Preparation method of electrodeposited aluminum based on reverse pulse deposition technology

Abstract

The invention relates to the technical field of electro-deposited aluminum, in particular to a preparation method of electro-deposited aluminum based on a reverse pulse deposition technology, which comprises the following steps: step 1, mixing anhydrous aluminum bromide and xylene, and stirring under the protection of inert gas until the mixture is dissolved to obtain a non-aqueous electrolyte solution; step 2, adding polyethylene glycol into the non-aqueous electrolyte solution, and stirring until the polyethylene glycol is uniformly dispersed to obtain a non-aqueous electrolyte solution containing the polyethylene glycol; 3, putting the cathode substrate into a non-aqueous electrolyte solution containing polyethylene glycol, and carrying out aluminum electro-deposition by adopting pulse reverse current; and 4, after the electro-deposition is finished, taking out the cathode substrate, cooling under the protection of inert gas, carrying out ultrasonic cleaning with absolute ethyl alcohol, and carrying out vacuum drying to obtain the aluminum deposition layer. The aluminum deposition layer prepared by the method has the advantages of grain refinement, smooth surface, compactness and uniformity.

Description

Technical Field

[0001] This invention relates to the field of aluminum electrodeposition technology, specifically to a method for preparing aluminum electrodeposited using reverse pulse deposition technology. Background Technology

[0002] With the rapid development of the new energy industry and electronic information technology, the performance requirements of electrochemical energy storage systems such as lithium-ion batteries and sodium-ion batteries are becoming increasingly stringent. Cycle life, safety performance, and energy density have become key indicators for measuring the overall performance of batteries. As an important component of battery electrodes, the current collector's main function is to collect the current generated by the active material and output it externally. Its structural design and material selection directly affect the battery's internal resistance, specific energy, and thermal stability.

[0003] Currently, commercial lithium-ion and sodium-ion batteries widely use copper or aluminum foil as current collector materials for their positive and negative electrodes. Although these metal foils have mature manufacturing processes and good conductivity, their high density and cost have, to some extent, limited further improvements in battery energy density and reductions in manufacturing costs. To overcome these bottlenecks, functional current collector materials have emerged and demonstrated significant application advantages. Functional current collectors typically exhibit a "sandwich" multilayer structure, with a lightweight polymer material (such as polyethylene terephthalate, polypropylene, etc.) in the middle layer and conductive metal layers (such as aluminum or copper) deposited on both sides. This structural design not only retains the conductivity of the metal layers but also effectively reduces the overall mass of the current collector by utilizing the low density of the polymer layers, thereby improving the battery's mass energy density. Furthermore, the thin metal layer on the surface of the functional current collector makes it easier to melt or break during thermal runaway, thus severing the electrical connection between the active material and the current collector, inhibiting the spread of thermal runaway, and improving battery safety.

[0004] In the fabrication of metal layers for functional current collectors, electrodeposition methods have attracted widespread attention due to their high process controllability and suitability for large-scale production. Among these, electrodeposition technology based on the aluminum bromide-organic solvent system can achieve aluminum metal layer deposition under non-aqueous conditions, making it suitable for water-sensitive substrate materials. However, existing research and practice show that when using the aluminum bromide-xylene system alone for electrodeposition, the resulting aluminum deposits often suffer from coarse grains and poor surface smoothness, and the deposition efficiency needs further improvement. Although some studies have attempted to optimize deposition quality by adding grain refiners, adjusting current density, or changing the deposition waveform, there are no systematic reports on combining polyethylene glycol as an additive with pulsed reverse current technology to achieve synergistic improvement in the microstructure control and deposition efficiency of aluminum deposits.

[0005] In summary, developing an improved electrodeposition method based on reverse pulse deposition technology, using the aluminum bromide-xylene system as a foundation, introducing functional additives and optimizing the current mode, is of great significance for the controllable preparation of high-performance aluminum deposition layers and for promoting the application of functional current collectors in next-generation high-energy-density batteries. Summary of the Invention

[0006] The purpose of this invention is to overcome the defects of existing aluminum bromide electrodeposition technology and provide a highly efficient electrodeposition method that can significantly refine the grain size of the deposited layer, suppress dendrite formation, improve surface uniformity and density, and avoid hydrogen evolution and solvent decomposition problems, so as to solve the problems proposed in the prior art.

[0007] To achieve the above objectives, the present invention provides the following technical solution: Step 1: Mix anhydrous aluminum bromide and xylene, and stir until dissolved under inert gas protection to obtain a non-aqueous electrolyte solution; Step 2: Add polyethylene glycol to the non-aqueous electrolyte solution and stir until it is evenly dispersed to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Place the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using a pulsed reverse current; Step 4: After electrodeposition, the cathode substrate is removed, cooled under inert gas protection, ultrasonically cleaned with anhydrous ethanol, and vacuum dried to obtain the aluminum deposition layer.

[0008] Preferably, the anhydrous aluminum bromide has a mass percentage concentration of 42% to 44% in the non-aqueous electrolyte solution.

[0009] In the above technical solution, xylene is chosen as the most suitable solvent mainly because its high molar conductivity ensures that the electrolyte system maintains stable conductivity. At the same time, this solvent effectively avoids the severe hydrogen evolution or solvent disproportionation decomposition problems commonly found in other solvents such as alcohols and esters, thus providing a more stable chemical environment for the electrodeposition process.

[0010] Preferably, the molecular weight of the polyethylene glycol is 2000~10000; and the ratio of polyethylene glycol to non-aqueous electrolyte solution in the polyethylene glycol-containing non-aqueous electrolyte solution is 0.05~0.1g:1L.

[0011] Preferably, the polyethylene glycol has a molecular weight of 4000.

[0012] In the above technical solution, polyethylene glycol with a molecular weight of 4000 is preferred because it has better dispersibility in electrolytes, a more significant inhibitory effect on grain growth, and the addition of trace amounts can ensure grain refinement while avoiding the impact of excessive additives on the conductivity of the electrolyte. Preferably, the cathode substrate is a polyethylene terephthalate film.

[0013] Preferably, the inert gas is nitrogen.

[0014] Preferably, the forward current density of the pulsed reverse current is 6~8 mA / cm². 2 The reverse current density is 2~4 mA / cm². 2 The forward energizing time is 1~5s, and the reverse energizing time is 0.2~1s.

[0015] Preferably, the working conditions for the pulsed reverse current electrodeposition of aluminum are a temperature of 25~40℃ and a time of 30~120min.

[0016] In the above technical solution, the forward current density is 6~8 mA / cm². 2 This parameter can effectively prevent excessive dendrite growth under high current density; the electrodeposition temperature is 25~40℃, which can ensure the stability of xylene and avoid excessive solvent evaporation or abnormal system viscosity.

[0017] Preferably, the cooling temperature is 20~25℃.

[0018] Preferably, the anhydrous ethanol ultrasonic cleaning is performed 2 to 3 times, each time for 5 to 10 minutes.

[0019] Preferably, the working conditions for vacuum drying are a temperature of 50~60℃ and a time of 20~30min.

[0020] Compared with the prior art, the beneficial effects of the present invention are: 1. The present invention describes a method for preparing aluminum by electrodeposition based on reverse pulse deposition technology, which can significantly refine the grains of the deposited layer during aluminum electrodeposition, suppress dendrite formation, improve surface uniformity and density, and avoid hydrogen evolution and solvent decomposition.

[0021] 2. The present invention describes a method for preparing aluminum by electrodeposition based on reverse pulse deposition technology. The core of this method involves aluminum bromide dimer gaining electrons on the cathode surface, dissociating, and depositing as metallic aluminum. During the reaction, a non-aqueous system ensures high purity of the deposited aluminum. Polyethylene glycol acts as an interfacial adsorbent; the ether radical groups in its molecular chain selectively adsorb onto active sites on the cathode surface through coordination. It does not participate in the electrode reaction but inhibits tip discharge and abnormal grain growth through steric hindrance, replacing traditional inorganic additives to avoid co-deposition of impurities. Simultaneously, the introduction of a reverse pulse current causes the cathode to undergo the aforementioned reduction reaction during the forward pulse to achieve rapid aluminum deposition. During the reverse pulse, preferential anodic dissolution occurs at microscopic protrusions, thereby smoothing the interface while restoring the ion concentration gradient in the cathode region. The reverse pulse mode, through a "deposition-stripping" cycle, synergistically refines the grains and improves the density and smoothness of the deposited layer.

[0022] 3. The present invention describes a method for preparing aluminum by electrodeposition based on reverse pulse deposition technology. In the forward pulse phase, polyethylene glycol preferentially adsorbs onto high-energy active sites on the cathode surface through ether oxygen groups, utilizing the steric hindrance effect to suppress tip discharge and abnormal growth of aluminum crystal nuclei, inducing the formation of a fine-grained structure. In the reverse pulse phase, the charge on the electrode surface is reversed, which not only promotes selective anodic dissolution of aluminum atoms at micro-protrusions to smooth the deposition layer, but also provides rearrangement and re-adsorption motive force for polyethylene glycol molecules, repairing the adsorption layer damaged by rapid deposition. This synergistic mechanism of "suppressing coarsening during deposition and repairing adsorption during stripping" achieves dual regulation of grain refinement and interface smoothing during electrocrystallization, thereby obtaining an aluminum deposition layer with high density, excellent smoothness, and purity while maintaining high deposition efficiency. Detailed Implementation

[0023] 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] In the following specific implementation, Cathode substrate: polyethylene terephthalate film, 2 μm thick; Polyethylene glycol: molecular weight 4000; Anhydrous aluminum bromide, xylene, and anhydrous ethanol were all of analytical grade.

[0025] Example 1: A method for preparing aluminum by electrodeposition based on reverse pulse deposition technology, comprising the following steps: Step 1: Mix 43.7g of anhydrous aluminum bromide and 100mL of xylene, and stir under nitrogen protection until completely dissolved to obtain a non-aqueous electrolyte solution; Step 2: Add 0.01g of polyethylene glycol to the non-aqueous electrolyte solution and stir until it is completely dispersed and uniform to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Immerse the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using a pulsed reverse current. The operating conditions are a cathode forward current density of 8 mA / cm². 2 Reverse current density 4 mA / cm 2 The forward energizing time was 1s, the reverse energizing time was 0.2s, the electrodeposition temperature was 25℃, and the electrodeposition time was 30min. Step 4: After electrodeposition, the cathode substrate is removed, cooled to 20°C under nitrogen protection, and then ultrasonically cleaned twice with anhydrous ethanol for 5 minutes each time. It is then vacuum dried at 50°C for 20 minutes to obtain a uniform and dense aluminum deposition layer.

[0026] Example 2: A method for preparing aluminum by electrodeposition based on reverse pulse deposition technology, comprising the following steps: Step 1: Mix 43.7g of anhydrous aluminum bromide and 100mL of xylene, and stir under nitrogen protection until completely dissolved to obtain a non-aqueous electrolyte solution; Step 2: Add 0.01g of polyethylene glycol to the non-aqueous electrolyte solution and stir until it is completely dispersed and uniform to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Immerse the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using a pulsed reverse current. The operating conditions are a cathode forward current density of 7 mA / cm². 2 Reverse current density 3 mA / cm 2 The forward energizing time was 2s, the reverse energizing time was 0.3s, the electrodeposition temperature was 27℃, and the electrodeposition time was 60min. Step 4: After electrodeposition, the cathode substrate is removed, cooled to 21°C under nitrogen protection, and then ultrasonically cleaned twice with anhydrous ethanol for 6 minutes each time. It is then vacuum dried at 52°C for 22 minutes to obtain a uniform and dense aluminum deposition layer.

[0027] Example 3: A method for preparing aluminum by electrodeposition based on reverse pulse deposition technology, comprising the following steps: Step 1: Mix 43.7g of anhydrous aluminum bromide and 100mL of xylene, and stir under nitrogen protection until completely dissolved to obtain a non-aqueous electrolyte solution; Step 2: Add 0.01g of polyethylene glycol to the non-aqueous electrolyte solution and stir until it is completely dispersed and uniform to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Immerse the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using a pulsed reverse current. The operating conditions are a cathode forward current density of 6 mA / cm².2 Reverse current density 2mA / cm 2 The forward energizing time was 3s, the reverse energizing time was 0.4s, the electrodeposition temperature was 30℃, and the electrodeposition time was 80min. Step 4: After electrodeposition, the cathode substrate is removed, cooled to 23°C under nitrogen protection, and then ultrasonically cleaned three times with anhydrous ethanol for 7 minutes each time. It is then vacuum dried at 55°C for 25 minutes to obtain a uniform and dense aluminum deposition layer.

[0028] Example 4: A method for preparing aluminum by electrodeposition based on reverse pulse deposition technology, comprising the following steps: Step 1: Mix 43.7g of anhydrous aluminum bromide and 100mL of xylene, and stir under nitrogen protection until completely dissolved to obtain a non-aqueous electrolyte solution; Step 2: Add 0.01g of polyethylene glycol to the non-aqueous electrolyte solution and stir until it is completely dispersed and uniform to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Immerse the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using a pulsed reverse current. The operating conditions are a cathode forward current density of 6 mA / cm². 2 Reverse current density 2mA / cm 2 The forward energizing time was 4s, the reverse energizing time was 0.6s, the electrodeposition temperature was 35℃, and the electrodeposition time was 90min. Step 4: After electrodeposition, the cathode substrate is removed, cooled to 24°C under nitrogen protection, and then ultrasonically cleaned three times with anhydrous ethanol for 8 minutes each time. It is then vacuum dried at 57°C for 27 minutes to obtain a uniform and dense aluminum deposition layer.

[0029] Example 5: A method for preparing aluminum by electrodeposition based on reverse pulse deposition technology, comprising the following steps: Step 1: Mix 43.7g of anhydrous aluminum bromide and 100mL of xylene, and stir under nitrogen protection until completely dissolved to obtain a non-aqueous electrolyte solution; Step 2: Add 0.01g of polyethylene glycol to the non-aqueous electrolyte solution and stir until it is completely dispersed and uniform to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Immerse the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using a pulsed reverse current. The operating conditions are a cathode forward current density of 6 mA / cm². 2 Reverse current density 2mA / cm 2 The forward energizing time was 5s, the reverse energizing time was 1s, the electrodeposition temperature was 40℃, and the electrodeposition time was 30min. Step 4: After electrodeposition, the cathode substrate is removed, cooled to 25°C under nitrogen protection, and then ultrasonically cleaned three times with anhydrous ethanol for 10 minutes each time. It is then vacuum dried at 60°C for 30 minutes to obtain a uniform and dense aluminum deposition layer.

[0030] Comparative Example 1: Compared with Example 1, the pulsed reverse current was replaced with conventional direct current; Step 1: Mix 43.7g of anhydrous aluminum bromide and 100mL of xylene, and stir under nitrogen protection until completely dissolved to obtain a non-aqueous electrolyte solution; Step 2: Add 0.01g of polyethylene glycol to the non-aqueous electrolyte solution and stir until it is completely dispersed and uniform to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Place the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using conventional direct current. The operating conditions are a cathode current density of 8 mA / cm². 2 The electrodeposition temperature was 25℃ and the electrodeposition time was 30 min. Step 4: After electrodeposition, the cathode substrate is removed, cooled to 20°C under nitrogen protection, and then ultrasonically cleaned twice with anhydrous ethanol for 5 minutes each time. It is then vacuum dried at 50°C for 20 minutes to obtain a uniform and dense aluminum deposition layer.

[0031] Comparative Example 2: Compared with Example 1, polyethylene glycol was replaced with hexamethylenetetramine; Step 1: Mix 43.7g of anhydrous aluminum bromide and 100mL of xylene, and stir under nitrogen protection until completely dissolved to obtain a non-aqueous electrolyte solution; Step 2: Add 0.01g of hexamethylenetetramine to the non-aqueous electrolyte solution and stir until it is completely dispersed and uniform to obtain a non-aqueous electrolyte solution containing hexamethylenetetramine; Step 3: Immerse the cathode substrate in a non-aqueous electrolyte solution containing hexamethylenetetramine, and perform aluminum electrodeposition using a pulsed reverse current. The operating conditions are a cathode forward current density of 8 mA / cm². 2 Reverse current density 4 mA / cm 2 The forward energizing time was 1s, the reverse energizing time was 0.2s, the electrodeposition temperature was 25℃, and the electrodeposition time was 30min. Step 4: After electrodeposition, the cathode substrate is removed, cooled to 20°C under nitrogen protection, and then ultrasonically cleaned twice with anhydrous ethanol for 5 minutes each time. It is then vacuum dried at 50°C for 20 minutes to obtain a uniform and dense aluminum deposition layer.

[0032] Comparative Example 3: Compared with Example 1, xylene was replaced with anhydrous ethanol; Step 1: Mix 43.7g of anhydrous aluminum bromide and 100mL of anhydrous ethanol, and stir under nitrogen protection until completely dissolved to obtain a non-aqueous electrolyte solution; Step 2: Add 0.01g of polyethylene glycol to the non-aqueous electrolyte solution and stir until it is completely dispersed and uniform to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Immerse the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using a pulsed reverse current. The operating conditions are a cathode forward current density of 8 mA / cm². 2 Reverse current density 4 mA / cm 2 The forward energizing time was 1s, the reverse energizing time was 0.2s, the electrodeposition temperature was 25℃, and the electrodeposition time was 30min. Step 4: After electrodeposition, the cathode substrate is removed, cooled to 20°C under nitrogen protection, and then ultrasonically cleaned twice with anhydrous ethanol for 5 minutes each time. It is then vacuum dried at 50°C for 20 minutes to obtain a uniform and dense aluminum deposition layer.

[0033] Comparative Example 4: Compared to Example 1, the cathode forward current density was adjusted to 9 mA / cm². 2 ; Step 1: Mix 43.7g of anhydrous aluminum bromide and 100mL of xylene, and stir under nitrogen protection until completely dissolved to obtain a non-aqueous electrolyte solution; Step 2: Add 0.01g of polyethylene glycol to the non-aqueous electrolyte solution and stir until it is completely dispersed and uniform to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Immerse the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using a pulsed reverse current. The operating conditions are a cathode forward current density of 9 mA / cm². 2 Reverse current density 4 mA / cm 2 The forward energizing time was 1s, the reverse energizing time was 0.2s, the electrodeposition temperature was 25℃, and the electrodeposition time was 30min. Step 4: After electrodeposition, the cathode substrate is removed, cooled to 20°C under nitrogen protection, and then ultrasonically cleaned twice with anhydrous ethanol for 5 minutes each time. It is then vacuum dried at 50°C for 20 minutes to obtain a uniform and dense aluminum deposition layer.

[0034] Experiment: The cathode substrates with uniform and dense aluminum deposition layers obtained in Examples 1-5 and Comparative Examples 1-3 were used to prepare samples and tested. Grain size inspection: Observation was performed using a scanning electron microscope with reference to GB / T 6394-2017; Surface roughness inspection: It is inspected using a laser confocal microscope; All data are shown in Table 1.

[0035] Table 1

[0036] As shown in Table 1, the aluminum deposits prepared in Examples 1-5 of this invention are significantly superior to the comparative examples in terms of microstructure and surface morphology. Example 1 exhibits the best grain refinement and smoothness with an average grain size of 1.5 μm and a surface roughness of 0.12 μm. In contrast, Comparative Examples 1 (where the pulsed reverse current was replaced with conventional direct current) and 2 (where polyethylene glycol was replaced with hexamethylenetetramine) showed grain coarsening to 3.5 μm and 2.8 μm, respectively, with corresponding increases in surface roughness to 0.4 μm and 0.25 μm. This confirms that the synergistic effect between the pulsed reverse current and polyethylene glycol is key to achieving grain refinement and interface smoothness. Particularly noteworthy is that replacing xylene with anhydrous ethanol (Comparative Example 3) resulted in significant hydrogen evolution during electrodeposition, producing the worst quality deposit with numerous pores. Furthermore, the solvent began to decompose slightly (the solution turned yellow) after 10 minutes of deposition, further validating the importance of non-aqueous systems and solvent stability for the electrodeposition process. In addition, in Comparative Example 4, the forward current density was adjusted to 9 mA / cm². 2 Subsequently, the grain size and roughness also deteriorated, indicating that a reasonable range of current parameters plays a crucial role in maintaining the quality of the deposited layer. In summary, this invention successfully achieved high densification, fine grain refinement, and surface smoothing of aluminum deposited layers through the synergistic mechanism of "deposition-stripping" of polyethylene glycol interfacial adsorption regulation and pulsed reverse current.

[0037] 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 aluminum by electrodeposition based on reverse pulse deposition technology, characterized in that: Includes the following steps: Step 1: Mix anhydrous aluminum bromide and xylene, and stir until dissolved under inert gas protection to obtain a non-aqueous electrolyte solution; Step 2: Add polyethylene glycol to the non-aqueous electrolyte solution and stir until it is evenly dispersed to obtain a non-aqueous electrolyte solution containing polyethylene glycol; Step 3: Place the cathode substrate in a non-aqueous electrolyte solution containing polyethylene glycol, and perform aluminum electrodeposition using a pulsed reverse current; Step 4: After electrodeposition, the cathode substrate is removed, cooled under inert gas protection, ultrasonically cleaned with anhydrous ethanol, and vacuum dried to obtain the aluminum deposition layer.

2. The method for preparing aluminum by electrodeposition based on reverse pulse deposition technology according to claim 1, characterized in that: The anhydrous aluminum bromide has a mass percentage concentration of 42% to 44% in the non-aqueous electrolyte solution.

3. The method for preparing aluminum by electrodeposition based on reverse pulse deposition technology according to claim 1, characterized in that: The polyethylene glycol has a molecular weight of 2000~10000; the ratio of polyethylene glycol to non-aqueous electrolyte solution in the polyethylene glycol-containing solution is 0.05~0.1g:1L.

4. The method for preparing aluminum by electrodeposition based on reverse pulse deposition technology according to claim 1, characterized in that: The cathode substrate is a polyethylene terephthalate film.

5. The method for preparing aluminum by electrodeposition based on reverse pulse deposition technology according to claim 1, characterized in that: The inert gas is nitrogen.

6. The method for preparing aluminum by electrodeposition based on reverse pulse deposition technology according to claim 1, characterized in that: The forward current density of the pulsed reverse current is 6~8 mA / cm². 2 The reverse current density is 2~4 mA / cm². 2 The forward energizing time is 1~5s, and the reverse energizing time is 0.2~1s.

7. The method for preparing aluminum by electrodeposition based on reverse pulse deposition technology according to claim 1, characterized in that: The working conditions for the pulsed reverse current electrodeposition of aluminum are a temperature of 25~40℃ and a time of 30~120min.

8. The method for preparing aluminum by electrodeposition based on reverse pulse deposition technology according to claim 1, characterized in that: The cooling temperature is 20~25℃.

9. The method for preparing aluminum by electrodeposition based on reverse pulse deposition technology according to claim 1, characterized in that: The anhydrous ethanol ultrasonic cleaning is performed 2-3 times, each time for 5-10 minutes.

10. The method for preparing aluminum by electrodeposition based on reverse pulse deposition technology according to claim 1, characterized in that: The working conditions for vacuum drying are a temperature of 50~60℃ and a time of 20~30min.

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