Preparation method of injection molding copper bar, injection molding copper bar and motor controller

Abstract

The invention provides a preparation method of an injection molding copper bar, the injection molding copper bar and a motor controller, relates to the technical field of injection molding, and solves the problem that the safety and stability of a motor controller system are affected due to poor performance of the injection molding copper bar in related technologies. The resin is injected into the pits in the surface of the copper bar, so that the resin and the metal form high-strength combination, compact combination is achieved, the bonding strength of the prepared injection-molded copper bar is higher, the performance of the copper bar can be improved, the overall performance of a motor controller system is improved, and the service life of the motor controller system is prolonged. And the stability and the safety of the motor controller system during operation can be improved.

Description

Technical Field

[0001] The present application relates to the field of injection molding technology, and in particular to a method for preparing an injection-molded copper busbar, an injection-molded copper busbar, and a motor controller. Background Art

[0002] New energy vehicles are gradually becoming the mainstream of the development of the automotive industry due to their low emissions and high energy efficiency. In its system structure, the motor controller system is one of its core parts. The motor controller system is used to convert the direct current of the battery into the alternating current required by the motor to drive the motor. The high-pressure injection copper busbar is a key component in the motor controller system. It undertakes the task of transmitting large currents, and its performance directly affects the efficiency and reliability of the motor controller system; while the through-cylinder sealing structure is to prevent electrical connection between the inside of the motor controller system and the external environment, ensuring the safety and stability of the motor controller system.

[0003] Therefore, in the motor controller system, the design of the high-pressure injection-molded copper busbar and the cylinder sealing structure is particularly important. In the related art, the high-pressure injection-molded copper busbar is usually designed with a corresponding glue filling groove, and the glue filling groove is glued to achieve sealing; or the glue is pre-wetted, and then the wet glue is fixed and squeezed through the plastic-coated copper busbar bolts to achieve sealing. However, the bonding strength of the injection-molded copper busbar formed by the above method is poor. In the corresponding performance tests such as durability tests and aging tests, its bonding strength is poor, and it is easy to fall off, which in turn has an adverse effect on the stable operation of the motor controller system. In this regard, the performance of the injection-molded copper busbar provided in the related art is poor and it is easy to affect the safety and stability of the motor controller system. Summary of the invention

[0004] The present application provides a method for preparing an injection-molded copper busbar, an injection-molded copper busbar and a motor controller, which solves the problem in the related art that the performance of the injection-molded copper busbar is poor and affects the safety and stability of the motor controller system. The present solution can form an injection-molded copper busbar with high bonding strength, thereby improving the stability and safety of the motor controller system during operation.

[0005] In a first aspect, the present application provides a method for preparing an injection-molded copper busbar, the method comprising:

[0006] The copper busbar to be prepared is subjected to corrosion treatment by an electrolytic cell to form pits on the surface of the copper busbar;

[0007] Use a cleaning agent to clean the copper busbar after corrosion treatment;

[0008] The copper busbar is baked at a preset temperature for a preset time to solidify the pits formed on the surface of the copper busbar;

[0009] Under preset temperature and pressure conditions, the copper busbar is subjected to high-pressure injection molding using resin in an injection mold to fill the resin in the pits on the surface of the copper busbar and form an injection-molded copper busbar.

[0010] In a second aspect, the present application further provides an injection-molded copper busbar, which is prepared by the injection-molded copper busbar preparation method as described above.

[0011] In a third aspect, the present application further provides a motor controller, which includes the injection-molded copper busbar as described in the second aspect.

[0012] The preparation method of the present application scheme forms pits on the surface of the copper busbar by electrolytic corrosion, and injects resin into the nano-scale pits on the surface of the copper busbar, so that the resin and the metal form a high-strength bond and achieve a dense bond, so that the bonding strength of the prepared injection-molded copper busbar is higher, thereby improving the performance of the copper busbar, and further improving the overall performance of the motor controller system, which helps to improve the stability and safety of the motor controller system during operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A flowchart of the steps of a method for preparing an injection-molded copper busbar provided in one embodiment of the present application;

[0014] Figure 2 This is a flow chart of the steps of electrolytic corrosion treatment of a copper busbar in one embodiment of the present application;

[0015] Figure 3 A flow chart of the steps of the injection molding process provided in one embodiment of the present application;

[0016] Figure 4 A schematic diagram of a broken line showing bonding strength in a durability test provided by an embodiment of the present application;

[0017] Figure 5 A schematic diagram of a curve of bonding strength in an aging test provided in an embodiment of the present application. DETAILED DESCRIPTION

[0018] The embodiments of the present application are further described in detail below in conjunction with the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are only used to explain the embodiments of the present application, rather than to limit the embodiments of the present application. It should also be noted that, for ease of description, only the parts related to the embodiments of the present application rather than all structures are shown in the accompanying drawings, and those skilled in the art should be able to think of it after reading the specification of this application that as long as the technical features do not contradict each other, any combination of the technical features can constitute an optional implementation method.

[0019] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable when appropriate, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are generally a class, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally represents that the objects associated before and after are in an "or" relationship. In the description of the present application, "multiple" means two or more, and "several" means one or more.

[0020] In new energy vehicles, the motor controller system is one of the core parts. The motor controller system is used to convert the direct current of the battery into the alternating current required by the motor to drive the motor. For the motor controller, the design of the high-pressure injection molded copper busbar and the through-cylinder sealing structure is crucial. The high-pressure injection molded copper busbar is a key component in the motor controller system. It is responsible for the transmission of large currents, and its performance directly affects the efficiency and reliability of the motor controller system. The through-cylinder sealing structure is to prevent electrical connection between the inside of the motor controller system and the external environment, and to ensure the safety and stability of the motor controller system. For this reason, the reliability and stability of the high-pressure injection molded copper busbar and the through-cylinder sealing structure must be high enough to cope with the application scenario of high-power vehicle operation.

[0021] There is a method provided in the related art, such as setting a glue filling groove on the design of the injection-molded copper busbar, and then sealing the glue filling groove with glue in the subsequent process to achieve sealing. However, there are many factors that cause quality problems in the production of glue, such as the mixing accuracy of two-component glue, mixing time, storage time, curing conditions, performance stability after filling, etc., which are very easy to cause sealing failure. Another method is to wet the injection-molded copper busbar with glue in advance, and then seal it by fixing and squeezing the wet glue through the plastic-coated copper busbar bolts. This method requires control of the amount of glue, and the glue will appear after extrusion. It is not conducive to simple installation and has certain restrictions on the structural space layout in the electric drive system. In addition, the bonding strength of the injection-molded copper busbar formed by the above method is poor. In performance tests such as durability tests and aging tests, its bonding strength is poor, and it is easy to fall off, which has an adverse effect on the stable operation of the motor controller system.

[0022] In this regard, the present application provides a method for preparing an injection molded copper busbar, such as Figure 1 As shown, Figure 1A flowchart of a method for preparing an injection-molded copper busbar provided in one embodiment of the present application. In one embodiment, the present solution processes the surface of the copper busbar by utilizing an electrolytic corrosion reaction to form a pit, and then uses an injection mold to perform high-pressure injection molding in a subsequent process to form an injection-molded copper busbar. The specific steps are as follows:

[0023] Step S110: Corrosion treatment is performed on the copper busbar to be prepared in an electrolytic cell to form pits on the surface of the copper busbar.

[0024] Before the preparation process, a suitable copper bar is selected as the copper bar to be prepared. It is conceivable that the material of the copper bar includes pure copper. Optionally, pure copper is used as the material of the copper bar in one embodiment. The prepared injection molded copper bar needs to be treated with electrolytic corrosion to facilitate better injection molding. In some embodiments, the copper bar is electrolyzed by using an electrolytic cell. It is conceivable that an electrolyte is injected into the electrolytic cell, and the copper bar placed in the electrolytic cell is corroded by the electrolyte in the electrolytic cell so that pits are formed on the surface of the copper bar. It is understandable that the electrolytic corrosion effect of the copper bar can be controlled by adjusting the electrolytic parameters such as temperature, voltage, and electrolysis time, so that the pits formed on the surface of the copper bar can meet the preparation requirements. It should be noted that the shape, size, etc. of the electrolytic cell in this scheme can meet the placement space requirements of a batch of copper bars to be prepared according to actual use requirements.

[0025] Figure 2 This is a flow chart of the steps of electrolytic corrosion treatment of the copper busbar in one embodiment of the present application. In this scheme, the copper busbar is treated by an electrolytic cell, and the temperature, voltage, electrolysis time and other conditions of the electrolytic cell are adjusted to achieve electrolytic corrosion of the copper busbar. Figure 2 As shown, the electrolytic corrosion treatment includes steps S210 to S220:

[0026] Step S210: adjusting the temperature in the electrolytic cell to a first temperature range, and controlling the voltage of the electrolytic cell to maintain within a preset voltage range.

[0027] Step S220: According to a preset electrolysis time, the surface of the copper busbar is corroded by the electrolyte in the electrolytic cell to form nano-scale pits on the surface of the copper busbar. The electrolysis time is 30-35 minutes.

[0028] It is understandable that the electrolytic cell is an important equipment in industrial production, and its temperature control is crucial to ensure the efficiency and safety of the electrolytic process. The temperature control of the working temperature of the electrolytic cell also involves many aspects, such as the use of refractory bricks for thermal insulation and optimization of the design of the heat dissipation area, etc., to ensure the stability of the electrolytic process and the safety of the working environment. In this regard, the working temperature of the electrolytic cell is adjusted to a first temperature range, the value of which is greater than or equal to 55°C and less than or equal to 65°C, for example, by means of heating by powering on a heater, radiant heat transfer, etc. to increase the working temperature.

[0029] In one embodiment, the electrolytic cell is powered on and heated by a heater to heat the electrolyte therein, and the operating temperature is heated to 60°C. It is conceivable that in order to avoid energy waste, appropriate insulation measures such as configuring a constant temperature device are taken to keep the temperature of the electrolytic cell constant, such as detecting the current temperature by a thermostat, and starting the constant temperature heater according to the corresponding constant temperature control algorithm. In addition, for the corresponding constant temperature control algorithm, the algorithm in the relevant technology is used to achieve constant temperature control, which is not limited. It should be noted that in some embodiments, the operating temperature can also be 55°C or 65°C, and the specific temperature selection is set according to the actual use requirements. In addition, similarly, the electrolytic cell can also be powered on and heated by a heater to heat the electrolyte therein so that the operating temperature reaches 55°C or 65°C.

[0030] When using the electrolytic cell, electrolysis is performed by controlling parameters such as the voltage or current of the electrolytic cell. For example, the voltage of the electrolytic cell is controlled to facilitate electrolytic corrosion. To this end, the voltage of the electrolytic cell is maintained within a preset voltage range, and the value of the preset voltage range is greater than or equal to 8V and less than or equal to 12V. In one embodiment, direct current can be used for electrolysis, such as providing 8V direct current so that the voltage of the electrolytic cell can reach 8V, and then the copper busbar is electrolyzed to form pits on the surface of the copper busbar.

[0031] In one embodiment, direct current is used to power the electrolytic cell. In this solution, the voltage of the electrolytic cell is maintained at 10V. The voltage of 10V provides a wider voltage window, so that the electrolysis process can be carried out stably at a higher voltage, thereby ensuring the thoroughness and safety of the electrolysis, helping to improve the thoroughness of the electrolysis and also improving the efficiency of the electrolysis. It should be noted that in some embodiments, the voltage parameter of the electrolytic cell can also be 12V, thereby providing a wider voltage window for the electrolysis process, which is conducive to the electrolysis process being able to be carried out stably at a higher voltage, making the electrolysis more thorough.

[0032] Then, according to the preset electrolysis time, the copper bar is subjected to electrolytic corrosion treatment using an electrolytic cell, such as starting the electrolytic corrosion treatment for 30-35 minutes, that is, the electrolysis time is greater than or equal to 30 minutes and less than or equal to 35 minutes, and the electrolyte is used as the electrolyte of the electrolysis process. During the electrolysis process, the surface of the copper bar can react with the electrolyte, so that the surface of the copper bar is corroded to form nano-scale pits. Preferably, in one embodiment, after 30 minutes of electrolysis, the surface of the copper bar can be corroded to form tiny pits, and the pits thereon can reach the nanometer level, which is helpful for better high-pressure injection molding and improving the bonding strength of the injection-molded copper bar.

[0033] It can be imagined that in one embodiment, the electrolysis time is set to 35 minutes. Through a longer electrolysis time, the surface of the copper busbar can be better corroded to form pits, which helps the formation of pits, so that the bonding strength of the injection-molded copper busbar is improved.

[0034] In this regard, by adjusting the electrolytic parameters of the electrolytic cell to perform electrolytic corrosion treatment on the copper busbar using an electrolyte in the electrolytic cell, this solution can utilize the electrolytic corrosion reaction to treat the surface of the copper busbar, so that pits are formed on the surface of the copper busbar, thereby helping to improve the bonding strength of the injection-molded copper busbar.

[0035] In one embodiment, the electrolyte includes a sodium hydroxide solution. As a common inorganic compound, sodium hydroxide can be used as an electrolyte in the electrolysis process. In the anode reaction, the sodium hydroxide solution can decompose sodium hydroxide ions, including hydrogen ions and oxygen ions, thereby accelerating the electrolysis process. That is, the electrolyte including the sodium hydroxide solution can accelerate the electrolysis rate and help shorten the process time. It should be noted that in some embodiments, the electrolyte used includes a copper sulfate solution and / or a copper nitrate solution to enhance the conductivity of the electrolyte.

[0036] Step S120: using a cleaning agent to clean the copper busbar after the corrosion treatment.

[0037] After the electrolytic corrosion treatment is completed, the copper bar is removed from the electrolytic tank. Accordingly, the copper bar after the corrosion treatment needs to be cleaned to remove the residual electrolyte thereon, such as using a cleaning agent to clean the copper bar to clean the surface of the copper bar again to prevent the residual electrolyte on the surface of the copper bar from affecting the subsequent process steps. For example, in one embodiment, after the copper bar after the corrosion treatment is taken out of the electrolyte, it is rinsed with clean water to remove the electrolyte on the surface of the copper bar.

[0038] Exemplarily, the electrolyte used in the electrolytic cell includes a sodium hydroxide solution, and accordingly, clean water can be used as a cleaning agent for rinsing. While diluting the electrolyte, the electrolyte remaining on the surface of the copper bar can also be removed by rinsing. It is conceivable that in the case where the electrolyte includes a sodium hydroxide solution, in some embodiments, a cleaning agent including a copper sulfate solution can also be used for cleaning, so as to better remove the sodium hydroxide solution by utilizing the reaction of copper sulfate and sodium hydroxide, so that the rinsing effect of the electrolyte is better.

[0039] Step S130 , baking the copper busbar at a preset temperature for a preset time to solidify the pits formed on the surface of the copper busbar.

[0040] After removing the residual electrolyte on the copper busbar, the copper busbar needs to be baked, such as baking at a preset temperature for a preset time, such as adjusting the baking temperature to a second temperature range, the value of the second temperature range is greater than or equal to 75°C and less than or equal to 85°C, so as to make the surface of the copper busbar more compact by using temperature changes. The baking time is greater than or equal to 120 minutes and less than or equal to 130 minutes, so as to solidify the pits formed on the surface of the copper busbar through long-term baking.

[0041] Optionally, in one embodiment, a drying machine is used to dry the copper bar, such as after cleaning the copper bar, transferring it to the drying machine, and adjusting the temperature parameters of the drying machine so that the temperature is adjusted to a preset temperature, such as maintaining the baking temperature at 80°C, so as to bake the copper bar under the corresponding temperature conditions (i.e., the baking temperature is 80°C). It should be noted that in some embodiments, the baking temperature can also be 75°C or 85°C, and the selection of the specific temperature is set according to the actual use requirements. And the corresponding baking time needs to reach a preset time, such as 120 minutes, and the baking treatment of the copper bar is ended after baking for 120 minutes. In this regard, while drying the surface moisture of the copper bar, the density of the copper bar surface can also be changed by high-temperature baking, thereby solidifying the pits formed on the surface of the copper bar, making the pits more obvious. Of course, in some embodiments, the baking time can also be set to 130 minutes, so as to bake with a longer baking time, which helps to solidify the pits formed on the surface of the copper bar.

[0042] Step S140: Under preset temperature and pressure conditions, the copper busbar is subjected to high-pressure injection molding using resin in an injection mold to fill the pits on the surface of the copper busbar with resin and form an injection-molded copper busbar.

[0043] Pressure control and temperature control in the injection molding process are important links in the process. Specifically, the injection pressure directly affects the plasticization and product quality of plastics. As for the temperature in the injection molding process, the temperature that needs to be controlled in the injection molding process includes barrel temperature, nozzle temperature and mold temperature, wherein the barrel temperature and nozzle temperature are used to affect the plasticization and flow of plastics, and the mold temperature is used to affect the flow and cooling of plastics. That is, the barrel temperature and nozzle temperature will affect the fluidity of the molten material injected into the cavity of the mold, and the mold temperature has a greater impact on the intrinsic performance and apparent quality of the product. To this end, the corresponding temperature and pressure need to be adjusted in the injection molding process so that the injection molding process can be better injection molded. In addition, in the high-pressure injection molding process, in addition to using the injection mold for injection molding, resin is also injected in the process so that the pits on the surface of the copper bar in the formed injection molded copper bar can be filled with resin.

[0044] It can be seen from the above scheme that the preparation method of this scheme forms pits on the surface of the copper busbar by electrolytic corrosion, and injects resin into the nano-scale pits on the surface of the copper busbar, so that the resin and the metal form a high-strength bond and achieve a dense bond, so that the bonding strength of the prepared injection-molded copper busbar is higher, thereby improving the performance of the copper busbar, and then improving the overall performance of the motor controller system, which helps to maintain the stability and safety of the motor controller system during operation.

[0045] Figure 3 A flowchart of the steps of the injection molding process provided in one embodiment of the present application. In one embodiment, the temperature and pressure of the injection molding process need to be adjusted to meet the preset temperature conditions and pressure conditions, and then the copper busbar is injection molded at the corresponding temperature and pressure, specifically including steps S310-S320:

[0046] Step S310: Control the mold temperature of the injection mold to be maintained within a third temperature range, and adjust the injection pressure of the injection molding equipment to a preset pressure range.

[0047] Step S320: The copper busbar is subjected to high-pressure injection molding for 10 minutes, and resin is added during the molding process to fill the pits on the surface of the copper busbar with resin.

[0048] It is understandable that the temperature of the injection mold is adjusted before injection molding so that the mold temperature reaches a third temperature range, the value of the third preset temperature range is greater than or equal to 190°C and less than or equal to 210°C, and the mold temperature is maintained at a corresponding temperature during the injection molding process. Optionally, in one embodiment, heat conduction is used, such as conducting heat to the mold surface through a medium (such as water, steam, etc.) in the internal pipe of the mold to increase the mold temperature; in another optional embodiment, heat radiation can be used, such as using solar energy, laser beams, etc. to radiate on the surface of the injection mold so that the mold temperature reaches the required level.

[0049] In one embodiment, the mold temperature is set to 200°C. Accordingly, the mold temperature can be raised to 200°C by heat conduction to make the plastic have better fluidity for injection molding. Of course, in some embodiments, the mold temperature can also be 190°C or 210°C, and the specific temperature can be set according to application requirements. Accordingly, the injection molding pressure used in the injection molding process is adjusted to a preset pressure range, and the value of the preset pressure range is greater than or equal to 9.8MPa and less than or equal to 10.2MPa. In this regard, in some embodiments, 9.8MPa or 10.2MPa is selected as the injection molding pressure to facilitate the injection molding of the injection molded copper busbar.

[0050] In one embodiment, the mold temperature used is 200°C and the injection pressure is 10MPa. After reaching the corresponding temperature and pressure conditions, that is, the mold temperature reaches 200°C and the injection pressure reaches 10MPa, the copper bar is subjected to high-pressure injection molding. In addition, resin is added in the process, for example, before starting the injection molding, so that the resin can be filled on the surface of the copper bar, thereby improving the bonding strength.

[0051] For example, in some embodiments, the resin injected during the injection molding process is a crystalline resin, such as a crystalline resin NMT (Nano Molding Technology) resin injected into the injection mold. It should be noted that in some embodiments, the resin used can also be a thermosetting resin, such as epoxy resin, polyester resin, etc.

[0052] Therefore, the copper bar is combined with the plastic to form an injection-molded copper bar by high-pressure injection molding. A pit is formed on the surface of the copper bar, and resin is injected to fill the pit, which can help improve the bonding strength between the copper bar and the plastic during the injection molding process.

[0053] In some embodiments, before the copper busbar is subjected to electrolytic corrosion treatment, the copper busbar may be ground, for example, the surface of the copper busbar may be processed by mechanical grinding, thereby forming a reinforcement structure on the surface of the copper busbar. The reinforcement structure is used to increase the bonding strength of the plastic, which helps to bond the copper busbar to the plastic during the subsequent injection molding process, thereby improving the bonding strength of the formed injection-molded copper busbar.

[0054] It should be noted that, in some embodiments, the reinforcement structure formed on the surface of the copper bar is a knurling pattern or an anti-slip groove, which can increase the bonding area between the copper bar and the plastic on the surface of the copper bar, thereby helping to improve the bonding strength of the injection-molded copper bar. It is conceivable that the position of the reinforcing structure ground on the surface of the copper bar can be set according to application requirements, such as being set at the edge area or the center area of ​​the copper bar.

[0055] The present application also provides an injection-molded copper busbar, which is prepared by the above-mentioned method for preparing the injection-molded copper busbar. The injection-molded copper busbar prepared by the above-mentioned method has high bonding strength, which makes the injection-molded copper busbar more stable, and helps to improve the stability and safety of the motor controller system during operation.

[0056] Exemplarily, in one embodiment, pits need to be formed on the surface of the copper busbar, and the surface of the copper busbar can be treated by utilizing an electrolytic corrosion reaction. Before the preparation process, a suitable copper busbar is selected as the copper busbar to be prepared, and an electrolyte, such as an electrolyte including a sodium hydroxide solution, is injected into the electrolytic cell, and the copper busbar placed in the electrolytic cell is corroded by the electrolyte in the electrolytic cell, such as adjusting the temperature of the electrolytic cell to 60°C, and controlling the voltage of the electrolytic cell to be maintained at 10V for electrolysis, and accordingly, the electrolysis time is 30 minutes to electrolytically corrode the surface of the copper busbar, so that pits are formed on the surface of the copper busbar.

[0057] After the electrolytic corrosion is completed, the copper bar is rinsed with a cleaning agent, such as water, to dilute and remove the residual electrolyte on the surface of the copper bar. After the copper bar is cleaned, it is baked, such as using a dryer to bake the copper bar. Specifically, the baking temperature is controlled to be maintained at 80°C and the baking is continued for 120 minutes, so that the moisture on the surface of the copper bar is dried, and the density of the copper bar surface can be changed by high-temperature baking, thereby solidifying the pits formed on the surface of the copper bar, making the pits more obvious.

[0058] For the injection molding process, the mold temperature of the injection mold is controlled to be maintained at 200°C, and the injection pressure of the injection molding equipment is adjusted to 10MPa, and then the copper busbar is subjected to high-pressure injection molding for 10 minutes. Resin is added during the process, such as before the injection molding, so that the resin can be filled on the surface of the copper busbar.

[0059] The injection molded copper busbar formed by the above method has high bonding strength. Figure 4 As shown, Figure 4 This is a schematic diagram of the broken line of the bonding strength in the durability test provided by an embodiment of the present application. The injection-molded copper busbar prepared by the present solution and the injection-molded copper busbar prepared by the related technology are subjected to a durability test. For example, in a cold and hot cycle durability test at -40°C, 30min (minutes) to 150°C, 30min (minutes), the bonding strength of the two is shown in the figure. Figure 4 The horizontal axis represents the number of cycles (in times), and the vertical axis represents the bonding strength (in MPa). The broken line 401 corresponds to the bonding strength of the injection-molded copper busbar prepared by this solution, and the broken line 402 corresponds to the bonding strength of the injection-molded copper busbar prepared by the related technology. Figure 4It can be seen that the injection-molded copper busbar prepared by this solution has higher bonding strength and is more stable, which helps to improve the stability and safety of the motor controller system during operation.

[0060] and Figure 5 A curve diagram of bonding strength in an aging test provided in an embodiment of the present application is shown in the figure. Similarly, the injection-molded copper busbar prepared in the present solution and the injection-molded copper busbar prepared in the related technology are subjected to aging tests, such as high-temperature and high-humidity aging tests under the conditions of 85°C and 85% RH (Relative Humidity). The bonding strength of the two is shown in the figure. Figure 5 The horizontal axis represents the aging time (in h), and the vertical axis represents the bonding strength (in MPa). The broken line 501 corresponds to the bonding strength of the injection-molded copper busbar prepared in this solution, and the broken line 502 corresponds to the bonding strength of the injection-molded copper busbar prepared in the related art. Figure 5 It can be seen that the injection-molded copper busbar prepared by this solution has higher bonding strength and is more stable, which helps to improve the stability and safety of the motor controller system during operation.

[0061] It can be seen that the injection-molded copper busbar prepared by the preparation method of this scheme has higher bonding strength, and its good performance is reflected in the durability test and aging test. The high bonding strength of the injection-molded copper busbar prepared by this scheme can improve the performance of the copper busbar, thereby improving the overall performance of the motor controller system, and contributing to the stability and safety of the motor controller system during operation.

[0062] The present application also provides a motor controller, which includes the above-mentioned injection-molded copper busbar. The injection-molded copper busbar has high bonding strength, so that the stability and safety of the motor controller can be guaranteed during the operation of the motor controller, which is conducive to stable and safe operation of the system.

[0063] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0064] Note that the above are only preferred embodiments of the present application and the technical principles used. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present application. Therefore, although the present application is described in more detail through the above embodiments, the present application is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present application, and the scope of the present application is determined by the scope of the appended claims.

Claims

1. A method for preparing an injection-molded copper busbar, characterized in that: include: The copper busbar to be prepared is subjected to an etching treatment by an electrolytic cell to form pits on the surface of the copper busbar; Use a cleaning agent to clean the copper busbar after corrosion treatment; Baking the copper busbar at a preset temperature for a preset time to solidify the pits formed on the surface of the copper busbar; Under preset temperature and pressure conditions, the copper busbar is subjected to high-pressure injection molding using resin in an injection mold, so as to fill the pits on the surface of the copper busbar with the resin and form the injection-molded copper busbar.

2. The method for preparing the injection molded copper busbar according to claim 1, characterized in that: The method of corroding the copper busbar to be prepared by an electrolytic cell to form pits on the surface of the copper busbar comprises: The temperature in the electrolytic cell is adjusted to a first temperature range, and the voltage of the electrolytic cell is controlled to be maintained within a preset voltage range, wherein the value of the first temperature range is greater than or equal to 55° C. and less than or equal to 65° C., and the value of the preset voltage range is greater than or equal to 8V and less than or equal to 12V; According to the preset electrolysis time, the surface of the copper busbar is corroded by the electrolyte in the electrolytic cell to form nano-scale pits on the surface of the copper busbar. The electrolysis time is 30-35 minutes.

3. The method for preparing the injection molded copper busbar according to claim 2, characterized in that: The electrolyte includes a sodium hydroxide solution.

4. The method for preparing the injection molded copper busbar according to claim 1, characterized in that: The step of baking the copper busbar at a preset temperature and for a preset time to solidify the pits formed on the surface of the copper busbar comprises: Controlling the baking temperature to be maintained within a second temperature range to bake the copper busbar, wherein the value of the second temperature range is greater than or equal to 75° C. and less than or equal to 85° C.; When the baking time reaches 120-130 minutes, the baking treatment of the copper bar is finished.

5. The method for preparing the injection molded copper busbar according to claim 1, characterized in that: The method comprises: performing high-pressure injection molding on the copper busbar in an injection mold under preset temperature and pressure conditions, and injecting resin into the pits on the surface of the copper busbar during the high-pressure injection molding process to form the injection-molded copper busbar, comprising: Controlling the mold temperature of the injection mold to be maintained within a third temperature range, and adjusting the injection pressure of the injection molding equipment to a preset pressure range, wherein the value of the third temperature range is greater than or equal to 190° C. and less than or equal to 210° C., and the value of the preset pressure range is greater than or equal to 9.8 MPa and less than or equal to 10.2 MPa; The copper busbar is subjected to a high-pressure injection molding process for 10 minutes, and resin is added during the process to fill the pits on the surface of the copper busbar with resin.

6. The method for preparing the injection-molded copper busbar according to claim 5, characterized in that: The resin is a crystalline resin or a thermosetting resin.

7. The method for preparing an injection-molded copper busbar according to any one of claims 1 to 6, characterized in that: Before the copper busbar to be prepared is corroded by the electrolytic cell to form pits on the surface of the copper busbar, the method further comprises: Through a grinding process, a reinforcement structure for increasing the bonding strength of the plastic is formed on the surface of the copper busbar.

8. The method for preparing the injection-molded copper busbar according to claim 7, characterized in that: The reinforcement structure is a knurled pattern or an anti-slip groove.

9. An injection-molded copper busbar, characterized in that: The injection-molded copper busbar is prepared by the method for preparing the injection-molded copper busbar according to any one of claims 1 to 8.

10. A motor controller, characterized in that: The motor controller comprises the injection-molded copper busbar as claimed in claim 9.

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