Aluminum composite current collector, method for manufacturing the same, positive electrode sheet, battery, and power consumption device

Abstract

The present invention relates to the technical field of batteries, and specifically to an aluminum composite current collector, a method for manufacturing the same, a positive electrode sheet, a battery, and a power consumption device. The method for manufacturing the aluminum composite current collector includes the steps of providing a polymer film, evaporating metallic aluminum under vacuum conditions using a vacuum ion evaporation process, turning on an ion source to inject argon ions, and bringing the argon ions into contact with the aluminum vapor to plate aluminum metal layers on both sides of the polymer film, wherein the argon ions are pulsed into the deposition chamber. The above method for manufacturing the aluminum composite current collector can improve the surface roughness and specific surface area.

Description

Technical Field

[0001] The present invention relates to the technical field of batteries, and more specifically, to an aluminum composite current collector, a method for manufacturing the same, a positive electrode sheet, a battery, and a power consumption device.

Background Art

[0002] Current metal composite current collectors mainly include a metal layer and a polymer layer located between the metal layers, and their manufacturing method is usually completed by vacuum depositing the metal layer on the polymer layer. Currently, both the polymer layer and the metal layer of the conventional composite current collector are dense and have a very smooth surface, with both the surface roughness and the specific surface area being small and the surface energy being low. Therefore, when applying the electrode slurry to the composite current collector, the following problems occur. 1. Due to the low surface energy of the metal layer, coating leakage of the electrode slurry is likely to occur, resulting in poor product quality and limited coating speed. 2. Since the specific surface area of the metal layer is small, the adhesion area between the electrode active material and the metal layer is small, the adhesion force between the electrode active material layer and the composite current collector is low, and powder falling is likely to occur. At the same time, since the adhesion area is small, the conductive path between the electrode active material and the composite current collector is small, and the interfacial resistance between the electrode active material and the metal layer of the composite current collector increases.

Summary of the Invention

Problems to be Solved by the Invention

[0003] Based on this, it is necessary to provide an aluminum composite current collector, a method for manufacturing the same, a positive electrode sheet, a battery, and a power consumption device that can improve the surface roughness and specific surface area.

Means for Solving the Problems

[0004] One aspect of the present invention is providing a polymer film, Using a vacuum ion evaporation process, evaporate metallic aluminum under vacuum conditions, turn on the ion source to inject argon ions, bring the argon ions into contact with the aluminum vapor, and plate aluminum metal layers on both sides of the polymer film. The method includes the step of pulse-injecting the argon ions into the evaporation chamber, and the number of pulses of the argon ions is 10 to 20 times. The ratio of the amount of argon ions in one pulse injection to the aluminum vapor content is 1:8000 to 3:1000, and the pulse interval between two pulse injections of the argon ions is 0.1 s to 10 s. A method for manufacturing an aluminum composite current collector is provided.

[0005] In some embodiments, the concentration of the aluminum vapor is maintained at 60 mol / L to 80 mol / L.

[0006] In some embodiments, the amount of argon ions in each pulse injection is 10 mol to 180 mol.

[0007] In some embodiments, the pulse time for each time is 5 s to 10 s.

[0008] In one embodiment, the evaporation temperature of the metallic aluminum is 600 °C to 1600 °C, the degree of vacuum is less than 1×10 -2 Pa, and / or the moving speed of the polymer film is 10 m / min to 100 m / min.

[0009] In one embodiment, the material of the polymer film is selected from the group consisting of a composite of an insulating polymer material and an inorganic non-conductive filler, a composite of an insulating polymer material and a conductive filler, an insulating polymer material, or a conductive polymer material. In the composite of the insulating polymer material and the inorganic non-conductive filler, the mass percentage of the insulating polymer material is 90% or more. In the composite of the insulating polymer material and the conductive filler, the mass percentage of the insulating polymer material is 90% or more.

[0010] In one embodiment, the insulating polymer material is one or more selected from the group consisting of cellulose and its derivatives, starch and its derivatives, protein and its derivatives, polyvinyl alcohol and its cross-linked polymers, polyethylene glycol and its cross-linked polymers, polyamide, polyterephthalate, polyimide, polyethylene, polypropylene, polystyrene, polyvinyl chloride, aramid, poly-m-phenylene isophthalamide, acrylonitrile-butadiene-styrene copolymer, polyethylene terephthalate, polybutylene terephthalate, polyparaphenylene terephthalamide, polypropylene ethylene, polyoxymethylene, epoxy resin, phenol resin, polytetrafluoroethylene, polyvinylidene fluoride, silicone rubber and polycarbonate, and / or the conductive polymer material is selected from the group consisting of doped polysulfur nitride and / or doped polyacetylene, and / or the inorganic non-conductive filler is one or more selected from the group consisting of ceramic materials, glass materials and ceramic composite materials, and / or the conductive filler is one or more selected from the group consisting of carbon black, carbon nanotube, graphite, acetylene black, graphene, nickel, iron, copper, aluminum, alloy, nickel-coated graphite powder and nickel-coated carbon fiber.

[0011] In one embodiment, after plating aluminum metal layers on both sides of the polymer film, it further includes a winding step, Optionally, the winding tension is 5N to 25N.

[0012] One aspect of the present invention further provides an aluminum composite current collector manufactured by the manufacturing method of the above aluminum composite current collector.

[0013] In one embodiment, the aluminum composite current collector is (1) having a performance with a surface roughness of 0.2 μm or more, (2) having a performance with a specific surface area of 25 m 2 / g or more. (3) Performance with a puncture strength of 200 gf or more, (4) Performance having at least one of the following: a longitudinal tensile strength of 150 MPa or more, a longitudinal elongation rate of 10% or more, a transverse tensile strength of 150 Mpa or more, and a transverse elongation rate of 10% or more.

[0014] Another aspect of the present invention further provides a positive electrode including the above aluminum composite current collector and a positive electrode active material layer located on at least one surface of the aluminum composite current collector.

[0015] Yet another aspect of the present invention provides a battery including the above positive electrode.

[0016] Still yet another aspect of the present invention further provides a power consumption device including the above battery.

[0017] In the method for manufacturing the above aluminum composite current collector, in the process of depositing metallic aluminum, argon ions are pulse-injected, and by adjusting the related parameters of the argon ions and the aluminum vapor, the aluminum vapor can be crystallized under the action of the argon ions to form particulate metallic aluminum and continue to deposit on the polymer film. Thereby, the surface roughness and specific surface area of the aluminum composite current collector can be increased. Compared with the manufacturing process of the conventional aluminum composite current collector, the roughness and specific surface area of the aluminum composite current collector manufactured by the above manufacturing method are improved by at least 50% at the lowest.

[0018] Furthermore, after assembling the above manufactured aluminum composite current collector into a positive electrode and a battery, the peeling force between the positive electrode active material layer and the aluminum composite current collector is significantly improved, the internal resistance of the battery is reduced, and the charge-discharge cycle performance of the battery is significantly improved.

[0019] To more clearly explain the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings necessary for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative labor.

Brief Description of the Drawings

[0020]

Figure 1

Modes for Carrying Out the Invention

[0021] A detailed description of the embodiments of the present invention is provided, and one or more examples thereof are described below. Each embodiment is described for the purpose of explaining the present invention and is not intended to limit the present invention. In fact, it will be apparent to those skilled in the art that various modifications and changes can be made to the present invention without departing from the scope or spirit of the present invention. For example, it is also possible to use the features described or illustrated as part of one embodiment in another embodiment to obtain further embodiments.

[0022] Therefore, the present invention is intended to cover such modifications and variations as fall within the scope of the appended claims and their equivalents. Other objects, features, and aspects of the present invention will be disclosed or become apparent from the following detailed description. It should be understood by those skilled in the art that this specification is only an explanation of exemplary embodiments and is not intended to limit the broader aspects of the present invention.

[0023] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terms used in the description of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items. The terms "comprise", "include", "have", "contain" or other variations thereof are intended to cover non-exclusive inclusion. For example, a composition, step, method, product or apparatus containing the listed elements is not necessarily limited to only those elements, and may include other elements not expressly listed or elements inherent to such composition, step, method, product or apparatus.

[0024] Except in the examples of operations or as otherwise indicated, all numbers used in this specification and the claims to represent amounts of components, physicochemical properties, etc. are to be understood in all cases as being modified by the term "about". Therefore, for example, unless there is a contrary description, the numerical parameters recited in the above specification and the appended claims are all approximate values, and those skilled in the art can appropriately change these approximate values by using the desired characteristics obtained by the teachings disclosed herein. The use of a numerical range indicated by endpoints includes all numbers within that range and any range contained within that range. For example, 1 to 5 includes 1, 1.1, 1.3, 1.5, 2, 2.75, 3, 3.80, 4, and 5, etc.

[0025] The first object of the present invention is providing a polymer film, and Using a vacuum ion evaporation process, evaporate metallic aluminum under vacuum conditions, turn on the ion source to inject argon ions, bring the argon ions into contact with the aluminum vapor, and plate aluminum metal layers on both sides of the polymer film. The method includes the step of pulse-injecting the argon ions into the evaporation chamber. Provided is a method for manufacturing an aluminum composite current collector. In some embodiments, the number of pulses of the argon ions is 10 to 20 times, the ratio of the amount of argon ions in one pulse injection to the aluminum vapor content is 1:8000 to 3:1000, and the pulse interval between two pulse injections of the argon ions is 0.1 s to 10 s.

[0026] In the above method for manufacturing an aluminum composite current collector, during the process of depositing metallic aluminum, argon ions are pulse-injected, and by adjusting the relevant parameters of the argon ions and the aluminum vapor, the aluminum vapor can be crystallized under the action of the argon ions to form particulate metallic aluminum and continue to deposit on the polymer film. Thereby, the surface roughness and specific surface area of the aluminum composite current collector are increased. Compared with the manufacturing process of the conventional aluminum composite current collector, the roughness and specific surface area of the aluminum composite current collector manufactured by the above manufacturing method are improved by at least 50% or more.

[0027] Furthermore, by introducing argon ions, first, the energy of argon ions is utilized to affect the crystal topography and grain boundary structure, improve crystal growth and crystallinity. Also, the impact action of argon ions can be used to increase the deposited atom energy, and the increased deposited atom energy is beneficial for the formation of a more stable crystal plane. Additionally, by injecting argon ions in a pulse form, the injection time and dosage of argon ions can be accurately controlled, and the deposition rate can be increased. By injecting argon ions in a pulse form and changing the pulse injection amount, pulse number, pulse time, and the interval time between two pulses, the frequency and intensity of argon ion collision on the surface can be adjusted, not only making the plating layer contain different crystal topographies, but also forming a multi-layer aluminum structure. Furthermore, the number of aluminum layers with different crystal forms and the thickness of aluminum layers with different crystal forms in the plating layer can be controlled, effectively improving the corrosion resistance, specific surface area, and surface roughness compared with the conventional vacuum aluminum plating film.

[0028] In some embodiments, the pulse interval time between two pulse injections of argon ions refers to the time when no argon ions are pulse-injected between two pulse injections.

[0029] In some embodiments, the pulse injection interval time of argon ions may be any value between 0.1 s and 10 s, and may also be 0.1 s, 1 s, 2 s, 3 s, 4 s, 5 s, 6 s, 7 s, 8 s, 9 s, or 10 s.

[0030] In some embodiments, the continuous pulse number refers to the continuous pulse number of argon ion pulse injection in one aluminum evaporation process.

[0031] In some embodiments, the pulse time for each time refers to the duration of injecting argon ions in each pulse injection process.

[0032] In some embodiments, the amount of argon ions injected per pulse is expressed in moles. In some embodiments, the aluminum vapor content in the evaporation chamber is equal to the product of the concentration of aluminum vapor and the volume of the evaporation chamber.

[0033] In some embodiments, the number of consecutive pulses may be any value between 10 and 20, and may be 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20. The pulse time for each pulse may be any value between 5 s and 10 s, and may be 6 s, 7 s, 8 s, or 9 s. The ratio of the amount of each pulse injection to the aluminum vapor content in the evaporation chamber may be any value between 1:8000 and 3:1000, and may be 1:8000, 1:7000, 1:6000, 1:5000, 1:4000, 1:3000, 1:2000, 1:1500, 1:1000, 1:500, or 3:1000.

[0034] In some embodiments, the temperature for evaporating metallic aluminum may be 600°C to 1600°C, and may be 800°C, 1000°C, 1200°C, or 1400°C. The degree of vacuum is less than 1×10 -2 Pa.

[0035] In some embodiments, the moving speed of the polymer film may be 10 m / min to 100 m / min, and may be 20 m / min, 50 m / min, 70 m / min, 80 m / min, or 90 m / min.

[0036] In some embodiments, the metallic aluminum is high-purity aluminum, that is, the aluminum purity is 99.8% or more.

[0037] In some embodiments, the particle size of the aluminum metal particles in the aluminum metal layer is 10 nm to 80 nm.

[0038] In some embodiments, the material of the polymer film is not limited, and a polymer commonly used in this field can be selected. For example, it can be selected from the group consisting of a composite of an insulating polymer material and an inorganic non-conductive filler, a composite of an insulating polymer material and a conductive filler, an insulating polymer material, or a conductive polymer material. In the composite of an insulating polymer material and an inorganic non-conductive filler, the mass percentage of the insulating polymer material is 90% or more. In the composite of an insulating polymer material and a conductive filler, the mass percentage of the insulating polymer material is 90% or more.

[0039] In some embodiments, the insulating polymer material may be one or more selected from the group consisting of cellulose and its derivatives, starch and its derivatives, protein and its derivatives, polyvinyl alcohol and its cross-linked polymers, polyethylene glycol and its cross-linked polymers, polyamide, polyterephthalate, polyimide, polyethylene, polypropylene, polystyrene, polyvinyl chloride, aramid, poly-m-phenylene isophthalamide, acrylonitrile-butadiene-styrene copolymer, polyethylene terephthalate, polybutylene terephthalate, polyparaphenylene terephthalamide, polypropylene ethylene, polyoxymethylene, epoxy resin, phenolic resin, polytetrafluoroethylene, polyvinylidene fluoride, silicone rubber, and polycarbonate.

[0040] In some embodiments, the conductive polymer material may be selected from the group consisting of doped polysulfur nitride and / or doped polyacetylene.

[0041] In some embodiments, the inorganic non-conductive filler may be one or more selected from the group consisting of ceramic materials, glass materials, and ceramic composite materials.

[0042] In some embodiments, the conductive filler may be one or more selected from the group consisting of carbon black, carbon nanotubes, graphite, acetylene black, graphene, nickel, iron, copper, aluminum, alloys, nickel-coated graphite powder, and nickel-coated carbon fibers. The alloy may include one or more of nickel, iron, copper, and aluminum.

[0043] In some embodiments, after plating aluminum metal layers on both sides of the polymer film, it further includes a winding step. Optionally, the winding tension may be 5 N to 25 N.

[0044] One aspect of the present invention further provides an aluminum composite current collector manufactured by the manufacturing method of the above aluminum composite current collector. After assembling the manufactured aluminum composite current collector into a positive electrode and a battery, the peeling force between the positive electrode active material layer and the aluminum composite current collector is significantly improved, reducing the internal resistance of the battery and significantly improving the charge-discharge cycle performance of the battery.

[0045] In some embodiments, the aluminum composite current collector has a surface roughness of 0.2 μm or more, a specific surface area of 25 m 2 / g or more, a puncture strength of 200 gf or more, a longitudinal tensile strength of 150 MPa or more, a longitudinal elongation rate of 10% or more, a transverse tensile strength of 150 Mpa or more, and a transverse elongation rate of 10% or more.

[0046] In some embodiments, the thickness of the aluminum composite current collector is 3.6 μm to 31 μm, the thickness of the polymer film is 3 μm to 25 μm, and the thickness of the aluminum metal layer is 0.3 μm to 3 μm.

[0047] Another aspect of the present invention further provides a positive electrode including the above aluminum composite current collector and a positive electrode active material layer located on at least one surface of the aluminum composite current collector.

[0048] In some embodiments, a positive electrode active material layer is provided on both sides of the aluminum composite current collector.

[0049] In some embodiments, the positive electrode active material in the positive electrode active material layer may be any positive electrode active material known in the art. For example, it may be lithium cobaltate, lithium iron phosphate, NCA, NCM, lithium manganate, lithium nickelate, NCMA, or a cobalt-free positive electrode.

[0050] Yet another aspect of the present invention provides a battery including the above positive electrode.

[0051] In some embodiments, the battery may further include a negative electrode and an electrolyte.

[0052] Similarly, the negative electrode may be any negative electrode commonly used in the art, such as graphite, lithium, or lithium titanate.

[0053] In some embodiments, the electrolyte may be a solid electrolyte, a semi-solid electrolyte, or a liquid electrolyte. The solid electrolyte and the semi-solid electrolyte may be an oxide electrolyte or a sulfide electrolyte. The solute in the liquid electrolyte may be lithium hexafluorophosphate.

[0054] In some embodiments, the above battery may further include a separator, and the separator may be any separator known in the art, such as a PE wet separator, a PP dry separator, or a two-layer PE / PP coated separator.

[0055] The shape of the battery is not limited. For example, it may be cylindrical, square, or an aluminum laminate film pouch.

[0056] In some embodiments, the battery may be a lithium-ion battery.

[0057] Yet another aspect of the present invention further provides a power consumption device including the above battery.

[0058] In some embodiments, specific types of power consumption devices include, but are not limited to, mobile terminals (such as mobile phones, notebook computers, etc.), smart wearables, power tools (such as electric drills, motors, etc.), electric vehicles, mobile batteries, and the like.

[0059] Hereinafter, the present invention will be described in more detail with reference to specific embodiments.

[0060] Example 1: Manufacture of an aluminum composite current collector An aluminum composite current collector was manufactured using a vacuum ion deposition process, and the polymer film was a polyethylene terephthalate (PET) film. The specific steps are as follows.

[0061] In step 1), after evacuating the deposition chamber of the vacuum ion deposition apparatus, a polyethylene terephthalate (PET) film with a thickness of 6 μm was placed into the deposition chamber as a deposition substrate. Then, high-purity aluminum with a purity of 99.9% was placed in the deposition boat and evaporated at 800 °C. During the deposition process, the aluminum vapor concentration was maintained at 70 mol / L, and the evaporation rate was set to 30 m / min.

[0062] In step 2), argon ion vapor was injected into a deposition chamber of 1000 L with a pulse interval time of 5 s by an ion source in a vacuum ion deposition apparatus. The pulse time of each argon ion was 8 s, the injection amount per time was 50 mol, and the number of pulses was 12 times. By adding argon ions, aluminum vapor was crystallized to form aluminum metal particles, which continued to deposit on the two upper and lower surfaces of the PET film to form an aluminum metal layer. The thickness of the aluminum metal layers on the upper and lower surfaces was 1 μm each. It was wound up with a tension of 5 N to manufacture an aluminum composite current collector with a thickness of 8 μm. The SEM diagram of the aluminum composite current collector is shown in Fig. 1. As can be seen from Fig. 1, the surface of the aluminum composite current collector was rough, and by calculation, the particle size of the aluminum metal particles in the aluminum metal layer was 80 nm. The related performance of the measured aluminum composite current collector is shown in Table 1.

[0063] Battery assembly: The positive electrode consists of the aluminum composite current collector manufactured above and a lithium iron phosphate active material layer coated on the aluminum composite current collector. The negative electrode is graphite. The electrolyte is a liquid electrolyte with lithium hexafluorophosphate as the solute. The separator is a polyethylene (PE) microporous separator. The above components were assembled into a lithium iron phosphate battery with a model number of 100 Ah, and related performance tests were carried out. The test results are shown in Table 2.

[0064] Example 2: Manufacture of aluminum composite current collector The manufacturing method of this example is substantially the same as that of Example 1 except that the polymer film is a polypropylene film, the thickness of the polypropylene film is 10 μm, and the thickness of the aluminum metal layer is 1.5 μm. The specific steps are as follows.

[0065] In step 1), after evacuating the deposition chamber of the vacuum ion deposition apparatus, a polypropylene film with a thickness of 10 μm was placed into the deposition chamber as a deposition substrate. Then, high-purity aluminum with a purity of 99.9% was placed in the deposition boat and evaporated at 800 °C. During the deposition process, the aluminum vapor concentration was maintained at 70 mol / L, and the evaporation rate was set at 30 m / min.

[0066] In step 2), argon ion vapor was injected into the 1000 L deposition chamber with a pulse interval time of 5 s by the ion source in the vacuum ion deposition apparatus. The pulse time of each argon ion pulse was 8 s, the injection amount per time was 50 mol, and the number of pulses was 12. By adding argon ions, the aluminum vapor was crystallized to form aluminum metal particles, which continued to deposit on the two upper and lower surfaces of the PET film to form an aluminum metal layer. The thickness of the aluminum metal layers on the upper and lower surfaces was 1.5 μm each, and it was wound up with a tension of 5 N to produce an aluminum composite current collector with a thickness of 13 μm.

[0067] Example 3: Production of Aluminum Composite Current Collector The manufacturing method of this example is almost the same as that of Example 1, except that the polymer film is a graphite-modified polyethylene film, the thickness of the graphite-modified polyethylene film is 18 μm, and the thickness of the aluminum metal layer is 3 μm. The specific steps are as follows.

[0068] In step 1), after evacuating the deposition chamber of the vacuum ion deposition apparatus, a graphite-modified polyethylene film (the mass percentage of polyethylene is 95%) with a thickness of 18 μm was placed into the deposition chamber as a deposition substrate. Then, high-purity aluminum with a purity of 99.9% was placed in the deposition boat and evaporated at 800 °C. During the deposition process, the aluminum vapor concentration was maintained at 70 mol / L, and the evaporation rate was set at 30 m / min.

[0069] Step 2) Using the ion source in the vacuum ion evaporation apparatus, argon ion vapor was injected into the 1000 L evaporation chamber with a pulse interval time of 5 s. The pulse time of argon ions each time was 8 s, the injection amount per time was 50 mol, and the number of pulses was 12 times. By adding argon ions, aluminum vapor was crystallized to form aluminum metal particles, which continued to deposit on the two upper and lower surfaces of the PET film to form an aluminum metal layer. The thickness of the aluminum metal layers on the upper and lower surfaces was 3 μm each. It was wound up with a tension of 5 N to produce an aluminum composite current collector with a thickness of 24 μm.

[0070] Example 4: Manufacture of Aluminum Composite Current Collector The manufacturing method of this example is almost the same as that of Example 1 except that the vacuum evaporation parameters are different. Specifically, it is as follows.

[0071] In Step 1), after evacuating the evaporation chamber of the vacuum ion evaporation apparatus, a polyethylene terephthalate (PET) film with a thickness of 6 μm was placed into the evaporation chamber as the evaporation substrate. Then, high-purity aluminum with a purity of 99.9% was placed in the evaporation boat and evaporated at 1000 °C. During the evaporation process, the aluminum vapor concentration was maintained at 60 mol / L, and the evaporation rate was 50 m / min.

[0072] In Step 2), using the ion source in the vacuum ion evaporation apparatus, argon ion vapor was injected into the 1000 L evaporation chamber with a pulse interval time of 5 s. The pulse time of argon ions each time was 5 s, the injection amount per time was 30 mol, and the number of pulses was 12 times. By adding argon ions, aluminum vapor was crystallized to form aluminum metal particles, which continued to deposit on the two upper and lower surfaces of the PET film to form an aluminum metal layer. The thickness of the aluminum metal layers on the upper and lower surfaces was 1 μm each. It was wound up with a tension of 5 N to produce an aluminum composite current collector with a thickness of 8 μm.

[0073] Example 5: Manufacture of Aluminum Composite Current Collector The manufacturing method of this example is almost the same as that of Example 1 except for different vacuum evaporation parameters. Specifically, it is as follows.

[0074] In step 1), after evacuating the evaporation chamber of the vacuum ion evaporation device, a polyethylene terephthalate (PET) film with a thickness of 6 μm was placed into the evaporation chamber as the evaporation substrate. Then, high-purity aluminum with a purity of 99.9% was placed in the evaporation boat and evaporated at 1400 °C. During the evaporation process, the aluminum vapor concentration was maintained at 80 mol / L, and the evaporation rate was 80 m / min.

[0075] In step 2), using the ion source in the vacuum ion evaporation device, argon ion vapor was injected into the 1000 L evaporation chamber with a pulse interval time of 5 s. The pulse time of each argon ion was 10 s, the injection amount per time was 50 mol, and the number of pulses was 12 times. By adding argon ions, the aluminum vapor was crystallized to form aluminum metal particles, which continued to deposit on the two upper and lower surfaces of the PET film to form an aluminum metal layer. The thickness of the aluminum metal layers on the upper and lower surfaces was 1 μm each. It was wound up with a tension of 5 N to manufacture an aluminum composite current collector with a thickness of 8 μm.

[0076] Comparative Example 1: Manufacturing of Aluminum Composite Current Collector Different from the manufacturing process of Example 1, the specific steps are as follows.

[0077] Aluminum with a purity of 99.9% was selected as the plating material, and using vacuum evaporation, aluminum metal layers with a thickness of 1 μm were respectively deposited on the upper and lower surfaces of a 6-μm-thick PET film, wound up, unwound, and an aluminum composite current collector was manufactured. The process parameters of the vacuum evaporation were that the aluminum vapor concentration was 150 mol / L, the evaporation temperature was 800 °C, the evaporation rate was 50 m / min, the winding tension was 5 N, and the unwinding tension was 20 N. The related performance of the measured aluminum composite current collector is shown in Table 1.

[0078] Battery assembly: The positive electrode consists of the aluminum composite current collector manufactured above and a lithium iron phosphate active material layer coated on the aluminum composite current collector. The negative electrode is graphite. The electrolyte is a liquid electrolyte with lithium hexafluorophosphate as the solute. The separator is a polyethylene (PE) microporous separator. Assemble the above components into a lithium iron phosphate battery with a model number of 100 Ah, conduct relevant performance tests, and show the test results in Table 2.

[0079] Comparative Example 2: Manufacture of Aluminum Composite Current Collector The manufacturing method of this comparative example is almost the same as that of Example 1 except that the aluminum vapor concentration is 180 mol / L. The specific steps are as follows.

[0080] In step 1), after evacuating the deposition chamber of the vacuum ion deposition apparatus, a polyethylene terephthalate (PET) film with a thickness of 6 μm was placed into the deposition chamber as a deposition substrate. Then, high-purity aluminum with a purity of 99.9% was placed in the deposition boat and evaporated at 800 °C. During the deposition process, the aluminum vapor concentration was maintained at 180 mol / L, and the evaporation rate was 30 m / min.

[0081] In step 2), argon ion vapor was injected into the deposition chamber of 4000 L with a pulse interval time of 5 s by the ion source in the vacuum ion deposition apparatus. The pulse time of each argon ion was 8 s, the injection amount per time was 50 mol, and the number of pulses was 12 times. By adding argon ions, the aluminum vapor was crystallized to form aluminum metal particles, which continued to deposit on the two upper and lower surfaces of the PET film to form an aluminum metal layer. The thickness of the aluminum metal layers on the upper and lower surfaces was 1 μm each, and it was wound up with a tension of 5 N to manufacture an aluminum composite current collector with a thickness of 8 μm. The relevant performance of the measured aluminum composite current collector is shown in Table 1.

[0082] Battery Assembly: The positive electrode consists of the above-mentioned manufactured aluminum composite current collector and a lithium iron phosphate active material layer coated on the aluminum composite current collector. The negative electrode is graphite. The electrolyte is a liquid electrolyte with lithium hexafluorophosphate as the solute. The separator is a polyethylene (PE) microporous separator. The above-mentioned components are assembled into a lithium iron phosphate battery with a model number of 100 Ah, and relevant performance tests are carried out. The test results are shown in Table 2.

[0083] Comparative Example 3: Manufacture of Aluminum Composite Current Collector The manufacturing method of this comparative example is almost the same as that of Example 1 except that the single injection amount of argon ion implantation is 200 mol. The specific steps are as follows.

[0084] In Step 1), after evacuating the deposition chamber of the vacuum ion deposition apparatus, a polyethylene terephthalate (PET) film with a thickness of 6 μm was placed into the deposition chamber as the deposition substrate. Then, high-purity aluminum with a purity of 99.9% was placed in the deposition boat and evaporated at 800 °C. During the deposition process, the aluminum vapor concentration was maintained at 70 mol / L, and the evaporation rate was 30 m / min.

[0085] In Step 2), argon ion vapor was injected into the 500 L deposition chamber with a pulse interval time of 5 s by the ion source in the vacuum ion deposition apparatus. The pulse time of each argon ion was 8 s, the single injection amount was 200 mol, and the number of pulses was 12. By adding argon ions, the aluminum vapor was crystallized to form aluminum metal particles, which continued to deposit on the two upper and lower surfaces of the PET film to form an aluminum metal layer. The thickness of the aluminum metal layers on the upper and lower surfaces was 1 μm each, and it was wound up with a tension of 5 N to manufacture an aluminum composite current collector with a thickness of 8 μm. The relevant performance of the measured aluminum composite current collector is shown in Table 1.

[0086] Battery Assembly: The positive electrode consists of the manufactured aluminum composite current collector and a lithium iron phosphate active material layer coated on the aluminum composite current collector. The negative electrode is graphite. The electrolyte is a liquid electrolyte with lithium hexafluorophosphate as the solute. The separator is a polyethylene (PE) microporous separator. The above components are assembled into a lithium iron phosphate battery with a model number of 100 Ah, and relevant performance tests are conducted. The test results are shown in Table 2.

[0087] Table 1 Results of relevant performance tests of aluminum composite current collector

Table 1

[0088] The peel strength test, internal resistance test of the battery, and charge-discharge cycle performance test refer to Chinese National Standard GB18287_2000, and the test results are shown in Table 2.

[0089] 1) In the peel strength test, the peel strength between the aluminum composite current collector and the positive electrode active material layer in 10 PCS of lithium iron phosphate batteries assembled in Example 1 and Comparative Examples 1 - 3 was measured respectively, and the average value was taken.

[0090] 2) In the internal resistance test of the battery, the internal resistance of 10 PCS of lithium iron phosphate batteries assembled in Example 1 and Comparative Examples 1 - 3 was measured respectively, and the average value was taken.

[0091] 3) In the charge-discharge cycle performance test, when the capacity retention rate was 80%, at a 1C rate charge and 1C rate discharge (1C / 1C), the cycle performance of 10 PCS of lithium iron phosphate batteries assembled in Example 1 and Comparative Examples 1 - 3 was measured respectively, and the average value was taken.

[0092] Table 2 Results of performance tests of 100 Ah lithium iron phosphate battery

Table 2

[0093] Each technical feature of the above embodiments can be arbitrarily combined. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described, but these combinations of technical features should be regarded as within the scope of this specification as long as there is no contradiction.

[0094] The above embodiments only illustrate some embodiments of the present invention, and the description is specific and detailed, but it should not be understood as limiting the patent scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements to the present invention without departing from the gist of the present invention, and these also belong to the scope of the present invention. Therefore, the scope of patent protection of the present invention depends on the appended claims.

Claims

1. providing a polymer film; using a vacuum ion evaporation process to evaporate metallic aluminum under vacuum conditions, turning on an ion source to inject argon ions, bringing the argon ions into contact with the aluminum vapor, and plating aluminum metal layers on both sides of the polymer film, wherein the argon ions are pulse-injected into the evaporation chamber; A method for manufacturing an aluminum composite current collector, comprising the above steps.

2. The number of pulses of the argon ions is 10 to 20 times, the ratio of the amount of argon ions in a single pulse injection to the aluminum vapor content is 1:8000 to 3:1000, and the pulse interval between two pulse injections of the argon ions is 0.1 s to 10 s. The method for manufacturing an aluminum composite current collector according to Claim 1, characterized by the above.

3. The method is characterized in that it satisfies one or more of the following conditions: the evaporation temperature of metallic aluminum is 600°C to 1600°C, the degree of vacuum is less than 1×10 -2 Pa, and the moving speed of the polymer film is 10 m / min to 100 m / min. The method for manufacturing an aluminum composite current collector according to claim 1 or 2.

4. The material of the polymer film is selected from the group consisting of a composite of an insulating polymer material and an inorganic non-conductive filler, a composite of an insulating polymer material and a conductive filler, and an insulating polymer material and a conductive polymer material. The mass percentage of the insulating polymer material in the composite of the insulating polymer material and the inorganic non-conductive filler is 90% or more, and the mass percentage of the insulating polymer material in the composite of the insulating polymer material and the conductive filler is 90% or more. The method for manufacturing an aluminum composite current collector according to any one of Claims 1 to 3, characterized by the above.

5. The insulating polymer material is one or more selected from the group consisting of cellulose and its derivatives, starch and its derivatives, proteins and their derivatives, polyvinyl alcohol and its cross-linked polymers, polyethylene glycol and its cross-linked polymers, polyamides, polyesters, polyimides, polyethylenes, polypropylenes, polystyrenes, polyvinyl chlorides, aramids, poly-m-phenylene isophthalamide, acrylonitrile-butadiene-styrene copolymers, polyethylene terephthalate, polybutylene terephthalate, poly-p-phenylene terephthalamide, polypropylene ethylene, polyoxymethylene, epoxy resins, phenolic resins, polytetrafluoroethylene, polyvinylidene fluoride, silicone rubbers, and polycarbonates, and / or The conductive polymer material is selected from the group consisting of doped polysulfur nitride and / or doped polyacetylene, and / or the inorganic non-conductive filler is one or more selected from the group consisting of ceramic materials, glass materials, and ceramic composite materials, and / or the conductive filler is one or more selected from the group consisting of carbon black, carbon nanotubes, graphite, acetylene black, graphene, nickel, iron, copper, aluminum, alloys, nickel-coated graphite powder, and nickel-coated carbon fibers. The method for manufacturing an aluminum composite current collector according to claim 4, characterized in that.

6. After plating aluminum metal layers on both sides of the polymer film, it further includes a winding step, Optionally, the winding tension is 5 N to 25 N. The method for manufacturing an aluminum composite current collector according to any one of claims 1 to 5, characterized in that.

7. An aluminum composite current collector manufactured by the method for manufacturing an aluminum composite current collector according to any one of claims 1 to 6, characterized in that.

8. The aluminum composite current collector is (1) The surface roughness is 0.2 μm or more, (2) having a specific surface area of 25 m 2 / g or more, (3) The puncture strength is 200 gf or more, (4) The longitudinal tensile strength is 150 MPa or more, the longitudinal elongation rate is 10% or more, the transverse tensile strength is 150 Mpa or more, and the transverse elongation rate is 10% or more. The aluminum composite current collector according to claim 7, characterized in that it satisfies at least one of the above.

9. An anode comprising the aluminum composite current collector according to any one of claims 7 to 8 and a positive electrode active material layer located on at least one surface of the aluminum composite current collector, characterized in that.

10. A battery comprising the anode according to claim 9, characterized in that.

11. An electric power consumption device comprising the battery according to claim 10, characterized in that.

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