Bipolar plate, fuel cell system and electrolysis device

Abstract

The invention relates to a bipolar plate (100) for a chemical energy converter (200, 300). The bipolar plate (100) comprises:-a plurality of channels (101) for conducting an operating medium of the energy converter (200, 300),-a plurality of supply openings (103) for supplying the plurality of channels (101) with an operating medium,-a plurality of distribution channels (105) for distributing the operating medium onto the plurality of channels (101), each distribution channel (105) of the plurality of distribution channels (105) extends between a corresponding supply opening (103) of the plurality of supply openings (103) and a corresponding channel (101) of the plurality of channels (101), and wherein the distribution channels (105) of the plurality of distribution channels (105) extend between the corresponding supply opening (103) of the plurality of supply openings (103) and the corresponding channel (101) of the plurality of channels (101). Each supply opening (103) of the plurality of supply openings (103) has an at least partially curved edge region at least on a distribution channel side facing a corresponding distribution channel (105) of the plurality of distribution channels (105).

Description

Technical Field

[0001] The invention relates to a bipolar plate, a fuel cell system and an electrolysis device. Background Art

[0002] In cells of energy converters, such as electrolysis devices or fuel cell systems, the individual operating media, such as reactants, must be evenly distributed over the reaction surfaces of the corresponding cells in order to achieve an optimal efficiency of the energy converter. In order to distribute the operating media provided via supply openings, so-called "ports", over the reaction surfaces, distribution channels are used, which are usually arranged in distribution areas.

[0003] Supply openings that are the same size as the distribution area usually result in a mechanically weaker bipolar plate, so that such supply openings must be reinforced by means of webs. However, such webs have a detrimental effect on the volume flow out of the corresponding supply opening. Summary of the invention

[0004] Within the framework of the present invention, a bipolar plate, a fuel cell system and an electrolysis device are proposed. Further features and details of the invention are derived from the respective dependent claims, the description and the drawings. The features and details described in conjunction with the bipolar plate according to the invention naturally also apply to the fuel cell system according to the invention or the electrolysis device according to the invention, and vice versa, so that the disclosures concerning the various aspects of the invention are always mutually referenced or mutually referenceable.

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

[0006] Therefore, according to a first aspect of the present invention, a bipolar plate for a chemical energy converter, such as a fuel cell or an electrolysis device, is proposed.

[0007] The proposed bipolar plate comprises a plurality of channels for guiding an operating medium of an energy converter, a plurality of supply openings for supplying the plurality of channels with the operating medium, and a plurality of supply openings for distributing the operating medium provided through the plurality of supply openings to the plurality of channels, wherein each of the plurality of distribution channels extends between a corresponding supply opening in the plurality of supply openings and a corresponding channel in the plurality of channels, respectively, and each of the plurality of supply openings has an at least partially curved edge region at least on a distribution channel side facing a corresponding distribution channel in the plurality of distribution channels.

[0008] In the context of the present invention, supply openings are understood to be so-called “ports” which, during operation, supply the bipolar plate with an operating medium, for example fuel or water.

[0009] In the context of the present invention, a distribution channel is understood to be a flow guide device that guides the operating medium flowing out of the supply opening to the corresponding channel or the reaction zone of the bipolar plate. A distribution channel can be formed integrally from a channel or as an independent unit, in particular from a material different from the corresponding channel of the bipolar plate. Of course, the distribution channel can also be composed of the same material as, for example, the corresponding channel of the bipolar plate.

[0010] The invention is based on the principle that each of the plurality of supply openings has a curved edge region at least on that distribution channel side which faces the corresponding distribution channel of the plurality of distribution channels.

[0011] The curved edge regions of the supply channels of the proposed bipolar plate make it possible to arrange the distribution channels in such a way that they are uniformly supplied with operating medium even if they run around corresponding webs for stabilizing the bipolar plate. Accordingly, so-called “flow shadows”, i.e. negative influences on the flow behavior of the operating medium flowing out of the distribution openings, are prevented or reduced.

[0012] Furthermore, the curved edge region of the supply channel enables particularly advantageous flow dynamics in the distribution area with a particularly compact distribution area geometry.

[0013] It can be provided that all distribution channels have the same length. Due to the distribution channels of the same length, it can be ensured that the channels of the proposed bipolar plate are evenly supplied by the distribution channels. In this case, the curved edge region of the supply opening makes it possible that the distribution channels can have the same length and run around the corresponding stabilizing web.

[0014] Furthermore, it can be provided that the respective supply openings adjoin the corresponding distribution channel with their distribution channel side and that the respective distribution channel extends from the respective supply opening to the corresponding channel.

[0015] By aligning the curved distribution channel sides of each supply opening with the corresponding distribution channel, due to the curvature of the edge area of ​​the supply opening, additional space or additional surface will be provided compared to a straight edge area, and the distribution channel can extend in the space or the surface.

[0016] Furthermore, it can be provided that the individual distribution channels each run at least partially obliquely between the distribution channel side and the associated channel.

[0017] By means of obliquely extending distribution channels, i.e. distribution channels extending at an acute angle or an angle of less than 90°, for example, relative to the vertical axis of the bipolar plate, it is possible that the individual distribution channels can be routed around the stabilizing webs in the edge region of the stabilizing webs or around the stabilizing webs, so that the influence of the stabilizing webs on the flow behavior of the medium flowing through the distribution channels is reduced. In this case, the vertical axis can extend, for example, parallel to the long side of the bipolar plate.

[0018] The plurality of distribution channels provided according to the invention can of course include straight distribution channels, i.e. distribution channels extending parallel to the vertical axis, and oblique distribution channels. In particular, the individual distribution channels adjacent to the stabilizing web can extend obliquely, while the individual distribution channels arranged in the middle region of the corresponding distribution area can extend straight.

[0019] Furthermore, it can be provided 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 different angles with respect to the vertical axis of the proposed bipolar plate, i.e. with a specific inclination or tilt of the distribution channels, the inclination of the distribution channels can be coordinated with the radius of curvature of the corresponding distribution openings, so that, regardless of the inclination of the individual distribution channels, all distribution channels conduct the same or comparable volume flow of the operating medium to the channels of the proposed bipolar plate. In addition, it can be provided that the distribution channels and the channels are composed of different materials.

[0021] Furthermore, it can be provided that the distribution channel consists of plastic and the channel consists of metal.

[0022] In order to ensure that the distribution channels provided according to the invention are precisely formed according to a predetermined arrangement, the distribution channels can be formed from a particularly easy to shape material, such as plastic. Accordingly, the distribution channels can be introduced preconfigured in the form of distribution zones into the base body of the proposed bipolar plate, which is composed of metal, for example.

[0023] Furthermore, it can be provided that the edge region of the individual supply openings is curved 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 surface available for the distribution channels running between the edge region and the individual channels of the proposed bipolar plate is maximized.

[0025] Furthermore, it can be provided that the bipolar plate comprises a plurality of stabilizing webs, which in particular comprise a plurality of equalizing channels for pressure equalization and / or flow equalization between the supply openings.

[0026] The stabilizing webs maximize the mechanical load-bearing capacity of the bipolar plate. By integrating the compensating channels in the stabilizing webs, a uniform distribution of the pressure and / or flow forces is achieved between the individual regions of the bipolar plate separated by the stabilizing webs.

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

[0028] According to a third aspect, the invention relates to an electrolysis device having the proposed possible configuration of a bipolar plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Further advantages, features and details of the invention are apparent from the following description, in which embodiments of the invention are described in detail with reference to the accompanying drawings. The features mentioned in the claims and in the description are essential to the invention individually or in any combination. The drawings show:

[0030] Figure 1 : Schematic description of possible configurations of the proposed bipolar plate;

[0031] Figure 2 : Possible configurations of the proposed fuel cell system;

[0032] Figure 3 : Possible configuration of the proposed electrolysis device. DETAILED DESCRIPTION

[0033] exist Figure 1 A bipolar plate 100 for use in an energy converter, such as a fuel cell system or an electrolyzer, is described.

[0034] The bipolar plate 100 comprises a plurality of channels 101 for conducting an operating medium of the energy converter. For example, the channels 101 form a reaction zone or a reaction area of ​​the bipolar plate 100 .

[0035] Furthermore, the bipolar plate 100 comprises a plurality of supply openings 103 for supplying the channels 101 with a plurality of operating media or an operating medium, and a plurality of distribution channels 105 which extend between the supply openings 103 and the channels 101 .

[0036] The supply opening 103 is bent in an edge region 107 on the distribution channel side facing the distribution channel 105 .

[0037] In addition Figure 1 It can be clearly seen in FIG that several of the distribution channels 105 run obliquely with respect to the vertical axis 109 . In this case, all distribution channels 105 have the same length and run around the stabilizing web 111 .

[0038] Optionally, the stabilizing web 111 may comprise a balancing channel 117 which enables a pressure balance and a flow balance between the supply openings 103 .

[0039] The distribution area 113 includes straight distribution channels 105 running parallel to the vertical axis 109 only in the central area and oblique distribution channels 105 in other areas, while in the distribution area 115, oblique distribution channels 105 are arranged only in the outer edge areas and straight distribution channels 105 are arranged in other areas.

[0040] Due to the geometry of the distribution openings 103 and the distribution channels 105 , the channel 101 is supplied uniformly with operating medium.

[0041] exist Figure 2 The fuel cell system 200 is described in FIG. The fuel cell system 200 includes a Figure 1 A fuel cell stack 201 having multiple bipolar plates 100 as described in FIG.

[0042] exist Figure 3 The electrolysis device 300 is described in FIG. The electrolysis device 300 includes a Figure 1 A battery stack 301 of multiple bipolar plates 100 described in FIG.

Claims

1. A bipolar plate (100) for a chemical energy converter (200, 300), wherein: The bipolar plate (100) comprises: - a plurality of channels (101) for conducting an operating medium of the energy converter (200, 300), a plurality of supply openings (103) for supplying the plurality of channels (101) with operating medium, - a plurality of distribution channels (105) for distributing the operating medium to the plurality of channels (101), wherein each distribution channel (105) of the plurality of distribution channels (105) extends between a corresponding supply opening (103) of the plurality of supply openings (103) and a corresponding channel (101) of the plurality of channels (101), respectively; and Wherein, each supply opening (103) among the plurality of supply openings (103) has an at least partially curved edge region (107) at least on the distribution channel side facing the corresponding distribution channel (105) among the plurality of distribution channels (105).

2. The bipolar plate (100) according to the preceding claim, characterized in that All distribution channels (105) have the same length.

3. The bipolar plate (100) according to claim 1 or 2, characterized in that: Each supply opening (103) adjoins the corresponding distribution channel (105) with its distribution channel side, and each distribution channel (105) extends from the corresponding supply opening (103) to the corresponding channel (101).

4. The bipolar plate (100) according to any one of the preceding claims, characterized in that Each distribution channel (105) runs at least partially obliquely between the distribution channel side and the corresponding channel (101).

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

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

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

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

9. The bipolar plate (100) according to any one of the preceding claims, characterized in that The bipolar plate comprises a plurality of stabilizing webs (111), which in particular comprise a plurality of balancing channels (117) for pressure balancing and / or flow balancing between the supply openings (103).

10. A fuel cell system (200), wherein: The fuel cell system (200) comprises a plurality of bipolar plates (100) according to any one of claims 1 to 9.

11. An electrolysis device (300), wherein: The electrolysis device (300) comprises a plurality of bipolar plates (100) according to any one of claims 1 to 9.

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