Bipolar plate, fuel cell system, and electrolytic cell

Abstract

The invention to be proposed is a bipolar plate (100) for a chemical energy converter (200, 300). The bipolar plate (100) comprises: - a number of passages (101) for guiding the working medium of the energy converter (200, 300); - a number of supply openings (103) for supplying the working medium to the number of passages (101); - a number of distribution passages (105) for distributing the working medium to the number of passages (101), each distribution passage (105) of the number of distribution passages (105) extending between each supply opening (103) of the number of supply openings (103) and each passage (101) of the number of passages (101), and each supply opening (103) of the number of supply openings (103) having an edge region in which at least a part of the region is bent on at least the distribution passage side facing each distribution passage (105) of the number of distribution passages (105).

Description

Technical Field

[0001] The present invention relates to a bipolar plate, a fuel cell system, and an electrolytic cell.

Background Art

[0002] In order to achieve the best possible performance of an energy converter, in the cells of an energy converter, such as an electrolytic cell or a fuel cell system, etc., it is necessary to uniformly distribute each operating medium, such as an extract, etc., to the reaction surface of each cell. In order to distribute the operating medium provided through a supply opening, i.e., a so-called "port", onto the reaction surface, distribution channels arranged in a distribution field are usually used.

[0003] Supply openings of the same size as the distribution field usually lead to mechanically fragile bipolar plates, so such supply openings need to be reinforced by webs. However, such webs act disadvantageously on the volume flow flowing out of each supply opening.

Summary of the Invention

[0004] In the scope of the present invention, a bipolar plate, a fuel cell system, and an electrolytic cell are presented. Other features and details of the present invention will become apparent from the respective dependent claims, this description, and the drawings. In that case, the features and details described in connection with the bipolar plate according to the present invention are, of course, also valid in connection with the fuel cell system according to the present invention or the electrolytic cell according to the present invention, and vice versa, whereby the disclosures of the individual aspects of the invention are always cross-referenced to each other, or can be.

[0005] The present invention is particularly used to enable an energy converter to operate efficiently and robustly.

[0006] Accordingly, according to a first aspect of the present invention, a bipolar plate for a chemical energy converter, such as a fuel cell or an electrolytic cell, etc., is presented.

[0007] The bipolar plates to be presented include a number of passages for guiding the operating medium of the energy converter, a number of supply openings for supplying the operating medium to the number of passages, and a number of supply openings for distributing the operating medium provided through the number of supply openings to the number of passages. Each of the distribution passages of the number of distribution passages extends between each of the supply openings of the number of supply openings and each of the passages of the number of passages. Each of the supply openings of the number of supply openings has an edge region in which at least a part of the region is bent on at least the distribution passage side facing each of the distribution passages of the number of distribution passages.

[0008] In the context of the present invention, the supply opening can be understood as a so-called "port" that supplies an operating medium such as fuel or water to the bipolar plate during operation.

[0009] In the context of the present invention, the distribution passage can be understood as a flow guiding device that guides the operating medium flowing out of the supply opening to each passage or reaction field of the bipolar plate. The distribution passage can be integrally formed from the passage or can be a separate unit, particularly made of a material different from each passage of the bipolar plate. Of course, the distribution passage can also be made of the same material as each passage of the bipolar plate.

[0010] The present invention is based on the principle that each of the supply openings of the number of supply openings has a bent edge region on at least the distribution passage side facing each of the distribution passages of the number of distribution passages.

[0011] The bent edge region of the supply passage of the bipolar plate to be presented enables the distribution passage to be arranged such that the working medium is evenly supplied thereto even when the distribution passage surrounds each web for stabilizing the bipolar plate. Accordingly, a so-called "flow shadow (Flussschatten)", i.e., a negative influence on the flow behavior of the working medium flowing out of the distribution opening (Verteilungsoeffnung), is prevented or minimized.

[0012] Furthermore, the bent edge region of the supply passage enables particularly advantageous flow dynamics in the distribution field with a particularly compact distribution field geometry.

[0013] It can be contemplated that all distribution passages have the same length. By the distribution passages of the same length, an even supply of the presented bipolar plate to the passages is ensured by the distribution passages. In that case, the bent edge region of the supply opening enables the distribution passages to have the same length and to surround each stabilizing web.

[0014] Furthermore, each supply opening can be contemplated to be adjacent to each distribution passage on the distribution passage side, and each distribution passage to extend from each supply opening to each passage.

[0015] By directing the bent distribution passage side of each supply opening towards each distribution passage, an additional space or additional area is provided by which the bent edge region of the supply opening enables the distribution passage to extend as compared to a straight edge region.

[0016] Furthermore, each distribution passage can be contemplated to extend at least partially obliquely between the distribution passage side and each passage.

[0017] By having the distribution channels extend obliquely, i.e., at an acute angle or at an angle less than 90° with respect to the vertical axis of the bipolar plate for example, each distribution channel can surround the stabilizing web around the stabilizing web or pass by the stabilizing web in the edge region of the stabilizing web, whereby the influence of the stabilizing web on the flow behavior of the medium flowing through the distribution channels is minimized. In that case, the vertical axis can extend parallel to the long side of the bipolar plate for example.

[0018] Of course, the numerous distribution channels contemplated by the present invention can include straight, i.e., distribution channels extending parallel to the vertical axis, and oblique distribution channels. In particular, each distribution channel adjacent to the stabilizing web can extend obliquely, and the distribution channels arranged in the central region of each distribution field can extend straight.

[0019] Furthermore, it can be contemplated that the angle between each distribution channel and the vertical axis of the bipolar plate is different from the angle between another distribution channel and the vertical axis.

[0020] By arranging the distribution channels at various angles, i.e., with individual inclinations or slopes of the distribution channels, with respect to the vertical axis of the bipolar plate presented, the inclination of the distribution channels can be adjusted to match the radius of curvature of each distribution opening (Verteileroeffnung), whereby all distribution channels lead to the channels of the bipolar plate presenting the same or an equivalent volume flow of the operating medium regardless of the inclination of each distribution channel. Furthermore, it can be contemplated that the distribution channels and the channels are made of different materials.

[0021] Furthermore, it can be contemplated that the distribution channels are made of plastic and the channels are made of metal.

[0022] In order to ensure the accurate shaping of the distribution channels according to a predetermined arrangement contemplated by the present invention, the distribution channels can be made of a material that can be shaped particularly easily, for example, plastic. Accordingly, the distribution channels can be preconfigured in the form of a distribution field and introduced into the substrate of the bipolar plate presented, for example, made of metal.

[0023] Furthermore, it can be contemplated that the edge region of each supply opening is bent in the direction of the center of the supply opening.

[0024] By bending the edge region in the direction of the center of the supply opening, the area of the distribution channel extending between the edge region and each passage of the bipolar plate presented is maximized.

[0025] Furthermore, it can be contemplated that the bipolar plate comprises a plurality of stabilizing webs with a plurality of compensation channels, in particular for pressure compensation and / or flow compensation between the supply openings.

[0026] The stabilizing webs maximize the mechanical load-bearing capacity (Belastbarkeit) of the bipolar plate. By integrating the compensation channels into the stabilizing webs, a uniform distribution of pressure and / or flow forces (Stroemungskraefte) between the respective regions of the bipolar plate separated by the stabilizing webs is achieved.

[0027] According to a second aspect, the presented invention relates to a fuel cell system having a possible embodiment of the presented bipolar plate.

[0028] According to a third aspect, the presented invention relates to an electrolytic cell having a possible embodiment of the presented bipolar plate.

[0029] Other advantages, features, and details of the present invention will become apparent from the following description, which details exemplary embodiments of the present invention with reference to the drawings. In that case, the features mentioned in the claims and the description may each be essential to the invention, either alone or optionally in combination.

Brief Description of the Drawings

[0030]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0031] FIG. 1 shows a bipolar plate 100 for an energy converter such as, for example, a fuel cell system or an electrolyzer.

[0032] The bipolar plate 100 includes a number of passages 101 for guiding the operating medium of the energy converter. For example, the passages 101 form the reaction field or reaction region of the bipolar plate 100.

[0033] The bipolar plate 100 further includes a number of supply openings 103 for supplying the operating medium (singular or plural) to the passages 101, and a number of distribution passages 105 extending between the supply openings 103 and the passages 101.

[0034] The supply openings 103 have an edge region 107 bent on the distribution passage side facing the distribution passages 105.

[0035] In FIG. 1, it can also be well recognized that most of the distribution passages 105 extend obliquely with respect to the vertical axis 109. In that case, all the distribution passages 105 are of the same length and surround the stabilizing web 111.

[0036] Optionally, the stabilizing web 111 can comprise a compensation passage 117 that enables pressure compensation and flow compensation between the supply openings 103.

[0037] The distribution field 113 includes straight, i.e., vertically extending parallel to the vertical axis 109, distribution passages 105 only in the central region, and diagonal distribution passages 105 otherwise, while the distribution field 115 has diagonal distribution passages 105 only in the outer edge region and straight distribution passages 105 otherwise.

[0038] Based on the geometry of the distribution openings (Verteileroeffnungen) 103 and the distribution passages 105, the working medium is evenly supplied to the passage 101.

[0039] FIG. 2 shows a fuel cell system 200. The fuel cell system 200 includes a fuel cell stack 201 having a number of bipolar plates 100, as shown, for example, in FIG. 1.

[0040] FIG. 3 shows an electrolyzer 300. The electrolyzer 300 includes a cell stack 301 having a number of bipolar plates 100, as shown, for example, in FIG. 1.

Explanation of Reference Numerals

[0041] 100 Bipolar plate 101 Passage 103 Supply opening 105 Distribution passage 107 Edge region 109 Vertical axis 111 Stabilizing web 113 Distribution field 115 Distribution field 117 Compensation passage 200 Fuel cell system 201 Fuel cell stack 300 Electrolyzer 301 Cell stack

Claims

1. A bipolar plate (100) for a chemical energy converter (200, 300), comprising: - a plurality of passages (101) for guiding the working medium of the energy converter (200, 300); - a plurality of supply openings (103) for supplying the working medium to the plurality of passages (101); - a plurality of distribution passages (105) for distributing the working medium to the plurality of passages (101), each of the plurality of distribution passages (105) extending between a respective one of the plurality of supply openings (103) and a respective one of the plurality of passages (101), each of the plurality of supply openings (103) having an edge region (107) with at least a part thereof bent on at least the distribution passage side facing a respective one of the plurality of distribution passages (105).

2. The bipolar plate (100) according to claim 1, characterized in that all the distribution passages (105) have the same length.

3. The bipolar plate (100) according to claim 1 or 2, characterized in that each of the respective supply openings (103) is adjacent to a respective one of the distribution passages (105) on the distribution passage side of the respective supply opening, and each of the respective distribution passages (105) extends from the respective supply opening (103) to the respective passage (101).

4. The bipolar plate (100) according to any one of claims 1 to 3, characterized in that each of the respective distribution passages (105) extends at least partially obliquely between the distribution passage side and a respective one of the passages (101).

5. The bipolar plate (100) according to claim 4, characterized in that the angle between each of the respective distribution passages (105) and the vertical axis (109) of the bipolar plate (100) is different from the angle between another distribution passage (105) and the vertical axis (109).

6. The bipolar plate (100) according to any one of claims 1 to 5, characterized in that the distribution passages (105) and the passages (101) are made of different materials.

7. The bipolar plate (100) according to claim 6, characterized in that the distribution passages (105) are made of plastic and the passages (101) are made of metal.

8. The bipolar plate (100) according to any one of claims 1 to 7, characterized in that the edge region of each supply opening (103) is bent in the direction of the center of the supply opening (103).

9. The bipolar plate is characterized in that it comprises a plurality of stabilizing webs (111) including a plurality of compensation passages (117) for pressure compensation and / or flow compensation between the supply openings (103), the bipolar plate (100) according to any one of claims 1 to 8.

10. A fuel cell system (200) comprising a plurality of bipolar plates (100) according to any one of claims 1 to 9.

11. An electrolytic cell (300) comprising a plurality of bipolar plates (100) according to any one of claims 1 to 9.

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