Stabilization of alkali metal PF6 salts in carbonate solutions.

Abstract

Disclosed herein is a stabilized salt-in-solvent mixture comprising a salt, a carbonate solvent, and an organosilicon (OS) compound, wherein the OS compound inhibits decomposition reactions within the salt-in-solvent mixture.Disclosed herein is also a method for mitigating decomposition of a salt / carbonate solution, comprising adding to the salt / carbonate solution an OS compound that inhibits decomposition reactions within the salt / carbonate solution.The OS compound can be added to the carbonate solution before or after dissolution of the salt to form the salt-in-solvent mixture.

Description

[Background technology]

[0001] Lithium hexafluorophosphate (LiPF 6 LiPF is the most common lithium salt used in lithium-ion battery technology today. While it has many useful properties as a battery ionic conductor, this material is quite susceptible to decomposition by several different mechanisms. These various decomposition pathways are accelerated by increasing temperature. This decomposition is characterized by the formation of LiPF 6 This is an ongoing problem even before the salt is formulated into an electrolyte and incorporated into a battery. Before it can be made into a battery, the salt must be stored and then undergo a multi-step process of electrolyte formulation and production. Throughout the storage and electrolyte production process, the salt is prone to decomposition, which ultimately reduces the performance of the battery in which it is incorporated. Other candidate alkali metal salts include NaPF 6 However, this salt suffers from similar problems.

[0002] Thus, there is a long-felt unmet need to mitigate the decomposition of electrolyte salts in simple or complex solvent systems. Summary of the Invention

[0003] Disclosed herein is a stabilized salt-in-solvent mixture for use in electrolyte formulations for lithium ion charge storage devices (such as batteries). The mixture includes a salt, a carbonate solvent, and an organosilicon (OS) compound disclosed herein, where the OS compound inhibits decomposition reactions within the salt-in-solvent mixture. Also disclosed herein is a method for preventing LiPF 2 from being decomposed by inhibiting thermal and chemical decomposition in the composition. 6 - or NaPF 6 Also disclosed are corresponding methods of enhancing the storage stability of OS-containing compositions by incorporation into the compositions of one or more OS compounds disclosed herein.

[0004] In one particular version, the stabilized salt-in-solvent mixture is LiPF 6 or NaPF 6 and linear carbonates such as ethyl methyl carbonate (EMC), and OS compounds.

[0005] Also disclosed herein is a method of mitigating decomposition of a salt / carbonate solution for use in an electrolyte formulation or in the formulated electrolyte itself, both before and after the electrolyte is incorporated into a lithium ion battery or other rechargeable battery device. The method includes adding to the salt / carbonate solution an amount of an OS compound that inhibits decomposition reactions within the salt / carbonate solution. The OS compound may be added to the carbonate solvent before or after dissolving the salt to form a salt-in-solvent mixture.

[0006] As used herein, an OS compound is [ka] (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b" = 0) is "R" and [ka] selected from the group consisting of; Each "R" is independently halogen, C 1-6 Straight or branched alkyl, alkenyl, or alkynyl of C 1-6 is selected from the group consisting of straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 linear or branched alkylenyl, and C 1-15 and Each "Y" in formula I is independently selected from the group consisting of organic polar groups. is selected from the group consisting of:

[0007] In some versions of the compound, each "Y" is independently: [ka] (wherein the curved bond is C 2-6 (Indicates the alkylene bridge portion) is an organic polar group selected from the group consisting of:

[0008] Exemplary OS compounds within the scope of the present disclosure have the structure: [ka] F1S with 3 MN (4-(fluorodimethylsilyl)butanenitrile).

[0009] Exemplary OS compounds within the scope of the present disclosure have the structure: [ka] DF1S with 2 MN (3-(difluorodimethylsilyl)propanenitrile).

[0010] Specifically, the following compositions and methods are disclosed and claimed herein:

[0011] 1. A stabilized salt-in-solvent mixture comprising a salt, a carbonate solvent; and an organosilicon compound, said organosilicon compound inhibiting decomposition reactions within said salt-in-solvent mixture.

[0012] 2. The above salt is an alkali metal PF 6 2. The stabilized salt-in-solvent mixture of claim 1, which is a salt.

[0013] 3. The above salt is LiPF 6 and NaPF6 3. The stabilized salt-in-solvent mixture of claim 2, selected from the group consisting of:

[0014] 4. The stabilized salt-in-solvent mixture of claim 2, wherein said carbonate is a linear carbonate.

[0015] 5. The stabilized salt-in-solvent mixture of claim 2, wherein the carbonate is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate, ethylene carbonate, propylene carbonate, and gamma-butyrolactone.

[0016] 6. The organosilicon compound is [ka] (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b" = 0) is "R" and [ka] selected from the group consisting of; Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 linear or branched alkylenyl, and C 1-15 and Each "Y" in formula I is independently selected from the group consisting of organic polar groups. 3. The stabilized salt-in-solvent mixture of claim 2, selected from the group consisting of:

[0017] 7. Each "Y" independently represents: [ka] TIFF2025515715000010.tif67139 (wherein the curved bond is C 2-6 (Indicates the alkylene bridge portion) 7. The stabilized salt-in-solvent mixture of claim 6, wherein the organic polar group is selected from the group consisting of:

[0018] 8. Each "Y" independently represents: [ka] 8. The stabilized salt-in-solvent mixture of claim 7, wherein the organic polar group is selected from the group consisting of:

[0019] 9. The organosilicon compound is [ka] 3. The stabilized salt-in-solvent mixture of claim 2, wherein

[0020] 10. The organosilicon compound is [ka] 3. The stabilized salt-in-solvent mixture of claim 2, wherein

[0021] 11. A stabilized salt-in-solvent mixture according to any one of claims 1 to 10 for use in an electrolyte formulation.

[0022] 12. A stabilized salt mixture in a solvent, comprising an alkali metal PF 6 salt, carbonate solvent; and [ka] (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b" = 0) is "R" and [ka] selected from the group consisting of; Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 linear or branched alkylenyl, and C 1-15 and Each "Y" in formula I is independently [ka] TIFF2025515715000017.tif68139 (wherein the curved bond is C 2-6 (representing an alkylene bridging moiety) and an organosilicon compound selected from the group consisting of: A stabilized salt-in-solvent mixture, wherein the organosilicon compound inhibits decomposition reactions within the salt-in-solvent mixture.

[0023] 13. The stabilized salt-in-solvent mixture of claim 12, wherein the carbonate is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate, ethylene carbonate, propylene carbonate, and gamma-butyrolactone.

[0024] 14. Each "Y" independently represents: [ka] 13. The stabilized salt-in-solvent mixture of claim 12, wherein the organic polar group is selected from the group consisting of:

[0025] 15. The organosilicon compound is [ka] 13. The stabilized salt-in-solvent mixture of claim 12, wherein

[0026] 16. The organosilicon compound is [ka] 13. The stabilized salt-in-solvent mixture of claim 12, wherein

[0027] 17. The above salt is LiPF 6 and NaPF 6 13. The stabilized salt-in-solvent mixture of claim 12, selected from the group consisting of:

[0028] 18. A stabilized salt-in-solvent mixture according to any one of claims 12 to 17 for use in an electrolyte formulation.

[0029] 19. A method for mitigating degradation of a salt / carbonate solution for use in an electrolyte formulation or formulated electrolyte, the method comprising adding to the salt / carbonate solution: [ka] (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b" = 0) is "R" and [ka] selected from the group consisting of; Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15linear or branched alkylenyl, and C 1-15 and Each "Y" in formula I is independently [ka] TIFF2025515715000024.tif140143 (wherein the curved bond is C 2-6 (representing an alkylene bridging moiety) adding an organosilicon compound selected from the group consisting of The method, wherein the organosilicon compound inhibits decomposition reactions in a salt mixture in a solvent.

[0030] 20. A stabilized salt-in-solvent mixture comprising an alkali metal PF6 salt, a carbonate solvent; and an organosilicon compound, wherein the concentration of hydrofluoric acid (HF) in the mixture is less than about 100 ppm after storage at 100° C. for 20 days.

[0031] 21. The stabilized salt-in-solvent mixture of claim 20, wherein the concentration of hydrofluoric acid (HF) in the mixture is less than about 20 ppm after storage at 100° C. for 20 days.

[0032] 22. The stabilized salt-in-solvent mixture of claim 20, wherein the concentration of hydrofluoric acid (HF) in the mixture is less than about 10 ppm after storage at 100° C. for 20 days.

[0033] 23. The stabilized salt-in-solvent mixture of claim 20, wherein the concentration of hydrofluoric acid (HF) in the mixture is less than about 5 ppm after storage at 100° C. for 20 days.

[0034] 24. The organosilicon compound is [ka] (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b" = 0) is "R" and [ka] selected from the group consisting of; Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 linear or branched alkylenyl, and C 1-15 and Each "Y" in formula I is independently [ka] TIFF2025515715000028.tif112139 (wherein the curved bond is C 2-6 (representing an alkylene bridging moiety) selected from the group consisting of; 21. The stabilized salt-in-solvent mixture of claim 20, wherein the organosilicon compound inhibits decomposition reactions within the salt-in-solvent mixture.

[0035] 25. The stabilized salt-in-solvent mixture of claim 20, wherein the carbonate is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate, ethylene carbonate, propylene carbonate, and gamma-butyrolactone.

[0036] 26. The concentration of the organosilicon compound is represented by the formula:

number

[0037] 27. The organosilicon compound is [ka] (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b" = 0) is "R" and [ka] selected from the group consisting of; Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 linear or branched alkylenyl, and C 1-15 and Each "Y" in formula I is independently [ka] TIFF2025515715000033.tif113139 (wherein the curved bond is C 2-6 (representing an alkylene bridging moiety) selected from the group consisting of; 21. The stabilized salt-in-solvent mixture of claim 20, wherein the organosilicon compound inhibits decomposition reactions within the salt-in-solvent mixture.

[0038] 28. The stabilized salt-in-solvent mixture of claim 27, wherein the carbonate is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate, ethylene carbonate, propylene carbonate, and gamma-butyrolactone.

[0039] The objects and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiment of the invention taken in conjunction with the accompanying drawings. [Brief description of the drawings]

[0040] [Figure 1A] Autocatalytic HF production in salt-in-solvent mixtures (top panel; HF is a decomposition marker) and reduced HF production in organosilicon (OS) nitrile formulations (bottom panel) are shown. Salt-in-solvent mixtures of ethylene carbonate / diethyl carbonate (EC / DEC) (3 / 7, %v) and 1M LiPF6 at 100 °C are shown as controls. A series of solutions were prepared with the addition of 100 ppm HO (+100 ppm) and 500 ppm HO (+500 ppm) and compared to no added HO (+0 ppm). In Figure 1A, the labels on the side of the curves indicate the amount of HO added prior to thermal storage. [Figure 1B] Decomposition of LiPF6 with and without added OS is shown. OS does not increase decomposition of the LiPF6 salt. EC / DEC (3 / 7, %v) and 1M LiPF6 salt mixture in solvent at 100 °C serve as controls. A series of solutions were prepared with the addition of 100 ppm H2O (+100 ppm) and 500 ppm H2O (+500 ppm) and compared to no added H2O (+0 ppm). Labels on the side of the curve indicate the amount of H2O added before thermal storage. [Figure 1C]An exemplary chemical reaction of HF elimination by an OS nitrile (F1S3MN; top panel) is shown, which scavenges H+ and forms three amide species (bottom left panel) and one ether (bottom right panel). [Figure 1D] Figure 1 shows HF reduction (top panel) and amide formation (bottom panel) in salt mixtures in solvents containing EC / DEC, 1M LiPF6, and OS nitrile. A series of solutions was prepared with the addition of 100 ppm HO (+100 ppm) and 500 ppm HO (+500 ppm) and compared to no added HO (+0 ppm). In the bottom panel, the labels on the side of the curve indicate the amount of HO added before thermal storage. [Figure 2A] 19F NMR spectrum of an OS / PF5 complex with an exemplary OS nitrile (F1S3MN). The composition includes F1S3MN and 1M LiPF6 at 100° C. for 260 days. [Figure 2B] 19F NMR spectrum of OS / PF5 complex with an exemplary OS nitrile (F1S3MN) in carbonate blend. The composition includes EC / F1S3MN (volume ratio 2 to 8) and 1M LiPF6 at 100° C. for 260 days. [Figure 3A] HF production in a salt-in-solvent mixture containing EC / EMC and 1M LiPF6 at 100° C. (top panel) and 70° C. (bottom panel) is shown. HF production is clearly autocatalytic at 100° C., but not at the lower temperature of 70° C. [Figure 3B] Storage of salt-in-solvent mixtures containing OS nitriles (F1S3MN; DF1S2MN) at 30°C for 141 days is shown. Salt-in-solvent with no added OS nitrile serves as control. A series of solutions was prepared with the addition of 500 ppm H2O (+500 ppm) and compared to no added H2O (nominal moisture). [Figure 3C]Storage at 45 °C for 141 days for salt-in-solvent mixtures containing OS nitriles (F1S3MN; DF1S2MN) is shown (top panel). Salt-in-solvent mixtures with no added OS nitriles serve as control. A series of solutions were prepared with the addition of 500 ppm HO (+500 ppm) to compare with no added HO (nominal moisture). The table in the bottom panel shows the reduction in HF from 70 to 141 days for the control salt-in-solvent mixtures and the salt-in-solvent mixtures with OS nitriles. [Figure 4A] We show reduced HF generation in salt-in-solvent mixture formulations containing multiple OS nitrile molecules. All OS nitriles are present at 0.13 M in a salt-in-solvent mixture of ethylene carbonate / diethyl carbonate (EC / DEC) (3 / 7, %v) and 1M LiPF6. No water was added to the salt-in-solvent mixture prior to thermal storage. For 0.13 M OS, the F1S2MN and TFT1S2MN curves overlap such that only the TFT1S2MN curve is visible. [Figure 4B] We demonstrate the reduction of HF generation in salt-in-solvent mixture formulations containing multiple OS nitrile molecules. All OS nitriles are present at 1 M in a salt-in-solvent mixture of ethylene carbonate / diethyl carbonate (EC / DEC) (3 / 7, %v) and 1M LiPF6. No water was added to the salt-in-solvent mixture prior to thermal storage. [Figure 5A] The reduction in HF production in solvent-based salt mixture formulations containing other nitriles (succinonitrile, adiponitrile, and valeronitrile; structures of compounds are shown to the right) compared to OS, F1S3MN at 100 °C. A series of solutions was prepared with the addition of 500 ppm HO (+500 ppm HO) and compared to no added HO (No HO). [Figure 5B] Decomposition of other nitriles (succinonitrile, adiponitrile, and valeronitrile) compared to OS, F1S3MN at 100° C. A series of solutions were prepared with the addition of 500 ppm H2O (+500 ppm H2O) and compared to no added H2O (No H2O). [Figure 6]This shows the reduction in HF production in a solvent-based salt mixture formulation containing compounds with a trifluoro structure including TF1S2MN, TF-BN (trifluorobutyronitrile), and TF1S6M (no nitrile) at 100° C. The structures of the compounds are shown below. [Figure 7A] Figure 2 shows the HF concentration in solvent-based salt mixture formulations containing EC and various concentrations of OS, F1S3MN, at 100° C. (left panel: 1% and 2% OS; right panel: 5%, 8%, 16%, 20%, and 87% OS). The dielectric constant of the EC blend is 89. [Figure 7B] Figure 1 shows the HF concentration in salt-in-solvent mixture formulations containing EC / DEC (3 / 7) and various concentrations of OS (0%, 2%, 5%, 10%, and 16%) at 100° C. The dielectric constant of the EC / DEC blend is 21.8. [Figure 7C] Figure 1 shows HF production in a salt-in-solvent mixture formulation containing high salt EMC and 2.5M LiPF6 at 100°C. HF production with the addition of 500 ppm H2O (+500 ppm H2O) was compared to no added H2O (nominal moisture). [Figure 7D] Figure 1 shows the reduction in HF production in salt-in-solvent mixture formulations containing high salt EMC, 2.5M LiPF6, and various concentrations of OS at 100°C. Salt-in-solvent mixtures without OS serve as controls. No water was added to the mixtures prior to thermal storage. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0041] The elements and method steps described herein can be used in any combination or order, whether or not explicitly disclosed.

[0042] All combinations of method steps used in this specification can be performed in any order, unless otherwise specified or clearly implied to the contrary by the context in which the referenced combination occurs.

[0043] The systems disclosed herein may comprise, consist of, or consist essentially of the various steps and elements disclosed herein, and the disclosure provided herein per se can be practiced in the absence of any element or step not specifically disclosed herein.

[0044] All references herein to features or limitations in the singular include the corresponding features or limitations in the plural, and vice versa, unless otherwise specified or clearly implied to the contrary, in the context of reference. The indefinite articles "a" and "an" mean "one or more."

[0045] Numeric ranges used herein are intended to include all numbers and subsets of numbers contained within the range, whether or not specifically disclosed. Moreover, these numerical ranges should be construed to support a claim that refers to any number or subset of numbers within the range. For example, a disclosure of "1 to 10" should be construed to support the ranges "2 to 8," "3 to 7," "5 to 6," "1 to 9," "3.6 to 4.6," "3.5 to 9.9," etc.

[0046] All patents, patent publications, and peer-reviewed publications cited herein (i.e., "references") are expressly incorporated by reference to the same extent as if each reference was expressly and individually indicated by reference. In the event of a conflict between the present disclosure and the incorporated references, the present disclosure controls.

[0047] It is understood that the compounds and compositions disclosed herein are not limited to the particular structures and arrangements of parts shown and described herein, but also encompass such modifications thereof as are encompassed by the scope of the claims.

[0048] Alkaline metal PF 6 Salt decomposition mechanism: LiPF 6 Alkaline metal PFs such as6 Salts are known to have at least two decomposition mechanisms when present in carbonate-based solvent systems: the first is through interaction with any amount of water that may be present in the system. [ka]

[0049] This reaction produces the strong acid hydrofluoric acid (HF) and insoluble LiF, which then catalyzes the decomposition of the carbonate material, resulting in the production of more HF due to the further decomposition of the carbonate components and the production of insoluble LiF. [ka]

[0050] In the industry, LiPF 6 Although great care is taken to keep water contamination of the carbonate solution as low as possible, it is difficult and expensive to eliminate completely.

[0051] Furthermore, LiPF 6 There is a second mechanism that can break down the [ka]

[0052] LiPF in carbonate solution 6 Always LiF-PF 5 It turns out that the pair is in equilibrium with PF. This equilibrium shifts to the right at higher temperatures. 5 The molecule is a highly reactive gas molecule and reacts immediately with the carbonate carrier material, resulting in a carbonate decomposition reaction that also produces HF and is autocatalytic, once initiated the carbonate decomposition reaction accelerates over time.

[0053] H by amines+ Capture of: PF 6 -1 It should be noted that the decomposition of carbonates in the presence of anions leads to the production of HF, and the decomposition of carbonates generally tends to produce acidic species that catalyze further decomposition. + Trapping the acid is essential to stop its decomposition. One way that acids can be trapped is by reacting them with amines to form ammonium salts. The reaction of amines with acids is well known and is an effective way to remove acidic hydrogen from solution by trapping it in a stable salt with an N-H bond. Organosilicon amines are capable of trapping H present in a solvent-salt mixture or electrolyte. + By trapping cations, HF and other acidic compounds can be instantly reduced.

[0054] Alkali metal PF using organosilicon compounds 6 Mitigating salt decomposition: Disclosed herein is a stabilized salt-in-solvent mixture that includes a salt, a carbonate solvent, and an organosilicon (OS) compound, where the OS compound inhibits, inhibits, and otherwise retards decomposition reactions within the salt-in-solvent mixture. The stabilized salt-in-solvent mixture can be used as an electrolyte formulation for Li-ion batteries.

[0055] As used herein, salt is intentionally defined broadly to include all salts, including, but not limited to, lithium salts, sodium salts, potassium salts, magnesium salts, borates, phosphates, etc. Non-limiting examples include lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, sodium hexafluorophosphate, sodium tetrafluoroborate, sodium perchlorate, potassium hexafluorophosphate, potassium tetrafluoroborate, potassium perchlorate, magnesium hexafluorophosphate, magnesium perchlorate, magnesium tetrafluoroborate, tetraethylammonium tetrafluoroborate (TEA-TFB), tetrabutylphosphonium tetrafluoroborate, tetrabutylphosphonium hexafluorophosphate, tetrabutylammonium tetrafluoroborate, tetraethylammonium hexafluorophosphate, and tetraethylammonium perchlorate.

[0056] Traditionally, carbonates have been used as solvents in electrolyte compositions. Non-limiting examples of carbonate solvents include linear carbonates such as ethyl methyl carbonate (EMC), dimethyl carbonate (DMC), and diethyl carbonate (DEC); cyclic carbonates such as ethylene carbonate (EC), propylene carbonate (PC), and γ-butyrolactone; and various fluorine-containing linear or cyclic carbonates. The salt-in-solvent mixture can include a carbonate solvent or carbonate solvent mixture in a wide range of concentrations, including but not limited to, about 90% to about 100% by weight of the total solvent. Examples of suitable carbonate solvent total concentrations include about 90% by weight, about 95% by weight, about 97% by weight, about 98% by weight, about 99% by weight, about 99.5% by weight, about 99.97% by weight, or ranges between and including any of these amounts of the total solvent.

[0057] The OS compounds used herein are described in detail in the following section. The salt mixture in the solvent can contain the OS compound in a wide range of concentrations, including but not limited to, about 0.03% to about 10% by weight of the total solvent. Examples of suitable OS compound concentrations include about 0.03%, about 0.5%, about 1%, about 2%, about 3%, about 5%, about 10% by weight, or any of these amounts, inclusive ranges, based on the total weight of the solvent.

[0058] As disclosed herein, OS molecules have properties that can mitigate both forms of salt decomposition described above. The first use case for OS-based nitrile materials is LiPF 6 This can be demonstrated in the case of free water present in LiPF / carbonate systems. 6 When reacting with , the OS nitrile molecule acts as a proton trap, preventing it from reacting preferentially with the acidic component and causing further autocatalytic decomposition in its HF form. Figure 1A compares the HF reduction observed in the solvent-salt mixtures containing OS nitriles with the autocatalytic HF production in the carbonate-based control mixture, and Figure 1B shows the suppression of total salt decomposition in the OS nitrile mixtures. These are compared to the same systems with added water (+100 ppm, +500 ppm). Figures 1C and 1D show that the OS nitriles capture the hydrogen into a stable amide structure.

[0059] The table below shows the calculated equivalent amount of water that can be accommodated by the stabilization of the HF formed above by the proton trapping mechanism of the OS if the water were completely converted to HF (1 mole of OS to 1 mole of HF). Equivalent ppm H based on HF stabilized by OS in carbonate solvent. 2 O is calculated using the following formula:

number

[0060] [Table 1]

[0061] The above formula can also be used to estimate the required OS concentration for a given amount of water impurity in a salt-in-solvent mixture.

number

[0062] Furthermore, experiments have demonstrated that OS nitriles are produced by the equilibrium reaction of PF 5 It has been shown that the fluorine-containing carbonate can form complexes with the fluorine-containing carbonate species, again mitigating further decomposition of the carbonate solution by autocatalysis. Figures 2A and 2B show typical OS nitriles (F1S 3 MN) and OS / PF 5 The NMR spectrum of the complex is shown.

[0063] Both potential decomposition pathways were mitigated, resulting in LiPF 6 Carbonate systems offer significantly improved storage stability over time and temperature, whether stored in simple containers or fully assembled batteries or other rechargeable devices.

[0064] By preventing both of the above decomposition mechanisms from occurring, the methods described herein provide a method for preventing LiPF 6 This allows carbonate solutions (and other salt solutions) to be kept purer for longer periods and at higher temperatures, which is of great benefit to industry. 6The base components can be stored for longer periods while in the supply chain (before production), allowing suppliers more leeway to adjust inventory to meet just-in-time manufacturing needs. The timely flow of products through the supply chain is significantly improved because the products can be stored for longer periods without degrading. This also improves the shelf life of finished products (batteries, capacitors, and other charging and storage devices) that utilize the targeted electrolyte compositions.

[0065] Thus, also disclosed herein is a method for mitigating the decomposition of a salt / carbonate solution for use in an electrolyte formulation or in a formulated electrolyte itself.The method includes adding an amount of an organosilicon compound to the salt / carbonate solution that inhibits decomposition reactions within the salt / carbonate solution.The organosilicon compound can be added to the carbonate solvent before or after adding the salt.

[0066] Three typical applications of this method and the advantages of using this method are described herein.

[0067] First, LiPF 6 The formation of the salt is a highly specialized process, made even more challenging by the extremely reactive nature of the salt, especially with water. By introducing the salt into a highly concentrated solution of a simple carbonate solvent as early as possible in the manufacturing process, a certain amount of the OS-nitrile material can also be introduced, stabilizing the solution and preventing decomposition by either or both of the two mechanisms mentioned above. This stable LiPF 6 The solution contains LiPF, which is used in the electrolyte formulation. 6 The salt component can be provided to formulators as a high purity, shelf stable component, providing greater purity to the final formulated electrolyte product.

[0068] For example, LiPF 6A linear carbonate, such as ethyl methyl carbonate (EMC), is often used as a solvent during salt production. The salt is stored in this solvent and sent to an electrolyte manufacturer, where the LiPF 6 The linear carbonate solution is combined with other ingredients, such as cyclic carbonates and other additives, to produce the final battery electrolyte formulation. As defined in this disclosure, the salt-in-solvent mixture itself is not considered a Li-ion battery electrolyte, since it lacks the components necessary for a functional, commercially acceptable electrolyte. These additional materials are necessary to form a suitable interface on the active material of the Li-ion battery to maximize battery performance. Thus, as used herein, LiPF 6 Disclosed is a salt-in-solvent mixture comprising a salt, a linear carbonate such as EMC, and an OS material that inhibits decomposition reactions within the salt-in-solvent mixture. The addition of the OS to the salt-in-solvent mixture significantly extends the shelf life of the salt-in-solvent mixture. For example, the salt-in-solvent mixture with the added OS material can be stored for more than six months and can be further formulated into a commercially acceptable electrolyte for lithium-ion batteries.

[0069] The second typical application concerns the introduction of a certain amount of OS-nitrile material into the already formulated electrolyte itself, again increasing the stability of the newly formulated electrolyte and improving its resistance to accidental moisture and temperature storage conditions. This improves the entire lithium battery manufacturing flow, providing cell manufacturers with more flexibility in terms of the shelf life of the required components and the ultimate operational life of the electrolyte formulation.

[0070] The third typical application concerns the preparation process of salt and electrolyte solutions in solvents. Basically, a salt is mixed in a solvent or solvent mixture. LiPF in a carbonate solvent (e.g., EMC, DMC, or DEC) 6The heat of mixing of salts such as ZnO, ZnO, and ZnO is extremely high. Therefore, localized hot spots can occur during the mixing process. The temperature increase in these hot spot areas can accelerate the aforementioned decomposition reactions. In current electrolyte manufacturing processes, great attention is paid to preventing the occurrence of hot spots during electrolyte preparation by active temperature management to remove heat. Such mitigation measures increase the cost and complexity of the electrolyte formulation. Here, we disclose a new approach to overcome these mixing challenges. By first mixing the OS material (of the present invention) with the carbonate solvent before the addition of the salt, it is possible to eliminate or reduce the temperature-induced decomposition reactions.

[0071] Organosilicon compounds: The disclosure includes a class of materials, namely organosilicon (OS) compounds, that inhibit the decomposition pathways of electrolyte salts by interacting with the salts in simple or complex solvent systems.

[0072] Preferred OS compounds are [ka] (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b" = 0) is "R" and [ka] selected from the group consisting of; Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 linear or branched alkylenyl, and C 1-15 and Each "Y" in formula I is independently selected from the group consisting of organic polar groups. is selected from the group consisting of:

[0073] In some versions of the compound, each "Y" independently represents: [ka] TIFF2025515715000043.tif66139 (wherein the curved bond is C 2-6 (Indicates the alkylene bridge portion) is an organic polar group selected from the group consisting of:

[0074] In a more limited version of the compound, each "Y" is independently [ka] is an organic polar group selected from the group consisting of:

[0075] Further, each "Y" may optionally and independently [ka] The organic polar group may be selected from the group consisting of:

[0076] In alternative versions of the compounds, "a" is 1 and "b" is 0-2; optionally "b" is 1 and "Z" is R. In this version, any embodiment includes at least one "R" being fluorine, and each "Sp" is independently an optionally fluorinated C. 1-6 It is selected from the group consisting of straight or branched chain alkylene.

[0077] In another alternative version of the compound, "a" is 2 and "b" is 0-6; optionally "b" is 1 and "Z" is R. In this version, an optional embodiment includes at least one "R" being fluorine, and each "Sp" is independently an optionally fluorinated C.1-6 It is selected from the group consisting of straight or branched chain alkylene.

[0078] In yet another alternative version of the compound, "a" is 3 and "b" is 0-9; optionally "b" is 1 and "Z" is R. In this version, any embodiment includes at least one "R" being fluorine, and each "Sp" is independently an optionally fluorinated C. 1-6 It is selected from the group consisting of straight or branched chain alkylene.

[0079] In yet another alternative version of the compound, "a" is 4 and "b" is 0-12; optionally "b" is 1 and "Z" is R. In this version, any embodiment includes at least one "R" being fluorine, and each "Sp" is independently an optionally fluorinated C. 1-6 It is selected from the group consisting of straight or branched chain alkylene.

[0080] By the nature of the subscripts "a" and "b," the following general structures are clearly within the scope of the compounds disclosed and claimed herein. [ka] The various R groups are as defined above for "R"; Sp is as defined above, and Y is as defined above.

[0081] When the polar group Y has a valency of two (2) or more, it will have more than one substitution site. Thus, more than one silicon atom may be attached to Y by a spacer group as defined above for Z. Thus, the following structures are expressly within the scope of the compounds disclosed and claimed herein: [ka]

[0082] In all versions of the compounds, "halogen" includes fluoro, chloro, bromo, and iodo. Fluoro and chloro are preferred halogen substituents.

[0083] A subgroup of the OS compounds disclosed herein has the general formula: [ka] (In the formula, R 1 , R 2 , and R 3 are the same or different and independently C 1 ~C 6 and the "spacer" is selected from the group consisting of straight or branched chain alkyl, alkenyl, alkynyl, or halogen (preferably F), 1 ~C 6 Linear or branched alkylene (preferably C 1 ~C 6 linear divalent alkylene), and Y is a polar organic moiety as previously described. The compound is an FnSnMN compound having the formula:

[0084] The compounds disclosed herein can be made by a number of different routes. The general approaches that can be used to prepare the compounds are as follows: [ka]

[0085] R 1 , R 2 , and R 3 The group is as defined herein for R; R 4 has the same definition as Y; and "n" is a positive integer.

[0086] The compounds disclosed herein may be prepared by the following approaches. [ka]

[0087] Again, R 1 , R 2 , and R 3 The group is as defined herein for R; R 4 has the same definition as Y.

[0088] The compounds disclosed herein may also be made by a number of specific routes, including the following reaction schemes. [ka] TIFF2025515715000052.tif203139

[0089] The compounds currently disclosed are organosilicon compounds that share a common structural feature in the form of one or more terminal or internal polar organic substituents or moieties.As used herein, the terms "polar organic substituent" and "polar organic moiety" are used interchangeably.These terms expressly include, but are not limited to, the following functional groups: [ka] TIFF2025515715000054.tif109129

[0090] Among the preferred compounds are the following structures: [ka] TIFF2025515715000056.tif167117

[0091] The above structures are all drawn with a terminal cyano group. This is for simplicity only. Analogous compounds with the above-mentioned internal and / or terminal polar moieties in place of the cyano moiety are clearly within the scope of the disclosure. Similarly, the halogenated compounds are depicted above as fluorinated compounds. Analogous compounds with other halogen substituents (chlorine, bromine, and / or iodine) in place of the fluorine atom are clearly within the scope of the disclosure. Two alternative systematic names are given for the listed compounds (the first of each pair of names designates the base core as a nitrile, the second designates the base core as a silane). Additionally, abbreviations are provided for each compound, DF=difluoro, TF=trifluoro, and "Sn" designates an alkylene spacer between the silicon atom and the terminal cyanate, isocyanate, or thiocyanate moiety, and "n" represents the number of carbon atoms in the spacer.

[0092] Synthesis of similar sulfones: 3 MS, and DF1S 3 The following exemplary synthesis of MS can be used: Other sulfones falling within the broader disclosure contained herein can be made by the same route by simply varying the starting reagents.

[0093] The synthesis of 1NMS proceeded as follows: 2-(methylsulfonyl)ethanol was dissolved in 0.5 mol equivalents of hexamethyldisilazane and approximately 1% mol equivalents of Al(H) as a catalyst. 2 PO 4 ) 3 and mixed without solvent. The mixture was kept at about 80°C overnight and distilled twice to obtain pure 1NMS. [ka]

[0094] F1S 3 The synthesis of MS proceeded as follows: Allyl methyl sulfide was dissolved in ethanol and 4 molar equivalents of H 2 O 2Approximately 3% molar equivalent of ammonium heptamolybdate was added as an oxidation catalyst. The next day, the solution was diluted with NaHCO 3 Neutralize with solution and CH 2 Cl 2 The organic layer was evaporated and distilled to give allyl methyl sulfone, which was hydrosilylated with dimethylchlorosilane using Karstedt's catalyst. The product was fluorinated with NaFHF at about 150° C., filtered, distilled twice, and dried over molecular sieves to give pure F1S. 3 Obtained an M.S. [ka]

[0095] DF1S 3 The synthesis of MS proceeded as follows: 3-mercaptopropylmethyldimethoxysilane was dissolved in ethanol and mixed with one (1) molar equivalent of NaOH in water. Then, one (1) molar equivalent of Me 2 SO 4 was added to the mixture and refluxed overnight. The solid was filtered off. The crude product was treated with 4 molar equivalents of H 2 O 2 The product was oxidized with 3% molar equivalents of ammonium heptamolybdate. The solvent was evaporated and 2 molar equivalents of HF in water were added. The product was then purified by CH 2 Cl 2 Extracted and distilled. [ka]

[0096] F1S 3 MN synthesis: Scheme 1 is F1S 3 Drawing the synthesis scheme of MN. [F] is HF, NH 4 Fluorinating agents such as FHF or other fluorinating agents. NH 4 FHF is preferably used as the fluorinating agent for laboratory-scale synthesis. When HF is used, the only by-product is HCl.3 The MN compound is washed from the solid salts with hexane, distilled, dried over CaO, and distilled again. [ka]

[0097] Scheme 2 shows NH as the fluorinating agent. 4 F1S using FHF 3 Drawing a scheme for the synthesis of MN. Karstedt catalyst (Platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex solution, catalog no. 479519, Sigma-Aldrich, St. Louis, MO) results in approximately 3% substitution at the secondary carbon, leading to isoF1S 3 Generates MN. IsoF1S 3 MN is F1S 3 It has a lower boiling point than MN and most of it can be separated by fractional distillation. [ka]

[0098] Scheme 3 shows Cl1S 3 F1S using MN intermediate 3 Draw an alternative, shorter synthetic scheme for MN. 3 MN intermediates are available from Gelest, Inc. (product code SIC2452.0, 11 East Steel Road, Morrisville, PA). 3 The use of the MN intermediate reduces the time involved in the synthesis. [ka]

[0099] Scheme 4 is F1S 3 Another synthesis scheme for MN is depicted. As in Scheme 1, [F] is HF, NH 4A fluorinating agent such as FHF or other fluorinating agents is shown. The use of HF as the fluorinating agent in this synthetic scheme gives no solid by-products, thus eliminating the need for hexane extraction and filtration of solids. The only by-product is HCl. [ka]

[0100] Scheme 5 is F1S 3 Yet another synthetic scheme for MN is depicted. As in Scheme 1, [F] is HF, NH 4 A fluorinating agent such as FHF or other fluorinating agents is indicated. [ka]

[0101] F1S 3 Synthesis of MN: In the preferred route, allyl cyanide is heated at about 100°C with a small amount of Karstedt catalyst. Dimethylchlorosilane is added dropwise and refluxed for 4 hours. After cooling to room temperature, the mixture is fluorinated with 1 molar equivalent of ammonium bifluoride at room temperature. Cold hexane is added to the mixture, the solids are filtered off, and the solvent is evaporated. Calcium oxide is added to the crude product, which is then distilled under a vacuum of 0.4 Torr between 45-55°C to give the desired product, F1S. 3 I got MN.

[0102] F1S 3 Synthesis of ME: [ka] In the preferred route, allyl acetate is mixed with dimethylchlorosilane and a small amount of Karstedt catalyst is added. The mixture is left to react overnight. The next day, the mixture is fluorinated with 0.33 molar equivalents of antimony trifluoride at room temperature overnight with strong stirring. The next day, the solids are filtered off and the product is distilled under a vacuum of 0.3 Torr between 25-30 °C to give the desired product, F1S. 3 Got ME.

[0103] DF1S 3 DN composition: [ka] Bis(cyanopropyl)dichlorosilane was mixed with 2 molar equivalents of aqueous HF at room temperature and left to react overnight. The crude product was extracted with dichloromethane, the solvent was evaporated, and the product was distilled at 165° C. under a vacuum of 0.1 Torr to give the desired product, DF1S. 3 We obtained DN.

[0104] 1S 3 DN composition: [ka] DF1S 3 DN was dissolved in THF and cooled in an ice bath, after which 2 molar equivalents of methylmagnesium bromide were added and the mixture was allowed to react until it slowly reached room temperature. The mixture was quenched with ethanol, the crude product was extracted with dichloromethane, the solvent was evaporated and the product was distilled at 125° C. under a vacuum of 0.2 Torr to give the desired product, 1S. 3 We obtained DN.

[0105] TF1S 3 Synthesis of MN: [ka] Cyanopropyltrichlorosilane was cooled in an ice bath and 4 molar equivalents of aqueous HF was added dropwise. The mixture was left to react for no more than 2 hours. The crude product was extracted with dichloromethane, the solvent was evaporated, and the product was distilled under a vacuum of 0.2 Torr at 25° C. to give the desired product, TF1S. 3 I got MN.

[0106] DPF1S 3 Synthesis of MN: [ka] Bis(isopropyl)cyanopropylchlorosilane was dissolved in THF and cooled in an ice bath, after which 1 molar equivalent of aqueous HF was added dropwise and left to react at room temperature overnight. The next day, the solvent was evaporated and the product was distilled under a vacuum of 60° C. and 0.2 Torr to give the desired product, DPF1S. 3 I got MN.

[0107] DF1S 3 MSO: [ka] DF1S 3 MSO will follow the procedure described in the DF1S 3 Obtained as a by-product of incomplete oxidation during the synthesis of MS. 3 MSO was purified by distillation at 40° C. under a vacuum of 0.1 Torr.

[0108] F1S 3 Synthesis of MA: [ka] In this synthesis, 2 molar equivalents of dimethylallylamine were mixed with 1,1,3,3-tetramethyldisiloxane and a small amount of Karstedt catalyst. The mixture was heated to 100 °C and allowed to react overnight. The next day, the mixture was fluorinated with 0.67 molar equivalents of antimony trifluoride at 150 °C overnight with vigorous stirring. The next day, the solids were filtered off and the product was distilled at 20-25 °C under a vacuum of 0.2 Torr to give the desired product, F1S. 3 He earned his MA.

[0109] F1S 3 Synthesis of MC: [ka] Allyl alcohol was silylated with hexamethyldisilazane using a catalytic amount of aluminum dihydrogen phosphate at 80°C overnight. The intermediate allyloxytrimethylsilane was distilled for purification before hydrosilylation. Hydrosilylation was carried out with 1 molar equivalent of dimethylchlorosilane and a small amount of Karstedt catalyst at 80°C overnight. The next day, the mixture was fluorinated and hydrolyzed with 2 molar equivalents of aqueous hydrofluoric acid at room temperature with vigorous stirring to give (3-hydroxypropyl)dimethylfluorosilane, which was distilled before the next step. The last intermediate was dissolved in hexane, 1 molar equivalent of trimethylamine was added, the mixture was cooled in an ice bath, methyl chloroformate was added dropwise to the mixture, and then reacted at room temperature overnight. The next day, the solid was filtered off, the solvent was evaporated, and the product was distilled at 28°C under a vacuum of 0.2 Torr to give the desired product, F1S. 3 Got MC.

[0110] DF1S 3 Synthesis of MN: [ka] Commercially available 3-cyanopropyldichloromethylsilane (CAS number 1190-16-5; Sigma-Aldrich, St. Louis, MO, US) was fluorinated with ammonium difluoride at room temperature. Cold hexane was then added to the mixture. The solids were filtered off and the solvent was evaporated. Calcium oxide was added to the crude product. The solvent was distilled under a vacuum of 0.4 Torr at 35-45 °C to give the desired product in very high purity (~99.8%) and approximately 90% yield.

[0111] DF1S 2 Synthesis of MN: [ka] Acrylonitrile was mixed with N,N,N',N'-tetramethylethylenediamine and copper(I) oxide in a flask and heated to 60°C. Dichloromethylsilane was then added dropwise and refluxed overnight. After cooling to room temperature, the mixture was distilled under vacuum (43°C, 0.2 Torr) to give the dichloro intermediate (DC1S2 The intermediate was fluorinated with 1.2 molar equivalents of ammonium bifluoride at room temperature or with 1.2 molar equivalents of sodium bifluoride at 130°C. Dichloromethane was then added and the solid was filtered off. The solvent was evaporated and the crude product was distilled under vacuum. Triethylamine and molecular sieves were added to the product and distilled at 25-33°C under a vacuum of 0.1 Torr to give the desired product in very high purity (>99%) and approximately 75% yield.

[0112] 1ND1N synthesis: Scheme 16 depicts a synthesis scheme for 1ND1N. 1ND1N can be synthesized by the addition of sodium (Na), calcium oxide (CaO), or calcium hydride (CaH 2 ) and cannot be dried chemically. [ka]

[0113] Effect of temperature: FIG. 1A shows the reduction in HF production in the salt-in-solvent mixtures containing OS nitriles compared to the autocatalytic HF formation in the carbonate-based control mixtures without OS nitriles at 100° C. Due to the OS moiety, the HF concentration is closest to zero after 20 days of storage at 100° C. HF production and scavenging at lower temperatures was investigated.

[0114] As shown in Figure 3A, HF formation is clearly not autocatalytic at 70°C. Kinetic modeling indicates that the rate constant for HF formation is approximately 4x lower at 70°C than at 100°C.

[0115] The storage stability of the salt mixtures in OS nitrile-containing solvents was then tested at lower temperatures compared to electrolytes without OS nitriles. 3 MN or DF1S 2 When OS nitrile electrolyte containing MN was stored at 30°C for 140 days, no obvious H + No capture of F1S was observed (Figure 3B). 3MN or DF1S 2 When the OS nitrile-containing solvent-based salt mixture containing MN was stored at 45°C, no obvious H + No capture of H was observed (Figure 3C). However, after 141 days, some H + Trapping was seen in the salt mixtures in solvents containing OS nitrile, but at 500 ppm added H 2 All mixtures of O showed a reduction in HF (Figure 3C).

[0116] Compound structure effects: F1S 3 H of OS nitriles other than MN + The effect on capture was also examined. 2 M.N., 1S. 3 MN, F1S 2 MN, DF1S 2 MN, DF1S 3 MN, and TF1S 2 MN included, the result is F1S 3 Figures 4A and 4B show that all the tested OS nitriles exhibited excellent thermal stability at 100 °C. + This indicates that the

[0117] H by OS nitrile + The uptake of H was also compared with other nitriles, including succinonitrile, adiponitrile, and valeronitrile. The results showed that the other nitriles were uptaken at 100 °C with H + (Figure 5A), but the OS nitrile F1S 3 It shows little stabilization and more degradation compared to MN (Figure 5B).

[0118] In addition, the trifluoro structure H + The effect of trifluoroacetate on the capture of nitrile and non-nitrile compounds, TF1S, was evaluated. 2 MN, TF-BN, and TF1S 6 The results showed that all nitriles with trifluoro structures were H at 100°C. + However, it does not capture non-nitrile compounds, such as TF1S 6 M is H+ This shows that the ion exchange rate does not capture the ion exchange rate (Figure 6).

[0119] Carbonate Blend Effects: In this example, the H of the OS nitrile in the carbonate blend + The effect of H on the capture of EC blends with a dielectric constant of 89 was investigated. + Capture is F1S 3 Depends on MN concentration. 1-2% F1S 3 MN, H + No capture of F1S was observed, and the higher the concentration, the 3 MN is H + (Figure 7A). Similar results were obtained with an EC / PC blend with a dielectric constant of 76.9 (data not shown).

[0120] The EC / DEC blend, which has a dielectric constant of 21.8, was next investigated. The results showed that in the EC / DEC blend, which has a dielectric constant significantly lower than that of EC or EC / PC, the absence of OS caused a rapid increase in HF concentration, but the addition of OS significantly decreased the HF concentration (Figure 7B).

[0121] For the high salt EMC mixtures, when no OS nitrile was added, the concentration of HF increased significantly with storage at 100 °C for both the nominal and 500 ppm spiked water control samples (Figure 7C). After 56 days, the samples were too decomposed for NMR analysis. In contrast, the addition of OS reduced the HF concentration by approximately 2%. 3 At MN concentration, H + (Figure 7D). Similar studies have demonstrated that the high salt EMC mixture and DF1S 2 The minimum DF1S required to achieve the same effect in MN 2 MN was 1.6% (data not shown).

[0122] Inhibition of HF formation: Taken together, the data clearly demonstrate that the compositions and methods disclosed herein are effective in preventing alkali metal PF 6The results show that HF ​​production is highly effective in inhibiting unwanted HF production in salt-in-solvent mixtures containing fluorinated salts such as fluorinated salts. See in particular Figure 1A. The control trace shows HF concentrations ranging from 800 to 1400 ppm, without the presence of OS. Figure 1B records the results for mixtures containing 2-10% OS, but no clear HF is shown on the scale of the plot (0-20 ppm). Similarly, see Figure 3A, above. The control trace shows HF concentrations ranging from 800 to 2700 ppm, without OS, with failure (5-18 days).

[0123] See also Figures 4A and 4B. Figure 4A shows the results for a mixture containing 0.13M OS, which showed no evident HF at the scale of the plot (0-10 ppm). Figure 4B shows the results for a mixture containing 1M OS, which showed no evident HF at the scale of the plot (0-1 ppm) over the course of one month.

[0124] See also Figure 5A, which shows the results for mixtures containing nitrile and non-nitrile OS. All mixtures showed no apparent HF on the scale plotted (0-20 ppm).

[0125] FIG. 5B is also important because it clearly shows that the fluorinated OS nitrile compounds disclosed herein are much better at stabilizing these types of salt-in-carbonate mixtures. FIG. 5B shows the relative solubility of several non-OS nitrile compounds (i.e., adiponitrile, succinonitrile, and valeronitrile) versus FlS in both the presence and absence of water. 3 To compare nitrile decomposition using MN, F1S in both conditions (500 ppm water) and without water 3 MNOS was superior in inhibiting the degradation of the mixture.

[0126] Figure 6 shows the results for subjects without OS. These mixtures have HF concentrations >2000 ppm over 21 days. In stark contrast, mixtures containing trifluoro OS nitrile compounds showed zero HF.

[0127] Figure 7A shows that inhibition of HF production was dependent on the concentration of OS: 1% OS had 1800 ppm HF at 50 days; 2% OS had 200-400 ppm HF at 1 month; 5% OS had 40 ppm HF at 50 days; 8% OS had 30 ppm HF at 50 days, 16% OS had 7 ppm HF at 50 days; 20% and 87% OS showed no obvious HF at the scale of the plot (0-1 ppm) at 50 days. As shown in Figure 7B, the control trace without OS had HF concentrations >4000 ppm prior to 20 days. All OS samples (2%, 5%, 10%, 16%), in contrast, supported no obvious HF (0-20 ppm) at 20 days. Figure 7C shows the high salt control, where the HF concentration was 2000 ppm after 20 days. Figure 7D shows the results for the high salt mixture. The control, 0.05% OS, and 0.2% OS mixtures all had HF concentrations >1500 ppm at day 21. In contrast, the 2% OS mixture showed no obvious HF (0–100 ppm).

[0128] These results clearly demonstrate that the mixtures disclosed and claimed herein are effective in stabilizing mixtures of salts in a solvent of a salt, a carbonate solvent, and an organosilicon compound.

Claims

1. 1. A stabilized salt-in-solvent mixture comprising a salt, a carbonate solvent; and an organosilicon compound, wherein the organosilicon compound inhibits decomposition reactions within the salt-in-solvent mixture.

2. The salt is an alkali metal PF 6 2. The stabilized salt-in-solvent mixture of claim 1 which is a salt.

3. The salt is LiPF 6 and NaPF 6 3. The stabilized salt-in-solvent mixture of claim 2, selected from the group consisting of:

4. 3. The stabilized salt-in-solvent mixture of claim 2, wherein the carbonate is a linear carbonate.

5. 3. The stabilized salt-in-solvent mixture of claim 2, wherein the carbonate is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate, ethylene carbonate, propylene carbonate, and gamma-butyrolactone.

6. The organosilicon compound is 【Chemistry 1】 (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b"=0) is "R" and 【Chemistry 2】 selected from the group consisting of: Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 is selected from the group consisting of straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 and straight or branched alkylenyl of C 1-15 and Each "Y" in formula I is independently selected from the group consisting of organic polar groups.

3. The stabilized salt-in-solvent mixture of claim 2, selected from the group consisting of:

7. Each "Y" is independently 【Chemistry 3】 【change】 (wherein the curved bond is C 2-6 (representing an alkylene bridge portion) 7. The stabilized salt-in-solvent mixture of claim 6, wherein the organic polar group is selected from the group consisting of:

8. Each "Y" is independently 【Chemistry 4】 8. The stabilized salt-in-solvent mixture of claim 7, wherein the organic polar group is selected from the group consisting of:

9. The organosilicon compound is 【Chemistry 5】 3. The stabilized salt-in-solvent mixture of claim 2, wherein

10. The organosilicon compound is 【Chemistry 6】 3. The stabilized salt-in-solvent mixture of claim 2, wherein

11. A stabilized salt-in-solvent mixture according to any one of claims 1 to 10 for use in an electrolyte formulation.

12. A stabilized salt mixture in a solvent, comprising an alkali metal PF 6 Salt, carbonate solvent; and 【Chemistry 7】 (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b"=0) is "R" and 【Chemistry 8】 selected from the group consisting of: Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 is selected from the group consisting of straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 and straight or branched alkylenyl of C 1-15 straight or branched chain halo-alkylenyl; and Each "Y" in formula I is independently 【Chemistry 9】 【change】 (wherein the curved bond is C 2-6 (representing an alkylene bridging moiety) and an organosilicon compound selected from the group consisting of: A stabilized salt-in-solvent mixture, wherein the organosilicon compound inhibits decomposition reactions within the salt-in-solvent mixture.

13. 13. The stabilized salt-in-solvent mixture of claim 12, wherein the carbonate is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate, ethylene carbonate, propylene carbonate, and gamma-butyrolactone.

14. Each "Y" is independently 【Chemistry 10】 13. The stabilized salt-in-solvent mixture of claim 12, wherein the organic polar group is selected from the group consisting of:

15. The organosilicon compound is 【Chemistry 11】 13. The stabilized salt-in-solvent mixture of claim 12, wherein

16. The organosilicon compound is 【Chemistry 12】 13. The stabilized salt-in-solvent mixture of claim 12, wherein

17. The salt is LiPF 6 and NaPF 6 13. The stabilized salt-in-solvent mixture of claim 12, selected from the group consisting of:

18. A stabilized salt-in-solvent mixture according to any one of claims 12 to 17 for use in an electrolyte formulation.

19. 1. A method for mitigating degradation of a salt / carbonate solution for use in an electrolyte formulation or formulated electrolyte, the method comprising: 【Chemistry 13】 (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b"=0) is "R" and 【Chemistry 14】 selected from the group consisting of: Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 is selected from the group consisting of straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 and straight or branched alkylenyl of C 1-15 and Each "Y" in formula I is independently 【Chemistry 15】 (wherein the curved bond is C 2-6 (representing an alkylene bridging moiety) adding an organosilicon compound selected from the group consisting of The method, wherein the organosilicon compound inhibits decomposition reactions within the solvent-salt mixture.

20. 1. A stabilized salt-in-solvent mixture comprising an alkali metal PF6 salt, a carbonate solvent; and an organosilicon compound, wherein the mixture has a hydrofluoric acid (HF) concentration of less than about 100 ppm after storage at 100° C. for 20 days.

21. 21. The stabilized salt-in-solvent mixture of claim 20, wherein the concentration of hydrofluoric acid (HF) in the mixture is less than about 20 ppm after storage at 100° C. for 20 days.

22. 21. The stabilized salt-in-solvent mixture of claim 20, wherein the concentration of hydrofluoric acid (HF) in the mixture is less than about 10 ppm after storage at 100° C. for 20 days.

23. 21. The stabilized salt-in-solvent mixture of claim 20, wherein the concentration of hydrofluoric acid (HF) in the mixture is less than about 5 ppm after storage at 100° C. for 20 days.

24. The organosilicon compound is 【Chemistry 16】 (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b"=0) is "R" and 【Chemistry 17】 selected from the group consisting of: Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 is selected from the group consisting of straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 and straight or branched alkylenyl of C 1-15 and Each "Y" in formula I is independently 【Chemistry 18】 (wherein the curved bond is C 2-6 (representing an alkylene bridging moiety) selected from the group consisting of:

21. The stabilized salt-in-solvent mixture of claim 20, wherein the organosilicon compound inhibits decomposition reactions within the salt-in-solvent mixture.

25. 21. The stabilized salt-in-solvent mixture of claim 20, wherein the carbonate is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate, ethylene carbonate, propylene carbonate, and gamma-butyrolactone.

26. The concentration of the organosilicon compound is determined according to the formula: [0010] (In the formula, capacity% OS is the calculated concentration of organosilicon compounds [ppm H 2 O] is the measured concentration of water in the salt mixture in the solvent, and ρ OS is the density of the organosilicon compound, and ρ sol is the density of the solvent mixture, and M OS is the molecular weight of the organosilicon compound, and M H2O is the molecular weight of water) 21. The stabilized salt-in-solvent mixture of claim 20, calculated using:

27. The organosilicon compound is 【Chemistry 19】 (In the formula, "a" is an integer from 1 to 4; "b" is an integer from 0 to (3×a); "Z" (absent if "b"=0) is "R" and 【Chemistry 20】 selected from the group consisting of: Each "R" is independently halogen, C 1-6 Straight or branched chain alkyl, alkenyl, or alkynyl of C 1-6 is selected from the group consisting of straight or branched chain halo-alkyl, halo-alkenyl, or halo-alkynyl; Each "Sp" in formulas I and II is independently C 1-15 and straight or branched alkylenyl of C 1-15 and Each "Y" in formula I is independently 【Chemistry 21】 (wherein the curved bond is C 2-6 (representing an alkylene bridging moiety) selected from the group consisting of:

21. The stabilized salt-in-solvent mixture of claim 20, wherein the organosilicon compound inhibits decomposition reactions within the salt-in-solvent mixture.

28. 28. The stabilized salt-in-solvent mixture of claim 27, wherein the carbonate is selected from the group consisting of ethyl methyl carbonate, dimethyl carbonate, and diethyl carbonate, ethylene carbonate, propylene carbonate, and gamma-butyrolactone.

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