Method for synthesizing cells for single-ion batteries

Abstract

The present technology relates to a process for the synthesis of a lithium single ion monomer comprising simultaneously reacting a sulfonyl chloride compound with i) a fluorinated sulfonamide compound and ii) a compound suitable to act as a quenching base and a source of lithium cations. The simultaneous reaction of sulfonyl chloride with a fluorinated sulfonamide compound and a compound suitable to act as a quenching base and a source of lithium cations produces a single ion monomer.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims the rights and benefits of U.S. Provisional Application No. 63 / 350,119, filed on June 6, 2022, the contents of which are incorporated herein by reference. Technical Field

[0003] The present technology generally relates to methods for synthesizing lithium single-ion polymer electrolytes, and to methods for synthesizing lithium single-ion monomers. Background Art

[0004] Lithium batteries using lithium metal as negative electrodes have excellent energy density. However, with repeated cycles, such batteries may experience dendrite growth on the surface of the lithium metal electrode as lithium ions are unevenly re-plated on the surface of the lithium metal electrode when the battery is recharged. In order to minimize the effects of the morphological evolution (including dendrite growth) of the surface of the lithium metal anode, lithium metal batteries generally use a pressure system and a solid polymer electrolyte suitable for resisting the pressure applied thereto, as described in U.S. Patent No. 6,007,935 (which is incorporated herein by reference). However, after multiple cycles, the dendrites on the surface of the lithium metal anode may still grow through the solid polymer electrolyte and eventually cause a "soft" short circuit between the negative electrode and the positive electrode, resulting in a decline or poor performance of the battery. Therefore, the growth of dendrites may still degrade the cycle characteristics of the battery and constitute a major limitation to the optimization of the performance of lithium batteries with metallic lithium anodes.

[0005] Since the late 1970s, various types of solid polymer electrolytes suitable for use with lithium metal electrodes have been developed to overcome this problem, but they were found to lack conductivity and / or mechanical properties. However, single-ion conducting polymer electrolytes have emerged as promising candidates because the transference number of lithium cations approaches unity and thus prevents the formation of concentration gradients in the electrolyte and, therefore, dendrite formation.

[0006] The existing method for synthesizing lithium single ion monomers includes at least three steps (such as Figure 1 (shown in , and disclosed in ACS Appl. Mater. Interfaces 2016, 8, 10350-10359, incorporated herein by reference). A typical synthesis usually starts with a vinyl monomer (acrylate, methacrylate, styrene, etc.) with a sulfonate end group. The sulfonate is first converted to a sulfonyl chloride using thionyl chloride or oxalyl chloride. In the second step, trifluoromethanesulfonamide (NH2SO2CF3) is attached to generate a (trifluoromethylsulfonyl)imide (TFSI) anion. In this step, as Figure 1As shown in , triethylamine (TEA) is used as a base to quench the acidic protons on the byproduct HCl and TFSI anions, thereby generating nitrogen-based organic cations, or more specifically triethylammonium cations, on the intermediate monomer. Finally, in the third step, LiH is used to replace the triethylammonium cation with a lithium cation. The final product is then typically isolated by recrystallization (step not shown).

[0007] Other methods also include exchanging the triethylammonium cations obtained by the method disclosed above with potassium cations, and then exchanging the potassium cations for lithium cations in an additional step before or after crosslinking of the monomers (e.g., Polym. Chem., 2016, 7, 6901–6910; Journal of Polymer Science, 2020, 58, 2376-2388; and Electrochimica Acta, 2011, 57, 14-19, all incorporated herein by reference).

[0008] However, the above disclosed method has several disadvantages. Existing methods usually use LiH in the ion exchange step, which may be dangerous for large-scale processing. In addition, the triethylammonium intermediate obtained by these methods is a dark brown oil, which indicates that there are a large amount of impurities, which tend to remain in the recrystallized powder after reacting with LiH and recrystallization of the final product. In addition, the recrystallization of some monomers with ionic groups may cause self-polymerization, which prevents copolymerization with different monomers and limits the purposes and functions of such monomers. Specifically, self-polymerization is considered to be an uncontrollable reaction, wherein the final product is a mixture of very high molecular weight polymers and a small amount of monomers and oligomers. Therefore, in such a case, the control of the molecular weight of the final product is poor and affects the ionic conductivity of the final product.

[0009]

[0006] Therefore, there is a need for alternative or improved methods of synthesizing lithium single ion monomers that overcome or reduce at least some of the above-mentioned problems. Summary of the invention

[0010] Broadly speaking, the present technology relates to methods for synthesizing lithium single ion monomers.

[0011] According to one aspect, a method for synthesizing a lithium single ion monomer is provided, which comprises reacting a sulfonyl chloride compound with: i) a fluorinated sulfonamide compound; and ii) a compound suitable for acting as a quenching base and a source of lithium cations. The simultaneous reaction of the sulfonyl chloride with the fluorinated sulfonamide compound and the compound suitable for acting as a quenching base and a source of lithium cations produces a single ion monomer.

[0012] According to another aspect, the present technology provides a method for synthesizing a lithium single ion monomer, the method comprising reacting a sulfonyl chloride compound with: i) a fluorinated sulfonamide compound; and ii) a compound suitable for serving as a quenching base and a source of lithium cations; wherein the simultaneous reaction of the sulfonyl chloride with the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a source of lithium cations produces a single ion monomer; wherein the sulfonyl chloride compound has the formula:

[0013]

[0014] wherein: R1 and R2 are each independently H or F; R3 is H, F, CN or CH3; R4 is an ester group, a phenyl group having L1 substituted at the ortho, para or meta position, a fully or partially fluorinated phenyl group having L1 substituted at the ortho, para or meta position, an amide group, a carbonate group or an ether group; and L1 is an n-alkyl group (e.g., n=1 to 16), a fluorinated alkyl group (e.g., C1 to C 16 ), branched alkyl (e.g., C3 to C 16 ), oxyethylene linking groups (e.g., C4 to C 16 ), fluorinated oxyethylene linking groups (e.g., C4 to C 16 ), cycloalkyl (e.g., C4 to C7), fluorinated cycloalkyl (e.g., C4 to C7), or L1 is absent. According to another aspect, a method for synthesizing a lithium single ion monomer is provided, comprising: 1) obtaining a sulfonyl chloride compound from a sulfonate ester / salt; 2) reacting the sulfonyl chloride compound with the following simultaneously to obtain an unpurified lithium single ion monomer: i) a fluorinated sulfonamide; and ii) a compound suitable for serving as a quenching base and a lithium cation source; and 3) purifying the unpurified lithium single ion monomer.

[0015] According to another aspect, the methods of the present technology are performed at reduced cost and with high atom economy (ie, less waste of reactants) compared to existing methods because they include one step and bypass the synthesis of triethylammonium intermediates.

[0016] According to another aspect, methods of practicing the present technology are safer than existing methods because the bases used in the synthesis are safer to handle in scaled-up production.

[0017] According to another aspect, the methods of the present technology produce a final product that is substantially free of impurities.

[0018] According to another aspect, the method of the present technology overcomes the self-polymerization of lithium single-ion monomers. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Reference will now be made to the drawings.

[0020] Figure 1A typical three-step synthesis of lithium single-ion monomers according to Procarreli et al., ACS Appl. Mater. Interfaces 2016, 8, 10350-10359 (incorporated herein by reference) is shown. DETAILED DESCRIPTION

[0021] definition

[0022] As used herein, "including," "comprising," or "having," "containing," "involving," and variations thereof, are meant to encompass the items listed thereafter as well as optional additional items.

[0023] It must be noted that, as used in this specification and the appended claims, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise.

[0024] As used herein, the term "and / or" should be taken as specifically disclosing each of the two specific features or components with or without the other. For example, "A and / or B" should be taken as specifically disclosing each of (i) A, (ii) B, and (iii) A and B, just as if each were individually listed herein.

[0025] As used herein, the term "about" in the context of a given value or range refers to a value or range that is within 20%, preferably within 10%, and more preferably within 5% of the given value or range.

[0026] As used herein, the term "substantially" means to a great or significant extent.

[0027] As used herein, the expression "electron withdrawing group" refers to an atom or group that attracts electron density from neighboring atoms toward itself, usually through resonance or inductive effects.

[0028] The present disclosure is not limited in its application to the arrangement of the construction details and parts set forth in the following description or illustrated in the accompanying drawings. The present disclosure can have other embodiments and can be practiced or implemented in a variety of ways. In addition, the wording and terminology used herein are for descriptive purposes and should not be considered restrictive.

[0029] In general, the present technology provides methods for synthesizing lithium single-ion monomers that are simpler, safer, less costly, and more efficient than existing methods for synthesizing lithium single-ion monomers.

[0030] In certain embodiments, methods of the present technology include simultaneously reacting a sulfonyl chloride compound with i) a fluorinated sulfonamide compound and ii) a compound suitable for acting as a quenching base and as a source of lithium cations.

[0031] In some embodiments, the sulfonyl chloride compound has the formula:

[0032]

[0033] wherein: R1 and R2 are each independently H or F; R3 is H, F, CN or CH3; R4 is an ester group, a phenyl group having L1 substituted at the ortho, para or meta position, a fully or partially fluorinated phenyl group having L1 substituted at the ortho, para or meta position, an amide group, a carbonate group or an ether group; and L1 is an n-alkyl group (e.g., n=1 to 16), a fluorinated alkyl group (e.g., C1 to C 16 ), branched alkyl (e.g., C3 to C 16 ), oxyethylene linking groups (e.g., C4 to C 16 ), fluorinated oxyethylene linking groups (e.g., C4 to C 16 ), cycloalkyl (e.g., C4 to C7), fluorinated cycloalkyl (e.g., C4 to C7), or L1 is absent.

[0034] In some cases, an ester group is -(C=O)-O- or -O-(C=O)-). In some cases, an amide group is -(C=O)-NH-. In some cases, a carbonate group is (-O-(C=O)-O-). In some cases, an ether group is (-O-).

[0035] In some embodiments, the fluorinated sulfonamide compound has the formula R A -SO2-NH2, where R A Selected from -F, -CF3, -CF2CF3, -(CF2) n CF3, -C6F5, branched C3 to C4 fluoroalkyl (e.g., -CF-(CF3)2, -CF(CF3)-CF2-CF3 and CF2-CF-(CF3)2), linear perfluoroethyl ether (e.g., -(CF2CF2O) n -CF2CF3 wherein n=1, 2 or 3) and an aromatic compound substituted with at least one fluorine and at least one electron withdrawing group.

[0036] In some embodiments, the electron withdrawing group is selected from -CN, -NO2, -CF3, and -SO2CF3.

[0037] In other embodiments, the aromatic compound is -C6F4-CF3 or -C6F4-SO2CF3, as disclosed in Huang et al. Chem. Mater. 2019, 31, 18, 7558 (incorporated herein by reference).

[0038] In the methods of the present technology, the simultaneous reaction of a sulfonyl chloride with a fluorinated sulfonamide compound and a compound suitable for acting as a quenching base and as a source of lithium cations produces lithium single ion monomers in a single step.

[0039] In some embodiments, the method of the present technology is a "one-pot synthesis". As used herein, the expression "one-pot synthesis" refers to the method of the present technology being performed in sequential chemical reactions in only one reactor. The method of the present technology being performed in one reactor allows for the avoidance of lengthy separation processes and purification of intermediate chemical compounds, and can increase chemical yields.

[0040] In certain embodiments, as will be shown below, the fluorinated sulfonamide compound is trifluoromethanesulfonamide.

[0041] To date, TEA has become the base of choice when synthesizing lithium single-ion monomers because weaker bases such as pyridine were found to fail to generate the target compound, while stronger bases such as NaH and EtONa produced side reactions and strongly colored and insoluble products (Shaplov et al., Polym. Chem., 2011, 2, 2609-2618, incorporated herein by reference). In addition, generating the triethylamine counterion in an intermediate step is a preferred route for the synthesis because its removal can be achieved during recrystallization and purification of the final product by 1 H NMR is easily monitored.

[0042] However, the method of the present technology does not use TEA when synthesizing lithium single-ion monomers. Therefore, in certain embodiments, the method of the present technology does not require the synthesis of nitrogen-based organic cations. In other embodiments, the method of the present technology does not require the synthesis of stable nitrogen-based organic cations. In some embodiments, the nitrogen-based organic cation is a triethylammonium intermediate; therefore, the method of the present technology does not require the synthesis of triethylammonium intermediates. In other embodiments, the nitrogen-based organic cation is a stable triethylammonium intermediate; therefore, the method of the present technology does not require the synthesis of stable triethylammonium intermediates. In yet other embodiments, the nitrogen-based organic cation can be an alkylammonium such as R5R6R7R8N + , wherein R5, R6, R7 and R8 are independently selected from H, C1 to C6 linear alkyl and C3 to C6 branched alkyl. R5, R6, R7 and R8 may be the same or different. In some further embodiments, the nitrogen-based organic cation may be a substituted or unsubstituted imidazole Pyridine Piperidine and benzimidazole The substituents may be independently selected from H, C1 to C6 linear alkyl and C3 to C6 branched alkyl; and may be the same or different. In some further embodiments, the nitrogen-based organic cation may be 1,2,3-triazole or 1,2,4-triazole Therefore, in certain embodiments, the methods of the present technology do not require the synthesis of alkylammonium, imidazole Pyridine Piperidine Benzimidazole 1,2,3-Triazole and 1,2,4-triazole Advantageously, because the synthesis of nitrogen-based organic cations is bypassed, the methods of the present technology provide a cheaper method for synthesizing lithium single-ion monomers and produce less reactant waste than existing methods.

[0043] In certain embodiments, the compound suitable for acting as a quenching base and a lithium cation source is a lithium-containing alkaline compound. In some embodiments, the lithium-containing alkaline compound may be selected from Li2CO3, LiOH, Li2SO3, Li3PO4, lithium acetate and lithium formate and combinations thereof. In one embodiment, the lithium-containing alkaline compound is LiOH. Traditionally, due to the possible hydrolysis of LiOH to esters in acrylates and methacrylates, bases such as LiOH are avoided, especially when synthesizing monomers derived from acrylates and methacrylates. However, without being bound by theory, researchers of the present technology have found that under the anhydrous reaction conditions and short reaction times required by the method of the present technology, LiOH hydrolyzes acrylates insignificantly. This is believed to be partly due to the relatively neutral pH in the reaction, where LiOH is neutralized by HCl byproducts before it may begin to hydrolyze the acrylate. In addition, compared with existing methods, the use of LiOH in the method of the present technology provides a safer method for synthesizing lithium monoion monomers, because LiOH is safe for large-scale processing and is particularly suitable for the expanded production of lithium monoion monomers.

[0044] In certain embodiments, before adding the sulfonyl chloride compound, the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a lithium cation source are dissolved in an anhydrous solvent and mixed together. In some embodiments, the anhydrous solvent can be selected from anhydrous methyl cyanide (MeCN), tetrahydrofuran (THF), acetone, dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). It is believed that aqueous solvents such as water, alcohol and amine-containing solvents are not suitable for the method of the present technology, because water and hydroxyl can react with sulfonyl chloride to produce sulfonic acid, which is not a desired product. Therefore, in certain embodiments, the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a lithium cation source are not dissolved in an aqueous solvent.

[0045] In certain embodiments, the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a source of lithium cations are mixed together at a temperature of about 15° C. to about 30° C. In other embodiments, the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a source of lithium cations are mixed together at a temperature of about 15° C., about 20° C., about 25° C. (i.e., room temperature (RT)), or about 30° C. In some embodiments, the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a source of lithium cations are mixed together at a temperature of about 25° C. (RT).

[0046] In other embodiments, the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a source of lithium cations are mixed together for about 30 minutes to about 2 hours. In other embodiments, the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a source of lithium cations are mixed together for about 30 minutes, about 45 minutes, about 1 hour, about 1.5 hours, or about 2 hours. In some embodiments, the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a source of lithium cations are mixed together for about 1 hour.

[0047] In certain embodiments, the mixture of the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a source of lithium cations is cooled to a temperature of about -5°C to about +4°C prior to adding the sulfonyl chloride compound.

[0048] In some embodiments, the mixture of the fluorinated sulfonamide compound and the compound suitable for serving as the quenching base and the source of lithium cations is cooled to a temperature of about 0° C. The temperature of the mixture can be cooled to about −5° C. to about +4° C., or to about 0° C. using known techniques such as an ice water bath or the like.

[0049] In some embodiments, the sulfonyl chloride compound can also be dissolved in an anhydrous solvent, which is then added to a mixture of a fluorinated sulfonamide compound and a compound suitable for serving as a quenching base and a lithium cation source. In certain embodiments, the anhydrous solvent is identical to the anhydrous solvent for dissolving the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a lithium cation source. In other embodiments, the anhydrous solvent for dissolving sulfonyl chloride is different from the anhydrous solvent for dissolving the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a lithium cation source. In such an embodiment, two different solvents are miscible with each other. In some embodiments, the sulfonyl chloride compound is dissolved in an anhydrous solvent selected from anhydrous MeCN, THF, acetone, DMF and DMSO. For the same reasons provided above, the sulfonyl chloride compound is not dissolved in an aqueous solvent.

[0050] In certain embodiments, a mixture of sulfonyl chloride and anhydrous solvent is added slowly and / or in a dropwise manner to a mixture of a fluorinated sulfonamide compound and a compound suitable for serving as a quenching base and a source of lithium cations. This prevents temperature jumps and solvent evaporation, and allows the HCl byproduct to be effectively quenched by the quenching base.

[0051] However, the methods of the present technology are not limited to a specific order of adding reagents. Therefore, in other embodiments, a mixture of a fluorinated sulfonamide compound dissolved in an anhydrous solvent and a compound suitable for acting as a quenching base and a source of lithium cations can be added to a sulfonyl chloride compound previously dissolved in an anhydrous solvent.

[0052] In other embodiments, the reaction of sulfonyl chloride with fluorinated sulfonamide and a compound suitable for acting as a quenching base and a source of lithium cations is carried out at a starting temperature of about -5 ° C and is increased to about +30 ° C. In some embodiments, the reaction is carried out at a starting temperature of about 0 ° C and is increased to about 25 ° C. In other embodiments, the reaction is carried out for about 30 minutes to about 5 hours. In other embodiments, the reaction is carried out for about 30 minutes to about 1 hour, about 30 minutes to about 1.5 hours, about 1.5 hours to about 3.5 hours, about 2 hours to about 3 hours, or about 2 hours to about 4 hours. In some embodiments, the reaction is carried out for about 2.5 hours. In another embodiment, the reaction is carried out for about 3 hours. In yet another embodiment, the reaction is carried out for about 30 minutes. In other embodiments, the reaction is carried out at a starting temperature of about 0 ° C and is increased to about 25 ° C for about 2.5 hours. In other embodiments, the reaction is carried out at a starting temperature of about 0 ° C and is increased to about 25 ° C for about 3 hours. In yet other embodiments, the reaction is conducted at a starting temperature of about 0°C and increased to about 25°C for about 30 minutes.

[0053] In some embodiments, the sulfonyl chloride compound has the formula:

[0054]

[0055] wherein R1 and R2 are each independently H or F; R3 is H, F, CN or CH3; R4 is an ester group, a phenyl group having L1 substituted at the ortho, para or meta position, a fully or partially fluorinated phenyl group having L1 substituted at the ortho, para or meta position, an amide group, a carbonate group or an ether group; L1 is an n-alkyl group (e.g., n=1 to 16), a fluorinated alkyl group (e.g., C1 to C 16 ), branched alkyl (e.g., C3 to C 16 ), oxyethylene linking groups (e.g., C4 to C 16 ), fluorinated oxyethylene linking groups (e.g., C4 to C 16), cycloalkyl (e.g., C4 to C7), fluorinated cycloalkyl (e.g., C4 to C7), or L1 is absent.

[0056] In some cases, an ester group is -(C=O)-O- or -O-(C=O)-). In some cases, an amide group is -(C=O)-NH-. In some cases, a carbonate group is (-O-(C=O)-O-). In some cases, an ether group is (-O-).

[0057] In certain embodiments, the sulfonyl chloride compound is converted from a sulfonate ester.

[0058] In certain embodiments, the sulfonate comprises a vinyl monomer, such as acrylate, methacrylate, styrene, or vinyl acetate. In other embodiments, the sulfonate has the formula:

[0059]

[0060] Wherein R is H or CH3.

[0061] In certain embodiments, the cation associated with the sulfonate group may be selected from H + , K + 、Na + , Li + , Rb + and Cs + of monovalent cations.

[0062] In certain embodiments, the sulfonyl chloride has the formula:

[0063]

[0064] Wherein R is H or CH3.

[0065] In some embodiments, the conversion of sulfonate / salt to sulfonyl chloride is carried out using one or more of thionyl chloride and oxalyl chloride. In certain embodiments, the conversion is carried out at a starting temperature of about -5 ° C and is increased to about + 30 ° C. In some embodiments, the conversion is carried out at a starting temperature of about 0 ° C and is increased to about 25 ° C. In other embodiments, the conversion is carried out for about 12 hours to about 36 hours. In some other embodiments, the conversion is carried out for about 14 hours to about 18 hours, about 20 hours to about 26 hours. In some embodiments, the conversion is carried out for about 16 hours. In other embodiments, the conversion is carried out for about 24 hours. In other embodiments, the conversion is carried out at a starting temperature of about 0 ° C and is increased to about 25 ° C for about 16 hours. In some other embodiments, the conversion is carried out at a starting temperature of about 0 ° C and is increased to about 25 ° C for about 24 hours.

[0066] In certain embodiments, the method of the present technology further comprises the step of purifying the lithium single ion monomer. In certain implementations of these embodiments, the step of purifying the lithium single ion monomer comprises purifying by silica gel flash chromatography or by recrystallization.

[0067] In some embodiments, the lithium monoion monomer is purified by silica gel flash chromatography. In some embodiments of these embodiments, the step of purification also includes leaving residual solvent with the monomer to reduce the concentration of the monomer in the final product. Advantageously, the purification by silica gel flash chromatography prevents the self-polymerization of the monoion monomer, and further alleviates the self-polymerization by leaving the residual solvent in the final product. In addition, the purification by silica gel flash chromatography allows the removal of colored impurities. Therefore, the final lithium monoion monomer obtained by the method of the present technology is an almost transparent viscous oil (with residual solvent).

[0068] In other embodiments, an inhibitor to prevent self-polymerization can be used in the step of purifying the lithium single ion monomer. In certain embodiments, the inhibitor can be added to the column elution fraction containing the pure product during silica gel flash chromatography. In such an embodiment, the elution solvent can be removed by a rotary evaporator, thereby fully mixing the monomer with the inhibitor.

[0069] Inhibitors suitable for the methods of the present technology include 4-methoxyphenol (also known as MEHQ) and butylated hydroxytoluene (BHT). In some embodiments, the inhibitor can be used at ppm levels, including about 100 ppm to about 500 ppm. In some embodiments, about 3 mg to about 5 mg of MEHQ can be added to about 20 g of product to prevent self-polymerization.

[0070] In other embodiments, the step of purifying the lithium single ion monomer comprises removing the LiCl byproduct prior to purification by silica gel flash chromatography. In certain implementations of these embodiments, the step of removing LiCl comprises filtering the reaction product prior to running silica gel flash chromatography.

[0071] In other embodiments, the method of the present technology also includes polymerizing the lithium single ion monomer to obtain a lithium single ion polymer. In certain embodiments, the polymerization can be carried out by controlled polymerization (ATRP (Atom Transfer Radical Polymerization, "atom transfer radical polymerization"), RAFT (Reversible Addition Fragmentation Chain Transfer, "reversible addition fragmentation chain transfer"), anionic polymerization, cationic polymerization, free radical polymerization or NMP (Nitroxide-Mediated Radical Polymerization, "nitrogen oxide mediated free radical polymerization")). In the method of the present technology, the polymerization of the final lithium single ion monomer produces a white powder without colored impurities.

[0072] In certain embodiments, the methods of the present technology include the following steps:

[0073]

[0074] Wherein R is H or CH3.

[0075] In such an embodiment, the lithium single ion monomer obtained has the following formula:

[0076]

[0077] wherein R1 and R2 are independently H or F; R3 is H, F, CN or CH3; R4 is an ester group, a phenyl group having L1 substituted at the ortho, para or meta position, a fully or partially fluorinated phenyl group having L1 substituted at the ortho, para or meta position, an amide group, a carbonate group or an ether group; L1 is an n-alkyl group (e.g., n=1 to 16), a fluorinated alkyl group (e.g., C1 to C 16 ), branched alkyl (e.g., C3 to C 16 ), oxyethylene linking groups (e.g., C4 to C 16 ), fluorinated oxyethylene linking groups (e.g., C4 to C 16 ), cycloalkyl (e.g., C4 to C7), fluorinated cycloalkyl (e.g., C4 to C7), or L1 is absent; R f Selected from F, CF3, CF2CF3, (CF2) n CF3, C6F5, branched C3 to C4 fluoroalkyl, -(CF2CF2O) n -CF2CF3 wherein n=1, 2 or 3 and an aromatic group substituted with at least one fluorine and at least one electron withdrawing group; and the electron withdrawing group is selected from -CN, -NO2, -CF3 and -SO2CF3; and M is a monovalent cation H + , Li+ 、Na + , K + , Rb + or Cs + .

[0078] In some cases, an ester group is -(C=O)-O- or -O-(C=O)-). In some cases, an amide group is -(C=O)-NH-. In some cases, a carbonate group is (-O-(C=O)-O-). In some cases, an ether group is (-O-).

[0079] In other embodiments, as described above, the method of the present technology includes: 1) obtaining a sulfonyl chloride compound from a sulfonate ester / salt; 2) reacting the sulfonyl chloride compound with the following to obtain an unpurified lithium single ion monomer: i) a fluorinated sulfonamide compound; and ii) a compound suitable for serving as a quenching base and a lithium cation source; and 3) purifying the unpurified lithium single ion monomer. In certain embodiments, the fluorinated sulfonamide compound has a formula R A -SO2-NH2, where R A Selected from -F, -CF3, -CF2CF3, -(CF2) n CF3, -C6F5, branched C3 to C4 fluoroalkyl (e.g., -CF-(CF3)2, -CF(CF3)-CF2-CF3 and CF2-CF-(CF3)2), linear perfluoroethyl ether (e.g., -(CF2CF2O) n -CF2CF3 wherein n=1, 2 or 3) and an aryl compound substituted with at least one fluorine and at least one electron withdrawing group. In some embodiments, the electron withdrawing group is selected from -CN, -NO2, -CF3 and -SO2CF3. In other embodiments, the aryl compound is -C6F4-CF3 or -C6F4-SO2CF3.

[0080] In certain embodiments, the mass yield of lithium single ion monomers obtained by the methods of the present technology is about 60% to about 99%, about 70% to about 80%, about 80% to 99%, about 75%, or about 95%.

[0081] Example

[0082] The following examples are given to illustrate the practice of various embodiments of the present disclosure. They are not intended to limit or define the entire scope of the present disclosure.

[0083] It should be understood that the subject matter of the present disclosure is not limited to the particular embodiments described and illustrated herein, but encompasses all modifications and variations coming within the scope of the subject matter of the present disclosure as defined in the appended claims.

[0084] Example 1: Lithium 1-[3-(acryloyloxy)-propylsulfonyl]-1-(trifluoromethylsulfonyl)imide

[0085] Synthesis of (LiATFSI)

[0086] In the 500mL round-bottomed flask equipped with a magnetic stirring bar filled with Ar, anhydrous DMF (2.8g, 0.038mol) is dissolved in 50mL anhydrous MeCN. With ice-water bath, the flask is cooled to 0 ℃, and under stirring, oxalyl chloride (20.8g, 0.164mol) is added dropwise via a syringe. 20mL anhydrous MeCN is added afterwards to dilute the solution and remove the ice bath so that the reaction is stirred at room temperature for 1 hour. After there is no bubble formation, the reaction is cooled to 0 ℃ again. 3-sulfopropyl acrylate potassium salt (30g, 0.129mol) is suspended in 75mL MeCN, and under Ar stream and vigorous stirring, is added via funnel in portions. Other 25mlMeCN is used to wash away residual solids from a weighing container and to be added to the reaction flask. The mixture is stirred at room temperature for 16 hours. Then in a separating funnel, the reaction is poured into 200mL ice-cold deionized water. The bottom aqueous layer is collected and washed three times with 50mL dichloromethane (DCM). The top organic layer is collected and merged with 150mL DCM solution. The organic solution is further washed three times with 50mL deionized (DI) water and dried with anhydrous MgSO. Then it is filtered, and the clear filtrate is reduced to a slightly yellow liquid via a rotary evaporator. 5mg MEHQ inhibitor is added to thick 3-(chlorosulfonyl)propyl acrylate (J501, as shown in the following synthetic route) and stored at 4°C for further use.

[0087] To synthesize lithium LiATFSI (J503), lithium hydroxide (1.3 g, 54 mmol) and trifluoromethanesulfonylamide (4.0 g, 27 mmol) were dissolved in 25 mL of anhydrous MeCN in an Ar-filled flask equipped with a magnetic stir bar. The mixture was stirred at room temperature for 1 hour and then cooled to 0°C using an ice-water bath. 3-(Chlorosulfonyl)propyl acrylate (5.7 g, 27 mmol) was then dissolved in 12 mL of anhydrous MeCN and the solution was added dropwise to the reaction flask. The mixture was then stirred from 0°C to room temperature for 2.5 hours. After the reaction, the white precipitate (LiCl salt) was filtered off, and the filtrate was reduced and purified by a silica gel column. LiATFSI was eluted from pure DCM to DCM + 20 vol% THF. The product fractions were combined and 4 mg of MEHQ inhibitor was added. The solvent was reduced to about 50 wt% compared to LiATFSI, and the viscous solution was stored at 4°C for further use. By 1The residual solvent content and monomer purity were quantified by H NMR integration. The final product contained 6.6 g LiATFSI and 3.4 g residual solvent (DCM+THF). The reaction yield was 74%.

[0088] The synthetic route for preparing LiATFSI according to this embodiment is shown below.

[0089]

[0090] Example 2: Synthesis of lithium 1-[3-(methacryloyloxy)-propylsulfonyl]-1-(trifluoromethylsulfonyl)imide (LiMTFSI)

[0091] Under the continuous flow Ar stream, add 70mL anhydrous MeCN and 18.57g (0.146mol) oxalyl chloride in the 250mL three-necked flask equipped with a gas inlet adapter. The mixture is cooled with an ice bath and 2mL DMF is added dropwise via a syringe while stirring. After interpolation, the ice bath is removed and the mixture is stirred at room temperature for 1 hour. After this, 3-sulfopropyl methacrylate potassium salt (22.7g, 0.09mol) is slowly added to the above-mentioned mixture with an ice bath cooling reaction mixture again. The reaction mixture is slowly warmed to room temperature and stirred for 24 hours. The reaction mixture is then filtered to remove KCl and concentrated by a rotary evaporator filtrate. The residual liquid is diluted by 50mL DCM and by 50mL DI water washing DCM solution. Wash water with 30mL DCM three times. Merge organic phase and use anhydrous MgSO4 dry. After filtration, the filtrate was concentrated and purified by flash column chromatography with DCM as eluting solvent to obtain 3-(chlorosulfonyl)propyl methacrylate (J509, as shown in the following synthesis route) (14.5 g, 71%) as a light yellow liquid. In order to synthesize LiMTFSI (J505, as shown in the following synthesis route), 2.95 g of lithium hydroxide (0.12 mol) and 8.9 g of trifluoromethanesulfonamide (59 mmol) were added to a 250 mL three-necked flask equipped with an additional funnel and a gas inlet adapter under an Ar atmosphere, and 40 mL of anhydrous THF was then added. The mixture was cooled to 0 ° C by an ice bath. A mixture of J509 (13.54 g, 59 mmol) and 40 mL of anhydrous THF was then added dropwise to the reaction solution. The reaction mixture was then slowly warmed to room temperature for 3 hours under stirring. After the reaction, the solution was concentrated in vacuo and then diluted by DCM. The white solid was removed by filtration and the solvent was evaporated by a rotary evaporator to obtain J505 as a light yellow liquid containing 19.6 g of LiMTFSI. The reaction yield was 95%.

[0092] A synthetic route for preparing LiMTFSI according to this embodiment is shown below.

[0093]

[0094] Those skilled in the art will appreciate variations and modifications after reading this disclosure. The disclosed features may be implemented in any combination and sub-combination (including multiple dependent combinations and sub-combinations) with one or more other features described herein. The various features described or illustrated above, including any of their constituent elements, may be combined or integrated in other systems. In addition, certain features may be omitted or not implemented. Examples of variations, substitutions, and alterations are determinable by those skilled in the art and may be performed without departing from the scope of information disclosed herein.

[0095] It should be understood that the present technology is not limited to the particular embodiments described and illustrated herein, but encompasses all modifications and variations coming within the scope of the present technology as defined in the appended claims.

[0096] All references cited in this specification and their references are incorporated herein by reference in their entirety to the extent applicable for teachings of additional or alternative details, features and / or technical background.

Claims

1. A method for synthesizing a lithium single ion monomer, the method comprising reacting a sulfonyl chloride compound with: i) fluorinated sulfonamide compounds; and ii) a compound suitable for acting as a quenching base and a source of lithium cations; wherein the simultaneous reaction of a sulfonyl chloride with the fluorinated sulfonamide compound and the compound suitable for serving as a quenching base and a source of lithium cations produces the single ion monomer; wherein the sulfonyl chloride compound has the formula: in R1 and R2 are each independently H or F; R3 is H, F, CN or CH3; R4 is an ester group, a phenyl group having L1 substituted at the ortho, para or meta position, a fully or partially fluorinated phenyl group having L1 substituted at the ortho, para or meta position, an amide group, a carbonate group or an ether group; and L1 is n-alkyl, fluorinated alkyl, branched alkyl, oxyethylene linking group, fluorinated oxyethylene linking group, cycloalkyl, fluorinated cycloalkyl, or L1 is absent.

2. The method according to claim 1, wherein the fluorinated sulfonamide compound has the formula R A -SO2-NH2, where R A Selected from F, CF3, CF2CF3, (CF2)nCF3, C6F5, branched C3 to C4 fluoroalkyl, -(CF2CF2O) n -CF2CF3 wherein n=1, 2 or 3 and an aryl group substituted with at least one fluorine and at least one electron withdrawing group.

3. The method of claim 2, wherein the electron withdrawing group is selected from -CN, -NO2, -CF3 and -SO2CF3.

4. The method according to any one of claims 1 to 3, wherein the method does not require the synthesis of nitrogen-based organic cations.

5. The method according to any one of claims 1 to 4, wherein the method does not require the synthesis of stable nitrogen-based organic cations.

6. The method according to any one of claims 1 to 5, wherein the compound suitable for acting as a quenching base and a source of lithium cations is a lithium-containing basic compound.

7. The method according to claim 6, wherein the lithium-containing alkaline compound is selected from the group consisting of Li2CO3, LiOH, Li2SO3, Li3PO4, lithium acetate and lithium formate, and combinations thereof.

8. The method according to any one of claims 1 to 7, wherein the sulfonate compound has the formula: in R1 and R2 are each independently H or F; R3 is H, F, CN or CH3; R4 is an ester group, a phenyl group having L1 substituted at the ortho, para or meta position, a fully or partially fluorinated phenyl group having L1 substituted at the ortho, para or meta position, an amide group, a carbonate group or an ether group; L1 is n-alkyl, fluorinated alkyl, branched alkyl, oxyethylene linking group, fluorinated oxyethylene linking group, cycloalkyl, fluorinated cycloalkyl, or L1 is absent; and M is a monovalent cation H + , Li + 、Na + , K + , Rb + or Cs + .

9. The process of claim 8, wherein the conversion of the sulfonate to the sulfonyl chloride is carried out using one or more of thionyl chloride and oxalyl chloride.

10. The method according to any one of claims 1 to 9, wherein the sulfonyl chloride compound has the following formula: Where R is H or CH3, 11. The method according to any one of claims 8 to 10, wherein the sulfonate group has the following formula: Wherein R is H or CH3.

12. The method according to any one of claims 1 to 11, wherein the lithium single ion monomer has the following formula: in R1 and R2 are independently H or F; R3 is H, F, CN or CH3; R4 is an ester group, a phenyl group having L1 substituted at the ortho, para or meta position, a fully or partially fluorinated phenyl group having L1 substituted at the ortho, para or meta position, an amide group, a carbonate group or an ether group; L1 can be n-alkyl, fluorinated alkyl, branched alkyl, ethylene oxide linking group, fluorinated ethylene oxide linking group, cycloalkyl, fluorinated cycloalkyl, or L1 is absent; R f Selected from F, CF3, CF2CF3, (CF2) n CF3, C6F5, branched C3 to C4 fluoroalkyl, -(CF2CF2O) n -CF2CF3 wherein n=1, 2 or 3 and aryl substituted with at least one fluorine and at least one electron withdrawing group; and the electron withdrawing group is selected from -CN, -NO2, -CF3 and -SO2CF3; and M is a monovalent cation H + , Li + 、Na + , K + , Rb + or Cs + .

13. The method according to any one of claims 1 to 12, further comprising a purification step of the lithium single-ion monomer.

14. The method of claim 13, wherein the purification step comprises removing the LiCl byproduct and running silica gel flash chromatography.

15. The method of claim 13 or 14, further comprising polymerizing the lithium single ion monomer.

16. The method according to any one of claims 1 to 15, wherein the method comprises the following steps: Wherein R is H or CH3.

17. A method for synthesizing a lithium single ion monomer, the method comprising: 1) Obtaining a sulfonyl chloride compound from a sulfonate ester / salt; 2) reacting the sulfonyl chloride compound with the following simultaneously to obtain an unpurified lithium single ion monomer: i) a fluorinated sulfonamide compound, and ii) a compound suitable for acting as a quenching base and a source of lithium cations; and 3) Purifying the unpurified lithium single-ion monomer.

18. The method of claim 17, wherein the fluorinated sulfonamide compound has the formula R A -SO2-NH2, where R A Selected from F, CF3, CF2CF3, (CF2) n CF3, C6F5, branched C3 to C4 fluoroalkyl, -(CF2CF2O) n -CF2CF3 wherein n=1, 2 or 3 and an aryl group substituted with at least one fluorine and at least one electron withdrawing group.

19. The method of claim 18, wherein the electron withdrawing group is selected from -CN, -NO2, -CF3 and -SO2CF3.

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