Electrolyte for secondary battery, secondary battery, battery module, battery pack, and electric apparatus

Patent metadata

Field	Value
Publication number	US-2025192232-A1
Application number	US-202519059737-A
Country	US
Kind code	A1
Filing date	Feb 21, 2025
Priority date	Jan 16, 2023
Publication date	Jun 12, 2025
Grant date	—

Abstract

An electrolyte for secondary battery, a secondary battery including the electrolyte, a battery module including the secondary battery, a battery pack including the secondary battery, and an electric apparatus including the secondary battery. The electrolyte for secondary battery includes an ester solvent and an additive, where the additive includes one or more of an ionic liquid additive, an amide compound additive, an inert cation additive, and an alloy additive.

First claim

What is claimed is:

1 . An electrolyte for secondary battery, comprising an ester solvent and an additive, wherein the additive comprises one or more of an ionic liquid additive, an amide compound additive, an inert cation additive, and an alloy additive.

2 . The electrolyte according to claim 1 , wherein cations of the ionic liquid additive comprise one or more of nitrogen-containing onium ions and phosphorus-containing onium ions, and anions of the ionic liquid additive comprise one or more of halogen ions, phosphate ions, borate ions, and sulfimide anions.

3 . The electrolyte according to claim 1 , wherein the cations of the ionic liquid additive comprise one or more of 1-butyl-3-methylimidazolium, 1-benzyl-3-methylimidazolium, 3-methyl-1-ethoxycarbonyl methylimidazolium, 1-alkyl-3-methylimidazolium, 1-[(trimethylsilyl)methyl]benzotriazolium, N-alkyl-N-methylpiperidinium, 5-azoniaspiro[4.4]nonane, trihexyl(tetradecyl)phosphonium ions, tetrabutylphosphonium ions, and N-butyl-N-methylpyrrolidinium; and optionally, the cations of the ionic liquid additive comprise tetrabutylphosphonium ions or N-butyl-N-methylpyrrolidinium.

4 . The electrolyte according to claim 1 , wherein the anions of the ionic liquid additive comprise one or more of chloride ions, bromide ions, iodide ions, hexafluorophosphate, tetrafluoroborate, dicyanamide anions, bis(fluorosulfonyl)imide anions, and bis(trifluoromethylsulfonyl)imide anions; and optionally, the anions of the ionic liquid additive comprise hexafluorophosphate or bis(fluorosulfonyl)imide anions.

5 . The electrolyte according to claim 1 , wherein the ionic liquid additive comprises one or more of tetrabutylphosphonium hexafluorophosphate, tetrabutylphosphonium bis(fluorosulfonyl)imide, N-butyl-N-methylpyrrolidine hexafluorophosphate, N-butyl-N-methylpyrrolidine bis(fluorosulfonyl)imide, 1-butyl-3-methylimidazole bis(fluorosulfonyl)imide, 1-benzyl-3-methylimidazole bis(fluorosulfonyl)imide, 1-butyl-3-methylimidazole bis(trifluoromethylsulfonyl)imide, and 1-benzyl-3-methylimidazole bis(fluorosulfonyl)imide; and optionally, the ionic liquid additive comprises one or more of tetrabutylphosphonium hexafluorophosphate, tetrabutylphosphonium bis(fluorosulfonyl)imide, N-butyl-N-methylpyrrolidine hexafluorophosphate, and N-butyl-N-methylpyrrolidine bis(fluorosulfonyl)imide.

6 . The electrolyte according to claim 1 , wherein the amide compound additive comprises one or more of compounds represented by formula I, formula II, or formula III,

wherein R 1 to R 9 are each independently selected from hydrogen, silyl, keto carbonyl, C 1 -C 3 alkyl unsubstituted or substituted with at least one fluorine atom, and aryl unsubstituted or substituted with at least one fluorine atom.

7 . The electrolyte according to claim 1 , wherein the amide compound additive comprises one or more of N,N-dimethylformamide, N,N-dimethylacetamide, N,N-dimethylacetoacetamide, 1,1,1-trifluoro-N,N-dimethylmethanesulfonamide, N,O-bis(trimethylsilyl)trifluoroacetamide, 2,3,6-trifluorobenzenesulfonamide, N,N-dimethyl-4-fluorobenzenesulfonamide, and N-methyl-N-trimethylsilane trifluoroacetamide.

8 . The electrolyte according to any claim 1 , wherein the inert cation additive comprises a salt with cations being alkali metal elements or alkaline earth metal elements.

9 . The electrolyte according to claim 1 , wherein the inert cation additive comprises one or more of lithium nitrate, lithium perchlorate, lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis(oxalato)borate, lithium difluoro(oxalato)borate, lithium bis(fluorosulfonyl)imide, lithium bis(trifluoromethanesulfonyl)imide, potassium hexafluorophosphate, potassium bis(oxalato)borate, potassium difluoro(oxalato)borate, potassium bis(fluorosulfonyl)imide, potassium bis(trifluoromethanesulfonyl)imide, cesium nitrate, cesium hexafluorophosphate, cesium bis(fluorosulfonyl)imide, cesium chloride, cesium bromide, calcium nitrate, strontium nitrate, and barium nitrate.

10 . The electrolyte according to claim 1 , wherein the alloy additive is a compound containing an element of group IVA or group VA.

11 . The electrolyte according to claim 1 , wherein the alloy additive comprises one or more of antimony trifluoride, antimony pentafluoride, tin difluoride, tin tetrafluoride, bismuth trichloride, and silicon dioxide; and optionally, the silicon dioxide is fumed silica.

12 . The electrolyte according to claim 1 , wherein based on a total mass of the electrolyte, a mass percentage of the additive is 1%-10%.

13 . The electrolyte according to claim 1 , wherein the ester solvent comprises one or more of a compound represented by formula IV and a compound represented by formula V,

wherein R 10 is selected from hydrogen, alkenyl, substituted or unsubstituted C 1-6 alkyl, and substituted or unsubstituted C 1-6 alkoxy, and R 11 , R 12 , and R 13 are each independently selected from hydrogen, alkenyl, and substituted or unsubstituted C 1-6 alkyl;
R 10 and R 11 optionally form a cyclic structure with carbon and oxygen connected thereto, wherein the cyclic structure optionally has a double bond, and hydrogen on the cyclic structure is optionally substituted with halogen or C 1-3 alkyl; and
R 12 and R 13 optionally form a cyclic structure with sulfur and oxygen connected thereto.

14 . The electrolyte according to claim 1 , wherein the ester solvent comprises at least one of ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate, fluoroethylene carbonate, ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, dipropyl carbonate, methyl propyl carbonate, ethyl propyl carbonate, γ-butyrolactone, 1,3-propanesultone, methyl propionate, methyl butyrate, ethyl acetate, ethyl propionate, propyl propionate, and ethyl butyrate.

15 . The electrolyte according to claim 1 , wherein based on the total mass of the electrolyte, a mass percentage of the ester solvent is 20%-70%, optionally 40%-70%.

16 . The electrolyte according to claim 1 , wherein the electrolyte comprises a sodium salt, wherein the sodium salt comprises one or more of sodium nitrate, sodium perchlorate, sodium hexafluorophosphate, sodium tetrafluoroborate, sodium tetrafluoroyttrate, sodium hexafluoroarsenate, sodium acetate, sodium trifluoroacetate, sodium bis(oxalato)borate, sodium difluoro(oxalato)borate, sodium tetraphenylborate, sodium trifluoromethanesulfonate, sodium bis(fluorosulfonyl)imide, sodium bis(trifluoromethanesulfonyl)imide, and sodium (perfluorobutylsulfonyl)imide.

17 . The electrolyte according to claim 16 , wherein based on the total mass of the electrolyte, a mass percentage of the sodium salt is 2%-70%, optionally 30%-60%.

18 . A secondary battery, comprising the electrolyte according to claim 1 .

19 . The secondary battery according to claim 18 , wherein the secondary battery is a sodium metal battery with no negative electrode.

20 . A battery module, comprising the secondary battery according to claim 18 .

Assignees

• Contemporary Amperex Technology Hong Kong Ltd

Inventors

• Chen Shigang
• Zhang Xinxin
• Guo Bingkun
• Li Xiaolong
• Yao Shikang
• Zhou Qicheng

Classifications

• H01M4/505

  of mixed oxides or hydroxides containing manganese for inserting or intercalating light metals, e.g. LiMn2O4 or LiMn2OxFy · CPC title

• H01M4/525

  of mixed oxides or hydroxides containing iron, cobalt or nickel for inserting or intercalating light metals, e.g. LiNiO2, LiCoO2 or LiCoOxFy · CPC title

• H01M2300/0037

  Mixture of solvents · CPC title

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M10/0567 Primary

  characterised by the additives · CPC title