Current collector based on negative electrode-free sodium all-solid-state battery and preparation method thereof

Abstract

The application discloses a current collector based on a negative-electrode-free sodium full-solid-state battery and a preparation method thereof, and relates to the technical field of current collectors. The current collector comprises the following steps: step 1, a copper foil surface is pretreated to obtain a pretreated copper foil; step 2, a double-target magnetron co-sputtering treatment is performed on the surface of the pretreated copper foil to form a transition layer; a current collector A is obtained; and step 3, a functional coating is coated on the surface of the current collector A under a nitrogen atmosphere, and is solidified to form a functional polymer layer; a product is obtained. The current collector prepared by the application is used for preparing a negative-electrode-free sodium full-solid-state battery, has sodium affinity, and can still maintain interface stability in the case that the battery generates heat after being cycled for multiple times.

Description

Technical Field

[0001] This invention relates to the field of current collector technology, specifically to current collectors based on sodium-free all-solid-state batteries and their preparation methods. Background Technology

[0002] With the development of the times, people are paying more and more attention to resource utilization. Compared with traditional lithium batteries, sodium batteries have stronger low-temperature stability and are easy to obtain, and have gradually become a hot research topic in new energy batteries.

[0003] Currently, researchers have developed a cathode-free sodium-solid-state battery, which mainly utilizes a solid electrolyte to directly act as both the separator and the sodium source. During the first charge, a sodium anode is formed in situ on the current collector surface. Compared to traditional sodium batteries, this technology offers advantages such as higher energy density, better safety, and a simpler manufacturing process. However, existing cathode-free sodium-solid-state batteries have several problems, particularly the lack of solid-solid contact between the solid electrolyte and the copper foil current collector. This leads to a significant increase in interfacial impedance, uneven sodium deposition, and a tendency for dendrite formation, resulting in a decrease in coulombic efficiency and severely impacting battery performance. Current technologies improve the interfacial compatibility between the current collector and the electrolyte / solid electrolyte by coating the current collector surface with a polymer layer. However, when applied to cathode-free sodium battery systems, it has been found that with increasing cycle count, internal battery temperature fluctuations intensify. The difference in thermal expansion coefficients between the polymer layer and the copper foil current collector generates interfacial thermal stress. After prolonged use, this leads to decreased interfacial stability, affecting sodium ion transport channels and reducing electrical performance.

[0004] In summary, the development of a current collector based on a sodium-free all-solid-state battery and its preparation method are of great significance in addressing the aforementioned issues. Summary of the Invention

[0005] The purpose of this invention is to provide a current collector based on a sodium-free all-solid-state battery and its preparation method, so as to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: The method for preparing a current collector based on a sodium-free all-solid-state battery includes the following steps: Step 1: Perform pretreatment on the surface of the copper foil to obtain pretreated copper foil; Step 2: Perform dual-target magnetron co-sputtering on the surface of the pretreated copper foil to form a transition layer; thus obtaining current collector A; Step 3: Under a nitrogen atmosphere, the functional coating is applied to the surface of current collector A and cured to form a functional polymer layer; the product is obtained. The transition layer is a Cu2Sb functional coating; the functional coating is obtained by mixing a fluorine-containing precursor liquid and glycidyl methacrylate.

[0007] In a further step, the pretreatment process involves conventional physical cleaning methods, including ultrasonic cleaning with acetone, anhydrous ethanol, and deionized water in sequence, followed by drying.

[0008] Ideally, the thickness of the copper foil is 9-12 μm; the thickness of the transition layer is 400-800 nm; and the thickness of the functional polymer layer is 1-2 μm.

[0009] In a further embodiment, the thickness of the transition layer and the functional polymer layer is limited in this application because: For the transition layer, if the transition layer is too thin, it will affect the uniformity and continuity of the coverage due to the island-like growth in the early stage of magnetron sputtering, resulting in uneven electron conduction paths and uneven distribution of sodium deposition nucleation sites, thus affecting the electrical performance. If the transition layer is too thick, although it can improve the difference in thermal expansion between the polymer layer and the copper foil substrate, the excessive thickness will increase the accumulation of internal stress, thus affecting the electrical performance. For functional polymer layers, if the functional polymer layer is too thin, the surface properties will be degraded (such as the micro-rough surface is prone to uncovered areas), causing local volume expansion and interface peeling during sodium deposition, resulting in local ion transport interruption or accelerated dendrite penetration, which will affect battery performance; while if it is too thick, the migration distance of sodium ions in the polymer layer will increase, the migration time will be prolonged, the accumulation of thermal stress will increase, and the electrical performance will be reduced.

[0010] In a more optimized manner, the mass ratio of fluorinated precursor liquid to glycidyl methacrylate in the raw materials of the functional coating is (60~80):1.

[0011] A more optimized method for preparing the fluorinated precursor fluid is as follows: Step 1: Modify nano-silica using fluorinated vinylsiloxane (vinyl-terminated dimethylmethyl-3,3,3-trifluoropropyl, CAS No. 68951-98-4) to obtain modified silica; Step 2: Add sodium bis(trifluoromethanesulfonyl)imide (CAS No. 91742-21-1) and modified silica to succinate, add acrylate-polyethylene glycol-amino and photoinitiator (1173 photoinitiator), and stir evenly at room temperature to obtain fluorine-containing precursor liquid.

[0012] In a more optimized manner, the raw materials of the fluorinated precursor fluid, by mass, include 10-15 parts sodium bis(trifluoromethanesulfonyl)imide, 0.5-1 parts modified silica, 2-6 parts acrylate-polyethylene glycol-amino, and 0.05-0.07 parts photoinitiator.

[0013] More optimally, the nano-silica is star-shaped mesoporous silica nanospheres with conical pore diameters of 2-3 nm and particle-filled void pore diameters of 45-55 nm.

[0014] In a further design, modified star-shaped mesoporous silica is used as a filler. Compared with traditional spherical silica, its mesoporous structure is beneficial for improving the sodium ion transport path and for loading sodium bis(trifluoromethanesulfonyl)imide. The interface formed between the interparticle voids and the polymer matrix can synergistically dissipate heat stress and improve performance.

[0015] Ideally, the molecular weight of the acrylate-polyethylene glycol-amino compound is 1500-2500. The long chain segments increase the length of the flexible chain segments in the crosslinking network, allowing the polymer layer to effectively dissipate heat stress and avoid stress concentration through chain segment conformation adjustment. Simultaneously, it contains etheroxy groups, which can coordinate with sodium ions; under thermal stress, the coordination bonds can improve the thermal stability of the interface layer itself.

[0016] In addition, its abundant ether oxygen coordination sites can form molecular forces with modified silica, further promoting the uniform dispersion of modified silica in the polymer layer and improving the structural stability and electrical properties of the polymer layer.

[0017] In a more optimized manner, the process parameters for the dual-target magnetron co-sputtering process are as follows: the gas atmosphere is argon, the gas pressure is 0.5~1Pa, the sputtering current is 0.2~0.5A, the temperature is room temperature, the power of the Cu target (high-purity copper target) is 75~135W, the power of the Sb target (high-purity antimony target) is 30~40W, and the target-substrate distance is 8~12cm.

[0018] In a further embodiment, this application utilizes dual-target magnetron co-sputtering to prepare a Cu2Sb functional coating on the surface of a pretreated copper foil. The core function of this coating is twofold: firstly, it forms a dense and continuous Cu2Sb alloy layer as a sodium-loving coating, providing high-density and uniform nucleation sites for sodium deposition, which is conducive to the formation of a continuous sodium-loving interface, thereby providing a low-impedance continuous electron conduction path for sodium ions; secondly, as a transition layer, the low coefficient of thermal expansion of Cu2Sb forms a CTE gradient transition between the copper foil and the polymer layer, buffering the thermal stress under temperature cycling and preventing the performance of the functional polymer layer from deteriorating due to thermal expansion mismatch.

[0019] In a more optimized manner, the curing process parameters are as follows: first, ultraviolet light curing is performed at a wavelength of 365nm for 10~15min at room temperature; then, thermal curing is performed at a temperature of 60~80℃ for 2~4h.

[0020] Compared with the prior art, the beneficial effects achieved by the present invention are: This application, through the setting of a transition layer and a functional polymer layer, effectively improves the thermal expansion difference between the polymer layer and the copper foil substrate while ensuring the interfacial effect between the layers in the current collector, improves the volume expansion problem under long-term battery use, and enhances sodium affinity, thereby effectively increasing the electrical performance and cycle stability of the current collector.

[0021] In this application, firstly, a continuous dense transition layer is set to form a CTE gradient transition and buffer thermal stress; secondly, a functional polymer layer is formed by setting a fluorine-containing component with high thermal stability. Compared with conventional functional polymer layers, no additives such as iodine-containing compounds that are prone to failure at high temperatures are set. Instead, the fluorine-containing component is used to coordinate and conduct sodium ions to further improve sodium affinity. The star-shaped mesoporous silica is used to further improve the thermal stability of the polymer layer itself, thereby comprehensively improving the electrical performance and cycle stability of the current collector.

[0022] In addition, this application forms a UV-cured polymer through free radical polymerization, followed by further thermal curing using amino epoxy groups, resulting in a dual curing effect. This is beneficial for improving the crosslinking density and interfacial adhesion of the polymer layer, reducing the accumulation of interfacial thermal stress between the polymer layer and the copper foil current collector due to the difference in thermal expansion coefficients, and simultaneously constructing a more stable ion transport channel, thereby improving the electrical performance and cycle stability of the current collector. Detailed Implementation

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1: A method for preparing a current collector based on a sodium-free all-solid-state battery, comprising the following steps: Pre-preparation: The preparation method of the fluorine-containing precursor liquid is as follows: (1) Fluorine-containing vinylsiloxane and nano-silica (star-shaped mesoporous silica nanospheres) are added to 80wt% ethanol aqueous solution at a mass ratio of 0.05:5, reacted at 60℃ for 6h, and dried to obtain modified silica; (2) 12 parts of sodium bis(trifluoromethanesulfonyl)imide and 0.8 parts of modified silica are added to succinate according to the weight, 3 parts of acrylate-polyethylene glycol-amino (molecular weight 2000) and 0.06 parts of photoinitiator are added, and stirred evenly at room temperature to obtain the fluorine-containing precursor liquid; Step 1: Pre-treat the surface of the copper foil (9μm) (ultrasonic cleaning with acetone, anhydrous ethanol, and deionized water in sequence, followed by drying) to obtain pre-treated copper foil; Step 2: Perform dual-target magnetron co-sputtering treatment on the surface of the pretreated copper foil (the process parameters for dual-target magnetron co-sputtering treatment are: argon atmosphere, gas pressure 0.8 Pa, sputtering current 0.35 A, temperature room temperature, Cu target power 100 W, Sb target power 35 W, target-substrate distance 10 cm) to form a transition layer (Cu2Sb functional coating, 400 nm); obtain current collector A; Step 3: Under a nitrogen atmosphere, the functional coating (a fluorinated precursor liquid and glycidyl methacrylate in a mass ratio of 60:1) is applied to the surface of current collector A and cured (first by ultraviolet light curing at a wavelength of 365nm for 12min at room temperature; then by thermal curing at 70℃ for 4h) to form a functional polymer layer (1μm); thus obtaining the product.

[0025] Example 2: A method for preparing a current collector based on a sodium-free all-solid-state battery, comprising the following steps: Pre-preparation: The preparation method of the fluorine-containing precursor liquid is as follows: (1) Fluorine-containing vinylsiloxane and nano-silica (star-shaped mesoporous silica nanospheres) are added to 80wt% ethanol aqueous solution at a mass ratio of 0.05:5, reacted at 60℃ for 6h, and dried to obtain modified silica; (2) 12 parts of sodium bis(trifluoromethanesulfonyl)imide and 0.8 parts of modified silica are added to succinate according to the weight, 3 parts of acrylate-polyethylene glycol-amino (molecular weight 2000) and 0.06 parts of photoinitiator are added, and stirred evenly at room temperature to obtain the fluorine-containing precursor liquid; Step 1: Pre-treat the surface of the copper foil (9μm) (ultrasonic cleaning with acetone, anhydrous ethanol, and deionized water in sequence, followed by drying) to obtain pre-treated copper foil; Step 2: Perform dual-target magnetron co-sputtering treatment on the surface of the pretreated copper foil (the process parameters for dual-target magnetron co-sputtering treatment are: argon atmosphere, gas pressure 0.8 Pa, sputtering current 0.35 A, temperature room temperature, Cu target power 100 W, Sb target power 35 W, target-substrate distance 10 cm) to form a transition layer (Cu2Sb functional coating, 500 nm); obtain current collector A; Step 3: Under a nitrogen atmosphere, the functional coating (containing a fluorinated precursor liquid and glycidyl methacrylate in a mass ratio of 65:1) is applied to the surface of current collector A and cured (first by ultraviolet light curing at a wavelength of 365nm for 12min at room temperature; then by thermal curing at 70℃ for 4h) to form a functional polymer layer (1.3μm); thus obtaining the product.

[0026] Example 3: A method for preparing a current collector based on a sodium-free all-solid-state battery, comprising the following steps: Pre-preparation: The preparation method of the fluorine-containing precursor liquid is as follows: (1) Fluorine-containing vinylsiloxane and nano-silica (star-shaped mesoporous silica nanospheres) are added to 80wt% ethanol aqueous solution at a mass ratio of 0.05:5, reacted at 60℃ for 6h, and dried to obtain modified silica; (2) 12 parts of sodium bis(trifluoromethanesulfonyl)imide and 0.8 parts of modified silica are added to succinate according to the weight, 3 parts of acrylate-polyethylene glycol-amino (molecular weight 2000) and 0.06 parts of photoinitiator are added, and stirred evenly at room temperature to obtain the fluorine-containing precursor liquid; Step 1: Pre-treat the surface of the copper foil (9μm) (ultrasonic cleaning with acetone, anhydrous ethanol, and deionized water in sequence, followed by drying) to obtain pre-treated copper foil; Step 2: Perform dual-target magnetron co-sputtering treatment on the surface of the pretreated copper foil (the process parameters for dual-target magnetron co-sputtering treatment are: argon atmosphere, gas pressure 0.8 Pa, sputtering current 0.35 A, temperature room temperature, Cu target power 100 W, Sb target power 35 W, target-substrate distance 10 cm) to form a transition layer (Cu2Sb functional coating, 600 nm); obtain current collector A; Step 3: Under a nitrogen atmosphere, the functional coating (containing a fluorinated precursor liquid and glycidyl methacrylate in a mass ratio of 70:1) is applied to the surface of current collector A and cured (first by ultraviolet light curing at a wavelength of 365nm for 12min at room temperature; then by thermal curing at 70℃ for 4h) to form a functional polymer layer (1.5μm); thus obtaining the product.

[0027] Example 4: A method for preparing a current collector based on a sodium-free all-solid-state battery, comprising the following steps: Pre-preparation: The preparation method of the fluorine-containing precursor liquid is as follows: (1) Fluorine-containing vinylsiloxane and nano-silica (star-shaped mesoporous silica nanospheres) are added to 80wt% ethanol aqueous solution at a mass ratio of 0.05:5, reacted at 60℃ for 6h, and dried to obtain modified silica; (2) 12 parts of sodium bis(trifluoromethanesulfonyl)imide and 0.8 parts of modified silica are added to succinate according to the weight, 3 parts of acrylate-polyethylene glycol-amino (molecular weight 2000) and 0.06 parts of photoinitiator are added, and stirred evenly at room temperature to obtain the fluorine-containing precursor liquid; Step 1: Pre-treat the surface of the copper foil (9μm) (ultrasonic cleaning with acetone, anhydrous ethanol, and deionized water in sequence, followed by drying) to obtain pre-treated copper foil; Step 2: Perform dual-target magnetron co-sputtering treatment on the surface of the pretreated copper foil (the process parameters for dual-target magnetron co-sputtering treatment are: argon atmosphere, gas pressure 0.8 Pa, sputtering current 0.35 A, temperature room temperature, Cu target power 100 W, Sb target power 35 W, target-substrate distance 10 cm) to form a transition layer (Cu2Sb functional coating, 700 nm); and obtain current collector A; Step 3: Under a nitrogen atmosphere, the functional coating (containing a fluorinated precursor liquid and glycidyl methacrylate in a mass ratio of 75:1) is applied to the surface of current collector A and cured (first by ultraviolet light curing at a wavelength of 365nm for 12min at room temperature; then by thermal curing at 70℃ for 4h) to form a functional polymer layer (1.8μm); thus obtaining the product.

[0028] Example 5: A method for preparing a current collector based on a sodium-free all-solid-state battery, comprising the following steps: Pre-preparation: The preparation method of the fluorine-containing precursor liquid is as follows: (1) Fluorine-containing vinylsiloxane and nano-silica (star-shaped mesoporous silica nanospheres) are added to 80wt% ethanol aqueous solution at a mass ratio of 0.05:5, reacted at 60℃ for 6h, and dried to obtain modified silica; (2) 12 parts of sodium bis(trifluoromethanesulfonyl)imide and 0.8 parts of modified silica are added to succinate according to the weight, 3 parts of acrylate-polyethylene glycol-amino (molecular weight 2000) and 0.06 parts of photoinitiator are added, and stirred evenly at room temperature to obtain the fluorine-containing precursor liquid; Step 1: Pre-treat the surface of the copper foil (9μm) (ultrasonic cleaning with acetone, anhydrous ethanol, and deionized water in sequence, followed by drying) to obtain pre-treated copper foil; Step 2: Perform dual-target magnetron co-sputtering treatment on the surface of the pretreated copper foil (the process parameters for dual-target magnetron co-sputtering treatment are: argon atmosphere, gas pressure 0.8 Pa, sputtering current 0.35 A, temperature room temperature, Cu target power 100 W, Sb target power 35 W, target-substrate distance 10 cm) to form a transition layer (Cu2Sb functional coating, 800 nm); obtain current collector A; Step 3: Under a nitrogen atmosphere, the functional coating (containing a fluorinated precursor liquid and glycidyl methacrylate in a mass ratio of 80:1) is applied to the surface of current collector A and cured (first by ultraviolet light curing at a wavelength of 365nm for 12min at room temperature; then by thermal curing at 70℃ for 4h) to form a functional polymer layer (2μm); thus obtaining the product.

[0029] In Examples 1-5 above, acrylate-polyethylene glycol-amino: product number ZP-41405, molecular weight 2000; star-shaped mesoporous silica nanospheres: conical pore diameter 2.9nm, particle filling void pore diameter 50nm, average size: 80nm, the rest are commercially available.

[0030] Comparative Example 1: The molecular weight of acrylate-polyethylene glycol-amino was adjusted to 350 (acrylate-polyethylene glycol-amino: catalog number ZP-41401, molecular weight 350); the rest was the same as in Example 3.

[0031] Comparative Example 2: The star-shaped mesoporous silica nanospheres were adjusted to spherical silica nanospheres (particle size 80 nm); the rest were the same as in Example 3.

[0032] Comparative Example 3: The transition layer was 1500 nm thick; the rest was the same as in Example 3.

[0033] Comparative Example 4: The functional polymer layer is too thin (0.5 μm); the rest is the same as in Example 3.

[0034] Comparative Example 5: Single transition layer; otherwise the same as Example 3.

[0035] Comparative Example 6: Single-functional polymer layer; otherwise the same as Example 3.

[0036] Comparative Example 7: The modified silica in the fluorine-containing precursor fluid was adjusted to iodide; the rest was the same as in Example 3; Preparation of iodide: Sodium iodide and elemental iodine were mixed at a molar ratio of 1:1 and ball-milled for 6 hours to obtain iodide.

[0037] The current collectors prepared in Examples 1-5 and Comparative Examples 1-7 were used to prepare sodium-free all-solid-state batteries; The fabrication process of a sodium-free all-solid-state battery is as follows: Preparation of positive electrode sheet: (1) The positive electrode active material (sodium vanadium phosphate (NVP) sodium ion battery positive electrode material model: NVP-20um), conductive agent (Super P, conductive carbon black), and binder PVDF (polyvinylidene fluoride) are added to N-methylpyrrolidone and mixed in a mass ratio of 7:2:1 to obtain the positive electrode slurry; (2) Coated onto the surface of aluminum foil with a loading of about 2 mg / cm², dried to obtain a positive electrode sheet; Na5SmSi4O 12 Solid electrolytes, prepared using conventional techniques: In the process, 1.52 parts by weight of sodium carbonate, 1 part by weight of samarium trioxide, and 1.38 parts by weight of silicon dioxide were used as raw materials. The mixture was ball-milled at 600 rpm for 15 hours, then mixed, dried at 80°C for 12 hours, and calcined at 800°C for 8 hours. The resulting powder was then pressed into shape under 300 MPa and sintered at 900°C to obtain Na5SmSi4O. 12 Solid electrolyte; Battery assembly: (1) Place the current collectors prepared in Examples 1-5 and Comparative Examples 1-7 at the bottom of the battery mold, with the functional polymer layer facing upwards, and then place Na5SmSi4O 12 The solid electrolyte is placed above the current collector (at one end of the functional polymer layer), in Na5SmSi4O 12 Functional coatings are applied to the surface of solid electrolytes. (2) Place the positive electrode sheet (the end coated with positive electrode slurry) on the interface of the functional coating, press lightly to make the functional coating wet the interface, first perform ultraviolet curing at a wavelength of 365nm for 12min at room temperature; then perform thermal curing at a temperature of 70℃ for 3h, seal the battery mold to obtain a sodium-free all-solid-state battery.

[0038] Performance testing: Current density set to 1.0 mA / cm² 2 After 2500 cycles, the coulombic efficiency (discharge capacity / charge capacity × 100%) and capacity retention rate (discharge capacity after cycle / discharge capacity before cycle × 100%) were obtained. The electrical performance of the sodium-free all-solid-state batteries prepared in Examples 1-5 and Comparative Examples 1-7 was tested accordingly; the test results are shown in Table 1. Table 1

[0039] Conclusion: As shown in Table 1 above, the battery with current collector prepared in this application has good electrical performance. Comparative Example 1 shows that adjusting the molecular weight of acrylate-polyethylene glycol-amino to 350 results in shorter chain segments, which easily lead to stress concentration and decreased electrical performance. Comparative Example 2 shows that changing the star-shaped mesoporous silica nanospheres to spherical silica nanospheres reduces the sodium ion transport path, resulting in decreased electrical performance. Comparative Example 3 shows that an excessively thick transition layer (1500 nm) increases internal stress accumulation, leading to decreased electrical performance. Comparative Example 4 shows that an excessively thin functional polymer layer (0.5 μm) results in uneven electron conduction paths and uneven distribution of sodium deposition nucleation sites, leading to decreased electrical performance. Comparative Example 5 shows that a single transition layer lacks elastic buffering, resulting in decreased electrical performance. Comparative Example 6 shows that a single functional polymer layer exhibits CTE mismatch, leading to decreased electrical performance. Comparative Example 7 shows that iodides are prone to thermal failure, resulting in decreased electrical performance.

[0040] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a current collector based on a sodium-free all-solid-state battery, characterized in that: Includes the following steps: Step 1: Perform pretreatment on the surface of the copper foil to obtain pretreated copper foil; Step 2: Perform dual-target magnetron co-sputtering on the surface of the pretreated copper foil to form a transition layer; Current collector A is obtained; Step 3: Under a nitrogen atmosphere, apply the functional coating to the surface of current collector A and cure it to form a functional polymer layer; Obtain the product; The transition layer is a Cu2Sb functional coating; the functional coating is obtained by mixing a fluorine-containing precursor liquid and glycidyl methacrylate.

2. The method for preparing the current collector based on a sodium-free all-solid-state battery according to claim 1, characterized in that: The thickness of the copper foil is 9~12μm; the thickness of the transition layer is 400~800nm; and the thickness of the functional polymer layer is 1~2μm.

3. The method for preparing the current collector based on a sodium-free all-solid-state battery according to claim 1, characterized in that: In the raw materials of the functional coating, the mass ratio of fluorinated precursor liquid to glycidyl methacrylate is (60~80):

1.

4. The method for preparing the current collector based on a sodium-free all-solid-state battery according to claim 1, characterized in that: The preparation method of the fluorine-containing precursor fluid is as follows: Step 1: Modify nano-silica using fluorinated vinylsiloxanes to obtain modified silica; Step 2: Add sodium bis(trifluoromethanesulfonyl)imide and modified silica to succinate, then add acrylate-polyethylene glycol-amino and photoinitiator, and stir evenly at room temperature to obtain a fluorinated precursor liquid.

5. The method for preparing the current collector based on a sodium-free all-solid-state battery according to claim 4, characterized in that: The raw materials of the fluorinated precursor fluid, by mass, include 10-15 parts sodium bis(trifluoromethanesulfonyl)imide, 0.5-1 parts modified silica, 2-6 parts acrylate-polyethylene glycol-amino, and 0.05-0.07 parts photoinitiator.

6. The method for preparing the current collector based on a sodium-free all-solid-state battery according to claim 4, characterized in that: The nano-silica is star-shaped mesoporous silica nanospheres with conical pores having a diameter of 2-3 nm and particles filling voids with a pore size of 45-55 nm.

7. The method for preparing the current collector based on a sodium-free all-solid-state battery according to claim 4, characterized in that: The molecular weight of the acrylate-polyethylene glycol-amino compound is 1500~2500.

8. The method for preparing the current collector based on a sodium-free all-solid-state battery according to claim 1, characterized in that: The process parameters for the dual-target magnetron co-sputtering process are as follows: argon atmosphere, gas pressure 0.5~1Pa, sputtering current 0.2~0.5A, temperature room temperature, Cu target power 75~135W, Sb target power 30~40W, and target-substrate distance 8~12cm.

9. The method for preparing the current collector based on a sodium-free all-solid-state battery according to claim 1, characterized in that: The curing process parameters are as follows: first, ultraviolet light curing is performed at a wavelength of 365nm for 10-15 minutes at room temperature; then, thermal curing is performed at a temperature of 60-80℃ for 2-4 hours.

10. The current collector prepared by the method for preparing a sodium-free all-solid-state battery according to any one of claims 1 to 9.

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