Non-aqueous fluoride salts, solutions, and their uses

Patent metadata

Field	Value
Publication number	US-11069921-B2
Application number	US-202016897771-A
Country	US
Kind code	B2
Filing date	Jun 10, 2020
Priority date	Aug 4, 2015
Publication date	Jul 20, 2021
Grant date	Jul 20, 2021

Abstract

Electrolyte solutions including at least one anhydrous fluoride salt and at least one non-aqueous solvent are presented. The fluoride salt includes an organic cation having a charge center (e.g., N, P, S, or O) that does not possess a carbon in the β-position or does not possess a carbon in the β-position having a bound hydrogen. This salt structure facilitates its ability to be made anhydrous without decomposition. Example anhydrous fluoride salts include (2,2-dimethylpropyl)trimethylammonium fluoride and bis(2,2-dimethylpropyl)dimethylammonium fluoride. Combining these fluoride salts with at least one fluorine-containing non-aqueous solvent (e.g., bis(2,2,2-trifluoroethyl)ether; (BTFE)) promotes solubility of the salt within the non-aqueous solvents. The solvent may be a mixture of at least one non-aqueous, fluorine-containing solvent and at least one other non-aqueous, fluorine or non-fluorine containing solvent (e.g., BTFE and propionitrile or dimethoxyethane). The electrolyte solutions may be employed in electrochemical cells, such as batteries, fuel cells, electrolysis systems, and capacitors.

First claim

What is claimed is:

1. A method of making a fluoride ion containing solution, the method comprising:
dissolving a fluoride salt into one or more non-aqueous solvents, the fluoride salt being provided to the one or more non-aqueous solvents in an anhydrous form;
wherein the fluoride salt comprises:
one or more fluoride ions; and
an organic cation, wherein:
the organic cation does not possess a carbon in the β-position having a bound hydrogen; and
the cation charge center is N, P, S, or O;

wherein the one or more non-aqueous solvents are fluorinated and comprise at least one functional group characterized by the form [X—(CH 2 ) n —Y], where X and Y are polar functional groups having a combined effect to confer a partial positive charge on the CH 2 group or groups and n=1 or 2;
wherein the fluoride salt is a substituted or unsubstituted (2,2-dimethylpropyl)trimethylammonium fluoride (NpMe 3 NF) or a substituted or unsubstituted bis(2,2-dimethylpropyl)dimethylammonium fluoride (Np 2 Me 2 NF); and
wherein the concentration of said fluoride ions dissolved in said solution is selected from the range of 0.5 M to 20 M.

2. The method of claim 1 , wherein the concentration of said fluoride ions dissolved in said solution is greater than or equal to 1 M and less than or equal to 20 M.

3. The method of claim 1 , wherein Y is O or S and X is a functional group selected from the group consisting of ethers, esters, acid anhydrides, amines, amides, carbonates, sulfones, sulfonyl esters, phosphites, phosphates, nitriles, nitro, aldehydes, acetates, SF 5 , or fluorocarbons.

4. The method of claim 1 , wherein the one or more non-aqueous solvents are characterized by the formula (FX7a) (FX7b), (FX7c), (FX7d), (FX7e), or (FX7g):

5. The method of claim 1 , wherein the non-aqueous solvent is a fluorinated phosphite or any combination thereof and the fluorinated phosphite is characterized by the formula (FX8a):

6. The method of claim 1 , wherein the non-aqueous solvent is a fluorinated ester or anhydride or any combination thereof and the fluorinated ester or anhydride is characterized by the formula (FX9b):

7. The method of claim 1 , wherein the non-aqueous solvent is a nitrile or any combination thereof and the nitrile is characterized by the formula (FX10c):

8. The method of claim 1 , wherein the non-aqueous solvent is characterized by the formula (FX12a):

wherein R 7 is a halo group or a halogen-substituted C 1 -C 20 alkyl, C 3 -C 20 cycloalkyl, C 5 -C 30 aryl, C 5 -C 30 heteroaryl, C 1 -C 20 acyl, C 2 -C 20 alkenyl, C 3 -C 20 cycloalkenyl, C 2 -C 20 alkynyl, C 5 -C 20 alkylaryl, C 1 -C 20 alkyl, C 2 -C 20 alkoxycarbonyl, C 4 -C 30 aliphatic, C 4 -C 30 cycloaliphatic, or C 4 -C 30 aromatic; and
wherein n is an integer selected from the range of 1 to 20.

9. The method of claim 1 , the solution further comprising a second non-aqueous solvent different from the one or more non-aqueous solvents.

10. The method of claim 9 , wherein the second non-aqueous solvent is an ether or a glyme.

11. The method of claim 9 , wherein a ratio of amounts of the first solvent and the second solvent is selected from the range from 1:20 to 20:1.

12. The method of claim 1 , wherein the fluoride salt is a first fluoride salt and the step of dissolving comprises dissolving a second fluoride salt in the fluoride ion containing solution, wherein the second fluoride salt is different than the first fluoride salt, and the second fluoride salt comprises:
one or more second fluoride ions; and
a second organic cation, wherein
the cation charge center of the second organic cation is N, P, S, or O;
wherein the total concentration of fluoride ions from the first fluoride salt and the second fluoride salt dissolved in the solution is selected from the range of 0.5 M to 20 M.

13. The method of claim 1 , wherein the solution provides an ionic conductivity greater than or equal to 0.1 mS/cm at 25° C.

14. The method of claim 1 , wherein the one or more non-aqueous solvents are selected from the group consisting of bis(2,2,2-trifluoroethyl)ether (BTFE), tris(2,2,2-trifluoroethyl)phosphite (TTFP), 2,2,2-trifluoroethyl trifluoroacetate (TFE-TFA), methoxyacetonitrile (MeOAN), 3-methoxypropionitrile (3-MeOPN), and fluoroethylene carbonate (FEC).

Assignees

• California Inst Of Techn
• Honda Motor Co Ltd

Inventors

• Jones Simon C
• Davis Victoria K
• Bates Christopher M
• Momcilovic Nebojsa
• Savoie Brett M
• Webb Michael A
• Miller Iii Thomas F
• Grubbs Robert H
• Brooks Christopher
• Omichi Kaoru

Classifications

• H01M10/054

  Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium · CPC title

• H01M10/0568 Primary

  characterised by the solutes · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M2300/0028

  characterised by the solvent · CPC title

• H01M10/0569

  characterised by the solvents · CPC title