Mixed electrolyte containing amino group, imidazolyl group and sulfonic group and preparation method and application thereof

Abstract

The invention discloses a mixed electrolyte containing an amino group, an imidazolyl group and a sulfonic group, and a preparation method and application thereof. Wherein the mixed electrolyte comprises deionized water, zinc salt and an additive; the additive comprises a first compound containing an amino group and an imidazolyl group and a second compound containing a sulfonic group; in the mixed electrolyte, the concentration of zinc ions is 0.3 mol / L to 10 mol / L, and the total concentration of amino, imidazolyl and sulfo is 0.06 mol / L to 1.2 mol / L; the ratio of the total molar weight of the amino and the imidazolyl to the molar weight of the sulfonic acid group is (1-4): 1. According to the mixed electrolyte, a layer of compact and uniform gradient type solid electrolyte membrane rich in N and S can be deposited on the surface of the zinc negative electrode, so that side reactions such as corrosion, dendritic crystal growth and hydrogen evolution of the zinc negative electrode in the charging and discharging process are inhibited. The water-based zinc ion battery assembled by using the mixed electrolyte is relatively excellent in performance, and the cycle life of the water-based zinc ion battery can be remarkably prolonged.

Description

Technical Field

[0001] The invention relates to the field of aqueous zinc ion batteries, and in particular to a mixed electrolyte containing an amino group, an imidazole group and a sulfonic acid group, and a preparation method and application thereof. Background Art

[0002] As the most mainstream energy storage technology, commercial lithium-ion batteries are severely restricted in their development due to limited lithium resources, high prices, and unstable safety. Aqueous zinc-ion batteries have become a large-scale energy storage technology with great potential due to their abundant zinc resources, low cost, high safety, environmental friendliness, and high discharge specific capacity. However, in actual applications, the zinc negative electrode faces problems such as passivation, corrosion, dendrite growth, and hydrogen evolution reaction, which seriously restricts its commercialization process. At present, the cycle life of aqueous zinc-ion batteries is mainly optimized by means of interface modification, current collector design, three-dimensional structure construction, and diaphragm modification. However, the above methods all have the disadvantages of complex operation, high cost, and difficulty in large-scale production, and the performance of the modified aqueous zinc-ion batteries is still not ideal.

[0003] Therefore, the prior art still needs to be improved and developed. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a mixed electrolyte containing amino, imidazole and sulfonic acid groups, and a preparation method and application thereof, aiming to solve the problem of short cycle life of existing aqueous zinc ion batteries by improving the electrolyte of aqueous zinc ion batteries.

[0005] The technical solution of the present invention is as follows: In a first aspect, a mixed electrolyte containing an amino group, an imidazole group and a sulfonic acid group is provided, wherein the mixed electrolyte comprises: deionized water, a zinc salt and an additive; The additive comprises: a first compound containing an amino group and an imidazole group and a second compound containing a sulfonic acid group; In the mixed electrolyte, the concentration of zinc ions is 0.3-10 mol / L, the total concentration of amino, imidazole and sulfonic acid groups is 0.06-1.2 mol / L; and the ratio of the total molar amount of amino and imidazole groups to the molar amount of sulfonic acid groups is (1-4):1.

[0006] In a preferred technical solution, the zinc salt is selected from one or more of zinc sulfate, zinc trifluoromethanesulfonate, zinc chloride, zinc acetate, and zinc nitrate.

[0007] In a preferred technical solution, the first compound containing an amino group and an imidazole group is selected from one or more of 2-aminoimidazole sulfate, 2-aminoimidazole, 5-aminoimidazole-4-carboxamide, 2-nitroimidazole, 1,4-dimethyl-5-aminoimidazole hydrochloride, and 4-aminoimidazole-2-carboxylic acid ethyl ester.

[0008] In a preferred technical solution, the second compound containing a sulfonic acid group is selected from one or more of sodium allyl sulfonate, sodium propargyl sulfonate, sodium benzene sulfinate, sodium 1,5-naphthalene disulfonate, sodium xylene sulfonate, sodium hydroxymethane sulfonate, sodium vinyl sulfonate, sodium polydisulfide propane sulfonate, sodium butynol ether propane sulfonate, and sodium alkyl sulfonate.

[0009] According to a preferred technical solution, in the mixed electrolyte, the total concentration of amino groups and imidazole groups is 0.03-1 mol / L.

[0010] According to a preferred technical solution, in the mixed electrolyte, the concentration of sulfonic acid groups is 0.03-0.2 mol / L.

[0011] According to a preferred technical solution, the pH of the mixed electrolyte is 3.5-7.

[0012] In a second aspect, a method for preparing the mixed electrolyte as described in the first aspect is provided, the preparation method comprising: dissolving a zinc salt and an additive in deionized water to obtain a mixed electrolyte.

[0013] In a third aspect, a use of the mixed electrolyte as described in the first aspect is provided, wherein the mixed electrolyte is applied to an aqueous zinc ion battery.

[0014] In a fourth aspect, an aqueous zinc ion battery is provided, comprising the mixed electrolyte as described in the first aspect.

[0015] Beneficial effects: The present invention provides a mixed electrolyte containing amino, imidazole and sulfonic acid groups, and a preparation method and application thereof. Compared with the prior art, the mixed electrolyte of the present invention contains amino, imidazole and sulfonic acid groups. When used as an electrolyte for an aqueous zinc ion battery, the strong adsorption capacity between amino, sulfonic acid and zinc ions in the mixed electrolyte, as well as the reduction reaction of amino, sulfonic acid and imidazole groups during discharge can be utilized to deposit a dense and uniform gradient solid electrolyte film rich in N and S on the surface of the zinc negative electrode, thereby inhibiting corrosion, dendrite growth, and hydrogen evolution and other side reactions of the zinc negative electrode during the charge and discharge process; wherein, the amino and imidazole groups simultaneously contribute to the formation of Zn3N2, and should be on the same compound, otherwise it is not conducive to the electron-acquisition reaction of the N atom and will interfere with the N 2-The reduction of Zn3N2 is not uniform, and the assembled Zn / / Zn symmetric battery has poor performance, which is not as good as the system in which the amino group and the imidazole group are in the same compound. In addition, the sulfonic acid group and the zinc ion have a strong binding energy, which can accelerate the desolvation process of the zinc ion, thereby inducing its uniform deposition and stripping. In addition, the preparation method of the mixed electrolyte is simple, easy to operate, suitable for industrial production, and the cost of the additive is relatively cheap, which can meet the needs of industrial production and commercial application of aqueous zinc ion batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 The Zn / / Zn symmetric battery assembled with the mixed electrolyte of Example 3 was 2 The current density and 1 mAh / cm 2 Cycling performance curve under discharge depth conditions.

[0017] Figure 2 The Zn / / Zn symmetrical battery assembled with the mixed electrolyte of Example 4 was 2 The current density and 10 mAh / cm 2 Cycling performance curve under discharge depth conditions. DETAILED DESCRIPTION

[0018] The present invention provides a mixed electrolyte containing an amino group, an imidazole group and a sulfonic acid group, and a preparation method and application thereof. In order to make the purpose, technical scheme and effect of the present invention clearer and more specific, the present invention is further described in detail below.

[0019] The embodiment of the present invention provides a mixed electrolyte containing amino groups, imidazole groups and sulfonic acid groups, wherein the mixed electrolyte comprises: deionized water, zinc salt and additives; The additive comprises: a first compound containing an amino group and an imidazole group and a second compound containing a sulfonic acid group; In the mixed electrolyte, the concentration of zinc ions is 0.3-10 mol / L, the total concentration of amino, imidazole and sulfonic acid groups is 0.06-1.2 mol / L; and the ratio of the total molar amount of amino and imidazole groups to the molar amount of sulfonic acid groups is (1-4):1.

[0020] Specifically, the mixed electrolyte of the present invention contains amino, imidazole and sulfonic acid groups. When used as the electrolyte of an aqueous zinc ion battery, the strong adsorption capacity between the amino, sulfonic acid and zinc ions in the mixed electrolyte and the reduction reaction of the amino, sulfonic acid and imidazole groups during the discharge process (SO3 - + e - + Zn 2+ = ZnSO3, 2N 2-+2e - +3Zn 2+ = Zn3N2), thereby depositing a dense and uniform gradient solid electrolyte film rich in N and S on the surface of the zinc negative electrode, thereby inhibiting the corrosion, dendrite growth, and hydrogen evolution of the zinc negative electrode during the charge and discharge process; among them, the amino group and the imidazole group contribute to the formation of Zn3N2 at the same time, and should be on the same compound, otherwise it is not conducive to the electron-accepting reaction of the N atom and will interfere with the N 2- The reduction of Zn3N2 is not uniform, and the assembled Zn / / Zn symmetric battery has poor performance, which is not as good as the system in which amino and imidazole groups are in the same compound. In addition, the strong binding energy between sulfonic acid group and zinc ion can accelerate the desolvation process of zinc ion, thereby inducing its uniform deposition and stripping.

[0021] In one embodiment, the zinc salt is selected from one or more of zinc sulfate, zinc trifluoromethanesulfonate, zinc chloride, zinc acetate, and zinc nitrate.

[0022] In one embodiment, the first compound containing an amino group and an imidazole group is selected from one or more of 2-aminoimidazole sulfate, 2-aminoimidazole, 5-aminoimidazole-4-carboxamide, 2-nitroimidazole, 1,4-dimethyl-5-aminoimidazole hydrochloride, and 4-aminoimidazole-2-carboxylic acid ethyl ester.

[0023] In one embodiment, the second compound containing a sulfonic acid group is selected from one or more of sodium allyl sulfonate, sodium propargyl sulfonate, sodium benzene sulfinate, sodium 1,5-naphthalene disulfonate, sodium xylene sulfonate, sodium hydroxymethane sulfonate, sodium vinyl sulfonate, sodium polydisulfide propane sulfonate, sodium butynol ether propane sulfonate, and sodium alkyl sulfonate.

[0024] In one embodiment, the total concentration of amino and imidazole groups in the mixed electrolyte is 0.03-1 mol / L. Within the total concentration range of amino and imidazole groups in the mixed electrolyte, the strong adsorption capacity between amino and zinc ions and the reduction of amino and imidazole groups during discharge can be utilized to deposit a N-rich, dense and uniform gradient solid electrolyte film on the surface of the zinc negative electrode, which can not only hinder the corrosion of zinc, but also promote the uniform deposition of zinc ions.

[0025] In one embodiment, the concentration of sulfonic acid groups in the mixed electrolyte is 0.03-0.2 mol / L. Within this concentration range, the sulfonic acid groups in the mixed electrolyte can provide S atoms in the gradient solid electrolyte membrane, and the sulfonic acid groups have strong binding energy with zinc ions, which can accelerate the desolvation process and promote the uniform deposition and stripping of zinc ions.

[0026] In one embodiment, the pH of the mixed electrolyte is 3.5-7.

[0027] An embodiment of the present invention provides a method for preparing the mixed electrolyte as described above, the preparation method comprising: dissolving a zinc salt and an additive in deionized water to obtain the mixed electrolyte.

[0028] An embodiment of the present invention provides an application of the mixed electrolyte as described above, wherein the mixed electrolyte is applied to an aqueous zinc ion battery.

[0029] An embodiment of the present invention provides an aqueous zinc ion battery, comprising the mixed electrolyte as described above.

[0030] In one embodiment, the aqueous zinc ion battery comprises: a zinc electrode, a glass fiber separator, and the mixed electrolyte containing amino groups, imidazole groups, and sulfonic acid groups as described above.

[0031] The present invention will be further described below by means of specific examples.

[0032] Example 1 At room temperature, 0.09 mmol of 2-aminoimidazole and 0.06 mmol of sodium 1,5-naphthalene disulfonate were added to 1 mL of 1 mol / L zinc sulfate solution, and the mixture was evenly mixed to obtain a mixed electrolyte containing amino groups, imidazole groups and sulfonic acid groups.

[0033] Example 2 At room temperature, 0.015 mmol of 2-aminoimidazole sulfate (containing 0.03 mmol of amino group and 0.03 mmol of imidazole group) and 0.03 mmol of sodium propargyl sulfonate were added to 1 mL of 1 mol / L zinc acetate solution, and after mixing evenly, a mixed electrolyte containing amino group, imidazole group and sulfonic acid group was obtained.

[0034] Example 3 At room temperature, 0.05 mmol of 2-aminoimidazole sulfate (containing 0.1 mmol of amino group and 0.1 mmol of imidazole group) and 0.05 mmol of sodium propargyl sulfonate were added to 1 mL of 1 mol / L zinc sulfate solution and mixed evenly to obtain a mixed electrolyte containing amino group, imidazole group and sulfonic acid group.

[0035] Example 4 At room temperature, 0.05 mmol of 2-aminoimidazole sulfate (containing 0.1 mmol of amino group and 0.1 mmol of imidazole group) and 0.05 mmol of sodium allyl sulfonate were added to 1 mL of 2 mol / L zinc sulfate sulfonate solution, and after mixing evenly, a mixed electrolyte containing amino group, imidazole group and sulfonic acid group was obtained.

[0036] Example 5 At room temperature, 0.1 mmol of 2-aminoimidazole and 0.1 mmol of sodium allyl sulfonate were added to 1 mL of 1 mol / L zinc sulfate solution, and the mixture was evenly mixed to obtain a mixed electrolyte containing amino groups, imidazole groups and sulfonic acid groups.

[0037] Example 6 At room temperature, 0.1 mmol of 2-aminoimidazole and 0.05 mmol of sodium 1,5-naphthalene disulfonate were added to 1 mL of 1 mol / L zinc trifluoromethanesulfonate solution, and the mixture was evenly mixed to obtain a mixed electrolyte containing amino groups, imidazole groups and sulfonic acid groups.

[0038] Example 7 At room temperature, 0.1 mmol of 1,4-dimethyl-5-aminoimidazole hydrochloride and 0.08 mmol of sodium allyl sulfonate were added to 1 mL of 1 mol / L zinc nitrate solution, and the mixture was evenly mixed to obtain a mixed electrolyte containing amino, imidazole and sulfonic acid groups.

[0039] Comparative Example 1 At room temperature, 0.09 mmol of 2-aminoimidazole was added to 1 mL of 1 mol / L zinc sulfate solution and mixed evenly to obtain an amino-containing mixed electrolyte.

[0040] Comparative Example 2 At room temperature, 0.06 mmol of sodium 1,5-naphthalene disulfonate was added to 1 mL of 1 mol / L zinc sulfate solution and mixed evenly to obtain a mixed electrolyte containing sulfonic acid groups.

[0041] Comparative Example 3 At room temperature, 0.09 mmol of N-methylimidazole and 0.06 mmol of sodium 1,5-naphthalene disulfonate were added to 1 mL of 1 mol / L zinc sulfate solution, and the mixture was evenly mixed to obtain a mixed electrolyte containing imidazole groups and sulfonic acid groups.

[0042] Performance Testing The mixed electrolytes of Examples 1 to 7 and Comparative Examples 1 to 3 were used as electrolytes for aqueous zinc ion batteries, and the polished zinc sheets were used as positive and negative electrodes, with an effective area of ​​about 1.539 cm 2 , glass fiber membrane as a separator, CR2032 button-type zinc ion battery was assembled; the electrochemical performance of the assembled Zn / / Zn symmetrical battery was tested under different conditions using an electrochemical workstation, and the test results are shown in Table 1 below.

[0043] Table 1 Electrochemical performance test results of zinc ion battery

[0044] In Table 1, test ① is: at 1 mA / cm2 The current density and 1 mAh / cm 2 The cycle was carried out under the condition of discharge depth of 5mA / cm 2 The current density and 5 mAh / cm 2 The cycle was carried out under the condition of the discharge depth of 10mA / cm 2 The current density and 10 mAh / cm 2 The cycle was carried out under the condition of the discharge depth of 20 mA / cm 2 The current density is 20 mAh / cm 2 The cycle was carried out under the condition of the discharge depth of 40mA / cm 2 The current density is 40 mAh / cm 2 Cycling under depth of discharge conditions.

[0045] In addition, the Zn / / Zn symmetric battery assembled using the mixed electrolyte of Example 3 has a high conductivity at 1 mA / cm 2 The current density and 1 mAh / cm 2 The cycle is carried out under the condition of discharge depth, and the cycle performance curve is shown in the figure Figure 1 As shown in Figure 2, the cycle time is as long as 2600 hours. The Zn / / Zn symmetric battery assembled using the mixed electrolyte of Example 4 is 2 The current density and 10 mAh / cm 2 The cycle is carried out under the condition of discharge depth, and the cycle performance curve is shown in the figure Figure 2 As shown, the cycle time is up to 428 hours.

[0046] In summary, the present invention provides a mixed electrolyte containing amino groups, imidazole groups and sulfonic acid groups, and a preparation method and application thereof. The mixed electrolyte comprises: deionized water, zinc salt and additives; the additives comprise: a first compound containing amino groups and imidazole groups and a second compound containing sulfonic acid groups; in the mixed electrolyte, the concentration of zinc ions is 0.3-10 mol / L, and the total concentration of amino groups, imidazole groups and sulfonic acid groups is 0.06-1.2 mol / L; the ratio of the sum of the molar amounts of amino groups and imidazole groups to the molar amount of sulfonic acid groups is (1-4):1. The mixed electrolyte of the present invention contains amino groups, imidazole groups and sulfonic acid groups. When used as an electrolyte for an aqueous zinc ion battery, the strong adsorption capacity between amino groups, sulfonic acid groups and zinc ions in the mixed electrolyte, as well as the reduction reaction of amino groups, sulfonic acid groups and imidazole groups during discharge (SO3 - + e - +Zn 2+ = ZnSO3, 2N 2- +2e - + 3Zn2+ = Zn3N2), thereby depositing a dense and uniform gradient solid electrolyte film rich in N and S on the surface of the zinc negative electrode, thereby inhibiting the corrosion, dendrite growth, and hydrogen evolution of the zinc negative electrode during the charge and discharge process; among them, the amino group and the imidazole group contribute to the formation of Zn3N2 at the same time, and should be on the same compound, otherwise it is not conducive to the electron-accepting reaction of the N atom and will interfere with the N 2- The reduction of Zn3N2 is not uniform, and the assembled Zn / / Zn symmetric battery has poor performance, which is not as good as the system in which amino and imidazole groups are in the same compound. In addition, the strong binding energy between sulfonic acid group and zinc ion can accelerate the desolvation process of zinc ion, thereby inducing its uniform deposition and stripping.

[0047] The preparation method of the mixed electrolyte is simple, easy to operate, suitable for industrial production, and the cost of additives is relatively cheap, which can meet the needs of industrial production and commercial application of aqueous zinc ion batteries. In addition, the performance of aqueous zinc ion batteries assembled with the mixed electrolyte is also relatively excellent, and the cycle life of aqueous zinc batteries can be significantly improved by using a trace amount of additives, and the cost of additives is also lower than that of most additives.

[0048] It should be understood that the application of the present invention is not limited to the above examples. For ordinary technicians in this field, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A mixed electrolyte containing amino, imidazole and sulfonic acid groups, characterized in that: The mixed electrolyte comprises: deionized water, zinc salt and additives; The additive comprises: a first compound containing an amino group and an imidazole group and a second compound containing a sulfonic acid group; In the mixed electrolyte, the concentration of zinc ions is 0.3-10 mol / L, the total concentration of amino, imidazole and sulfonic acid groups is 0.06-1.2 mol / L; and the ratio of the total molar amount of amino and imidazole groups to the molar amount of sulfonic acid groups is (1-4):

1.

2. The mixed electrolyte according to claim 1, characterized in that: The zinc salt is selected from one or more of zinc sulfate, zinc trifluoromethanesulfonate, zinc chloride, zinc acetate, and zinc nitrate.

3. The mixed electrolyte according to claim 1, characterized in that: The first compound containing amino and imidazole groups is selected from one or more of 2-aminoimidazole sulfate, 2-aminoimidazole, 5-aminoimidazole-4-carboxamide, 2-nitroimidazole, 1,4-dimethyl-5-aminoimidazole hydrochloride, and 4-aminoimidazole-2-carboxylic acid ethyl ester.

4. The mixed electrolyte according to claim 1, characterized in that: The second compound containing a sulfonic acid group is selected from one or more of sodium allyl sulfonate, sodium propargyl sulfonate, sodium benzene sulfinate, sodium 1,5-naphthalene disulfonate, sodium xylene sulfonate, sodium hydroxymethane sulfonate, sodium vinyl sulfonate, sodium polydisulfide propane sulfonate, sodium butynol ether propane sulfonate, and sodium alkyl sulfonate.

5. The mixed electrolyte according to claim 1, characterized in that: In the mixed electrolyte, the total concentration of amino groups and imidazole groups is 0.03-1 mol / L.

6. The mixed electrolyte according to claim 1, characterized in that: In the mixed electrolyte, the concentration of sulfonic acid groups is 0.03-0.2 mol / L.

7. The mixed electrolyte according to claim 1, characterized in that: The pH of the mixed electrolyte is 3.5-7.

8. A method for preparing a mixed electrolyte according to any one of claims 1 to 7, characterized in that: The preparation method comprises: dissolving zinc salt and additives in deionized water to obtain a mixed electrolyte.

9. A use of the mixed electrolyte according to any one of claims 1 to 7, characterized in that: The mixed electrolyte is applied to aqueous zinc ion batteries.

10. An aqueous zinc ion battery, characterized in that: Comprising the mixed electrolyte as described in any one of claims 1 to 7.

Images