Application of anti-corrosion commercial paint as zinc negative electrode coating in Ah-grade zinc metal soft package battery by introducing additive into anti-corrosion commercial paint

Abstract

The invention discloses an application of an anti-corrosion commercial coating as a zinc negative electrode coating in an Ah-grade zinc metal soft package battery by introducing an additive into the anti-corrosion commercial coating, and belongs to the technical field of aqueous zinc metal secondary batteries. The invention uses tallow amines as additives to be introduced into commercial coatings. Under the action of an electric field, the preferentially adsorbed tallow amine is chemically adsorbed with zinc, so that the acting force between the coating and the zinc negative electrode is enhanced, and the coating is prevented from falling off. Meanwhile, water-related side reactions are effectively inhibited through coating modification, ordered deposition of zinc ions is guided, an electric field is uniform, the effect of inhibiting dendritic crystal growth is achieved, and the electrochemical reversibility of the zinc negative electrode is improved. Therefore, the ZnZn symmetric battery assembled by using the zinc negative electrode containing the tallow amine coating circulates for 1500 hours at the current density of 2 mA cm <-2 >; the assembled ZnMnO2 button type total battery circulates for 500 circles under the current density of 1A g <-1 >; the soft package battery circulates for 15 circles under the current density of 2 mA cm <-2 >, and has the capacity of 1.0 Ah. The preparation process is simple, the effect is remarkable, the cost is low, and the requirements of environmental economic benefits are met.

Description

Technical Field

[0001] This invention relates to the field of aqueous zinc metal secondary battery technology, specifically to the application of an additive introduced into a corrosion-resistant commercial coating as a zinc negative electrode coating in Ah-level zinc metal pouch batteries. Background Technology

[0002] Aqueous zinc metal batteries are abundant in resources and have a large volumetric capacity (5855mAh cm⁻¹). -3 The advantages of zinc-metal batteries, such as their suitable redox potential (-0.76V vs. standard hydrogen potential), have sparked a research boom. However, the practical application of aqueous zinc-metal batteries still faces challenges such as side reactions related to water and dendrite growth. Since the zinc anode uses zinc metal, which is thermodynamically unstable and readily reacts with H+ in acidic electrolytes... + The reaction produces hydrogen gas, which reduces the coulombic efficiency and cycle life of the zinc anode. Therefore, enhancing the stability of the zinc anode is crucial for improving the electrochemical performance of aqueous zinc metal batteries.

[0003] To improve the stability of zinc anodes, modification strategies mainly include: (1) coating modification, (2) electrolyte optimization, and (3) membrane modification. Among these, coating modification is used to mitigate dendrite growth and side reactions. This method offers superior cost-effectiveness, ease of control, and suitability for multifunctional preparation and large-scale production. Coatings can be designed with specific functional groups that can form a stable solid-electrolyte interface with zinc. For example, functional groups can optimize Zn... 2+ The coating accelerates charge transfer kinetics, reduces nucleation overpotential, and inhibits dendritic crystal growth, effectively suppressing side reactions and corrosion. Furthermore, the coating typically exhibits excellent interfacial adaptability, maintaining strong adhesion and encapsulation of the zinc anode even under volume changes, thereby mitigating structural damage to zinc caused by expansion and contraction during charging and discharging.

[0004] This invention introduces additives into commercial anti-corrosion coatings to obtain a modified slurry, which is then coated onto the surface of a zinc anode. This accelerates the zinc ion reduction kinetics, inhibits dendrite growth and side reactions, and improves the thermodynamic stability of the zinc anode, thereby further improving the electrochemical performance of the full battery and achieving stable cycling of Ah-level zinc metal pouch batteries. Summary of the Invention

[0005] The purpose of this invention is to provide an application of a corrosion-resistant commercial coating with additives as a zinc anode coating in Ah-level zinc metal pouch batteries. By introducing tallow amine into the commercial coating as a slurry and coating the zinc anode surface, the zinc-philic functional groups undergo strong chemical adsorption with zinc, forming a protective layer. This improves the zinc content of zinc-containing batteries. 2+The reduction kinetics at the interface mitigate concentration polarization and inhibit dendrite growth. On the other hand, the protective layer effectively isolates water molecules, suppresses water-related side reactions, and improves the reversibility of the zinc anode.

[0006] To achieve the objectives of this invention, the following technical solution is adopted:

[0007] (1) Preparation of additive solution: Dissolve a certain amount of tallow amine in ethanol, sonicate until homogeneous, and obtain a concentration of 1-100 mmol / L. -1 Solution.

[0008] (2) Preparation of coating slurry: Take a certain amount of anti-corrosion coating and the solution prepared in step (1) and mix them in a certain volume ratio to obtain the slurry.

[0009] (3) Preparation of zinc metal coating: The slurry prepared in step (2) is coated onto zinc foil with a thickness of 250 micrometers using a scraper, and then placed in a vacuum drying oven at 60°C for 10 hours to obtain zinc foil with modified coating.

[0010] (4) Electrolyte preparation: A salt solution is prepared by dissolving a soluble zinc salt in deionized water, wherein the concentration of the salt solution is 2-5 mol / L. -1 .

[0011] (5) The manganese-based compound positive electrode used in the button cell is prepared by the following method: Manganese dioxide, conductive agent, and binder are mixed in a mass ratio of 8:1:1, and some solvent is added to prepare a slurry. The slurry is coated onto carbon cloth and dried in a vacuum drying oven at 60°C for 10 hours to obtain a manganese dioxide positive electrode sheet. The mass loading of the manganese-based compound positive electrode material in the manganese dioxide positive electrode sheet is 1.0–10.0 mg / cm³. -2 .

[0012] (6) The manganese-based compound positive electrode sheet used in the soft-pack battery is prepared by the following method: A certain amount of solvent is added and mixed into a dough-like consistency according to the mass ratio of manganese dioxide: conductive agent: binder = 8:1:1. The dough is then rolled onto a Ti mesh and dried in a vacuum drying oven at 60°C for 10 hours to obtain the manganese dioxide positive electrode sheet. The mass loading of the manganese-based compound positive electrode material in the manganese dioxide positive electrode sheet is 30–110 mg / cm³. -2 .

[0013] (7) Using the zinc foil prepared in step (3) as the negative electrode, the manganese dioxide positive electrode sheet prepared in step (5) as the positive electrode, and glass fiber as the separator, the electrolyte prepared in step (4) is added dropwise to assemble a button cell (CR2032 type) and its zinc storage performance is tested.

[0014] (8) Using the zinc foil prepared in step (3) as the negative electrode, the manganese dioxide positive electrode sheet prepared in step (6) as the positive electrode, and glass fiber as the separator, the electrolyte prepared in step (4) is added dropwise to assemble a soft pack battery and its zinc storage performance is tested.

[0015] The anti-corrosion coating mentioned in step (1) above is a functional coating produced by Fujian Wan'an Industrial Group.

[0016] The volume range of the anti-corrosion coating used in step (2) above is 99mL-200L.

[0017] The volume ratio of the anti-corrosion coating described in step (2) to the solution prepared in step (1) is in the range of 49-100:1.

[0018] The soluble zinc salt in step (4) above is selected from zinc sulfate, zinc trifluoromethanesulfonate, zinc acetate, zinc chloride, or zinc perchlorate.

[0019] The assembly method of the coin cell in step (7) is as follows: the zinc foil coated with the modified coating prepared in step (3) is used as the negative electrode, the manganese dioxide positive electrode sheet prepared in step (5) is used as the positive electrode, glass fiber is used as the separator, and the electrolyte in step (4) is added to assemble the coin cell.

[0020] The assembly method of the soft-pack battery described in step (8) above is as follows: the outer packaging aluminum-plastic film is 12cm×12cm in size, the single piece size of the coating-modified zinc metal negative electrode prepared in step (3) is 10cm×10cm, the single piece size of the manganese dioxide positive electrode sheet prepared in step (6) is 9cm×9cm, and the single piece size of the glass fiber separator is 11cm×11cm. The negative electrode, glass fiber separator, and manganese dioxide positive electrode sheet are stacked in sequence, and the electrolyte prepared in step (4) is introduced to assemble the soft-pack battery.

[0021] Compared with existing technologies, the present invention has the following specific advantages:

[0022] (1) Coating modification is the most promising modification method to improve the stability of zinc anode. It is simple to operate and has obvious effects.

[0023] (2) Tallow amine is a low-cost, safe, non-toxic and harmless additive with environmental and economic benefits.

[0024] (3) The anti-corrosion coating of the present invention introduces tallow amine additive, and the adsorption of zinc-loving functional groups constructs an orderly and stable protective layer, which effectively inhibits water-related corrosion reactions and hydrogen evolution reactions, and improves the electrochemical reversibility of zinc anode.

[0025] (4) Tallow amine additives are effective and practical. Symmetrical and full cells assembled with modified zinc anodes prepared using coatings containing tallow amine exhibit the advantages of long cycle life and stability. Zn||Zn symmetric cells at 2 mA cm⁻¹ -2 Cycling at current density for 1500 h; Zn||MnO2 coin cell at 1 A g -1 Cycling at current density for 500 cycles; Zn||MnO2 pouch cell at 2 mAcm -2 After 15 cycles at current density, the reversible capacity is 1.0 Ah. Attached Figure Description

[0026] Figure 1 This is a SEM image of the zinc anode obtained in Example 1 after it has been assembled into a battery and cycled.

[0027] Figure 2 This is the AFM image of the zinc anode after the coated modified zinc anode obtained in Example 1 is assembled into a battery and cycled.

[0028] Figure 3 The image shows the Tafel plots of the coated modified zinc anode and Ti obtained in Example 1, tested using a three-electrode method.

[0029] Figure 4 The image shows the LSV diagram of the coated modified zinc anode and Ti obtained in Example 1, tested using a three-electrode method.

[0030] Figure 5 The coated and modified zinc anode obtained in Example 1 was assembled into a symmetrical cell at 2 mA cm⁻¹ -2 Cyclic performance diagram at current density.

[0031] Figure 6 The Zn||MnO2 coin cell assembled with the electrolyte obtained in Example 1 was tested at 1Ag. -1 Cyclic performance at current density.

[0032] Figure 7 The Zn||MnO2 pouch cell assembled with the acidic electrolyte obtained in Example 1 operates at 2 mA cm⁻¹. -2 Cyclic performance at current density. Detailed Implementation

[0033] Example 1

[0034] 1) Weigh out 4.63 mg of tallow amine and dissolve it in 5 ml of anhydrous ethanol. Sonicate until clear and transparent to prepare a tallow amine-containing solution. 2) Take 99 ml of commercial anti-corrosion coating (functional coating, product code 3011, epoxy resin, produced by Fujian Wan'an Industrial Group) and 1 ml of the tallow amine-containing solution obtained in step 1) to prepare a slurry. Apply the slurry to zinc foil using a 250-micron scraper and dry it in a vacuum drying oven at 60°C for 10 hours to obtain modified zinc foil. The modified zinc foil has a protective layer on its surface, isolating active water molecules and inhibiting corrosion reaction. SEM images of the recycled modified zinc anode (i.e., the modified zinc foil) show that its surface remains smooth and flat, without large byproducts or dendrite formation. Figure 1 Meanwhile, the AFM spectrum test also showed that the surface of the modified zinc anode (i.e., the modified zinc foil) after cycling was uniform and flat, without large protrusions. Figure 2 The corrosion resistance of unmodified / modified zinc sheets (i.e., modified zinc foil) was compared using polarization curves. The modified zinc sheets (i.e., modified zinc foil) exhibited increased corrosion voltage and decreased corrosion current, thus better mitigating the corrosion reaction. Figure 3 Furthermore, the effect of the modified zinc foil on the hydrogen evolution reaction was tested using LSV. Using the modified zinc foil increased the hydrogen evolution overpotential and effectively suppressed hydrogen generation. Figure 4 Therefore, using modified zinc foil as both the negative and positive electrodes, and 2M zinc sulfate as the electrolyte, a Zn||Zn symmetric cell was assembled at 2 mA / cm². -2 The cycle life at current density is 1500 hours. Figure 5 Furthermore, using modified zinc foil as the negative electrode, the manganese-based compound prepared in Example 5 as the positive electrode, glass fiber as the separator, and 2M zinc sulfate electrolyte to assemble a Zn||MnO2 full cell at 1Ag -1 500 cycles at current density ( Figure 6 Furthermore, a Zn||MnO2 soft-pack full battery was prepared using modified zinc foil as the negative electrode. The outer packaging aluminum-plastic film had a size of 12cm × 12cm, the modified zinc foil negative electrode had a single-piece size of 10cm × 10cm, the manganese-based compound positive electrode sheet prepared in Example 6 had a single-piece size of 9cm × 9cm, and the glass fiber separator had a single-piece size of 11cm × 11cm. The negative electrode, separator, and positive electrode were stacked sequentially to assemble the zinc metal soft-pack battery. The battery achieved a 2mA / cm² performance. -2 After 15 cycles at current density, the capacity is 1.0 Ah. Figure 7 These results demonstrate the effectiveness and practicality of tallow amine as a zinc anode coating in Ah-level pouch cells.

[0035] Example 2

[0036] 1) Weigh out 61.72 mg of tallow amine and dissolve it in 20 ml of ethanol. Sonicate until clear and transparent to prepare a tallow amine-containing solution. 2) Take 1 L of commercial anti-corrosion coating (functional coating, product code 3011, epoxy resin, purchased from Fujian Wan'an Industrial Group) and the 20 ml of tallow amine-containing solution obtained in step 1) to prepare a slurry. Apply the slurry to zinc foil using a 250-micron scraper and dry it in a vacuum drying oven at 60°C for 10 hours to obtain modified zinc foil. The modified zinc foil has a protective layer on its surface, isolating active water molecules and inhibiting corrosion. The modified zinc foil is used as the negative electrode, the manganese-based compound obtained in Example 5 is used as the positive electrode, glass fiber is used as the separator, and 2M zinc perchlorate is used as the electrolyte to assemble a Zn||MnO2 coin cell. A Zn||MnO2 soft-pack full battery was prepared using modified zinc foil as the negative electrode. The outer packaging aluminum-plastic film was 12cm×12cm in size. The single piece size of the modified zinc foil negative electrode was 10cm×10cm. The single piece size of the manganese-based compound positive electrode sheet prepared in Example 6 was 9cm×9cm. The single piece size of the glass fiber separator was 11cm×11cm. 2M zinc perchlorate was used as the electrolyte. The zinc metal soft-pack battery was assembled by stacking the negative electrode, separator, and positive electrode in sequence.

[0037] Example 3

[0038] 1) Weigh out 1.23g of tallow amine and dissolve it in 400ml of ethanol. Sonicate until clear and transparent to prepare a tallow amine-containing solution. 2) Take 20L of commercial anti-corrosion coating (functional coating purchased from Fujian Wan'an Industrial Group, product code 3011, epoxy resin) and the 400ml tallow amine-containing solution obtained in step 1) to prepare a slurry. Apply the slurry to zinc foil using a 250-micron scraper and dry it in a vacuum drying oven at 60℃ for 10h to obtain modified zinc foil. The modified zinc foil has a protective layer on its surface, isolating active water molecules and inhibiting corrosion. The modified zinc foil is used as the negative electrode, the manganese-based compound obtained in Example 5 is used as the positive electrode, glass fiber is used as the separator, and 5M zinc trifluoromethanesulfonate is used as the electrolyte to assemble a Zn||MnO2 coin cell. A Zn||MnO2 soft-pack full battery was prepared using modified zinc foil as the negative electrode. The outer packaging aluminum-plastic film was 12cm×12cm in size. The single piece size of the modified zinc foil negative electrode was 10cm×10cm. The single piece size of the manganese-based compound positive electrode sheet prepared in Example 6 was 9cm×9cm. The single piece size of the glass fiber separator was 11cm×11cm. 5M zinc trifluoromethanesulfonate was used as the electrolyte. The zinc metal soft-pack battery was assembled by stacking the negative electrode, separator, and positive electrode in sequence.

[0039] Example 4

[0040] 1) Weigh out 6.176 g of tallow amine and dissolve it in 4 L of ethanol. Sonicate until clear and transparent to prepare a tallow amine-containing solution. 2) Take 200 L of commercial anti-corrosion coating (functional coating purchased from Fujian Wan'an Industrial Group, product code 3011, epoxy resin) and the 4 L of tallow amine-containing solution obtained in step 1) to prepare a slurry. Apply the slurry to zinc foil using a 250 μm scraper and dry it in a vacuum drying oven at 60°C for 10 h to obtain modified zinc foil. The modified zinc foil has a protective layer on its surface, isolating active water molecules and inhibiting corrosion. The modified zinc foil is used as the negative electrode, the manganese-based compound obtained in Example 5 is used as the positive electrode, glass fiber is used as the separator, and 2M zinc acetate is used as the electrolyte to assemble a Zn||MnO2 coin cell. A Zn||MnO2 soft-pack full battery was prepared using modified zinc foil as the negative electrode. The outer packaging aluminum-plastic film was 12cm×12cm in size. The single piece size of the modified zinc foil negative electrode was 10cm×10cm. The single piece size of the manganese-based compound positive electrode sheet prepared in Example 6 was 9cm×9cm. The single piece size of the glass fiber separator was 11cm×11cm. 2M zinc acetate was used as the electrolyte. The zinc metal soft-pack battery was assembled by stacking the negative electrode, separator, and positive electrode in sequence.

[0041] Example 5

[0042] Manganese-based compound cathodes used in coin cells are prepared

[0043] A slurry was prepared by mixing manganese dioxide, Super P, and PVDF at a mass ratio of 24 mg:3 mg:3 mg and adding 200 μL of NMP. The slurry was then coated onto carbon cloth and dried in a vacuum oven at 60°C for 10 hours to obtain a manganese dioxide positive electrode sheet. The mass loading of the manganese-based compound positive electrode material was 1.0–10.0 mg / cm³. -2 .

[0044] Example 6

[0045] Manganese-based compound positive electrode sheet for pouch batteries is prepared

[0046] According to the mass ratio of manganese dioxide:Super P:PVDF = 1.6g:0.6g:0.6g, 6mL of NMP was added and mixed to form a dough. The dough was rolled onto a Ti mesh and dried in a vacuum drying oven at 60℃ for 10h to obtain a manganese dioxide positive electrode sheet. The mass loading of the positive electrode sheet containing manganese-based compounds was 30-110 mg / cm³. -2 .

[0047] The above description is only a preferred embodiment of the present invention. All equivalent changes and modifications made within the scope of the claims of the present invention should be included in the scope of the present invention.

Claims

1. The application of an additive introduced into a corrosion-resistant commercial coating as a zinc negative electrode coating in Ah-level zinc metal soft-pack batteries, characterized in that, The steps are as follows: (1) Preparation of additive solution: Dissolve a certain amount of tallow amine in ethanol, sonicate until homogeneous, and obtain a concentration of 1-100 mmol / L. -1 Solution; (2) Preparation of coating slurry: Take a certain amount of anti-corrosion coating and the solution prepared in step (1) and mix them in a certain volume ratio to obtain the slurry; (3) Preparation of zinc metal coating: The slurry prepared in step (2) is coated onto zinc foil with a thickness of 250 micrometers using a scraper, and then placed in a vacuum drying oven at 60 ℃ for 10 h to obtain zinc foil with modified coating. (4) Electrolyte preparation: Soluble zinc salt is dissolved in deionized water to prepare a salt solution with a concentration of 2-5 mol / L. -1 ; (5) The manganese-based compound positive electrode used in the button cell is prepared by the following method: manganese dioxide, conductive agent, and binder are mixed in a mass ratio of 8:1:1, and some solvent is added to prepare a slurry. The slurry is coated onto carbon cloth and dried in a vacuum drying oven at 60°C for 10 h to obtain a manganese dioxide positive electrode sheet. The mass loading of the manganese-based compound positive electrode material in the manganese dioxide positive electrode sheet is 1.0~10.0 mg cm⁻¹. -2 ; (6) The manganese-based compound positive electrode sheet used in the soft-pack battery is prepared by the following method: A certain amount of solvent is added and mixed into a dough-like consistency according to the mass ratio of manganese dioxide: conductive agent: binder = 8:1:

1. The dough is then rolled onto a Ti mesh and dried in a vacuum drying oven at 60 °C for 10 h to obtain the manganese dioxide positive electrode sheet. The mass loading of the manganese-based compound positive electrode material in the manganese dioxide positive electrode sheet is 30~110 mg cm⁻¹. -2 ; (7) Using the zinc foil prepared in step (3) as the negative electrode, the manganese dioxide positive electrode sheet prepared in step (5) as the positive electrode, and glass fiber as the separator, the electrolyte prepared in step (4) is added to assemble a button cell (CR2032 type), and its zinc storage performance is tested. (8) Using the zinc foil prepared in step (3) as the negative electrode, the manganese dioxide positive electrode sheet prepared in step (6) as the positive electrode, and glass fiber as the separator, the electrolyte prepared in step (4) is added dropwise to assemble a soft pack battery, and its zinc storage performance is tested.

2. The application according to claim 1, characterized in that, The anti-corrosion coating mentioned in step (2) is a functional epoxy resin coating produced by Fujian Wan'an Industrial Group.

3. The application according to claim 1, characterized in that, The volume range of the anti-corrosion coating used in step (2) is 99 mL-200 L.

4. The application according to claim 1, characterized in that, The volume ratio of the anti-corrosion coating described in step (2) to the solution prepared in step (1) is in the range of 49-100:

1.

5. The application according to claim 1, characterized in that, The soluble zinc salt mentioned in step (4) is selected from zinc sulfate, zinc trifluoromethanesulfonate, zinc acetate, zinc chloride or zinc perchlorate.

6. The application according to claim 1, characterized in that, The method for assembling a coin cell in step (7) is as follows: the zinc foil coated with the modified coating prepared in step (3) is used as the negative electrode, the manganese dioxide positive electrode sheet prepared in step (5) is used as the positive electrode, glass fiber is used as the separator, and the electrolyte prepared in step (4) is added to assemble a coin cell.

7. The application according to claim 1, characterized in that, The method for assembling a soft-pack battery in step (8) is as follows: the outer packaging aluminum-plastic film is 12 cm × 12 cm in size, the single piece size of the coating-modified zinc foil negative electrode prepared in step (3) is 10 cm × 10 cm, the single piece size of the manganese dioxide positive electrode obtained in step (6) is 9 cm × 9 cm, and the single piece size of the glass fiber separator is 11 cm × 11 cm. The zinc foil negative electrode, glass fiber separator, and manganese dioxide positive electrode are stacked in sequence, and the electrolyte obtained in step (4) is introduced to assemble a soft-pack battery.

Images