CN114230590A

CN114230590A - Boron trifluoride salt electrolyte containing unsaturated heterocycle and preparation and application thereof

Info

Publication number: CN114230590A
Application number: CN202010940522.5A
Authority: CN
Inventors: 俞会根; 杨萌
Original assignee: Beijing WeLion New Energy Technology Co ltd
Current assignee: Beijing WeLion New Energy Technology Co ltd
Priority date: 2020-09-09
Filing date: 2020-09-09
Publication date: 2022-03-25

Abstract

The invention relates to an electrolyte of boron trifluoride salts containing unsaturated heterocycles, and preparation and application thereof, wherein the electrolyte comprises boron trifluoride salts represented by the following general formula I: r' represents an unsaturated heterocyclic ring which contains at least one heteroatom and also contains at least one unsaturated bond; the heteroatom is selected from S, N, O, P, Se, Ca, Al, B or Si; m is a metal cation; e₁、E₂Independently is nothing, a group, a chain structure or a structure containing a ring; r is a substituent, any one H on the substituent ring can be substituted by the substituent, and the substituent can be substituted by one H and can also be substituted by two or more H, if two or more H are substituted, the substituent can be substituted by two or more HThe substituents may be the same or different. The electrolyte in the present application creatively combines two-OBF₃M is complexed in one compound, and preferably OBF₃M is bonded to the carbon atom C. The boron organic compound can be used as electrolyte salt and additive, and has good effect.

Description

Boron trifluoride salt electrolyte containing unsaturated heterocycle and preparation and application thereof

Technical Field

The invention relates to the technical field of batteries, in particular to a boron trifluoride salt electrolyte containing unsaturated heterocycles and preparation and application thereof.

Background

The electrolyte is an important and necessary component of the secondary battery, the lithium/sodium battery has the advantages of high energy density, high voltage, multiple cycle times, long storage time and the like, and since commercialization, the lithium/sodium battery is widely applied to various aspects such as electric vehicles, energy storage power stations, unmanned aerial vehicles, portable equipment and the like, and no matter which application direction, the energy density and the cycle performance of the battery are urgently required to be improved on the premise of ensuring the safety of the battery.

The lithium/sodium battery mainly comprises a positive electrode, a negative electrode, an electrolyte and a diaphragm, and the improvement of the energy density of the battery is to improve the working voltage and the discharge capacity of the battery, namely to use a high-voltage high-capacity positive electrode material and a low-voltage high-capacity negative electrode material; the improvement of the cycle performance of the battery is mainly to improve the stability of an interface layer formed between an electrolyte and a positive electrode and a negative electrode.

Taking a lithium battery as an example, in the current lithium battery, commonly used positive electrode materials include high voltage Lithium Cobaltate (LCO), high nickel ternary (NCM811, NCM622, NCM532, and NCA), Lithium Nickel Manganese Oxide (LNMO), lithium rich (Li-rich), and the like; common negative electrode materials include metallic lithium, graphite, silicon carbon, silicon oxycarbide, and the like; the commonly used separator is mainly a porous film of polyethylene or polypropylene. The electrolyte comprises a liquid electrolyte and a solid electrolyte, wherein the liquid electrolyte is a mixture of lithium salt and a non-aqueous solvent and is divided into a carbonate electrolyte and an ether electrolyte according to the type of the solvent; the solid electrolyte mainly comprises a polymer electrolyte, an inorganic oxide electrolyte and a sulfide electrolyte. The sulfide electrolyte is extremely sensitive to air, has a narrow electrochemical window and is unstable to the anode; the oxide electrolyte has too high hardness and high brittleness; the electrochemical window of the polymer electrolyte is not wide, the conductivity is low, and the ion transference number is low. Therefore, most of the currently used electrolytes are liquid electrolytes, and a few of them use polymer electrolytes. In addition, when the high-voltage anode and the low-voltage cathode are matched with a conventional liquid electrolyte, part of lithium ions coming out of the anode are consumed in the first cycle, and a passivation layer which only conducts ions and does not conduct electrons is formed on the surfaces of the anode particles and the cathode particles. Sodium ion batteries also suffer from similar problems.

Additives such as fluoroethylene carbonate and vinylene carbonate are often added into the electrolyte to improve the battery performance, but the conventional electrolyte additives usually do not contain dissociable ions and only consume ions of the positive electrode to form a surface passivation layer, so that the first-effect and specific discharge capacity are low. If the added salt/additive can form a passivation layer which is conductive to ions and good in stability on the surface of the electrode, the liquid electrolyte and the polymer electrolyte with narrow electrochemical windows can be applied to a high-voltage battery system. In addition, the price of the lithium/sodium salt which is commercially available at present is very high, so that the cost of the whole battery is higher, and if a new lithium/sodium salt or other salts which replace the lithium/sodium salt in the prior art can achieve both high performance and low cost, the price of the battery is necessarily greatly reduced.

One of the groups of the Applicant has been working on compositions containing-OBF obtained by substitution of one hydroxyl group-OH₃Compounds of the M group were studied. Due to-OBF₃Is a strongly polar group capable of forming a salt structure with a cation, thus, -OBF₃M has a strong sense of presence in one molecular structure, which may change the properties of the entire molecular structure. In the prior art, BF-containing samples were also only investigated by very individual researchers₃Compounds of the group were studied sporadically and all contained only one BF₃The group is researched, at present, no great results are obtained, and no results of industrial application are found; the prior art is directed to-O-BF₃M groups were studied, not to mention the two-OBF groups₃Studies of the M group are published. This is because-OBF₃M is strongly present, if-OBF is added to the molecule₃The number of M may vary unpredictably in the overall properties of the overall molecular structure, and thus research teams may be able to conduct procedures involving two or more-OBFs₃M study, the resistance will be largeIncreased, potentially very large time and economic costs, and unpredictable results, so the research team has been on the inclusion of only one-OBF₃M was studied. Even if the pair contains one-OBF₃M is researched, and due to the fact that the prior art is few, the reference value is small, and the research on two groups is not from any reference source. The present research team also unexpectedly found-OBF containing a dihydroxy substitution in occasional studies₃M organic matter is applied to lithium/sodium batteries in liquid electrolyte and solid electrolyte, and the prepared batteries have excellent performance and surprising effect through tests, so that a specially established team carries out special research on double-substituted-OBF₃M, and obtains better research results.

More importantly, the present application is directed to-OBF₃The structure of M attached to a heterocycle, especially an unsaturated heterocycle, was independently studied. This is because chemical properties such as electrical properties of hetero atoms, unsaturated bonds, and the like are also peculiar, and when they exist on a ring, they affect chemical and physical properties of the whole ring, and they are substantially different from a carbon ring, an aromatic ring, a chain structure, and the like, and hence the relationship or the deductibility between them is uncertain. Thus, the linkage of-OBF to the unsaturated heterocycle₃M, it may have effects different from those of other structures, especially the connection of two-OBFs₃M, it may have a more unexpected superior effect. The subject of the present application is therefore identified as a direct or indirect linkage of-O-BF to an unsaturated heterocycle₃M, thereby more specifically determining-O-BF₃Specific case when M is attached to an unsaturated heterocycle.

Disclosure of Invention

The invention provides a boron trifluoride salt electrolyte containing unsaturated heterocycle, and preparation and application thereof, aiming at overcoming the defects in the prior art.

The purpose of the invention is realized by the following technical scheme:

an aspect of the present invention is to provide an unsaturated heterocycle-containing boron trifluoride salt electrolyte including an unsaturated heterocycle-containing boron trifluoride salt represented by the following general formula I:

in the general formula I, R' represents an unsaturated heterocyclic ring, and the unsaturated heterocyclic ring contains at least one heteroatom and at least one unsaturated bond; the heteroatom is selected from S, N, O, P, Se, Ca, Al, B or Si; m is a metal cation; e₁、E₂Independently is nothing, a group, a chain structure or a structure containing a ring; r is a substituent, any one H on the representative ring can be substituted by the substituent, and the substituent can be substituted by one H and can also be substituted by two or more H, if two or more H are substituted, the substituents can be the same or different, that is, each H can be substituted by the substituent defined in any one of R.

Preferably, in the general formula I, the unsaturated heterocycle is a three-to twenty-membered ring; the unsaturated bond is a double bond; two of the general formula I-OBF₃M may be ortho, meta, spaced 2 atoms apart, or spaced more than two atoms apart.

Preferably, in the formula I, with-OBF₃The atom to which M is attached is a carbon atom C; more preferably, in two-OBF of formula I₃In M, at least one is attached to a carbon atom other than the carbonyl carbon, which includes-C ═ O or-C ═ S.

Preferably, the heteroatom is selected from S, N, O, P or Si.

Preferably, H on any one C in said formula I may be independently substituted by halogen, i.e. ring, substituent, E₁、E₂Etc., and therefore, in the definitions described below, there are some technical features that do not specifically describe the substitution of any one C H by a halogen.

Preferably, the substituent R is selected from H, a halogen atom, a carbonyl group, an ester group, an aldehyde group, an ether oxy group, an ether thio group, ═ O, ═ S, and,

Nitro, cyano, amino, amide, sulfonamide, sulfoalkane, sulfonic acid group, hydrazino, diazo, alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, alkenylalkynyl, heteroalkynyl, cyclic substituent, salt substituent, and a group in which any one hydrogen H in these groups is substituted with a halogen atom; wherein the ester group includes carboxylate, carbonate, sulfonate and phosphate, R₂、R₃Independently is H, alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, alkenynyl, heteroalkynynyl, or ring.

Preferably, any one of the structures of heteroalkyl, heteroalkenyl, heteroalkynyl, and heteroalkynyl contains at least one of the non-carbon atoms selected from halogen, S, N, O, P, Se, Ca, Al, B, or Si; the ring substituent comprises a ternary-eight-membered ring and a polycyclic ring formed by at least two monocyclic rings; such salt substituents include, but are not limited to, sulfate (e.g., lithium sulfate, sodium sulfate, potassium sulfate), sulfonate (e.g., lithium sulfonate), sulfonimide salt (e.g., lithium sulfonimide), carbonate, carboxylate (e.g., lithium carboxylate, sodium, potassium, etc.), thioether salt (e.g., -SLi), oxoether salt (e.g., -OLi), ammonium salt (e.g., -NLi), hydrochloride, nitrate, azide, silicate, phosphate.

Preferably, the carbonyl group is-R₁₀COR₁₁The ester group is-R₁₂COOR₁₃、-R₁₂OCOR₁₇、-R₁₂SO₂OR₁₃、R₁₂O-CO-OR₁₃Or

The ether oxygen radical is-R₁₄OR₁₅The etherthio radical is-R₁₄SR₁₅(ii) a The sulfoalkane is-R₁₈SO₂R₁₉Amino is ═ N-R₂₀、

or-CH ═ N-R₂₄Amide is

Sulfonamide group of

Wherein R is₂、R₃、R₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₅、R₁₆、R₁₇、R₁₈、R₁₉、R₂₀、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₈、R₂₉、R₃₀、R₃₁、R₃₂、R₃₃、R₃₄、R₃₅Independently is alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, or ring, heteroalkane/alkene/alkynyl being an alkane/alkene/alkynyl having at least one heteroatom; and R is₂、R₃、R₁₀、R₁₂、R₁₄、R₁₈、R₂₀、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₉、R₃₀、R₃₁、R₃₂、R₃₃、R₃₅May independently be H or none; the group directly attached to N or O can also be a metal ion, such as R₁₃、R₁₅、R₁₆、R₂₂、R₂₆、R₃₀、R₃₁、R₃₅Etc. may be lithium/sodium ions, the ring being identical to the ring substituents.

Preferably, E₁Or E₂Selected from the group consisting of alkyl, heteroalkyl, alkenyl, heteroalkenyl, a group containing a cyclic structure, a substituted alkyl group, a substituted alkenyl group or a substituted alkenyl group,

Or ═ N-R₆-, the double bond in the heteroalkenyl group includes a structure containing a carbon-carbon double bond C ═ C and a structure containing a carbon-nitrogen double bond C ═ N, R₄、R₅And R₆Independently of R in the preceding paragraph₂、R₃The species defined in (1) are identical.

Preferably, in the general formula I,the unsaturated heterocycle R' is a three-to twelve-membered ring; a three-membered ring: containing 1 double bond and 1 heteroatom; a four-membered ring: contains 1 double bond and 1 or 2 hetero atoms; five-membered ring: contains 1 or 2 double bonds and 1,2 or 3 hetero atoms; a six-membered ring: contains 1 or 2 double bonds and simultaneously contains 1,2, 3,4, 5 or 6 heteroatoms; a seven-membered ring: contains 1,2 or 3 double bonds and 1,2 or 3 hetero atoms; eight-membered and nine-membered rings: contains 1,2, 3 or 4 double bonds and 1,2 or 3 hetero atoms; ten-, eleven-, and twelve-membered rings: contains 1,2, 3,4 or 5 double bonds and 1,2 or 3 hetero atoms; two-OBF₃M is directly or indirectly attached to any one or two atoms of the heterocyclic ring R' described above.

Preferably, the unsaturated heterocyclic ring R' includes, but is not limited to, the following rings: furan, 3, 4-dihydrofuran, 2, 3-dihydrofuran, thiophene, 2, 3-dihydrothiophene, 3, 4-dihydrothiophene, pyrrole, 3, 4-dihydropyrrole, 2, 3-dihydropyrrole, imidazole, pyrazole, thiazole, oxazole, isoxazole, triazole, dihydrotriazole, thiadiazole, 1, 3-dihydropyridine, 1, 4-dihydropyridine, dihydropyrimidine, tetrahydropyrimidine, dihydropyrazine, tetrahydropyrazine, dihydropyridazine, tetrahydropyridazine, dihydrotriazine, tetrahydrotriazine, pyran, dihydropyran, thiopyran, dihydrothiopyran

In the above-mentioned heterocycle R', the substituent R may be bonded; two-OBF₃M is directly linked or respectively through E₁、E₂Indirectly to any two or one of the atoms of each ring R' as described above.

Preferably, said general formula i includes, but is not limited to, the following compounds:

in the above structure, -OBF₃finger-OBF₃M; e in each ring structure₁And E₂Each independently of E as defined in any of the preceding paragraphs₁And E₂The consistency is achieved; any one H on each unsaturated heterocycle may be independently selected from A₁、A₂、A₃Or A₄Any one substituent of (A), A₁、A₂、A₃And A₄Are each independently selected from any one of the substituents defined in any one of the above paragraphs for substituent R.

Preferably, at said substituent R, A₁、A₂、A₃Or A₄Wherein the halogen atom includes F, Cl, Br, I; r₂、R₃、R₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₅、R₁₆、R₁₇、R₁₈、R₁₉、R₂₀、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₈、R₂₉、R₃₀、R₃₁、R₃₂、R₃₃、R₃₄、R₃₅Independently is C_1-10Alkyl radical, C_1-10Heteroalkyl group, C_1-10Alkenyl or C_1-10Heteroalkenyl, heteroalkyl or heteroalkenyl being alkyl or alkenyl bearing at least one heteroatom; and R is₂、R₃、R₁₀、R₁₂、R₁₄、R₁₈、R₂₀、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₉、R₃₀、R₃₁、R₃₂、R₃₃、R₃₅Can independently be H or nothing, and the radicals directly attached to N or O can also be metal ions, such as R₁₃、R₁₅、R₁₆、R₂₀、R₂₂、R₂₄、R₂₆、R₃₀、R₃₁、R₃₅And the like may be lithium/sodium ions; cyano radicals selected from-CN, -CH₂CN、-SCH₂CH₂CN or-CH₂CH₂CN。

The alkyl group includes methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, -C (CH)₃)₃、-CH(CH₃)₂、-C(CH₃)₂CH₂C(CH₃)₃、-C(CH₃)₂CH₂CH₃(ii) a Heteroalkyl groups include-CH₂NO₂、-CH₂Z₁CH₃、-CH₂CH₂Z₁、-Z₁(CH₂CH₃)₂、-CH₂N(CH₃)₂、-CH₂CH₂-O-NO₂、-CH₂S-S-CH₃、-CH₂Z₁CH(CH₃)₂、-COCH₂CH(CH₃)₂、-OCH₂(CH₂)₆CH₃、-CH₂(CH₃)Z₁CH₃、-CH₂(CH₃)Z₁CH₂CH₃、-CH₂CH₂Z₁CH₃、-CH₂CH(CH₃)Z₁CH₃、-CH(CH₃)CH₂Z₁CH₃、-CH₂CH₂Z₁CH₂CH₃、-CH₂CH₂CH₂Z₁CH₃、-CH₂CH₂CH₂Z₁CH₂CH₃、-CH₂CH(CH₃)CH₂Z₁CH₃、

The alkenyl and heteroalkenyl groups are selected from the group consisting of ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenylAlkenyl, octenyl, nonenyl, decenyl, hexadienyl, -C (CH)₃)＝CH₂、-CH₂CH＝CH(CH₃)₂、-C(CH₃)＝CH₂、-COCH₂CH(CH₃)₂、-CH＝CHCOOCH₂CH₃、-CH₂CH＝CHCH₂CH₃、-C(CH₃)₂CH＝CH₂、-N＝CHCH₃、-OCH₂CH＝CH₂、-CH₂-CH＝CH-Z₁CH₃、

Alkynyl and heteroalkynyl are selected from ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, -C.ident.CCH₂CH₂CH₂Z₁CH₂CH₃、-C≡CCH₂Z₁CH₂CH₃、-C≡C-Si(CH₃)₃。

The cyclic substituents include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and polycyclic; preferably, the cyclic substituent is selected from the group consisting of cyclopropane, oxirane, cyclobutane, cyclobutenyl, cyclobutane, phenyl, pyridine, pyrimidine, cyclopentyl, cyclopentenyl, cyclopentadienyl, pyrrolyl, dihydropyrrolyl, tetrahydropyrrolyl, furanyl, dihydrofuran, tetrahydrofuran, thiophene, dihydrothiophene, tetrahydrothiophene, imidazolyl, thiazolyl, dihydrothiazolyl, isothiazolyl, dihydroisothiazolyl, pyrazolyl, oxazole, dihydrooxazolyl, tetrahydrooxazolyl, isoxazolyl, dihydroisoxazolyl, 1, 3-dioxolane, triazolyl, cyclohexane, cyclohexenyl, cyclohexadiene, piperidine, pyran, dihydropyran, tetrahydropyran, thiopyran, dihydrothiopyran

Tetrahydrothiopyrans, dithianes

1, 2-dithianes

[1,3]Oxazolidines

Dioxane (dioxane)

Morpholine, piperazine, pyrone, pyridazine, pyrazine, triazine, dihydropyridine, tetrahydropyridine, dihydropyrimidine, tetrahydropyrimidine, hexahydropyrimidine, biphenyl, naphthyl, anthryl, phenanthryl, quinonyl, carbazolyl, indolyl, isoindolyl, quinolyl, purinyl, basic, benzoxazole, p-diazepine, pyrenyl, acenaphthenyl, phenanthridinyl, and phenanthridinyl,

Wherein Z is₁Selected from-O-, -S-S-, -CO-,

R₃₆、R₃₇、R₃₈、R₄₃、R₉₀、R₉₁、R₉₂independently selected from H, methyl, ethyl, propyl, isopropyl, butyl, fluoromethyl, fluoroethyl, methoxy, ethenyl, propenyl, or a metal ion; any one ring of the ring substituents is independently connected with the substituted unsaturated heterocyclic ring through any one of the following connecting groups: -CH₂-、-CH₂CH₂-, propyl, butyl, ethylene, propylene, butene, acetylene, propyne, -COO-, -CO-, -SO₂-、-N＝N-、-O-、-OCH₂-、-OCH₂CH₂-、-CH₂OCH₂-、-COCH₂-、-CH₂OCH₂CH₂-、-OCH₂CH₂O-、-COOCH₂CH₂-、-S-、-S-S-、-CH₂OOC-、-CH＝CH-CO-、

Or a single bond, i.e. a direct ring-to-ring connection; r₄₂Independently selected from H, methyl, ethyl or propyl; r₄₇、R₉₃、R₉₇Is independently selected from

Or any one of the linking groups, R₈₃Selected from hydrocarbyl, heterohydrocarbyl, cyclic or metal cations; any atom with H on any ring of the ring substituents can be connected with a first substituent which is consistent with the type defined by the substituent R; preferably, the first substituent is selected from the group consisting of H, halogen atom, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, fluoromethyl, fluoroethyl, methoxy, ethoxy, nitro, alkenyl, alkynyl, ester, sulfonate, sulfoalkane, amide, cyano, aldehyde, -SCH₃、-COOCH₃、COOCH₂CH₃、-OCF₃、＝O、-N(CH₃)₂、-CON(CH₃)₂、-SO₂CH₃or-SO₂CH₂CH₃The ester group includes carbonates, sulfonates, carboxylates, and phosphates as described in any of the above.

Preferably, the substituents R are selected from H, halogen atoms, -R₁₂COOR₁₃、-R₁₂OCOR₁₃、-R₁₂SO₂OR₁₃、R₁₂O-CO-OR₁₃Aldehyde group, -R₁₄OR₁₅、-R₁₆SR₁₇、＝O、＝S、＝CH₂Nitro, -CN, -CH₂CN、-CH₂CH₂CN、

-CH＝N-R₂₄、

-R₁₈SO₂R₁₉Sulfate, sulfonate, sulfonimide, carbonate, carboxylate, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, n-hexyl, isohexyl, sec-hexyl, neohexyl, heptyl, octyl, nonyl, ethenyl, propenyl, butenyl, pentenyl, hexenyl, hexadienyl, ethynyl, propynyl, butynyl, -C (CH), hexadienyl₃)₂CH₂C(CH₃)₃、-C(CH₃)₂CH₂CH₃、-C≡C-Si(CH₃)₃Haloalkyl, haloheteroalkyl,

And cyclic substituents.

Wherein R is₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₅、R₁₆、R₁₇、R₁₈、R₁₉、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₈、R₂₉、R₃₀、R₃₁、R₃₂Independently is methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, trifluoromethyl, alkenyl, and R is₁₀、R₁₂、R₁₄、R₁₆、R₁₈、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₉、R₃₀May independently be H or none; the halogenated alkyl and halogenated heteroalkyl include a group in which any one H of alkyl and alkoxy is substituted by halogen;

the ring substituent is selected from the group consisting of cyclopropane, oxirane, phenyl, pyridine, pyrimidine, cyclopentyl, cyclopentenyl, cyclopentadienyl, pyrrolePhenyl, furyl, thiophene, imidazolyl, thiazolyl, oxazole, dihydrooxazolyl, 1, 3-dioxolane, cyclohexyl, cyclohexenyl, cyclohexadiene, piperidine, pyran, dihydropyran, tetrahydropyran, biphenyl, naphthyl, indolyl, benzoxazole, phenylcarbamoyl, and phenylcarbamoyl,

Wherein any one ring of said cyclic substituents may pass through-CH₂-、-CH₂CH₂-、-CH₂CH₂CH₂-、-COO-、-CO-、-SO₂-、-N＝N-、-O-、-OCH₂-、-OCH₂CH₂-、-CH₂OCH₂-、-COCH₂-、-S-、-S-S-、-CH₂OOC-or a single bond to a substituted unsaturated heterocycle; r₄₃Selected from H, methyl, ethyl or propyl;

the first substituent is preferably H, halogen atom, methyl, ethyl, propyl, isopropyl, butyl, pentyl, fluoromethyl, fluoroethyl, methoxy, ethoxy, nitro, vinyl, ethynyl, cyano, aldehyde group, -SCH₃、-COOCH₃、COOCH₂CH₃、-OCF₃、＝O、-N(CH₃)₂、-CON(CH₃)₂、-SO₂CH₃。

Preferably, E₁Or E₂Is selected from-CH, -CH₂-, ethyl, N-propyl, isopropyl, N-butyl, isobutyl, N-pentyl, isopentyl, sec-pentyl, neopentyl, hexyl, ethenyl, propenyl, butenyl, pentenyl, ethynyl, propynyl, butynyl, cyclohexyl, cyclopentyl, 1, 3-hexadienyl, -C ═ N-, -C (CH)₃)₂-、-CH(CH₃)-、-CH(CF₃)-、-C(CF₃)₂-、-SCH₂CH₂-、-CH₂CH₂SCH₂CH₂-、-CH₂CH₂CH(CH₃)-、-Z₁CH₂CH₂-、-O-CH₂(CH₂)₄CH₂-、-N＝C(CH₃)-、-O-(CH₂)₆-、-CH₂Z₁CH₂-、-CH₂(CH₃)Z₁CH₂-、-CH₂CH₂Z₁CH₂-、

Said keto group comprising-CO-, -CH₂CO-、-CH₂CH₂CO-、-CH₂CH₂CH₂CO-、-CH₂COCH₂-、-CH₂CH₂COCH₂-、-CH＝CH-CO-、-OCH₂CH₂CH₂CO-、＝N-CH₂-CO-、-Z₁CH₂CO-、-Z₁CH₂CH₂CO-、-Z₁CH₂CH₂CH₂CO-、-CH₂(CH₂)₅CO-、-CH₂(CH₂)₆CO-、

The ester group comprises-COOCH₂-、-COOCH₂CH₂-and-CH₂COOCH₂-; wherein Z in this paragraph₁Selected from-O-, -S-S-),

Sulfonyl, sulfonylimino or sulfonyloxy, wherein R₄₁Is H, methyl, ethyl, propyl, isopropyl, butyl, ethoxy or methoxy, and the R is₄₁Any one of hydrogen and H in (1) can be replaced by F or Cl; r₄₄、R₄₅Independently an alkyl group or a ring; r₃₉Selected from H, methyl, ethyl, propyl, butyl, pentyl, cyclopropyl, cyclopentyl, cyclohexyl, nitro, thiazole, -CH (CH)₃)₂、-CH₂CH(CH₃)₂、-CH₂CH₂NO₃、

Wherein R is₈、R₃₇、R₃₈And R₄₀Independently is nothing, halogen atom, methyl, ethyl, propyl, butyl, fluoromethyl, fluoroethyl, methoxy, nitro, aldehyde group, ketone group, ester group, -CH₂-N(CH₃)₂or-CH (CH)₃)-Ph，R₉Is absent or methylene.

Preferably, E₁Or E₂Is selected from-CH, -CH₂-, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, hexyl, ethenyl, propenyl, butenyl, pentenyl, ethynyl, propynyl, butynyl, dienyl, -CO-, -CH₂CO-、-CH₂CH₂CO-、-CH₂CH₂CH₂CO-、-C(CH₃)₂-、-CH(CH₃)-、-CH(CF₃)-、-C(CF₃)₂-、-Z₁CH₂-、-Z₁CH₂CH₂-、-CH₂Z₁CH₂-、CH₂CH₂Z₁CH₂-、-CH₂CH₂Z₁CH₂CH₂-、-COOCH₂-、-COOCH₂CH₂-、-CH₂COOCH₂-、

Wherein Z in this paragraph₁O, S; r₃₉Independently selected from H, methyl, ethyl, propyl, cyclopropyl, cyclopentyl, cyclohexyl, nitro, -CH (CH)₃)₂、-CH₂CH(CH₃)₂、

Wherein R is₉Is absent or methylene; r₈And R₃₇Independently selected from the group consisting of none, methyl, ethyl, propyl, halogen atoms, methoxy, nitroAldehyde groups, fluoromethyl groups, fluoroethyl groups, ketone groups or ester groups.

Preferably, M of said formula I comprises Na⁺、K⁺、Li⁺、Mg²⁺Or Ca²⁺Preferably Na⁺、K⁺Or Li⁺。

Preferably, the general formula i is: a compound wherein H on C in any one of the general formulae i described in any one of the above paragraphs is substituted, wholly or partially, with halogen, preferably F.

It is another aspect of the present invention to provide a method of preparing an electrolyte according to any of the above paragraphs by reacting a binary structure of an unsaturated heterocycle containing two-OH groups, a boron trifluoride compound, and a source of M (e.g., a salt of M, a base of M, or other material capable of providing a metal M to formula i of the present application) to produce a product containing two-OBF₃Unsaturated ring structure of M.

The invention also provides an additive applied to a lithium/sodium battery, which comprises the unsaturated heterocycle-containing boron trifluoride salt described in any one of the above general formulas.

It is still another object of the present invention to provide a lithium/sodium salt for use in a lithium/sodium battery, the lithium/sodium salt comprising a boron trifluoride salt containing an unsaturated heterocycle according to any one of the above general formulae.

It is a further aspect of the present invention to provide an electrolyte comprising a liquid electrolyte, a solid electrolyte, an electrolyte composite membrane or a gel electrolyte, the electrolyte comprising an unsaturated heterocyclic boron trifluoride salt as described in any of the above paragraphs.

The invention also provides a battery, which comprises a liquid battery, a solid-liquid mixed battery or a gel battery; the battery comprises the electrolyte containing the unsaturated heterocycle in any paragraph, a positive electrode, a negative electrode, a diaphragm and a packaging shell.

A final aspect of the present invention is to provide a battery pack including the battery.

The invention has the beneficial effects that:

the electrolyte in the present application creatively combines two-OBF₃M is complexed in one compound, and is preferably-OBF₃M is bonded to the carbon atom C. The unsaturated heterocyclic boron trifluoride organic compound can be used as an additive in liquid or solid electrolyte, can form a stable and compact passivation film on the surface of an electrode of a lithium/sodium battery, prevents direct contact between electrolyte and the electrode, inhibits decomposition of the electrolyte, and can remarkably improve the cycle performance, the discharge specific capacity and the charge-discharge efficiency of the lithium/sodium battery; in addition, the boron organic compound additive is a lithium/sodium ion conductor, and as the additive, a passivation layer formed on the surface of an electrode rarely consumes lithium/sodium ions extracted from the anode during film formation, so that the first coulombic efficiency and the first-cycle discharge specific capacity of the battery can be obviously improved. And when the electrolyte containing the boron organic compound, the existing high-voltage high-specific-volume positive electrode material and the low-voltage high-specific-volume negative electrode material are compounded into a lithium/sodium battery, the electrochemical performance of the battery is improved. In addition, the structure of the application can be mixed with conventional additives for use, namely, the double additives, and the battery using the double additives shows more excellent electrochemical performance.

More importantly, the present application contains 2-OBF₃The boron organic compound of M can be used as a salt in an electrolyte, and more surprisingly, the boron organic compound can also be used as a salt in an all-solid-state battery, which is safer, lithium/sodium ions containing boron in the non-aqueous solvent of the application are easily solvated, higher ionic conductivity is provided for the battery, and the defects of lithium/sodium salts in the traditional electrolyte can be overcome, namely the solid electrolyte containing the boron organic compound salt has the advantages of no corrosion to a current collector and high voltage resistance, and the PEO with a narrow electrochemical window can be matched with a high-voltage (more than 3.9V) positive electrode, so that the electrochemical performance of the lithium/sodium battery is obviously improved. Moreover, the salt in the application can be combined with the traditional lithium/sodium salt as a double salt, and the effect is also good. Furthermore, the use of the structure in the present application, which itself is capable of acting synergistically as an additive property and as a salt property in an electrolyte, gives it an excellent effect superior to that of conventional additives or lithium/sodium salts, e.g., when it is used as a lithium salt,the electrolyte has good ion transmission performance, and a stable passivation layer can be formed on the surface of an electrode in the battery cycling process to prevent further decomposition of PEO or other components, so that the battery has more excellent long-cycle stability.

In addition, the boron organic compound has the advantages of rich raw material sources, wide raw material selectivity, low cost, simple preparation process, mild reaction conditions and excellent industrial application prospect, and only needs to react a compound containing two-OH groups with boron trifluoride organic compounds and an M source (M is a metal cation).

In addition, the metal such as sodium, potassium and the like except for the traditional lithium can be used for forming salt, so that more possibilities are provided for later application, cost control or raw material selection, and the like, and the significance is great.

Drawings

FIGS. 1 to 15 are nuclear magnetic hydrogen spectra of products shown in examples 1 to 15 of the present invention, respectively;

FIG. 16 is a nuclear magnetic carbon spectrum of the product of example 16 of the present invention;

FIGS. 17 to 20 are nuclear magnetic hydrogen spectra of products according to examples 17 to 20 of the present invention, respectively;

FIGS. 21 to 24 are graphs showing the effect of the circulation of the electrolyte additive according to the present application;

FIGS. 25-26 are graphs illustrating the cycling effect of lithium salts as electrolytes in accordance with the present application;

fig. 27 is a graph showing the cycling effect of the lithium salt in the solid electrolyte according to the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to specific embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the present invention, if notWhere the position of the substituent attached to the substituted structure is explicitly indicated, this means that any atom in the substituent may be attached to the atom or structure being substituted, for example: if the substituent is

Then any atom or R on any benzene₄₃Any of the atoms in (a) may be attached to a substituted structure. Furthermore, where two linkages are present in a substituent, the linked structure may be linked to either linkage, e.g.

If R is₉₃is-OCH₂CH₂The linkage on O can be either to the left or to the right phenyl ring, likewise the linkage on methylene is also possible.

In the present invention, if a group is desired to be attached to a two-part structure, it has two linkages or radicals to be attached, and if it is not explicitly indicated which two atoms are attached to the attached part, any one atom containing H may be attached. E if in the claims of this application₁Is n-butyl due to E₁Having 2 linkages to be linked (one with-OBF)₃M connects one to the main structure) and n-butyl has only one connection at the terminus, then the other connection can be at any of the 4 carbon atoms in n-butyl.

In the context of the present invention, a chemical bond is not drawn on an atom, but on a position where it intersects the bond, e.g. on the surface of a metal

Represents any one H on the ring which may be substituted by a substituent A₁And two or more H can be replaced by one H, and the substituents can be the same or different. If a ring atom (which may also be another heteroatom) has multiple hydrogens or may have multiple bonds attached, then the atom may have multiple substituents attached, which may be the same or different, at the same time, and the substituents attached are allIs selected from A₁. For example: if A₁Is methyl, F or ═ O, the abovementioned formulae can then be

And the like. In addition, the ring substituents represented by A or R, etc., are as follows

If with A₁And two H are connected to C, then the two H can be replaced by substituent groups completely or only by 1, and the substituent groups on the two H can be the same or different, for example, two H can be replaced by methyl, or one can be replaced by methyl and one can be replaced by ethyl. In addition, substituents may also be attached to the ring via a double bond, see the foregoing examples in this paragraph.

The "Et" is ethyl. "Ph" is phenyl.

In the structural formulae of the present invention, when a group in the parentheses "()" is contained after a certain atom, it means that the group in the parentheses is connected to the atom before it. Such as-C (CH)₃)₂-is of

-CH(CH₃) -is of

In this application, the xx group may have a bond to the substituted structure, or may have two or three, depending on the actual requirement. If it is a general substituent, it has only one bond, if it is E₁、E₂、E₃Or some R in the second substituent, etc., which has 2 or 3 linkages.

In the title and description of the invention, -OBF₃M in M may be a monovalent, divalent, trivalent or polyvalent metal cation, if it is not a monovalent ion, -OBF₃The number of (c) is increased correspondingly so that it exactly matches the valence of M.

The "boron trifluoride-based compound" refers to boron trifluoride, a compound containing boron trifluoride, a boron trifluoride complex or the like.

The invention provides a binary organic boron trifluoride salt which can be used as an electrolyte additive and an electrolyte lithium/sodium salt at the same time, namely the binary organic boron trifluoride salt contains two-OBF in the organic matter₃M is a group in which M is Li⁺Or Na⁺And the like. The binary boron trifluoride salt can be applied to liquid batteries, and can also be excellently applied to gel batteries and solid batteries. The preparation method of the compound is simple and ingenious, and the yield is high. Namely, the boron trifluoride compound is obtained by reacting a raw material, a boron trifluoride compound and an M source, specifically, -OH in the raw material participates in the reaction, and other structures do not participate in the reaction. The specific preparation method mainly comprises two methods:

adding an M source and a raw material into a solvent under the atmosphere of nitrogen/argon, mixing, reacting at 5-45 ℃ for 1-12 hours, and drying the obtained mixed solution under reduced pressure at 0-50 ℃ and the vacuum degree of about-0.1 MPa to remove the solvent to obtain an intermediate; adding boron trifluoride compounds, stirring and reacting for 6-24 hours at 5-80 ℃, drying the obtained mixed solution under reduced pressure at 30-80 ℃ and under the vacuum degree of about-0.1 MPa to obtain a crude product, and washing, filtering and drying the crude product to obtain a final product, namely the binary organic boron trifluoride salt, wherein the yield is 74-95%.

Secondly, under the atmosphere of nitrogen/argon, adding the raw materials and boron trifluoride compounds into a solvent, uniformly mixing, reacting for 12 hours at the temperature of 5-40 ℃, drying the obtained mixed solution under reduced pressure at the temperature of 0-40 ℃ and the vacuum degree of about-0.1 MPa to remove the solvent, and reacting to obtain an intermediate; adding an M source into a solvent, then adding the solvent containing the M source into an intermediate, stirring and reacting for 6-8 hours at 5-80 ℃ to obtain a crude product, directly washing the crude product or washing the crude product after drying under reduced pressure, and then filtering and drying to obtain a final product, namely the binary organic boron trifluoride salt, wherein the yield is 74-95%.

In the above two specific preparation methods, the boron trifluoride compounds may include boron trifluoride diethyl etherate complex, boron trifluoride tetrahydrofuran complex, boron trifluoride dibutyl etherate complex, boron trifluoride acetic acid complex, boron trifluoride monoethyl amine complex, boron trifluoride phosphoric acid complex, and the like. M sources include lithium/sodium metal tablets, lithium/sodium methoxide, lithium/sodium hydroxide, lithium/sodium ethoxide, butyl lithium/sodium, lithium/sodium acetate, and the like. The solvent is independently alcohol (some liquid alcohol can be used as solvent), ethyl acetate, DMF, acetone, hexane, dichloro, tetrahydrofuran, glycol dimethyl ether, etc. Washing can be carried out with a small polar solvent such as diethyl ether, n-butyl ether, isopropyl ether, hexane, cyclohexane, diphenyl ether, etc.

Example 1: raw materials

The preparation method comprises the following steps: in a nitrogen atmosphere, the starting materials 3-hydroxy-2- (1-hydroxyethyl) -1, 6-dimethylpyridin-4-one (1.83g, 0.01mol) and boron trifluoride tetrahydrofuran complex (2.8g, 0.02mol) were mixed uniformly in 15ml of ethylene glycol dimethyl ether and reacted at room temperature for 12 hours. The obtained mixed solution is decompressed and dried at 40 ℃ and under the vacuum degree of about-0.1 MPa to remove the solvent, and an intermediate is obtained. Dissolving lithium ethoxide (1.04g, 0.02mol) in 10ml of ethanol, slowly adding the mixture into the intermediate, stirring the mixture at room temperature for reaction for 8 hours, drying the obtained mixed solution at 40 ℃ under reduced pressure under the condition of vacuum degree of about-0.1 MPa, washing the obtained solid with n-butyl ether for three times, and filtering and drying the washed solid to obtain a product M1. The yield was 79%, and the nuclear magnetization is shown in FIG. 1.

Example 2: raw materials

The preparation method comprises the following steps: the starting material, 3-hydroxy-2-hydroxymethyl-1-methyl-6- (2,2, 2-trifluoroethyl) -1H-pyridin-4-one (2.37g, 0.01mol) and boron trifluoride diethyl etherate (2.98g,0.021mol) were mixed well in 15ml of THF under an argon atmosphere and reacted at room temperature for 12 hours. The obtained mixed solution is decompressed and dried at 30 ℃ and the vacuum degree of about-0.1 MPa to remove the solvent, and an intermediate is obtained. 14ml of butyllithium in hexane (c: 1.6mol/L) was added to the intermediate, the reaction was stirred at room temperature for 6 hours, the resulting mixture was dried under reduced pressure at 40 ℃ under a vacuum degree of about-0.1 MPa, and the resulting crude product was washed with cyclohexane 3 times, filtered and dried to obtain M2. The yield was 89%, and the nuclear magnetization is shown in FIG. 2.

Example 3: raw materials

The preparation method comprises the following steps: under nitrogen atmosphere, the raw materials 3-hydroxy-2- (1-hydroxyethyl) -1- (2-piperidine) ethyl) pyridin-4 (1H) -one (2.66g, 0.01mol) and lithium methoxide (0.76g,0.02mol) were mixed well with 20ml of methanol and reacted at room temperature for 8 hours. The obtained mixed solution is decompressed and dried at 40 ℃ and under the vacuum degree of about-0.1 MPa to remove the solvent, and an intermediate is obtained. Boron trifluoride tetrahydrofuran complex (3.07g, 0.022mol) is added into the intermediate, stirred and reacted for 7 hours at room temperature, the obtained mixed solution is decompressed and dried at 40 ℃ and the vacuum degree of about-0.1 MPa, the obtained solid is washed three times by isopropyl ether, and the product M3 is obtained after filtration and drying. Yield 82%, nuclear magnetization is shown in fig. 3.

Example 4: raw materials

The preparation method comprises the following steps: the starting material, 3-benzyloxy-2-hydroxymethyl-1-methyl-6- (2,2, 2-trifluoro-1-hydroxy-ethyl) -1H-pyridin-4-one (3.43g, 0.01mol) and boron trifluoride tetrahydrofuran complex (3.07g, 0.022mol) were mixed well in 15ml THF under an argon atmosphere and reacted at room temperature for 12 hours. The obtained mixed solution is decompressed and dried at 30 ℃ and the vacuum degree of about-0.1 MPa to remove the solvent, and an intermediate is obtained. 14ml of a butyl lithium hexane solution (c: 1.6mol/L) was added to the intermediate, the reaction was stirred at room temperature for 6 hours, the resulting mixture was dried under reduced pressure at 35 ℃ under a vacuum degree of about-0.1 MPa, and the resulting crude product was washed with n-hexane 3 times, filtered and dried to obtain M4. The yield was 88%, and the nuclear magnetization is shown in FIG. 4.

Example 5: raw materials

The preparation method comprises the following steps: raw material 2- (3-chloro-phenylazo) -3-hydroxy-6-hydroxymethyl-1 methyl-1H-pyridin-4-one (2.93g, 0.01mol) and boron trifluoride acetic acid complex (3.83g, 0.0204mol) were mixed uniformly in 15ml THF under an argon atmosphere, reacted at 40 ℃ for 12 hours, and the resulting mixed solution was dried under reduced pressure at 40 ℃ and a vacuum degree of about-0.1 MPa to remove the solvent, thereby obtaining an intermediate. Sodium acetate (1.64g, 0.0204mol) was dissolved in 10ml of DMF and added to the intermediate, the reaction was stirred at 45 ℃ for 8 hours, the resulting mixture was dried under reduced pressure at 80 ℃ under a vacuum of about-0.1 MPa, and the resulting solid was washed three times with diphenyl ether, filtered and dried to give product M5. The yield was 79%, and the nuclear magnetization is shown in FIG. 5.

Example 6: raw materials

Preparation: the product M6 was prepared from the starting material by the method of example 3. Yield 88%, nuclear magnetization is shown in fig. 6.

Example 7: raw materials

Preparation: the product M7 was prepared from the starting material by the method of example 1. Yield 76% and nuclear magnetization are shown in figure 7.

Example 8: raw materials

Preparation: the product M8 was prepared from the starting material by the method of example 2. Yield 79% and nuclear magnetization are shown in fig. 8.

Example 9: raw materials

Preparation: the product M9 was prepared from the starting material by the method of example 4. Yield 86%, nuclear magnetization is shown in fig. 9.

Example 10: raw materials

Preparation: the product M10 was prepared from the starting material by the method of example 3. Yield 83%, nuclear magnetization is shown in fig. 10.

Example 11: raw materials

Preparation: the product M11 was prepared from the starting material by the method of example 2. Yield 88%, nuclear magnetization is shown in fig. 11.

Example 12: raw materials

Preparation: the product M12 was prepared from the starting material by the method of example 1. Yield 75%, nuclear magnetization is shown in figure 12.

Example 13: raw materials

Preparation: the product M13 was prepared from the starting material by the method of example 2. Yield 80% and nuclear magnetization is shown in figure 13.

Example 14: raw materials

Preparation: the product M14 was prepared from the starting material by the method of example 1. Yield 76% and nuclear magnetization are shown in figure 14.

Example 15: raw materials

Preparation: the product M15 was prepared from the starting material by the method of example 3. Yield 86%, nuclear magnetization is shown in fig. 15.

Example 16: raw materials

Preparation: the product M16 was prepared from the starting material by the method of example 4. Yield 83%, nuclear magnetization is shown in fig. 16.

Example 17: raw materials

Preparation: the product M17 was prepared from the starting material by the method of example 2. Yield 87%, nuclear magnetization is shown in fig. 17.

Example 18: raw materials

Preparation: the product M18 was prepared from the starting material by the method of example 1. Yield 83%, nuclear magnetization is shown in fig. 18.

Example 19: raw materials

Preparation: the product M19 was prepared from the starting material by the method of example 2. Yield 79% and nuclear magnetization are shown in fig. 19.

Example 20: raw materials

Preparation: the product M20 was prepared from the starting material by the method of example 4. Yield 78%, nuclear magnetization is shown in fig. 20.

Example 21

The unsaturated heterocycle-containing boron trifluoride organic salts protected in the present invention mainly play two roles: 1. the electrolyte is used as an additive in electrolytes (including liquid and solid), mainly plays a role in generating a passivation layer, and greatly improves the first-cycle efficiency, the first-cycle discharge specific capacity, the long-cycle stability and the rate capability of the battery. 2. The electrolyte (including liquid and solid) is used as salt capable of providing ion transmission, and has high conductivity and good electrochemical performance. The performance of the present application is described below by way of tests.

Firstly, as an electrolyte additive

(1) Positive pole piece

Adding the active substance of the main material of the positive electrode, the electronic conductive additive and the binder into a solvent according to the mass ratio of 95:2:3, wherein the solvent accounts for 65% of the total slurry, and uniformly mixing and stirring to obtain positive electrode slurry with certain fluidity; and coating the anode slurry on an aluminum foil, drying and compacting to obtain the usable anode piece. Lithium cobaltate (LiCoO) is selected as the active material₂LCO for short), lithium nickel cobalt manganese oxide (NCM811 for selection), lithium nickel cobalt aluminate (LiNi)_0.8Co_0.15Al_0.05O₂Abbreviated NCA) and lithium nickel manganese oxide (LiNi)_0.5Mn_1.5O₄Abbreviated LNMO), Na_0.9[Cu_0.22Fe_0.3Mn_0.48]O₂(NCFMO for short), Carbon Nanotubes (CNT) and SuperP are selected for the electron conductive additive, polyvinylidene fluoride (PVDF) is used as the binder, and N-methylpyrrolidone (NMP) is used as the solvent.

(2) Negative pole piece

Adding a main negative material active substance (except metal Li), an electronic conductive additive and a binder into solvent deionized water according to a ratio of 95:2.5:2.5, wherein the solvent accounts for 42% of the total slurry, and uniformly mixing and stirring to obtain negative slurry with certain fluidity; and coating the negative electrode slurry on copper foil, drying and compacting to obtain the usable negative electrode piece. Graphite (C), silicon carbon (SiOC450), metallic lithium (Li) and Soft Carbon (SC) are selected as the active materials, CNT and SuperP are used as the conductive agents, and carboxymethyl cellulose (CMC) and Styrene Butadiene Rubber (SBR) are used as the binders.

The anode and cathode systems selected by the invention are shown in table 1:

TABLE 1 Positive and negative electrode system

(3) Preparing an electrolyte

M1-M20, an organic solvent, a conventional lithium/sodium salt and a conventional additive are uniformly mixed to obtain a series of electrolytes E1-E20, wherein the used solvents are Ethyl Methyl Carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), Ethylene Carbonate (EC) and Propylene Carbonate (PC). Conventional additives are fluoroethylene carbonate (FEC), Vinylene Carbonate (VC), trimethyl phosphate (TMP), ethoxypentafluorocyclotriphosphazene (PFPN), vinyl sulfate (DTD); conventional lithium salts are lithium bis (oxalato) borate (LiBOB), lithium difluoro (oxalato) borate (LiODFB), lithium bis (fluorosulfonyl) imide (LiFSI), lithium hexafluorophosphate (LiPF)₆) Lithium bis (trifluoromethyl) sulfonimide (LiTFSI), sodium hexafluorophosphate (NaPF)₆). The specific components and ratios are shown in table 2.

TABLE 2 electrolytes E1 to E20 formulated with M1 to M20 as additives

Note: 1M means 1 mol/L.

Comparison sample: and replacing M1-M20 with blanks according to the proportion of E1-E20 (namely, not adding M1-M20), thus obtaining corresponding conventional electrolyte comparison samples L1-L20.

(4) Button cell assembly

Electrolyte series E1-E20 containing the structure of the embodiment as an additive and conventional electrolyte L1-L20 are assembled into the button cell in a comparison mode, and the button cell is specifically as follows: negative electrode shell, negative electrode pole piece, PE/Al₂O₃A button cell is assembled by a diaphragm, an electrolyte, a positive pole piece, a stainless steel sheet, a spring piece and a positive pole shell, and a long circulation test is carried out at room temperature, wherein the circulation modes are 0.1C/0.1C1 week, 0.2C/0.2C5 week and 1C/1C44 week (C represents multiplying power), the positive pole piece is a circular sheet with the diameter of 12mm, the negative pole piece is a circular sheet with the diameter of 14mm, the diaphragm is a circular sheet with the diameter of 16.2mm, and is a commercial Al circular sheet₂O₃a/PE porous separator.

The battery systems prepared from E1 to E20 were batteries 1 to 20, respectively, and the battery systems prepared from L1 to L20 were comparative batteries 1 to 20, respectively. The specific configuration and voltage range of the cell are shown in table 3. The results of the first cycle specific discharge capacity, the first cycle efficiency, and the capacity retention rate at 50 cycles of the batteries 1 to 20 and the comparative batteries 1 to 20 at room temperature are shown in table 4.

TABLE 3 arrangement and test mode for batteries 1-20 of examples and comparative batteries 1-20

TABLE 4 comparison of test results for batteries 1-20 of examples and comparative batteries 1-20

From the test results of the battery and the comparative battery, in the button battery, when the positive and negative electrode systems are the same, the first cycle efficiency, the discharge specific capacity and the capacity retention rate of the lithium/sodium battery using the structure M1-M20 as the electrolyte additive are much better than those of the lithium/sodium battery without the electrolyte additive, and the performance of the lithium/sodium battery is superior to that of the conventional additive at present. In addition, the batteries using the additives containing lithium borate salts exhibit more excellent electrochemical performance in the presence of conventional additives.

II, as lithium/sodium salt in electrolyte

(1) Preparing an electrolyte

M1-M20, an organic solvent and a conventional additive are uniformly mixed to obtain a series of electrolytes R1-R20, and a series of conventional electrolytes Q1-Q20 are uniformly mixed to obtain a series of conventional electrolytes Q1-Q20, wherein the used solvent and the conventional additive comprise the solvent and the conventional additive described in the 'first' embodiment. The specific components and ratios of the electrolyte are shown in table 5.

TABLE 5 electrolytes prepared from lithium/sodium salts of electrolytes

(2) Battery assembly

The obtained series of electrolytes R (shown in table 5) and the conventional electrolyte Q (shown in table 5) are assembled into a button cell, and the size of the positive electrode, the negative electrode, the size of the diaphragm, the assembly method and the circulation mode of the cell are respectively 1-20 cells and corresponding comparative cells as the button cell shown in the 'one' of the embodiment. Specific configurations, cycling modes and voltage ranges of the batteries are shown in table 6, and specific first-cycle discharge capacity, first-cycle efficiency and 50-cycle capacity retention rate results of the batteries and comparative batteries at room temperature are shown in table 7.

Table 6 configuration and test mode for example and comparative batteries

Table 7 comparison of test results for example and comparative batteries shown in table 6

In conclusion, in the non-aqueous solvent, lithium/sodium ions are easily solvated, so that high ionic conductivity is provided for the battery, and in a liquid lithium/sodium battery system with LCO, NCM811, NCA and NCFMO as the positive electrode and SiOC450, Li, C and SC as the negative electrode, the lithium/sodium battery system has very excellent electrochemical performance, high first-efficiency and first-week discharge capacity and capacity retention rate and performance basically no inferior to that of a battery corresponding to the traditional lithium salt/sodium.

Thirdly, as lithium salt in solid electrolyte

(1) Preparation of Polymer electrolyte Membrane

M11, M12, M14, M16, M17, M18, M19, a polymer, an inorganic filler and a solvent are uniformly mixed to obtain series of polymer electrolyte slurry, the slurry is coated on a glass plate in a blade mode, and after drying and removing the solvent, polymer electrolyte membranes G11, G12, G14, G16, G17, G18 and G19 and polymer comparative electrolytes G '1-G' 2 are obtained, wherein specific components, proportions and the like are shown in Table 8. The polymer is polyethylene oxide (PEO)

TABLE 8 concrete composition and compounding ratio of polymer electrolyte

Polymer electrolyte membrane

Polymer and method of making same

Lithium/sodium salt

Inorganic filler

The former mass ratio

Solvent(s)

G11

PEO

100 ten thousand

M11

/

4.2：1

DMF

G12

PEO

100 ten thousand

M12

200nm LLZO

4.2：1：0.8

DMF

G14

PEO

100 ten thousand

M14

/

4.2：1

DMF

G16

PEO

100 ten thousand

M16

/

4.2：1

DMF

G17

PEO

100 ten thousand

M17

/

4.2：1

DMF

G18

PEO

100 ten thousand

M18

200nm LLZO

4.2：1：0.8

DMF

G19

PEO

100 ten thousand

M19

/

4.2：1

DMF

G’1

PEO 100 ten thousand

LiTFSI

200nm LLZO

4.2：1：0.8

DMF

G’2

PEO 100 ten thousand

LiTFSI

/

4.2：1

DMF

(2) Preparation of positive pole piece

In an environment with the water content lower than 100ppm, adding the active substance of the positive electrode main material, the polymer and the lithium salt, the electronic conductive additive and the binder into NMP according to the mass ratio of 80:10:5:5, mixing and stirring uniformly, coating the positive electrode slurry on aluminum foil, and drying to obtain the all-solid-state positive electrode piece. Lithium cobaltate (LiCoO) is selected as the active material₂LCO for short), nickel cobalt lithium manganate (NCM811 for selection), Super P for electronic conductive additive, polyvinylidene fluoride (PVDF) for binder

(3) Battery assembly and testing

The polymer electrolyte membrane and the positive and negative pole pieces are assembled into the all-solid button cell, which comprises the following specific steps: and assembling the negative electrode shell, the Li sheet, the polymer electrolyte membrane, the positive electrode sheet, the stainless steel sheet, the spring sheet and the positive electrode shell into a button cell to obtain the lithium secondary cell, and carrying out 50 ℃ long cycle test on the cell in a cycle mode of 0.1C/0.1C 2 cycle and 0.5/0.5C 48 cycle. The positive electrode plate is a circular plate with the diameter of 12mm, the Li plate is a circular plate with the diameter of 14mm, the polymer electrolyte membrane is a circular plate with the diameter of 16.2mm, the specific assembly system and the test method of the battery are shown in Table 9, and the test results are shown in Table 10.

Table 9 arrangement and test mode of example and comparative example batteries

Table 10 comparison of test results of example cells and comparative cells in table 9

From the data in tables 9 and 10, it can be seen that the batteries prepared by M11, M12, M14, M16, M17, M18 and M19 of the present application have excellent long-cycle stability and the performance is superior to the cycle performance of the battery corresponding to LiTFSI. This is because PEO is easily catalytically decomposed by the positive electrode with the electrochemical window of 3.9V, the battery charged to 4.2V; in addition, LiTFSI corrodes the current collector severely, so the comparative example cell exhibited poor cycling performance. The lithium salt synthesized by the method has good ion transmission performance, and a stable passivation layer can be formed on the surface of an electrode in the battery circulation process to prevent PEO from being further decomposed, so that the battery shows more excellent long-cycle stability.

In addition, the figure part selects some effect graphs as additives and lithium salts as displays. FIGS. 21-24 show a battery 2/6/12/17 made with the electrolyte additive of EXAMPLE 2/6/12/17 and a corresponding battery not containing an embodiment of the inventionThe effect of comparative battery 2/6/12/17 is compared to the figure. FIGS. 25-26 are graphs comparing the effect of the battery 11/14 made of the lithium salt electrolyte of example 11/14 with that of a comparative battery 11/14 without the embodiment of the present invention. Fig. 27 is a graph comparing the effects of the battery 17 of example 17 as a solid electrolyte lithium salt and the comparative battery 2 with LiTFSI as a lithium salt. The figures also show that the structure of the application has excellent effect. In addition, in the circulation diagram, there are small squares on the upper surface

The lines of (A) represent the cells of the examples, with small circles

The lines representing the cells of the comparative examples represent the cells of the comparative examples, and it can be seen that the lines representing the cells of the examples are all above the lines representing the cells of the comparative examples, and the cells of the examples have better effects.

In summary, the first cycle efficiency, specific discharge capacity, capacity retention rate, and other properties have a direct and significant impact on the overall performance of the battery, which directly determines whether the battery can be used. Therefore, it is the goal or direction of many researchers in this field to improve these properties, but in this field, the improvement of these properties is very difficult, and generally about 3-5% improvement is a great progress. In the early test data, the data are surprisingly found to be greatly improved compared with the conventional data, particularly when the additive is used as an electrolyte additive, the performance is improved by about 5-30%, and the additive and the conventional additive in the application also show better effect when being used together. More surprisingly, the component can also be used as salt in electrolyte, the effect is very good, and tests show that the performance of the component is basically no inferior to that of a battery corresponding to the traditional lithium salt, and even superior to that of the existing mature component. Further, the structure in the present application can be applied to a solid electrolyte and exhibits excellent effects. More importantly, the structure type of the application is greatly different from the conventional structure, a new direction and thought are provided for the research and development in the field, a large space is brought for further research, and one structure in the application has multiple purposes and great significance.

Example 22

For further study and understanding of the structural properties in the present application, the applicant evaluated the effect of the above 4 structures as electrolyte additives on the long cycle performance of the battery at room temperature. The structure of the present application was selected from the structure in example 11 (i.e., M11), and the following 4 comparative example structures were structure W1, structure W2, structure W3, and structure W4, respectively.

The influence of W1-W4 and M11 on the long-cycle performance of the battery at room temperature is evaluated by respectively using the electrolyte additives.

(1) Electrolyte preparation

Tables 11W 1 to W4 and M11 electrolytes S1 to S5 each prepared as an electrolyte

In the above table, S0 is a control group.

(2) Button cell assembly

The obtained electrolytes S0-S5 were assembled into button cells, and the sizes of the positive and negative electrodes, the separator, the assembly method, and the battery cycle were the same as those of the button cells shown in "I" of example 21, namely, batteries Y0-Y5, respectively. The specific configuration, cycling profile and voltage range of the cell are shown in table 12 and the test results are shown in table 13.

TABLE 12 cell Assembly and test mode

TABLE 13 test results for batteries

The test results of the batteries Y0-Y5 show that the batteries W1-W4 and M11 which are used as electrolyte additives can improve the first efficiency, the specific discharge capacity of 1-50 cycles and the capacity retention rate of the batteries. However, compared with W1-W4, M11 has more obvious improvement on the first effect and first-cycle specific discharge capacity of the battery, probably because W1-W2 contain 1-OBF₃-N-BF of M, W3₃BF-O in W4, not containing lithium₃The complex is not bonded, is chemically unstable and does not contain lithium, and contains two-OBF₃M11 of M contains a lithium source, and lithium ions extracted from the positive electrode are less consumed in the process of forming a good passivation layer, so that the first effect, the first-cycle discharge specific capacity and the capacity retention rate of the battery are achieved. I.e., the organic boron trifluoride salt in this application, acts as both an additive and a lithium/sodium salt in the electrolyte, such as M11, which itself acts synergistically in the electrolyte and is therefore more effective than the other components. The applicant is still in further research with a clearer and more clear mechanism. However, in any case, it is certain that the OBF₃The presence and amount of M has a substantial effect on battery performance.

In the present invention, the structures in examples 1 to 20 were selected as representative to explain the production method and effects of the present application. Other structures not shown can be prepared by the method described in any of examples 1 to 5. The preparation method is that the raw material, boron trifluoride compounds and M source react to obtain the product boron trifluoride organic salt, namely-OH in the raw material is changed into-OBF₃M, M may be Li⁺、Na⁺Etc., and the other structures are not changed. In addition, many research teams of the applicant have already made serial effect tests, which are similar to the effect in the above embodiments, such as: from raw materials

Etc. in the present application, all of which are effectiveIt is good, but only partial structural data is recorded due to space relation.

In the present invention, it is also noted that (i) -OBF₃-BF of M₃It must be bonded to the oxygen atom O, which is in turn bonded by a single bond to the carbon atom C, so that O cannot be a ring-located oxygen. If O is bonded to N, S or another atom, or if O is located on a ring (or if O is bonded to another two groups), the structure is greatly different from the present application, and therefore, it cannot be predicted whether such a structure can be applied to the electrolyte of the present application, what effects and application scenarios are expected, and therefore, the inventors of the present invention will conduct independent studies on these structures, and will not conduct much discussion here; ② the structure does not contain sulfydryl. ③ the electrolyte of the unsaturated heterocyclic boron trifluoride is preferably non-polymeric organic matter, and the polymeric state has unique characteristics and characteristics, so the applicant may study the polymeric state specially in the future, and the non-polymeric state is the present application.

In the present application, the above three cases are all required to be satisfied, and if not, the properties of the present application are greatly different, so that the application scene or effect after change is not well predicted, and may be greatly changed, and if valuable, the present inventors will perform special research separately later.

In the invention, the applicant performs a great amount of tests on the series of structures, after the first structure effect is obtained, the span of the subsequent test exploration and data supplement is about two years, and sometimes, for better comparison with the existing system, the same structure and system exist, and more than one test is performed, so that certain errors may exist in different tests.

Finally, it should be noted that: the above-mentioned embodiments are only used for illustrating the technical solution of the present invention, and not for limiting the same; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An electrolyte of boron trifluoride salts containing an unsaturated heterocycle, characterized in that: the electrolyte comprises unsaturated heterocyclic boron trifluoride salt represented by the following general formula I:

in the general formula I, R' represents an unsaturated heterocyclic ring, and the unsaturated heterocyclic ring contains at least one heteroatom and at least one unsaturated bond; the heteroatom is selected from S, N, O, P, Se, Ca, Al, B or Si; m is a metal cation; e₁、E₂Independently is nothing, a group, a chain structure or a structure containing a ring;

r is a substituent, any one H on the substituent can be substituted by the substituent, and the substituent can be substituted by one H and can also be substituted by two or more H, if two or more H are substituted, the substituents can be the same or different.

2. The electrolyte of claim 1, wherein: in the general formula I, the unsaturated heterocycle is a three-to twenty-membered ring; the unsaturated bond is a double bond;

two of the general formula I-OBF₃M may be ortho, meta, separated by 2 atoms, or separated by more than two atoms;

preferably, in the formula I, with-OBF₃The atom to which M is attached is a carbon atom C; the heteroatom is selected from S, N, O, P or Si.

3. The electrolyte of claim 2, wherein: h on any one C in the general formula I can be independently substituted by halogen;

preferably, in two of the formula I-OBF₃In M, at least one is bonded to a carbon atom other than the non-carbonyl carbon, theCarbonyl carbons include-C ═ O or-C ═ S.

4. The electrolyte of claim 3, wherein: the substituent R is selected from H, halogen atom and carbonyl

A group, an ester group, an aldehyde group, an ether oxygen group, an ether sulfur group, ═ O, ═ S, a,

Nitro, cyano, amino, amide, sulfonamide, sulfoalkane, sulfonic acid group, hydrazino, diazo, alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, alkenylalkynyl, heteroalkynyl, cyclic substituent, salt substituent, and a group in which any one hydrogen H in these groups is substituted with a halogen atom;

wherein the ester group includes carboxylate, carbonate, sulfonate and phosphate, R₂、R₃Independently is H, alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl, alkenynyl, heteroalkynynyl, or ring;

preferably, any one of the structures of heteroalkyl, heteroalkenyl, heteroalkynyl, and heteroalkynyl contains at least one of the non-carbon atoms selected from halogen, S, N, O, P, Se, Ca, Al, B, or Si; the ring substituent comprises a ternary-eight-membered ring and a polycyclic ring formed by at least two monocyclic rings; such salt substituents include, but are not limited to, sulfate, sulfonate, sulfonimide salts, carbonate, carboxylate, thioether, oxoether, ammonium, hydrochloride, nitrate, azide, silicate, phosphate;

the carbonyl group is-R₁₀COR₁₁The ester group is-R₁₂COOR₁₃、-R₁₂OCOR₁₇、-R₁₂SO₂OR₁₃、R₁₂O-CO-OR₁₃Or

or-CH ═ N-R₂₄Amide is

Sulfonamide group of

Wherein R is₂、R₃、R₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₅、R₁₆、R₁₇、R₁₈、R₁₉、R₂₀、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₈、R₂₉、R₃₀、R₃₁、R₃₂、R₃₃、R₃₄、R₃₅Independently is alkyl, heteroalkyl, alkenyl, heteroalkenyl, alkynyl, heteroalkynyl or cyclic, heteroalkane/alkene/alkynyl being an alkane/alkene/alkynyl bearing at least one of the non-carbon atoms; and R is₂、R₃、R₁₀、R₁₂、R₁₄、R₁₈、R₂₀、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₉、R₃₀、R₃₁、R₃₂、R₃₃、R₃₅May independently be H or none; the group directly attached to N or O can also be a metal ion.

5. The electrolyte of claim 4, wherein: e₁Or E₂Selected from the group consisting of alkyl, heteroalkyl, alkenyl, heteroalkenyl, a group containing a cyclic structure, a substituted alkyl group, a substituted alkenyl group or a substituted alkenyl group,

Or ═ N-R₆-，The double bond in the heteroalkenyl group includes a structure containing a carbon-carbon double bond C ═ C and a structure containing a carbon-nitrogen double bond C ═ N, R₄、R₅And R₆Independently of R in claim 4₂、R₃The species defined in (1) are identical.

6. The electrolyte of claim 5, wherein: in the general formula I, the unsaturated heterocyclic ring R' is a three-to twelve-membered ring; a three-membered ring: containing 1 double bond and 1 heteroatom; a four-membered ring: contains 1 double bond and 1 or 2 hetero atoms; five-membered ring: contains 1 or 2 double bonds and 1,2 or 3 hetero atoms; a six-membered ring: contains 1 or 2 double bonds and simultaneously contains 1,2, 3,4, 5 or 6 heteroatoms; a seven-membered ring: contains 1,2 or 3 double bonds and 1,2 or 3 hetero atoms; eight-membered and nine-membered rings: contains 1,2, 3 or 4 double bonds and 1,2 or 3 hetero atoms; ten-, eleven-, and twelve-membered rings: contains 1,2, 3,4 or 5 double bonds and 1,2 or 3 hetero atoms; two-OBF₃M is directly or indirectly attached to any one or two atoms of the heterocyclic ring R' described above.

Preferably, the unsaturated heterocyclic ring R' includes, but is not limited to, the following rings: furan, 3, 4-dihydrofuran, 2, 3-dihydrofuran, thiophene, 2, 3-dihydrothiophene, 3, 4-dihydrothiophene, pyrrole, 3, 4-dihydropyrrole, 2, 3-dihydropyrrole, imidazole, pyrazole, thiazole, oxazole, isoxazole, triazole, dihydrotriazole, thiadiazole, 1, 3-dihydropyridine, 1, 4-dihydropyridine, dihydropyrimidine, tetrahydropyrimidine, dihydropyrazine, tetrahydropyrazine, dihydropyridazine, tetrahydropyridazine, dihydrotriazine, tetrahydrotriazine, pyran, dihydropyran, thiopyran, dihydrothiopyran, dihydrothiophene, and derivatives thereof,

In the above-mentioned heterocycle R', the substituent R may be bonded; two-OBF₃M is directly connected orRespectively through E₁、E₂Indirectly to any two or one of the atoms of each ring R' as described above.

7. The electrolyte of claim 6, wherein: the general formula I includes, but is not limited to, the following compounds:

in the above structure, -OBF₃finger-OBF₃M; e in each ring structure₁And E₂Are each independently of E as defined in any one of claims 1 to 6₁And E₂The consistency is achieved;

any one H on each unsaturated heterocycle may be independently selected from A₁、A₂、A₃Or A₄Any one substituent of (A), A₁、A₂、A₃And A₄Are each independently selected from any one of the substituents defined in substituent R in any one of claims 1 to 6.

8. The electrolyte of any one of claims 4-7, wherein: at said substituent R, A₁、A₂、A₃Or A₄Wherein the halogen atom includes F, Cl, Br, I;

R₂、R₃、R₁₀、R₁₁、R₁₂、R₁₃、R₁₄、R₁₅、R₁₆、R₁₇、R₁₈、R₁₉、R₂₀、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₈、R₂₉、R₃₀、R₃₁、R₃₂、R₃₃、R₃₄、R₃₅independently is C_1-10Alkyl radical, C_1-10Heteroalkyl group, C_1-10Alkenyl or C_1-10Heteroalkenyl, heteroalkyl or heteroalkenyl being alkyl or alkenyl bearing at least one heteroatom; and R is₂、R₃、R₁₀、R₁₂、R₁₄、R₁₈、R₂₀、R₂₁、R₂₂、R₂₃、R₂₄、R₂₅、R₂₆、R₂₇、R₂₉、R₃₀、R₃₁、R₃₂、R₃₃、R₃₅Can independently be H or nothing, and the group directly attached to N or O can also be a metal ion;

cyano radicals selected from-CN, -CH₂CN、-SCH₂CH₂CN or-CH₂CH₂CN；

The alkyl group includes methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl;

heteroalkyl groups include-CH₂NO₂、-CH₂Z₁CH₃、-CH₂CH₂Z₁、-Z₁(CH₂CH₃)₂、-CH₂N(CH₃)₂、-CH₂CH₂-O-NO₂、-CH₂S-S-CH₃、-CH₂Z₁CH(CH₃)₂、-COCH₂CH(CH₃)₂、-OCH₂(CH₂)₆CH₃、-CH₂(CH₃)Z₁CH₃、-CH₂(CH₃)Z₁CH₂CH₃、-CH₂CH₂Z₁CH₃、-CH₂CH(CH₃)Z₁CH₃、-CH(CH₃)CH₂Z₁CH₃、-CH₂CH₂Z₁CH₂CH₃、-CH₂CH₂CH₂Z₁CH₃、-CH₂CH₂CH₂Z₁CH₂CH₃、-CH₂CH(CH₃)CH₂Z₁CH₃、

The alkenyl and heteroalkenyl groups are selected from the group consisting of ethenyl, propenyl, butenyl, pentenyl, hexenyl, heptenyl, octenyl, nonenyl, decenyl, hexadienyl, -C (CH)₃)＝CH₂、-CH₂CH＝CH(CH₃)₂、-C(CH₃)＝CH₂、-COCH₂CH(CH₃)₂、-CH＝CHCOOCH₂CH₃、-CH₂CH＝CHCH₂CH₃、-C(CH₃)₂CH＝CH₂、-N＝CHCH₃、-OCH₂CH＝CH₂、-CH₂-CH＝CH-Z₁CH₃、

Alkynyl and heteroalkynyl are selected from ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl, -C.ident.CCH₂CH₂CH₂Z₁CH₂CH₃、-C≡CCH₂Z₁CH₂CH₃、-C≡C-Si(CH₃)₃；

The cyclic substituents include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and polycyclic; preferably, the cyclic substituents are selected from the group consisting of cyclopropane, oxirane, cyclobutane, cyclobutenyl, cyclobutane, phenyl, pyridine, pyrimidine, cyclopentyl, cyclopentenyl, cyclopentadienyl, pyrrolyl, dihydropyrrolyl, tetrahydropyrrolyl, furanyl, dihydrofuran, tetrahydrofuran, thiophene, dihydrothiophene, tetrahydrothiophene, imidazole, thiazole, dihydrothiazolyl, isothiazolyl, dihydroisothiazolyl, pyrazole, oxazole, dihydrooxazolyl, tetrahydrooxazolePhenyl, isoxazole, dihydroisoxazolyl, 1, 3-dioxolane, triazolyl, cyclohexyl, cyclohexenyl, cyclohexadiene, piperidine, pyran, dihydropyran, tetrahydropyran, thiopyran, dihydrothiopyran, tetrahydrothiopyran, dithiane, 1, 2-dithiane, [1, 3-dithiane]Oxazolidines, dioxanes, morpholines, piperazines, pyrones, pyridazines, pyrazines, triazines, dihydropyridines, tetrahydropyridines, dihydropyrimidines, tetrahydropyrimidines, hexahydropyrimidines, biphenyls, naphthyls, anthracenyls, phenanthrenyls, quinonyls, carbazolyl, indolyl, isoindolyl, quinolyl, purinyl, alkanyl, benzoxazoles, p-diazabenzenes, pyrenyl, acenaphthylenyl, phenanthridinyl, pyrazolidinyl, and pyrazolidinyl,

Wherein, Z in the present claims₁Selected from-O-, -S-S-, -CO-,

R₃₆、R₃₇、R₃₈、R₄₃、R₉₀、R₉₁、R₉₂independently selected from H, methyl, ethyl, propyl, isopropyl, butyl, fluoromethyl, fluoroethyl, methoxy, ethenyl, propenyl, or a metal ion;

any one ring of the ring substituents is independently connected with the substituted unsaturated heterocyclic ring through any one of the following connecting groups: -CH₂-、-CH₂CH₂-, propyl, butyl, ethylene, propylene, butene, acetylene, propyne, -COO-, -CO-, -SO₂-、-N＝N-、-O-、-OCH₂-、-OCH₂CH₂-、-CH₂OCH₂-、-COCH₂-、-CH₂OCH₂CH₂-、-OCH₂CH₂O-、-COOCH₂CH₂-、-S-、-S-S-、-CH₂OOC-、-CH＝CH-CO-、

Or a single bond; r₄₂Independently selected from H, methyl, ethyl or propyl; r₄₇、R₉₃、R₉₇Is independently selected from

Or any one of the linking groups, R₈₃Selected from hydrocarbyl, heterohydrocarbyl, cyclic or metal cations;

any atom with H on any ring of the ring substituents can be connected with a first substituent which is consistent with the type defined by the substituent R; preferably, the first substituent is selected from the group consisting of H, halogen atom, methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, n-pentyl, isopentyl, sec-pentyl, neopentyl, fluoromethyl, fluoroethyl, methoxy, ethoxy, nitro, alkenyl, alkynyl, ester, sulfonate, sulfoalkane, amide, cyano, aldehyde, -SCH₃、-COOCH₃、COOCH₂CH₃、-OCF₃、＝O、-N(CH₃)₂、-CON(CH₃)₂、-SO₂CH₃or-SO₂CH₂CH₃And the ester group includes the carbonates, sulfonates, carboxylates and phosphates.

9. The electrolyte of any one of claims 1-8, wherein: e₁Or E₂Is selected from-CH, -CH₂-, ethyl, N-propyl, isopropyl, N-butyl, isobutyl, N-pentyl, isopentyl, sec-pentyl, neopentyl, hexyl, ethenyl, propenyl, butenyl, pentenyl, ethynyl, propynyl, butynyl, cyclohexyl, cyclopentyl, 1, 3-hexadienyl, -C ═ N-, -C (CH)₃)₂-、-CH(CH₃)-、-CH(CF₃)-、-C(CF₃)₂-、-SCH₂CH₂-、-CH₂CH₂SCH₂CH₂-、-CH₂CH₂CH(CH₃)-、-Z₁CH₂CH₂-、-O-CH₂(CH₂)₄CH₂-、-N＝C(CH₃)-、-O-(CH₂)₆-、-CH₂Z₁CH₂-、-CH₂(CH₃)Z₁CH₂-、-CH₂CH₂Z₁CH₂-、

-O-CH2-CH2-O-CH2-CH2-、

The ester group comprises-COOCH₂-、-COOCH₂CH₂-and-CH₂COOCH₂-；

Wherein, Z in the claim₁Selected from-O-, -S-S-),

Sulfonyl, sulfonylimino or sulfonyloxy, wherein R₄₁Is H, methyl, ethyl, propyl, isopropyl, butyl, ethoxy or methoxy, and the R is₄₁Any one of hydrogen and H in (1) can be replaced by F or Cl; r₄₄、R₄₅Independently an alkyl group or a ring;

R₃₉selected from H, methyl, ethyl, propyl, butyl, pentyl, cyclopropyl, cyclopentyl, cyclohexyl, nitro, thiazole, -CH (CH)₃)₂、-CH₂CH(CH₃)₂、-CH₂CH₂NO₃、

Wherein R is₉Is absent or methylene; r₈And R₃₇Independently selected from the group consisting of none, methyl, ethyl, propyl, halogen atoms, methoxy, nitro, aldehyde, fluoromethyl, fluoroethyl, ketone, or ester groups.

10. The electrolyte of claim 1, wherein: m of the formula I comprises Na⁺、K⁺、Li⁺、Mg²⁺Or Ca²⁺Preferably Na⁺、K⁺Or Li⁺；

Preferably, the general formula i is: a compound of any one of claims 1 to 9 wherein all H on C are substituted, wholly or partially, with halogen, preferably F.

11. A method for producing the electrolyte according to any one of claims 1 to 10, characterized in that: the method comprises the step of reacting an unsaturated heterocyclic binary structure containing two-OH groups, a boron trifluoride compound and an M source to obtain a product, namely the product contains two-OBF₃And the unsaturated heterocyclic structure of M.

12. Use of an unsaturated heterocyclic boron trifluoride salt electrolyte according to any of claims 1 to 10 in a secondary lithium battery, characterized in that: the application is as follows: the electrolyte can be used both as a lithium/sodium salt and as an additive;

preferably, the application comprises application in a liquid electrolyte, a solid electrolyte, an electrolyte composite membrane or a gel electrolyte, each of which independently comprises an unsaturated heterocyclic boron trifluoride salt electrolyte according to any one of claims 1 to 10;

preferably, the use further comprises use as a battery or battery, said battery comprising an unsaturated heterocyclic boron trifluoride salt electrolyte according to any one of claims 1 to 10 and a positive electrode, a negative electrode, a separator and a package housing; the battery pack includes the battery.