (cathode and anode) electrode / catalyst layer on each side where the actual electrochemical reaction takes place.

[0010] Disclosure of the invention

[0011] Within the scope of the presented invention, a cell for an electrochemical energy converter, a method for manufacturing the cell according to the invention, and an electrochemical energy converter are presented. Further features and details of the invention will become apparent from the respective dependent claims, the description, and the drawings. Features and details described in connection with the cell according to the invention naturally also apply in connection with the method and the electrochemical converter according to the invention. R.415620

[0012] - 2 -

[0013] Energy converters and vice versa, so that with regard to the disclosure of the individual aspects of the invention, mutual reference is always made or can be made.

[0014] The presented invention serves in particular to provide a robust electrochemical energy converter.

[0015] Thus, according to a first aspect of the presented invention, a cell for an electrochemical energy converter is presented.

[0016] The presented cell comprises a first polar plate element, a second polar plate element, a membrane electrode assembly (MEA), a frame surrounding the MEA, and a terrace seal, wherein the MEA, the frame, and the terrace seal are arranged between the first polar plate element and the second polar plate element, wherein the MEA includes an elastic element, and wherein the elastic element overlays the terrace seal.

[0017] In the context of the presented invention, an elastic element superimposed on a terrace seal is understood to be an elastic element that is aligned in the Y-direction, particularly in the direction of gravity, above or below the terrace seal. At least one further element, such as a portion of a membrane and / or a porous transport layer (PTL) or gas diffusion layer (GDL), may be arranged between the elastic element and the terrace seal.

[0018] In the context of the invention presented, a polar plate element is to be understood as at least a part of a bipolar plate.

[0019] The presented invention is based on the principle that an elastic element, such as a corrugated part that can be reversibly deformed in the direction of the terrace seal, is integrated into the MEA of the presented cell, in particular inserted into a PTL or GDL of the MEA. For this purpose, the PTL or GDL can form a receptacle for the elastic element, into which the R.415620

[0020] - 3 - elastic element can be used, or the elastic element can be inserted into the PTL or GDL.

[0021] Alternatively, the elastic element can be monolithically integrated into the ME A.

[0022] The elastic element cushions or buffers pressure exerted on the cell from the surrounding environment, thus minimizing deformation of the terrace seal.

[0023] Furthermore, the elastic element presses the MEA against both the terrace seal and the first polar plate element, thus compensating for age-related deformations of the terrace seal and maintaining direct contact between the MEA and the terrace seal throughout the cell's lifetime. Consequently, the sealing effect of the terrace seal against the anode side of the cell does not diminish over the cell's lifetime; rather, the sealing effect remains constant.

[0024] The elastic element provided according to the invention can comprise a mechanical spring, such as a wave-shaped core or any other technically suitable elastic component.

[0025] The elastic element provided according to the invention can comprise an elastic core surrounded by deformable material, such as porous material of a PTL.

[0026] It may be provided that the frame comprises a base body forming a frame terrace and an edge element, wherein the height of the frame terrace is less than the height of the edge element of the frame.

[0027] A stepped frame structure is achieved by using a frame terrace whose height is less than the height of the frame's edge element. Accordingly, the MEA can be placed on the frame terrace and essentially flush with the edge element, so that the R.415620

[0028] - 4 - second polar plate element rests on the ME A and the edge element and seals the cell accordingly against an environment.

[0029] In particular, the MEA may include a porous transport layer (PTL), a gas diffusion layer (GDL) and a membrane arranged between the PTL and GDL, wherein the PTL comprises a first intermediate layer and a second intermediate layer, the first intermediate layer extending over the frame terrace to the edge element, and the elastic element being arranged on the first intermediate layer between the second intermediate layer and the edge element of the frame.

[0030] Various intermediate layers can provide a receptacle for receiving the elastic element, making it easy and quick to produce the proposed cell by forcing the elastic element through the various intermediate layers into its predetermined position above the terrace seal.

[0031] It may also be provided that the elastic element is arranged flush with an end of the frame terrace opposite the edge element.

[0032] An aligned arrangement of the elastic element with an end of the frame terrace opposite the edge element results in elastic behavior of the MEA in the area of ​​the frame terrace, especially in the area of ​​the terrace seal, so that a reliable seal of the cell is achieved over its lifetime.

[0033] It may also be provided that the elastic element has a wave-shaped profile.

[0034] A wave-like profile of the elastic element ensures the flow of operating fluids, such as anode water, to the active surface of the cell. R.415620

[0035] - 5 -

[0036] It may also be provided that the terrace seal is mechanically decoupled from any pressure acting on the cell by the elastic element.

[0037] By arranging the elastic element superimposed on the terrace seal, the elastic element absorbs or buffers any pressure acting on the cell before it is transferred to the terrace seal, thus protecting the terrace seal from high mechanical stress and ensuring its longevity.

[0038] It can also be provided that the frame is one piece and the elastic element is one piece.

[0039] A one-piece frame and a one-piece elastic element are particularly stable and durable due to the lack of connection points between the respective parts.

[0040] It may also be provided that the frame is multi-part and the elastic element is multi-part.

[0041] A multi-part frame can be manufactured particularly cost-effectively, as material removal is reduced compared to a manufacturing process for a one-piece frame.

[0042] Accordingly, a one-piece elastic element can also be manufactured particularly cost-effectively, since material removal is reduced compared to a manufacturing process for a one-piece elastic element.

[0043] It may also be provided that the elastic element is arranged adjacent to at least one flow channel formed in the frame.

[0044] A number of flow channels in the frame can, for example, be used to guide operating fluid through the frame. Accordingly, operating fluid, especially water, can be drawn through the number of flow channels via the R.415620.

[0045] - 6 - The elastic element, or a space in which the elastic element is arranged, can be directed into the PTL. Conversely, operating fluid, in particular water, can be discharged from the PTL, via the elastic element or a space in which the elastic element is arranged, into the number of flow channels and, consequently, through the frame. The respective flow channels can be shaped in such a way that they redirect the flow direction of the operating fluid.

[0046] The at least one flow channel can, for example, comprise a fan channel that distributes a fluid flowing in the z-direction through a corresponding cell stack into the xy-plane of the individual cells. Accordingly, the elastic element optimizes a uniform distribution of operating fluids, especially water, within a cell.

[0047] According to a second aspect, the presented invention relates to a method for manufacturing a cell for an electrochemical energy converter.

[0048] The presented method comprises arranging a frame on a first polar plate element, wherein the frame comprises a base body forming a frame terrace and an edge element higher relative to the frame terrace, arranging a terrace seal on the frame terrace, arranging a membrane electrode assembly (MEA) on the frame terrace and on the first polar plate element, and arranging a second polar plate element on the MEA and the edge element, wherein the MEA comprises an elastic element, and wherein the MEA is arranged on the frame terrace and the first polar plate element such that the elastic element overlaps the terrace seal.

[0049] According to a third aspect, the presented invention relates to an electrochemical energy converter for converting energy, wherein the electrochemical energy converter comprises a number of possible embodiments of the presented cell.

[0050] The electrochemical energy converter may be a fuel cell system or an electrolysis system. R.415620

[0051] - 7 -

[0052] In particular, the presented electrochemical energy converter can be a PEM, AEM electrolysis system, e.g. a carbon dioxide electrolysis system.

[0053] The presented method is particularly suitable for the production of the presented cell for use in the presented electrochemical energy converter.

[0054] Advantages described in detail for the cell for an electrochemical energy converter according to the first aspect of the invention apply equally to the method for manufacturing a cell for an electrochemical energy converter according to the second aspect of the invention and to the electrochemical energy converter for converting energy according to the third aspect of the invention, and vice versa.

[0055] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can each be essential to the invention individually or in any combination.

[0056] They each show schematically:

[0057] Figure 1 shows a representation of a possible design of the cell presented.

[0058] Figure 2 shows a possible embodiment of the presented method and

[0059] Figure 3 shows a possible embodiment of the presented electrochemical

[0060] Energy converter.

[0061] Fig. 1 shows a cell 100 for an electrochemical energy converter 300.

[0062] The presented cell 100 comprises a first polar plate element 101, a second polar plate element 103, an R.415620

[0063] - 8 -

[0064] Membrane electrode assembly (MEA) 105, a frame 107 surrounding the MEA 105, and a terrace seal 109.

[0065] The MEA 105, the frame 107 and the terrace seal 109 are arranged between the first polar plate element 101 and the second polar plate element 103.

[0066] The MEA 105 includes an elastic element 111 that overlays the terrace seal 109.

[0067] In the present case, MEA 105 comprises, by way of example, a porous transport layer 113, which in turn comprises a first intermediate layer 115 and a second intermediate layer 117, wherein the first intermediate layer 115 extends over a frame terrace 119 to an edge element 121 of the frame 107.

[0068] The elastic element 111 is placed on the first intermediate layer 115 and arranged between the second intermediate layer 117 and the edge element 121 of the frame 107.

[0069] The elastic element 111 comprises a wave-shaped elastic core 123, through which a flow of operating media, such as anode water, to the active surface of the cell 100 is ensured.

[0070] Furthermore, the MEA 105 includes a gas diffusion layer (GDL) 125 and a membrane 127.

[0071] Furthermore, the cell 100 optionally includes a number of flow channels 129 through which operating fluid, in particular water, flows between the porous

[0072] Transport layer 113 and an environment of cell 100, through frame 121, is guided.

[0073] In particular, the number of flow channels 129 defines a flow path along which the operating fluid flows between the porous transport layer 113 and the environment of the cell 100. Since this flow path passes through the elastic element 111 or a space in which the elastic element 111 is arranged (R.415620)

[0074] - 9 - is, leads, promotes a particularly rapid and correspondingly homogeneous distribution of the operating fluid in the cell 100. In Fig. 2 a method 200 for the production of the cell 100 according to Fig. 1 is shown.

[0075] The method 200 comprises a first arrangement step 201 in which a frame 107 is arranged on a first polar plate element 101, wherein the frame 107 comprises a base body forming a frame terrace 119 and an edge element 121 that is higher relative to the frame terrace 119.

[0076] The method 200 further comprises a second arrangement step 203 in which a terrace seal 109 is arranged on the frame terrace 119, a third arrangement step 205 in which a membrane electrode unit (MEA) 105 is arranged on the frame terrace 119 and on the first polar plate element 101, and a fourth arrangement step 207 in which a second polar plate element 103 is arranged on the MEA 105 and the edge element 121, wherein the MEA 105 comprises an elastic element 111, and wherein the MEA 105 is arranged on the frame terrace 119 and the first polar plate element 101 such that the elastic element 111 overlaps the terrace seal 109.

[0077] Figure 3 shows an electrochemical energy converter 300. The electrochemical energy converter 300 comprises a cell stack 301 in which a plurality of the cells 100 according to Figure 1 are arranged.

Claims

R.415620 - 10 - Claims 1. Cell (100) for an electrochemical energy converter (300), wherein the cell (100) comprises: a first polar plate element (101), a second polar plate element (103), a membrane electrode assembly (MEA) (105), a frame (107) surrounding the MEA (105), and a terrace seal (109), wherein the MEA (105), the frame (107), and the terrace seal (109) are arranged between the first polar plate element (101) and the second polar plate element (103), wherein the MEA (105) comprises an elastic element (111), and wherein the elastic element (111) overlays the terrace seal (109).

2. Cell (100) according to claim 1 , characterized in that the frame (107) comprises a base body forming a frame terrace (119) and an edge element (121), wherein the height of the frame terrace (119) is less than the height of the edge element (121) of the frame (107). R.415620 - 11 - 3. Cell (100) according to claim 2, characterized in that the MEA (105) comprises a porous transport layer (PTL) (113), a gas diffusion layer (GDL) (125) and a membrane (127) arranged between PTL (113) and GDL (125), wherein the PTL (113) comprises a first intermediate layer (115) and a second intermediate layer (117), wherein the first intermediate layer (115) extends over the frame terrace (119) to the edge element (121) of the frame (107), and wherein the elastic element (111) is arranged on the first intermediate layer (115) between the second intermediate layer (117) and the edge element (121) of the frame (107).

4. Cell (100) according to claim 3, characterized in that the elastic element (111) is arranged in alignment with an end of the frame terrace (119) opposite the edge element (121).

5. Cell (100) according to one of the preceding claims, characterized in that the elastic element (111) has a wave-shaped profile.

6. Cell (100) according to one of the preceding claims, characterized in that the terrace seal (109) is mechanically decoupled from a pressure acting on the cell (100) by the elastic element (111).

7. Cell (100) according to one of the preceding claims, characterized in that the frame (107) is one piece and the elastic element (111) is one piece. R.415620 - 12 - 8. Cell (100) according to one of the preceding claims, characterized in that the frame (107) is multi-part and the elastic element (111) is multi-part.

9. Cell (100) according to one of the preceding claims, characterized in that the elastic element (111) is arranged adjacent to at least one flow channel (129) formed in the frame (107).

10. Method (200) for manufacturing a cell (100) for an electrochemical energy converter (300), wherein the method (200) comprises: Arranging (201) a frame (107) on a first polar plate element (101), wherein the frame (107) comprises a base body forming a frame terrace (119) and an edge element (121) higher relative to the frame terrace (119), Arranging (203) a terrace seal (109) on the frame terrace (119), Arranging (205) a membrane electrode assembly (MEA) (105) on the frame terrace (119) and on the first polar plate element (101) and Arranging (207) a second polar plate element (103) on the MEA (105) and the edge element (121), wherein the MEA (105) comprises an elastic element (111), and wherein the MEA (105) is arranged on the frame terrace (119) and the first polar plate element (101) such that the elastic Element (111) overlaps the terrace seal (109).

11. Electrochemical energy converter (300) for converting energy, wherein the electrochemical energy converter (300) comprises a number of cells (100) according to any one of claims 1 to 9.

12. Electrochemical energy converter (300) according to claim 11, characterized in that, R.415620 - 13 - that the electrochemical energy converter (300) is a fuel cell system or an electrolysis system.

Images