A bipolar plate for a press-formed electrolytic cell

Abstract

The utility model provides a kind of bipolar plate for stamping forming electrolytic cell, including bipolar plate anode surface and bipolar plate cathode surface;Anode active area and the anode first distribution area and the anode second distribution area located in its two sides are provided on bipolar plate anode surface;Cathode active area and the cathode first distribution area and the cathode second distribution area located in its two sides are provided on bipolar plate cathode surface;Water inlet / outlet and second hydrogen outlet are provided on the outside of anode and cathode first distribution area, and water outlet / water inlet and first hydrogen outlet are provided on the outside of anode and cathode second distribution area;The outside of anode and cathode first distribution area forms protrusion, and the end of protrusion is between water inlet and second hydrogen outlet;The outside of anode and cathode second distribution area forms protrusion, and the end of protrusion is between water outlet and first hydrogen outlet.The bipolar plate of the utility model is better to membrane electrode support effect under back pressure, and can reduce the invasion of membrane electrode to distribution area.

Description

Technical Field

[0001] This utility model belongs to the field of PEM electrolysis water production hydrogen technology, specifically relating to a bipolar plate for a stamped electrolytic cell. Background Technology

[0002] Proton exchange membrane (PEM) water electrolysis for hydrogen production has become a key area for future development due to its compact structure, high efficiency, strong adaptability, high hydrogen purity, wide operating range, and environmental friendliness.

[0003] The PEM electrolyzer is a highly efficient hydrogen production device, mainly composed of several electrolysis chambers connected in series. Each electrolysis chamber is primarily composed of bipolar plates, cathode seals, cathode gas diffusion layers, membrane electrodes, anode gas diffusion layers, and anode seals stacked sequentially.

[0004] As a key component of the electrolyzer, the bipolar plate primarily serves to provide electrical connections, separate adjacent electrolysis chambers, distribute fluids, transfer mass, manage heat, and provide mechanical support. The bipolar plate has an anode side and a cathode side, each typically equipped with corresponding flow channels to regulate the two-phase flow distribution within the electrolysis chamber. The anode side mainly handles the transport of reactant water and the reaction product oxygen, requiring the uniform distribution of reactant water and the rapid removal of unreacted water and the reaction product oxygen. The cathode side primarily handles permeated water and the reaction product hydrogen, which must be rapidly removed.

[0005] Existing bipolar plates have a single-plate, two-electrode design (one side of the bipolar plate serves as the anode and the other as the cathode, and the bipolar plate consists of only one component). For example, bipolar plates using etching processes are used. However, in the field of stamped bipolar plates, the single-plate, two-electrode design often employs a lattice distribution area structure or an independent distribution area structure (using additional porous materials as distribution areas, such as titanium mesh or titanium plate components).

[0006] Independent distribution area structure: Additional parts need to be added to the anode distribution area and cathode distribution area of ​​the bipolar plate. The additional parts are difficult to connect with the stamped bipolar plate itself, and are generally connected by welding, which makes the assembly process more complicated.

[0007] Lattice Structure: In stamping processes, the shape and size of the forming features of parts are limited by the process. If a lattice structure is used, forward and reverse stamping must be performed in the same area to ensure the uniformity of fluid distribution and thus form the flow fields of the distribution zones on both the cathode and anode sides. However, using a lattice structure will result in a relatively large span between adjacent features, which leads to poor support for the membrane electrode under back pressure. This causes the membrane electrode to intrude into the flow field of the distribution zone, affecting the function of the distribution zone and resulting in uneven fluid distribution in the active zone. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a bipolar plate for stamped electrolytic cells. This invention utilizes the forming characteristics of the stamping process to construct a staggered flow field with varying elevations in the bipolar plate distribution area. By leveraging the Z-axis space created by these elevation differences, the flow fields of the anode and cathode distribution areas are simultaneously constructed in the same region, ensuring uniform distribution of reactants on the anode surface while allowing for rapid gas discharge from the cathode surface. Furthermore, this structure provides better support for the membrane electrode under back pressure, reducing the intrusion of the membrane electrode into the distribution area.

[0009] To achieve the above technical objectives, the technical solution adopted in this utility model embodiment is as follows:

[0010] A bipolar plate for a stamped electrolytic cell includes an anode surface and a cathode surface of the bipolar plate arranged opposite to each other in the thickness direction.

[0011] The bipolar plate anode surface is provided with an anode active region and an anode first distribution region and an anode second distribution region located on both sides of the anode active region;

[0012] The cathode surface of the bipolar plate is provided with a cathode active region and a first cathode distribution region and a second cathode distribution region located on both sides of the cathode active region.

[0013] The outer sides of the first anode distribution area and the first cathode distribution area are each provided with a water inlet / outlet and a second hydrogen outlet. The outer sides of the second anode distribution area and the second cathode distribution area are each provided with a water outlet / inlet and a first hydrogen outlet.

[0014] A protrusion is formed on the outer side of the first anode distribution area and the first cathode distribution area, and the end of the protrusion is located between the water inlet and the second hydrogen outlet.

[0015] A protrusion is formed on the outer side of the second anode distribution area and the second cathode distribution area, and the end of the protrusion is located between the water outlet and the first hydrogen outlet.

[0016] Furthermore, the anode first distribution area, cathode first distribution area, anode second distribution area and cathode second distribution area all have distribution area ridges and distribution area backwash portions arranged alternately, and the height h2 of the distribution area ridge is greater than the height h1 of the distribution area backwash portion.

[0017] Furthermore, the height h2 of the distribution area ridge and the height h1 of the distribution area recoil portion satisfy the following condition: h1 = (0.2~0.8) * h2.

[0018] Furthermore, the Z-direction space formed by the height difference between the distribution zone ridge and the distribution zone backflush section serves as the distribution zone flow channel on the anode surface of the bipolar plate, and the flow channel is used to uniformly distribute the reactant water to the anode active zone.

[0019] The Z-direction space formed by the backwash section of the distribution area serves as the distribution area flow channel on the cathode surface of the bipolar plate. The flow channel is used to quickly discharge the water that has permeated from the anode of the bipolar plate to the cathode and the reaction product hydrogen gas.

[0020] Furthermore, a first CVM and a second CVM are provided on the side of the bipolar plate, the first CVM being located at a corner near the second hydrogen outlet, and the second CVM being located at a corner near the first hydrogen outlet.

[0021] Furthermore, the anode active region is provided with an anode flow channel, and the cathode active region is provided with a cathode flow channel. The anode flow channel and the cathode flow channel are integrally formed and arranged at intervals, with a period of a for both.

[0022] Furthermore, the anode flow channel and the cathode flow channel are wavy, and two adjacent bipolar plates are stacked by rotating 180° in the plane, and the anode flow channel of the anode active region and the cathode flow channel of the cathode active region are arranged in a twisted pattern.

[0023] Furthermore, the bipolar plate is stamped to form an anode surface on one side of the plate and a cathode surface on the other side.

[0024] The anode first distribution area, cathode first distribution area, anode second distribution area, cathode second distribution area, anode active area, and cathode active area are integrally formed.

[0025] The beneficial effects of the technical solution provided by this utility model embodiment are:

[0026] 1. The electrolytic cell of this utility model is formed by stamping bipolar plates, and the anode and cathode distribution area and flow field area are integrally formed. Flow field structures are formed on the anode side and cathode side respectively, which can simplify the assembly process of PEM electrolytic cell, reduce the types of parts in the assembly process, and the bipolar plates have no distinction between cathode plates and anode plates. The parts are uniform and there is no problem of mixing materials, which can improve the assembly efficiency.

[0027] 2. The bipolar plate distribution area of ​​the stamped electrolytic cell of this utility model has an interlaced structure, which has high structural strength and smaller span. Under back pressure, it provides better support for the membrane electrode and can improve the support effect of the distribution area on the membrane electrode, and reduce the intrusion of the membrane electrode into the distribution area.

[0028] 3. The bipolar plate distribution area of ​​the stamped electrolytic cell of this utility model has a height difference. Based on the characteristics of the stamping process, the Z-direction space (perpendicular to the plate surface) formed by the height difference is used to form the flow field of the anode and cathode distribution area, which can make the reaction water on the anode surface uniformly distributed and the gas on the cathode surface quickly discharged. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the anode surface of the bipolar plate in an embodiment of this utility model.

[0030] Figure 2 for Figure 1 A partial structural diagram of the first distribution region I of the anode on the anode surface of the bipolar plate.

[0031] Figure 3 for Figure 2 A schematic diagram of the cross-sectional structure of the first distribution zone.

[0032] Figure 4 This is a schematic diagram of the structure of the cathode surface of the bipolar plate in an embodiment of this utility model.

[0033] Figure 5 This is a schematic diagram of the flow channel cross-section of the active region of the bipolar plate in an embodiment of this utility model.

[0034] Explanation of reference numerals in the attached figures: 1—Bipolar plate anode surface; 2—Anode active region; 3—Anode first distribution region; 4—Anode second distribution region; 5—Water inlet; 6—Water outlet; 7—First hydrogen outlet; 8—Second hydrogen outlet; 9—First CVM; 10—Second CVM; 11—Bipolar plate cathode surface; 12—Cathode active region; 13—Cathode first distribution region; 14—Cathode second distribution region; 15—Distribution region ridge; 16—Distribution region backflushing section; 17—Anode flow channel; 18—Cathode flow channel; h1—Height of distribution region backflushing section; h2—Height of distribution region ridge; a—Active region flow channel period. Detailed Implementation

[0035] In the description of this utility model, it should be understood that the directional terms such as "inner" and "outer", "upper" and "lower", "left" and "right" indicate the orientation or positional relationship, which are usually based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this utility model.

[0036] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0037] Example 1

[0038] like Figure 1 and 4 As shown, a bipolar plate for a stamped electrolytic cell includes a bipolar plate anode surface 1 and a bipolar plate cathode surface 11 that are opposite each other in the thickness direction.

[0039] An anode active region 2 and a first anode distribution region 3 and a second anode distribution region 4 located on both sides of the anode active region 2 are provided on the anode surface 1 of the bipolar plate. An inlet 5 and a second hydrogen outlet 8 are provided on the outer side of the first anode distribution region 3, and an outlet 6 and a first hydrogen outlet 7 are provided on the outer side of the second anode distribution region 4.

[0040] The cathode surface 11 of the bipolar plate is provided with a cathode active area 12 and a cathode first distribution area 13 and a cathode second distribution area 14 located on both sides of the cathode active area 12. A water inlet 5 and a second hydrogen outlet 8 are provided on the outer side of the cathode first distribution area 13, and a water outlet 6 and a first hydrogen outlet 7 are provided on the outer side of the cathode second distribution area 14.

[0041] A protrusion is formed on the outer side of the first anode distribution zone 3, with the end of the protrusion located between the inlet 5 and the second hydrogen outlet 8; a protrusion is formed on the outer side of the second anode distribution zone 4, with the end of the protrusion located between the outlet 6 and the first hydrogen outlet 7.

[0042] A protrusion is formed on the outer side of the first distribution area 13 of the cathode, and the end of the protrusion is located between the water inlet 5 and the second hydrogen outlet 8; a protrusion is formed on the outer side of the second distribution area 14 of the cathode, and the end of the protrusion is located between the water outlet 6 and the first hydrogen outlet 7.

[0043] like Figure 2 and 3 As shown, the anode first distribution region 3, the cathode first distribution region 13, the anode second distribution region 4 and the cathode second distribution region 14 all have staggered distribution region ridges 15 and distribution region backflush parts 16 with small spans, which can provide better support for the membrane electrode under back pressure and reduce the intrusion of the membrane electrode into the distribution region under back pressure; the height h2 of the distribution region ridge 15 is greater than the height h1 of the distribution region backflush part 16.

[0044] Preferably, the height h2 of the distribution zone ridge 15 and the height h1 of the distribution zone recoil portion 16 satisfy the following condition: h1 = (0.2~0.8) * h2.

[0045] The Z-direction space formed by the height difference between the distribution zone ridge 15 and the distribution zone backflush section 16 serves as the distribution zone flow channel of the bipolar plate anode surface 1, which is used to uniformly distribute the reactant water to the anode active zone 2.

[0046] The Z-direction space formed by the backwash section 16 of the distribution area serves as the distribution area flow channel of the bipolar cathode surface 11, which is used to quickly discharge the water and reaction product hydrogen that have permeated from the bipolar anode to the bipolar cathode.

[0047] A first CVM 9 and a second CVM 10 are disposed on the side of the bipolar plate. The first CVM 9 is located at the corner near the second hydrogen outlet 8, and the second CVM 10 is located at the corner near the first hydrogen outlet 7. CVM stands for Cell Voltage Monitor.

[0048] like Figure 5 As shown, the anode active region 2 is provided with an anode flow channel 17, and the cathode active region 12 is provided with a cathode flow channel 18. The anode flow channel 17 and the cathode flow channel 18 are integrally formed and arranged at intervals, with a flow channel period of a.

[0049] The anode channel 17 and the cathode channel 18 are wavy, and the wavy trajectory is either a sine wave or a non-sine wave. The undulation of the waves increases the turbulence, which helps the flow of the reacting water and prevents the reacting water from accumulating in a corner.

[0050] The two adjacent bipolar plates are stacked by rotating 180° in the plane, and the anode flow channel 17 of the anode active region 2 and the cathode flow channel 18 of the cathode active region 12 are arranged in a twisted pattern, which improves the overall support of the bipolar plates.

[0051] The bipolar plate is formed by stamping, and the anode first distribution area 3, cathode first distribution area 13, anode second distribution area 4, cathode second distribution area 14, anode active area 2 and cathode active area 12 are integrally formed.

[0052] The reaction water flow process inside the bipolar plate is as follows: The reaction water enters the bipolar plate from the inlet 5, first passes through the first anode distribution zone 3, and then enters the anode active zone 2 for reaction. Subsequently, it enters the second anode distribution zone 4, and finally returns to the main channel through the outlet 6.

[0053] Finally, it should be noted that the above specific embodiments are only used to illustrate the technical solution of this utility model and not to limit it. Although this utility model has been described in detail with reference to examples, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solution of this utility model without departing from the spirit and scope of the technical solution of this utility model, and all such modifications and substitutions should be covered within the scope of the claims of this utility model.

Claims

1. A bipolar plate for a stamped electrolytic cell, characterized in that, It includes a bipolar plate anode surface (1) and a bipolar plate cathode surface (11) arranged opposite to each other in the thickness direction; The bipolar plate anode surface (1) is provided with an anode active area (2) and an anode first distribution area (3) and an anode second distribution area (4) located on both sides of the anode active area (2). The cathode surface (11) of the bipolar plate is provided with a cathode active area (12) and a cathode first distribution area (13) and a cathode second distribution area (14) located on both sides of the cathode active area (12). The outer sides of the first anode distribution area (3) and the first cathode distribution area (13) are provided with inlet (5) / outlet (6) and second hydrogen outlet (8), and the outer sides of the second anode distribution area (4) and the second cathode distribution area (14) are provided with outlet (6) / inlet (5) and first hydrogen outlet (7). A protrusion is formed on the outer side of the anode first distribution area (3) and the cathode first distribution area (13), and the end of the protrusion is located between the water inlet (5) and the second hydrogen outlet (8). A protrusion is formed on the outer side of the second anode distribution area (4) and the second cathode distribution area (14), and the end of the protrusion is located between the water outlet (6) and the first hydrogen outlet (7).

2. The bipolar plate for stamped electrolytic cells according to claim 1, characterized in that, The anode first distribution area (3), cathode first distribution area (13), anode second distribution area (4) and cathode second distribution area (14) each have staggered distribution area ridges (15) and distribution area backwash portions (16), and the height h2 of the distribution area ridge (15) is greater than the height h1 of the distribution area backwash portion (16).

3. The bipolar plate for stamped electrolytic cells according to claim 2, characterized in that, The height h2 of the distribution area ridge (15) and the height h1 of the distribution area recoil part (16) satisfy the following condition: h1 = (0.2~0.8) * h2.

4. The bipolar plate for stamped electrolytic cells according to claim 2, characterized in that, The Z-direction space formed by the height difference between the distribution zone ridge (15) and the distribution zone backwash section (16) serves as the distribution zone flow channel of the bipolar plate anode surface (1), and the flow channel is used to uniformly distribute the reactant water to the anode active zone (2). The Z-direction space formed by the backwash section (16) of the distribution area serves as the distribution area flow channel of the cathode surface (11) of the bipolar plate. The flow channel is used to quickly discharge the water and reaction product hydrogen that have permeated from the anode of the bipolar plate to the cathode.

5. The bipolar plate for stamped electrolytic cells according to claim 1, characterized in that, The bipolar plate has a first CVM (9) and a second CVM (10) on its side. The first CVM (9) is located at the corner near the second hydrogen outlet (8), and the second CVM (10) is located at the corner near the first hydrogen outlet (7).

6. The bipolar plate for stamped electrolytic cells according to claim 1, characterized in that, The anode active region (2) is provided with an anode flow channel (17), and the cathode active region (12) is provided with a cathode flow channel (18). The anode flow channel (17) and the cathode flow channel (18) are integrally formed and arranged at intervals, with a period of a.

7. The bipolar plate for stamped electrolytic cells according to claim 6, characterized in that, The anode flow channel (17) and cathode flow channel (18) are wavy. Adjacent bipolar plates are stacked by rotating 180° in the plane. The anode flow channel (17) of the anode active region (2) and the cathode flow channel (18) of the cathode active region (12) are arranged in a twisted pattern.

8. The bipolar plate for stamping electrolytic cells according to any one of claims 1-7, characterized in that, The bipolar plate is formed by stamping, with a bipolar plate anode surface (1) on one side of the plate and a bipolar plate cathode surface (11) on the other side. The anode first distribution area (3), cathode first distribution area (13), anode second distribution area (4), cathode second distribution area (14), anode active area (2) and cathode active area (12) are integrally formed.

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