A mixed electrolyte containing amino, imidazole and sulfonic acid groups, and a preparation method and application thereof

Abstract

The application discloses 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, a zinc salt and an additive. The additive comprises 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, the total concentration of the amino groups, the imidazole groups and the sulfonic acid groups is 0.06-1.2 mol / L, and the ratio of the sum of the molar amounts of the amino groups and the imidazole groups to the molar amount of the sulfonic acid groups is (1-4):1. The mixed electrolyte can deposit a dense and uniform gradient solid electrolyte film rich in N and S on the surface of a zinc negative electrode, thereby inhibiting corrosion, dendrite growth and hydrogen evolution and other side reactions of the zinc negative electrode during charging and discharging. The water-based zinc ion battery assembled by using the mixed electrolyte has excellent performance and can significantly improve the cycle life of the water-based zinc battery.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aqueous zinc ion batteries, in particular to a mixed electrolyte containing amino, imidazole and sulfonic acid groups and a preparation method and application thereof. BACKGROUND

[0002] Commercial lithium ion batteries, as the most mainstream energy storage technology at present, are seriously limited in development due to limited lithium resources, high price and unstable safety. Aqueous zinc ion batteries have become a promising large-scale energy storage technology due to the advantages of abundant zinc resources, low cost, high safety, environmental friendliness and high discharge specific capacity. However, in practical applications, the zinc negative electrode faces problems such as passivation, corrosion, dendrite growth and hydrogen evolution reaction, which seriously limits 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 separator modification. However, the above methods 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

[0004] In view of the above shortcomings of the prior art, the purpose of the present application is to provide a mixed electrolyte containing amino, imidazole and sulfonic acid groups and a preparation method and application thereof, which aims to improve the electrolyte of aqueous zinc ion batteries, thereby solving the problem of short cycle life of existing aqueous zinc ion batteries in application.

[0005] The technical scheme of the present application is as follows:

[0006] In a first aspect, a mixed electrolyte containing amino, imidazole and sulfonic acid groups is provided, which comprises: deionized water, a zinc salt and an additive.

[0007] The additive comprises a first compound containing amino and imidazole groups and a second compound containing sulfonic acid groups.

[0008] 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 sum of the molar amounts of amino and imidazole groups to the molar amount of sulfonic acid groups is (1-4):1.

[0009] In a preferred technical scheme, the zinc salt is selected from one or more of zinc sulfate, zinc trifluoromethane sulfonate, zinc chloride, zinc acetate and zinc nitrate.

[0010] Preferably, 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-nitroimidazolidine, 1,4-dimethyl-5-aminoimidazole hydrochloride, and 4-aminoimidazole-2-carboxylic acid ethyl ester.

[0011] Preferably, the second compound containing sulfonic acid groups is selected from one or more of allyl sulfonic acid sodium, propargyl sulfonic acid sodium, benzenesulfonic acid sodium, 1,5-naphthalene disulfonic acid sodium, xylene sulfonic acid sodium, hydroxymethyl sulfonic acid sodium, vinyl sulfonic acid sodium, polydithiodipropyl sulfonic acid sodium, butynol ether propane sulfonic acid sodium, and alkanol sulfonic acid sodium.

[0012] Preferably, the total concentration of amino and imidazole groups in the mixed electrolyte is 0.03-1 mol / L.

[0013] Preferably, the concentration of sulfonic acid groups in the mixed electrolyte is 0.03-0.2 mol / L.

[0014] Preferably, the pH of the mixed electrolyte is 3.5-7.

[0015] In a second aspect, a preparation method of the mixed electrolyte according to the first aspect is provided, and the preparation method comprises: dissolving a zinc salt and an additive in deionized water to obtain the mixed electrolyte.

[0016] In a third aspect, an application of the mixed electrolyte according to the first aspect is provided, and the mixed electrolyte is applied to a water-based zinc ion battery.

[0017] In a fourth aspect, a water-based zinc ion battery is provided, and the water-based zinc ion battery comprises the mixed electrolyte according to the first aspect.

[0018] Beneficial effects: The application provides a mixed electrolyte containing amino, imidazole groups and sulfonic acid groups, and a preparation method and application thereof. Compared with the prior art, the mixed electrolyte of the application contains amino, imidazole groups and sulfonic acid groups, and when used as an electrolyte of a water-based zinc ion battery, the strong adsorption capacity between the amino, sulfonic acid groups and zinc ions in the mixed electrolyte, and the reduction reaction of the amino, sulfonic acid groups and imidazole groups in the discharge process can be utilized, so that a dense and uniform gradient-type solid electrolyte film rich in N and S is deposited on the surface of the zinc negative electrode, thereby inhibiting the corrosion, dendrite growth and hydrogen evolution and other side reactions of the zinc negative electrode in the charge and discharge process; the amino and imidazole groups contribute to the formation of Zn3N2 at the same time, and should be on the same compound, otherwise the electron transfer of N atoms will be interfered, which will interfere with the formation of Zn3N2 2-The reduction of the sulfonic acid group and the reduction of the amino group and the imidazole group, and the formed Zn3N2 is not uniform, the performance of the assembled Zn / / Zn symmetric battery is poor, and the system in which the amino group and the imidazole group are in the same compound is not as good as the system. In addition, the sulfonic acid group and the zinc ion have strong binding energy, which can accelerate the desolvation process of the zinc ion, thereby inducing 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 low, which can meet the needs of industrial production and commercial application of aqueous zinc ion battery and the like. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 is a cycle performance curve of a Zn / / Zn symmetric battery assembled by using the mixed electrolyte of Example 3 under the condition of a current density of 1 mA / cm 2 and a discharge depth of 1 mAh / cm 2 .

[0020] Figure 2 is a cycle performance curve of a Zn / / Zn symmetric battery assembled by using the mixed electrolyte of Example 4 under the condition of a current density of 25 mA / cm 2 and a discharge depth of 10 mAh / cm 2 . DETAILED DESCRIPTION

[0021] The application 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 effects of the application more clear and explicit, the application is further described in detail below.

[0022] The application 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 effects of the application more clear and explicit, the application is further described in detail below.

[0023] The additive includes a first compound containing an amino group and an imidazole group and a second compound containing a sulfonic acid group.

[0024] In the mixed electrolyte, the concentration of zinc ions is 0.3-10 mol / L, the total concentration of the amino group, the imidazole group and the sulfonic acid group is 0.06-1.2 mol / L, and the ratio of the sum of the molar amounts of the amino group and the imidazole group to the molar amount of the sulfonic acid group is (1-4):1.

[0025] Specifically, the mixed electrolyte contains an amino group, an imidazole group and a sulfonic acid group, and when used as an electrolyte of an aqueous zinc ion battery, the strong adsorption capacity among the amino group, the sulfonic acid group and the zinc ion in the mixed electrolyte and the reduction reaction (SO3 - + e - + Zn 2+= ZnSO3, 2N 2- + 2e - + 3Zn 2+ = Zn3N2), thereby depositing a layer of N and S-rich, dense and uniform gradient solid electrolyte film 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; wherein the amino group and the imidazole group simultaneously contribute to the formation of Zn3N2, which should be on the same compound, otherwise it is not conducive to the electron transfer reaction of N atoms, which will interfere with the reduction of N 2- , and the formed Zn3N2 is not uniform, the performance of the assembled Zn / / Zn symmetric battery is poor, 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.

[0026] In an embodiment, the zinc salt is selected from one or more of zinc sulfate, zinc trifluoromethane sulfonate, zinc chloride, zinc acetate, and zinc nitrate.

[0027] In an 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-nitroimidazolidine, 1,4-dimethyl-5-aminoimidazole hydrochloride, and 4-aminoimidazole-2-carboxylic acid ethyl ester.

[0028] In an embodiment, the second compound containing a sulfonic acid group is selected from one or more of allyl sulfonic acid sodium, propargyl sulfonic acid sodium, benzene sulfonic acid sodium, 1,5-naphthalene disulfonic acid sodium, xylene sulfonic acid sodium, hydroxymethyl sulfonic acid sodium, vinyl sulfonic acid sodium, polydithiodipropyl sulfonic acid sodium, butynol ether propane sulfonic acid sodium, and alkanol sulfonic acid sodium.

[0029] In an embodiment, the total concentration of the amino group and the imidazole group in the mixed electrolyte is 0.03-1 mol / L. Within the range of the total concentration of the amino group and the imidazole group in the mixed electrolyte, the strong adsorption ability between the amino group and the zinc ion, and the reduction of the amino group and the imidazole group during the discharge process can be utilized, thereby depositing a layer of N-rich, dense and uniform gradient solid electrolyte film on the surface of the zinc negative electrode, which not only hinders the corrosion of zinc, but also promotes the uniform deposition of zinc ions.

[0030] In an embodiment, the concentration of the sulfonic acid group in the mixed electrolyte is 0.03-0.2 mol / L. Within the range of the concentration of the sulfonic acid group in the mixed electrolyte, the S atom in the gradient solid electrolyte film can be provided, and the sulfonic acid group and the zinc ion have a strong binding energy, which can accelerate the desolvation process of the zinc ion and promote the uniform deposition and stripping of the zinc ion.

[0031] In an embodiment, the mixed electrolyte has a pH of 3.5-7.

[0032] The embodiment of the present application provides a preparation method of the mixed electrolyte, which comprises: dissolving a zinc salt and an additive in deionized water to obtain the mixed electrolyte.

[0033] The embodiment of the present application provides an application of the mixed electrolyte, which is applied to a water-based zinc ion battery.

[0034] The embodiment of the present application provides a water-based zinc ion battery comprising the mixed electrolyte.

[0035] In an embodiment, the water-based zinc ion battery comprises: a zinc electrode, a glass fiber diaphragm, and the mixed electrolyte containing amino groups, imidazole groups and sulfonic acid groups.

[0036] The present application is further described below through specific embodiments.

[0037] Embodiment 1

[0038] At room temperature, 0.09 mmol of 2-aminoimidazole and 0.06 mmol of 1,5-naphthalenedisulfonic acid sodium are added into 1 mL of 1 mol / L zinc sulfate solution, and after being mixed uniformly, a mixed electrolyte containing amino groups, imidazole groups and sulfonic acid groups is obtained.

[0039] Embodiment 2

[0040] At room temperature, 0.015 mmol of 2-aminoimidazole sulfate (containing 0.03 mmol of amino groups and 0.03 mmol of imidazole groups) and 0.03 mmol of propargyl sulfonic acid sodium are added into 1 mL of 1 mol / L zinc acetate solution, and after being mixed uniformly, a mixed electrolyte containing amino groups, imidazole groups and sulfonic acid groups is obtained.

[0041] Embodiment 3

[0042] At room temperature, 0.05 mmol of 2-aminoimidazole sulfate (containing 0.1 mmol of amino groups and 0.1 mmol of imidazole groups) and 0.05 mmol of propargyl sulfonic acid sodium are added into 1 mL of 1 mol / L zinc sulfate solution, and after being mixed uniformly, a mixed electrolyte containing amino groups, imidazole groups and sulfonic acid groups is obtained.

[0043] Embodiment 4

[0044] 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 allylsulfonate were added into 1 mL of 2 mol / L zinc sulfate / zinc sulfonate solution, and after mixing, a mixed electrolyte containing amino group, imidazole group and sulfonic acid group was obtained.

[0045] Example 5

[0046] At room temperature, 0.1 mmol of 2-aminoimidazole and 0.1 mmol of sodium allylsulfonate were added into 1 mL of 1 mol / L zinc sulfate solution, and after mixing, a mixed electrolyte containing amino group, imidazole group and sulfonic acid group was obtained.

[0047] Example 6

[0048] At room temperature, 0.1 mmol of 2-aminoimidazole and 0.05 mmol of sodium 1,5-naphthalenedisulfonate were added into 1 mL of 1 mol / L zinc trifluoromethanesulfonate solution, and after mixing, a mixed electrolyte containing amino group, imidazole group and sulfonic acid group was obtained.

[0049] Example 7

[0050] At room temperature, 0.1 mmol of 1,4-dimethyl-5-aminoimidazole hydrochloride and 0.08 mmol of sodium allylsulfonate were added into 1 mL of 1 mol / L zinc nitrate solution, and after mixing, a mixed electrolyte containing amino group, imidazole group and sulfonic acid group was obtained.

[0051] Comparative Example 1

[0052] At room temperature, 0.09 mmol of 2-aminoimidazole was added into 1 mL of 1 mol / L zinc sulfate solution, and after mixing, a mixed electrolyte containing amino group was obtained.

[0053] Comparative Example 2

[0054] At room temperature, 0.06 mmol of sodium 1,5-naphthalenedisulfonate was added into 1 mL of 1 mol / L zinc sulfate solution, and after mixing, a mixed electrolyte containing sulfonic acid group was obtained.

[0055] Comparative Example 3

[0056] At room temperature, 0.09 mmol of N-methylimidazole and 0.06 mmol of sodium 1,5-naphthalenedisulfonate were added into 1 mL of 1 mol / L zinc sulfate solution, and after mixing, a mixed electrolyte containing imidazole group and sulfonic acid group was obtained.

[0057] Performance Test

[0058] The mixed electrolyte of Examples 1-7 and Comparative Examples 1-3 was used as the electrolyte of a water-based zinc ion battery, a polished zinc sheet was used as the positive and negative electrodes, the effective area of the positive and negative electrodes was about 1.539 cm 2 , a glass fiber membrane was used as a separator, and a CR2032 type button-shaped zinc ion battery was assembled. The assembled Zn / / Zn symmetric battery was tested for electrochemical performance under different conditions using an electrochemical workstation, and the test results are shown in Table 1.

[0059] Table 1: Electrochemical performance test results of zinc ion battery

[0060]

[0061] In Table 1, test ① was: cycled at a current density of 1 mA / cm 2 and a discharge depth of 1 mAh / cm 2 ; test ② was: cycled at a current density of 5 mA / cm 2 and a discharge depth of 5 mAh / cm 2 ; test ③ was: cycled at a current density of 10 mA / cm 2 and a discharge depth of 10 mAh / cm 2 ; test ④ was: cycled at a current density of 20 mA / cm 2 and a discharge depth of 20 mAh / cm 2 ; and test ⑤ was: cycled at a current density of 40 mA / cm 2 and a discharge depth of 40 mAh / cm 2 .

[0062] In addition, the Zn / / Zn symmetric battery assembled using the mixed electrolyte of Example 3 was cycled at a current density of 1 mA / cm 2 and a discharge depth of 1 mAh / cm 2 , and the cycle performance curve is shown in Figure 1 , with a cycle length of up to 2600 hours. The Zn / / Zn symmetric battery assembled using the mixed electrolyte of Example 4 was cycled at a current density of 25 mA / cm 2 and a discharge depth of 10 mAh / cm 2 , and the cycle performance curve is shown in Figure 2 , with a cycle length of up to 428 hours.

[0063] In summary, the application 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, a zinc salt and an additive. The additive comprises 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, the total concentration of amino groups, imidazole groups and sulfonic acid groups is 0.06-1.2 mol / L, and 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 application contains amino groups, imidazole groups and sulfonic acid groups. When used as an electrolyte of a water-based zinc ion battery, the mixed electrolyte can utilize the strong adsorption capacity among the amino groups, sulfonic acid groups and zinc ions in the mixed electrolyte, and the reduction reactions of the amino groups, sulfonic acid groups and imidazole groups in 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 and other side reactions of the zinc negative electrode in the charge and discharge process. The amino groups and imidazole groups simultaneously contribute to the formation of Zn3N2, which should be on the same compound, otherwise the electron transfer of N atoms will be interfered, the reduction of N 2- will be interfered, and the formed Zn3N2 is non-uniform, the performance of the assembled Zn / / Zn symmetric battery is poor, and is not as good as the system in which the amino groups and imidazole groups are in the same compound. In addition, the sulfonic acid groups and zinc ions have strong binding energy, which can accelerate the desolvation process of zinc ions, thereby inducing uniform deposition and stripping.

[0064] The preparation method of the mixed electrolyte is simple, easy to operate, suitable for industrial production, and the cost of the additive is relatively low, which can meet the needs of industrial production and commercial application of water-based zinc ion batteries. In addition, the performance of the water-based zinc ion battery assembled with the mixed electrolyte is also excellent, and the cycle life of the water-based zinc battery can be significantly improved by using a small amount of additive, and the cost of the additive is lower than that of most additives.

[0065] It should be understood that the application of the application is not limited to the above examples, and those skilled in the art can make improvements or changes according to the above description, and all these improvements and changes shall belong to the protection scope of the appended claims of the application.

Claims

1. A mixed electrolyte containing an amino group, an imidazolyl group and a sulfonic acid group, characterized in that, 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 the amino group, the imidazole group, and the sulfonic acid group is 0.06-1.2 mol / L, and the ratio of the sum of the molar amounts of the amino group and the imidazole group to the molar amount of the sulfonic acid group is (1-4):

1. 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-nitroimidazolidine, 1,4-dimethyl-5-aminoimidazole hydrochloride, and 4-aminoimidazole-2-carboxylic acid ethyl ester. The second compound containing a sulfonic acid group is selected from one or more of allyl sodium sulfonate, propargyl sodium sulfonate, benzene sodium sulfinate, 1,5-naphthalene disulfonic acid sodium, xylene sodium sulfonate, sodium hydroxymethyl sulfonate, sodium vinyl sulfonate, sodium polydithiobispropane sulfonate, butynol ether propane sodium sulfonate, and sodium alkanol sulfonate.

2. The hybrid electrolyte of claim 1, wherein, The zinc salt is selected from one or more of zinc sulfate, zinc trifluoromethane sulfonate, zinc chloride, zinc acetate, and zinc nitrate.

3. The hybrid electrolyte of claim 1, wherein, In the mixed electrolyte, the total concentration of the amino group and the imidazole group is 0.03-1 mol / L.

4. The hybrid electrolyte of claim 1, wherein In the mixed electrolyte, the concentration of the sulfonic acid group is 0.03-0.2 mol / L.

5. The hybrid electrolyte of claim 1, wherein The pH of the mixed electrolyte is 3.5-7.

6. A method for preparing a hybrid electrolyte as claimed in any one of claims 1 to 5, characterized in that, The preparation method comprises dissolving the zinc salt and the additive in deionized water to obtain the mixed electrolyte.

7. Use of a hybrid electrolyte as claimed in any one of claims 1 to 5, characterized in that The mixed electrolyte is applied to a water-based zinc ion battery.

8. An aqueous zinc-ion battery, characterized in that, The application comprises the mixed electrolyte according to any one of claims 1-5.

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