A multiphase wet sand electrolyte, a preparation method and application thereof in high-temperature aqueous zinc ion battery

Abstract

The application relates to the technical field of water-based electrolyte preparation, and discloses a multiphase wet sand electrolyte, a preparation method and application of the multiphase wet sand electrolyte in a high-temperature water-based zinc ion battery, which comprises the following steps: dissolving a zinc salt into a mixture of water and an organic cosolvent, then adding inorganic nanoparticles, and performing wall breaking and ultrasonic dispersion until complete dispersion and uniformity are achieved, so as to obtain a water-based zinc ion battery multiphase wet sand electrolyte. The addition of the organic cosolvent and the inorganic nanoparticles can effectively destroy the hydrogen bond network of free water, greatly reduce the activity of water, improve the thermal stability of the wet sand electrolyte, and meanwhile, the inorganic nanoparticles can form a dynamic interface layer on the surface of a zinc negative electrode, reduce an interface side reaction, and greatly improve the cycle life of the water-based zinc ion battery under high temperature.

Description

Technical Field

[0001] This invention relates to the field of electrolyte preparation technology, and in particular to a multiphase wet sand electrolyte containing organic solvent, water and inorganic nanoparticles and its application in high-temperature aqueous zinc-ion batteries. Background Technology

[0002] With increasing energy demand and growing emphasis on environmental protection, lithium-ion batteries are widely used in portable electronic devices and electric vehicles due to their high energy density and long cycle life. However, the limited availability and high cost of lithium resources restrict their large-scale application. Therefore, developing a cost-effective, environmentally friendly, and sustainable alternative battery system is of great significance. Zinc-ion batteries, as a promising alternative energy storage system, have significant advantages over lithium-ion batteries, including abundant reserves, low cost, safe and non-flammable electrolyte, a wider operating temperature range, and good resistance to overcharge and over-discharge. To meet the special application requirements under high-temperature conditions, such as oil drilling, geothermal power generation, and aerospace, it is necessary to improve battery performance at high temperatures, increase safety, extend battery life, and enhance environmental adaptability to ensure normal operation of equipment under extreme climatic conditions. However, at high temperatures, the zinc anode side faces severe side reactions (including hydrogen evolution reaction (HER) and zinc corrosion) and accelerates the growth of zinc dendrites, leading to rapid battery failure. Currently, modification strategies include using polymer electrolytes and co-solvent electrolytes to suppress these adverse reactions and to stabilize the aqueous solution during cycling at relatively high temperatures. However, to meet the requirements of applications under more demanding conditions, it is necessary to explore the possibility of aqueous zinc-ion batteries cycling at higher temperatures, even reaching the boiling point of water. Therefore, in recent years, the research and development of various novel electrolyte preparation processes for zinc-ion batteries has received widespread attention. Summary of the Invention

[0003] Improving the high-temperature cycle performance of zinc-ion batteries using multiphase wet sand electrolytes mainly involves utilizing organic solvents and inorganic nanoparticles to disrupt the hydrogen bond network of water, inhibit the activity of free water, and improve the thermal stability of the electrolyte. The addition of inorganic nanoparticles forms a dynamic interface layer, and the synergistic effect of both significantly reduces water activity and side reactions. In this process, the type and content of organic solvents and inorganic nanoparticles are crucial to the final cycle performance. Therefore, this application discloses a multiphase wet sand electrolyte, its preparation method, and its application in high-temperature aqueous zinc-ion batteries: using ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), propylene glycol (PG), butanediol (BDO), n-butanol, 1-octanol, pentanol, 1-hexanol, isopropanol (IPA), isoamyl alcohol, and 2-butanol (2-butyl alcohol). One or more organic solvents selected from alcohol, 1,2-propanediol (PG), 1,3-butanediol, dimethyl sulfoxide (DMSO), trimethyl phosphate (TMP), triethyl phosphate (TEP), N,N-dimethylformamide (DMF), hexamethylphosphoramide (HMPA), and pyridine (Py) can be used as co-solvents. Organic co-solvents with high boiling points and strong hydrogen bonds can effectively disrupt the hydrogen bond network of water, reduce water activity, increase the boiling point of the electrolyte, and improve the solvation structure of zinc-ion battery electrolytes. The inorganic nanoparticles forming the wet sand electrolyte include one or more of the following: aluminum oxide (Al₂O₃), magnesium oxide (MgO), zinc oxide (ZnO), iron oxide (Fe₃O₄), titanium dioxide (TiO₂), silicon dioxide (SiO₂), strontium titanate (SrTiO₃), copper oxide (CuO), calcium oxide (CaO), silicon carbide (SiC), silicon nitride (Si₃N₄), boron nitride (BN), hydrotalcite, montmorillonite, carbon nitride (C₃N₄), and zirconium phosphate (ZrP). The large inorganic nanoparticles suspended in the electrolyte can promote uniform zinc deposition, inhibit zinc dendrite growth, and reduce the formation of byproducts at high temperatures through a spatially ordered network structure formed by van der Waals forces or intermolecular hydrogen bonds. This novel wet sand electrolyte has broad application prospects in the zinc-ion battery electrolyte industry.

[0004] The objective of this invention is achieved through the following technical solution:

[0005] A method for preparing a multiphase wet sand electrolyte includes: dissolving zinc salt in a mixture of water and an organic co-solvent, then adding inorganic nanoparticles, and ultrasonically breaking the cell walls until the particles are completely and uniformly dispersed to obtain an aqueous zinc ion multiphase wet sand electrolyte.

[0006] Further, the organic co-solvent is at least one of the following compounds: ethanol (Ethanol), ethylene glycol (EG), diethylene glycol (DEG), triethylene glycol (TEG), propylene glycol (PG), propanol (Propanol), butanediol (BDO), glycerol (Glycerol), n-butanol (n-Butanol), octanol (1-Octanol), pentanol (Pentanol), hexanol (1-Hexanol), heptanol (1-Heptanol), isopropanol (IPA), isoamyl alcohol (Isoamyl) The organic co-solvents include alcohol, 2-butanol, 1,2-propanediol (PG), 1,3-propanediol (1,3-PDO), 1,3-butanediol, cyclohexanol, dimethyl sulfoxide (DMSO), trimethyl phosphate (TMP), triethyl phosphate (TEP), N,N-dimethylformamide (DMF), hexamethylphosphoramide (HMPA), pyridine (Py), acetone, tetrahydrofuran (THF), 1,4-dioxane, n-butyl sulfone, dimethylacetamide (DMA), ethylamine, diethylamine, bis(2-methoxyethyl)ether, acetic acid (Ac), triethanolamine, and dimethyl ether (DME). Preferably, the molar ratio of the organic co-solvent to water is 0.1–10.

[0007] Further, the zinc salts include zinc trifluoromethanesulfonate (Zn(OTf)2), zinc sulfate (ZnSO4), zinc perchlorate (Zn(ClO4)2), zinc chloride (ZnCl2), zinc tetrafluoroborate (ZnBF4), zinc nitrate (Zn(NO3)2), zinc acetate ((CH3COO)2Zn), and zinc citrate (C 12 H 14 O 16 Zinc (Zn3), zinc methanesulfonate, zinc bromide (ZnBr2), zinc lactate (C6HO6Zn), zinc docosanoate, zinc undecenoate (CHO4Zn), zinc bromate (Zn(BrO3)2), zinc citrate (C 12 H 14 O 16 Zn3), zinc diethyldithiocarbamate (DBZ), zinc salicylate (C) 14 H 10 O6Zn), zinc stearate (C 36 H 70 O4Zn), zinc p-toluenesulfonate (C 14 H14 O6S2Zn), zinc benzenesulfinate (C 12 H 14 The zinc salt is selected from one or more of the following: zinc O6S2Zn, zinc trifluoroacetate (C2F3O2Zn), zinc aminosulfonate (H3NO3SZn), zinc formate (C2H2O4Zn), and zinc oxalate (ZnC2O4.2H2O). Preferably, the concentration of the zinc salt in the electrolyte is 0.5M-5M.

[0008] Further, the inorganic nanoparticles are one or a mixture of two or more of the following: aluminum oxide (Al₂O₃), magnesium oxide (MgO), zinc oxide (ZnO), iron oxide (Fe₃O₄), titanium dioxide (TiO₂), silicon dioxide (SiO₂), strontium titanate (SrTiO₃), copper oxide (CuO), calcium oxide (CaO), silicon carbide (SiC), silicon nitride (Si₃N₄), boron nitride (BN), hydrotalcite, montmorillonite, carbon nitride (C₃N₄), and zirconium phosphate (ZrP). Preferably, the inorganic nanoparticles account for 1-50% of the total mass of the electrolyte.

[0009] Furthermore, the size range of the inorganic nanoparticles is 5-100 nanometers.

[0010] The above-described method for preparing electrolyte for zinc-ion batteries uses commercially available raw materials, and the equipment and processes employed are well-known to those skilled in the art. It can be successfully applied in high-temperature aqueous zinc-ion batteries.

[0011] The advantages and positive effects of this invention are:

[0012] 1. The method of the present invention is low in cost, simple to operate, and the drug ingredients are safe.

[0013] 2. This invention introduces alcohol-based organic solvents as co-solvents into zinc-ion batteries, which can reshape the hydrogen bond network, reduce water activity, and adjust the solvation structure. The addition of oxide particles to the electrolyte can adjust the SEI composition. The synergistic effect of the two can reduce water activity, reduce the generation of by-products, and improve gas production, enabling zinc-ion batteries to have a longer lifespan and better performance. Attached Figure Description

[0014] Figure 1 The time-voltage curves of the symmetrical cells at high temperature for Example 1 and the control sample are shown.

[0015] Figure 2 The charge-discharge curves of the full battery at high temperature for Example 1 and the control sample are shown.

[0016] Figure 3 The time-voltage curves of the symmetrical cells at high temperature for Example 2 and the control sample are shown.

[0017] Figure 4 The charge-discharge curves of the full battery at high temperature are for Example 2 and the control sample. Detailed Implementation

[0018] The following detailed description, in conjunction with specific embodiments, provides further insight into the invention. It should be understood that these embodiments are illustrative and not intended to limit the scope of the invention. The implementation conditions used in the embodiments may be further adjusted based on specific construction conditions; implementation conditions not explicitly stated are typically those used in routine experiments.

[0019] Example 1

[0020] A method for preparing a zinc-ion battery electrolyte includes: dissolving 3.05 mg Zn(OTf)₂ in a mixed solution of 4 mL EG and 0.2 mL H₂O, and sonicating until the Zn(OTf)₂ is completely dissolved. Then, adding 30% TiO₂ (size range approximately 20 nm) by mass of the total electrolyte, and using a cell wall disruptor to break down the TiO₂ until it is completely dispersed in the electrolyte to obtain a wet sand electrolyte for zinc-ion batteries.

[0021] Comparative sample preparation method: Dissolve 1.45 mg Zn(OTf)2 in 2 mL H2O and sonicate until Zn(OTf)2 is completely dissolved to obtain zinc ion battery electrolyte.

[0022] A zinc-zinc symmetric battery was assembled using the prepared zinc-ion battery multiphase wet sand electrolyte. Its time-voltage curve under high-temperature long-cycle testing is shown below. Figure 1 As shown, at 80℃, the current density is 1 mA / cm². 2 The capacity is 0.5mAh / cm³. 2 The electrolyte can maintain a stable cycle of 1115 hours and a polarization voltage of 0.15V, which indicates its stability at high temperatures. This suggests that interfacial issues and water activity are significantly suppressed, resulting in an improved cycle life.

[0023] Method for preparing positive electrode material: Mix polyaniline, conductive carbon, and PVDF in a mass ratio of 8:1:1 to form a slurry, coat it onto carbon cloth, and dry it in a vacuum drying oven at 80°C for 12 hours to obtain the positive electrode sheet.

[0024] Full cell assembly method: Use 10mm diameter polyaniline as positive electrode, 12mm diameter zinc sheet as negative electrode, glass fiber GF-F as separator, drop the above wet sand electrolyte, and encapsulate under 1.0T pressure.

[0025] The full-cell zinc-ion battery obtained was tested at high temperature, and the full-cell cycle stability test curve is shown in the figure below. Figure 2As shown, at 80℃ and a current density of 1A / g, the capacity retention rate can reach 70% after 1736 cycles. At the same time, it exhibits a high discharge specific capacity of 127mAh / g at high temperature, which indicates that the electrolyte still maintains good high-temperature cycling stability in the full cell. It can be inferred that the solvation structure has been optimized, side reactions have been significantly suppressed, and cycle life has been improved.

[0026] Example 2

[0027] A method for preparing a zinc-ion battery electrolyte includes: dissolving 1.59 mg of Zn(OTf)₂ in a mixed solution of 2 mL DEG and 0.188 mL H₂O, and sonicating until the Zn(OTf)₂ is completely dissolved. Then, adding 10% Al₂O₃ (size range approximately 20 nm) by mass of the total electrolyte, and using a cell wall disruptor to break down the Al₂O₃ until it is completely dispersed in the electrolyte to obtain a multiphase wet sand electrolyte for zinc-ion batteries.

[0028] Comparative sample preparation method: Dissolve 1.59 mg Zn(OTf)2 in a mixed solution of 2 mL DEG and 0.188 mL H2O, and sonicate until Zn(OTf)2 is completely dissolved to obtain zinc ion battery electrolyte.

[0029] A zinc-zinc symmetric battery was assembled using the prepared zinc-ion battery multiphase wet sand electrolyte. Its time-voltage curves at different current densities and high temperatures are shown below. Figure 3 As shown, at 80°C, the current density ranges from 0.5 to 8 mA / cm². 2 The fact that the electrolyte can maintain a minimum polarization voltage at high temperatures and high currents indicates that it can maintain stable cycling properties. This suggests that interface problems and water activity are significantly suppressed, resulting in improved cycle life.

[0030] Method for preparing positive electrode material: Mix polyaniline, conductive carbon, and PVDF in a mass ratio of 8:1:1 to form a slurry, coat it onto carbon cloth, and dry it in a vacuum drying oven at 80°C for 12 hours to obtain the positive electrode sheet.

[0031] Full cell assembly method: Use 10mm diameter polyaniline as positive electrode, 12mm diameter zinc sheet as negative electrode, glass fiber GF-F as separator, drop the above wet sand electrolyte, and encapsulate under 1.0T pressure.

[0032] The full-cell zinc-ion battery obtained was tested at high temperature, and the full-cell cycle stability test curve is shown in the figure below. Figure 4As shown, at 80℃ and a current density of 1A / g, the capacity retention rate can reach 48% after 1700 cycles. At the same time, it exhibits a high discharge specific capacity of 120mAh / g at high temperatures, which indicates that the electrolyte still maintains good high-temperature cycling stability in the full battery. It can be inferred that the solvation structure has been optimized, side reactions have been significantly suppressed, and cycle life has been improved.

[0033] The foregoing description provides a further detailed explanation of the invention in conjunction with specific embodiments, and it should not be construed that the specific implementation of the invention is limited to these descriptions. For those skilled in the art, any obvious simple deductions or substitutions without departing from the concept of the invention are within the scope of protection of the invention.

Claims

1. A method for preparing a multiphase wet sand electrolyte for a high-temperature aqueous zinc-ion battery, characterized in that, The preparation method is as follows: zinc salt is dissolved in a mixture of water and organic co-solvent, then inorganic nanoparticles are added, and the mixture is ultrasonically broken until it is completely and uniformly dispersed to obtain an aqueous zinc ion multiphase wet sand electrolyte; the size range of the inorganic nanoparticles is 5-100 nanometers. The organic cosolvent is at least one of the following compounds: ethanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, propanol, butanediol, glycerol, n-butanol, octanol, pentanol, hexanol, heptanol, isopropanol, isoamyl alcohol, 2-butanol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, cyclohexanol, dimethyl sulfoxide, trimethyl phosphate, triethyl phosphate, N,N-dimethylformamide, hexamethylphosphoramide, pyridine, acetone, tetrahydrofuran, dioxane, sulfone, dimethylacetamide, ethylamine, diethylamine, diethanolamine, acetic acid, triethanolamine, dimethyl ether; the molar ratio of the organic cosolvent to water is 0.1 to 10; The inorganic nanoparticles account for 1 to 50% of the total mass of the electrolyte.

2. The method for preparing a multiphase wet sand electrolyte for a high-temperature aqueous zinc-ion battery according to claim 1, characterized in that, The zinc salt is one or a mixture of two or more of the following: zinc trifluoromethanesulfonate, zinc sulfate, zinc perchlorate, zinc chloride, zinc tetrafluoroborate, zinc nitrate, zinc acetate, zinc citrate, zinc methanesulfonate, zinc bromide, zinc lactate, zinc docosanoate, zinc undecenoate, zinc bromate, zinc citrate, zinc diethyldithiocarbamate, zinc salicylate, zinc stearate, zinc p-toluenesulfonate, zinc benzenesulfinate, zinc trifluoroacetate, zinc ammoniasulfonate, zinc formate, and zinc oxalate.

3. The method for preparing a multiphase wet sand electrolyte for a high-temperature aqueous zinc-ion battery according to claim 1, characterized in that, The concentration of the zinc salt in the electrolyte is 0.5 M-5 M.

4. The method for preparing a multiphase wet sand electrolyte for a high-temperature aqueous zinc-ion battery according to claim 1, characterized in that, The inorganic nanoparticles are one or a mixture of two or more of the following: aluminum oxide, magnesium oxide, zinc oxide, iron oxide, titanium dioxide, silicon dioxide, strontium titanate, copper oxide, calcium oxide, silicon carbide, silicon nitride, boron nitride, hydrotalcite, montmorillonite, carbon nitride, and zirconium phosphate.

5. A multiphase wet sand electrolyte prepared by the preparation method of a high-temperature aqueous zinc-ion battery according to any one of claims 1-4.

6. The application of a multiphase wet sand electrolyte prepared by the method for preparing a multiphase wet sand electrolyte for a high-temperature aqueous zinc-ion battery according to any one of claims 1-4, characterized in that, It is used in high-temperature aqueous zinc-ion batteries.

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