All-metal tab composite aluminum foil
By introducing an underlayer between the substrate and the aluminum plating layer, and utilizing polar groups to form hydrogen bonds or van der Waals forces, the problem of insufficient adhesion between the aluminum layer and the substrate is solved, extending battery life and improving manufacturing efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-28
- Publication Date
- 2026-03-03
AI Technical Summary
In existing technologies, the adhesion between the aluminum layer and the substrate is insufficient, which affects the stability of the composite aluminum foil and the service life of the battery.
An underlayer is introduced between the substrate and the first and second aluminum plating layers. The underlayer forms hydrogen bonds or van der Waals forces with the polar groups on the surface of the substrate, increasing the adhesion between the aluminum layer and the substrate. Furthermore, the welding of the substrate to the pure aluminum foil tabs reduces the need for individual tab welding.
It improves the adhesion between the aluminum layer and the substrate, extends battery life, and reduces subsequent manufacturing costs for the client while increasing manufacturing efficiency.
Smart Images
Figure CN223967347U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of lithium battery material technology, and in particular to an all-metal tab composite aluminum foil. Background Technology
[0002] With the continuous advancement and widespread application of lithium battery technology, market demands for battery performance are constantly increasing, particularly in terms of improved energy density, reduced weight, enhanced safety, and lower costs. As a key material for the positive electrode current collector in lithium batteries, composite aluminum foil plays a crucial role, offering significant advantages such as reduced battery weight, increased energy density, enhanced battery safety, and lower costs.
[0003] Currently, traditional composite aluminum foil typically uses multiple or two-stage vapor deposition methods to directly form an aluminum layer on the substrate surface. However, because the aluminum layer is directly deposited onto the substrate, the adhesion between the aluminum layer and the substrate is prone to become insufficient over time, thus affecting the stability of the composite aluminum foil and the battery's lifespan. Utility Model Content
[0004] The purpose of this invention is to address the problem in the prior art that the adhesion between the aluminum layer and the substrate is easily insufficient over time, thus affecting the stability of the composite aluminum foil and the service life of the battery. This invention provides an all-metal tab composite aluminum foil that increases the adhesion between the aluminum layer and the substrate and extends the battery life by introducing an underlayer between the substrate and the first and second aluminum plating layers.
[0005] To achieve the above objectives, this utility model provides an all-metal tab composite aluminum foil, comprising: a substrate, tabs, a base layer, a first aluminum plating layer, and a second aluminum plating layer, wherein one side of the tabs is welded to the substrate; the base layer is disposed on the surface of the substrate; the first aluminum plating layer is disposed on the upper surface of the substrate and is adhered to the base layer; and the second aluminum plating layer is disposed on the lower surface of the substrate and is adhered to the base layer.
[0006] As a further description of the above technical solution: the underlayment includes a first underlayment and a second underlayment, one side of the first underlayment is bonded to the upper surface of the substrate, the other side of the first underlayment is bonded to the first aluminum plating layer, one side of the second underlayment is bonded to the lower surface of the substrate, and the other side of the second underlayment is bonded to the second aluminum plating layer.
[0007] As a further description of the above technical solution: the substrate is made of PET, PP, PI or PPS material.
[0008] As a further description of the above technical solution: the electrode tab is made of pure aluminum foil.
[0009] As a further description of the above technical solution: the base layer is made of aluminum oxide.
[0010] As a further description of the above technical solution: the thickness of both the substrate and the tab is 5.0 μm.
[0011] As a further description of the above technical solution: the thickness of both the first aluminum plating layer and the second aluminum plating layer is 1.0 μm.
[0012] As a further description of the above technical solution: the thickness of both the first and second substrate layers is 20nm.
[0013] As a further description of the above technical solution: the coating method of the first aluminum plating layer and the second aluminum plating layer is induction heating aluminum plating.
[0014] As a further description of the above technical solution: the substrate is connected to the electrode by welding.
[0015] The above technical solution has the following advantages or beneficial effects:
[0016] This invention introduces an underlayer between the substrate and the first and second aluminum plating layers. The underlayer forms hydrogen bonds or van der Waals forces with the polar groups on the substrate surface, increasing the adhesion between the aluminum layer and the substrate and extending battery life. At the same time, by welding the substrate to the pure aluminum foil tabs before plating the underlayer and aluminum layers, the separate tab welding step is reduced, eliminating the need for the client to weld the tabs separately and improving the client's subsequent manufacturing efficiency. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the composite aluminum foil structure in one embodiment of the present invention;
[0018] Figure 2 This is a schematic diagram of the cutting of composite aluminum foil in one embodiment of the present invention. Figure 1 ;
[0019] Figure 3 This is a schematic diagram of the cutting of composite aluminum foil in one embodiment of the present invention. Figure 2 ;
[0020] Figure 4 This is a schematic diagram of the induction heating aluminum plating structure of composite aluminum foil in one embodiment of this utility model.
[0021] Legend:
[0022] 1. Substrate; 2. Electrode; 3. Undercoat; 4. First aluminum plating layer; 5. Second aluminum plating layer; 31. First undercoat; 32. Second undercoat. Detailed Implementation
[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0024] In the description of this utility model, it should be noted that the terms "vertical", "up", "down", "horizontal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0025] In the description of this utility model, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0026] like Figure 1-4 As shown, the present invention discloses an all-metal tab composite aluminum foil, comprising a substrate 1, tabs 2, a base layer 3, a first aluminum plating layer 4, and a second aluminum plating layer 5. One side of the tabs 2 is welded to the substrate 1; the base layer 3 is disposed on the surface of the substrate 1; the first aluminum plating layer 4 is disposed on the upper surface of the substrate 1 and is attached to the base layer 3; the second aluminum plating layer 5 is disposed on the lower surface of the substrate 1 and is attached to the base layer 3.
[0027] In the technical solution of this utility model, a base layer 3 is introduced between the substrate 1 and the first aluminum plating layer 4 and the second aluminum plating layer 5. The base layer 3 forms hydrogen bonds or van der Waals forces with the polar groups on the surface of the substrate 1, which increases the adhesion between the aluminum layer and the substrate 1 and extends the battery life. At the same time, by welding the substrate 1 to the pure aluminum foil tab 2 before plating the base layer 3 and the aluminum layer, the separate tab welding step is reduced. Compared with the traditional composite aluminum foil, the process of separately welding the tabs by the customer is eliminated, saving the customer's subsequent production costs and improving the customer's subsequent production efficiency.
[0028] Specifically, by first depositing a base layer 3 on the surface of substrate 1, and then depositing aluminum on the base layer 3, the adhesion between the aluminum layer and the substrate can be greatly improved, and the service life of the lithium battery can be improved simultaneously. This aluminum plating process is induction heating aluminum plating, which uses the principle of electromagnetic induction to generate eddy currents in conductive materials through an alternating magnetic field, so that the materials are rapidly heated to the evaporation temperature, thereby realizing the evaporation and coating of aluminum. The alternating magnetic field generates eddy currents in the aluminum material, resulting in resistance heating. The aluminum material is heated to the evaporation temperature (about 2467°C), and aluminum atoms escape from the surface. The escaped aluminum atoms condense on the surface of the substrate to form a uniform coating.
[0029] like Figure 1 and Figure 2 As shown, specifically, the underlayer 3 includes a first underlayer 31 and a second underlayer 32. One side of the first underlayer 31 is bonded to the upper surface of the substrate 1, and the other side of the first underlayer 31 is bonded to the first aluminum plating layer 4. One side of the second underlayer 32 is bonded to the lower surface of the substrate 1, and the other side of the second underlayer 32 is bonded to the second aluminum plating layer 5.
[0030] like Figure 1 and Figure 2 As shown, specifically, the substrate 1 is made of PET, PP, PI or PPS material, and the thickness of both the substrate 1 and the tab 2 is 5.0μm; the substrate 1 is 5.0μm thick and is made of polymer materials such as PET / PP / PI / PPS, which have high mechanical strength, high temperature resistance and electrolyte stability.
[0031] like Figure 1 and Figure 2 As shown, specifically, the substrate 3 is made of aluminum oxide, and the thickness of the first substrate 31 and the second substrate 32 is 20nm. The single layer thickness of the first substrate 31 and the second substrate 32 is 20nm. A dense oxide film is formed by magnetron sputtering to enhance the interfacial bonding force.
[0032] In this process, alumina forms hydrogen bonds or van der Waals forces with polar groups on the substrate surface (such as ester groups in PET), which improves adhesion. The dense alumina layer isolates the electrolyte from eroding the substrate, extending battery life. At the same time, the bottom layer 3 inhibits dendrite penetration and reduces the risk of short circuits.
[0033] like Figure 1 and Figure 2 As shown, specifically, the tab 2 is made of pure aluminum foil, and the thickness of the first aluminum plating layer 4 and the second aluminum plating layer 5 is 1.0 μm; the pure aluminum foil, with a thickness of 5.0 μm, is welded to the edge of the substrate to form a conductive path, avoiding the risk of short circuit in the aluminum-plastic film; the double-sided induction vapor-deposited aluminum layer, with a single layer thickness of 1.0 μm, provides high conductivity, with a total thickness of 7.0 μm, and the weight is reduced by 35.19% compared to pure aluminum foil.
[0034] The first aluminum plating layer 4 and the second aluminum plating layer 5 are plated by induction heating aluminum plating, and the substrate 1 and the electrode tab 2 are connected by welding.
[0035] Performance improvement comparison:
[0036] structure Adhesion Electrolyte resistant Aluminum + PET + Aluminum ≥4N / 15mm Soak at 70℃ for 1 day Aluminum + base layer + PET + base layer + aluminum ≥12N / 15mm 70℃ Immersion 3D
[0037] Specifically, such as Figure 3 and Figure 4 As shown, the specifications for manufacturing all-metal tab composite aluminum foil rolls are: tab 16mm * composite aluminum foil 190mm.
[0038] First, prepare a roll of substrate material such as PET / PP / PI / PPS with a width of 1350mm and a thickness of 5μm. Feed the material to the roll-to-roll rewinding machine, cut off the width of the welded pure aluminum foil tabs, and cut 3 strips with a width of 32mm. The running speed is 150±30m / min, the unwinding tension is 100N±10N, and the winding tension can be adjusted adaptively by the equipment.
[0039] Then, the cut substrate is rolled and welded according to the dimensions on a roll-to-roll rewinding machine. The running speed is 120±20m / min, the unwinding tension is 140N±10N, and the winding tension can be adjusted adaptively by the equipment. The welding width is 2±1mm, the welding pressure is 0.34±0.1Mpa, and the amplitude is 24±5%.
[0040] The material is then fed into a roll-to-roll magnetron coating machine to coat the A / B sides with an undercoat of aluminum oxide, approximately 20nm thick. Aluminum oxide enhances the adhesion between the aluminum layer and the substrate. Six aluminum targets, 99.95% pure, are used on each of the A / B sides. Oxygen is supplied during the aluminum coating process to form aluminum oxide. The coating parameters are as follows: winding speed 350±50m / min, power per target 7±0.5kw, total power per side approximately 42kw, oxygen supply 2500±200, unwinding tension 200±20N, and rewinding tension 180N±20N.
[0041] Then, the material with the A / B sides pre-coated is fed into a roll-to-roll induction heating aluminizing machine for A-side aluminizing. The specific coating method is induction heating aluminizing. The equipment is equipped with two cold rollers, each corresponding to 21 graphite crucibles with a diameter of 120mm and an induction heating kit to generate heat, for a total of 42 graphite crucibles. The 21 graphite crucibles are arranged in two rows, with 11 crucibles in the first row and 10 crucibles in the second row, which can achieve uniform coating while having sufficient evaporation. The process parameters are as follows: winding speed 14±2m / min, heating power of a single set of graphite crucibles 15±2kw, unwinding tension 140±10N, winding tension 120±10N, coating times 2 times, and new aluminum blocks need to be added to the graphite crucibles after each coating. The coating thickness is about 500nm per coating, and the total coating thickness of the two coatings is 1000±50nm.
[0042] After coating side A, the machine needs to be cleaned to remove excess waste aluminum slag from the evaporation area. Alternatively, a cleaned protective plate can be directly replaced. After cleaning, begin evaporating side B. The process parameters are as follows: winding speed 14±2m / min, heating power of a single graphite crucible 15±2kw, unwinding tension 150±10N, winding tension 130±10N, coating times 2. After each coating, a new aluminum block needs to be added to the graphite crucible. Each coating thickness is approximately 500nm, and the total coating thickness for both coatings is 1000±50nm.
[0043] Finally, the material is fed into the precision slitting machine for slitting and winding as shown in the diagram. There are seven circular slitting blades, each spaced 208mm apart. The slitting speed is 50m / min, the machine speed is 80m / min, the unwinding tension is 120N±20N, and the winding tension can be adjusted adaptively by the machine.
[0044] Six rolls of all-metal tab composite aluminum foil with a width of 16mm*190mm and a total thickness of 7μm can be obtained.
[0045] By employing seven slitting circular blades, each spaced 208mm apart, highly efficient slitting operations are achieved, ensuring cutting precision and efficiency even at high speeds. This configuration effectively improves production efficiency and reduces production cycles. Each slitting process, with seven blades cutting, yields six independent rolls of composite aluminum foil. This not only increases production output but also significantly improves production efficiency, while maintaining consistent size and quality for each roll.
[0046] Working principle: By introducing a base layer 3 between the substrate 1 and the first aluminum plating layer 4 and the second aluminum plating layer 5, hydrogen bonds or van der Waals forces are formed between the base layer 3 and the polar groups on the surface of the substrate 1, increasing the adhesion between the aluminum layer and the substrate 1 and extending the battery life. At the same time, by welding the substrate 1 to the pure aluminum foil tab 2 before plating the base layer 3 and the aluminum layer, the separate tab welding step is reduced. Compared with traditional composite aluminum foil, the process of separately welding the tabs by the customer is eliminated, saving the customer's subsequent production costs and improving the customer's subsequent production efficiency.
[0047] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.
[0048] The preferred embodiments of this utility model disclosed above are merely illustrative of the present utility model. These preferred embodiments do not exhaustively describe all details, nor do they limit the utility model to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of this utility model, thereby enabling those skilled in the art to better understand and utilize it. This utility model is limited only by the claims and their full scope and equivalents.
Claims
1. A composite aluminum foil with all-metal tabs, characterized in that, include: Substrate (1); A tab (2) is welded to the substrate (1) on one side; A base layer (3) is applied to the surface of the substrate (1); The first aluminum plating layer (4) is disposed on the upper surface of the substrate (1) and is adhered to the underlayment (3); The second aluminum plating layer (5) is disposed on the lower surface of the substrate (1) and is adhered to the underlayer (3).
2. The all-metal tab composite aluminum foil according to claim 1, characterized in that: The underlayment (3) includes a first underlayment (31) and a second underlayment (32). One side of the first underlayment (31) is attached to the upper surface of the substrate (1), and the other side of the first underlayment (31) is attached to the first aluminum plating layer (4). One side of the second underlayment (32) is attached to the lower surface of the substrate (1), and the other side of the second underlayment (32) is attached to the second aluminum plating layer (5).
3. The all-metal tab composite aluminum foil according to claim 1, characterized in that: The substrate (1) is made of PET, PP, PI or PPS material.
4. The all-metal tab composite aluminum foil according to claim 1, characterized in that: The tab (2) is made of pure aluminum foil.
5. The all-metal tab composite aluminum foil according to claim 1, characterized in that: The base layer (3) is made of aluminum oxide.
6. The all-metal tab composite aluminum foil according to claim 1, characterized in that: The thickness of both the substrate (1) and the tab (2) is 5.0 μm.
7. The all-metal tab composite aluminum foil according to claim 1, characterized in that: The thickness of the first aluminum plating layer (4) and the second aluminum plating layer (5) is 1.0 μm.
8. The all-metal tab composite aluminum foil according to claim 2, characterized in that: The thickness of the first substrate (31) and the second substrate (32) is 20nm.
9. The all-metal tab composite aluminum foil according to claim 1, characterized in that: The first aluminum plating layer (4) and the second aluminum plating layer (5) are coated by induction heating aluminum plating.
10. The all-metal tab composite aluminum foil according to claim 7, characterized in that: The substrate (1) and the tab (2) are connected by welding.