Hot-pressing mold and method for manufacturing conductive composite plate

Abstract

The present application relates to the technical field of battery preparation, and specifically relates to a hot-pressing mold and a manufacturing method of a conductive composite plate, wherein the hot-pressing mold comprises a mold plate, a vacuum assembly and a heating assembly; the mold plate has a first cavity; the vacuum assembly comprises a first plate body, a second cavity is enclosed between the first plate body and the mold plate, the second cavity is communicated with the first cavity through a first vent hole arranged on the mold plate, one side of the first plate body facing the mold plate is provided with a suction hole, an air duct is arranged in the first plate body, one end of the air duct is communicated with the suction hole, and the other end of the air duct is used for being communicated with a vacuum device; the heating assembly comprises a second plate body and a heating unit, the second plate body is arranged in the second cavity, and a plurality of heating units are distributed along the longitudinal direction and the transverse direction of the second plate body at intervals. The present application can overcome the technical problems that the existing manufacturing process of the conductive composite plate has low exhaust efficiency, is prone to generate trapped air bubbles in the product, causes poor resin fusion effect, and limits the use performance of the conductive composite plate.

Description

Technical Field

[0001] This invention relates to the field of battery manufacturing technology, and in particular to a hot pressing mold and a method for manufacturing conductive composite electrode plates. Background Technology

[0002] Conductive composite plates are core components of flow storage and fuel cell stacks, primarily responsible for conducting circuit current, distributing reaction fluids, isolating individual cells, and supporting the overall stack structure. Their density, conductivity, and structural strength directly determine the stack's power generation efficiency, sealing performance, and cycle life. Currently, conductive resin composite plates have become the mainstream substrate for conductive composite plates due to their excellent conductivity, resistance to acid and alkali corrosion, good mechanical toughness, and controllable manufacturing costs.

[0003] Currently, the industry commonly uses atmospheric pressure hot pressing molding process for conductive composite plates: Modified conductive resin is uniformly coated onto the surface of a conductive substrate, and after lamination and assembly according to thickness requirements to obtain a hot-pressed blank, the blank is placed in the template of a hot-pressing mold. The high temperature and pressure generated by the combined heating and pressurizing devices melt the resin, filling the internal pores of the substrate. After cooling and solidification, the finished plate is obtained. This molding process has a low barrier to entry and is suitable for mass production, but it has the following technical drawbacks:

[0004] (1) The problem of air bubble retention is prominent: the conductive composite substrate is a porous composite structure. A large amount of air will be sealed inside the micropores of the substrate and the gaps between the layers of the multilayer board. Under normal pressure hot pressing conditions, the inside of the template is in a closed state. During the pressurization process, the air cannot be discharged on its own and is squeezed to form micron-level closed air bubbles, which are retained in the resin colloid and the interface between the substrate and the resin for a long time.

[0005] (2) Poor resin fusion effect: Residual air bubbles will directly hinder the flow and penetration of molten conductive resin. The resin cannot fill the deep micropores of the substrate, and defects such as local lack of glue, internal voids, and interlayer gaps are likely to occur, resulting in insufficient overall density of the electrode plate.

[0006] (3) Limited product performance: The high-resistivity insulation region formed by bubbles will increase the volume resistivity and surface resistivity of the electrode plate, resulting in uneven current distribution inside the stack; at the same time, bubbles are prone to stress concentration, and the electrode plate is very prone to delamination, cracking, leakage and other faults under long-term charging and discharging and alternating hot and cold conditions.

[0007] (4) The exhaust scheme has great limitations: At present, manufacturers only rely on two methods: static exhaust during the hot pressing preheating stage and slow heating to assist exhaust. These methods can only exhaust the air in the large pores on the surface of the substrate, but cannot remove the trapped bubbles in the deep micropores. The exhaust efficiency is extremely low, and it cannot solve the molding defects caused by bubbles from the root cause. This results in a low yield rate of process products and high production costs. Summary of the Invention

[0008] The purpose of this invention is to overcome the technical problems of low exhaust efficiency in existing conductive composite electrode manufacturing processes, which easily generate trapped air bubbles inside the product, resulting in poor resin fusion and limited performance of conductive composite electrodes. The invention provides a hot pressing mold and a method for manufacturing conductive composite electrodes.

[0009] In a first aspect, the present invention provides a hot pressing mold, including a template, a vacuum assembly, and a heating assembly; the template has a first chamber for receiving a hot-pressed blank; the vacuum assembly includes a first plate connected to one side of the template, the first plate and the template forming a second chamber, the second chamber communicating with the first chamber through a first ventilation hole provided on the template, an adsorption hole provided on the side of the first plate facing the template, an air passage provided inside the first plate, one end of the air passage communicating with the adsorption hole, and the other end of the air passage communicating with a vacuum device; the heating assembly includes a second plate and heating units, the second plate being disposed in the second chamber, and a plurality of heating units being distributed at intervals along the longitudinal and transverse directions of the second plate, the heating effect of each heating unit being independently controllable.

[0010] Preferably, a number of raised strips are distributed at intervals on the inner wall of the first chamber near the first plate, and the first ventilation hole is disposed between two adjacent raised strips.

[0011] Preferably, the second plate is provided with a second ventilation hole, one end of which is connected to the first ventilation hole, and the other end of which is connected to the adsorption hole.

[0012] Preferably, the side of the template facing the first plate has a groove, and the second plate is disposed in the groove.

[0013] Preferably, the template includes an upper mold and a lower mold, a first sealing ring is provided between the upper mold and the lower mold, and the first sealing ring surrounds the first cavity; a second sealing ring is provided between the first plate and the template, and the second sealing ring surrounds the second cavity.

[0014] Preferably, the gas passage includes longitudinal channels, transverse channels, and vertical channels; the longitudinal channels are arranged along the longitudinal direction of the first plate, and a plurality of longitudinal channels are distributed at intervals along the transverse direction of the first plate, with at least one end of the longitudinal channel being used to communicate with a vacuum device; the transverse channels are arranged along the transverse direction of the first plate, and a plurality of transverse channels are distributed at intervals along the longitudinal direction of the first plate, with at least one end of the transverse channel being used to communicate with a vacuum device; the vertical channels are arranged along the thickness direction of the first plate, with one end of the vertical channel communicating with an adsorption hole, and the other end of the vertical channel communicating with the intersection of the longitudinal channel and the transverse channel.

[0015] Preferably, the heating unit is a resistance heating element.

[0016] In a second aspect, the present invention provides a method for manufacturing a conductive composite electrode plate, applied to a hot pressing mold of the present invention, comprising the following steps: S1. Prepare hot-pressed blanks by placing the hot-pressed blanks in the first cavity of the template.

[0017] S2. Start the vacuum device and evacuate the first chamber through the vacuum assembly; start the heating assembly and heat the hot-pressed blank to the first temperature range through the heating unit, and wait for the predetermined holding time; heat the hot-pressed blank to the second temperature range through the heating unit, and the temperature of the second temperature range is higher than the temperature of the first temperature range.

[0018] S3. Use a pressurizing device to pressurize the template and transform the hot-pressed blank into a molded blank.

[0019] S4. Turn off the vacuum device and heating components, unload the pressure of the template, remove the molded blank from the template and perform post-processing to obtain the conductive composite electrode plate.

[0020] Preferably, S3 further includes the following steps: S31. Use a pressurizing device to pressurize the template to the first pressure range and wait for the first predetermined pressure holding time.

[0021] S32. Use a pressurizing device to pressurize the template to the second pressure range. The pressure in the second pressure range is greater than the pressure in the first pressure range. Wait for the second predetermined pressure holding time.

[0022] Preferably, in S2, when the hot-pressed blank is heated by the heating unit, the heating power of the heating unit is made higher the further away from the center of the template.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. This invention provides a hot pressing mold, in which a heating component and a vacuum component are connected to one side of the mold. During the hot pressing process, the heating component can heat the hot pressing blank to the hot pressing molding temperature. Since the hot pressing component includes several independently controllable heating units, this invention can apply different heating effects to different positions of the hot pressing blank according to the temperature requirements of different stages of hot pressing molding, thereby improving the temperature uniformity of the hot pressing blank and avoiding defects such as inconsistent resin melting caused by local overheating or local insufficient temperature. This is beneficial to improving the fusion effect between the resin and the substrate and reducing the pressure of air removal inside the resin.

[0024] The vacuum component can extract the gas inside the first chamber of the template according to the extraction path of the first chamber - first ventilation hole - second chamber - adsorption hole - air channel - vacuum device, thereby creating negative pressure in the first chamber. This can not only further reduce the exhaust pressure of air inside the pores of the hot-pressed blank, but also actively extract the trapped air in the shallow and deep micropores and interlayer gaps of the hot-pressed blank. The heating component and the vacuum component work together to completely eliminate the squeezing and blocking effect of air bubbles on the molten resin, allowing the resin to fully coat the composite substrate and fill the pores in all directions under the condition of no air resistance. Therefore, the fusion effect of resin and substrate, the performance of conductive composite electrode plate, yield and production cost of this invention are all superior to the prior art.

[0025] 2. This invention provides a method for manufacturing a conductive composite electrode plate. By using the hot pressing mold of this invention to hot press the hot pressing blank, combined with a gradient heating strategy, the resin melting effect and blank forming stability can be improved, thereby improving the performance and yield of the conductive composite electrode plate. Attached Figure Description

[0026] Figure 1 This is an exploded three-dimensional structural diagram of a hot pressing mold according to the present invention; Figure 2 This is a top view of a hot pressing mold according to the present invention; Figure 3 yes Figure 2 Schematic diagram of the cross-sectional structure of section AA; Figure 4 This is a top view schematic diagram of the heating assembly of a hot pressing mold according to the present invention; Figure 5 This is a top view schematic diagram of the vacuum assembly of a hot pressing mold according to the present invention; Figure 6 This is a top cross-sectional view of a vacuum assembly of a hot pressing mold according to the present invention. Figure 7 yes Figure 2 Schematic diagram of the cross-sectional structure of section BB; Figure 8 yes Figure 2 Schematic diagram of the cross-sectional structure of the CC section; icon: 100 - Template; 110 - First ventilation hole; 120 - Raised strip; 130 - Groove; 140 - First sealing ring; 200 - First plate; 210 - Adsorption hole; 220 - Air passage; 221 - Longitudinal channel; 222 - Transverse channel; 223 - Vertical channel; 230 - Second sealing ring; 240 - Vacuum adsorption tube; 250 - Vacuum device; 300 - Second plate; 310 - Heating unit; 320 - Second ventilation hole. Detailed Implementation

[0027] The present invention will now be described in further detail with reference to specific embodiments. However, this should not be construed as limiting the scope of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0028] Unless otherwise specified, the use of terms such as "upper," "lower," "left," "right," "center," "inner," and "outer" to indicate orientation or positional relationships in the description of specific embodiments of the present invention is based on the orientation or positional relationships shown in the accompanying drawings, or the orientation or positional relationship in which the product / equipment / device is typically placed during use. These terms are merely for the purpose of facilitating the description of the present invention or simplifying the description in specific embodiments, enabling those skilled in the art to quickly understand the solution, and do not indicate or imply that a particular device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, they should not be construed as limitations on the present invention.

[0029] Furthermore, the use of terms such as "horizontal," "vertical," "suspended," and "parallel" does not imply that the corresponding device / component / element must be absolutely horizontal, vertical, suspended, or parallel, but rather that it can be slightly tilted or have a deviation. For example, "horizontal" merely means that its direction is more horizontal relative to "vertical," not that the structure must be completely horizontal, but that it can be slightly tilted. Alternatively, it can be simplified to mean that the corresponding device / component / element, when set in a "horizontal," "vertical," "suspended," or "parallel" direction, can have an error / deviation of ±10% relative to the corresponding direction, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, and more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still achieve its function in the present invention.

[0030] Furthermore, the use of terms such as "first," "second," and "third" in terminology is merely for distinguishing descriptions of identical or similar components and should not be interpreted as emphasizing or implying the relative importance of a particular component.

[0031] Furthermore, in the description of the embodiments of the present invention, "several", "more than", and "a number of" represent at least two. The number can be any number, such as 2, 3, 4, 5, 6, 7, 8, or 9, and can even exceed nine.

[0032] Furthermore, in the description of the technical solution of this invention, unless otherwise explicitly specified / limited / restricted, the terms "set up," "install," "connect," "link," "provided with," "laid out," and "arranged" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to common connection methods in the art, such as welding, riveting, bolting, and threaded connections. Such connections can be mechanical, electrical, or communication connections; they can be direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components.

[0033] Example 1 like Figures 1 to 8 As shown, a hot press mold includes a template 100, a vacuum assembly, and a heating assembly.

[0034] Template 100 has a first chamber for receiving hot-pressed preform.

[0035] A vacuum assembly includes a first plate 200 connected to one side (e.g., bottom, top, or side) of a template 100; the first plate 200 and the template 100 enclose a second chamber, which is connected to the first chamber via a first ventilation hole 110 on the template 100, allowing air in the first chamber to enter the second chamber through the ventilation hole 110; an adsorption hole 210 is provided on the side of the first plate 200 facing the template 100, and an air passage 220 is provided inside the first plate 200. One end of the air passage 220 extends to the side of the first plate 200 facing the template 100 and communicates with the adsorption hole 210, while the other end extends to other sides of the first plate 200 (e.g., the bottom or side) and is used to communicate with a vacuum device 250, allowing the vacuum device 250 to extract air from the second chamber through the air passage 220.

[0036] The heating assembly includes a second plate 300 and heating units 310. The second plate 300 is disposed in the second chamber. Several heating units 310 are distributed at intervals along the longitudinal and transverse directions of the second plate 300. The heating units 310 can heat the hot-pressed blank in the first chamber, and the heating effect of each heating unit 310 can be controlled independently, so that different heating effects can be produced at different positions of the hot-pressed blank. The heating effect includes heating parameters such as heating power and maximum temperature.

[0037] exist Figures 1 to 8 The various directions in this embodiment are also labeled using a Cartesian coordinate system, where the X-axis represents the longitudinal direction of the first plate 200 and the second plate 300, the Y-axis represents the transverse direction of the first plate 200 and the second plate 300, and the Z-axis represents the height direction, which is also the thickness direction of the first plate 200 and the normal direction of the template 100.

[0038] In this embodiment, a heating component and a vacuum component are connected to one side of the template 100. During the hot pressing process, the heating component can heat the hot pressing blank to the hot pressing molding temperature. Since the hot pressing component includes several independently controllable heating units 310, this embodiment can apply different heating effects to different positions of the hot pressing blank according to the temperature requirements of different stages of hot pressing molding, thereby improving the temperature uniformity of the hot pressing blank and avoiding defects such as inconsistent resin melting caused by local overheating or insufficient local temperature. This is beneficial to improving the fusion effect between the resin and the substrate and reducing the pressure of air removal inside the resin.

[0039] The vacuum component can extract the gas inside the first chamber of the template 100 according to the extraction path of the first chamber - first ventilation hole 110 - second chamber - adsorption hole 210 - air channel 220 - vacuum device 250, thereby creating a negative pressure in the first chamber. This can further reduce the exhaust pressure of air inside the pores of the hot-pressed blank, and actively extract the trapped air in the shallow and deep micropores and interlayer gaps of the hot-pressed blank. The heating component and the vacuum component work together to completely eliminate the squeezing and blocking effect of air bubbles on the molten resin, allowing the resin to fully coat the composite substrate and fill the pores in all directions under the condition of no air resistance. Therefore, the fusion effect of resin and substrate, the performance of conductive composite plate (such as resistivity and cycle life), yield and production cost are all better than the prior art in this embodiment.

[0040] In an optional embodiment, to increase the contact area between the vacuum assembly and the template 100, and between the heating assembly and the template 100, the vacuum assembly is connected to one side of the template 100 along its normal direction; for example... Figure 1 , Figure 7 and Figure 8 As shown, both the heating component and the vacuum component are connected to the lower surface of the template 100.

[0041] In an optional embodiment, the template 100 itself can adopt existing technology, only requiring a first ventilation hole 110 to be provided on the inner wall of the first chamber near the vacuum component to connect the first chamber and the second chamber; for example, the template 100 can include an upper mold and a lower mold, which are detachably connected (e.g., threaded connection, tenon connection, or snap-fit ​​connection); when the upper mold and the lower mold are connected, a first chamber for accommodating the hot-pressed blank can be formed between the upper mold and the lower mold; when the upper mold and the lower mold are separated, the first chamber is open, and the operator can put the hot-pressed blank into the first chamber or take the hot-pressed blank out of the first chamber; the first ventilation hole 110 is provided on the lower mold and penetrates the lower mold along the height direction, so that the upper end of the first ventilation hole 110 is connected to the first chamber and the lower end of the first ventilation hole 110 is connected to the second chamber.

[0042] In an optional embodiment, a first sealing ring 140 is provided between the upper mold and the lower mold. The first sealing ring 140 surrounds the first chamber, thereby improving the sealing performance of the first chamber and preventing external air from entering the first chamber and causing the vacuum level of the first chamber to deteriorate.

[0043] In an optional embodiment, a plurality of protrusions 120 are spaced apart on the inner wall of the first chamber near the first plate 200, and a first ventilation hole 110 is disposed between two adjacent protrusions 120. Thus, when the hot-pressed blank is placed in the first chamber, even if the hot-pressed blank is pressed against the inner wall of the first chamber where the first ventilation hole 110 is disposed and is in contact with the protrusions 120, there is still a gap between the first ventilation hole 110 and the hot-pressed blank. This can prevent the first ventilation hole 110 from being blocked or blocked by the hot-pressed blank, which is beneficial to improving the exhaust reliability and exhaust efficiency of the first ventilation hole 110.

[0044] In an optional embodiment, the length of the protrusions 120 is arranged along the longitudinal direction of the first plate 200, and a plurality of protrusions 120 are distributed at intervals along the transverse direction of the first plate 200; a plurality of first ventilation holes 110 are provided between each pair of adjacent protrusions 120, and the first ventilation holes 110 between adjacent pairs of protrusions 120 are distributed at intervals along the longitudinal direction of the first plate 200, so that the first ventilation holes 110 between all the protrusions 120 can be opened as follows: Figure 2 The rectangular array shown can increase the total effective exhaust area of ​​the first ventilation hole 110 and shorten the length of the extraction path, enabling the vacuum assembly to generate a better vacuum in the first chamber. It can also improve the compatibility of this hot-pressing mold with the irregularly shaped conductive composite electrode plate.

[0045] In optional implementations, such as Figure 3 As shown, the template 100 has a groove 130 on the side facing the first plate 200, so that when the template 100 and the first plate 200 are connected to each other, the groove 130 can form a second chamber; the second plate 300 is disposed in the groove 130, which can make the structure of this hot press mold more compact and reduce the vertical space occupied; and can also reduce the thickness of the template 100, so that the heating component can heat the hot press blank in the first chamber more quickly.

[0046] In an optional embodiment, the second plate 300 is provided with a second ventilation hole 320, such as... Figure 4 and Figure 7As shown, the second ventilation hole 320 is disposed in the gap between each heating unit 310. One end of the second ventilation hole 320 is connected to the first ventilation hole 110, and the other end of the second ventilation hole 320 is connected to the adsorption hole 210, thereby preventing the second plate 300 from blocking the adsorption hole 210, which would prevent the vacuum assembly from successfully evacuating the first chamber. When the second plate 300 is provided with the second ventilation hole 320, the evacuation path in this embodiment is: first chamber - first ventilation hole 110 - second chamber - second ventilation hole 320 - adsorption hole 210 - air passage 220 - vacuum device 250.

[0047] In optional embodiments, the heating unit 310 may employ various existing technologies, including but not limited to infrared heating devices, steam heating devices, thermal oil heating devices, or resistance heating devices.

[0048] In an optional embodiment, the heating unit 310 is a resistance heating element with a very small thickness, which is extremely suitable for this embodiment where vertical space is limited.

[0049] In an optional embodiment, a second sealing ring 230 is provided between the first plate 200 and the template 100. The second sealing ring 230 surrounds the second chamber, thereby improving the sealing performance of the second chamber and preventing external air from entering the second chamber and causing the vacuum level of the second chamber to deteriorate.

[0050] In an optional embodiment, the number of adsorption pores 210 is at least four, and the adsorption pores 210 are evenly distributed along the longitudinal and transverse directions of the first plate 200, thereby forming a configuration such as... Figure 5 The rectangular array shown can increase the total effective exhaust area of ​​the adsorption holes 210 and shorten the length of the pumping path, making it easier for the vacuum assembly to generate a better vacuum in the first chamber. It can also improve the compatibility of this hot-pressing mold with the irregularly shaped conductive composite electrode plate.

[0051] In an optional embodiment, when the number of adsorption holes 210 is at least four, depending on actual needs, each adsorption hole 210 can be provided with a separate air channel 220, and each air channel 220 can be connected to a separate vacuum device 250, so as to control the vacuum degree inside each air channel 220 and the suction force of each adsorption hole 210 respectively, thereby improving the uniformity of the vacuum degree in the first chamber and preventing the local air pressure from being too high or too low from having a negative impact on the exhaust and molding of the hot-pressed blank; or the air channels 220 connected to each adsorption hole 210 can be interconnected to synchronously control the vacuum degree of each air channel 220.

[0052] In optional embodiments, the specific structural form of the air passage 220 includes, but is not limited to, an independent pipe component connected to the first plate 200, or a hole structure processed inside the first plate 200.

[0053] In optional implementations, such as Figure 7 and Figure 8 As shown, the air passage 220 includes a longitudinal passage 221, a transverse passage 222, and a vertical passage 223. The longitudinal passage 221 is arranged along the longitudinal direction of the first plate 200, and a plurality of longitudinal passages 221 are distributed at intervals along the transverse direction of the first plate 200. At least one end of the longitudinal passage 221 is used to communicate with the vacuum device 250, for example, both ends are connected to the vacuum device 250 or one end is connected to the vacuum device 250 while the other end is blocked. The transverse passage 222 is arranged along the transverse direction of the first plate 200, and a plurality of transverse passages 222 are distributed at intervals along the longitudinal direction of the first plate 200. At least one end of the transverse passage 222 is used to communicate with the vacuum device 250. The vertical passage 223 is arranged along the thickness direction of the first plate 200. One end of the vertical passage 223 is connected to the adsorption hole 210, and the other end of the vertical passage 223 is connected to the intersection of the longitudinal passage 221 and the transverse passage 222. This embodiment can create a grid-like air passage 220 inside the first plate 200, which is beneficial to improving the vacuum efficiency of the vacuum device 250 in the first chamber, and also to improving the uniformity of the vacuum degree inside the vacuum assembly, preventing the negative impact of excessively high or low local air pressure on the exhaust and molding of the hot-pressed blank.

[0054] In optional implementations, such as Figure 6 As shown, a vacuum adsorption tube 240 is provided at one end of each longitudinal channel 221 and at one end of each transverse channel 222. A vacuum device 250 (e.g., a vacuum pump or a vacuum generator) can be connected to the vacuum adsorption tube 240 to generate a vacuum in the air channel 220.

[0055] Example 2 A method for manufacturing a conductive composite electrode plate, applied to a hot pressing mold in Example 1, includes the following steps: S1. Prepare hot-pressed blanks by placing the prepared hot-pressed blanks into the first chamber of template 100.

[0056] S2. Start the vacuum device 250 to evacuate the first chamber through the vacuum assembly, maintaining the vacuum level of the first chamber within a predetermined vacuum range; start the heating assembly to perform gradient heating of the hot-pressed blank through the heating unit 310: first, heat the hot-pressed blank to the first temperature range to melt the resin. Wait for a predetermined holding time to allow the resin to soften initially and for trapped air in the shallow pores of the substrate to be fully expelled. Then, heat the hot-pressed blank to the second temperature range through the heating unit 310. The temperature of the second temperature range is higher than that of the first temperature range, reaching the resin hot-pressing molding temperature.

[0057] S3. Use a pressurizing device (such as a hydraulic system, pneumatic system or servo system) to pressurize the template 100 and transform the hot-pressed blank into a molded blank.

[0058] S4. Turn off the vacuum device 250 and the heating component, unload the pressure of the template 100 at a predetermined rate, and after the molded blank has cooled to room temperature, remove the molded blank from the template 100 and perform post-processing to obtain a conductive composite electrode plate.

[0059] In an optional implementation, S1 specifically includes the following steps: S11. Substrate pretreatment: Select resin-based conductive composite substrate as the base material. Remove surface dust and impurities by wiping and high-pressure air blowing. Then place it in a constant temperature oven for high-temperature drying at 80℃~100℃ for 20min~30min to remove adsorbed moisture. After drying, cut according to the electrode plate design size for later use.

[0060] S12, Coating and Lamination: Prepare modified conductive resin adhesive and apply it evenly to both sides of the substrate using spraying or roller coating methods; according to the product thickness requirements, stack the corresponding number of coated substrates to complete the lamination assembly and prepare the hot-pressed blank.

[0061] S13. Mold sealing: Place the assembled hot-pressed blank into the first chamber of the mold, close the mold (for example, cover the lower mold with the upper mold), press the first sealing ring 140 to complete the sealing of the first chamber, check the airtightness of the first chamber to ensure there are no leaks.

[0062] In an optional embodiment, when the hot-pressed blank is heated by the heating unit 310 in S2, the heating power of the heating unit 310 is made higher the further away from the center of the template 100, and the change in the heating power of the heating unit 310 can be either gradient or continuous. This embodiment can compensate for the temperature difference caused by the heat dissipation rate at the edge of the mold being greater than that at the center of the mold, thereby improving the temperature uniformity of the hot-pressed blank and avoiding the defect of overheating at the center and insufficient temperature at the edge.

[0063] In an optional embodiment, if each adsorption hole 210 is provided with an air passage 220, when the hot-pressed blank is heated by the vacuum assembly in S2, the adsorption holes 210 near the center of the template 100 and the adsorption holes 210 near the edge of the template 100 can have different suction forces, thereby improving the uniformity of the vacuum degree in the first chamber and preventing the local air pressure from being too high or too low from having a negative impact on the exhaust and molding of the hot-pressed blank.

[0064] In an optional embodiment, when S2 evacuates the first chamber using the vacuum assembly, the predetermined vacuum range is -0.07MPa to -0.095MPa, with a fluctuation error ≤ ±0.005MPa.

[0065] In an optional embodiment, when heating the hot-pressed blank in S2, the heating rate is controlled at 3℃ / min to 5℃ / min, the first temperature range is 120℃ to 140℃, the predetermined holding time is 1min to 3min, and the second temperature range is 160℃ to 185℃.

[0066] In an optional implementation, S3 further includes the following steps: S31. Use a pressurizing device to pressurize the template 100 to the first pressure range and wait for the first predetermined pressure holding time so that the deep micropore bubbles of the hot-pressed billet can be fully discharged.

[0067] S32. Use a pressurizing device to pressurize the template 100 to the second pressure range. The pressure in the second pressure range is greater than the pressure in the first pressure range. Wait for the second predetermined pressure holding time to allow the molten resin to fully impregnate the composite substrate, achieve dense filling of the resin, and complete the integrated molding.

[0068] This embodiment adopts a segmented pressurization mode, which can avoid the problems of glue overflow and substrate damage caused by single high pressure, and also creates sufficient conditions for the discharge of deep micropore bubbles in the hot-pressed blank. When combined with the gradient heating strategy, it can help the manufacturing method of this conductive composite electrode plate to further balance the degassing efficiency, improve the resin melting effect and blank forming stability, thereby further improving the performance and yield of the conductive composite electrode plate.

[0069] In an optional embodiment, the first pressure range, the second pressure range, the first predetermined holding time, and the second predetermined holding time can be dynamically adjusted according to specific conditions such as substrate thickness and number of layers; for example, the first pressure range can be 0.5MPa~1.5MPa, the first predetermined holding time can be 1min~3min, the second pressure range can be 2.5MPa~4.5MPa, and the second predetermined holding time can be 3min~5min.

[0070] In an optional implementation, the post-processing in S4 includes trimming and polishing the formed blank.

[0071] In an optional implementation, after the heating components are turned off in S4, the template 100 and the forming blank are allowed to cool down naturally, with the cooling rate controlled at 2℃ / min to 4℃ / min.

[0072] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hot press mold, comprising a template (100) having a first chamber for receiving a hot press blank; characterized in that, Also includes: A vacuum assembly includes a first plate (200) connected to one side of a template (100), the first plate (200) and the template (100) forming a second chamber, the second chamber communicating with the first chamber through a first ventilation hole (110) provided on the template (100), an adsorption hole (210) provided on the side of the first plate (200) facing the template (100), an air passage (220) provided inside the first plate (200), one end of the air passage (220) communicating with the adsorption hole (210), and the other end of the air passage (220) communicating with a vacuum device (250); The heating assembly includes a second plate (300) and heating units (310). The second plate (300) is disposed in the second chamber. A plurality of heating units (310) are distributed at intervals along the longitudinal and transverse directions of the second plate (300). The heating effect of each heating unit (310) can be independently controlled.

2. The hot pressing mold according to claim 1, characterized in that, The first chamber has a plurality of protrusions (120) spaced apart on the inner wall near the first plate (200), and the first ventilation hole (110) is disposed between two adjacent protrusions (120).

3. A hot pressing mold according to claim 2, characterized in that, The second plate (300) is provided with a second ventilation hole (320), one end of the second ventilation hole (320) is connected to the first ventilation hole (110), and the other end of the second ventilation hole (320) is connected to the adsorption hole (210).

4. A hot pressing mold according to any one of claims 1 to 3, characterized in that, The template (100) has a groove (130) on the side facing the first plate (200), and the second plate (300) is disposed in the groove (130).

5. A hot pressing mold according to any one of claims 1 to 3, characterized in that, The template (100) includes an upper mold and a lower mold. A first sealing ring (140) is provided between the upper mold and the lower mold, and the first sealing ring (140) surrounds the first cavity. A second sealing ring (230) is provided between the first plate (200) and the template (100), and the second sealing ring (230) surrounds the second cavity.

6. A hot pressing mold according to any one of claims 1 to 3, characterized in that, The airway (220) includes a longitudinal channel (221), a transverse channel (222) and a vertical channel (223); The longitudinal channel (221) is arranged along the longitudinal direction of the first plate (200), and a plurality of the longitudinal channels (221) are distributed at intervals along the transverse direction of the first plate (200). At least one end of the longitudinal channel (221) is used to communicate with the vacuum device (250). The transverse channel (222) is arranged transversely along the first plate (200), and a plurality of the transverse channels (222) are distributed at intervals along the longitudinal direction of the first plate (200). At least one end of the transverse channel (222) is used to communicate with the vacuum device (250). The vertical channel (223) is arranged along the thickness direction of the first plate (200). One end of the vertical channel (223) is connected to the adsorption hole (210), and the other end of the vertical channel (223) is connected to the intersection of the longitudinal channel (221) and the transverse channel (222).

7. A hot pressing mold according to any one of claims 1 to 3, characterized in that, The heating unit (310) is a resistance heating element.

8. A method for manufacturing a conductive composite electrode plate, characterized in that, The application of a hot pressing mold according to any one of claims 1 to 7 includes the following steps: S1. Prepare hot-pressed blank by placing the hot-pressed blank in the first cavity of the template (100); S2. Start the vacuum device (250) to evacuate the first chamber through the vacuum assembly; start the heating assembly to heat the hot-pressed blank to the first temperature range through the heating unit (310) and wait for the predetermined heat preservation time; The hot-pressed blank is heated to a second temperature range by the heating unit (310), and the temperature of the second temperature range is higher than that of the first temperature range. S3. Pressurize the template (100) using a pressurizing device to transform the hot-pressed blank into a molded blank; S4. Turn off the vacuum device (250) and the heating component, unload the pressure of the template (100), take out the molded blank from the template (100) and perform post-processing to obtain a conductive composite electrode plate.

9. A method for manufacturing a conductive composite electrode plate according to claim 8, characterized in that, S3 also includes the following steps: S31. Use a pressurizing device to pressurize the template (100) to the first pressure range and wait for the first predetermined pressure holding time; S32. Use a pressurizing device to pressurize the template (100) to the second pressure range. The pressure in the second pressure range is greater than the pressure in the first pressure range. Wait for the second predetermined pressure holding time.

10. A method for manufacturing a conductive composite electrode plate according to any one of claims 8 to 9, characterized in that, In S2, when the hot-pressed blank is heated by the heating unit (310), the heating power of the heating unit (310) is made higher the further away from the center of the template (100).

Images