Functional current collector with high elongation and tensile strength as well as preparation method and application of functional current collector

Abstract

The invention discloses a functional current collector with high elongation and tensile strength and a preparation method and application thereof, and relates to the technical field of functional current collectors. According to the invention, polyvinyl chloride, zinc stannate, a calcium-zinc stabilizer and a plasticizer are mixed, and melt extrusion is carried out to obtain a modified polyvinyl chloride film; then magnetron sputtering and water electroplating are carried out, a metal layer is formed on the surface of the film in sequence, and drying is carried out to obtain the functional current collector. Wherein the zinc stannate 2 has two particle sizes; the plasticizer is one or a combination of more of dioctyl phthalate, dibutyl phthalate and poly (1, 2-propylene glycol adipate), and also comprises a cardanol plasticizer; the functional current collector obtained by the preparation method has good tensile strength and high elongation.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of functional current collector, in particular to high-elongation and tensile-strength functional current collector and its preparation method and application. BACKGROUND

[0002] With the rapid development of new energy and electronic technology, the cycle life, safety performance and energy density of the battery have become the top priority. As a very important part of the battery, the current collector is used to collect the current generated by the battery active material to form a larger current for external output, and its performance will directly affect the cycle life, energy density and safety of the battery. Currently, copper foil and aluminum foil are commonly used as the current collector in the positive and negative electrode sheets of lithium batteries and sodium batteries. Such current collectors have high cost and weight, which is not conducive to the control of battery cost and the improvement of energy density. In this regard, composite foil has obvious advantages compared to traditional foil. The composite foil current collector is usually a "sandwich" structure, with a polymer macromolecular layer in the inner layer and metal conductive layers on both sides. The current collector produced in the current industry usually uses 1-6 mu m of polyethylene terephthalate or polypropylene as the substrate, then magnetron sputtering is used to deposit a 30-60 nm copper layer on both sides of the substrate, and then water plating is used to obtain a 1 mu m or so copper layer. The composite foil current collector has a thin metal layer on the surface and a light polymer layer inside, which can effectively reduce the weight of the current collector as a whole, thereby increasing the energy density of the lithium ion battery. At the same time, the thin metal layer on the surface of the composite foil current collector is more likely to break than the traditional foil current collector when the lithium ion battery experiences thermal runaway, thereby isolating the active material from the current collector and preventing the lithium ion battery from continuing to experience thermal runaway.

[0003] Although the composite foil has the advantages of low cost and light weight, the tensile strength and ductility of the PP material are poor due to its own material properties, which affects the energy density, cycle life and safety of the battery. Currently, there is no ideal solution for making a high-ductility and adhesion functional current collector. SUMMARY

[0004] The present application aims to provide a high-elongation and tensile-strength functional current collector and its preparation method and application to solve the problems in the prior art.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions: The preparation method of the high-elongation and tensile-strength functional current collector comprises the following steps: Step 1: Put polyvinyl chloride, zinc stearate-2, calcium zinc stabilizer and plasticizer into the mixer according to the mass fraction to obtain a premix; then heat melt, filter extrusion, cast sheet, longitudinal stretching and transverse stretching to the premix in sequence, and after heat treatment, cool and roll up to obtain a modified polyvinyl chloride film; Step 2: After the modified polyvinyl chloride film surface prepared in step 1 is magnetron sputtered with a copper layer, water electroplating is performed, and the copper tank, water washing tank, anti-oxidation tank and drying tank are sequentially transferred to obtain the finished product.

[0006] More preferably, the premix in step 1 includes the following mass parts of raw materials: 100-120 parts of polyvinyl chloride, 1-4 parts of zinc stannate-2, 3-5 parts of calcium zinc stabilizer and 10-30 parts of plasticizer; More preferably, the working conditions of magnetron sputtering in step 2 include: vacuum degree of 4.0*10 -3 Pa, main roller cooling temperature of -20℃, winding speed of 10m / min, target base distance of 80-100mm, total power of single side sputtering of 100-110KW, argon flow rate of 200sccm, deep cooling refrigeration temperature of -130~-150℃, magnetic field intensity of 500GS; More preferably, the water electroplating line speed is 3m / min, the total current of the copper tank is 3500A, and the current of the anti-oxidation tank is 2A; Among them, deionized water is used as the solvent in the copper tank, including 70-130g / L copper sulfate, 100-140g / L sulfuric acid, 50-70ppm hydrochloric acid, 1-4mL / L brightener, 2-5mL / L leveling agent; the concentration of the anti-oxidation tank is 0.2-2g / L; The thickness of the modified polyvinyl chloride film is 4-6μm; the thickness of the magnetron sputtered copper layer is 10-50nm; the thickness of the water electroplated copper layer and the anti-oxidation layer is 900-950nm in total; More preferably, the particle size of zinc stannate-2 includes D50 of 1.0-3.0μm and D90 of 5-8μm; More preferably, the plasticizer is one or a combination of dioctyl phthalate, dibutyl phthalate, poly-1,2-propylene glycol adipate; More preferably, the plasticizer is a cashew phenolic plasticizer; the preparation steps of the cashew phenolic plasticizer are as follows: Step s1: Mix cashew phenol, paraformaldehyde and isopropyl alcohol amine, incubate at 80-85℃ for 6-10h, after vacuum distillation, mix with formic acid, ethyl acetate and p-toluenesulfonic acid, warm to 50-55℃, add hydrogen peroxide, incubate at 60℃ for 3-4h, separate and vacuum distill to obtain an intermediate; Step s2: Take the intermediate prepared in step s1 and mix with stannous isooctoate and ε-caprolactone, stir at 120℃ for 24h under inert atmosphere, then transfer to methanol to precipitate the polymer, vacuum dry to obtain the cashew phenolic plasticizer; The mass ratio of cardanol, paraformaldehyde and isopropanolamine in step s1 is 1: (0.5-0.8): 0.3; the dosage ratio of cardanol, formic acid, p-toluenesulfonic acid and hydrogen peroxide is 0.1 mol: 25 g: 0.8 g: (0.3-0.5) mol. The mass ratio of the intermediate, isooctanoic acid stannous salt and epsilon-caprolactone in step s2 is 10 g: 0.03 g: (0.25-0.30) mol. A lithium battery comprising the high-elongation and tensile-strength functional current collector prepared by the preparation method.

[0007] Compared with the prior art, the present application has the following beneficial effects: 1. The present application provides a preparation method of a high-elongation and tensile-strength functional current collector, which improves the tensile strength and elongation by modifying the functional current collector substrate. The main steps include: modifying polyvinyl chloride by blending with zinc stannate-2, calcium-zinc stabilizer and plasticizer, melt extruding a cast sheet, stretching and winding to obtain a modified polyvinyl chloride film; and sequentially preparing a copper layer on the surface of the film by magnetron sputtering and electroplating to obtain the functional current collector. 2. The modified polyvinyl chloride film is added with zinc stannate of different low-size particle diameters to improve the intermolecular force between polymers through heterogeneous nucleation of zinc stannate, thereby improving the tensile strength and bringing about certain flame retardation effect. The plasticizer is added with cardanol plasticizer, which is non-toxic and environmentally friendly as a plasticizer and has good application prospect. The cardanol is introduced with hydroxyl, amino and epoxidation to improve the compatibility. Then, the plasticizer is polymerized with caprolactone to connect with polycaprolactone, thereby reducing the migration of the plasticizer and improving the compatibility, the tensile strength and the elongation at break of the base film. DETAILED DESCRIPTION

[0008] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0009] In the experiment, polyvinyl chloride (PVC) is SG5 premium product, purchased from Xinjiang Zhongtai Chemical Co., Ltd.; zinc stannate-2 (Zn2SnO4-2) has a D50 of 3.0 μm and a D90 of 5.7 μm, both purchased from Henan Tudao Ge Industrial Co., Ltd.; calcium-zinc stabilizer (Ca-Zn) has a model number of Mark 6796 and is purchased from Galata Chemicals GmbH, Germany; dioctyl phthalate (DOP) is analytical pure and is purchased from Tianjin Jiayu Fine Chemical Co., Ltd.; paraformaldehyde is analytical pure and is purchased from Shanghai Aladdin; The brightener in the copper tank is sodium phenyldithiopropane sulfonate, the leveling agent is 4-benzoylpyridine; the antioxidant tank water is chromic anhydride; Embodiment 1: The embodiment provides a preparation method of a functional current collector, comprising the following steps: Step 1: 100 parts of polyvinyl chloride, 4 parts of zinc stannate-2, 5 parts of calcium zinc stabilizer and 30 parts of dioctyl phthalate are weighed by mass fraction, and are sequentially put into a high-speed mixer for preliminary mixing to obtain a premix; the premix is heated to 180 DEG C for melting, filtered by a metering pump and extruded from a die, and is cast onto a casting knife and cooled at 30 DEG C to form a thick sheet; longitudinal stretching and transverse stretching are performed, the stretched film is placed in an oven at 80 DEG C for heat treatment, and then is cooled in a platform area, enters a winding system through a traction system for film winding to obtain a modified polyvinyl chloride film with a thickness of 4.5 microns; wherein the longitudinal stretching is preheated at 70 DEG C, stretched at 110 DEG C with a stretching ratio of 3:1, and cooled at 40 DEG C after stretching is completed; the transverse stretching is preheated at 80 DEG C, stretched at 110 DEG C with a stretching ratio of 3:1, and cooled at 40 DEG C after stretching is completed; Step 2: a mechanical pump, a Roots pump and a molecular pump are used to pump to a local vacuum degree of 4.0*10 -3 Pa, the main roller cooling temperature is-20 DEG C, the winding speed is 10 m / min, the target base distance is 100 mm, the total power of single-side sputtering is 110 KW, the argon flow rate is 200 sccm, the cryogenic refrigeration temperature is-130 DEG C, and the magnetic field intensity is 500 GS; a copper layer is magnetron sputtered on the modified polyvinyl chloride film prepared in step 1, a magnetic control base film with a square resistance of 1 omega is obtained, water electroplating is performed, the linear speed is set to 3 m / min, and then the copper tank, the water washing tank, the 2A antioxidant tank and the drying tank are sequentially transferred to obtain a finished product; In the copper tank, deionized water is used as a solvent, and the copper sulfate is 120 g / L, the sulfuric acid is 100 g / L, the hydrochloric acid is 70 ppm, the brightener is 3 mL / L, and the leveling agent is 3 mL / L; the concentration of the water in the antioxidant tank is 1 g / L; The thickness of the magnetron sputtered copper layer is 50 nm, and the total thickness of the water electroplated copper layer and the oxidation layer is 950 nm. Embodiment 2: The embodiment 2 is basically the same as the embodiment 1, and the difference lies in that the parts of zinc stannate-2 are adjusted to 3 parts; the specific steps are as follows: Step 1: 100 parts of polyvinyl chloride, 3 parts of zinc stannate-2, 5 parts of calcium zinc stabilizer and 30 parts of dioctyl phthalate are weighed by mass fraction, and are sequentially put into a high-speed mixer for preliminary mixing to obtain a premix; the premix is then heated to 180℃ for melting, filtered by a metering pump and extruded from a die to a casting knife, cooled at 30℃ to form a thick sheet; longitudinal and transverse stretching is then performed, the stretched film is placed in an oven at 80℃ for heat treatment, cooled through a platform area, enters a winding system through a traction system for film winding to obtain a modified polyvinyl chloride film with a thickness of 4.5μm; wherein the longitudinal stretching is preheated at 70℃, stretched at 110℃ according to a stretching ratio of 3:1, and cooled at 40℃ after stretching is completed; the transverse stretching is preheated at 80℃, stretched at 110℃ according to a stretching ratio of 3:1, and cooled at 40℃ after stretching is completed; Step 2: a mechanical pump, a Roots pump and a molecular pump are used to pump to a local vacuum degree of 4.0×10 -3 Pa, the main roller cooling temperature is -20℃, the winding speed is 10m / min, the target base distance is 100mm, the total power of single-sided sputtering is 110KW, the argon flow rate is 200sccm, the cryogenic refrigeration temperature is -130℃, the magnetic field strength is 500GS, a copper layer is magnetron sputtered on the modified polyvinyl chloride film prepared in step 1, and the magnetron base film is then subjected to water electroplating, a linear speed of 3m / min is set, and the film is sequentially transferred to a 3500A copper tank, a water washing tank, a 2A anti-oxidation tank and a drying tank to obtain a finished product; In the copper tank, deionized water is used as a solvent, and the copper tank contains 120g / L of copper sulfate, 100g / L of sulfuric acid, 70ppm of hydrochloric acid, 3mL / L of brightener and 3mL / L of leveling agent; the concentration of the anti-oxidation tank is 1g / L; The thickness of the magnetron sputtered copper layer is 50nm, and the total thickness of the water electroplated copper layer and the oxidation layer is 950nm. Example 3: substantially the same as example 1, except that the parts of zinc stannate-2 are adjusted to 2 parts; the specific steps are as follows: Step 1: 100 parts of polyvinyl chloride, 2 parts of zinc stannate-2, 5 parts of calcium zinc stabilizer and 30 parts of dioctyl phthalate are weighed by mass fraction, and are sequentially put into a high-speed mixer for preliminary mixing to obtain a premix; the premix is then heated to 180℃ for melting, filtered by a metering pump and extruded from a die to a casting knife, cooled at 30℃ to form a thick sheet; longitudinal and transverse stretching is then performed, the stretched film is placed in an oven at 80℃ for heat treatment, cooled through a platform area, enters a winding system through a traction system for film winding to obtain a modified polyvinyl chloride film with a thickness of 4.5μm; wherein the longitudinal stretching is preheated at 70℃, stretched at 110℃ according to a stretching ratio of 3:1, and cooled at 40℃ after stretching is completed; the transverse stretching is preheated at 80℃, stretched at 110℃ according to a stretching ratio of 3:1, and cooled at 40℃ after stretching is completed; Step 2: a mechanical pump, a Roots pump and a molecular pump are used to pump to a local vacuum degree of 4.0×10 -3 Pa, the main roller cooling temperature is -20℃, the winding speed is 10m / min, the target base distance is 100mm, the total power of single-sided sputtering is 110KW, the argon flow rate is 200sccm, the cryogenic refrigeration temperature is -130℃, the magnetic field strength is 500GS, a copper layer is magnetron sputtered on the modified polyvinyl chloride film prepared in step 1, and the magnetron base film is then subjected to water electroplating, a linear speed of 3m / min is set, and the film is sequentially transferred to a 3500A copper tank, a water washing tank, a 2A anti-oxidation tank and a drying tank to obtain a finished product; In the copper tank, deionized water is used as a solvent, and the copper tank contains 120g / L of copper sulfate, 100g / L of sulfuric acid, 70ppm of hydrochloric acid, 3mL / L of brightener and 3mL / L of leveling agent; the concentration of the anti-oxidation tank is 1g / L; The thickness of the magnetron sputtered copper layer is 50nm, and the total thickness of the water electroplated copper layer and the oxidation layer is 950nm. Example 4: substantially the same as example 1, except that the parts of zinc stannate-2 are adjusted to 1 part; the specific steps are as follows: Step 1: 100 parts of polyvinyl chloride, 3 parts of zinc stannate-2, 5 parts of calcium zinc stabilizer and 30 parts of dioctyl phthalate are weighed by mass parts, and are sequentially put into a high-speed mixer for preliminary mixing to obtain a premix; the premix is heated to 180℃ for melting, filtered by a metering pump and extruded from a die, and is cast onto a casting knife and cooled at 30℃ to form a thick sheet; longitudinal stretching and transverse stretching are performed, the stretched film is placed in an oven at 80℃ for heat treatment, and then cooled in a platform area, and is wound by a traction system to obtain a modified polyvinyl chloride film with a thickness of 4.5μm; wherein the longitudinal stretching is preheated at 70℃, stretched at 110℃ with a stretching ratio of 3:1, and cooled at 40℃ after stretching; the transverse stretching is preheated at 80℃, stretched at 110℃ with a stretching ratio of 3:1, and cooled at 40℃ after stretching; Step 2: a mechanical pump, a Roots pump and a molecular pump are used to pump to a local vacuum degree of 4.0×10 -3 Pa, the cooling temperature of the main roller is -20℃, the winding speed is 10m / min, the target base distance is 100mm, the total power of single-sided sputtering is 110KW, the argon flow rate is 200sccm, the cryogenic refrigeration temperature is -130℃, and the magnetic field strength is 500GS; a copper layer is sputtered on the surface of the modified polyvinyl chloride film prepared in step 1 by magnetron sputtering, and the obtained magnetron base film is subjected to water electroplating; the linear speed is set to 3m / min, and the obtained product is sequentially transferred to a 3500A copper tank, a water washing tank, a 2A anti-oxidation tank and a drying tank; In the copper tank, deionized water is used as the solvent, and the copper tank contains 120g / L of copper sulfate, 100g / L of sulfuric acid, 70ppm of hydrochloric acid, 3mL / L of brightener and 3mL / L of leveling agent; the concentration of the anti-oxidation tank is 1g / L; The thickness of the copper layer sputtered by the magnetron is 50nm, and the total thickness of the copper layer and the oxidation layer electroplated by water is 950nm. Example 5: basically the same as example 1, the difference is that the dioctyl phthalate is replaced by cardanol-based plasticizer; the specific steps are as follows: Step 1: 100 parts of polyvinyl chloride, 4 parts of zinc stannate-2, 5 parts of calcium zinc stabilizer and 30 parts of cashew phenol-based plasticizer were weighed by mass fraction, and were sequentially put into a high-speed mixer for preliminary mixing to obtain a premix; the premix was then heated to 180℃ for melting, filtered by a metering pump and extruded from a die to a casting knife, and was cooled at 30℃ to form a thick sheet; longitudinal and transverse stretching was then performed, the stretched film was placed in an oven at 80℃ for heat treatment, and was cooled in a platform area, then entered a winding system through a traction system for film winding to obtain a modified polyvinyl chloride film with a thickness of 4.5μm; wherein the longitudinal stretching was preheated at 70℃, stretched at 110℃ with a stretching ratio of 3:1, and cooled at 40℃ after stretching; the transverse stretching was preheated at 80℃, stretched at 110℃ with a stretching ratio of 3:1, and cooled at 40℃ after stretching; Step 2: a mechanical pump, a Roots pump and a molecular pump were used to pump to a local vacuum degree of 4.0×10 -3 Pa, the main roller cooling temperature was -20℃, the winding speed was 10m / min, the target base distance was 100mm, the total power of single-side sputtering was 110KW, the argon flow rate was 200sccm, the cryogenic refrigeration temperature was -130℃, and the magnetic field intensity was 500GS; a copper layer was magnetron sputtered on the modified polyvinyl chloride film prepared in step 1, and the obtained magnetron base film was then subjected to water electroplating; the linear speed was set to 3m / min, and the film was sequentially transferred to a 3500A copper tank, a water washing tank, a 2A anti-oxidation tank and a drying tank to obtain a finished product; In the copper tank, deionized water was used as a solvent, and the copper tank contained 120g / L copper sulfate, 100g / L sulfuric acid, 70ppm hydrochloric acid, 3mL / L brightener and 3mL / L leveling agent; the concentration of the anti-oxidation tank was 1g / L; The thickness of the copper layer sputtered by the magnetron was 50nm, and the total thickness of the copper layer and the oxidation layer electroplated by water was 950nm; The preparation steps of the cashew phenol-based plasticizer were as follows: Step s1: 10g of cashew phenol, 7.45g of polyformaldehyde and 2.98g of isopropyl alcohol amine were mixed, and the mixture was reacted at 80℃ for 8h; after vacuum distillation, the mixture was mixed with 8.27g of formic acid, 200mL of ethyl acetate and 0.03g of p-toluenesulfonic acid, and then 0.58g of hydrogen peroxide was added at 50℃; the mixture was reacted at 60℃ for 3h, and then was separated and vacuum distilled to obtain an intermediate; Step s2: 10g of the intermediate prepared in step s1 was mixed with 0.03g of isooctanoic acid stannous and 30g of ε-caprolactone, and the mixture was stirred at 120℃ for 24h under a nitrogen atmosphere; the polymer was precipitated in methanol, and was vacuum dried to obtain a cashew phenol-based plasticizer. Comparative Example 1: as a control experiment of Example 1, a polypropylene film was used instead of the modified polyvinyl chloride film; the specific steps were as follows: The local vacuum degree is 4.0*10-4Pa by mechanical pump, Roots pump and molecular pump. -3 The copper layer is magnetron sputtered on the surface of the polypropylene film with a thickness of 4.5 μm, and then water plating is performed, with the line speed being set to 3 m / min, and the copper tank, water washing tank, 2A anti-oxidation tank and drying tank being sequentially passed through, to obtain the finished product. The deionized water is used as the solvent in the copper tank, and the copper tank contains 120 g / L copper sulfate, 100 g / L sulfuric acid, 70 ppm hydrochloric acid, 3 mL / L brightener and 3 mL / L leveling agent; the concentration of the medicine water in the anti-oxidation tank is 1 g / L. The thickness of the magnetron sputtered copper layer is 50 nm, and the total thickness of the water plating copper layer and the oxidation layer is 950 nm. Comparative Example 2: As a control experiment of Example 1, the modified polyvinyl chloride film is replaced by a polyethylene terephthalate film; the specific steps are as follows: The local vacuum degree is 4.0*10-4Pa by mechanical pump, Roots pump and molecular pump. -3 The copper layer is magnetron sputtered on the surface of the polypropylene film with a thickness of 4.5 μm, and then water plating is performed, with the line speed being set to 3 m / min, and the copper tank, water washing tank, 2A anti-oxidation tank and drying tank being sequentially passed through, to obtain the finished product. The deionized water is used as the solvent in the copper tank, and the copper tank contains 120 g / L copper sulfate, 100 g / L sulfuric acid, 70 ppm hydrochloric acid, 3 mL / L brightener and 3 mL / L leveling agent; the concentration of the medicine water in the anti-oxidation tank is 1 g / L. The thickness of the magnetron sputtered copper layer is 50 nm, and the total thickness of the water plating copper layer and the oxidation layer is 950 nm. Test Experiment The functional current collectors prepared in Examples 1-5 and Comparative Examples 1-2 are respectively cut into 100 mm*15 mm long strip samples, the two ends of the sample are clamped by a tensile testing machine, and the sample is stretched at a constant speed of 10 mm / min along the longitudinal axis direction of the sample until the sample is broken, and the tensile strength and elongation at break data are recorded in the following table:

[0010] Conclusion: From the above data, it can be seen that the modified polyvinyl chloride film prepared by the application has more advantages in mechanical properties than the polypropylene film and the polyethylene terephthalate film on the market; in addition, the use of plasticizer is adjusted in Example 5, further improving the mechanical properties of the product; thus, it can be seen that the functional current collector prepared by the application has high elongation and tensile strength.

[0011] It will be obvious to a person skilled in the art that, without departing from the spirit or essential characteristics of the application, the present application can be implemented otherwise than as described previously, for example, with regard to the details of construction and the arrangement of components. The disclosures and the descriptions of the embodiments are illustrative and explanatory only; they are not restrictive of the application, whose scope is defined exclusively by the following claims. Thus, consequently, only the range of equivalents to the essential features defined by the claims is intended to be encompassed by the application.

Claims

1. A method for preparing a high elongation and tensile strength functional current collector, characterized in that, Includes the following steps: Step 1: Add and mix polyvinyl chloride, zinc stannate-2, calcium zinc stabilizer and plasticizer according to the mass ratio to obtain a premix; then heat and melt the premix, filter and extrude, cast into sheets, stretch longitudinally and stretch laterally, heat treat and cool and wind up to obtain a modified polyvinyl chloride film. Step 2: A copper layer is magnetron sputtered onto the surface of the modified polyvinyl chloride film prepared in Step 1. After obtaining the magnetron base film, electroplating is performed, and the film is sequentially transferred to a copper bath, a water washing bath, an anti-oxidation bath, and a drying bath to obtain the finished product.

2. The method for preparing a high elongation and tensile strength functional current collector according to claim 1, characterized in that, The premix in step 1 includes the following raw materials by weight: 100-120 parts polyvinyl chloride, 1-4 parts zinc stannate-2, 3-5 parts calcium zinc stabilizer, and 10-30 parts plasticizer.

3. The method for preparing a high elongation and tensile strength functional current collector according to claim 1, characterized in that, The operating conditions for magnetron sputtering in step 2 include: a vacuum level of 4.0 × 10⁻⁶. -3 Pa, main roller cooling temperature is -20℃, winding speed is 10m / min, target distance is 80-100mm, total single-sided sputtering power is 100-110KW, argon flow rate is 200sccm, cryogenic cooling temperature is -130~-150℃, and magnetic field strength is 500GS.

4. The method for preparing a high elongation and tensile strength functional current collector according to claim 1, characterized in that, In step 2, the electroplating line speed is 3m / min, the total current in the copper bath is 3500A, and the current in the anti-oxidation bath is 2A.

5. The method for preparing a high elongation and tensile strength functional current collector according to claim 1, characterized in that, The copper bath uses deionized water as a solvent and contains 70-130 g / L copper sulfate, 100-140 g / L sulfuric acid, 50-70 ppm hydrochloric acid, 1-4 mL / L brightener, and 2-5 mL / L leveling agent; the concentration of the chemical solution in the antioxidant bath is 0.2-2 g / L.

6. The method for preparing a high elongation and tensile strength functional current collector according to claim 1, characterized in that, The thickness of the modified polyvinyl chloride film is 4-6 μm; the thickness of the magnetron sputtered copper layer is 10-50 nm; and the combined thickness of the electroplated copper layer and the anti-oxidation layer is 900-950 nm.

7. The method for preparing a high elongation and tensile strength functional current collector according to claim 1, characterized in that, The particle size of zinc stannate-2 includes D50 of 1.0-3.0 μm and D90 of 5-8 μm; the plasticizer is one or more combinations of dioctyl phthalate, dibutyl phthalate, and poly(1,2-propanediol) adipate.

8. The method for preparing a high elongation and tensile strength functional current collector according to claim 1, characterized in that, The plasticizer is a cashew nut phenol-based plasticizer; the preparation steps of the cashew nut phenol-based plasticizer are as follows: Step s1: Cashew phenol, paraformaldehyde and isopropanolamine are mixed and reacted at 80-85℃ for 6-10h. After vacuum distillation, they are mixed with formic acid, ethyl acetate and p-toluenesulfonic acid. Hydrogen peroxide is added at 50-55℃ and reacted at 60℃ for 3-4h. The intermediate is then separated and vacuum distilled. Step s2: Take the intermediate prepared in step s1, mix it with stannous isooctanoate and ε-caprolactone, stir and react at 120°C for 24 hours under an inert atmosphere, transfer it to methanol to precipitate the polymer, and vacuum dry to obtain cashew phenolic plasticizer.

9. The method for preparing a high elongation and tensile strength functional current collector according to claim 8, characterized in that, In step s1, the mass ratio of cashew phenol, paraformaldehyde, and isopropanolamine is 1:(0.5-0.8):0.3; the molar ratio of cashew phenol to formic acid, p-toluenesulfonic acid, and hydrogen peroxide is 0.1mol:25g:0.8g:(0.3-0.5)mol; in step s2, the mass ratio of the intermediate to stannous isooctanoate and ε-caprolactone is 10g:0.03g:(0.25-0.30)mol.

10. A lithium battery, characterized in that, The high elongation and tensile strength functional current collector is prepared by the preparation method described in any one of claims 1-9.

Images