Conductive bar, preparation method thereof, battery device and electric equipment

Abstract

The application provides a method for preparing an aluminum-copper gradient conductive row based on an additive manufacturing technology, a conductive row, a battery device and an electric equipment. The method comprises the following steps: providing a red copper plate, a pure aluminum welding wire and a pure copper welding wire, taking the red copper plate as a welding base, taking the pure aluminum welding wire as an aluminum welding layer and taking the pure copper welding wire as a copper welding layer; slicing and parameter setting are performed on a three-dimensional model deposition path of the conductive row; according to the set parameters, an electric arc additive cladding is performed on the red copper plate by using a cold metal transition additive manufacturing system, so that a thin-wall structure of the conductive row suitable for a power lead-out device of a battery module is obtained, and the thin-wall structure comprises the aluminum welding layer, the copper welding layer and the welding base which are sequentially stacked from top to bottom; and the thin-wall structure is trimmed according to the requirement of the battery module, so that the required conductive row is obtained.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to a method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology, the conductive busbars, battery devices, and electrical equipment. Background Technology

[0002] The lead-out overlap of the conductive busbars in existing battery modules is typically fabricated using aluminum-nickel composite materials. However, existing conductive busbars and their fabrication methods have the following drawbacks: the overlap between the conductive busbar and the copper busbar is formed by a combination of three different materials, which will lead to electrochemical corrosion, accelerating the corrosion of the aluminum substrate and causing contact failure. Furthermore, the composite nickel layer / nickel sheet with the aluminum substrate using polymer diffusion welding technology cannot achieve effective metallurgical bonding, thus offering very limited improvement to the strength and hardness of the aluminum substrate. Moreover, the composite nickel layer / nickel sheet on the aluminum substrate surface will reduce the current carrying capacity of the aluminum substrate itself and also reduce its heat dissipation capacity. Summary of the Invention

[0003] A primary objective of this invention is to overcome at least one of the deficiencies of the prior art and provide a method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology, which can alleviate electrochemical corrosion problems, improve hardness and strength, improve conductivity, and improve heat dissipation.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] According to one aspect of the present invention, a method for preparing an aluminum-copper gradient busbar based on additive manufacturing technology is provided, comprising: providing a copper plate, pure aluminum welding wire, and pure copper welding wire, using the copper plate as a welding substrate, the pure aluminum welding wire as an aluminum welding layer, and the pure copper welding wire as a copper welding layer; slicing and setting parameters for the deposition path of a three-dimensional model of the busbar; according to the set parameters, using a cold metal transition additive manufacturing system to perform arc additive welding on the copper plate to obtain a thin-walled structure of the busbar suitable for a power lead-out device of a battery module, the thin-walled structure comprising an aluminum welding layer, a copper welding layer, and a welding substrate stacked sequentially from top to bottom; and modifying the thin-walled structure according to the requirements of the battery module to obtain the desired busbar.

[0006] According to one embodiment of the present invention, the step of providing a copper plate includes: removing stains from the surface of the copper plate; and placing the cleaned copper plate into a heating device for preheating treatment.

[0007] According to one embodiment of the present invention, the step of removing stains from the surface of the copper plate includes: mechanically polishing the surface of the copper plate; and immersing the copper plate in an ultrasonic instrument for cleaning with anhydrous ethanol.

[0008] According to one embodiment of the present invention, in the anhydrous ethanol cleaning step, the cleaning time is 35 min to 60 min.

[0009] According to one embodiment of the present invention, in the preheating treatment step: the heating device is a vacuum box furnace; and / or, the preheating temperature is 520°C to 650°C; and / or, the preheating time is 1.5h to 3h.

[0010] According to one embodiment of the present invention, the copper plate is a T2-Y pure copper plate; and / or the copper plate has a size of (100mm~300mm)×(100mm~300mm)×(5mm~10mm).

[0011] According to one embodiment of the present invention, the step of providing pure aluminum welding wire includes surface treatment of the pure aluminum welding wire.

[0012] According to one embodiment of the present invention, the step of surface treatment of pure aluminum welding wire includes: wiping the pure aluminum welding wire with anhydrous ethanol, and then drying the pure aluminum welding wire at a temperature of 55°C to 75°C.

[0013] According to one embodiment of the present invention, the step of providing pure copper welding wire includes surface treatment of the pure copper welding wire.

[0014] According to one embodiment of the present invention, the step of surface treatment of pure copper welding wire includes: wiping the pure copper welding wire with anhydrous ethanol, and then drying the pure copper welding wire at a temperature of 55°C to 75°C.

[0015] According to one embodiment of the present invention, the pure aluminum welding wire is ER1070 welding wire; and / or, the pure copper welding wire is S201 welding wire.

[0016] According to one embodiment of the present invention, the height ratio of the aluminum welding layer, the copper welding layer and the welding substrate is 16:16:1.

[0017] According to one embodiment of the present invention, in the arc additive welding step, the process parameters for welding the copper side are: welding current of 125A to 140A, welding voltage of 10V to 14V, welding speed of 0.15m / min to 0.35m / min, shielding gas of 99.99% argon by volume, shielding gas flow rate of 15L / min, wire feed speed of 4m / min to 6m / min, and wire extension length of 15mm to 20mm; and / or, in the arc additive welding step, the process parameters for welding the aluminum side are: welding current of 75A to 90A, welding voltage of 8V to 11V, welding speed of 0.15m / min to 0.35m / min, shielding gas of 99.99% argon by volume, shielding gas flow rate of 15L / min, wire feed speed of 1m / min to 1.5m / min, and wire extension length of 20mm to 25mm.

[0018] According to one embodiment of the present invention, in the arc additive welding step, the interlayer cooling time on the copper side is 1 min to 1.5 min, the interlayer cooling time on the aluminum side is 1.5 min to 2 min, the interlayer cooling temperature is 80°C to 120°C, and the cooling temperature of the last copper layer is 300°C to 400°C.

[0019] As can be seen from the above technical solution, the advantages and positive effects of the method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology proposed in this invention are as follows:

[0020] This invention proposes a method for preparing aluminum-copper gradient busbars using additive manufacturing technology, which can alleviate the electrochemical corrosion problem that occurs when copper and aluminum are bonded together in an atmospheric environment. Furthermore, this invention can improve the hardness and strength of the aluminum substrate, preventing locking deformation during secondary assembly of the busbar. Moreover, this invention can increase the conductivity and heat dissipation capacity of the aluminum substrate, improving the material's current-carrying capacity while preventing localized heat accumulation that could lead to safety accidents. In addition, this invention can significantly reduce material preparation costs and improve the manufacturability and processability of aluminum-copper composite materials.

[0021] Another major objective of this invention is to overcome at least one of the defects of the prior art described above and to provide a conductive busbar prepared by the above-described preparation method.

[0022] To achieve the above objectives, the present invention adopts the following technical solution:

[0023] According to another aspect of the present invention, a conductive bus is provided for electrically connecting two adjacent battery modules via a copper bus, wherein the conductive bus is prepared by the method for preparing an aluminum-copper gradient conductive bus based on additive manufacturing technology proposed in the present invention and described in the above embodiments.

[0024] Another major objective of this invention is to overcome at least one of the defects of the prior art and provide a conductive busbar with better hardness and strength, better conductivity and heat dissipation.

[0025] To achieve the above objectives, the present invention adopts the following technical solution:

[0026] According to another aspect of the present invention, a conductive bus is provided for electrically connecting two adjacent battery modules via a copper busbar. The conductive busbar includes a lead-out portion, a connecting portion, and a lap portion. The connecting portion has an upper end and a lower end. The lead-out portion is connected to one of the upper and lower ends of the connecting portion and is used to connect a terminal post of one of the battery modules. The lap portion is connected to the other of the upper and lower ends of the connecting portion and is used to connect the copper busbar and, via the copper busbar, connect another battery module. The lead-out portion and the lap portion are bent towards opposite sides relative to the connecting portion. The lead-out portion is made of an aluminum-copper composite material or aluminum, the connecting portion is made of an aluminum-copper composite material or copper, and the lap portion is made of copper. The conductive busbar is fabricated using an aluminum-copper gradient fabrication process based on additive manufacturing technology.

[0027] As can be seen from the above technical solution, the advantages and positive effects of the conductive bus proposed in this invention are as follows:

[0028] The conductive bus proposed in this invention can avoid the effects of electrochemical corrosion caused by atmospheric environment. Furthermore, the conductive bus proposed in this invention can avoid locking deformation during secondary assembly and can also avoid local heat accumulation that could cause safety accidents.

[0029] Another major objective of the present invention is to overcome at least one of the defects of the prior art described above and to provide a battery device employing the aforementioned conductive busbar.

[0030] To achieve the above objectives, the present invention adopts the following technical solution:

[0031] According to another aspect of the present invention, a battery device is provided, wherein the conductive busbar described in the present invention is included.

[0032] As can be seen from the above technical solution, the advantages and positive effects of the battery device proposed in this invention are as follows:

[0033] The battery device proposed in this invention, by employing the conductive busbar proposed in this invention, can avoid the impact of electrochemical corrosion caused by atmospheric environment, can avoid locking deformation of conductive busbar during secondary assembly, and can also avoid safety accidents caused by local heat accumulation of conductive busbar.

[0034] Another major objective of the present invention is to overcome at least one of the defects of the prior art described above and to provide an electrical device employing the battery device described above.

[0035] To achieve the above objectives, the present invention adopts the following technical solution:

[0036] According to another aspect of the present invention, an electrical device is provided, wherein the battery device described herein is included.

[0037] As can be seen from the above technical solution, the advantages and positive effects of the electrical equipment proposed in this invention are as follows:

[0038] The electrical equipment proposed in this invention, by adopting the battery device proposed in this invention, can avoid the electrochemical corrosion of the conductive busbar caused by the atmospheric environment, and can also avoid the locking deformation of the conductive busbar during secondary assembly, as well as the safety accidents caused by local heat accumulation in the conductive busbar. Attached Figure Description

[0039] Various objects, features, and advantages of the invention will become more apparent from the following detailed description of preferred embodiments of the invention, taken in conjunction with the accompanying drawings. The drawings are merely illustrative of the invention and are not necessarily drawn to scale. In the drawings, the same reference numerals always denote the same or similar parts. Wherein:

[0040] Figure 1 This is a schematic flowchart illustrating a method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to an exemplary embodiment.

[0041] Figure 2 yes Figure 1 A schematic diagram of the three-dimensional structure of the conductive busbar at a certain step of the preparation method is shown.

[0042] Figure 3 yes Figure 2 Side view;

[0043] Figure 4 Is adopted Figure 1 A schematic diagram of the metallographic structure at the transition interface of the conductive busbar prepared by the shown method.

[0044] Figure 5 This is a three-dimensional structural schematic diagram of a conductive bus according to an exemplary embodiment.

[0045] The annotations in the attached figures are explained as follows:

[0046] 100. Welding base material;

[0047] 200. Aluminum weld layer;

[0048] 300. Copper solder layer;

[0049] 500. Conductive busbar;

[0050] 510. Introduction section;

[0051] 520. Connecting part;

[0052] 530. Overlap section;

[0053] L1. Length;

[0054] L2. Width;

[0055] L3. Length;

[0056] L4. Width;

[0057] H1. Height;

[0058] H2. Height;

[0059] H3. Height;

[0060] X. Height direction;

[0061] Y. Deposition direction. Detailed Implementation

[0062] Typical embodiments embodying the features and advantages of the present invention will be described in detail in the following description. It should be understood that the present invention can have various variations in different embodiments without departing from the scope of the present invention, and the description and drawings therein are for illustrative purposes only and not intended to limit the present invention.

[0063] In the following description of different exemplary embodiments of the invention, reference is made to the accompanying drawings, which form part of the invention, and in which different exemplary structures, systems, and steps that can implement various aspects of the invention are shown by way of example. It should be understood that other specific embodiments of the components, structures, exemplary devices, systems, and steps may be used, and structural and functional modifications may be made without departing from the scope of the invention. Furthermore, although the terms “above,” “between,” “within,” etc., may be used in this specification to describe different exemplary features and elements of the invention, these terms are used herein only for convenience, such as the orientation according to the examples shown in the drawings. Nothing in this specification should be construed as requiring a specific three-dimensional orientation of the structure to fall within the scope of the invention.

[0064] See Figure 1This illustration represents a flowchart of the method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology proposed in this invention. In this exemplary embodiment, the method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology is described using a conductive busbar applied to a lithium battery as an example. It will be readily understood by those skilled in the art that various modifications, additions, substitutions, deletions, or other changes may be made to the specific embodiments described below to apply the relevant designs of this invention to other types of battery devices; these changes remain within the scope of the principles of the method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology proposed in this invention.

[0065] like Figure 1 As shown, in one embodiment of the present invention, the method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology proposed in the present invention includes:

[0066] It provides copper plates, pure aluminum welding wire and pure copper welding wire, with copper plates as the welding base 100, pure aluminum welding wire as the aluminum welding layer 200, and pure copper welding wire as the copper welding layer 300.

[0067] The deposition path of the 3D model of the conductive bus is sliced ​​and parameters are set;

[0068] According to the set parameters, the copper plate is subjected to arc additive welding using a cold metal transition additive manufacturing system (CMT-Advanced) to obtain a thin-walled structure of a conductive busbar suitable for the power lead-out device of the battery module. The thin-walled structure includes an aluminum welding layer 200, a copper welding layer 300 and a welding substrate 100 stacked from top to bottom.

[0069] The thin-walled structure is modified according to the requirements of the battery module to obtain the required conductive busbar.

[0070] Through the above design, the method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology proposed in this invention has at least the following beneficial effects:

[0071] The conductive bus prepared by this invention can significantly reduce the electrochemical corrosion problem caused by the combination of copper and aluminum in the atmospheric environment. Specifically, although the potential difference between aluminum (Al, -1.662V) and copper (Cu, 0.3419V) is large, the CMT additive manufacturing method can achieve a continuous gradient transition from copper to aluminum structure. The resulting metallographic transition region has no obvious interface and is a copper-aluminum alloy structure. Therefore, it can reduce the tendency of electrochemical corrosion caused by the combination of copper and aluminum in the atmospheric environment. For details, please refer to [the relevant documentation]. Figure 4 A schematic diagram of the metallographic structure at the transition interface of the conductive busbar is shown.

[0072] The conductive busbar prepared by this invention can significantly improve the hardness and strength of the aluminum substrate, avoiding locking deformation during secondary assembly of components. Specifically, the copper-aluminum gradient conductive busbar has a hardness of 73.7HV0.1 and a tensile strength of 148.5MPa, which is much greater than that of the aluminum conductive busbar (hardness of 43HV0.1 and strength of 120MPa).

[0073] The conductive bus prepared by this invention can significantly increase the conductivity of the aluminum substrate and improve the current carrying capacity of the material (iron ≤ aluminum ≤ gold ≤ copper ≤ silver). Specifically, the conductivity of common metals is in the following order: iron ≤ nickel ≤ aluminum ≤ gold ≤ copper ≤ silver, where the conductivity of copper is 59.594 S / m and the conductivity of aluminum is 37.667 S / m. Therefore, preparing a copper-aluminum gradient conductive bus will significantly improve the current carrying capacity of the aluminum substrate itself.

[0074] The conductive bus prepared by this invention can significantly improve the heat dissipation capacity of the aluminum substrate and avoid safety accidents caused by local heat accumulation. Specifically, the thermal conductivity of copper is 401 W / mK and that of aluminum is 237 W / mK. Therefore, the prepared copper-aluminum gradient conductive bus will significantly improve the heat dissipation capacity of the aluminum substrate itself.

[0075] The conductive busbar prepared by this invention can significantly reduce material preparation costs and improve the manufacturability and processability of copper-aluminum dissimilar composite materials. Specifically, the aluminum-nickel composite conductive busbars used in existing solutions involve nickel plating on the aluminum surface, which is costly. The copper-aluminum composite conductive busbar of this invention can significantly reduce costs and improve manufacturability and processability.

[0076] In one embodiment of the present invention, the step of providing the copper plate may further include: first removing stains from the surface of the copper plate, and then placing the cleaned copper plate into a heating device for preheating treatment. Through the above design, the present invention can ensure the surface cleanliness of the copper plate, avoid the impact of stains on the surface of the copper plate on the welding effect, and at the same time, utilize the preheated copper plate to improve its welding effect.

[0077] In one embodiment of the present invention, the step of removing stains from the surface of a copper plate may further include: first, mechanically polishing the surface of the copper plate, and then placing the copper plate into an ultrasonic cleaner for anhydrous ethanol cleaning. Through the above design, the present invention can remove rust and oil stains adhering to the surface of a copper plate using mechanical polishing, and can further remove stains from the surface of the copper plate using anhydrous ethanol cleaning in an ultrasonic cleaner.

[0078] In one embodiment of the present invention, in the anhydrous ethanol cleaning step, the cleaning time of the copper plate in the ultrasonic instrument with anhydrous ethanol can be 35 min to 60 min, for example, 35 min, 45 min, 50 min, 60 min, etc. In some embodiments, the cleaning time of the copper plate in the ultrasonic instrument with anhydrous ethanol can be shorter than 35 min, or longer than 60 min, for example, 34 min, 61 min, etc., and is not limited to this embodiment.

[0079] In one embodiment of the present invention, in the preheating step, the heating device may be a vacuum box furnace.

[0080] In one embodiment of the present invention, the temperature for preheating the copper plate in the preheating treatment step can be 520°C to 650°C, for example, 520°C, 550°C, 600°C, 650°C, etc. In some embodiments, the temperature for preheating the copper plate can be lower than 520°C or higher than 650°C, for example, 510°C, 660°C, etc., and is not limited to this embodiment.

[0081] In one embodiment of the present invention, the preheating time for the copper plate in the preheating treatment step can be 1.5h to 3h, for example, 1.5h, 2h, 2.5h, 3h, etc. In some embodiments, the preheating time for the copper plate can be shorter than 1.5h or longer than 3h, for example, 1.4h, 3.1h, etc., and is not limited to this embodiment.

[0082] In one embodiment of the present invention, the copper plate can be a T2-Y pure copper plate.

[0083] like Figure 2 and Figure 3 As shown, in one embodiment of the present invention, the dimensions of the copper plate can be (100mm~300mm)×(100mm~300mm)×(5mm~10mm). In other words, the length L1 of the copper plate can be 100mm~300mm, the width L2 of the copper plate can be 100mm~300mm, and the height H1 of the copper plate can be 5mm~10mm. Furthermore, the length L1 and width L2 of the copper plate are preferably equal, that is, the copper plate can be approximately square. In some embodiments, the copper plate can also be rectangular, that is, the length L1 and width L2 of the copper plate are not equal, and this is not limited to this embodiment.

[0084] In one embodiment of the present invention, the step of providing pure aluminum welding wire may further include: performing surface treatment on the pure aluminum welding wire.

[0085] In one embodiment of the present invention, the step of surface treatment of pure aluminum welding wire may further include: first wiping the pure aluminum welding wire with anhydrous ethanol, and then drying the pure aluminum welding wire at a temperature of 55°C to 75°C.

[0086] In one embodiment of the present invention, the step of providing pure copper welding wire may further include: performing surface treatment on the pure copper welding wire.

[0087] In one embodiment of the present invention, the step of surface treatment of pure copper welding wire may further include: first wiping the pure copper welding wire with anhydrous ethanol, and then drying the pure copper welding wire at a temperature of 55°C to 75°C.

[0088] In one embodiment of the present invention, the pure aluminum welding wire can be ER1070 welding wire.

[0089] In one embodiment of the present invention, the pure copper welding wire can be S201 welding wire.

[0090] In one embodiment of the present invention, the height ratio of the aluminum welding layer 200, the copper welding layer 300, and the welding substrate 100 can be 16:16:1. Specifically, as... Figure 2 and Figure 3 As shown, taking the height H1 of the copper plate as 5mm as an example, that is, the height of the welding substrate 100 is 5mm. On this basis, the overall height H2 of the copper welding layer 300 (that is, the copper deposition layer deposited by stacking multiple layers of pure copper welding wire along the deposition direction Y) (that is, the overall height of the multi-layer structure in the height direction X) can be 80mm, and the overall height H3 of the aluminum welding layer 200 (that is, the aluminum deposition layer deposited by stacking multiple layers of pure aluminum welding wire along the deposition direction Y) (that is, the overall height of the multi-layer structure in the height direction X) can be 80mm.

[0091] In one embodiment of the present invention, in the step of arc additive welding, the process parameters for welding the copper side can be: welding current can be 125A to 140A, welding voltage can be 10V to 14V, welding speed can be 0.15m / min to 0.35m / min, shielding gas can be argon with a volume fraction of 99.99%, shielding gas flow rate can be 15L / min, wire feed speed can be 4m / min to 6m / min, and wire extension length can be 15mm to 20mm.

[0092] In one embodiment of the present invention, in the step of arc additive welding, the process parameters for welding the aluminum side can be: welding current can be 75A to 90A, welding voltage can be 8V to 11V, welding speed can be 0.15m / min to 0.35m / min, shielding gas can be argon with a volume fraction of 99.99%, shielding gas flow rate can be 15L / min, wire feed speed can be 1m / min to 1.5m / min, and wire extension length can be 20mm to 25mm.

[0093] In one embodiment of the present invention, in the step of arc additive welding, the interlayer cooling time on the copper side can be 1 min to 1.5 min, the interlayer cooling time on the aluminum side can be 1.5 min to 2 min, the interlayer cooling temperature can be 80°C to 120°C, and the cooling temperature of the last copper layer can be 300°C to 400°C.

[0094] Based on the above detailed description of the method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology proposed in this invention, the following will illustrate several specific embodiments that conform to the design concept of this preparation method. Specific Implementation Example 1

[0096] Step 1: First, mechanically grind the surface of the copper plate to remove rust and oil stains. Then, place it in an ultrasonic cleaner for anhydrous ethanol cleaning for 35 minutes to remove stains from the surface of the copper plate. Finally, place the treated copper plate in a vacuum box furnace for preheating treatment at a temperature of 520℃ for 1.5 hours.

[0097] In step 1, the copper plate is a T2-Y copper plate with dimensions of 100mm×100mm×5mm;

[0098] Step 2: Perform surface treatment on pure copper welding wire and pure aluminum welding wire, wipe with anhydrous ethanol cloth, and dry in a vacuum tube furnace at a drying temperature of 55℃.

[0099] In step 2, the pure aluminum welding wire is ER1070 welding wire, and the pure copper welding wire is S201 welding wire. The size of both the pure aluminum welding wire and the pure copper welding wire is φ1.2mm.

[0100] Step 3: Arc additive welding is performed using a cold metal transition additive manufacturing system. First, the deposition path of the 3D model of the copper / aluminum busbar is simulated by slicing using metal 3D printing software. This scheme adopts a single-pass reciprocating deposition modeling (a strategy of depositing copper first and then aluminum). The interlayer cooling time for the copper side is 1 min, and the interlayer cooling time for the aluminum side is 1.5 min. The interlayer cooling temperature is 80℃ for both sides (the cooling temperature of the last copper layer is 300℃~400℃). The specific welding parameters for the copper side are: welding current 125A, The welding voltage was 10V, the welding speed was 0.15m / min, the shielding gas was 99.99% argon gas with a flow rate of 15L / min, the wire feed speed was 4m / min, and the wire extension length was 15mm. The specific parameters for welding the aluminum side were: welding current 75A, welding voltage 8V, welding speed 0.15m / min, shielding gas was 99.99% argon gas with a flow rate of 15L / min, the wire feed speed was 1m / min, and the wire extension length was 20mm. Ultimately, a thin-walled copper / aluminum gradient composite conductive busbar structure suitable for the power lead-out device of a battery module was obtained.

[0101] The thin-walled conductive busbar structure prepared using the above-described specific embodiment 1, after mechanical property testing, has a tensile strength of 140.8 MPa and a micro Vickers hardness of 65.4 HV0.1. Furthermore, it exhibits minimal spatter during welding, good weld formation, and no cracks or slag inclusions in the wall structure. It is suitable for copper / aluminum gradient composite conductive busbars that have been finally machined and formed. Specific Implementation Example 2

[0103] Step 1: First, mechanically grind the surface of the copper plate to remove rust and oil stains. Then, place it in an ultrasonic cleaner for anhydrous ethanol cleaning for 35 minutes to remove stains from the surface of the copper plate. Finally, place the treated copper plate in a vacuum box furnace for preheating treatment at a temperature of 550℃ for 1.8 hours.

[0104] In step 1, the copper plate is a T2-Y copper plate with dimensions of 200mm×200mm×5mm;

[0105] Step 2: Perform surface treatment on pure copper welding wire and pure aluminum welding wire, wipe with anhydrous ethanol cloth, and dry in a vacuum tube furnace at a drying temperature of 60℃.

[0106] In step 2, the pure aluminum welding wire is ER1070 welding wire, and the pure copper welding wire is S201 welding wire. The size of both the pure aluminum welding wire and the pure copper welding wire is φ1.2mm.

[0107] Step 3: Arc additive welding is performed using a cold metal transition additive manufacturing system. First, the deposition path of the 3D model of the copper / aluminum busbar is simulated using metal 3D printing software. This scheme adopts a single-pass reciprocating deposition modeling (a strategy of depositing copper first and then aluminum). The interlayer cooling time for the copper side is 1.1 min, and the interlayer cooling time for the aluminum side is 1.6 min. The interlayer cooling temperature is 90℃ for both sides (the cooling temperature of the last copper layer is 350℃). The specific welding parameters for the copper side are: welding current 128A, welding current... The welding parameters for the aluminum side were as follows: welding voltage 11V, welding speed 0.20m / min, shielding gas 99.99% argon with a flow rate of 15L / min, wire feed speed 4.5m / min, and wire extension length 16mm. The specific parameters for the aluminum side welding process were: welding current 78A, welding voltage 9V, welding speed 0.20m / min, shielding gas 99.99% argon with a flow rate of 15L / min, wire feed speed 1.1m / min, and wire extension length 21mm. Ultimately, a thin-walled copper / aluminum gradient composite conductive busbar structure suitable for battery module power lead-out devices was obtained.

[0108] The thin-walled conductive busbar structure prepared using the above-described specific embodiment 2, after mechanical property testing, has a tensile strength of 145.1 MPa and a micro Vickers hardness of 68.9 HV0.1. Furthermore, it exhibits minimal spatter during welding, good weld formation, and no cracks or slag inclusions in the wall structure. It is suitable for copper / aluminum gradient composite conductive busbars that have been finally machined and formed. Specific Implementation Example 3

[0110] Step 1: First, mechanically grind the surface of the copper plate to remove rust and oil stains. Then, place it in an ultrasonic cleaner for anhydrous ethanol cleaning for 35 minutes to remove stains from the surface of the copper plate. Finally, place the treated copper plate in a vacuum box furnace for preheating treatment at a temperature of 580℃ for 2.1 hours.

[0111] In step 1, the copper plate is a T2-Y copper plate with dimensions of 100mm×100mm×5mm;

[0112] Step 2: Perform surface treatment on pure copper welding wire and pure aluminum welding wire, wipe with anhydrous ethanol cloth, and dry in a vacuum tube furnace at a temperature of 65°C.

[0113] In step 2, the pure aluminum welding wire is ER1070 welding wire, and the pure copper welding wire is S201 welding wire. The size of both the pure aluminum welding wire and the pure copper welding wire is φ1.2mm.

[0114] Step 3: Arc additive welding is performed using a cold metal transition additive manufacturing system. First, the deposition path of the 3D model of the copper / aluminum busbar is simulated using metal 3D printing software. This scheme adopts a single-pass reciprocating deposition modeling (a strategy of depositing copper first and then aluminum). The interlayer cooling time for the copper side is 1.2 min, and the interlayer cooling time for the aluminum side is 1.7 min. The interlayer cooling temperature is 100℃ for both sides (the cooling temperature of the last copper layer is 350℃). The specific welding parameters for the copper side are: welding current 132A, welding... The welding parameters for the aluminum side were as follows: voltage 12V, welding speed 0.25m / min, shielding gas 99.99% argon with a flow rate of 15L / min, wire feed speed 5m / min, and wire extension length 18mm. The specific parameters for the aluminum side welding process were: welding current 82A, welding voltage 10V, welding speed 0.25m / min, shielding gas 99.99% argon with a flow rate of 15L / min, wire feed speed 1.3m / min, and wire extension length 22mm. Ultimately, a thin-walled copper / aluminum gradient composite conductive busbar structure suitable for the module's power lead-out device was obtained.

[0115] The thin-walled conductive busbar structure prepared using the above-described specific embodiment 3, after mechanical property testing, has a tensile strength of 148.5 MPa and a micro Vickers hardness of 73.7 HV0.1. Furthermore, it exhibits minimal spatter during welding, good weld formation, and no cracks or slag inclusions in the wall structure. It is suitable for copper / aluminum gradient composite conductive busbars that have been finally machined and formed. Specific Implementation Example 4

[0117] Step 1: First, mechanically grind the surface of the copper plate to remove rust and oil stains. Then, place it in an ultrasonic cleaner for anhydrous ethanol cleaning for 35 minutes to remove stains from the surface of the copper plate. Finally, place the treated copper plate in a vacuum box furnace for preheating treatment at a temperature of 610℃ for 2.4 hours.

[0118] In step 1, the copper plate is a T2-Y copper plate with dimensions of 200mm×200mm×5mm;

[0119] Step 2: Perform surface treatment on pure copper welding wire and pure aluminum welding wire, wipe with anhydrous ethanol cloth, and dry in a vacuum tube furnace at a temperature of 70°C.

[0120] In step 2, the pure aluminum welding wire is ER1070 welding wire, and the pure copper welding wire is S201 welding wire. The size of both the pure aluminum welding wire and the pure copper welding wire is φ1.2mm.

[0121] Step 3: Arc additive welding is performed using a cold metal transition additive manufacturing system. First, the deposition path of the 3D model of the copper / aluminum busbar is simulated using metal 3D printing software. This scheme adopts a single-pass reciprocating deposition modeling (a strategy of depositing copper first and then aluminum). The interlayer cooling time for the copper side is 1.3 min, and the interlayer cooling time for the aluminum side is 1.8 min. The interlayer cooling temperature for both is 110℃ (the cooling temperature of the last copper layer is 350℃). The specific welding parameters for the copper side are: welding current 135A, welding current... The welding parameters for the aluminum side were as follows: welding voltage 13V, welding speed 0.30m / min, shielding gas 99.99% argon with a flow rate of 15L / min, wire feed speed 5.5m / min, and wire extension length 19mm. The specific parameters for the aluminum side welding process were: welding current 85A, welding voltage 10V, welding speed 0.30m / min, shielding gas 99.99% argon with a flow rate of 15L / min, wire feed speed 1.4m / min, and wire extension length 24mm. Ultimately, a thin-walled copper / aluminum gradient composite conductive busbar structure suitable for the module's power lead-out device was obtained.

[0122] The thin-walled conductive busbar structure prepared using the above-described specific embodiment 4, after mechanical property testing, has a tensile strength of 146.7 MPa and a micro Vickers hardness of 70.1 HV0.1. Furthermore, it exhibits minimal spatter during welding, good weld formation, and no cracks or slag inclusions in the wall structure. It is suitable for copper / aluminum gradient composite conductive busbars that have been finally machined and formed. Specific Implementation Example 5

[0124] Step 1: First, mechanically grind the surface of the copper plate to remove rust and oil stains. Then, place it in an ultrasonic cleaner for anhydrous ethanol cleaning for 35 minutes to remove stains from the surface of the copper plate. Finally, place the treated copper plate in a vacuum box furnace for preheating treatment at a temperature of 650℃ for 3 hours.

[0125] In step 1, the copper plate is a T2-Y copper plate with dimensions of 100mm×100mm×5mm;

[0126] Step 2: Perform surface treatment on pure copper welding wire and pure aluminum welding wire, wipe with anhydrous ethanol cloth, and dry in a vacuum tube furnace at a temperature of 75°C.

[0127] In step 2, the pure aluminum welding wire is ER1070 welding wire, and the pure copper welding wire is S201 welding wire. The size of both the pure aluminum welding wire and the pure copper welding wire is φ1.2mm.

[0128] Step 3: Arc additive welding is performed using a cold metal transition additive manufacturing system. First, the deposition path of the 3D model of the copper / aluminum busbar is simulated using metal 3D printing software. This scheme adopts a single-pass reciprocating deposition modeling (a strategy of depositing copper first and then aluminum). The interlayer cooling time for the copper side is 1.5 min, and the interlayer cooling time for the aluminum side is 2 min. The interlayer cooling temperature is 120℃ for both sides (the cooling temperature of the last copper layer is 350℃). The specific welding parameters for the copper side are: welding current 140A, welding current... The welding parameters for the aluminum side were as follows: welding voltage 14V, welding speed 0.35m / min, shielding gas 99.99% argon with a flow rate of 15L / min, wire feed speed 6m / min, and wire extension length 20mm. The specific parameters for the aluminum side welding process were: welding current 90A, welding voltage 11V, welding speed 0.35m / min, shielding gas 99.99% argon with a flow rate of 15L / min, wire feed speed 1.5m / min, and wire extension length 25mm. Ultimately, a thin-walled copper / aluminum gradient composite conductive busbar structure suitable for the module's power lead-out device was obtained.

[0129] The thin-walled conductive busbar structure prepared using the above-described specific embodiment 5, after mechanical property testing, has a tensile strength of 142.6 MPa and a micro Vickers hardness of 66.5 HV0.1. Furthermore, it exhibits minimal spatter during welding, good weld formation, and no cracks or slag inclusions in the wall structure. It is suitable for copper / aluminum gradient composite conductive busbars that have been finally machined and formed.

[0130] It should be noted that the methods for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology shown in the accompanying drawings and described in this specification are merely a few examples among many preparation methods that can employ the principles of the present invention. It should be clearly understood that the principles of the present invention are by no means limited to any details or steps of the methods for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology shown in the accompanying drawings or described in this specification.

[0131] In summary, the method for preparing aluminum-copper gradient busbars based on additive manufacturing technology proposed in this invention can alleviate the electrochemical corrosion problem that occurs in the atmospheric environment after copper and aluminum are combined. Furthermore, this invention can improve the hardness and strength of the aluminum matrix, avoiding locking deformation during secondary assembly of the busbar. Moreover, this invention can increase the conductivity and heat dissipation capacity of the aluminum matrix, improve the current carrying capacity of the material, and prevent localized heat accumulation that could lead to safety accidents. In addition, this invention can significantly reduce material preparation costs and improve the manufacturability and processability of aluminum-copper composite materials.

[0132] Based on the detailed description of several exemplary embodiments of the method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology proposed in this invention, several exemplary embodiments of the conductive busbars proposed in this invention will be described below.

[0133] like Figure 5 As shown, in one embodiment of the present invention, the conductive bus 500 proposed in the present invention is used to electrically connect two adjacent battery modules via a copper busbar. The conductive bus 500 is prepared by the method for preparing an aluminum-copper gradient conductive bus 500 based on additive manufacturing technology, as proposed in the present invention and described in detail in the above embodiment.

[0134] like Figure 5 As shown, in one embodiment of the present invention, the conductive bus 500 includes a lead-out portion 510, a connecting portion 520, and an overlapping portion 530. Specifically, the connecting portion 520 has an upper end and a lower end, the lead-out portion 510 is connected to one of the upper and lower ends of the connecting portion 520, and the lead-out portion 510 is used to connect to the terminal of a battery module. The overlapping portion 530 is connected to the other of the upper and lower ends of the connecting portion 520, and the overlapping portion 530 is used to connect to a copper busbar and connect to another battery module via the copper busbar. The lead-out portion 510 and the overlapping portion 530 are bent toward opposite sides relative to the connecting portion 520. For example, the conductive bus 500 including the lead-out portion 510, the connecting portion 520, and the overlapping portion 530 can be generally Z-shaped.

[0135] In some embodiments, the conductive bus proposed in this invention can also be prepared using other methods. The conductive bus includes a lead-out portion, a connecting portion, and a lap portion. The connecting portion has an upper end and a lower end. The lead-out portion is connected to one of the upper and lower ends of the connecting portion and is used to connect to the terminal post of a battery module. The lap portion is connected to the other of the upper and lower ends of the connecting portion and is used to connect to a copper busbar and, via the copper busbar, to another battery module. The lead-out portion and the lap portion are bent towards opposite sides relative to the connecting portion. Furthermore, the lead-out portion is made of an aluminum-copper composite material or aluminum, the connecting portion is made of an aluminum-copper composite material or copper, the lap portion is made of copper, and the conductive bus is prepared using an aluminum-copper gradient fabrication process based on additive manufacturing technology.

[0136] It should be noted that the conductive bus shown in the accompanying drawings and described in this specification are merely a few examples among many conductive buses from which the principles of the invention can be employed. It should be clearly understood that the principles of the invention are by no means limited to any detail or component of the conductive bus shown in the accompanying drawings or described in this specification.

[0137] In summary, the conductive bus proposed in this invention can avoid the effects of electrochemical corrosion caused by atmospheric environment. Furthermore, the conductive bus proposed in this invention can avoid locking deformation during secondary assembly and can also avoid safety accidents caused by local heat accumulation.

[0138] Based on the detailed description of several exemplary embodiments of the conductive bus proposed in this invention above, an exemplary embodiment of the battery device proposed in this invention will be described below.

[0139] In one embodiment of the present invention, the battery device proposed by the present invention includes the conductive bus proposed by the present invention and described in detail in the above embodiments.

[0140] It should be noted that the battery devices shown in the accompanying drawings and described in this specification are merely a few examples among many battery devices capable of employing the principles of the present invention. It should be clearly understood that the principles of the present invention are by no means limited to any detail or component of the battery devices shown in the accompanying drawings or described in this specification.

[0141] In summary, the battery device proposed in this invention, by employing the conductive busbar proposed in this invention, can avoid the impact of electrochemical corrosion caused by atmospheric environment, can avoid locking deformation of conductive busbar during secondary assembly, and can also avoid safety accidents caused by local heat accumulation of conductive busbar.

[0142] Based on the detailed description of several exemplary embodiments of the battery device proposed in this invention above, an exemplary embodiment of the electrical device proposed in this invention will be described below.

[0143] In one embodiment of the present invention, the electrical device proposed by the present invention includes the battery device proposed by the present invention and described in detail in the above embodiments.

[0144] It should be noted that the electrical appliances shown in the accompanying drawings and described in this specification are merely a few examples among many electrical appliances from which the principles of the present invention can be applied. It should be clearly understood that the principles of the present invention are by no means limited to any detail or component of the electrical appliances shown in the accompanying drawings or described in this specification.

[0145] In summary, the electrical equipment proposed in this invention, by employing the battery device proposed in this invention, can avoid the impact of electrochemical corrosion caused by the atmospheric environment on the battery device, and can also avoid locking deformation of the battery device during secondary assembly, as well as avoid safety accidents caused by local heat accumulation in the battery device.

[0146] The foregoing describes and / or illustrates in detail exemplary embodiments of the method for preparing aluminum-copper gradient conductive busbars, conductive busbars, battery devices, and electrical equipment based on additive manufacturing technology proposed in this invention. However, the embodiments of this invention are not limited to the specific embodiments described herein; rather, components and / or steps of each embodiment may be used independently and separately from other components and / or steps described herein. Each component and / or step of one embodiment may also be used in combination with other components and / or steps of other embodiments. In describing the elements / components / etc. described and / or illustrated herein, the terms "a," "an," and "the above" are used to indicate the presence of one or more elements / components / etc. The terms "comprising," "including," and "having" are used to indicate an open-ended inclusion and mean that additional elements / components / etc. may exist in addition to those listed.

[0147] Although the method for preparing aluminum-copper gradient conductive busbars, conductive busbars, battery devices, and electrical equipment based on additive manufacturing technology proposed in this invention has been described with respect to different specific embodiments, those skilled in the art will recognize that modifications can be made to the implementation of this invention within the spirit and scope of the claims.

Claims

1. A method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology, characterized in that, include: We provide copper plates, pure aluminum welding wire, and pure copper welding wire, with copper plates as the welding base, pure aluminum welding wire as the aluminum welding layer, and pure copper welding wire as the copper welding layer. The deposition path of the 3D model of the conductive bus is sliced ​​and parameters are set; According to the set parameters, a cold metal transition additive manufacturing system is used to perform arc additive welding on a copper plate to obtain a thin-walled structure for the power lead-out device of a battery module. The thin-walled structure includes an aluminum welding layer, a copper welding layer and a welding substrate stacked from top to bottom. The thin-walled structure is modified according to the requirements of the battery module to obtain the required conductive busbar; The step of providing the copper plate includes: removing stains from the surface of the copper plate; The cleaned copper plate is placed in a heating device for preheating treatment at a temperature of 520℃~650℃. In the aforementioned arc additive welding step, the interlayer cooling time for the copper side is 1 min to 1.5 min, the interlayer cooling time for the aluminum side is 1.5 min to 2 min, the interlayer cooling temperature is 80℃ to 120℃, and the cooling temperature of the last copper layer is 300℃ to 400℃.

2. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 1, characterized in that, The step of removing stains from the surface of the copper plate includes: The surface of the copper plate is mechanically polished. The copper plate was placed in an ultrasonic cleaner for cleaning with anhydrous ethanol.

3. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 2, characterized in that, In the anhydrous ethanol cleaning step, the cleaning time is 35 min to 60 min.

4. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 1, characterized in that, In the aforementioned preheating treatment step: The heating equipment is a vacuum box furnace; and / or The preheating time is 1.5h to 3h.

5. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 1, characterized in that: The copper plate is a T2-Y pure copper plate; and / or The dimensions of the copper plate are (100mm~300mm)×(100mm~300mm)×(5mm~10mm).

6. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 1, characterized in that, The step of providing pure aluminum welding wire includes surface treatment of the pure aluminum welding wire.

7. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 6, characterized in that, The surface treatment step for the pure aluminum welding wire includes: The pure aluminum welding wire was wiped with anhydrous ethanol and then dried at 55℃~75℃.

8. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 1, characterized in that, The step of providing pure copper welding wire includes surface treatment of the pure copper welding wire.

9. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 8, characterized in that, The surface treatment step for the pure copper welding wire includes: The pure copper welding wire was wiped with anhydrous ethanol and then dried at 55℃~75℃.

10. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 1, characterized in that: The pure aluminum welding wire is ER1070 welding wire; and / or The pure copper welding wire is S201 welding wire.

11. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 1, characterized in that, The height ratio of the aluminum weld layer, the copper weld layer, and the weld substrate is 16:16:

1.

12. The method for preparing aluminum-copper gradient conductive busbars based on additive manufacturing technology according to claim 1, characterized in that: In the aforementioned arc additive welding step, the process parameters for copper-side welding are as follows: welding current 125A~140A, welding voltage 10V~14V, welding speed 0.15m / min~0.35m / min, shielding gas 99.99% argon gas, shielding gas flow rate 15L / min, wire feed speed 4m / min~6m / min, and wire extension length 15mm~20mm; and / or In the aforementioned arc additive welding step, the process parameters for welding the aluminum side are as follows: welding current of 75A~90A, welding voltage of 8V~11V, welding speed of 0.15m / min~0.35m / min, shielding gas of 99.99% argon by volume, shielding gas flow rate of 15L / min, wire feed speed of 1m / min~1.5m / min, and wire extension length of 20mm~25mm.

13. A conductive busbar for electrically connecting two adjacent battery modules via a copper busbar, characterized in that, The conductive bus is prepared by the method for preparing aluminum-copper gradient conductive bus based on additive manufacturing technology as described in any one of claims 1 to 12.

14. A conductive busbar for electrically connecting two adjacent battery modules via a copper busbar, characterized in that, The conductive bus includes a lead-out portion, a connecting portion, and a lap portion. The connecting portion has an upper end and a lower end. The lead-out portion is connected to one of the upper and lower ends of the connecting portion and is used to connect to the terminal post of one of the battery modules. The lap portion is connected to the other of the upper and lower ends of the connecting portion and is used to connect the copper bus and connect to another battery module via the copper bus. The lead-out portion and the lap portion are bent towards opposite sides relative to the connecting portion. The lead-out portion is made of an aluminum-copper composite material or aluminum, the connecting portion is made of an aluminum-copper composite material or copper, and the lap portion is made of copper. The conductive bus is prepared using the aluminum-copper gradient fabrication process based on additive manufacturing technology as described in any one of claims 1 to 12.

15. A battery device, characterized in that, Includes the conductive bus as described in claim 13 or 14.

16. An electrical appliance, characterized in that, Includes the battery device as described in claim 15.

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