阅读说明：本技术 单极板、双极板组件及制造工艺、电堆以及燃料电池车辆 (Unipolar plate, bipolar plate assembly, manufacturing process, electric pile and fuel cell vehicle ) 是由 王慧 周俊 覃博文 王手龙 欧兵兵 于 2021-07-30 设计创作，主要内容包括：本发明公开了一种单极板、双极板组件及制造工艺、电堆以及燃料电池车辆,解决现有双极板制造工艺存在生产成本高、制备周期长、产量低的技术问题,以及制备得到的双极板耐久性及密封性能较差的技术问题。单极板的密封线上设置有与流道同向凸起的密封槽,密封槽的凸起高度小于流道的凸起高度；密封槽的槽壁中设置贯通槽壁的至少一个注塑工艺孔。双极板组件包括两块由密封组件连接为一体的单极板。两块单极板通过一体成型的密封组件连接为一体,密封组件充当焊线,由此可以取消现有双极板制造工艺中的焊接步骤；并且板件密封圈与气场侧密封圈一体成型,此结构可解决现有技术中密封圈粘固失效、移位所产生的密封失效问题。(The invention discloses a unipolar plate, a bipolar plate assembly, a manufacturing process, a galvanic pile and a fuel cell vehicle, and solves the technical problems of high production cost, long preparation period and low yield of the existing bipolar plate manufacturing process and the technical problems of poor durability and sealing performance of the prepared bipolar plate. A sealing groove which protrudes in the same direction as the flow channel is arranged on the sealing line of the unipolar plate, and the protruding height of the sealing groove is smaller than that of the flow channel; at least one injection molding process hole penetrating through the groove wall is formed in the groove wall of the sealing groove. The bipolar plate assembly comprises two unipolar plates which are connected into a whole by a sealing assembly. The two unipolar plates are connected into a whole through the integrally formed sealing assembly, and the sealing assembly serves as a welding wire, so that the welding step in the existing bipolar plate manufacturing process can be eliminated; and the plate sealing ring and the gas field side sealing ring are integrally formed, so that the sealing failure problem caused by cementation failure and displacement of the sealing ring in the prior art can be solved.)

1. The utility model provides a unipolar plate, be provided with bellied runner and the seal line that is used for assembling the sealing washer on unipolar plate which characterized in that: a sealing groove which protrudes in the same direction as the flow channel is arranged on the sealing line, and the protruding height of the sealing groove is smaller than that of the flow channel; at least one injection molding process hole penetrating through the groove wall is formed in the groove wall of the sealing groove.

2. The unipolar plate of claim 1, wherein: the seal groove includes hydrogen mouth inner frame seal groove, air mouth inner frame seal groove and frame seal groove, hydrogen mouth inner frame seal groove the air mouth inner frame seal groove be provided with in the frame seal groove on at least one the technology hole of moulding plastics.

3. The unipolar plate of claim 2, wherein: the edge of the unipolar plate is provided with a raised reinforcing rib, and the raised height of the reinforcing rib is equal to that of the flow channel; the hydrogen mouth inner frame seal groove, the air mouth inner frame seal groove and the outer frame seal groove are all provided with the injection molding process hole.

4. The unipolar plate of claim 2, wherein: the edge of the unipolar plate is provided with a raised bending part, and the height of the raised bending part is smaller than that of the raised flow channel; the hydrogen port inner frame sealing groove and the air port inner frame sealing groove are both provided with the injection molding process holes.

5. The unipolar plate of any one of claims 1-4, wherein: the size of the injection molding process hole in the width direction of the sealing groove is 1/4-3/4 of the width of the groove bottom of the sealing groove; the hole pitch of the injection molding process holes is 5-50 mm; the unipolar plate is a precoated metal plate.

6. A bipolar plate assembly, comprising: comprising a seal assembly and two unipolar plates according to any one of claims 1 to 5; the two unipolar plates are attached in a posture that the flow channel openings are opposite to each other to form a negative plate and a positive plate respectively; the openings of the sealing grooves of the cathode plate and the anode plate are opposite to form an inter-plate sealing cavity; the sealing assembly comprises an integrated injection molding hydrogen field sealing ring, an air field sealing ring and an inter-plate sealing ring, the hydrogen field sealing ring and the air field sealing ring are respectively coated on two gas field sides of the sealing grooves on the unipolar plates, the height of the hydrogen field sealing ring and the height of the air field sealing ring are respectively greater than the protruding height of the flow channel, and the inter-plate sealing ring is filled in the inter-plate sealing cavity.

7. The bipolar plate assembly of claim 6, wherein: the height of the hydrogen field sealing ring is 1.2-1.5 times of the height of the bulge of the flow channel; the height of the air field sealing ring is 1.2-1.5 times of the height of the bulge of the flow channel;

the bipolar plate assembly also comprises an outer edge insulating sealing ring, and the outer edge insulating sealing ring is coated on the outer edges of the cathode plate and the anode plate; the height of the outer edge insulating sealing ring is 2.4-3 times of the height of the bulge of the flow channel.

8. A manufacturing process for manufacturing the bipolar plate assembly of claim 6 or 7; the manufacturing process comprises the following steps:

a stamping procedure: stamping the flow channel and the sealing groove on the base material, and forming the injection molding process hole in the groove wall of the sealing groove to obtain the unipolar plate;

sealing; attaching the two unipolar plates in a posture that the flow channel openings are opposite to each other, and assembling the bipolar plates; placing the bipolar plate into an injection mold, and injecting a sealing material, wherein the sealing material is filled in and out of the cavity of the inter-plate sealing cavity through the injection process hole, so that the integrated injection molding of the hydrogen field sealing ring, the air field sealing ring and the inter-plate sealing ring is completed; and obtaining the bipolar plate assembly after the sealing material is solidified.

9. An electric stack characterized by: comprising at least one biplate assembly according to claim 6 or 7.

10. A fuel cell vehicle including a fuel cell, characterized in that: the fuel cell includes at least one stack of claim 9.

Technical Field

The application belongs to the technical field of fuel cells, and particularly relates to a unipolar plate, a bipolar plate assembly, a manufacturing process, a galvanic pile and a fuel cell vehicle.

Background

A Proton Exchange Membrane Fuel Cell (PEMFC) is a power generation device that directly converts chemical energy into electrical energy using hydrogen as a fuel. The bipolar plate is an important core component of the fuel cell and plays roles of gas distribution, hydrothermal management, current collection and galvanic pile support. Hundreds of bipolar plates and membrane electrodes are stacked, and fastening force is applied through end plates on two sides to form the fuel cell stack.

The common material of the bipolar plate is a stainless steel sheet with the thickness of 0.07-0.1 mm, and the traditional bipolar plate manufacturing process comprises the following steps: punch forming → laser welding → coating → sealing. The method comprises the steps of stamping raw materials into a cathode plate and an anode plate with precise and micro flow channels, welding two unipolar plates together through laser to form a bipolar plate structure with two plates and three fields, coating the bipolar plate to improve the corrosion resistance of the bipolar plate, and filling a sealing material into a designed sealing line on the bipolar plate.

In the step of laser welding, the traditional scheme is that the cathode plate and the anode plate are sealed by laser welding, welding operation can generate certain adverse effect on a thin plate material, and the durability and the service performance are reduced. In the coating step, the currently used coating treatment mode is Physical Vapor Deposition (PVD), and the PVD coating process has high requirements on equipment and use cost (such as a vacuum pump and a high-voltage power supply), long preparation period and low coating yield. In the sealing step, a customized sealing ring is usually adhered to the bipolar plate, or a dispensing process is adopted, so that the sealing ring is easy to displace after long-term use, and sealing failure is caused.

In conclusion, the bipolar plate manufacturing process in the prior art has the technical problems of high production cost, long manufacturing period and low yield, and the prepared bipolar plate has poor durability and sealing performance.

Disclosure of Invention

In order to solve the above technical problems, the present invention provides a unipolar plate, a bipolar plate assembly and a manufacturing process thereof, a stack and a fuel cell vehicle, which greatly simplify the manufacturing process of the bipolar plate and improve the durability and sealing performance of the bipolar plate by improving the structure of the unipolar plate.

The technical scheme adopted for achieving the purpose of the invention is that the unipolar plate is provided with a raised flow channel and a sealing line for assembling a sealing ring, wherein the sealing line is provided with a sealing groove raised in the same direction as the flow channel, and the height of the projection of the sealing groove is smaller than that of the flow channel; at least one injection molding process hole penetrating through the groove wall is formed in the groove wall of the sealing groove.

Optionally, the seal groove includes a hydrogen port inner frame seal groove, an air port inner frame seal groove and an outer frame seal groove, the hydrogen port inner frame seal groove the air port inner frame seal groove the outer frame seal groove at least one of which is provided with the injection molding process hole.

Optionally, the edge of the unipolar plate is provided with a raised reinforcing rib, and the raised height of the reinforcing rib is equal to the raised height of the flow channel; the hydrogen mouth inner frame seal groove, the air mouth inner frame seal groove and the outer frame seal groove are all provided with the injection molding process hole.

Optionally, the edge of the unipolar plate is provided with a raised bending portion, and the raised height of the bending portion is smaller than the raised height of the flow channel; the hydrogen port inner frame sealing groove and the air port inner frame sealing groove are both provided with the injection molding process holes.

Optionally, the dimension of the injection molding process hole in the width direction of the sealing groove is 1/4-3/4 of the width of the groove bottom of the sealing groove; the hole pitch of the injection molding process holes is 5-50 mm; the unipolar plate is a precoated metal plate.

Based on the same inventive concept, the invention also correspondingly provides a bipolar plate assembly, which comprises a sealing assembly and two unipolar plates; the two unipolar plates are attached in a posture that the flow channel openings are opposite to each other to form a negative plate and a positive plate respectively; the openings of the sealing grooves of the cathode plate and the anode plate are opposite to form an inter-plate sealing cavity; the sealing assembly comprises an integrated injection molding hydrogen field sealing ring, an air field sealing ring and an inter-plate sealing ring, the hydrogen field sealing ring and the air field sealing ring are respectively coated on two gas field sides of the sealing grooves on the unipolar plates, the height of the hydrogen field sealing ring and the height of the air field sealing ring are respectively greater than the protruding height of the flow channel, and the inter-plate sealing ring is filled in the inter-plate sealing cavity.

Optionally, the height of the hydrogen field sealing ring is 1.2-1.5 times of the height of the bulge of the flow channel; the height of the air field sealing ring is 1.2-1.5 times of the height of the bulge of the flow channel;

the bipolar plate assembly also comprises an outer edge insulating sealing ring, and the outer edge insulating sealing ring is coated on the outer edges of the cathode plate and the anode plate; the height of the outer edge insulating sealing ring is 2.4-3 times of the height of the bulge of the flow channel.

Based on the same inventive concept, the invention also correspondingly provides a manufacturing process for manufacturing the bipolar plate assembly; the manufacturing process comprises the following steps:

a stamping procedure: stamping the flow channel and the sealing groove on the base material, and forming the injection molding process hole in the groove wall of the sealing groove to obtain the unipolar plate;

sealing; attaching the two unipolar plates in a posture that the flow channel openings are opposite to each other, and assembling the bipolar plates; placing the bipolar plate into an injection mold, and injecting a sealing material, wherein the sealing material is filled in and out of the cavity of the inter-plate sealing cavity through the injection process hole, so that the integrated injection molding of the hydrogen field sealing ring, the air field sealing ring and the inter-plate sealing ring is completed; and obtaining the bipolar plate assembly after the sealing material is solidified.

Based on the same inventive concept, the invention also correspondingly provides an electric pile comprising at least one bipolar plate assembly.

Based on the same inventive concept, the invention also correspondingly provides a fuel cell vehicle which comprises a fuel cell, wherein the fuel cell comprises at least one electric stack.

According to the technical scheme, the sealing line of the unipolar plate is provided with the convex sealing groove, the convex direction of the sealing groove is the same as the convex direction of the flow channel, and when the two unipolar plates are assembled into the bipolar plate, the flow channel openings of the two unipolar plates are opposite, and the sealing groove openings are opposite, so that an inter-plate sealing cavity is formed between the cathode plate and the anode plate. At least one injection molding process hole is formed in the groove wall of the sealing groove and penetrates through the groove wall of the sealing groove, so that the inside and the outside of the groove of the sealing groove can be communicated through the injection molding process hole. The bulge height of the sealing groove is smaller than that of the flow channel, so that a certain space is formed outside the sealing groove and can contain sealing materials. The structure allows the two unipolar plates to be assembled and then integrally formed into the sealing assembly by injection molding, the two unipolar plates are connected into a whole through the sealing assembly, and the sealing assembly serves as a welding wire, so that the welding step in the existing bipolar plate manufacturing process can be eliminated; and the plate sealing ring and the gas field side sealing ring are integrally formed, so that the sealing failure problem caused by cementation failure and displacement of the sealing ring in the prior art can be solved.

Based on the structure of the unipolar plates, the bipolar plate assembly provided by the invention comprises two unipolar plates and a sealing assembly fixedly connected with the unipolar plates, the negative plate and the positive plate are connected into a whole through the sealing assembly, the sealing assembly comprises a hydrogen field sealing ring, an air field sealing ring and an inter-plate sealing ring, and the hydrogen field sealing ring, the air field sealing ring and the inter-plate sealing ring can be integrally formed through injection molding as the injection molding process holes are communicated with the cavity and the cavity of the inter-plate sealing cavity. In the seal assembly: the hydrogen field sealing ring is coated on the hydrogen field side of the sealing groove on the anode plate and is used for sealing the hydrogen field between the anode plate and the membrane electrode; the air field sealing ring is coated on the air field side of the sealing groove on the negative plate and used for sealing the air field between the negative plate and the membrane electrode; the inter-plate sealing ring is filled in the inter-plate sealing cavity and used for sealing a water field inside the bipolar plate. The hydrogen field sealing washer and the air field sealing washer cladding respectively outside the seal groove, and the seal groove plays limiting displacement to hydrogen field sealing washer and air field sealing washer, further prevents that the sealing washer from shifting, leading to sealed inefficacy.

Based on the structure of the bipolar plate assembly, the bipolar plate assembly manufacturing process provided by the invention only comprises two steps of a stamping process and a sealing process, and compared with the bipolar plate manufacturing process of the prior art, namely stamping forming → laser welding → coating → sealing, the bipolar plate assembly manufacturing process provided by the invention is simplified, and the bipolar plate assembly manufacturing process is beneficial to realizing low-cost and high-efficiency production of the bipolar plate.

Compared with the prior art, the invention has the following advantages:

1. and a welding process is cancelled, so that the damage of welding to the substrate is avoided, and the durability and the corrosion resistance of the bipolar plate are improved. The bipolar plate manufacturing process is simplified from stamping forming → laser welding → coating → sealing into stamping forming → sealing, which is beneficial to realizing the low-cost and high-efficiency production of the bipolar plate.

2. The integrated molding of the sealing ring between the cathode plate and the anode plate, the sealing ring on the air field side of the cathode plate and the sealing ring on the hydrogen field side of the anode plate is realized only by once injection molding, the process is further simplified, the assembly of the cathode plate and the anode plate to the bipolar plate is completed simultaneously, the finished product of the bipolar plate is provided, and convenience is provided for the assembly of the galvanic pile.

3. The arrangement of the sealing grooves of the cathode plate and the anode plate plays a limiting role in the air field side sealing ring of the cathode plate and the hydrogen field side sealing ring of the anode plate, the sealing rings are not easy to shift and misplace after pressure is applied, and the sealing performance of the galvanic pile is improved.

Drawings

Fig. 1 is a front view of a single plate in embodiment 1 of the present invention.

Fig. 2 is a cross-sectional view a-a of the unipolar plate of fig. 1.

Fig. 3 is a sectional view a-a of the unipolar plate of fig. 1.

Fig. 4 is a cross-sectional view three taken along the line a-a of the unipolar plate of fig. 1.

Fig. 5 is a front view of the gas field side of a bipolar plate assembly in example 2 of the present invention.

Fig. 6 is a sectional view taken along line B-B of fig. 5.

Fig. 7 is a front view of the water field side of the bipolar plate assembly in example 2 of the present invention.

Fig. 8 is a front view of the gas field side of a bipolar plate assembly in example 3 of the present invention.

Fig. 9 is a cross-sectional view taken along line C-C of fig. 8.

Fig. 10 is a schematic structural view of a cell stack in embodiment 5 of the present invention.

Fig. 11 is a schematic structural view of a cell stack in embodiment 6 of the present invention.

Description of reference numerals: 100-unipolar plate, 101-hydrogen inlet, 102-air inlet, 103-cooling liquid inlet, 104-hydrogen outlet, 105-air outlet, 106-cooling liquid outlet; 110-a flow channel; 120-a sealing groove, 121-a hydrogen port inner frame sealing groove, 122-an air port inner frame sealing groove and 123-an outer frame sealing groove; 130-injection molding process holes; 140-reinforcing ribs; 150-bending part.

200-a bipolar plate assembly; 210-seal assembly, 211-hydrogen field seal ring, 212-air field seal ring, 213-inter-plate seal ring; 220-a cathode plate; 230-an anode plate; 240-outer edge insulating seal ring; 250-plate seal cavity; a-a hydrogen field; b-an air field; c-water field.

300-a membrane electrode; 400-end plate.

Detailed Description

In order to make the present application more clearly understood by those skilled in the art to which the present application pertains, the following detailed description of the present application is made with reference to the accompanying drawings by way of specific embodiments.

The bipolar plate manufacturing process aims to solve the technical problems of high production cost, long manufacturing period and low yield of the existing bipolar plate manufacturing process and the technical problems of poor durability and poor sealing performance of the manufactured bipolar plate. The embodiment of the invention provides a unipolar plate, a bipolar plate assembly, a manufacturing process, an electric pile and a fuel cell vehicle.

The invention will be described in detail with reference to the following drawings and specific embodiments:

example 1:

the embodiment of the invention provides a unipolar plate 100, wherein a raised flow channel 110 and a sealing line for assembling a sealing ring are arranged on the unipolar plate 100. The flow channel 110 extends along the length direction of the unipolar plate 100, the flow channel 110 protrudes outward, and the inside of the flow channel is used for cooling the membrane electrode by flowing a cooling liquid. Two ends of the unipolar plate 100 are respectively provided with 3 fluid inlets/outlets, namely a hydrogen inlet 101, an air inlet 102, a cooling liquid inlet 103, a hydrogen outlet 104, an air outlet 105, and a cooling liquid outlet 106. The path of the seal line is not modified in the present invention, i.e., the seal line of the present invention refers to the location on the bipolar plate for mounting the seal ring in the prior art. The sealing of the bipolar plate mainly comprises the sealing of a water field c between the cathode plate 220 and the anode plate 230 and the sealing between the cathode plate, the anode plate and the membrane electrode, so that the potential safety hazard caused by the gas leakage of hydrogen and air is prevented.

Referring to fig. 1 to 4, a convex sealing groove 120 is disposed on a sealing line of the unipolar plate 100, a convex direction of the sealing groove 120 is the same as a convex direction of the flow channel 110, when the two unipolar plates 100 are assembled into a bipolar plate, openings of the flow channel 110 of the two unipolar plates 100 are opposite, and openings of the sealing groove 120 are opposite, so that an inter-plate sealing cavity 250 is formed between the cathode plate 220 and the anode plate 230. At least one injection molding process hole 130 is formed in a groove wall of the sealing groove 120, and the injection molding process hole 130 penetrates through the groove wall of the sealing groove 120, so that the inside and the outside of the groove of the sealing groove 120 can be communicated through the injection molding process hole 130.

The protrusion height of the sealing groove 120 is smaller than that of the flow channel 110, so that a certain space is formed outside the sealing groove 120 to accommodate a sealing material, and the sealing effect is considered comprehensively, in the embodiment, the protrusion height H of the sealing groove 120 is 0.25-0.75 times of the protrusion height H of the flow channel 110, the cross section of the sealing groove is trapezoidal, and the draft angle of the side groove wall of the sealing groove is 5-15 degrees.

Because the injection molding process holes 130 can communicate with the front and back surfaces of the unipolar plate 100, sealing materials are present on both the front and back surfaces of the sealing line where the injection molding process holes 130 are disposed during injection molding. Therefore, the injection molding process hole 130 is suitable for being formed in an area where both the front and back sides of the unipolar plate 100 need to be sealed, for example, the inner frame of the coolant inlet/outlet port, the air field side needs to be provided with a sealing ring to prevent the coolant from entering the hydrogen field a/the air field b, the water field c side cannot be provided with a sealing ring, otherwise, the inflow and outflow of the coolant are blocked, and therefore the sealing line of the inner frame of the coolant inlet/outlet port cannot be formed with the injection molding process hole 130.

Therefore, referring to fig. 1, in the present embodiment, the sealing groove 120 includes a hydrogen port inner frame sealing groove 121, an air port inner frame sealing groove 122 and an outer frame sealing groove 123, at least one of the hydrogen port inner frame sealing groove 121, the air port inner frame sealing groove 122 and the outer frame sealing groove 123 is provided with an injection molding process hole 130, a dimension of the injection molding process hole 130 in the width direction of the sealing groove is 1/4-3/4 of the groove bottom width of the sealing groove 120, a hole pitch of the injection molding process hole 130 is 5-50 mm, an injection molding effect is prevented from being affected by too large pitch, and strength of the bipolar plate is affected by too small pitch.

The number, shape, area, and spacing of the injection molding process holes 130 are determined according to the actual size of the bipolar plate and the flowability of the sealing material, and the present invention is not limited thereto. In this embodiment, the hydrogen port inner frame sealing groove 121, the air port inner frame sealing groove 122 and the outer frame sealing groove 123 are all provided with injection molding process holes 130, the injection molding process holes 130 are circular holes, the injection molding process holes 130 are uniformly distributed, the aperture is half of the width of the groove bottom of the sealing groove 120, the hole pitch is 20-40 mm, and the specific numerical value is determined according to the actual size of the bipolar plate and the flowability of the sealing material.

In addition, since the injection molding process holes 130 can communicate with the front and back surfaces of the unipolar plate 100, sealing materials are present on both the front and back surfaces of the sealing line where the injection molding process holes 130 are disposed during injection molding. The sealing material can seal the water field c between the cathode plate 220 and the anode plate 230, and can seal the gap between the cathode plate and the membrane electrode, so as to meet the sealing requirement of the bipolar plate, therefore, no sealing line is arranged on the outer edge of the plate, and the unipolar plate 100 is only provided with the sealing groove 120, as shown in fig. 2.

In view of the support required for the edges of the plates, in some embodiments, the edges of the unipolar plates 100 are provided with raised ribs 140, as shown in fig. 3. The shape of the reinforcing ribs 140 is similar to that of the flow channel 110, and the reinforcing ribs 140 are all structures protruding out of the surface of the unipolar plate 100, and the protruding height of the reinforcing ribs 140 is equal to that of the flow channel 110, so that the reinforcing ribs 140 and the flow channel 110 can be simultaneously contacted with a membrane electrode after stacking, so as to support the membrane electrode, and ensure that an end plate uniformly presses a repeating unit (bipolar plate + membrane electrode).

To reduce the area of the unipolar plate 100 and increase the volumetric power density of the entire stack, in some embodiments, the edges of the unipolar plate 100 are provided with raised bends 150, as shown in fig. 4. The bending portion 150 is a material of the edge of the unipolar plate 100, and due to the bending, the bending portion 150 protrudes from the surface of the unipolar plate 100, and after the two unipolar plates 100 are assembled in a butt joint manner, an accommodating cavity with an opening can be formed between the two bending portions 150, so that a sealing material can be accommodated. The protruding height of the bent portion 150 should be less than the protruding height of the flow channel 110, so that the gas field side of the bent portion 150 has a certain space capable of accommodating a sealing material, thereby achieving bipolar plate sealing.

In addition, since the bent portion 150 still has an opening after the two unipolar plates 100 are assembled, and the opening faces outward, when the bent portion 150 is injection-molded with a sealing material, the sealing material may be simultaneously filled inside and outside the accommodation cavity, and thus the bent portion 150 may serve as an outer edge sealing line of the unipolar plates 100. That is, the bending portion 150 forms the outer frame sealing groove 123, and therefore, in the corresponding embodiment, the injection molding process holes 130 are only formed in both the hydrogen port inner frame sealing groove 121 and the air port inner frame sealing groove 122.

In order to simplify the process operation of stacking the unipolar plates 100, the unipolar plates 100 in this embodiment are pre-coated metal plates, such as pre-coated steel strip products provided by SANDVIK (santvkk corporation), and the strips treated by the roll-to-roll coating technique are coated by themselves, so that the coating process after the formation of the unipolar plates is not required, and the coating step in the existing process can be eliminated.

Therefore, the unipolar plate 100 provided by the embodiment allows the two unipolar plates 100 to be integrally formed into the sealing assembly 210 through injection molding after being assembled, the two unipolar plates 100 are connected into a whole through the sealing assembly 210, and the sealing assembly 210 serves as a welding line, so that a welding step in the existing bipolar plate manufacturing process can be omitted, and the corrosion resistance of the bipolar plate is prevented from being influenced by damage of laser welding on a precoat layer; and the plate sealing ring and the gas field side sealing ring are integrally formed, so that the sealing failure problem caused by cementation failure and displacement of the sealing ring in the prior art can be solved.

Example 2:

based on the same inventive concept, the present embodiment provides a bipolar plate assembly 200, which is different from the prior art in that the bipolar plate assembly only includes two unipolar plates 100 without connection, referring to fig. 5 to 7, the bipolar plate assembly 200 provided by the present embodiment includes two unipolar plates 100 connected by a sealing assembly 210 into a whole, the unipolar plate 100 in the present embodiment adopts the unipolar plate 100 of the above-mentioned embodiment 1, and the two unipolar plates 100 are attached in a posture that the openings of the flow channels 110 are opposite to each other, so as to respectively form a cathode plate 220 and an anode plate 230. The openings of the sealing grooves 120 of the cathode plate 220 and the anode plate 230 are opposite, and the two sealing grooves 120 at opposite positions form a closed inter-plate sealing cavity 250, so that the cavity inside and the cavity outside of the inter-plate sealing cavity 250 are communicated due to the existence of the injection molding process hole 130.

The seal assembly 210 includes a hydrogen field seal 211, an air field seal 212, and an interpanel seal 213 that are integrally injection molded through the injection tooling holes 130. The height of the hydrogen field sealing ring 211 and the air field sealing ring 212 should be greater than the height H of the protrusion of the flow channel 110, so that the hydrogen field sealing ring 211 and the air field sealing ring 212 can be pressed during stacking. In order to ensure uniform pressure, the heights of the hydrogen field sealing ring 211 and the air field sealing ring 212 should be equal, and in this embodiment, the heights of the hydrogen field sealing ring 211 and the air field sealing ring 212 are both 1.2 to 1.5 times of the height H of the protrusion of the flow channel 110.

The hydrogen field sealing ring 211 and the air field sealing ring 212 are respectively coated on the gas field sides of the sealing grooves 120 of the two unipolar plates 100, specifically, the hydrogen field sealing ring 211 is coated on the hydrogen field a side of the sealing groove 120 of the anode plate 230, and the wall of the whole sealing groove 120 is completely embedded into the hydrogen field sealing ring 211 for sealing the hydrogen field a between the anode plate 230 and the membrane electrode; the air field sealing ring 212 is wrapped on the air field b side of the sealing groove 120 of the cathode plate 220, and the groove wall of the whole sealing groove 120 is completely embedded in the air field sealing ring 212 for sealing the air field b between the cathode plate 220 and the membrane electrode. An inter-plate packing 213 is filled in the inter-plate seal cavity 250 for sealing the water field c inside the bipolar plate.

In the sealing assembly 210, the hydrogen field sealing ring 211 and the air field sealing ring 212 are respectively wrapped outside the sealing groove 120, and the sealing groove 120 has a limiting effect on the hydrogen field sealing ring 211 and the air field sealing ring 212, so that the sealing ring is further prevented from being displaced and sealing failure is further prevented.

Example 3:

based on the same inventive concept, the present embodiment provides a bipolar plate assembly 200, and like embodiment 2, the bipolar plate assembly 200 of the present embodiment also includes two unipolar plates 100 connected together by a sealing assembly 210, and the unipolar plate 100 of embodiment 1 is used as the unipolar plate 100 in the present embodiment. The bipolar plate assembly 200 of the present embodiment includes all the technical features of the bipolar plate assembly 200 of embodiment 2, and therefore, the same portions are not described herein again, and refer to embodiment 2 specifically.

Referring to fig. 8 and 9 in particular, in the present embodiment, the outer edge of the bipolar plate assembly 200 is provided with an outer edge insulating sealing ring 240, and the outer edge insulating sealing ring 240 is wrapped on the outer edges of the cathode plate 220 and the anode plate 230, that is, the outer edge insulating sealing ring 240 can not only realize insulation and sealing between the cathode plate 220, the anode plate 230 and the membrane electrode, but also realize insulation and sealing between the edge of the bipolar plate assembly 200 and the stack fastener. Also, the outer edge insulating seal 240 may also serve to support the edges of the bipolar plates and membrane electrode. The outer edge insulating sealing ring 240 is of an integrated structure, and the overall height of the outer edge insulating sealing ring 240 is 2.4-3 times of the height H of the protrusion of the flow channel 110, namely the height of the outer edge insulating sealing ring 240 in the hydrogen field a and the air field b is 1.2H-1.5H.

Because the outer edge insulating sealing ring 240 is added, the leakage of the bipolar plate can be prevented, and the insulating property of the galvanic pile is improved. In addition, even if the sealing assembly 210 fails, the outer edge insulating seal ring 240 can also play a role in sealing, thereby preventing gas leakage and further improving the safety and reliability of the fuel cell stack.

Example 4:

based on the same inventive concept, the present embodiment provides a manufacturing process for manufacturing the bipolar plate assembly 200 of embodiment 2 or embodiment 3 described above.

Referring to fig. 5 to 9, the manufacturing process includes the steps of:

a stamping procedure: the runner 110 and the sealing groove 120 are stamped on the substrate, and an injection molding process hole 130 is formed in the groove wall of the sealing groove 120, so as to obtain the unipolar plate 100.

Specifically, in the embodiment, the base material is a precoated metal plate, and the stamping of the sealing groove 120 and the punching of the injection molding process hole 130 are simultaneously completed in the stamping process of the runner 110. And then entering a sealing process.

Sealing; attaching two unipolar plates 100 in a posture that the openings of the flow channels 110 are opposite to each other, and assembling the bipolar plates; placing the bipolar plate into an injection mold, injecting a sealing material, and filling the sealing material into and out of the inter-plate sealing cavity 250 through the injection process hole 130 to complete the integrated injection molding of the hydrogen field sealing ring 211, the air field sealing ring 212 and the inter-plate sealing ring 213; after the sealing material is cured, a bipolar plate assembly 200 is obtained.

Specifically, before injection molding, an adhesive is coated on the surfaces of the cathode plate 220 and the anode plate 230, which are in contact with the sealing material, in advance, so that the subsequent integrated injection molding sealing ring is conveniently adhered to the bipolar plate.

Assembling the cathode plate 220 and the anode plate 230 into a bipolar plate according to the assembly requirement, putting the bipolar plate into an injection mold for pressing, and uniformly injecting a sealing material, wherein the specific sealing material can adopt ethylene propylene diene monomer, silicon rubber or fluororubber. The integrated single injection molding of the hydrogen field sealing ring 211, the air field sealing ring 212 and the inter-plate sealing ring 213 is completed through the injection molding process hole 130. And after the injection molding is finished, taking the bipolar plate out of the injection mold, and stacking for use after curing.

For the bipolar plate assembly 200 with the outer edge insulating seal ring 240, the injection molding of the outer edge insulating seal ring 240 is simultaneously completed when the seal assembly 210 is injection molded.

The manufacturing process of the bipolar plate assembly 200 provided by the embodiment only comprises two steps of a stamping process and a sealing process, and compared with the bipolar plate manufacturing process of the prior art, namely stamping forming → laser welding → coating → sealing, the manufacturing process of the bipolar plate assembly 200 provided by the invention is simplified, and the bipolar plate assembly is beneficial to realizing low-cost and high-efficiency production.

Example 5:

based on the same inventive concept, the embodiment provides a stack, and a typical stack structure sequentially includes an air inlet end plate, an air inlet end insulating plate, an air inlet end current collecting plate, a repeating unit, a blind end current collecting plate, a blind end insulating plate, and a blind end plate. The whole pile is fixed through the pile fastener, and the end plates at the two ends provide certain pressure for the repeating units, so that the sealing ring deforms under pressure, and a good sealing effect is realized.

Referring to fig. 10, the present embodiment provides a stack in which at least one bipolar plate assembly 200 of embodiment 2 described above is provided in a repeating unit, and thus the present embodiment provides a stack having all the advantages of embodiment 2 described above. Other structures of the electric pile in the embodiment which are not described in detail can refer to relevant disclosures in the prior art, and are not described herein.

During stacking, hundreds of bipolar plate assemblies 200 and the membrane electrode 300 are stacked together in a crossed manner, fastening force is applied through the end plates 400 at the two ends and the fastening pieces, so that the hydrogen field sealing ring 211, the air field sealing ring 212 and the inter-plate sealing ring 213 are compressed and deformed, water, hydrogen and air are sealed in respective flow fields, and the assembly of the fuel cell stack is completed.

Example 6:

based on the same inventive concept, the present embodiment provides a stack, referring to fig. 11, in which at least one bipolar plate assembly 200 of the above-described embodiment 3 is disposed in a repeating unit, and thus the present embodiment provides the stack with all the advantages of the above-described embodiment 3. Other structures of the electric pile in the embodiment which are not described in detail can refer to relevant disclosures in the prior art, and are not described herein.

Example 7:

based on the same inventive concept, the present embodiment provides a fuel cell vehicle, which includes a fuel cell, wherein the fuel cell uses hydrogen as fuel, directly converts chemical energy into electric energy, and converts high-voltage electric energy into three-phase alternating current through DCDC to drive a motor to rotate and output power.

A single electric pile can be arranged in the fuel cell, and a plurality of electric piles can be integrated together to improve the output power of the fuel cell. The fuel cell of the present embodiment includes at least one of the stacks of embodiment 5 or embodiment 6 described above, and thus the present embodiment provides the fuel cell vehicle having all the advantages of embodiment 5 or embodiment 6 described above. Other detailed structures of the fuel cell vehicle in the present embodiment can refer to the related disclosures of the prior art, and will not be described herein.

While the preferred embodiments of the present application have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all alterations and modifications as fall within the scope of the application.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.