Electrochemical scanning etching processing device and method for bipolar plate of fuel cell

Abstract

The invention discloses an electrochemical scanning and etching processing device and method for a bipolar plate of a fuel cell. The electrochemical scanning and etching processing device comprises an FDM mask module, an electrochemical scanning and etching module and a slide rail working platform, the FDM mask module comprises a two-dimensional motion platform located on the left side of the marble platform; the electrochemical scanning etching module comprises a mounting frame located on the right side of the marble platform, the mounting frame is fixedly connected with the marble platform through bolts, a mounting seat is connected with the middle of the mounting frame through bolts, and an electrolyte nozzle is fixedly mounted on the mounting seat; the sliding rail working platform comprises a transverse sliding rail fixed to the marble platform, a working table used for containing workpieces is connected to the transverse sliding rail in a sliding mode, and the two ends of the transverse sliding rail extend to the positions below the corresponding nozzles and the electrolyte nozzles. The FDM mask module and the electrochemical scanning etching module are integrated, high-precision, high-strength and long-service-life printing can be achieved, and meanwhile the property of a printing material can be controlled by adjusting electrochemical parameters.

Description

Technical Field

[0001] The invention relates to electrochemistry, and in particular to an electrochemical scanning etching processing device and method for a fuel cell bipolar plate. Background Art

[0002] With the continuous development of advanced equipment manufacturing industries such as high-power integrated circuits and high-power lasers, the demand for efficient cooling technology is increasing. Microchannel phase change cooling technology is considered to be the key to solving related technical bottlenecks. The key to the microchannel phase change cooling system lies in its tiny channel size and precise closed channel structure. However, such a microscale and complex structural design poses great challenges to traditional mechanical processing technology. Traditional processing methods are difficult to accurately control the size and shape of the channel at the micron level, and it is difficult to handle the processing and manufacturing of closed microchannels. To overcome these challenges, research and industry are currently exploring more advanced micromachining technologies, such as electrochemical deposition processing technology and 3D printing technology. These high-precision and high-efficiency micromachining technologies can not only achieve precise manufacturing of microchannel structures, but also improve the performance of phase change cooling systems through fine design optimization; 3D printing technology, also known as additive manufacturing technology, builds three-dimensional objects by stacking materials layer by layer. This technology breaks the limitations of traditional manufacturing technology. It has significant advantages in speed, flexibility and customization, and has become one of the main technologies for manufacturing phase change cooling systems. Especially in the precise manufacturing of microchannels, 3D printing technology can achieve high precision and complex structures that are difficult to achieve with traditional processing, greatly improving the design flexibility and heat exchange efficiency of the cooling system. Although 3D printing technology has the above advantages in the field of phase change cooling, it also has some limitations and challenges. Although 3D printing can manufacture complex microchannel structures, material deposition during the printing process may introduce surface roughness and affect cooling performance. Summary of the invention

[0003] In order to overcome the problems of insufficient precision, insufficient strength, poor bonding force, etc. in 3D printing technology, the present invention has invented a fuel cell bipolar plate electrochemical scanning etching processing device and method, which integrates FDM mask module and electrochemical scanning etching module. First, a resin mask layer with a certain pattern is printed using fuse deposition forming technology, and then a metal layer of phase change cooling enthusiasm is printed on the hollow part of the mask layer using electrochemical deposition technology. The masking and deposition processes are repeated alternately until the phase change cooling enthusiasm is printed in layers, and finally the resin mask layer and the metal enthusiasm are separated. High-precision, high-strength, and long-life printing can be achieved, and the properties of the printed material can be controlled by adjusting the electrochemical parameters.

[0004] The technical solution adopted by the present invention is: a fuel cell bipolar plate electrochemical scanning etching processing device, including an FDM mask module, an electrochemical scanning etching module, and a slide rail working platform; The FDM mask module includes a two-dimensional motion platform located on the left side of the marble platform, an axial horizontal connecting beam is fixedly connected to the X-direction slider of the two-dimensional motion platform, a connecting plate is fixedly installed on the end of the connecting beam, an output end is fixedly connected to the connecting plate, the top of the output end is a material inlet, and the lower end is composed of an electric heating device and a nozzle; The electrochemical scanning etching module includes a mounting frame located on the right side of the marble platform, the mounting frame is fixedly connected to the marble platform by bolts, the mounting seat is connected to the middle of the mounting frame by bolts, and an electrolyte nozzle is fixedly installed on the mounting seat; The slide rail working platform comprises a transverse slide rail fixed on a marble platform, a workbench for placing workpieces is slidably connected to the transverse slide rail, and two ends of the transverse slide rail extend to below the corresponding nozzles and electrolyte nozzles.

[0005] In the above scheme, as a preference, a partition is provided on the marble platform, which, after being enclosed by a partition fixed on the marble platform, divides the area on the marble platform into a sealed left space and a right space, the left space is located on the left side of the partition, and the right space is located on the right side of the partition, and the partition has a through hole, and the two-dimensional motion platform includes a vertical column fixedly connected to the marble platform and located in the left space, an X-axis slide rail is slidably connected to the vertical column, the X-axis slide rail is slidably connected to the X-axis slider, the connecting beam passes through the through hole and is connected to the connecting plate, the connecting plate is fixedly connected to one end of the conical protective cover, and the other end of the conical protective cover is fixed on the partition and covers the through hole.

[0006] In the above scheme, preferably, one end of the mounting seat is a hollow cylinder, the inner diameter of the hollow cylinder is slightly smaller than the radius of the cylindrical part above the electrolyte nozzle, and the electrolyte nozzle is fixed by geometric closure constraint.

[0007] In the above scheme, as a preference, the transverse slide rail includes a screw rod, both ends of which are rotatably mounted on a screw mounting seat, the screw mounting seat is fixed on the slide rail base, a waterproof motor box is fixedly mounted on the screw mounting seat, the motor in the waterproof motor box is connected to the screw rod through transmission, the workbench is fixed on a slide rail waterproof platform connected to the screw rod and acting as a slider, and an accordion cover is installed between the two sides of the slide rail waterproof platform and the corresponding screw mounting seats.

[0008] In the above scheme, preferably, the accordion cover material is high temperature resistant nylon cloth.

[0009] In the above scheme, as a preferred embodiment, a connecting seat is fixed on the top of the slide rail waterproof platform, and the connecting seat has screw holes and is connected to the working platform 503 by bolts.

[0010] In the above scheme, preferably, the conical protective cover includes a side connecting plate 603 for fixedly connecting with the connecting plate and the partition, and a high-temperature resistant sealing ring arranged between the side connecting plate and the corresponding connecting plate and the partition. The two side connecting plates are connected by sealing leather and have air holes at the lower end.

[0011] A method for electrochemical scanning etching of a fuel cell bipolar plate, using the device to perform processing, Phase 1: The workpiece is initially located on the FDM mask module. The extreme position of the workpiece on the workbench can be used as the installation and positioning reference of the overall part. The main control panel of the two-dimensional motion platform is opened to perform positioning reference and initial processing gap through the main control panel of the two-dimensional motion platform. Then, the processing parameters are set through the active panel, the Y-axis reciprocating motion is adjusted, and the initial processing gap between the nozzle and the anode workpiece is set. At this time, the electric heating device heats the nozzle position alone to melt the resin material and realize the resin mask layer on the workpiece. The second stage: the workpiece is moved from the FDM mask module to the electrochemical scanning etching module through a horizontal slide; sodium chloride or sodium nitrate solution is used as the electrolyte, the anode and cathode are connected to the positive and negative poles of the DC power supply respectively, the mounting seat of the electrochemical scanning etching module is connected to the negative pole of the power supply as the workpiece cathode, the working platform is connected to the positive pole of the power supply as the tool anode, a DC or pulse power supply is connected between the cathode and the anode, and a certain voltage is applied; the electrolyte pump continuously transports the electrolyte to the processing area, and the electrolyte carries the processed products back to the electrolytic cell; the material is removed from the anode surface in the form of ions, and as the cathode is continuously fed, the anode is finally processed into shape.

[0012] Compared with the prior art, the present invention has the following beneficial effects: The integrated FDM mask module and electrochemical scanning etching module can realize the synchronous etching of complex patterns through simple reciprocating scanning motion, which will significantly improve processing efficiency and reduce processing costs.

[0013] By using the insulating mask layer, the global electric field in traditional electrochemical machining is discretized into multiple local fields. Each local field only covers one machining area. The electric field in the non-machining area is completely shielded by the insulating mask layer, completely eliminating the influence of stray corrosion in the non-machining area. The tool electrode scans along the workpiece surface, significantly shortening the electrolyte flow, greatly reducing the impact of byproducts such as bubbles and Joule heat during processing, and improving the controllability and stability of the processing; The processed fuel cell bipolar plates have a larger contact area in actual use, which increases the reaction rate, not only saving costs but also achieving a higher cost-effectiveness. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of machine tool distribution; Figure 2 It is a schematic diagram of the overall structure of the FDM mask processing device; Figure 3 It is a schematic diagram of the overall structure of the electrochemical scanning etching processing device; Figure 4 It is a schematic diagram of the transverse slide rail seal; Figure 5 It is a schematic diagram of the sealing of the protective cover in the processing area; Names of the numbers in the figure: 1-machine tool, 2-marble platform, 3-FDM mask module, 4-electrochemical scanning etching module, 5-horizontal slide, 6-conical protective cover, 301-vertical column, 302-X-axis slide, 303-connecting beam, 304-material inlet, 305-nozzle, 306-electric heating device, 307-workpiece, 308-mask plate, 401-mounting frame, 402-mounting seat, 403-electrolyte nozzle, 404-fuel cell bipolar plate, 501-waterproof motor box, 502-slide rail waterproof platform, 503-workbench, 504-keel frame, 505-screw mounting seat, 506-sealing gasket, 507-slide rail base, 508-accordion cover, 601-sealing leather, 602-high temperature resistant sealing ring, 603-side connecting plate, 604-air vent. DETAILED DESCRIPTION

[0015] The present invention will be further described below by way of examples, but the scope of the present invention is not limited thereto.

[0016] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0017] A fuel cell bipolar plate electrochemical scanning etching processing device, comprising an FDM mask module, an electrochemical scanning etching module, and a slide rail working platform; The FDM mask module 3 includes a two-dimensional motion platform 3 located on the left side of the marble platform 2, an axially horizontal connecting beam 303 is fixedly connected to the X-direction slider of the two-dimensional motion platform, a connecting plate is fixedly installed on the end of the connecting beam 303, an output end is fixedly connected to the connecting plate, the top of the output end is a material inlet 304, and the lower end is composed of an electric heating device 306 and a nozzle 305; The electrochemical scanning etching module 4 includes a mounting frame 401 located on the right side of the marble platform 2, the mounting frame 401 is fixedly connected to the marble platform 2 by bolts, a mounting seat 402 is connected to the middle of the mounting frame 401 by bolts, and an electrolyte nozzle 403 is fixedly installed on the mounting seat 402; The slide rail working platform includes a transverse slide rail 5 fixed on a marble platform, and a workbench 503 for placing workpieces is slidably connected to the transverse slide rail 5. Both ends of the transverse slide rail 5 extend to below the corresponding nozzles and electrolyte nozzles.

[0018] Wherein, the marble platform 2 is installed on the machine tool 1.

[0019] There is a partition on the marble platform 2. After the partition is surrounded by the area fixed on the marble platform 2, the area on the marble platform 2 is divided into a sealed left space and a right space. The left space is located on the left side of the partition, and the right space is located on the right side of the partition. The partition has a through hole. The two-dimensional motion platform 3 includes a vertical column 301 fixedly connected to the marble platform 2 and located in the left space. An X-axis slide rail 302 is slidably connected to the vertical column. The X-axis slide rail is slidably connected to the X-axis slider. The connecting beam passes through the through hole and is connected to the connecting plate. The connecting plate is fixedly connected to one end of the conical protective cover 6, and the other end of the conical protective cover 6 is fixed on the partition and covers the through hole.

[0020] One end of the mounting seat 402 is a hollow cylinder, the inner diameter of which is slightly smaller than the radius of the cylindrical portion above the electrolyte nozzle 403 , and the electrolyte nozzle 403 is fixed by geometric closure constraints.

[0021] The transverse slide rail includes a screw rod 504 (located inside the accordion cover), both ends of the screw rod are rotatably mounted on the screw mounting seat 505, the screw mounting seat 505 is fixed on the slide rail base 507, a waterproof motor box 501 is fixedly mounted on the screw mounting seat 505, the motor transmission in the waterproof motor box 501 is connected to the screw rod, the workbench is fixed on the slide rail waterproof platform 502 which is connected to the screw rod and acts as a slider, and an accordion cover 508 is installed between the two sides of the slide rail waterproof platform and the corresponding screw mounting seats.

[0022] The material of the accordion cover 508 is high-temperature resistant nylon cloth. Since sporadic sparks, high temperatures, electrolyte corrosion, etc. may occur during processing, the material of the accordion cover is high-temperature resistant nylon cloth, which is not only waterproof, dustproof, and oil-proof, but is also commonly used in environments with sporadic sparks. In addition, the accordion cover completes telescopic movement during operation, and a sliding rail waterproof platform is installed between the accordion covers. Sealing gaskets 506 are installed between the two sides of the sliding rail waterproof platform and the accordion cover. When the working platform moves laterally, the electrolyte sprayed by the electrochemical scanning etching module will not cause corrosion to the sliding rail, thereby achieving a sealing effect.

[0023] A connecting seat is fixed on the top of the slide rail waterproof platform, and a screw hole is provided on the connecting seat, which is connected to the working platform 503 by bolts.

[0024] The non-processing area of ​​the FDM mask module is sealed by a conical protective cover, which includes a side connecting plate 603 for fixed connection with the connecting plate and the partition, and a high temperature resistant sealing ring 602 arranged between the side connecting plate and the corresponding connecting plate and the partition. The two side connecting plates are connected by a sealing leather 601, and the lower end has a vent hole 604. The middle uses a sealing leather, which is a standard PUR material with chemical properties such as waterproof and anti-corrosion. The lower end has a vent hole, which is at the bottom to balance the pressure on both sides, and some small water droplets caused by the small vent hole do not affect the use, in order to prevent the protective cover from being vacuum-tight in the fixed space and reduce the expansion and depression caused by movement.

[0025] Electrochemical scanning etching uses the electrochemical reaction of the anode metal to remove the material from the workpiece surface in the form of ions. During the machining process, the electrolyte flows through the machining gap to provide a medium for the electrochemical reaction and promptly remove the products generated on the cathode and anode surfaces. With the continuous feeding of the tool cathode, the workpiece shape that meets the requirements is finally machined. In order to achieve geometric size and geometric shape machining, some specific process conditions must be met, such as maintaining a very small machining gap between the cathode and the anode, usually between 0.1mm-1mm; the electrolyte has a high flow rate through the machining gap, generally in the range of 6m / s-30m / s. The high flow rate of the electrolyte can promptly remove the anode dissolution products and the Joule heat generated by the electrolytic machining process. At the same time, the flowing electrolyte also has the effect of reducing polarization.

[0026] The workpiece is initially located in the FDM mask module. The extreme positions of the workpiece 307 and the mask plate 308 on the workbench can be used as the installation and positioning reference of the overall parts to achieve accurate positioning and correction of the parts and reduce errors. The main control program panel of the two-dimensional motion platform is opened, and the positioning reference and initial processing gap are set through the main control program panel of the two-dimensional motion platform. Then, the processing parameters are set through the active panel, and the Y-axis reciprocating motion is adjusted to set the initial processing gap between the nozzle and the cathode workpiece. At this time, the electric heating device heats the nozzle position alone to melt the resin material and perform a resin mask layer on the workpiece. The FDM mask module has two degrees of freedom. Since the work platform moves horizontally in the horizontal direction, the mask plate can be processed into a hollow shape of the required shape.

[0027] The workpiece is moved from the FDM mask module to the electrochemical scanning etching module through a lateral slide; the electrolyte nozzle is fixed on the right side of the box, and the module is equivalent to a rack. Since the working platform moves horizontally in the horizontal direction, it has only one degree of freedom, and the electrolyte nozzle can realize a lateral scanning function. At this time, the electrolyte flows in at high speed through the water inlet pipe and flows out at high speed through the water outlet. According to the processing needs of the staff, a suitable position can be selected to spray the electrolyte, so that the electrolyte will not corrode the mask plate but only the workpiece, and then the electrochemical processing technology is used to process the hollowed-out part of the mask layer to produce the final formed workpiece (fuel cell bipolar plate) 404.

[0028] Sodium chloride or sodium nitrate solution is used as the electrolyte. The anode and cathode are connected to the positive and negative poles of the DC power supply respectively. The mounting base of the electrochemical scanning etching module is connected to the negative pole of the power supply as the workpiece cathode, and the working platform is connected to the positive pole of the power supply as the tool anode. A DC or pulse power supply is connected between the cathode and the anode to apply a certain voltage; the electrolyte pump continuously transports the electrolyte to the processing area, and the electrolyte carries the processed products back to the electrolytic cell; the material is removed from the anode surface in the form of ions, and as the cathode is continuously fed, the anode is finally processed and formed.

[0029] It should be noted that the embodiments described above are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described with reference to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words, rather than restrictive words. The present invention may be modified as specified within the scope of the claims of the present invention, and the present invention may be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein, on the contrary, the present invention can be extended to all other methods and applications with the same functions.

Claims

1. A fuel cell bipolar plate electrochemical scanning etching processing device, characterized in that: Including FDM mask module, electrochemical scanning etching module, and slide rail working platform; The FDM mask module (3) comprises a two-dimensional motion platform (3) located on the left side of the marble platform (2), an axially horizontal connecting beam (303) is fixedly connected to the X-direction slider of the two-dimensional motion platform, a connecting plate is fixedly installed at the end of the connecting beam (303), an output end is fixedly connected to the connecting plate, the top of the output end is a material inlet (304), and the lower end is composed of an electric heating device (306) and a nozzle (305); The electrochemical scanning etching module (4) comprises a mounting frame (401) located on the right side of the marble platform (2), the mounting frame (401) being fixedly connected to the marble platform (2) by bolts, a mounting seat (402) being connected to the middle part of the mounting frame (401) by bolts, and an electrolyte nozzle (403) being fixedly mounted on the mounting seat (402); The slide rail working platform comprises a transverse slide rail (5) fixed on a marble platform, a workbench (503) for placing workpieces being slidably connected to the transverse slide rail (5), and two ends of the transverse slide rail (5) extending to below the corresponding nozzle and electrolyte nozzle.

2. The electrochemical scanning etching processing device for a fuel cell bipolar plate according to claim 1, characterized in that: The marble platform (2) is provided with a partition, and the partition and the area fixed on the marble platform (2) are combined to divide the area on the marble platform (2) into a sealed left space and a right space, the left space is located on the left side of the partition, and the right space is located on the right side of the partition. The partition has a through hole, and the two-dimensional motion platform (3) includes a vertical column (301) fixedly connected to the marble platform (2) and located in the left space, an X-direction slide rail is slidably connected to the vertical column, and the X-direction slide rail is slidably connected to the X-direction slider, and the connecting beam passes through the through hole and is connected to the connecting plate, and the connecting plate is fixedly connected to one end of the conical protective cover (6), and the other end of the conical protective cover (6) is fixed to the partition and covers the through hole.

3. The electrochemical scanning etching processing device for a fuel cell bipolar plate according to claim 1, characterized in that: One end of the mounting seat (402) is a hollow cylinder, the inner diameter of which is slightly smaller than the radius of the cylindrical portion above the electrolyte nozzle (403), and the electrolyte nozzle (403) is fixed by geometric closure constraints.

4. The electrochemical scanning etching processing device for a fuel cell bipolar plate according to claim 2, characterized in that: The transverse slide rail comprises a lead screw (504), both ends of which are rotatably mounted on a lead screw mounting seat (505), the lead screw mounting seat (505) is fixed on a slide rail base (507), a waterproof motor box (501) is fixedly mounted on the lead screw mounting seat (505), a motor in the waterproof motor box (501) is connected to the lead screw, a workbench is fixed on a slide rail waterproof platform connected to the lead screw and acting as a slider, and an accordion cover (508) is installed between two sides of the slide rail waterproof platform and the corresponding lead screw mounting seats.

5. The electrochemical scanning etching processing device for a fuel cell bipolar plate according to claim 4, characterized in that: The material of the accordion cover (508) is high temperature resistant nylon cloth.

6. The electrochemical scanning etching processing device for a fuel cell bipolar plate according to claim 4, characterized in that: A connecting seat is fixed on the top of the slide rail waterproof platform, and a screw hole is provided on the connecting seat, which is connected to the working platform (503) by bolts.

7. The electrochemical scanning etching processing device for a fuel cell bipolar plate according to claim 2, characterized in that: The conical protective cover comprises a side connecting plate (603) for fixedly connecting to the connecting plate and the partition plate, and a high temperature resistant sealing ring (602) arranged between the side connecting plate and the corresponding connecting plate and the partition plate. The two side connecting plates are connected by a sealing leather (601) and have a ventilation hole (604) at the lower end.

8. A method for electrochemical scanning etching of a fuel cell bipolar plate, using the apparatus as described in any one of claims 1 to 7, characterized in that: Phase 1: the workpiece is initially located at the FDM mask module, and the extreme position of the workpiece (307) on the workbench (503) can be used as the installation and positioning reference of the overall part; the main control program panel of the two-dimensional motion platform is opened, and the positioning reference and initial processing gap are set through the main control program panel of the two-dimensional motion platform (3), and then the processing parameters are set through the active panel, the Y-axis reciprocating motion is adjusted, and the initial processing gap between the nozzle (305) and the anode workpiece is set. At this time, the electric heating device heats the nozzle (305) position alone to melt the resin material and realize the resin mask layer on the workpiece; The second stage: the workpiece is moved from the FDM mask module to the electrochemical scanning etching module via the lateral slide rail (5); sodium chloride or sodium nitrate solution is used as the electrolyte, the anode and cathode are connected to the positive and negative poles of the DC power supply respectively, the mounting base of the electrochemical scanning etching module is connected to the negative pole of the power supply as the workpiece cathode, the working platform is connected to the positive pole of the power supply as the tool anode, a DC or pulse power supply is connected between the cathode and the anode, and a certain voltage is applied; The electrolyte pump continuously delivers electrolyte to the processing area, and the electrolyte carries the processed products back to the electrolytic cell; the material is removed from the anode surface in the form of ions, and as the cathode continues to feed, the anode is finally processed into shape.

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