Fluorine sulfonyl-dioxothiazolidine compound as well as preparation method and application thereof

Abstract

The invention provides a sulfonyl fluoride-dioxothiazolidine compound as well as a preparation method and application thereof. The sulfonyl fluoride-dioxothiazolidine compound has a structure as shown in a formula I in the specification. The preparation method of the fluorosulfonyl-dioxothiazolidine compound comprises the following steps: S1, enabling taurine and sodium bicarbonate to react in water to obtain sodium taurate; s2, reacting sodium taurate, a chlorination reagent, an acid-binding agent and a catalyst in a first solvent to obtain an intermediate A; s3, carrying out reflux reaction on the intermediate A and sodium ethoxide, and carrying out post-treatment to obtain an intermediate B; and S4, reacting the intermediate B and sulfonyl fluoride in a second solvent, and carrying out reduced pressure distillation to obtain the sulfonyl fluoride-dioxothiazolidine compound. The sulfonyl fluoride-dioxothiazolidine compound is novel in structure, mild in reaction condition and high in product purity, contains a sulfonyl fluoride group and a dioxothiazole structure, and can be applied to a lithium ion battery to improve the electrochemical performance of the lithium ion battery. Formula 1.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of compound synthesis, in particular to a preparation method and application of fluorosulfonyl-dioxothiazolidine compounds. BACKGROUND

[0002] Lithium ion batteries have the characteristics of high energy density, low self-discharge rate, wide use temperature range, long cycle life, environmental protection, memory effect, and large current charging and discharging, and are widely used in mobile phones, notebook computers, camcorders, digital cameras and other high-energy portable electronic devices, and have broad application prospects in new energy vehicles, aerospace, national defense equipment and other fields. At present, the mainstream commercial electrolyte is a liquid electrolyte (commonly known as electrolyte), which is mainly composed of solute lithium salt, organic solvent and additive. The electrolyte can be divided into solid electrolyte and liquid electrolyte (commonly known as electrolyte) from the physical form, and the electrolyte can be further divided into water-based electrolyte and organic (solvent) electrolyte based on the solvent type. The currently commercialized electrolyte is mainly an organic electrolyte, which is composed of solute (lithium salt), solvent (organic solvent) and additive.

[0003] The electrolyte is the blood of the lithium ion battery, which plays a role in transferring lithium ions between the positive and negative electrode materials and the separator. In addition, the electrolyte also plays an important role in the formation of SEI and CEI at the interface of the positive and negative electrode materials and the impedance size. It has been reported that adding some additives (such as organic additives VC, PS, DTD, TMSP; inorganic additives LiPO2F2, LiFSI, LiTFSI, LiPF2(C2O4)2, LiBOB, etc.) which can form a film at the interface of the ternary positive electrode material in the electrolyte can effectively protect the positive electrode, improve the pressure window of the electrolyte, and improve the cycle life of the battery. Studies have found that these additives not only form CEI at the interface of the positive electrode material, but also form SEI at the interface of the graphite negative electrode, resulting in an increase in the internal resistance of the battery, affecting the rate and low-temperature performance of the battery. However, compared with other additives, carbonate compounds have a lower oxidation potential, so they can form a dense CEI on the surface of the positive electrode material, effectively protecting the positive electrode material and reducing the degree of interface catalytic reaction; sulfur-containing additives have a lower reduction potential and can form SEI on the surface of the graphite negative electrode, and the SEI contains more lithium sulfate and alkyl lithium sulfate components, which have high electronic conductivity and ion conductivity, so the interface impedance of the negative electrode is smaller. Therefore, it is extremely important to continuously develop new sulfur-containing additive compounds for the continuous development of lithium ion batteries. SUMMARY

[0004] The purpose of this invention is to provide a fluorosulfonyl-dioxathiazoline compound, its preparation method, and its applications. The preparation method of this invention is simple to operate, has mild reaction conditions, and is easy to industrialize. Furthermore, this fluorosulfonyl-dioxathiazoline compound possesses a sulfonyl group and a nitrogen-containing fluorosulfonyl structure, and can be applied in lithium-ion batteries to improve their electrochemical performance.

[0005] To achieve the above objectives, the first aspect of the present invention provides a fluorosulfonyl-dioxathiazoline compound having the structure shown in Formula 1:

[0006] Formula 1.

[0007] Compared with the prior art, the fluorosulfonyl-dioxathiazoline compounds of the present invention have a special structure as shown in Formula 1, which contains fluorosulfonyl groups and dioxathiazoline structures, and have good application prospects. They can be applied to lithium-ion batteries to improve their electrochemical performance. A second aspect of the present invention provides a method for preparing the aforementioned fluorosulfonyl-dioxathiazoline compounds, comprising: S1 reacts taurine and sodium bicarbonate in water to obtain sodium taurate; S2 reacts the sodium taurate, chlorinating agent, acid-binding agent and catalyst in a first solvent to obtain intermediate A; S3 The intermediate A is refluxed with sodium ethoxide, and after post-processing, intermediate B is obtained; S4 The intermediate B and sulfonyl fluoride are reacted in a second solvent, and the fluorosulfonyl-dioxathiazoline compound is obtained by vacuum distillation.

[0008] A novel electrolyte additive was prepared by the method of the present invention. The preparation method is simple to operate, the reaction conditions are mild, the product obtained has high purity, and it is easy to industrialize.

[0009] As a preferred technical solution, in S1, the molar ratio of taurine to sodium bicarbonate is 1:0.9~1.2, the reaction temperature is 20℃~35℃, and the reaction time is 0.2h~2h.

[0010] As a preferred technical solution, in S2, the reaction includes first placing the sodium taurine, the catalyst, and the acid-binding agent in the first solvent and cooling it to -10℃~5℃, then slowly adding the chlorinating reagent and reacting at -10℃~30℃ for 2h~8h.

[0011] As a preferred technical solution, the molar ratio of sodium taurate, the chlorinating agent and the acid-binding agent is 1:1~1.5:3~6, and the amount of catalyst added is 0.001%~0.01% of the amount of the first solvent added.

[0012] As a preferred technical solution, the chlorinating agent is selected from at least one of triphosgene, diphosgene, phosgene, sulfonyl chloride, phosphorus trichloride and phosphorus oxychloride, the acid-binding agent is selected from at least one of triethylamine, pyridine and DBU, and the catalyst is potassium phosphate.

[0013] As a preferred technical solution, in S3, the reflux reaction includes first dissolving the intermediate A in ethanol, and then adding an ethanol solution of sodium ethoxide dropwise. The molar ratio of the intermediate A to the sodium ethoxide is 1:0.9~1.2. The temperature of the reflux reaction is 60℃~80℃, and the time of the reflux reaction is 6h~15h. The post-treatment specifically involves concentrating, extracting, and crystallizing the reaction solution.

[0014] As a preferred technical solution, in S4, the molar ratio of intermediate B to sulfonyl fluoride is 1:0.9~1.2, the reaction temperature is 20℃~35℃, the reaction time is 2h~6h, and the vacuum distillation temperature is 110℃~117℃.

[0015] As a preferred technical solution, the first solvent and the second solvent are each independently selected from at least one of dichloromethane, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1,4-dioxane, toluene, acetonitrile, diethyl ether, tetrahydrofuran, dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, and propylene carbonate.

[0016] A third aspect of this invention provides the application of the aforementioned fluorosulfonyl-dioxathiazoline compounds, or fluorosulfonyl-dioxathiazoline compounds prepared according to the aforementioned preparation method, in electrolyte additives. Applying the fluorosulfonyl-dioxathiazoline compounds of this invention to lithium-ion batteries can improve the electrochemical performance of lithium-ion batteries and has good application prospects. Detailed Implementation

[0017] The fluorosulfonyl-dioxathiazoline compounds of this invention can be used in materials, pharmaceutical intermediates, and other fields, and are particularly suitable for lithium-ion battery electrolytes. As a novel electrolyte additive, they can improve the electrochemical performance of lithium-ion batteries, such as cycle performance.

[0018] The fluorosulfonyl-dioxathiazoline compounds of the present invention have the structure shown in Formula 1:

[0019] Formula 1.

[0020] The method for preparing the fluorosulfonyl-dioxathiazoline compounds of the present invention includes: S1 reacts taurine and sodium bicarbonate in water to obtain sodium taurate; S2 reacts sodium taurate, chlorinating agent, acid-binding agent and catalyst in a first solvent to obtain intermediate A; S3 reacts intermediate A with sodium ethoxide under reflux, and then proceeds to obtain intermediate B after further processing; S4 reacts intermediate B and sulfonyl fluoride in a second solvent, and then distills under reduced pressure to obtain fluorosulfonyl-dioxathiazoline compounds.

[0021] Further, the reaction in S1 can be carried out with reference to reaction formula one. In S1, the molar ratio of taurine to sodium bicarbonate is 1:0.9 to 1.2, preferably 1:1. As an example, the molar ratio of taurine to sodium bicarbonate can be, but is not limited to, 1:0.9, 1:1, 1:1.1, or 1:1.2. The reaction temperature is 20°C to 35°C, and as an example, the reaction temperature can be, but is not limited to, 20°C, 22°C, 24°C, 25°C, 26°C, 28°C, 30°C, 32°C, 34°C, or 35°C. The reaction time is 0.2h to 2h, and as an example, the reaction time can be, but is not limited to, 0.2h, 0.4h, 0.5h, 0.8h, 1h, 1.2h, 1.4h, 1.6h, 1.8h, or 2h.

[0022]

[0023] Reaction 1 Furthermore, the reaction in S2 can be carried out with reference to reaction formula two. In S2, the reaction involves first placing sodium taurate, the catalyst, and the acid-binding agent in a first solvent and cooling to -10℃ to 5℃, then slowly introducing the chlorinating reagent and reacting at -10℃ to 30℃ for 2h to 8h. The molar ratio of sodium taurate, the chlorinating reagent, and the acid-binding agent is 1:1 to 1.5:3 to 6. As an example, the molar ratio of sodium taurate, the chlorinating reagent, and the acid-binding agent can be, but is not limited to, 1:1:3, 1:1:4, 1:1:5, 1:1:6, 1:1.2:3, 1:1.2:4, 1:1.2:5, 1:1.2:6, 1:1.4:3, 1:1.4:4, 1:1.4:5, 1:1.4:6, 1:1.5:3, 1:1.5:4, 1:1.5:5, and 1:1.5:6. The amount of catalyst added is 0.001% to 0.01% of the amount of the first solvent added. For example, the amount of catalyst added is 0.001%, 0.001%, 0.02%, 0.004%, 0.006%, 0.008%, or 0.01% of the amount of the first solvent added. The chlorinating agent is selected from at least one of triphosgene, diphosgene, phosgene, phosphorus trichloride, and phosphorus oxychloride. The acid-binding agent is selected from at least one of triethylamine, pyridine, and DBU, wherein DBU refers to 1,8-diazabicyclo[5.4.0]undec-7-ene. The catalyst is selected from potassium phosphate.

[0024]

[0025] Reaction 2 Furthermore, the reaction in S3 can be carried out with reference to reaction formula three. In S3, the reflux reaction specifically involves first dissolving intermediate A in ethanol, and then adding a sodium ethoxide ethanol solution dropwise. The molar ratio of intermediate A to sodium ethoxide is 1:0.9~1.2. As an example, the molar ratio of intermediate A to sodium ethoxide can be, but is not limited to, 1:0.9, 1:1, 1:1.1, or 1:1.2. The reflux reaction temperature is 60℃~80℃. As an example, the reflux reaction temperature can be, but is not limited to, 60℃, 65℃, 70℃, 75℃, or 80℃. The reflux reaction time is 6h~15h. As an example, the reflux reaction time can be, but is not limited to, 6h, 7h, 8h, 9h, 10h, 11h, 12h, 13h, 14h, or 15h. The post-treatment specifically involves concentrating, extracting, and crystallizing the reaction solution after the reaction is complete. Specifically, concentration can be achieved by using a rotary evaporator to evaporate the solvent to concentrate the reaction solution. Extraction can be performed using dichloromethane as the extraction solvent, but is not limited to this. Crystallization specifically involves first concentrating the extract until a small amount of solid precipitates, and then adding n-heptane dropwise to crystallize.

[0026]

[0027] Reaction 3 Furthermore, the reaction in S4 can be carried out with reference to reaction formula four. In S4, the molar ratio of intermediate B to sulfonyl fluoride is 1:0.9~1.2. As an example, the molar ratio of intermediate B to sulfonyl fluoride can be, but is not limited to, 1:0.9, 1:1, 1:1.1, or 1:1.2. The reaction temperature is 20℃~35℃. As an example, the reaction temperature can be, but is not limited to, 20℃, 22℃, 24℃, 26℃, 28℃, 30℃, 32℃, 34℃, or 35℃. The reaction time is 2h~6h. As an example, the reaction time can be, but is not limited to, 2h, 3h, 4h, 5h, or 6h. The temperature for vacuum distillation is 110℃~117℃. As an example, the temperature for vacuum distillation can be, but is not limited to, 110℃, 111℃, 112℃, 113℃, 114℃, 115℃, 116℃, or 117℃. The pressure for vacuum distillation can be, but is not limited to, 0.1 Pa.

[0028]

[0029] Reaction 4 In this invention, the first solvent and the second solvent are each independently selected from at least one of dichloromethane, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1,4-dioxane, toluene, acetonitrile, diethyl ether, tetrahydrofuran, dimethyl carbonate, methyl ethyl carbonate, diethyl carbonate, and propylene carbonate.

[0030] To better illustrate the purpose, technical solution, and beneficial effects of this invention, the invention will be further described below with reference to specific embodiments. It should be noted that the methods described below are further explanations of this invention and should not be construed as limiting it.

[0031] Example 1 This embodiment provides a fluorosulfonyl-dioxathiazoline compound having the structure shown in Formula 1:

[0032] Formula 1.

[0033] The method for preparing the fluorosulfonyl-dioxathiazoline compound in this embodiment includes: S1 125.14g taurine and 84g sodium bicarbonate were placed in 500g water and reacted at 25℃ for 0.5h. After concentration under reduced pressure to remove water, 147g sodium taurine was obtained. S2 147g sodium taurate, 300g triethylamine and 2g potassium phosphate were placed in 500ml dichloromethane and cooled to 0~5℃. Then, a dichloromethane solution of triphosgene (300g triphosgene dissolved in 600g dichloromethane) was slowly added dropwise. The reaction was carried out at 20℃ for 6h. After the reaction was completed, the dichloromethane was evaporated to obtain 97.6g intermediate A. S3 Dissolve 97.6g of intermediate A in 300g of ethanol, then add dropwise an ethanol solution of sodium ethoxide (46.2g dissolved in 200g of ethanol), heat to 80℃ and react for 10h. After the reaction is complete, concentrate the ethanol, then add 500ml of dichloromethane for extraction, concentrate the dichloromethane until a small amount of solid precipitates, and add n-heptane to crystallize, to obtain 51.8g of intermediate B.

[0034] S4. 51.8 g of intermediate B and 300 g of dichloromethane were placed in a reaction flask, 47.4 g of sulfonyl fluoride was introduced, and the reaction was carried out at 28 °C for 5 h. Then, vacuum distillation was performed at 112 °C to obtain 68.6 g of fluorosulfonyl-dioxathiazoline compounds. The overall yield was 36.2%, and the purity was 99%. ¹H NMR (400 MHz, CDCl₃, ppm): δ 3.69 (m, 2H), 3.23 (m, 2H). ¹³C {¹H} NMR (100 MHz, CDCl₃, ppm): δ 51.7, 30.3.

[0035] Example 2 This embodiment provides a fluorosulfonyl-dioxathiazoline compound having the structure shown in Formula 1:

[0036] Formula 1.

[0037] The method for preparing the fluorosulfonyl-dioxathiazoline compound in this embodiment includes: S1 125.14g taurine and 84g sodium bicarbonate were placed in 500g water and reacted at 25℃ for 0.5h. After concentration under reduced pressure to remove water, 147.2g sodium taurine was obtained. S2 147.2g sodium taurate, 250g pyridine and 2g potassium phosphate were placed in 500ml dichloromethane and cooled to 0~5℃. Then, a dichloromethane solution of triphosgene (298.7g triphosgene dissolved in 600g dichloromethane) was slowly added dropwise. The reaction was carried out at 20℃ for 8h. After the reaction was completed, the dichloromethane was evaporated to obtain 96.7g intermediate A. S3 Dissolve 96.7g of intermediate A in 300g of ethanol, then add dropwise a sodium ethoxide ethanol solution (45.9g dissolved in 200g of ethanol), heat to 80℃ and react for 10h. After the reaction is complete, concentrate the ethanol, then add 500ml of dichloromethane for extraction, concentrate the dichloromethane until a small amount of solid precipitates, and add n-heptane to crystallize, to obtain 50.2g of intermediate B.

[0038] S4. 50.2 g of intermediate B and 300 g of dichloromethane were placed in a reaction flask, 47.1 g of sulfonyl fluoride was introduced, and the reaction was carried out at 28 °C for 5 h. Then, vacuum distillation was performed at 112 °C to obtain 62.4 g of fluorosulfonyl-dioxathiazoline compounds. The overall yield was 32.9%, and the purity was 99%. ¹H NMR (400 MHz, CDCl₃, ppm): δ 3.67 (m, 2H), 3.21 (m, 2H). ¹³C NMR (100 MHz, CDCl₃, ppm): δ 51.6, 30.3.

[0039] Example 3 This embodiment provides a fluorosulfonyl-dioxathiazoline compound having the structure shown in Formula 1:

[0040] Formula 1.

[0041] The method for preparing the fluorosulfonyl-dioxathiazoline compound in this embodiment includes: S1 125.14g taurine and 84g sodium bicarbonate were placed in 500g water and reacted at 25℃ for 0.5h. After concentration under reduced pressure to remove water, 146.8g sodium taurate was obtained. S2 146.8g sodium taurate, 300g triethylamine and 2g potassium phosphate were placed in 500ml dichloromethane and cooled to 0~5℃. Then 197.8g sulfonyl chloride was slowly added and reacted at 20℃ for 6h. After the reaction was completed, the dichloromethane was dried by rotary evaporation to obtain 76.9g intermediate A. S3 Dissolve 76.9g of intermediate A in 300g of ethanol, then add dropwise a sodium ethoxide ethanol solution (39.1g dissolved in 200g of ethanol), heat to 80℃ and react for 10h. After the reaction is complete, concentrate the ethanol, then add 500ml of dichloromethane for extraction, concentrate the dichloromethane until a small amount of solid precipitates, and add n-heptane to crystallize, to obtain 40.2g of intermediate B.

[0042] S4. 40.2 g of intermediate B and 300 g of dichloromethane were placed in a reaction flask, 47.4 g of sulfonyl fluoride was introduced, and the reaction was carried out at 28 °C for 5 h. Then, vacuum distillation was performed at 112 °C to obtain 47.8 g of a fluorosulfonyl-dioxathiazoline compound. The overall yield was 25.2%, and the purity was 99%. ¹H NMR (400 MHz, CDCl₃, ppm): δ 3.64 (m, 2H), 3.18 (m, 2H). ¹³C NMR (100 MHz, CDCl₃, ppm): δ 51.6, 30.2. The fluorosulfonyl-dioxathiazoline compounds shown in Formula 1 of Examples 1-3 were applied to lithium-ion batteries according to the following preparation method for lithium-ion non-aqueous electrolytes.

[0043] In an argon-filled glove box (H2O < 10 ppm, Ar > 99.99%), ethylene carbonate (EC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC) were mixed uniformly at a mass ratio of 1:2:1 to obtain a mixed solvent as a non-aqueous organic solvent. Then, 1% of the total weight of the non-aqueous electrolyte for lithium batteries and a fluorosulfonyl-dioxazoline compound prepared by the methods in Examples 1-3 were added to obtain a mixture. Lithium hexafluorophosphate was slowly added to the mixture until the molar concentration reached 1 mol / L. After mixing uniformly, non-aqueous electrolytes 1# to 3# were prepared.

[0044] In an argon-filled glove box (H2O < 10 ppm, Ar > 99.99%), ethylene carbonate (EC), diethyl carbonate (DEC), and ethyl methyl carbonate (EMC) are mixed evenly in a mass ratio of 1:2:1. The resulting mixed solvent is used as a non-aqueous organic solvent. Lithium hexafluorophosphate is slowly added to the non-aqueous organic solvent until the molar concentration is 1 mol / L. After mixing evenly, non-aqueous electrolyte 4# is prepared.

[0045] Lithium cobalt oxide was used as the positive electrode material and lithium metal as the counter electrode. Non-aqueous electrolytes 1#~4# were injected to assemble coin cells 1#~4#. Under normal temperature (25℃) conditions, the coin cells were subjected to one 3.0C / 3.0C charge and discharge cycle (battery discharge capacity recorded as C0), with an upper limit voltage of 4.2V. Then, they were subjected to 300 cycles of 3.0C / 3.0C charge and discharge (battery discharge capacity recorded as C1), and the capacity retention rate was calculated.

[0046] Capacity retention rate = (Battery capacity after 300 cycles C1 / Initial battery capacity C0) × 100% Table 1. Electrochemical performance test results for each example.

[0047] As shown in Table 1, the cycle performance of coin cells 1# to 3# is better than that of coin cell 4#. This is because the electrolytes of coin cells 1# to 3# contain fluorosulfonyl-dioxatazolidine compounds, and the fluorosulfonyl and dioxatazolidine structures they contain can improve the cycle performance of lithium-ion batteries.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, it is not limited to those listed in the embodiments. Those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A fluorosulfonyl-dioxathiazoline compound, characterized in that, It has the structure shown in Formula 1: Formula 1.

2. The method for preparing fluorosulfonyl-dioxathiazoline compounds according to claim 1, characterized in that, include: S1 reacts taurine and sodium bicarbonate in water to obtain sodium taurate; S2 reacts the sodium taurate, chlorinating agent, acid-binding agent and catalyst in a first solvent to obtain intermediate A; S3 The intermediate A is refluxed with sodium ethoxide, and after post-processing, intermediate B is obtained; S4 The intermediate B and sulfonyl fluoride are reacted in a second solvent, and then the fluorosulfonyl-dioxathiazoline compound is obtained by vacuum distillation.

3. The method for preparing fluorosulfonyl-dioxathiazoline compounds according to claim 2, characterized in that, In S1, the molar ratio of taurine to sodium bicarbonate is 1:0.9~1.2, the reaction temperature is 20℃~35℃, and the reaction time is 0.2h~2h.

4. The method for preparing fluorosulfonyl-dioxathiazoline compounds according to claim 2, characterized in that, In S2, the reaction includes first placing the sodium taurine, the catalyst, and the acid-binding agent in the first solvent and cooling it to -10℃~5℃, then slowly adding the chlorinating reagent and reacting at -10℃~30℃ for 2h~8h.

5. The method for preparing fluorosulfonyl-dioxathiazoline compounds according to claim 2, characterized in that, The molar ratio of sodium taurate, the chlorinating agent, and the acid-binding agent is 1:1 to 1.5:3 to 6, and the amount of catalyst added is 0.001% to 0.01% of the amount of the first solvent added.

6. The method for preparing fluorosulfonyl-dioxathiazoline compounds according to claim 2, characterized in that, The chlorinating agent is selected from at least one of triphosgene, diphosgene, phosgene, phosphorus trichloride and phosphorus oxychloride, the acid-binding agent is selected from at least one of triethylamine, pyridine and DBU, and the catalyst is potassium phosphate.

7. The method for preparing fluorosulfonyl-dioxathiazoline compounds according to claim 2, characterized in that, In S3, the reflux reaction includes first dissolving the intermediate A in ethanol, and then adding an ethanol solution of sodium ethoxide dropwise. The molar ratio of intermediate A to sodium ethoxide is 1:0.9~1.

2. The temperature of the reflux reaction is 60℃~80℃, and the time of the reflux reaction is 6h~15h. The post-treatment specifically involves concentrating, extracting, and crystallizing the reaction solution.

8. The method for preparing fluorosulfonyl-dioxathiazoline compounds according to claim 2, characterized in that, In S4, the molar ratio of intermediate B to sulfonyl fluoride is 1:0.9~1.2, the reaction temperature is 20℃~35℃, the reaction time is 2h~6h, and the vacuum distillation temperature is 110℃~117℃.

9. The method for preparing fluorosulfonyl-dioxathiazoline compounds according to claim 2, characterized in that, The first solvent and the second solvent are each independently selected from at least one of dichloromethane, N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, 1,4-dioxane, toluene, acetonitrile, diethyl ether, tetrahydrofuran, dimethyl carbonate, ethyl methyl carbonate, diethyl carbonate, and propylene carbonate.

10. The use of the fluorosulfonyl-dioxothiazoline compound according to claim 1 or the fluorosulfonyl-dioxothiazoline compound prepared by any one of the preparation methods of claims 2 to 9 in electrolyte additives.

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