Sodium salts having borate or aluminate anions

Abstract

TIFF2026511325000018.tif47154 A compound of formula (I) or formula (II), where (I)(II)X is Al or B, and R 1 In each case, the substituents are independently of the two R 1 The groups may be bonded in such a way that they form a ring, provided that at least one R is present. 1 This refers to a partially fluorinated linear or branched carbon atom, in which one or more non-adjacent and non-terminal carbon atoms other than the carbon atom bonded to the oxygen in XO may be substituted with oxygen. 1-20 The alkyl group is the fluorinated C 1-20 The alkyl group contains at least one group of the formula -CF2H or -CFH2, and R2 is independently a divalent organic group in each case. Compounds of formula (I) or formula (II) can be used as electrolytes in sodium batteries or sodium-ion batteries.

Description

[Background technology]

[0001] Lithium batteries and lithium-ion batteries, which contain lithium salts, have been the subject of extensive research. However, the scarcity of lithium is a drawback. Therefore, batteries containing more abundant metals such as sodium, magnesium, and potassium have been studied.

[0002] D. Ould et al, “Sodium Borates: Expanding the Electrolyte Selection for Sodium-Ion Batteries”, Angew. Chem. Int. Ed. 2022, 61, e202202133 discloses sodium alkoxyborate salts for sodium-ion batteries. WO2021 / 138370 discloses lithium metal batteries having an ionic liquid electrolyte containing a sodium additive.

[0003] EP3783720 discloses an electrolyte solution containing a sodium or potassium bis(oxalato)borate salt and an organic solvent containing pyrrolidone and / or a phosphate compound.

[0004] US 2021 / 036358 discloses an SO2-based electrolyte for rechargeable battery cells comprising a conductive salt of the following formula (I), where M is selected from alkali metals, alkaline earth metals, Group 12 metals, and aluminum. [ka]

[0005] US2018 / 019498 discloses a non-aqueous electrolyte for secondary batteries comprising at least one of the following: boric acid esters, acid anhydrides, cyclic carbonate esters having unsaturated bonds, cyclic carbonate esters having halogen atoms, cyclic sulfonic acid esters, and amines having acetoacetyl groups. [Overview of the project]

[0006] The present disclosure provides a compound of the following formula (II).

Chemical formula

[0007] Optionally, at least one R 2 is a group of the following formula (III),

Chemical formula

[0008] Optionally, Ar 1 is unsubstituted or substituted 1,2-phenylene.

[0009] By choice, each R 2 This is the base of equation (III).

[0010] This disclosure provides compounds of the following formula (I). [ka] In the formula, X is either Al or B, R 1 These are independent substituents in each case, and the two R 1 The groups may be bonded in such a way that they form a ring. However, at least one R 1 In XO, one or more non-adjacent non-terminal carbon atoms, excluding the carbon atom bonded to the oxygen, may be substituted with oxygen, and fluorinated C 1-20 A partially fluorinated linear or branched C group containing at least one alkyl group having the structural formula -CF2H or -CFH2. 1-20 The condition is that it must be an alkyl group.

[0011] By choice, each R 1 In XO, one or more non-adjacent non-terminal carbon atoms, excluding the carbon atom bonded to the oxygen, may be substituted with oxygen, and fluorinated carbon may be present. 1-20 A partially fluorinated linear or branched C group containing at least one alkyl group having the structural formula -CF2H or -CFH2. 1-20 It is an alkyl group.

[0012] This disclosure provides an electrolyte comprising a compound of formula (I) or formula (II) and one or more solvents.

[0013] By arbitrary selection, one or more of the above solvents are C 2-10 Alkylene carbonate and di(C) 1-10 It contains at least one alkyl carbonate.

[0014] Optionally, the electrolyte contains at least 1 mole of sodium cations per 10 moles of solvent.

[0015] By option, the concentration of the compound of formula (I) or formula (II) is at least 0.25 mol / liter.

[0016] This disclosure provides a battery comprising an anode, a cathode, and an electrolyte disposed between the anode and the cathode, the electrolyte comprising a compound of formula (I) or formula (II).

[0017] Optionally, the battery contains a total solvent of 10 moles or less per mole of Na+. [Brief explanation of the drawing]

[0018] [Figure 1] This is a schematic diagram of a battery containing a compound according to the present disclosure embodiment. [Figure 2] This shows the circuit used to measure the impedance of an electrolyte. [Figure 3A] The Nyquist plots of cells including Compound Example 1 and Compound Example 2 according to some embodiments of the present disclosure are shown. [Figure 3B] A magnified view of the Nyquist plot in Figure 3A is shown. [Modes for carrying out the invention]

[0019] Unless the context clearly requires a different interpretation, in this specification and the claims, words such as “comprise” and “comprising” shall be interpreted in a comprehensive sense, meaning “including, but not limited to,” rather than in an exclusive or exhaustive sense. Furthermore, when used in this application, “herein,” “above,” “below,” and similar words refer to the entire application and not to any particular part. Where the context allows, singular or plural words in “detailed description” may also include plural or singular forms, respectively. When the word “or” lists two or more items, it encompasses all of the following meanings: any item in the list, all items in the list, and any combination thereof in the list. Where used in this application, when a layer is referred to as being “over” another layer, it means that the layer may be in direct contact with the other layer or through one or more intermediate layers. On the other hand, when a layer is referred to as being “on” another layer, it means that the layer is in direct contact with the other layer. Where referring to an element of the periodic table, it also includes all isotopes of that element.

[0020] The teachings of the technology provided herein can be applied to other systems and are not limited to the systems described below. The elements and operations of the various embodiments described below can be combined to provide further implementations of the technology. Alternative implementations of this technology may include not only those that add elements to the implementations described below, but also those that reduce the elements.

[0021] In light of the detailed description below, other modifications may be made to the Art in addition to those described here. While this description provides specific examples and best-case modes of the Art, the Art can be implemented in a variety of ways, even if the description is detailed. As stated above, terms used in describing specific features or aspects of the Art should not be interpreted as being redefined in this specification to be limited to the specific characteristics, features, or aspects of the Art to which the terms relate. In general, terms used in the following claims should not be interpreted as limiting the technical scope to the specific embodiments disclosed herein, unless such terms are clearly defined in the detailed description of this invention. Therefore, the actual technical scope of the Art is not limited to the disclosed embodiments, but encompasses all equivalent means of carrying out or implementing the Art under the claims.

[0022] To reduce the number of claims, certain aspects of the present technology are shown below in the form of specific claims, although the applicant may conceive of various aspects of the present technology in any number of claim forms.

[0023] The following description includes many specific details for illustrative purposes to ensure a thorough understanding of the implementation of the disclosed technology. However, it will be apparent to those skilled in the art that the disclosed embodiments can be implemented without using some of these specific details.

[0024] Figure 1 shows a battery. This battery may be a sodium battery or a sodium-ion battery. This battery is preferably a secondary battery (rechargeable battery).

[0025] The battery comprises an anode current collector 101 in contact with the anode 103 on its surface, a cathode current collector 109 in contact with the cathode 107, and a layer 105 containing or consisting of the electrolyte described herein, disposed between the anode and the cathode.

[0026] In some embodiments, layer 105 is a gel layer comprising a polymer, a solvent, and a compound of formula (I).

[0027] In some embodiments, layer 105 is a porous separator comprising an electrolyte described herein absorbed into the porous separator.

[0028] In the case of a sodium-ion battery, the anode contains an active material such as graphite for absorbing metal ions.

[0029] In the case of a sodium battery, the anode 103 is a layer of sodium that forms above the anode current collector during battery charging and is peeled off during discharge.

[0030] The cathode can be selected from any cathode known to those skilled in the art.

[0031] The anode and cathode current collectors may be one or more layers of any suitable conductive material known to those skilled in the art, such as a metal or metal alloy, such as aluminum or copper.

[0032] For simplicity, Figure 1 shows a battery in which the anode and cathode are separated only by a layer containing or consisting of an electrolyte; however, it will be understood that during use, a solid electrolyte interface is typically formed on the anode surface.

[0033] In other embodiments, one or more additional layers may be placed between the anode and the electrolyte and / or between the cathode and the electrolyte.

[0034] The batteries described herein, or battery packs comprising multiple batteries described herein, can be used without limitation to supply power to electric vehicles or stationary objects.

[0035] Compound of formula (I) Equation (I) is as follows: [ka] X is either Al or B.

[0036] R 1 These are substituents in each case independently, and the two R 1 The groups may be bonded in such a way that they form a ring.

[0037] Preferably, each R 1 Each of them operates independently. Linear, branched, or cyclic carbon atoms, where one or more non-adjacent non-terminal carbon atoms, excluding the carbon atom bonded to the oxygen in XO, may be substituted with oxygen, and one or more hydrogen atoms may be substituted with fluorine. 1-20 Alkyl, C replaced by arbitrary selection 6-20 Aryl or C 5-20 Heteroaryls, and C atoms excluding the C atom bonded to the O bond in borate 1-20 One or more non-terminal carbon atoms of the alkylene may be substituted with oxygen. 1-20 One or more H atoms of the alkylene may be substituted with F, and C 6-20 Aryl or C 5-20 The heteroaryl may be unsubstituted or substituted, C 1-20 Alkylene-C 6-20 Aryl or C 1-20 Alkylene-C 5-20 Selected from heteroaryls.

[0038] C 6-20 Aryl or C 5-20 If substituents are present in the heteroaryl, these substituents are preferably, and each independently, substituent R 5 Selected from, here, R 5 In each case, independently, F and C 1-12 It is alkyl, and here this C 1-12 One or more non-terminal carbon atoms of the alkyl group are O, S, or NR. 4 CO, COO, or CONR4 It may also be replaced with, where R 4 In each case, independently, C 1-12 It is a hydrocarbon group, and this C 1-12 One or more H atoms of the alkyl group may be substituted with F.

[0039] In this specification, "non-terminal carbon atom" means one methyl group at the end of a linear alkyl chain, or one methyl group at the end of each branched alkyl chain.

[0040] C as described in any part of this specification 1-12 The hydrocarbon group is preferably C 1-12 Alkyl, phenyl, and one or more C 1-6 Selected from alkyl-substituted phenyl compounds.

[0041] At least two R 1 If the groups are not bonded, preferably each R 1 In each case, independently, one or more non-adjacent non-terminal carbon atoms, excluding the carbon atom bonded to the oxygen of XO, may be substituted with oxygen, and the fluorinated carbon 1-20 A partially fluorinated linear or branched C group containing at least one alkyl group having the structural formula -CF2H or -CFH2. 1-20 It is an alkyl group.

[0042] In some embodiments, two pairs of R 1 A compound with a bonded group, having formula (I), has the following formula (II). [ka]

[0043] R 2 In each case, these are independently divalent organic groups.

[0044] Preferably, R 2 teeth, Non-substitutive or substituted C6-20 Allirene or C 5-20 Heterorialene, In a borate, one or more non-adjacent carbon atoms may be substituted with oxygen, and one or more hydrogen atoms may be substituted with fluorine, in an unsubstituted or substituted carbon. 1-20 Alkilen, C, excluding the carbon atom bonded to the oxygen in borate 1-20 One or more non-adjacent carbon atoms of the alkylene may be substituted with oxygen atoms. 1-20 The alkylene may be unsubstituted or substituted, and C 6-20 Allirene or C 5-20 Whether heteroarylene is substituted or unsubstituted, C 1-20 Alkylene-C 6-20 Allirene or C 1-20 Alkylene-C 5-20 Selected from heteroarylenes.

[0045] C 6-20 Allirene or C 5-20 Heteroarylene may be unsubstituted or substituted with one or more substituents. If substituents are present, preferred substituents are those described above for R 5 Selected from.

[0046] R 2 Preferably, Ar 1 Here, Ar 1 In each case, C is replaced by an independent, arbitrary choice. 6-20 Allirene or C 5-20 A heteroarylene group, for example, 1,2-phenylene, which can be unsubstituted or substituted with one or more substituents; formula Ar 1 -Ar 1 The biarylene group is selected from, for example, 2,2'-bonded biphenylene, which may be unsubstituted or substituted with one or more substituents; ethylene; propylene; and the group of formula (III) below. [ka] In the formula, R 3In each case, H, F, or C in which one or more H atoms can be substituted by F 1-6 is alkyl, and Ar 1 is C 6-20 is an arylene group, preferably unsubstituted or substituted 1,2-phenylene.

[0047] In a preferred embodiment, at least one R 3 , optionally each R 3 is C 1-6 is a perfluoroalkyl group.

[0048] Preferably, each Ar in formula (I) 1 is phenylene, more preferably unsubstituted or 1,2-bonded phenylene substituted with one or more substituents.

[0049] When a substituent is present on Ar 1 , this substituent is preferably selected independently from the above-mentioned R 5

[0050] The compound of formula (I) or formula (II) can be produced by reacting the compound of formula (IV) with either the compound of formula (Va) or formula (Vb) when no R 1 group is bonded, or with the compound of formula (VIa), (VIb) or (VIc) when it is a compound of formula (II).

Chemical formula

[0051] The compound of formula (Va) may be a primary, secondary or tertiary alcohol.

[0052] The compound of formula (Vb) may be an aldehyde or a ketone.

[0053] ​Exemplary compounds of formula (IV) include, but are not limited to, sodium aluminum hydride (NaAlH4) and sodium borohydride (NaBH4).

[0054] Solvent An electrolyte containing one or more solvents and a compound of formula (I) or formula (II) is C 2-10 Alkylene carbonate, di(C 1-10 alkyl) carbonate, for example, propylene carbonate, ethylene carbonate, dimethyl carbonate, diethyl carbonate and their fluorinated derivatives; linear, branched or cyclic compounds containing two or more ether groups, for example, 1,3-dioxolane, 2,5-dimethoxytetrahydrofuran, glyme (dimethoxyethane), diglyme, triglyme and tetraglyme; diethylene glycol diethyl ether; succinonitrile; cyclic lactones and mixtures thereof, and may contain one or more solvents selected therefrom.

[0055] Optionally, the ratio of the number of moles of the solvent to the number of moles of Na+ in the electrolyte is 20:1 or less, optionally 15:1 or less, or 10:1 or less.

[0056] Polymer The electrolyte described herein may contain a polymer, and in that case, the electrolyte may be a gel.

[0057] This polymer may be selected from any known ion-conducting polymer, including, but is not limited to, poly(alkylene oxides), e.g., poly(ethylene oxide) and poly(propylene oxide); fluorinated polymers such as PVDF and PVDF-HFP; PMMA; polyacrylonitrile; polycarbonate; polyethylene; polypropylene; poly(vinyl methyl ketone); polyvinylpyrrolidone; polyetheretherketone; polyisoprene; polybutadiene; polystyrene-block-polyisoprene-block-polystyrene; poly(1-vinylpyrrolidone-co-vinyl acetate); polystyrene-block-polybutadiene-block-polystyrene; polystyrene-block-poly(ethylene oxide-block)-polystyrene; and copolymers and mixtures thereof.

[0058] This polymer is preferably a neutral polymer, i.e., a polymer not substituted with ionic groups, and in particular, it is preferable that it is not a single-ionic conductive polymer containing a negative group. [Examples]

[0059] Compound Example 1 [ka]

[0060] The reaction was carried out under a nitrogen atmosphere. NaBH4 (151 mg, 4 mmol, 0.34 M) in anhydrous tetrahydrofuran solution was added dropwise to a solution of (1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)phenol (2.08 g, 8 mmol) in 12 mL of tetrahydrofuran at room temperature. The mixture was then stirred at room temperature for 3 hours, followed by stirring at 65°C for another 3 hours. Subsequently, NaBH4 (55 mg, 1.45 mmol, 0.72 M) in THF solution was added dropwise. The reaction mixture was then stirred at room temperature overnight. After the reaction was complete, propylene carbonate (1.4 mL, 16 mmol) was added. The excess solvent was drained at 30°C (3.3 × 10⁻⁶). -2The material was removed under reduced pressure (mbar) for 3 hours, yielding a viscous, transparent oily substance.

[0061] THF-d8: δ (ppm), 1 ¹H NMR (600MHz): 1.37 (d, CH3, derived from propylene carbonate, 20.7H), 3.96 (m, CH, derived from propylene carbonate, 6.7H), 4.50 (t, CH, derived from propylene carbonate, 6.7H), 4.80 (m, CH, derived from propylene carbonate, 6.1H), 6.73 (m, 4H), 7.16 (td, J=7.6Hz, J=1.7Hz, 2H), 7.33 (d, J=7.8Hz, 2H).

[0062] From the integrated values ​​of the NMR peaks, it was calculated that for every two molecules of (1,1,1,3,3,3-hexafluoro-2-hydroxypropan-2-yl)phenol corresponding to one sodium cation, 6.70 molecules of propylene carbonate remain as residual solvent per sodium cation.

[0063] Compound Example 2 [ka]

[0064] The reaction was carried out under a nitrogen atmosphere. A solution of NaBH4 (203 mg, 5.37 mmol, 0.45 M) in anhydrous tetrahydrofuran was added dropwise at room temperature to a solution of 2,2,3,3,4,4,5,5-octafluoropentan-1-ol (OFP) (3 mL, 21.5 mmol) dissolved in 12 mL of tetrahydrofuran. The mixture was stirred at room temperature for 1 hour, then stirred at 65°C for 4 hours. The reaction mixture was further stirred at room temperature overnight. After the reaction was complete, propylene carbonate (0.68 mL, 8.06 mmol) was added. The excess solvent was then drained at 30°C (3.3 × 10⁻⁶). -2 The material was removed under reduced pressure (mbar) for 3 hours to obtain a viscous, transparent oily substance. Propylene carbonate was then added to obtain a stable, transparent liquid.

[0065] THF-d8: δ (ppm) medium 1 ¹H NMR (600MHz): 1.39 (d, CH3, derived from propylene carbonate, 14.7H), 3.90 (t, J=15.01Hz, 7.7H), 3.97 (m, CH, derived from propylene carbonate, 7.8H), 4.50 (t, CH, derived from propylene carbonate, 4.7H), 4.80 (m, CH, derived from propylene carbonate, 4.2H), 6.62 (tt, J=51.4Hz, J=5.8Hz, 4H).

[0066] From the integrated values ​​of the NMR peaks, it was calculated that for each sodium cation in the product, there are 4.80 molecules of propylene carbonate present as a residual solvent for each sodium cation, corresponding to 4 molecules of octafluoropentyloxy ligands.

[0067] Cell formation The 2032 coin cells were fabricated in an MBraun glove box, which was strictly dried, oxygen-free, and filled with argon gas, using a case purchased from Cambridge Energy Solutions.

[0068] A stainless steel spacer was inserted into the bottom of the coin cell, followed by a fluorosilicone stencil (purchased from Silex Silicones). This stencil was a 15.5 mm diameter disc with a 5 mm diameter circular hole cut into its center (the stencil thickness with the cell pressed in was 360 μm). 30 μL of electrolyte was filled into this hole. The stainless steel spacer, wave spring, and top of the coin cell were then placed on top of the stencil in that order. Finally, the coin cell was pressed into place.

[0069] The electrolyte formulation used to form the coin cell contained either Compound Example 1, Compound Example 2, Comparative Compound 1, or Comparative Compound 2. [ka]

[0070] Electrochemical impedance spectroscopy (EIS) EIS measurements of coin cells were performed at room temperature using a potentiostat (Interface 1010E, Gamry Instruments).

[0071] The EIS spectrum was acquired with an amplitude of 5 mV over a frequency range from 1 Hz to 1 MHz.

[0072] The ionic conductivity was calculated using the following formula.

number

[0073] To measure the impedance, the Nyquist plots of each cell were fitted to the equivalent circuit shown in Figure 2, and the impedance of resistance 1 was adopted as the ionic resistance of the electrolyte in the system.

[0074] Resistance 1 corresponds to the intersection of the first semicircle with the x-axis on the x-axis of the Nyquist plot.

[0075] The Nyquist plots for compound examples 1 and 2 are shown in Figure 3A. Enlarged plots are shown in Figure 3B.

[0076] The ionic conductivity is shown in Table 1. [Table 1]

[0077] As shown in Table 1, surprisingly, Compound Example 1 has a significantly higher ionic conductivity than Comparative Compound 1, and despite the fact that the sodium cation size of Compound Examples 1 and 2 is significantly larger than the lithium cation size of Comparative Compounds 1 and 2, Compound Example 2 has an ionic conductivity comparable to that of Comparative Compound 2.

[0078] Furthermore, the inventors have surprisingly discovered that while D. Ould et al. (cited above) disclose that Na[B(OCH2(CF2)2CF3)4] is poorly soluble in a 1:1 mixed solvent of ethylene carbonate and diethyl carbonate, Compound Example 1 can be dissolved in propylene carbonate, allowing for the creation of a high-concentration solution.

Claims

1. The following compound of formula (II): 【Chemistry 1】 In the formula, X is Al or B, and in each case R ２ However, they became independent, Non-substitutive or substituted C ６－２０ Arirene or C ５－２０ Heterarylene and In the borate, one or more non-adjacent carbon atoms, excluding the carbon atom bonded to the oxygen, may be substituted with oxygen, and one or more hydrogen atoms may be substituted with fluorine, thus the carbon is either unsubstituted or substituted. １－２０ Alkilen and, The C excluding the C atom bonded to O of the borate １－２０ One or more of the non-adjacent C atoms in the alkylene may be substituted with O, and the C １－２０ -alkylene may be unsubstituted or substituted, and the C ６－２０ -arylene may be substituted or unsubstituted, and the C １－２０ -alkylene-C ６－２０ -arylene or C １－２０ -alkylene-C ５－２０ -heteroarylene, and is a divalent organic group selected from, a compound.

2. at least one R ２ The compound is the base of the following formula (III), 【Chemistry 2】 In the formula, R ３ In each case, is H or a substituent, and Ar １ C is either unsubstituted or substituted. ６－２０ Arylene group or C ５－２０ The compound according to claim 1, wherein the group is a heteroarylene group.

3. Ar １ The compound according to claim 2, wherein is unsubstituted or substituted 1,2-phenylene.

4. Each R ２ The compound according to claim 2 or 3, wherein is a group of formula (III).

5. The following compound of formula (I): 【Transformation 3】 In the formula, X is either Al or B. R １ In each case, are independent substituents and two R １ The groups may be bonded to form a ring, provided that at least one R １ However, partially fluorinated linear or branched C １－２０ It is an alkyl group, and the C １－２０ In the alkyl group, one or more non-adjacent and non-terminal carbon atoms, excluding the carbon atom bonded to the oxygen in X-O, may be substituted with oxygen, and the fluorinated carbon １－２０ The alkyl group is -CF ２ H or -CFH ２ The condition is that the formula contains at least one base, compound.

6. Each R １ However, partially fluorinated linear or branched C １－２０ It is an alkyl group, and the C １－２０ In the alkyl group, one or more non-adjacent and non-terminal carbon atoms, excluding the carbon atom bonded to the oxygen in X-O, may be substituted with oxygen, and the fluorinated carbon １－２０ The alkyl group is -CF ２ H or -CFH ２ The compound according to claim 5, comprising at least one group of the formula.

7. An electrolyte comprising the compound described in any one of the preceding claims and one or more solvents.

8. The one or more solvents mentioned above are C ２－１０ Alkylene carbonate and di(C) １－１０ The electrolyte according to claim 7, comprising at least one alkyl carbonate.

9. The electrolyte according to claim 7 or 8, wherein the electrolyte contains at least 1 mole of sodium cation per 10 moles of solvent.

10. The electrolyte according to any one of claims 7 to 9, wherein the concentration of the compound of formula (I) or formula (II) is at least 0.25 mol / liter.

11. A battery comprising an anode, a cathode, and an electrolyte according to any one of claims 7 to 10, disposed between the anode and the cathode.

12. The battery according to claim 11, wherein the battery comprises a total solvent of 10 moles or less per mole of Na+.

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