A process for preparing a fluoro compound of formula: R.sub.2(SO.sub.2)NX(SO.sub.2)F (III) including: (a) a first step for obtaining the chloro compound of formula: R.sub.1(SO.sub.2)NX(SO.sub.2)Cl; (II) this first step including the reaction of the sulfamide of formula: R.sub.0(SO.sub.2)NH.sub.2 (I) with a sulfureous acid and a chlorinating agent; and (b) a second step for obtaining the fluoro compound of formula (III), this second step including the reaction of the chloro compound of formula (II) with anhydrous hydrofluoric acid in at least one organic solvent; in which: X represents either a hydrogen atom or a monovalent cation M; R.sub.1 represents an electron-withdrawing group having a positive Hammett parameter .sub.p; if R.sub.1 represents Cl, then R.sub.0 represents OH; otherwise, R.sub.0 is identical to R.sub.1; and if R.sub.1 represents Cl, then R.sub.2 represents F; otherwise, R.sub.2 is identical to R.sub.1.

A process for preparing a fluoro compound of formula: R.sub.2(SO.sub.2)NX(SO.sub.2)F (III) including: (a) a first step for obtaining the chloro compound of formula: R.sub.1(SO.sub.2)NX(SO.sub.2)Cl; (II) this first step including the reaction of the sulfamide of formula: R.sub.0(SO.sub.2)NH.sub.2 (I) with a sulfureous acid and a chlorinating agent; and (b) a second step for obtaining the fluoro compound of formula (III), this second step including the reaction of the chloro compound of formula (II) with anhydrous hydrofluoric acid in at least one organic solvent; in which: X represents either a hydrogen atom or a monovalent cation M; R.sub.1 represents an electron-withdrawing group having a positive Hammett parameter .sub.p; if R.sub.1 represents Cl, then R.sub.0 represents OH; otherwise, R.sub.0 is identical to R.sub.1; and if R.sub.1 represents Cl, then R.sub.2 represents F; otherwise, R.sub.2 is identical to R.sub.1.

The invention relates to a method for preparing bis(fluorosulfonyl)imide acid, comprising: the reaction of sulphamic acid or one of the salts thereof with a halogenosulfuric acid and at least one fluorinating agent selected from SOF.sub.2, FSO.sub.2F and SF.sub.4, and the subsequent recovery of bis(fluorosulfonyl)imide acid. The invention also relates to a method for producing salts of bis(fluorosulfonyl)imide from the bis(fluorosulfonyl)imide acid thus produced.

The invention relates to a method for preparing bis(fluorosulfonyl)imide acid, comprising: the reaction of sulphamic acid or one of the salts thereof with a halogenosulfuric acid and at least one fluorinating agent selected from SOF.sub.2, FSO.sub.2F and SF.sub.4, and the subsequent recovery of bis(fluorosulfonyl)imide acid. The invention also relates to a method for producing salts of bis(fluorosulfonyl)imide from the bis(fluorosulfonyl)imide acid thus produced.

Methods for preparing electrolyte salts for alkaline earth metal-ion batteries (e.g., calcium and magnesium ion batteries) are described. The electrolyte salts comprise alkaline earth metal (e.g., Mg or Ca) salts of 3,4-dicyano-2-trifluoromethylimidazole (TDI). The methods comprise contacting TDI with an alkaline earth metal bis(trifluoroacetate) salt in trifluoroacetic acid.

Methods for preparing electrolyte salts for alkaline earth metal-ion batteries (e.g., calcium and magnesium ion batteries) are described. The electrolyte salts comprise alkaline earth metal (e.g., Mg or Ca) salts of 3,4-dicyano-2-trifluoromethylimidazole (TDI). The methods comprise contacting TDI with an alkaline earth metal bis(trifluoroacetate) salt in trifluoroacetic acid.

The present invention relates to a bis(fluorosulfonyl)imide alkali metal salt (MFSI) having decomposition stability for lithium hexafluorophosphate (LiPF.sub.6) and a manufacturing method therefor.

The present invention relates to a bis(fluorosulfonyl)imide alkali metal salt (MFSI) having decomposition stability for lithium hexafluorophosphate (LiPF.sub.6) and a manufacturing method therefor.

A method for recovering lithium bis(fluorosulfonyl)imide is provided in the present application. The method of the present application may comprise: mixing a slag from lithium bis(fluorosulfonyl)imide production process with a solvent of carbonate ester, to obtain a mixed material; subjecting the mixed material to solid-liquid separation, to obtain a discharged liquid and a solid slag; monitoring the chromaticity of the discharged liquid and comparing the chromaticity of the discharged liquid with a chromaticity reference; recycling the discharged liquid to the mixed material, if the chromaticity of the discharged liquid is higher than the chromaticity reference; and recycling the discharged liquid to lithium bis(fluorosulfonyl)imide production process, if the chromaticity of the discharged liquid is lower than or equal to the chromaticity reference.

A method for recovering lithium bis(fluorosulfonyl)imide is provided in the present application. The method of the present application may comprise: mixing a slag from lithium bis(fluorosulfonyl)imide production process with a solvent of carbonate ester, to obtain a mixed material; subjecting the mixed material to solid-liquid separation, to obtain a discharged liquid and a solid slag; monitoring the chromaticity of the discharged liquid and comparing the chromaticity of the discharged liquid with a chromaticity reference; recycling the discharged liquid to the mixed material, if the chromaticity of the discharged liquid is higher than the chromaticity reference; and recycling the discharged liquid to lithium bis(fluorosulfonyl)imide production process, if the chromaticity of the discharged liquid is lower than or equal to the chromaticity reference.