COMPOSITION

Abstract

Use of a compound of Formula 1 in a non-aqueous battery electrolyte formulation: wherein: R is an optionally fluorinated alky group, conveniently C.sub.1-6; each Y is independently H or F. X is H; a halogen, conveniently F; or an alkyl or a fluoroalkyl, conveniently C.sub.1-6; each Z is independently a halogen, conveniently F; or H.

##STR00001##

Claims

1. A method comprising providing a compound of Formula 1 in a non-aqueous battery electrolyte formulation: ##STR00013## wherein: R is an optionally fluorinated alkyl group, conveniently C.sub.1-6; each Y is independently H or F. X is H; a halogen, conveniently F; or an alkyl or a fluoroalkyl, conveniently C.sub.1-6; each Z is independently a halogen, conveniently F; or H.

2. The method of claim 1 wherein all Ys are F.

3. The method of claim 1 wherein R is CH.sub.3, CF.sub.3 or CH.sub.2CF.sub.3.

4. The method of claim 1 wherein X is H or CF.sub.3.

5. The method of claim 1 wherein Z is H or F.

6. The method of claim 1 wherein all Ys are F; R is CH.sub.3, CF.sub.3 or CH.sub.2CF.sub.3; X is H or CF.sub.3 and Z is H or F.

7. The method of claim 1 wherein each of the halogens in Z is F.

8. (canceled)

9. The method of claim 1 wherein the formulation comprises a metal electrolyte salt, present in an amount of 0.1 to 99 wt % or more relative to the total mass of the non-aqueous battery electrolyte formulation.

10. The method of claim 9, wherein the metal salt is a salt of lithium, sodium, magnesium, calcium, lead, zinc or nickel, or wherein the metal salt is selected from the group consisting of lithium hexafluorophosphate (LiPF.sub.6), lithium hexafluoroarsenate monohydrate (LiAsF.sub.6), lithium perchlorate (LiClO.sub.4), lithium tetrafluoroborate (LiBF.sub.4), lithium triflate (LiSO.sub.3CF3), lithium bis (fluorosulfonyl) imide (Li(FSO.sub.2).sub.2N) and lithium bis (trifluoromethanesulfonyl) imide (Li(CF.sub.3SO.sub.2).sub.2N).

11. (canceled)

12. The method of claim 1 wherein the formulation comprises an additional solvent in an amount of from 0.1 wt % to 99.9 wt % of the liquid component of the formulation, wherein the additional solvent is selected from the group comprising fluoroethylene carbonate (FEC), a cyclic fluoroalkyl substituted carbonate ester, an acyclic fluoroalkyl ester, propylene carbonate (PC), ethylene carbonate, ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC) or vinyl carbonate (VC), cyclic polyethers such dioxolanes for example dioxolane (DOL) and analogues of containing fluorinated substituents, polyethers such as dimethoxyethane (DME), acyclic fluorinated ethers such as 1,1,2,2-tetrafluoroethoxy-1,1,2,2-tetrafluoropropane (TTE), unsaturated ethers such as trifluoropropenyl ethers or sulphur containing compounds such as sulpholane (TMS).

13. (canceled)

14. A battery electrolyte formulation comprising a compound of Formula 1: ##STR00014## wherein: R is an optionally fluorinated alkyl group, conveniently C.sub.1-6; each Y is independently H or F. X is H; a halogen, conveniently F; or an alkyl or a fluoroalkyl, conveniently C.sub.1-6; each Z is independently a halogen, conveniently F; or H.

15. The battery electrolyte formulation of claim 14 comprising a metal ion and a compound of Formula 1 optionally in combination with a solvent.

16. A battery comprising a battery electrolyte formulation comprising a compound of Formula 1: ##STR00015## wherein: R is an optionally fluorinated alkyl group, conveniently C.sub.1-6; each Y is independently H or F. X is H; a halogen, conveniently F; or an alkyl or a fluoroalkyl, conveniently C.sub.1-6; each Z is independently a halogen, conveniently F; or H.

17. The battery electrolyte formulation of claim 14, wherein the formulation comprises a metal electrolyte salt, present in an amount of 0.1 to 100 wt % or more relative to the total mass of the battery electrolyte formulation.

18. The battery electrolyte formulation of claim 17, wherein the metal salt is a salt of lithium, sodium, magnesium, calcium, lead, zinc or nickel, or wherein the metal salt is a salt of salt of lithium selected from the group consisting of lithium hexafluorophosphate (LiPF.sub.6), lithium hexafluoroarsenate monohydrate (LiAsF.sub.6), lithium perchlorate (LiClO.sub.4), lithium tetrafluoroborate (LiBF.sub.4), lithium triflate (LiSO.sub.3CF3), lithium bis (fluorosulfonyl) imide (Li(FSO.sub.2).sub.2N) and lithium bis (trifluoromethanesulfonyl) imide (Li(CF.sub.3SO.sub.2).sub.2N).

19. (canceled)

20. The battery electrolyte formulation of claim 14, wherein the formulation comprises an additional solvent in an amount of from 0.1 wt % to 99.9 wt % of the liquid component of the formulation, wherein the additional solvent is selected from the group comprising fluoroethylene carbonate (FEC), a cyclic fluoroalkyl substituted carbonate ester, an acyclic fluoroalkyl ester, propylene carbonate (PC), ethylene carbonate, ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC) or vinyl carbonate (VC), cyclic polyethers such dioxolanes for example dioxolane (DOL) and analogues of containing fluorinated substituents, polyethers such as dimethoxyethane (DME), acyclic fluorinated ethers such as 1,1,2,2-tetrafluoroethoxy-1,1,2,2-tetrafluoropropane (TTE), unsaturated ethers such as trifluoropropenyl ethers or sulphur containing compounds such as sulpholane (TMS).

21. (canceled)

22. A method of reducing the flammability of a battery and/or a battery electrolyte comprising the addition of a formulation comprising a compound of Formula 1: ##STR00016## wherein: R is an optionally fluorinated alkyl group, conveniently C.sub.1-6; each Y is independently H or F. X is H; a halogen, conveniently F; or an alkyl or a fluoroalkyl, conveniently C.sub.1-6; each Z is independently a halogen, conveniently F; or H.

23. A method of powering an article comprising electrically coupling the article with a battery comprising a battery electrolyte formulation comprising a compound of Formula 1: ##STR00017## wherein: R is an optionally fluorinated alkyl group, conveniently C.sub.1-6; each Y is independently H or F. X is H; a halogen, conveniently F; or an alkyl or a fluoroalkyl, conveniently C.sub.1-6; each Z is independently a halogen, conveniently F; or H.

24. A method of retrofitting a battery electrolyte formulation comprising either (a) at least partial replacement of the battery electrolyte with a battery electrolyte formulation comprising a compound of Formula 1, and/or (b) supplementation of the battery electrolyte with a battery electrolyte formulation comprising a compound of Formula 1: ##STR00018## wherein: R is an optionally fluorinated alkyl group, conveniently C.sub.1-6; each Y is independently H or F. X is H; a halogen, conveniently F; or an alkyl or a fluoroalkyl, conveniently C.sub.1-6; each Z is independently a halogen, conveniently F; or H.

25. A method of preparing a compound of Formula 1 in which a compound of Formula 2: ##STR00019## is treated with an alkylating agent, wherein: each Y is independently H or F. X is H; a halogen, conveniently F; or an alkyl or a fluoroalkyl, conveniently C.sub.1-6; each Z is independently a halogen, conveniently F; or H.

26. A method of preparing a battery electrolyte formulation comprising mixing an electrolyte with the compound of Formula 1 according to claim 1.

27. A method of improving battery capacity, and/or charge transfer within a battery, and/or battery life, the method comprising introducing into a battery a formulation comprising the compound of Formula 1 according to claim 1.

28. The method according to claim 22, wherein the formulation comprises a metal electrolyte salt, present in an amount of 0.1 to 20 wt % or more relative to the total mass of the battery electrolyte formulation.

29. The method according to claim 28, wherein the metal salt is a salt of lithium, sodium, magnesium, calcium, lead, zinc or nickel, or wherein the metal salt is a salt of salt of lithium selected from the group comprising lithium hexafluorophosphate (LiPF.sub.6), lithium hexafluoroarsenate monohydrate (LiAsF.sub.6), lithium perchlorate (LiClO.sub.4), lithium tetrafluoroborate (LiBF.sub.4), lithium triflate (LiSO.sub.3CF3), lithium bis (fluorosulfonyl) imide (Li(FSO.sub.2).sub.2N) and lithium bis (trifluoromethanesulfonyl) imide (Li(CF.sub.3SO.sub.2).sub.2N).

30. (canceled)

31. The method according to claim 22, wherein the formulation comprises an additional solvent in an amount of from 0.1 wt % to 99.9 wt % of the liquid component of the formulation, wherein the additional solvent is selected from the group comprising fluoroethylene carbonate (FEC), propylene carbonate (PC) and ethylene carbonate (EC), cyclic polyethers such as dioxolanes for example dioxolane (DOL) and analogues of containing fluorinated substituents, polyethers such as dimethoxyethane (DME), acyclic fluorinated ethers such as 1,1,2,2-tetrafluoroethoxy-1,1,2,2-tetrafluoropropane (TTE), unsaturated ethers such as trifluoropropenyl ethers or sulphur containing compounds such as sulpholane (TMS).

32. (canceled)

Description

EXAMPLES

[0101] General Procedure for the Ring Opening of Fluorinated Epoxides with a Source of Cyanide

[0102] Acetone cyanohydrin, triethylamine, tetrathydrofuran and epoxide were added to a 3 necked flask charge and heated at reflux with stirring for 2 hours. The progress of the reaction was monitored by .sup.19F NMR.

[0103] Once the reaction was complete, the reaction mixture was cooled and quenched with water and then extracted twice with diethyl ether.

[0104] The ether extracts were combined and washed with 1N HCl solution and then a brine solution before being dried over anhydrous sodium sulphate. After drying, the ether was removed by distillation under vacuum.

[0105] The results are presented in Table 1 below:

TABLE-US-00001 Acetone Triethyl Epoxide cyanohydrin amine THF Yield Boiling Example (g) (g) (g) (ml) Product (%) point (? C.) 1 [00006] 4.53 5.37 20 [00007] 93 235-236 2 [00008] 2.81 5.37 20 [00009] 50.1 189-190 3 [00010] 3.89 4.62 20 [00011] 37.7

General Procedure for Alkylation of a Cyanohydrin to Produce a Cyanoether

[0106] 0.75 g of sodium hydroxide and 3 ml of water were added to a round bottomed flask and stirred. One this solution had cooled to room temperature, 0.03 g of tetrabutyl ammonium bromide was added and the solution was further cooled to 10? C. before 2.3 g of the cyanohydrin product of Example 1 was added dropwise whilst maintaining the temperature at 10-15? C. This solution was stirred for 30 minutes before 2.27 g of dimethyl sulphate was added dropwise whilst maintaining the temperature below 15? C. during the addition. This reaction mixture was allowed to warm to room temperature, and stirred overnight.

[0107] The reaction mixture was then extracted with 2?5 ml aliquots of diethyl ether, which were combined and dried over anhydrous Na.sub.2SO.sub.4 before the solvent was removed by distillation under vacuum which afforded the desired product in 71% yield:

##STR00012##

[0108] .sup.1H NMR (400 MHz, Chloroform-d) ? 3.89 (dqd, .sup.3J.sub.H-H=7.9 Hz, .sup.3J.sub.H-F=5.9 Hz, .sup.3J.sub.H-H 4.6 Hz, 1H, CH(CF.sub.3)(OMe)(CH.sub.2CN)), 3.67 (s, 3H, OCH.sub.3), 2.80-2.64 (m, 2H, CH.sub.2CN); .sup.13C NMR (101 MHz, Chloroform-d) ? 123.70 (q, .sup.1J.sub.C-F=284.3 Hz, CF.sub.3), 115.36 (s, CH.sub.2CN), 75.39 (q, .sup.2J.sub.C-F=31.3 Hz, CH(CF.sub.3)(OMe)(CH.sub.2CN)), 61.06 (q, .sup.4J.sub.C-F=1.0 Hz, OCH.sub.3), 18.94 (q, .sup.3J.sub.C-F=2.6 Hz, CH.sub.2CN); .sup.19F NMR (56 MHz,) ? ?79.35 (d, .sup.3J.sub.F-H=6.0 Hz, CF.sub.3).

Example of Flash Point Measurement

[0109] The flashpoint of the cyanoether of example 1 was measured at 64? C. using the Rapid equilibrium closed cup method (ISO 3679:2015). The flashpoint for typical battery electrolyte (1M LiPF.sub.6 in EC:EMC, 3:7, wt. %) was measured at 32? C. Therefore, addition of the cyanoether to the electrolyte will increase the flash point of the electrolyte.

Example of Electrolyte Functionality

[0110] One of the requirements to act as an electrolyte solvent is the ability to solvate the metal ion salt, which in turn will enable the salt to dissolve in the solvent. In testing, it was found that 2.5M LiPF.sub.6 salt could dissolve in pure cyanoether solvent of example 1. This confirms the ability for the cyanoether to be used as a battery electrolyte solvent.

Example of Gassing Reduction

[0111] The cyanoether material synthesized in Example 1 was tested in Li-ion cells to confirm the potential for this class of molecules to reduce gas generation.

[0112] 230 mAh dry Li-ion cells with artificial graphite as the anode, and NMC811 as the cathode were sourced from LiFun Technology Corporation in Hunan, China. These cells were filled with two different electrolytes: a control electrolyte without the cyanoether (control) and one with cyanoether (example electrolyte). The compositions of these electrolytes are listed below: [0113] Control electrolyte: EC/DEC/EMC (1/1/1, % v)+1% VC+1M LiPF.sub.6 [0114] Example electrolyte: control electrolyte+3 vol % cyanoether of example 1

[0115] Subsequently, the cells were formed using standard protocols and degassed to remove any gas generated during formation.

[0116] Following the degassing, three cells were tested for cycle life at 30? C., and 3 cells were tested at 60? C. without voltage control. As can be seen in the data below, in both cases, gas generation was reduced with the use of the cyanoether of example 1.

Cycling at 30? C.

[0117] Cells were charge/discharge cycled at 30? C. Following the cycling test, the gas generated was measured using the Archimedes method (water displacement). As can be seen from the results in FIG. 1, there is no negative impact of the cyanoether compound on the discharge capacity during cycling. Furthermore, as seen in FIG. 2, the use of cyanoether does appear to reduce the amount of gas generated.

Storage at 60? C.

[0118] 3 cells were charged to 4.3V and stored at 60? C. for 11 days. At the end of this period, the cells were discharged (retained capacity). Charged back to 4.3V, and discharged to 2.75 V (recovered capacity). As can be seen in FIG. 3, the storage at 60 C did not have a substantive impact on the recovered capacity. However, as can be seen from the results in FIG. 4, there is a measurable decrease in the amount of gas generated.

FIGURES

[0119] FIG. 1 shows capacity as a function of cycle number for cells filled with the control and example electrolytes as described in the text. Cycling conditions: 4.3V?2.75V, C/2 charge and C/2 discharge.

[0120] FIG. 2 shows a comparison of volume increase after cycling at 30? C. for cells with control and example electrolytes. The error bars display the range of measured values in the experiment.

[0121] FIG. 3 shows the discharge capacity of cells with the two different electrolytes measured before storage, immediately after storage (retained capacity) and following full charge (recovered capacity). The error bars display the range of measured values in the experiment.

[0122] FIG. 4 shows the gas generated following storage at 60? C. (as described in FIG. 3). The error bars display the range of measured values in the experiment.