Bipolar plate and electrolytic bath

Abstract

The utility model relates to the technical field of bipolar plates for electrolytic baths, in particular to a bipolar plate and an electrolytic bath, comprising: a first plate body, the two side surfaces of which are respectively provided with a first flow field a and a first flow field b, the first flow field b being used for the flow of raw material water; a second flow field a and a second flow field b are arranged on the two side faces of the second plate body respectively, and the second flow field b is used for flowing of hydrogen; wherein the first plate body and the second plate body are folded and connected; the first flow field a and the second flow field a are matched to form a third flow field, and the third flow field is used for flowing of cooling liquid. Effective temperature control is achieved through three fields and two plates, water management is improved, and the service life of the system is prolonged.

Description

Technical Field

[0001] The present application relates to the technical field of bipolar plates for electrolytic cells, and in particular to a bipolar plate and an electrolytic cell. Background Art

[0002] As a key water electrolysis technology, PEM (proton exchange membrane) electrolyzer is widely used in green hydrogen production due to its low operating temperature, rapid response and high hydrogen production efficiency.

[0003] The bipolar plate is one of the main components of the PEM electrolyzer. The bipolar plate plays a good role in conducting electricity and water in the process of electrolyzing water to produce hydrogen and oxygen. When the raw water passes through the bipolar plate, direct current is used to electrolyze the raw water into hydrogen and oxygen, completing the electrolysis of hydrogen and oxygen.

[0004] The existing bipolar plates have flow channels cut into the plate body, such as the Chinese patent document with publication number CN218345555U. This metal bipolar plate can be used as a bipolar plate for electrolyzers. The correct flow channel depth and smooth flow channel shape obtained after various technical tests are cut into itself to improve the conductivity and heat dissipation performance, reduce the voltage, and after the heat dissipation is enhanced, the energy consumption is reduced, and the hydrogen production cost is reduced. However, in actual use, the heat dissipation effect of the bipolar plate still cannot reach the ideal state, and the temperature control effect is not as expected. Therefore, it is urgent to design a bipolar plate with better temperature control. Summary of the invention

[0005] The purpose of this application is to solve the defect of poor temperature control of existing bipolar plates, design bipolar plates with better temperature control, improve water management, and thus extend system life and improve stack efficiency. Based on this, this application provides a bipolar plate and electrolytic cell.

[0006] The present application provides a bipolar plate, comprising:

[0007] The first plate body has a first flow field a and a first flow field b on both sides, wherein the first flow field b is used for the flow of raw water;

[0008] The second plate body has a second flow field a and a second flow field b on two sides thereof, wherein the second flow field b is used for the flow of hydrogen;

[0009] The first plate body and the second plate body are closed and connected; the first flow field a and the second flow field a cooperate to form a third flow field, and the third flow field is used for the flow of cooling liquid.

[0010] In the above technical solution, the first plate body and the second plate body are sandwiched to form a three-field two-plate bipolar plate, and the third flow field between the first plate body and the second plate body is used for cooling, which can improve the temperature control ability of the bipolar plate and improve the cooling efficiency, thereby achieving an improvement in the temperature uniformity of the entire battery stack.

[0011] As a preferred embodiment of the present invention, the flow directions of the first flow field a and the second flow field a are different.

[0012] As a preferred embodiment of the present invention, the flow directions of the first flow field a and the second flow field a are perpendicular to each other.

[0013] In the above technical solution, the flow directions of the first flow field a and the second flow field a are set to be different. Compared with the same flow direction, this setting can effectively improve the structural strength of the bipolar plate and avoid deformation of the bipolar plate.

[0014] As a preferred embodiment of the present invention, the flow directions of the first flow field a and the first flow field b are consistent.

[0015] As a preferred embodiment of the present invention, the flow directions of the second flow field a and the second flow field b are consistent.

[0016] As a preferred embodiment of the present invention, the first flow field a, the first flow field b, the second flow field a, and the second flow field b are formed by stamping.

[0017] As a preferred embodiment of the present invention, the first plate body and the second plate body are provided with a raw water inlet, a raw water outlet, a cooling water inlet, a cooling water outlet, and a hydrogen outlet corresponding to each other.

[0018] As a preferred embodiment of the present invention, the first plate body and the second plate body are connected by laser welding.

[0019] The utility model also provides an electrolytic cell using the bipolar plate described above.

[0020] Compared with the prior art, this application has the following beneficial effects:

[0021] Effective temperature control is achieved through three fields and two plates, which improves water management and extends system life. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the first plate body in the embodiment of the utility model.

[0023] Figure 2 It is a schematic diagram of the second plate body in the embodiment of the utility model.

[0024] Figure 3 It is a schematic diagram of an explosion of a bipolar plate in an embodiment of the utility model.

[0025] Figure 4 This is a schematic diagram of a third flow field in an embodiment of the present utility model.

[0026] Figure 5 This is a schematic diagram of a third flow field in an embodiment of the present utility model.

[0027] Description of reference numerals:

[0028] 1. First plate body; 11. First flow field a; 12. First flow field b; 2. Second plate body; 21. Second flow field a; 22. Second flow field b; 23. Ridge; 3. Third flow field; 4. Raw water inlet; 5. Raw water outlet; 6. Cooling water inlet; 7. Cooling water outlet; 8. Hydrogen outlet. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] The existing bipolar plates have flow channels cut on both sides of the plate body, but the heat dissipation effect still cannot reach the ideal state, and the temperature control effect is not as expected. Therefore, it is urgent to design a bipolar plate with better temperature control effect.

[0031] Based on the above research, a bipolar plate of the present application will be specifically described below in combination with a specific implementation method.

[0032] Reference Figures 1 to 5 As shown, the bipolar plate of the present application is composed of the first plate body 1 and the second plate body 2 each having a flow field. A new flow field for cooling is formed between the first plate body 1 and the second plate body 2, forming a two-plate three-field structure to improve the heat dissipation effect.

[0033] Reference Figure 1 As shown, the first flow field a11 and the first flow field b12 are respectively arranged on the two sides of the first plate body 1, and the first flow field b12 is used for the flow of raw water. The width, depth and flow direction of the flow channel of the first flow field a11 and the first flow field b12 can be the same or different.

[0034] Reference Figure 2 As shown, the second plate 2 has a second flow field a21 and a second flow field b22 on both sides, and the second flow field b22 is used for the flow of hydrogen. The width, depth and flow direction of the flow channels of the second flow field a21 and the second flow field b22 can be the same or different.

[0035] Reference Figure 3As shown, the first plate body 1 has the same outer contour as the second plate body 2. The first plate body 1 and the second plate body 2 are closed and connected to form the bipolar plate of the present application. The gap between the first plate body 1 and the second plate body 2 forms the third flow field 3, and the third flow field 3 is not interconnected with the first flow field b12 and the second flow field a21. The third flow field 3 is used for the flow of cooling liquid. Specifically, the first flow field a11 side of the first plate body 1 is connected to the second flow field a21 side of the second plate body 2, and the first flow field a11 and the second flow field a21 form the third flow field 3.

[0036] In actual use, the first flow field b12 of the first plate body 1 is used for the flow of raw water, the second flow field b22 of the second plate body 2 is used for the flow of hydrogen, and the coolant cools the entire bipolar plate through the third flow field 3.

[0037] In some possible embodiments, the flow directions of the first flow field a11 and the second flow field a21 are different. Preferably, the flow directions of the first flow field a11 and the second flow field a21 are perpendicular to each other. The flow channels of the first flow field a11 and the second flow field a21 are designed to face different directions. Compared with the same flow direction, this design can effectively improve the structural strength of the bipolar plate and avoid deformation of the bipolar plate.

[0038] When the flow directions of the first flow field a11 and the second flow field a21 are different, the third flow field 3 is formed by two flow channels in different directions. Figure 4 As shown in the figure, the third flow field 3 is composed of the flow channel of the first flow field a11 and the ridge 23 of the second flow field a21. Figure 5 As shown, the third flow field 3 is composed of the flow channel of the first flow field a11 and the flow channel of the second flow field a21. Along the flow direction of the third flow field 3, the cross-sectional area of ​​the flow channel changes continuously. This design can effectively reduce the flow velocity of the coolant, so that the coolant can fully contact the bipolar plate, and further improve the temperature uniformity of the bipolar plate.

[0039] In some possible embodiments, the flow direction of the first flow field a11 is consistent with that of the first flow field b12.

[0040] In some possible embodiments, the flow directions of the second flow field a21 and the second flow field b22 are consistent.

[0041] In some possible embodiments, the first flow field a11, the first flow field b12, the second flow field a21, and the second flow field b22 are formed by stamping. The first plate body 1 and the second plate body 2 are formed into double-sided flow fields by stamping, and the molding is convenient and fast.

[0042] In some possible embodiments, the first plate body 1 and the second plate body 2 are provided with a raw water inlet 4, a raw water outlet 5, a cooling water inlet 6, a cooling water outlet 7, and a hydrogen outlet 8 in one-to-one correspondence. The raw water inlet 4 and the raw water outlet 5 are connected to the first flow field a11, and the flow direction of the first flow field a11 is from the raw water inlet 4 to the raw water outlet 5. The cooling water inlet 6 and the cooling water outlet 7 are connected to the third flow field 3. The hydrogen outlet 8 is connected to the second flow field a21.

[0043] In some possible embodiments, the first plate body 1 and the second plate body 2 are connected by laser welding.

[0044] An electrolytic cell, using the bipolar plate described above, can improve cooling efficiency and achieve effective temperature control.

[0045] The advantages of this application are:

[0046] 1. Effective temperature control:

[0047] Improved cooling efficiency: The cooling water flowing in the middle of the bipolar plate can more evenly absorb the heat generated by the fuel cell reaction and avoid local overheating. This is especially important for PEM electrolyzers, because PEM electrolyzers are very sensitive to temperature changes, and excessively high temperatures may cause the membrane to dry out or be damaged.

[0048] Uniform temperature distribution: This design helps achieve temperature uniformity throughout the battery stack, avoiding performance fluctuations due to uneven temperature.

[0049] 2. Water management improvements:

[0050] PEM electrolyzers generate water during the electrochemical reaction, and water management is critical to maintaining membrane wetness. Circulation of intercooling water between bipolar plates may help better manage membrane hydration and prevent over-drying or over-watering.

[0051] Simplified water management: Due to the separation of cooling water and feed water, the amount and hydration state of water entering the electrolyzer can be controlled more accurately, reducing the risk of membrane drying or water accumulation.

[0052] 3. Extended system life:

[0053] Reduction of mechanical stress: The presence of cooling water can help reduce the mechanical stress caused by thermal expansion, thereby extending the life of the electrolyzer.

[0054] Balanced cell performance: Uniform control of temperature and humidity helps all cells in the cell maintain consistent performance and reduce local degradation.

[0055] Improve battery efficiency:

[0056] Optimizing the reaction environment: By precisely controlling temperature and humidity, the working environment of the electrolyzer is more optimized, thereby improving the efficiency of the electrochemical reaction.

[0057] Reduced byproduct impact: Better cooling and water management can reduce the negative impact of byproducts (such as hydrogen and oxygen evolution on the plates) on electrolyzer performance.

[0058] Improve system design flexibility:

[0059] Modular design: This design can allow for a more flexible modular layout to accommodate different power requirements and application scenarios, especially in electrolyzer systems that require a high degree of customization.

[0060] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A bipolar plate, characterized in that: include: The first plate body has a first flow field a and a first flow field b on both sides, wherein the first flow field b is used for the flow of raw water; The second plate body has a second flow field a and a second flow field b on two sides thereof, wherein the second flow field b is used for the flow of hydrogen; The first plate body and the second plate body are closed and connected; the first flow field a and the second flow field a cooperate to form a third flow field, and the third flow field is used for the flow of cooling liquid.

2. A bipolar plate according to claim 1, characterized in that: The first flow field a and the second flow field a have different flow directions.

3. A bipolar plate according to claim 2, characterized in that: The flow directions of the first flow field a and the second flow field a are perpendicular to each other.

4. A bipolar plate according to claim 1, characterized in that: The flow directions of the first flow field a and the first flow field b are consistent.

5. A bipolar plate according to claim 1, characterized in that: The flow directions of the second flow field a and the second flow field b are consistent.

6. A bipolar plate according to claim 1, characterized in that: The first flow field a, the first flow field b, the second flow field a, and the second flow field b are formed by stamping.

7. A bipolar plate according to claim 1, characterized in that: The first plate body and the second plate body are provided with a raw water inlet, a raw water outlet, a cooling water inlet, a cooling water outlet, and a hydrogen outlet corresponding to each other.

8. A bipolar plate according to claim 1, characterized in that: The first plate body and the second plate body are connected by laser welding.

9. An electrolytic cell, characterized in that: Use the bipolar plate according to any one of claims 1 to 8.

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