Preparation method of fluoroether, electrolyte, battery and electric device

Abstract

The invention discloses a preparation method of fluoroether, an electrolyte, a battery and a power utilization device. The preparation method of the fluoro-ether comprises the following steps: reacting a compound A with an alkaline substance B in an organic solvent to obtain a mixture containing an intermediate product C; and reacting the mixture containing the intermediate product C with difluoromethane under the catalytic action of a catalyst to obtain fluoroether. The invention relates to the technical field of batteries, in particular to a preparation method of fluoroether, an electrolyte, a battery and a power utilization device. The preparation method comprises the following steps: reacting an alkaline substance with a compound A to generate a mixture containing an intermediate product C, and reacting the mixture containing the intermediate product C with difluoromethane and a catalyst to obtain fluoroether of which both ends are substituted by two fluorine atoms. The reaction conditions are mild, the process is simple, and the product yield is high.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and particularly to a preparation method of fluoroether, an electrolyte, a battery, and an electrical device. Background Art

[0002] Currently, the main method for synthesizing fluoroether is to react an alcohol or phenolic substance with a fluoroolefin in the presence of a catalyst under the condition of having or not having a solvent to obtain a fluoroether reaction solution. Fluoroolefins are not easily obtained, have a high cost, and are somewhat dangerous, which affects the synthesis of fluoroether. Summary of the Invention

[0003] The present application is made in view of the above problems, and its purpose is to provide a preparation method of fluoroether with easily available raw materials, reduced costs, and milder reaction conditions.

[0004] To achieve the above purpose, the embodiments of the present application provide a preparation method of fluoroether, an electrolyte, a battery, and an electrical device.

[0005] In a first aspect, the embodiments of the present application propose a preparation method of fluoroether, including the following steps:

[0006] React compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate product C;

[0007] React the mixture containing intermediate product C with difluoromethane under the catalysis of a catalyst to obtain fluoroether;

[0008] Wherein, compound A has a structural formula as shown in (Ⅰ), intermediate product C has a structural formula as shown in (Ⅱ), and fluoroether has a structural formula as shown in (Ⅲ):

[0009]

[0010] n is a positive integer from 1 to 20;

[0011] M includes at least one of lithium, sodium, and potassium.

[0012] Thus, in the technical scheme of the embodiment of the present application, an alkaline substance is reacted with compound A to generate a mixture containing intermediate product C, and the mixture containing intermediate product C is reacted with difluoromethane and a catalyst to obtain a fluoroether having two fluorine atoms substituted at both ends. The raw materials of the present application are easy to obtain and the cost is low; the reaction conditions are mild, the process is simple, and the product yield is high. If the value of n is greater than 20, the reactivity of compound A will decrease, the reaction rate is slow, and the yield of the mixture containing intermediate product C is low; when M is lithium, sodium, or potassium, the reaction rate with reactant A is good, which is conducive to the reaction to move in the direction of generating intermediate product C, and is conducive to the generation of a mixture containing intermediate product C. Difluoromethane has only one carbon atom that can form a solvated structure with lithium salts, and it is easier to dissociate lithium salts into positive ions and negative ions, which is conducive to the removal and embedding of lithium ions. It is easier to replace the alkali metal atoms at the ends of the mixture containing intermediate product C, and the efficiency of generating double-ended difluoro-substituted fluoroethers is higher.

[0013] In any embodiment, n is a positive integer of 2 to 8. Within this range, the reaction activity of compound A is stronger, which is more conducive to the generation of intermediate substance C and improves the reaction efficiency.

[0014] In any embodiment, the difluoromethane comprises CHF2X, wherein X is selected from any one of chlorine, bromine and iodine. The alcoholic hydroxyl group can form an alcohol anion under alkaline conditions to attack the carbon positive center of the halogenated hydrocarbon, and the halogenated hydrocarbon removes the halogen to form an ether bond, which is more conducive to the replacement of alkali metal elements by fluorine atoms and improves the efficiency of the synthesis of double-terminal difluoro ethers.

[0015] In any embodiment, the alkaline substance B includes a hydroxide-containing compound. The hydroxide-containing compound B can react with the compound A to generate water, and removing the water is beneficial to generate a mixture containing the intermediate product C, thereby improving the efficiency of the synthesis.

[0016] In any embodiment, the hydroxide-containing compound includes an alkali metal hydroxide compound. The alkali metal hydroxide compound is easy to obtain and inexpensive, and can further improve the synthesis efficiency of the mixture containing the intermediate product C.

[0017] In any embodiment, the alkali metal-containing hydroxide compound includes at least one of lithium hydroxide, sodium hydroxide and potassium hydroxide. When M is lithium, sodium or potassium, the reaction rate with reactant A is good, which is conducive to the reaction moving in the direction of generating intermediate product C and the generation of a mixture containing intermediate product C. Hydroxide-containing compound B can react with compound A to generate water, which is conducive to the generation of a mixture containing intermediate product C after removing water, thereby improving the efficiency of synthesis. Alkali metal-containing hydroxide compounds can further improve the synthesis efficiency of the mixture containing intermediate product C.

[0018] In any embodiment, the organic solvent includes, but is not limited to, at least one of benzene, toluene, xylene, acetonitrile, N,N-dimethylformamide, n-hexane, and cyclohexane. By using at least one of the above organic solvents, the water generated from the reaction of compound A and compound B can be carried out. Utilizing the characteristic that the boiling point of the solvent is close to that of water and the characteristic of the solvent to entrain water, the synthesis efficiency of the mixture containing intermediate C can be improved; and / or,

[0019] The catalyst includes at least one of sodium iodide, magnesium iodide, potassium iodide, zinc iodide, sodium bromide, magnesium bromide, potassium bromide, and zinc bromide. By using at least one of the above catalysts, the synthesis efficiency of the bis-terminal difluoroether can be improved.

[0020] In any embodiment, in the reaction of compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate C: the mass ratio of the organic solvent, basic substance B, and compound A is (1-20):(0.2-3):1. Within this mass ratio range, it is beneficial to improve the yield of the mixture containing intermediate C; optionally, the mass ratio of the organic solvent, basic substance B, and compound A is (2-10):(0.5-2):1, which can further improve the yield of the mixture containing intermediate C; and / or,

[0021] In any embodiment, in the reaction of the mixture containing intermediate C with difluoromethane under the catalysis of a catalyst to obtain a fluoroether: the mass ratio of difluoromethane, catalyst, and the mixture containing intermediate C is (0.1-4):(0.001-0.1):(2-22). Within this mass ratio range, the yield of the fluoroether can be improved; optionally, the mass ratio of difluoromethane, catalyst, and the mixture containing intermediate C is (0.8-3):(0.008-0.08):(3-11), which can further improve the yield of the fluoroether.

[0022] In any embodiment, in the reaction of compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate C:

[0023] The reaction temperature is -20 to 150 °C. Within this reaction temperature range, the yield and reaction rate of the mixture containing intermediate C can be improved, while the occurrence of side reactions and the generation of by-products can be reduced; optionally, the reaction temperature is 30 to 80 °C, which can further improve the yield and reaction rate of the mixture containing intermediate C, while further reducing the occurrence of side reactions and further reducing the generation of by-products; and / or,

[0024] The reaction time is 0.5 to 8 h. Within this reaction time range, the yield and reaction rate of the mixture containing intermediate C can be increased, while the occurrence of side reactions can be reduced and the generation of by-products can be decreased. Optionally, the reaction time is 1 to 4 h, which can further increase the yield and reaction rate of the mixture containing intermediate C, while reducing the occurrence of side reactions and decreasing the generation of by-products.

[0025] In any embodiment, in the reaction of the mixture containing intermediate C with difluoromethane under the catalysis of a catalyst to obtain a fluoroether:

[0026] The reaction temperature is 0 to 150 °C. Within this reaction temperature range, the yield and reaction rate of the fluoroether can be increased, while the occurrence of side reactions can be reduced and the generation of by-products can be decreased. Optionally, the reaction temperature is 20 to 80 °C, which can further increase the yield and reaction rate of the fluoroether, while reducing the occurrence of side reactions and decreasing the generation of by-products; and / or,

[0027] The reaction time is 0.5 to 10 h. Within this reaction time, the yield and reaction rate of the fluoroether can be increased, while the occurrence of side reactions can be reduced and the generation of by-products can be decreased. Optionally, the reaction time is 1 to 6 h, which can further increase the yield and reaction rate of the fluoroether, while reducing the occurrence of side reactions and decreasing the generation of by-products; and / or,

[0028] The reaction pressure is 0.1 to 5 MPa. Within this pressure range, the concentration of difluoromethane can be increased, the reaction rate and the yield of the fluoroether can be increased, while the heat release amount can be controlled and the risk of thermal runaway can be reduced. Optionally, the reaction pressure is 0.2 to 3 MPa, which can further increase the concentration of difluoromethane, increase the reaction rate and the yield of the fluoroether, increase the reaction rate while controlling the heat release amount, and reduce the risk of thermal runaway.

[0029] In any embodiment, the reaction of the mixture containing intermediate C with difluoromethane under the catalysis of a catalyst to obtain a fluoroether includes:

[0030] React the mixture containing intermediate C with difluoromethane in an organic solvent in the presence of a catalyst, centrifuge the reaction product, and take the upper layer liquid, which is washed, dried, and rectified to obtain the fluoroether.

[0031] In a second aspect, an electrolyte solution is provided in an embodiment of the present application, which includes the fluoroether prepared by the method for preparing a fluoroether according to the first aspect of the present application.

[0032] In a third aspect, a battery is provided in an embodiment of the present application, which includes the electrolyte solution according to the second aspect of the present application.

[0033] Fourthly, an embodiment of the present application provides an electrical device, including the battery of the third aspect of the present application. Description of the Drawings

[0034] Figure 1 is a schematic diagram of a secondary battery according to an embodiment of the present application.

[0035] Figure 2 is Figure 1 an exploded view of the secondary battery according to an embodiment of the present application shown in the figure.

[0036] Figure 3 is a schematic diagram of a battery module according to an embodiment of the present application.

[0037] Figure 4 is a schematic diagram of a battery pack according to an embodiment of the present application.

[0038] Figure 5 is Figure 4 an exploded view of the battery pack according to an embodiment of the present application shown in the figure.

[0039] Figure 6 is a schematic diagram of an electrical device using a secondary battery as a power source according to an embodiment of the present application.

[0040] Figure 7 is the gas chromatography-mass spectrometry (GC-MS) spectrum of the fluoroether prepared in Example 1 of the present application.

[0041] Description of the Reference Numerals:

[0042] 1 battery pack; 2 upper box body; 3 lower box body; 4 battery module; 5 secondary battery; 51 housing; 52 electrode assembly; 53 top cover assembly. Detailed Embodiments

[0043] Hereinafter, embodiments of the preparation method, electrolyte, battery, and electrical device of the fluoroether of the present application are specifically disclosed. However, there may be cases where unnecessary detailed descriptions are omitted. For example, detailed descriptions of well-known matters and repeated descriptions of actually identical structures are omitted. This is to prevent the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art. In addition, the drawings and the following description are provided for those skilled in the art to fully understand the present application and are not intended to limit the subject matter recited in the claims.

[0044] The "ranges" disclosed in this application are defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of a particular range. The ranges defined in this way can include or exclude the end values, and can be combined arbitrarily, that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60 - 120 and 80 - 110 are listed for a specific parameter, ranges of 60 - 110 and 80 - 120 are also contemplated. In addition, if the minimum range values 1 and 2 are listed, and if the maximum range values 3, 4, and 5 are listed, the following ranges are all contemplated: 1 - 3, 1 - 4, 1 - 5, 2 - 3, 2 - 4, and 2 - 5. In this application, unless otherwise specified, the numerical range "a - b" represents an abbreviated representation of any real number combination between a and b, where a and b are both real numbers. For example, the numerical range "0 - 5" means that all real numbers between "0 - 5" are fully listed herein, and "0 - 5" is only an abbreviated representation of these numerical combinations. Additionally, when stating that a certain parameter is an integer ≥2, it is equivalent to disclosing that the parameter is, for example, the integers 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0045] If there is no special instruction, all embodiments and optional embodiments of this application can be combined with each other to form new technical solutions.

[0046] If there is no special instruction, all technical features and optional technical features of this application can be combined with each other to form new technical solutions.

[0047] If there is no special instruction, all steps of this application can be carried out sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method can include steps (a) and (b) carried out sequentially, or can also include steps (b) and (a) carried out sequentially. For example, when it is mentioned that the method may further include step (c), it means that step (c) can be added to the method in any order. For example, the method can include steps (a), (b), and (c), or can also include steps (a), (c), and (b), or can also include steps (c), (a), and (b), etc.

[0048] Currently, the main method for synthesizing fluoroethers is to react alcohols or phenols with fluoroolefins in the presence of a catalyst under solvent or solvent - free conditions to obtain a fluoroether reaction solution. Fluoroolefins are difficult to obtain, have a high cost, and are somewhat dangerous, which affects the synthesis of fluoroethers.

[0049] Therefore, there has been an endless stream of research on the synthesis of fluoroethers. For example, a production method of a fluoroether: reacting a raw material with a fluoroolefin in the presence of a catalyst with or without a solvent to obtain a fluoroether reaction solution, where the raw material is an alcohol or a phenolic substance, concentrating the fluoroether reaction solution to obtain a concentrated solution and a clear solution, and subjecting the clear solution to purification and separation to obtain a fluoroether product. However, the above-mentioned fluoroolefins are not easily obtained, have a high cost, and are somewhat dangerous, and are not suitable for the synthesis of fluoroether F2HCO(C2H4O)nCHF2.

[0050] Surprisingly, by reacting glycol or ethylene glycol with a basic substance to form an intermediate substance, and reacting the intermediate substance with a difluorohydrocarbon, a fluoroether can be formed. The reaction conditions are mild and the yield is high.

[0051] Based on this, the present application provides a method for preparing a fluoroether, an electrolyte, a battery, and an electrical device.

[0052] In a first aspect, an embodiment of the present application provides a method for preparing a fluoroether, including the following steps:

[0053] Reacting compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate product C;

[0054] Reacting the mixture containing intermediate product C with difluoromethane under the catalysis of a catalyst to obtain a fluoroether;

[0055] Wherein, compound A has a structural formula as shown in (Ⅰ), intermediate product C has a structural formula as shown in (Ⅱ), and the fluoroether has a structural formula as shown in (Ⅲ):

[0056]

[0057] n is a positive integer from 1 to 20;

[0058] M includes at least one of lithium, sodium, and potassium.

[0059] Thus, in the technical solution of the embodiment of the present application, an intermediate product is generated by reacting an alkaline substance with polyether alcohol or diol. The intermediate product reacts with difluoromethane and a catalyst to obtain a fluoroether with two fluorine atoms substituted at both ends. The raw materials of the present application are easily available and the cost is low; the reaction conditions are mild, the process is simple, and the product yield is high. When the value of n is greater than 20, the reaction activity of compound A will decrease, the reaction rate will be slow, and the yield of the mixture containing intermediate product C will be low; when M is lithium, sodium, or potassium, the reaction rate with reactant A is better, which is conducive to the reaction moving in the direction of generating intermediate product C and conducive to the formation of the mixture containing intermediate product C. Difluoromethane has only one carbon atom that can form a solvation structure with the lithium salt, making it easier to dissociate the lithium salt into positive and negative ions, which is beneficial to the extraction and insertion of lithium ions. It is easier to replace the alkali metal atoms at the ends of the mixture containing intermediate product C, and the efficiency of generating a double-terminal difluoro-substituted fluoroether is higher.

[0060] The value of n can be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20.

[0061] In any implementation manner, n is a positive integer from 2 to 8. Within this range, the reaction activity of compound A is stronger, which is more conducive to the formation of intermediate substance C and improves the reaction efficiency.

[0062] In any implementation manner, the difluoromethane includes CHF2X, where X is selected from any one of chlorine, bromine, and iodine. This can enable the alcohol hydroxyl group to form an alcohol anion under alkaline conditions, attack the carbon positive center of the halogenated hydrocarbon, and the halogenated hydrocarbon removes the halogen to form an ether bond, which is more conducive to the substitution of fluorine atoms for alkali metal elements and improves the synthesis efficiency of double-terminal difluoroethers.

[0063] When the difluoromethane includes CHF2X, the fluoroether has the reaction formulas shown in (1) and (2):

[0064]

[0065]

[0066] In any implementation manner, the alkaline substance B includes a compound containing a hydroxide group. The compound B containing a hydroxide group can react with compound A to generate water. After removing the water, it is conducive to the formation of the mixture containing intermediate product C and improves the synthesis efficiency.

[0067] In any embodiment, the hydroxide-containing compound includes an alkali metal hydroxide compound. When M is lithium, sodium, or potassium, the reaction rate with reactant A is relatively good, which is conducive to the reaction moving in the direction of forming intermediate product C and facilitating the formation of a mixture containing intermediate product C. The hydroxide-containing compound B can react with compound A to generate water. After removing the water, it is beneficial to the formation of a mixture containing intermediate product C and improves the synthesis efficiency. The alkali metal hydroxide compound can further improve the synthesis efficiency of the mixture containing intermediate product C.

[0068] In any embodiment, the alkali metal hydroxide compound includes but is not limited to at least one of lithium hydroxide, sodium hydroxide, and potassium hydroxide. Using the above-mentioned alkali metal hydroxide compound as the raw material is easily available and inexpensive, and at the same time, it can further improve the synthesis efficiency of the mixture containing intermediate product C.

[0069] In any embodiment, the organic solvent includes but is not limited to at least one of benzene, toluene, xylene, acetonitrile, N,N-dimethylformamide, n-hexane, and cyclohexane. By using at least one of the above-mentioned organic solvents, the water generated from the reaction of compound A and compound B can be carried out. Utilizing the characteristic that the boiling point of the solvent is close to that of water and the water-entraining property of the solvent, the synthesis efficiency of the mixture containing intermediate product C can be improved.

[0070] In any embodiment, the catalyst includes but is not limited to at least one of sodium iodide, magnesium iodide, potassium iodide, zinc iodide, sodium bromide, magnesium bromide, potassium bromide, and zinc bromide. Using at least one of the above-mentioned catalysts can improve the synthesis efficiency of bis-terminal difluoroether.

[0071] In any embodiment, when reacting compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate product C: the mass ratio of the organic solvent, basic substance B, and compound A is (1-20):(0.2-3):1. Within this mass ratio range, it is beneficial to improve the yield of the mixture containing intermediate product C. The mass ratio of the organic solvent, basic substance B, and compound A can be 1:0.2:1, 1:3:1, 20:0.2:1, 20:3:1, 2:0.5:1, 2:2:1, 10:0.5:1, 10:2:1, or 6:1.2:1; the proportion of the organic solvent within this ratio range can maintain the viscosity of the reaction system, making the mass transfer rate and reaction rate within a suitable range. The proportion of basic substance B within this range can make compound A react more completely and improve the mass transfer efficiency. Optionally, the mass ratio of the organic solvent, basic substance B, and compound A is (2-10):(0.5-2):1, which can further improve the yield of the mixture containing intermediate product C.

[0072] In any embodiment, when reacting the mixture containing intermediate C with difluoromethane under the catalysis of a catalyst to obtain a fluoroether, the mass ratio of the difluoromethane, the catalyst, and the mixture containing intermediate C is (0.1 - 4):(0.001 - 0.1):(2 - 22). Within this mass ratio range, the yield of the fluoroether can be increased. The mass ratio of the difluoromethane, the catalyst, and the mixture containing intermediate C can be 0.1:0.001:2, 0.1:0.1:2, 0.1:0.001:22, 0.1:0.1:22, 4:0.001:2, 4:0.001:22, 4:0.1:2, 4:0.1:22, 0.8:0.008:3, 0.8:0.008:11, 8:0.08:3, 8:0.08:11, 3:0.008:3, 3:0.008:11, 3:0.08:3, 3:0.08:11, or 2:0.05:5. When the proportion of difluoromethane is within this range, intermediate C can react completely, side reactions can be reduced, and the product yield can be increased. When the proportion of the catalyst is within this range, the catalytic effect can be improved, side reactions can be reduced, and the product yield can be increased. Optionally, the mass ratio of the difluoromethane, the catalyst, and the mixture containing intermediate C is (0.8 - 3):(0.008 - 0.08):(3 - 11), which can further increase the yield of the fluoroether.

[0073] In any embodiment, when reacting compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate C, the reaction temperature is -20 to 150°C. Within this reaction temperature range, the yield and reaction rate of the mixture containing intermediate C can be increased, while the occurrence of side reactions and the generation of by-products can be reduced. The reaction temperature can be -20°C, -10°C, 0°C, 10°C, 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C. Optionally, the reaction temperature is 30 to 80°C, which can further increase the yield and reaction rate of the mixture containing intermediate C, while reducing the occurrence of side reactions and the generation of by-products.

[0074] In any embodiment, when reacting compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate C, the reaction time is 0.5 to 8 h. Within this reaction time range, the yield and reaction rate of the mixture containing intermediate C can be increased, while the occurrence of side reactions and the generation of by-products can be reduced. The reaction time can be 0.5 h, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, or 8 h. Optionally, the reaction time is 1 to 4 h, which can further increase the yield and reaction rate of the mixture containing intermediate C, while reducing the occurrence of side reactions and the generation of by-products.

[0075] In any embodiment, when the mixture containing intermediate C reacts with difluoromethane under the catalysis of a catalyst to obtain a fluoroether, the reaction temperature is 0 to 150 °C. Within this reaction temperature range, the yield and reaction rate of the fluoroether can be increased, while the occurrence of side reactions can be reduced and the generation of by-products can be decreased. The reaction temperature can be 0 °C, 10 °C, 20 °C, 30 °C, 40 °C, 50 °C, 60 °C, 70 °C, 80 °C, 90 °C, 100 °C, 110 °C, 120 °C, 130 °C, 140 °C or 150 °C; optionally, the reaction temperature is 20 to 80 °C, which can further increase the yield and reaction rate of the fluoroether, while reducing the occurrence of side reactions and the generation of by-products.

[0076] In any embodiment, when the mixture containing intermediate C reacts with difluoromethane under the catalysis of a catalyst to obtain a fluoroether, the reaction time is 0.5 to 10 h. Within this reaction time, the yield and reaction rate of the fluoroether can be increased, while the occurrence of side reactions can be reduced and the generation of by-products can be decreased. The reaction time can be 0.5 h, 1 h, 2 h, 3 h, 4 h, 5 h, 6 h, 7 h, 8 h, 9 h or 10 h; optionally, the reaction time is 1 to 6 h, which can further increase the yield and reaction rate of the fluoroether, while reducing the occurrence of side reactions and the generation of by-products.

[0077] In any embodiment, when the mixture containing intermediate C reacts with difluoromethane under the catalysis of a catalyst to obtain a fluoroether, the reaction pressure is 0.1 to 5 MPa. Within this pressure range, the concentration of difluoromethane can be increased, the reaction rate and the yield of the fluoroether can be increased, while the heat release can be controlled and the risk of thermal runaway can be reduced. The reaction pressure can be 0.1 MPa, 0.2 MPa, 0.5 MPa, 1 MPa, 1.5 MPa, 2 MPa, 2.5 MPa, 3 MPa, 3.5 MPa, 4 MPa, 4.5 MPa or 5 MPa; optionally, the reaction pressure is 0.2 to 3 MPa, which can further increase the concentration of difluoromethane, increase the reaction rate and the yield of the fluoroether, increase the reaction rate and control the heat release at the same time, and reduce the risk of thermal runaway.

[0078] In any embodiment, when the mixture containing intermediate C reacts with difluoromethane under the catalysis of a catalyst to obtain a fluoroether, it includes: reacting the mixture containing intermediate C with difluoromethane in an organic solvent in the presence of a catalyst, centrifuging the reaction product, and taking the upper layer liquid, which is washed, dried and rectified to obtain the fluoroether.

[0079] In a second aspect, an electrolyte solution is provided in an embodiment of the present application, which includes the fluoroether prepared by the method for preparing a fluoroether according to the first aspect of the present application.

[0080] In a third aspect, an embodiment of the present application provides a battery, including the electrolyte of the second aspect of the present application.

[0081] In any implementation, the battery includes a primary battery or a secondary battery.

[0082] In an embodiment of the present application, a secondary battery is provided. Generally, a secondary battery includes a positive electrode sheet, a negative electrode sheet, an electrolyte, and a separator. During the charge and discharge process of the battery, active ions are embedded and extracted back and forth between the positive electrode sheet and the negative electrode sheet. The electrolyte plays a role in conducting ions between the positive electrode sheet and the negative electrode sheet. The separator is disposed between the positive electrode sheet and the negative electrode sheet, mainly to prevent short circuit between the positive and negative electrodes, and at the same time allows ions to pass through.

[0083] The positive electrode sheet includes a positive electrode current collector and a positive electrode film layer provided on at least one surface of the positive electrode current collector.

[0084] As an example, the positive electrode current collector has two surfaces opposite to each other in its own thickness direction, and the positive electrode film layer is provided on any one or both of the two opposite surfaces of the positive electrode current collector.

[0085] In some embodiments, the positive electrode current collector can be a metal foil or a composite current collector. For example, as the metal foil, aluminum foil can be used. The composite current collector can include a polymer material substrate and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector can be formed by forming a metal material (such as aluminum, aluminum alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0086] In some embodiments, the positive electrode active material can be a positive electrode active material known in the art for lithium ion batteries. As an example, the positive electrode active material can include at least one of the following materials: lithium phosphate with an olivine structure, lithium transition metal oxides, and their respective modified compounds. However, the present application is not limited to these materials, and other conventional materials that can be used as the positive electrode active material of the battery can also be used. These positive electrode active materials can be used alone or in combination of two or more. Among them, examples of lithium transition metal oxides can include but are not limited to lithium cobalt oxide (such as LiCoO2), lithium nickel oxide (such as LiNiO2), lithium manganese oxide (such as LiMnO2, LiMn2O4), lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide (such as LiNi 1 / 3 Co 1 / 3 Mn 1 / 3O2 (which can also be abbreviated as NCM 333 )、LiNi 0.5 Co 0.2 Mn 0.3 O2 (which can also be abbreviated as NCM 523 )、LiNi 0.5 Co 0.25 Mn 0.25 O2 (which can also be abbreviated as NCM 211 )、LiNi 0.6 Co 0.2 Mn 0.2 O2 (which can also be abbreviated as NCM 622 )、LiNi 0.8 Co 0.1 Mn 0.1 O2 (which can also be abbreviated as NCM 811 )、lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2), and at least one of its modified compounds, etc. Examples of the lithium-containing phosphate with olivine structure may include, but are not limited to, lithium iron phosphate (such as LiFePO4 (which can also be abbreviated as LFP)), a composite material of lithium iron phosphate and carbon, lithium manganese phosphate (such as LiMnPO4), a composite material of lithium manganese phosphate and carbon, lithium manganese iron phosphate, and a composite material of lithium manganese iron phosphate and carbon.

[0087] In some embodiments, the positive electrode film layer further includes a binder. As an example, the binder may include at least one of polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, and fluorinated acrylate resin.

[0088] In some embodiments, the positive electrode film layer further includes a conductive agent. As an example, the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0089] In some embodiments, the positive electrode sheet can be prepared by the following method: dispersing the components for preparing the positive electrode sheet, such as the positive electrode active material, conductive agent, binder, and any other components, in a solvent (such as N-methylpyrrolidone) to form a positive electrode slurry; coating the positive electrode slurry on the positive electrode sheet structure, and after processes such as drying and cold pressing, the positive electrode sheet can be obtained.

[0090] The negative electrode sheet includes a positive electrode current collector and a negative electrode film layer provided on at least one surface of the positive electrode current collector, and the negative electrode film layer includes a negative electrode active material.

[0091] As an example, the negative electrode sheet structure includes a negative electrode current collector having two surfaces opposite to each other in its own thickness direction, and the negative electrode film layer is disposed on any one or both of the two opposite surfaces of the negative electrode current collector structure.

[0092] In some embodiments, the negative electrode current collector may be a metal foil or a composite current collector. For example, as the metal foil, copper foil can be used. The composite current collector may include a polymer material substrate layer and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector can be formed by forming a metal material (such as copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy, etc.) on a polymer material substrate (such as a substrate of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), polyethylene (PE), etc.).

[0093] In some embodiments, the negative electrode active material may be a negative electrode active material for a battery known in the art. As an example, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, and lithium titanate, etc. The silicon-based material may be selected from at least one of elemental silicon, silicon oxide compounds, silicon-carbon composites, silicon-nitrogen composites, and silicon alloys. The tin-based material may be selected from at least one of elemental tin, tin oxide compounds, and tin alloys. However, the present application is not limited to these materials, and other conventional materials that can be used as the negative electrode active material of the battery can also be used. These negative electrode active materials can be used alone or in combination of two or more.

[0094] In some embodiments, the negative electrode film layer further includes a binder. The binder may be selected from at least one of styrene-butadiene rubber (SBR), polyacrylic acid (PAA), sodium polyacrylate (PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), polymethacrylic acid (PMAA), and carboxymethyl chitosan (CMCS).

[0095] In some embodiments, the negative electrode film layer further includes a conductive agent. The conductive agent may be selected from at least one of superconducting carbon, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0096] In some embodiments, the negative electrode film layer further includes other additives, such as thickeners (such as sodium carboxymethyl cellulose (CMC-Na)), etc.

[0097] In some embodiments, the negative electrode sheet can be prepared in the following manner: the components for preparing the negative electrode sheet described above, such as the negative electrode active material, the conductive agent, the binder, and any other components, are dispersed in a solvent (such as deionized water) to form a negative electrode slurry; the negative electrode slurry is coated on the negative electrode sheet structure, and after processes such as drying and cold pressing, the negative electrode sheet can be obtained.

[0098] The electrolyte plays a role in conducting ions between the positive electrode sheet and the negative electrode sheet. There is no specific limitation on the type of the electrolyte in this application, and it can be selected according to requirements. For example, the electrolyte can be liquid, gel-like, or all-solid-state.

[0099] In some embodiments, the electrolyte uses an electrolytic solution. The electrolytic solution includes an electrolyte salt and a solvent.

[0100] In some embodiments, the electrolyte salt can be selected from at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorooxalate borate, lithium bis(oxalato)borate, lithium difluoro bis(oxalato)phosphate, and lithium tetrafluorooxalate phosphate.

[0101] In some embodiments, the solvent can be selected from at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl acetate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, methyl ethyl sulfone, and diethyl sulfone.

[0102] In some embodiments, the electrolytic solution may further optionally include additives. For example, the additives can include negative electrode film-forming additives, positive electrode film-forming additives, and can also include additives that can improve certain performance of the battery, such as additives for improving the overcharge performance of the battery, additives for improving the high-temperature or low-temperature performance of the battery, etc.

[0103] The electrolytic solution further includes the fluoroether prepared in the first aspect of this application.

[0104] In some embodiments, the secondary battery further includes a separator. There is no particular limitation on the type of the separator in this application, and any well-known porous structure separator with good chemical stability and mechanical stability can be selected.

[0105] In some embodiments, the material of the separator can be selected from at least one of glass fiber, non-woven fabric, polyethylene, polypropylene, and polyvinylidene fluoride. The separator can be a single-layer film or a multi-layer composite film, without particular limitation. When the separator is a multi-layer composite film, the materials of each layer can be the same or different, without particular limitation.

[0106] In some embodiments, the positive electrode sheet, the negative electrode sheet, and the separator may be made into an electrode assembly by a winding process or a stacking process.

[0107] In some embodiments, the secondary battery may include an outer package. The outer package may be used to encapsulate the above-mentioned electrode assembly and electrolyte.

[0108] In some embodiments, the outer package of the secondary battery may be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, etc. The outer package of the secondary battery may also be a soft package, such as a pouch soft package. The material of the soft package may be plastic. As plastics, polypropylene, polybutylene terephthalate, and polybutylene succinate, etc. may be cited.

[0109] The present application has no particular limitation on the shape of the secondary battery, and it may be cylindrical, square, or any other arbitrary shape. For example, Figure 1 is a secondary battery 5 with a square structure as an example.

[0110] In some embodiments, referring to Figure 2 , the outer package may include a housing 51 and a cover plate 53. Among them, the housing 51 may include a bottom plate and side plates connected to the bottom plate, and the bottom plate and the side plates enclose to form a receiving cavity. The housing 51 has an opening communicating with the receiving cavity, and the cover plate 53 can be covered on the opening to close the receiving cavity. The positive electrode sheet, the negative electrode sheet, and the separator may form an electrode assembly 52 through a winding process or a stacking process. The electrode assembly 52 is encapsulated in the receiving cavity. The electrolyte is infiltrated in the electrode assembly 52. The number of electrode assemblies 52 included in the secondary battery 5 may be one or more, and those skilled in the art can select according to specific actual needs.

[0111] In some embodiments, secondary batteries may be assembled into a battery module. The number of secondary batteries included in the battery module may be one or more, and the specific number can be selected by those skilled in the art according to the application and capacity of the battery module.

[0112] Figure 3 is a battery module 4 as an example. Referring to Figure 3 , in the battery module 4, multiple secondary batteries 5 may be arranged in sequence along the length direction of the battery module 4. Of course, they may also be arranged in any other arbitrary manner. Further, the multiple secondary batteries 5 may be fixed by fasteners.

[0113] Optionally, the battery module 4 may further include a housing having a receiving space, and multiple secondary batteries 5 are received in the receiving space.

[0114] In some embodiments, the above battery modules can also be assembled into a battery pack. The number of battery modules included in the battery pack can be one or more. Those skilled in the art can select the specific number according to the application and capacity of the battery pack.

[0115] Figure 4 and Figure 5 is Battery Pack 1 as an example. Referring to Figure 4 and Figure 5 In Battery Pack 1, a battery box and a plurality of battery modules 4 disposed in the battery box can be included. The battery box includes an upper box body 2 and a lower box body 3. The upper box body 2 can cover the lower box body 3 and form a closed space for accommodating the battery modules 4. The plurality of battery modules 4 can be arranged in the battery box in any manner.

[0116] Fourthly, an electrical device is proposed in an embodiment of the present application, including the battery of the third aspect of the present application.

[0117] In addition, the present application also provides an electrical device, which includes at least one of the secondary battery, battery module, or battery pack provided by the present application. The secondary battery, battery module, or battery pack can be used as the power source of the electrical device or as the energy storage unit of the electrical device. The electrical device can include mobile devices (such as mobile phones, laptops, etc.), electric vehicles (such as pure electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, electric bicycles, electric scooters, electric golf carts, electric trucks, etc.), electric trains, ships, satellites, energy storage systems, etc., but not limited thereto.

[0118] As the electrical device, the secondary battery, battery module, or battery pack can be selected according to its usage requirements.

[0119] Figure 6 is an electrical device as an example. The electrical device is a pure electric vehicle, a hybrid electric vehicle, or a plug-in hybrid electric vehicle, etc. In order to meet the high power and high energy density requirements of the electrical device for the secondary battery, a battery pack or a battery module can be adopted.

[0120] Another example of the device can be a mobile phone, a tablet computer, a laptop computer, etc. This device usually requires being thin and light, and a secondary battery can be used as the power source.

[0121] The technical solutions of the present invention will be further described in detail below with specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0122] In the present application, the intermediate product C can be generated by reacting at room temperature and pressure for 3 hours, and the fluoroether generation step can be generated by reacting at a temperature of 50°C and 0.8MPa for 5 hours, the product is centrifuged, washed with water, and then subjected to vacuum distillation to obtain the fluoroether. Among them, the other parameters of the preparation method of the fluoroether of Examples 1 to 27 and Comparative Examples 1 to 2 are according to the parameters in Table 1.

[0123]

[0124]

[0125] Performance Testing

[0126] The product purity and product yield of the fluoroethers prepared by the preparation methods of the fluoroethers in Examples 1 to 27 and Comparative Examples 1 to 3 were statistically analyzed, wherein the product purity was measured by gas chromatography, and the product yield = the actual amount of the target product generated / the theoretical amount of the target product generated × 100%, and the results are shown in Table 1. The fluoroether prepared in Example 1 was subjected to gas mass spectrometry detection, and the spectrum was as shown in Figure 7 shown.

[0127] As can be seen from Table 1, a mixture containing intermediate product C is generated by reacting an alkaline substance with compound A, and a fluoroether containing intermediate product C is obtained by reacting the mixture with difluoromethane and a catalyst to obtain fluorinated ethers with two fluorine atoms substituted at both ends. The raw materials of the present application are easy to obtain and the cost is low; the reaction conditions are mild, the process is simple, and the product yield is high. If the value of n is greater than 20, the reactivity of compound A will decrease, the reaction rate will be slow, and the yield of the mixture containing intermediate product C will be low.

[0128] Difluoromethane includes CHF2X, wherein X is selected from any one of chlorine, bromine and iodine. The alcoholic hydroxyl group can form an alcohol anion under alkaline conditions to attack the carbon positive center of the halogenated hydrocarbon, and the halogenated hydrocarbon removes the halogen to form an ether bond, which is more conducive to the replacement of alkali metal elements by fluorine atoms and improves the efficiency of the synthesis of double-terminal difluoro ethers.

[0129] When M is lithium, sodium, or potassium, the reaction rate with reactant A is good, which is beneficial for the reaction to move toward the direction of generating intermediate product C, and is beneficial for the generation of a mixture containing intermediate product C. Hydroxide-containing compound B can react with compound A to generate water, which is beneficial for generating a mixture containing intermediate product C after removing water, thereby improving the efficiency of the synthesis. Alkali metal-containing hydroxide compounds can further improve the synthesis efficiency of the mixture containing intermediate product C.

[0130] By using at least one of the organic solvents of benzene, toluene, xylene, acetonitrile and N,N-dimethylformamide, the water produced by the reaction of compound A and compound B can be removed. By utilizing the characteristics that the boiling point of the solvent is close to the boiling point of water and based on the characteristic that the solvent carries water, the synthesis efficiency of the mixture containing the intermediate product C can be improved.

[0131] In Comparative Example 1, since n is greater than 20, the reactivity of Compound A decreases, the reaction rate is slow, the yield of the mixture containing Intermediate C is low, and the yield of the fluoroether is low.

[0132] In Comparative Example 2, since no catalyst is added, the reaction efficiency is low and the yield of the fluoroether is low.

[0133] Figure 7 The gas-phase mass spectrum of the fluoroether prepared in Example 1 is shown in Table 2. The analysis results are as follows. In Table 2, the numerical values at the ion peak positions represent the mass-to-charge ratio. The results show that the product prepared in Example 1 is diethylene glycol bis(difluoromethyl) ether, and its structural formula is

[0134] F2CH-O-CH2-CH2-O-CH2-CH2-O-CHF2.

[0135] Table 2 Gas-phase mass spectrum of the fluoroether prepared in Example 1 Substance

[0136] Ion peak position Ion structural formula 45.1 <![CDATA[-CH2-O-CH2-]]> 51.0 <![CDATA[-CHF2]]> 77.1 <![CDATA[-C-O-CF2-]]> 95.1 <![CDATA[-CH2-CH2-O-CHF2]]> 125.1 <![CDATA[-CH2-O-CH2-CH2-O-CHF2]]> 138.0 <![CDATA[-CH-CH2-O-CH2-CH2-O-CHF2]]> 187.1 <![CDATA[-FCH-O-CH2-CH2-O-CH2-CH2-O-CHF2]]> 205.0 <![CDATA[-F2C-O-CH2-CH2-O-CH2-CH2-O-CHF2]]>

[0137] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the patent protection scope of the present invention.

Claims

1. A method for preparing a fluoroether, characterized in that, It includes the following steps: React compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate C; React the mixture containing intermediate C with difluoromethane under the catalysis of a catalyst to obtain a fluoroether; Wherein, compound A has the structural formula shown in (Ⅰ), intermediate C has the structural formula shown in (Ⅱ), and the fluoroether has the structural formula shown in (Ⅲ): n is a positive integer from 1 to 20; M includes at least one of lithium, sodium, and potassium.

2. The method for preparing a fluoroether according to claim 1, characterized in that, n is a positive integer from 2 to 8.

3. The method for preparing a fluoroether according to claim 1 or 2, characterized in that, The difluoromethane includes CHF2X, wherein X is selected from any one of chlorine, bromine, and iodine.

4. The method for preparing a fluoroether according to any one of claims 1 to 3, characterized in that, The basic substance B includes a compound containing a hydroxide group.

5. The method for preparing a fluoroether according to claim 4, characterized in that, The compound containing a hydroxide group includes a hydroxide compound of an alkali metal.

6. The method for preparing a fluoroether according to claim 5, characterized in that, The hydroxide compound of an alkali metal includes at least one of lithium hydroxide, sodium hydroxide, and potassium hydroxide.

7. The method for preparing a fluoroether according to any one of claims 1 to 6, characterized in that The organic solvent includes at least one of benzene, toluene, xylene, acetonitrile, N,N-dimethylformamide, n-hexane, and cyclohexane; and / or, The catalyst includes at least one of sodium iodide, magnesium iodide, potassium iodide, zinc iodide, sodium bromide, magnesium bromide, potassium bromide, and zinc bromide.

8. The method for preparing a fluoroether according to any one of claims 1 to 7, characterized in that In the step of reacting compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate C: the mass ratio of the organic solvent, basic substance B, and compound A is (1 to 20):(0.2 to 3):1; and / or, In the step of reacting the mixture containing intermediate C with difluoromethane under the catalysis of a catalyst to obtain a fluoroether: the mass ratio of difluoromethane, catalyst, and the mixture containing intermediate C is (0.1 to 4):(0.001 to 0.1):(2 to 22).

9. The preparation method of the fluoroether according to any one of claims 1 to 8, characterized in that, In the step of reacting compound A with basic substance B in an organic solvent to obtain a mixture containing intermediate C: The reaction temperature is -20 to 150 °C; and / or, The reaction time is 0.5 to 8 h.

10. The method for preparing a fluoroether according to any one of claims 1 to 9, characterized in that, In the step of reacting the mixture containing intermediate C with difluoromethane under the catalysis of a catalyst to obtain a fluoroether: The reaction temperature is 0 to 150 °C; and / or, The reaction time is 0.5 to 10 h; and / or, The reaction pressure is 0.1 to 5 MPa.

11. The method for preparing a fluoroether according to any one of claims 1 to 10, characterized in that, The step of reacting the mixture containing intermediate C with difluoromethane under the catalysis of a catalyst to obtain a fluoroether includes: React the mixture containing intermediate C with difluoromethane in an organic solvent in the presence of a catalyst, centrifuge the reaction product, and take the upper layer liquid, which is washed, dried, and rectified to obtain a fluoroether.

12. An electrolyte, characterized in that, It includes a fluoroether prepared by the method for preparing a fluoroether according to any one of claims 1 to 11.

13. A battery, characterized in that, It includes the electrolyte according to claim 12.

14. An electrical device, characterized in that, It includes the battery according to claim 13.

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