Cyclic phosphonamides as an electrolyte component for lithium-ion batteries

Patent metadata

Field	Value
Publication number	US-10128539-B2
Application number	US-201615527126-A
Country	US
Kind code	B2
Filing date	Sep 8, 2016
Priority date	Sep 28, 2015
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

An electrolyte suitable for use in lithium ion batteries contains
100 parts by weight of aprotic solvent, 1 to 50 parts by weight of lithium-containing conducting salt, 4 to 50 parts by weight of vinylene carbonate, and cyclic phosphonamide of the general formula 1

in which
R 1 , R 2 , R 3 are each hydrocarbyl which is unsubstituted or substituted by fluoro, chloro or silyl groups and which has 1-20 carbon atoms, where two or three of the radicals R 1 , R 2 , R 3 may be joined to one another, and
n has a value of 0, 1, 2, 3, 4 or 5. The electrolyte is used in a lithium-ion battery which comprises a cathode, an anode, a separator, and the electrolyte.

First claim

The invention claimed is:

1. An electrolyte, comprising:
100 parts by weight of at least one aprotic solvent,
1 to 50 parts by weight of at least one lithium-containing conducting salt,
4 to 50 parts by weight of vinylene carbonate, and
at least one cyclic phosphonamide of the formula 1

in which
R 1 , R 2 , R 3 are each independently hydrocarbyl radicals which are unsubstituted or substituted by fluoro, chloro or silyl groups and which have 1-20 carbon atoms, where two or three of the radicals R 1 , R 2 , R 3 may be joined to one another, and
n has a value of 0, 1, 2, 3, 4 or 5.

2. The electrolyte of claim 1 , wherein R 2 and R 3 are trimethylsilylalkyl radicals having 1-6 carbon atoms in the alkyl radical.

3. The electrolyte of claim 2 , wherein R 1 is an alkyl radical having 1 to 6 carbon atoms.

4. The electrolyte of claim 2 , wherein n has a value of 1.

5. The electrolyte of claim 1 , wherein R 1 is an alkyl radical having 1 to 6 carbon atoms.

6. The electrolyte of claim 5 , wherein n has a value of 1.

7. The electrolyte of claim 1 , wherein n has a value of 1.

8. The electrolyte of claim 1 , wherein the electrolyte comprises 0.1 to 10 parts by weight of cyclic phosphonamide(s) of the formula 1.

9. The electrolyte of claim 1 , wherein at least one aprotic solvent is selected from the group consisting of organic carbonates, cyclic and linear esters, cyclic and linear ethers, ketones, lactones, sulfolanes, dimethyl sulfoxide, formamide, dimethylformamide, 3-methyl-1,3-oxazolidine-2-one and mixtures of these solvents.

10. The electrolyte of claim 1 , wherein at least one lithium-containing conducting salt is selected from the group consisting of LiPF 6 , LiBF 4 , LiClO 4 , LiAsF 6 , LiSO 3 CxF 2x+1 , (LiB(C 2 O 4 ) 2 , LiBF 2 (C 2 O 4 )), LiN(SO 2 C x F 2x+1 ) 2 and LiC(SO 2 C x F 2x+1 ) 3 , where x adopts integral values from 0 to 8, and mixtures thereof.

11. The electrolyte of claim 1 , which comprises 0.1-10 wt % of cyclic phosphonamide(s) of the formula 1.

12. A lithium-ion battery, comprising: a cathode, an anode, a separator, and an electrolyte of claim 1 .

13. The lithium-ion battery of claim 12 , wherein the anode is a silicon-containing anode.

Assignees

• Wacker Chemie Ag

Inventors

• Braeunling Daniel
• Deubel Frank

Classifications

• H01G11/64

  characterised by additives · CPC title

• H01G11/62

  characterised by the solute, e.g. salts, anions or cations therein · CPC title

• H01M10/052

  Li-accumulators · CPC title

• C07F7/0803

  Compounds with Si-C or Si-Si linkages · CPC title

• H01M10/0569

  characterised by the solvents · CPC title