A solid-state electrolyte precursor, a solid-state electrolyte and a preparation method thereof

Abstract

The present disclosure relates to the field of solid-state electrolyte, in particular to a solid-state electrolyte precursor, a solid-state electrolyte and a preparation method thereof. The solid-state electrolyte precursor comprises the following: a mixed solvent, a lithium salt, a mesoporous material, a first compound and a second compound; wherein the lithium salt is selected from lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate and the like; the mixed solvent comprises the following components: a component a: an alcohol or ether solvent; a component b: one or more of the following compounds: thionyl chloride, trimethylsulfonium bromide, sulfuryl bromide and the like. The present disclosure prepares a solid-state electrolyte precursor which is stable and storage-resistant itself, and can form a framework type three-dimensional structure material after the addition of a catalyst without the need for additional initiators and crosslinking agents.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of solid-state electrolyte, in particular to a solid-state electrolyte precursor, a solid-state electrolyte and a preparation method thereof. BACKGROUND

[0002] In recent years, safety problems caused by electrolyte leakage have occurred frequently, and it is urgent to study solid-state electrolyte. However, the low ionic conductivity of the solid-state electrolyte and the difficulty in solving the solid-solid interface (the interface formed by solid phases, i.e. the interface between the solid-state electrolyte and the electrode and the interface between the solid-state electrolyte and the separator) have slowed down the development of the solid-state electrolyte, and the quasi-solid-state electrolyte has become the only way for the liquid-state electrolyte to become a solid-state electrolyte. Among them, the in-situ solidification technology has attracted widespread research by scientific researchers due to its simple process and easy industrialization.

[0003] However, the existing in-situ solidification uses a solid-state electrolyte precursor solution which needs to add a large amount of monomer, initiator and crosslinking agent to polymerize, resulting in a solid-state electrolyte with low ionic conductivity. SUMMARY

[0004] The purpose of the present disclosure is to provide a solid-state electrolyte precursor, a solid-state electrolyte and a preparation method thereof to solve the problems in the related art.

[0005] To achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0006] According to a first aspect of the embodiments of the present disclosure, a solid-state electrolyte precursor is provided, which comprises the following:

[0007] a mixed solvent, a lithium salt, a mesoporous material, a first compound and a second compound;

[0008] The lithium salt is selected from one or more of lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium bis(oxalato)borate, lithium difluoro(oxalato)borate, lithium methylsulfonate, lithium bis(pentafluoroethylsulfonylimide), lithium bis(trifluoromethylsulfonylimide) and lithium bis(fluorosulfonylimide);

[0009] The mass percentage of the lithium salt is selected from 3%-30% based on the total mass of the solid-state electrolyte precursor;

[0010] The mixed solvent comprises the following composition:

[0011] a component: an alcohol or ether solvent; the alcohol or ether solvent is selected from ethanol, isopropanol, n-butanol, tert-butanol, ethylene glycol, glycerol, dimethyl ether, ethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dioxane or diethyl ether;

[0012] b component: one or more of thionyl chloride, trimethylsulfoxonium bromide, sulfuryl chloride, thionyl bromide, fluorosulfuric acid, sulfuryl fluoride, 4-chlorophenyl sulfoxide, oxalyl chloride, and trichloroacetyl chloride;

[0013] Preferably, the mass percentage content of the mixed solvent is selected from 40%-90%, based on the total mass of the solid-state electrolyte precursor.

[0014] In an aspect of the embodiments of the present disclosure, preferably, the mass percentage content of the lithium salt is selected from 5%-15%, based on the total mass of the solid-state electrolyte precursor; specifically, the mass percentage content of the lithium salt is selected from 5.0%, 5.5%, 6.0%, 6.5%, 7.0%, 7.5%, 8.0%, 8.5%, 9.0%, 9.5%, 10.0%, 10.5%, 11.0%, 11.5%, 12.0%, 12.5%, 13.0%, 13.5%, 14.0%, 14.5%, 15.0%, but not limited thereto.

[0015] In an aspect of the embodiments of the present disclosure, in the mixed solvent, the mass ratio of the a component and the b component is selected from 1:(0.05-0.15).

[0016] In an aspect of the embodiments of the present disclosure, the mesoporous material is selected from SBA-15 molecular sieve, SBA-16 molecular sieve, MCM-41 molecular sieve, MCM-48 molecular sieve, mesoporous SiO2, mesoporous Al2O3, mesoporous TiO2, mesoporous ZrO2, mesoporous MgO, ordered mesoporous carbon CMK-3, or ordered mesoporous carbon CMK-8; and the mass percentage content of the mesoporous material is selected from 0.5%-10%, based on the total mass of the solid-state electrolyte precursor.

[0017] In an aspect of the embodiments of the present disclosure, preferably, the mass percentage content of the mesoporous material is selected from 3%-8%, based on the total mass of the solid-state electrolyte precursor; specifically, the mass percentage content of the mesoporous material is selected from 3.0%, 3.5%, 4.0%, 4.5%, 5.0%, 5.5%, 6.0%, 6.5%, 7.0%, 7.5%, or 8.0%.

[0018] In an aspect of the embodiments of the present disclosure, the first compound has the following structure represented by Formula I:

[0019]

[0020] wherein Ar1, Ar2, and Ar3 are each independently selected from substituted or unsubstituted C3-30 cycloalkyl, substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted 3-30 membered heterocyclyl, substituted or unsubstituted 5-30 membered heteroaryl;

[0021] R1, R2and R3are each independently selected from a direct bond, -NH-, -N=N-, -NH-NH-, -O-, -S-, substituted or unsubstituted C1-C30alkyl, substituted or unsubstituted C2-C30alkenyl, substituted or unsubstituted C2-C30alkynyl, substituted or unsubstituted C1-C30alkoxy.

[0022] In one aspect of the embodiments of the present disclosure, the first compound has the following structure represented by Formula I-A:

[0023]

[0024] wherein R1is selected from a direct bond, -NH-, -N=N-, -O-, -S-, substituted or unsubstituted C1-C10alkyl, substituted or unsubstituted C2-C10alkenyl, substituted or unsubstituted C2-C10alkynyl, substituted or unsubstituted C1-C10alkoxy.

[0025] In one aspect of the embodiments of the present disclosure, the second compound has the following structure represented by Formula II:

[0026]

[0027] wherein Ar4is selected from substituted or unsubstituted C3-30cycloalkyl, substituted or unsubstituted C6-C30aryl, substituted or unsubstituted 3-30 membered heterocyclyl, substituted or unsubstituted 5-30 membered heteroaryl;

[0028] R4and R5are each independently selected from a direct bond, -C(O)-, -NH-, -N=N-, -NH-NH-, -O-, -S-, substituted or unsubstituted C1-C30alkyl, substituted or unsubstituted C2-C30alkenyl, substituted or unsubstituted C2-C30alkynyl, substituted or unsubstituted C1-C30alkoxy;

[0029] n is selected from a natural number from 0 to 5; n R6s are the same or different from each other; R6is selected from amino, nitro, halogen atom, hydroxyl, carboxyl, cyano, substituted or unsubstituted C1-C10alkyl, substituted or unsubstituted C2-C10alkenyl, substituted or unsubstituted C2-C10alkynyl, substituted or unsubstituted C1-C10alkoxy.

[0030] In one aspect of the embodiments of the present disclosure, the second compound has the following structure represented by Formula II-A:

[0031]

[0032] wherein Ar4 is selected from substituted or unsubstituted C6-C12 aryl, substituted or unsubstituted 5-12 membered heteroaryl;

[0033] n is selected from 0, 1, 2 or 3; n R6s are the same or different from each other; R6 is selected from amino, nitro, halogen atom, hydroxyl, carboxyl, cyano, C1-C5 alkyl, C2-C5 alkenyl, C2-C5 alkynyl, C1-C5 alkoxy.

[0034] In an aspect of the embodiments of the present disclosure, the first compound is selected from the following compound I-1:

[0035]

[0036] The second compound is selected from any one of the following compounds II-1 to II-9:

[0037]

[0038]

[0039]

[0040] In an aspect of the embodiments of the present disclosure, the percentage content of the mass sum of the first compound and the second compound is selected from 15%-50%, based on the total mass of the solid-state electrolyte precursor.

[0041] In an aspect of the embodiments of the present disclosure, the ratio of the molar mass of the first compound and the second compound is selected from 1:(1.2-1.8); specifically, it can be 1:1.5.

[0042] According to a second aspect of the embodiments of the present disclosure, a solid-state electrolyte is provided, which is prepared from the aforementioned solid-state electrolyte precursor.

[0043] According to a third aspect of the embodiments of the present disclosure, a preparation method of the aforementioned solid-state electrolyte is provided, which comprises the following steps:

[0044] Step 1: providing the aforementioned solid-state electrolyte precursor;

[0045] Step 2: adding a catalyst glacial acetic acid to the solid-state electrolyte precursor, so that the first compound and the second compound are polymerized to form a framework type three-dimensional structure material, and after drying, the solid-state electrolyte is obtained.

[0046] In an aspect of the embodiments of the present disclosure, in step 2, heating is further required to make the first compound and the second compound polymerize; the heating temperature is selected from 50-80℃.

[0047] Compared with the prior art, the present disclosure has the following beneficial effects:

[0048] The solid-state electrolyte precursor prepared by the present disclosure is stable by itself, and can self-polymerize to form a framework three-dimensional structure material after the addition of a catalyst DMF, without the need for additional initiators and crosslinking agents, and the catalyst glacial acetic acid can also be volatilized in the subsequent drying process so as not to remain in the solid-state electrolyte. Moreover, the three-dimensional structure formed after the drying of the framework three-dimensional structure material can stabilize the structure of the solid-state electrolyte; in addition, (1) the three-dimensional topological pores or framework in the three-dimensional structure can connect the originally isolated ion migration "islands" into a network, shortening the effective diffusion path of Li⁺; (2) the three-dimensional structure can form a rigid skeleton, thereby constraining the growth of lithium dendrites and increasing the cycle life. DETAILED DESCRIPTION

[0049] For the purposes of the present application, the technical solutions and advantages thereof will be more clearly described below, and the technical solutions of the present application will be clearly and completely described with reference to the embodiments. Obviously, the described embodiments are only some of the embodiments of the present application, rather than all the embodiments. The embodiments described herein are illustrative in nature and serve to provide a basic understanding of the present application. The embodiments of the present application should not be interpreted as a limitation of the present application.

[0050] For the sake of brevity, only some numerical ranges are specifically disclosed herein. However, any lower limit can be combined with any upper limit to form a range not explicitly recited; and any lower limit can be combined with any other lower limit to form a range not explicitly recited, and likewise any upper limit can be combined with any other upper limit to form a range not explicitly recited. Further, each individual disclosed point or single numerical value can itself serve as a lower limit or upper limit to combine with any other point or single numerical value or to combine with other lower limits or upper limits to form a range not explicitly recited.

[0051] In the present disclosure, the term "alkyl" refers to an aliphatic hydrocarbon group, which can be straight-chained or branched. Branched refers to one or more lower alkyl groups, such as methyl, ethyl, or propyl, attached to a linear alkyl chain. "Lower alkyl" refers to a group containing from about 1 to about 6 carbon atoms in the chain, which can be straight-chained or branched.

[0052] In the present disclosure, the term "alkenyl" refers to an aliphatic hydrocarbon group containing at least one carbon-carbon double bond, which can be straight-chained or branched. Branched refers to one or more lower alkyl groups, such as methyl, ethyl, or propyl, attached to a linear alkenyl chain. "Lower alkenyl" refers to a group containing from about 2 to about 6 carbon atoms in the chain, which can be straight-chained or branched.

[0053] In the present disclosure, the term "alkynyl" refers to an aliphatic hydrocarbon group containing at least one carbon-carbon triple bond, which can be straight-chain or branched. Branched refers to one or more lower alkyl groups, such as methyl, ethyl, or propyl, attached to the linear alkynyl chain. "Lower alkynyl" refers to an alkynyl group containing from about 2 to about 6 carbon atoms, which can be straight-chain or branched. Non-limiting examples of alkynyl groups include ethynyl, propynyl, 2-butynyl, 3-methylbutynyl, n-pentynyl, and decynyl.

[0054] In the present disclosure, the term "aryl" refers to an aromatic monocyclic or polycyclic ring system. The aryl group can be optionally substituted with one or more "ring system substituents," which can be the same or different, as defined herein. Non-limiting examples of suitable aryl groups include phenyl and naphthyl.

[0055] In the present disclosure, the term "heteroaryl" refers to an aromatic monocyclic or polycyclic ring system in which one or more of the ring atoms is an element other than carbon, such as nitrogen, oxygen, or sulfur, alone or in combination. Preferred heteroaryls contain from about 5 to about 6 ring atoms. The "heteroaryl" group can be optionally substituted with one or more "ring system substituents," which can be the same or different, as defined herein. The prefix naphtho-, oxazepin-, thiazepin-, or oxazocin- before a heteroaryl group name indicates the presence of at least one nitrogen, oxygen, or sulfur atom, respectively, as a ring atom. The nitrogen atom of a heteroaryl group can optionally be oxidized to the corresponding N-oxide. Non-limiting examples of suitable heteroaryl groups include pyridyl, pyrazinyl, furanyl, thiophenyl, pyrimidinyl, isoxazolyl, isothiazolyl, oxazolyl, thiazolyl, pyrazolyl, furazanyl, pyrrolyl, pyrazolyl, triazolyl, 1,2,4-thiadiazolyl, pyrazinyl, pyridazinyl, quinoxalinyl, phthalazinyl, imidazo[l,2-a]pyridyl, imidazo[2,l-b]thiazolyl, benzofurazanyl, indolyl, azaindolyl, benzimidazolyl, benzothiophenyl, quinolinyl, imidazolyl, thienopyridyl, quinazolinyl, thienopyrimidinyl, pyrrolopyridyl, imidazopyridyl, isoquinolinyl, benzoazaindolyl, 1,2,4-triazinyl, benzothiazolyl, and the like.

[0056] In the present disclosure, the term "amino" refers to a -NR'R" group. The amino group can optionally be substituted. In an unsubstituted amino group, R' and R" are hydrogen. In a substituted amino group, R' and R" can each independently be, but are not limited to, hydrogen, alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, alkylcycloalkyl, alkylheterocycloalkyl, alkoxy, sulfonyl, alkenyl, alkylcarbonyl, aryl, arylalkyl, or heteroaryl, provided that R' and R" are not both hydrogen. In a substituted amino group, R' and R" can cyclize to form a cyclic amino group, such as pyrrolidinyl or piperidinyl. Such cyclic amino groups can incorporate additional heteroatoms, such as to form a piperazinyl or morpholinyl group. Such cyclic amino groups can optionally be substituted, such as with amino, hydroxy, or oxo.

[0057] In the present disclosure, the term "alkoxy" refers to -O-alkyl. Alkoxy can refer to straight-chained, branched, or cyclic, saturated or unsaturated oxy-hydrocarbon chains, including, for example, methoxy, ethoxy, propoxy, isopropoxy, butoxy, t-butoxy, and pentoxy. Alkoxy can be optionally substituted with one or more alkoxy substituents ("substituted alkoxy").

[0058] In the present disclosure, the term "cycloalkyl" refers to non-aromatic mono- or polycyclic ring systems, preferred cycloalkyl rings contain about 5 to about 7 ring atoms. Cycloalkyl can be optionally substituted with one or more "ring system substituents", which can be the same or different, are as defined above. Non-limiting examples of suitable monocyclic cycloalkyl groups include cyclopropyl, cyclopentyl, cyclohexyl, cycloheptyl, and the like. Non-limiting examples of suitable polycyclic cycloalkyl groups include 1-decalinyl, norbornyl, adamantyl, and the like. In the present disclosure, the term "cycloalkoxy" refers to a group in which one or more of the carbon atoms of a mono- or polycyclic ring system of "cycloalkyl" is replaced with an oxygen atom.

[0059] In the present disclosure, the term "heterocyclyl" refers to a non-aromatic saturated monocyclic or polycyclic ring system in which one or more of the ring atoms is an element other than carbon, such as nitrogen, oxygen, or sulfur, alone or in combination. There are no adjacent oxygen and / or sulfur atoms in the ring system, preferred heterocycles contain about 5 to about 6 ring atoms. The prefix n-, o-, or s- before a heterocyclyl group name indicates the presence of at least one nitrogen, oxygen, or sulfur atom, respectively, as a ring atom. Heterocyclyl can be optionally substituted with one or more "ring system substituents", which can be the same or different, are as defined herein. The nitrogen or sulfur atom of a heterocyclyl group can be optionally oxidized to the corresponding N-oxide, S-oxide, or S,S-dioxide. Non-limiting examples of suitable monocyclic heterocyclyl rings include piperidinyl, pyrrolidinyl, piperazinyl, morpholinyl, thiomorpholinyl, thiazolidinyl, 1,3-dioxolanyl, 1,4-dioxanyl, tetrahydrofuranyl, tetrahydrothiophenyl, tetrahydrothiopyranyl, and the like.

[0060] In the present disclosure, the second compound is prepared by the following steps (using the compound of Formula II-A as an example):

[0061] Step 1-a:

[0062]

[0063] Step 2-a:

[0064]

[0065] The present disclosure will be further illustrated by the following examples. It should be understood that these examples are for illustration only and do not limit the scope of the present disclosure.

[0066] Examples and Comparative Examples:

[0067] Example 1:

[0068] Example 1 includes the following steps:

[0069] 1. Preparation of compound II-1:

[0070] Take 16.71 g of pyridine-2,5-dicarboxylic acid (0.1 mol) and add to the reaction container, then add 120 mL of thionyl chloride as the reaction solvent, 2 mL of DMF as the catalyst, heat to reflux at 90°C for 12 h, after the reaction is completed, cool to room temperature, remove the remaining solvent by vacuum distillation, then slowly add 80 mL of methanol under ice bath conditions, heat to reflux for 6 h, then cool to room temperature, at this time a large amount of light yellow crystalline solid is precipitated, filter and vacuum dry to obtain the intermediate product, the reaction process is as follows:

[0071]

[0072] Add all the obtained intermediate products to the reaction container, then add excess hydrazine hydrate (40 mL) as the reaction solvent, heat to reflux at 60°C for 24 h, cool to room temperature, remove the solvent by rotary evaporation, and vacuum dry to obtain 16.01 g (0.082 mmol) of compound II-1, the reaction process is as follows:

[0073]

[0074] The above steps can be repeated multiple times to prepare sufficient compound II-1.

[0075] 2. Preparation of the solid-state electrolyte precursor of Example 1:

[0076] Take 10 parts by weight of lithium hexafluorophosphate as the lithium salt; dissolve 5 parts by weight of trimethylsilyl bromide in 55 parts by weight of ethylene glycol dimethyl ether as the mixed solvent; take 5 parts by weight of SBA-16 molecular sieve as the mesoporous material, take a total of 25 parts by weight of compound II-1 and compound I-1 (4,4,4-triformaldehyde triphenylamine, CAS: 119001-43-3, commercially available), and the molar ratio of compound I-1 to compound II-1 is 1:1.5. Mix the above components thoroughly to obtain the solid-state electrolyte precursor of Example 1.

[0077] Example 2:

[0078] The procedure of Example 2 is followed as in Example 1 except that equimolar amounts of terephthalic acid are used instead of pyridine-2,5-dicarboxylic acid as the reactant. In Example 2, compound II-2 having the following structure is obtained instead of compound II-1 in Example 1:

[0079]

[0080] Example 3:

[0081] The procedure of Example 3 is followed as in Example 1 except that equimolar amounts of 2,5-dimethyl terephthalic acid are used instead of pyridine-2,5-dicarboxylic acid as the reactant. In Example 3, compound II-3 having the following structure is obtained instead of compound II-1 in Example 1:

[0082]

[0083] Example 4:

[0084] The procedure of Example 4 is followed as in Example 1 except that equimolar amounts of 2,5-thiophene dicarboxylic acid are used instead of pyridine-2,5-dicarboxylic acid as the reactant. In Example 4, compound II-4 having the following structure is obtained instead of compound II-1 in Example 1:

[0085]

[0086] Example 5:

[0087] The procedure of Example 5 is followed as in Example 1 except that equimolar amounts of furan-2,5 dicarboxylic acid are used instead of pyridine-2,5-dicarboxylic acid as the reactant. In Example 5, compound II-5 having the following structure is obtained instead of compound II-1 in Example 1:

[0088]

[0089] Example 6:

[0090] The procedure of Example 6 is followed as in Example 1 except that equimolar amounts of pyrazine-2,5 dicarboxylic acid are used instead of pyridine-2,5-dicarboxylic acid as the reactant. In Example 6, compound II-6 having the following structure is obtained instead of compound II-1 in Example 1:

[0091]

[0092] Example 7:

[0093] The procedure of Example 7 and Example 1 is followed except that equimolar amounts of 2,6-naphthalene dicarboxylic acid is used instead of pyridine-2,5-dicarboxylic acid as the reactant. In Example 7, compound II-9 having the following structure is obtained instead of compound II-1 in Example 1:

[0094]

[0095] Performance stability test:

[0096] The samples of Example 1-7 are stored at room temperature in the dark for 21 days to observe whether the samples of Example 1-7 undergo self-polymerization without the addition of an additive; none of Example 1, Example 4, Example 5, Example 6, and Example 7 have precipitated solids, and Example 2 and Example 3 have a relatively large amount of precipitated solids.

[0097] Preparation of solid-state electrolyte and preparation of solid-state lithium battery:

[0098] In a glove box, a catalyst, glacial acetic acid, is added to the solid-state electrolyte precursor prepared in Example 1, the mixture is stirred, and the solution is cast onto a polytetrafluoroethylene plate, then scraped with a 200 μm doctor blade, and then left to stand in a vacuum environment at 60°C for 6 h of polymerization, and then dried at 80°C for 24 h in a vacuum to obtain the solid-state electrolyte of Example 1.

[0099] The -C(O)- of the first compound of Example 1 and the -NH-NH2 of the second compound are bonded to each other to form -C=N-NH-, thereby polymerizing to form a framework three-dimensional structure material.

[0100] The framework three-dimensional structure materials of Example 4, Example 5, and Example 6 are prepared according to the above procedure.

[0101] Preparation of positive electrode sheet: LiFeP04 is used as the active material, PVDF is used as the binder, and Super p is used as the conductive agent. The materials are weighed according to a ratio of 90wt% LiFeP04, 8% Super-p, and 2% PVDF, NMP is added as a dispersant, and the mixture is ground in a ball mill jar at 300 rpm for 2 hours. The slurry is coated on an aluminum foil using an automatic film coater, dried in an oven at 80°C for 6 h, and dried in a vacuum oven at 120°C for 12 h. The dried electrode sheet is cut into 10 mm round sheets using an electrode sheet cutter.

[0102] The solid-state lithium battery is composed of a positive electrode, a composite solid-state electrolyte, and a negative electrode, wherein the solid-state electrolyte is the composite solid-state electrolyte prepared in the above-mentioned embodiments 1, 4, 5, and 6. The assembly of the button cell: under an argon atmosphere, the positive electrode sheet, the composite solid-state electrolyte film, the lithium sheet, the gasket, and the spring are sequentially placed in the positive electrode shell, and then the negative electrode shell is buckled, and the battery is compressed with a packaging machine. After the prepared battery is taken out of the glove box, it is placed in an oven, and is repeatedly heat-treated from room temperature to 90°C for three times, so that the composite solid-state electrolyte and the positive and negative electrodes are tightly attached, and after standing for 12 h, the battery is tested.

[0103] Electrochemical test:

[0104] Coulomb efficiency test: at room temperature, constant current charging to the upper limit voltage 4.2V at 0.1C, constant voltage charging at 4.2V, cutoff current 0.05C, standing for 30 min, constant current discharging to 2.0V at 0.1C, the constant current charging capacity is recorded as C1, the constant voltage charging capacity is recorded as C2, and the constant current discharging capacity is recorded as C3; the coulomb efficiency = C3 / (C1+C2)*100%.

[0105] Discharge capacity test after 250 cycles:

[0106] At 60°C, the battery is left for 2h, constant current charging to the upper limit voltage 4.2V at 0.5C, constant voltage charging at 4.2V, cutoff current 0.05C, standing for 30 min, constant current discharging to 2.0V at 0.5C, and cycling for 250 cycles. Then the battery is left at room temperature for 2h, constant current charging to the upper limit voltage 4.2V at 0.1C, constant voltage charging at 4.2V, cutoff current 0.05C, standing for 30 min, constant current discharging to 2.0V at 0.1C, and the 0.1C constant current discharging capacity is recorded as the 250 cycle discharge capacity.

[0107] The results of the electrochemical test are shown in Table 1 below.

[0108] Table 1

[0109]

[0110] Compared with embodiments 4 and 5, embodiments 1 and 6 exhibit better electrochemical performance, because the two symmetrical sp2N atoms on the pyrazine ring have lone pair electrons, which can act as Lewis bases to form transient N···Li+coordination with Li+, thereby increasing the free Li+concentration; and the pyrazine ring has planar rigidity, forming a continuous “two-dimensional / three-dimensional ion channel”, thereby shortening the Li+migration distance.

[0111] The present disclosure is intended to embrace all such alternatives, modifications, and variations that fall within the broad scope of the appended claims. Accordingly, any and all such modifications, as will be apparent to those skilled in the art, may be made in the foregoing without departing from the spirit and scope of the disclosure including the nomenclature used.

Claims

1. A solid-state electrolyte precursor, characterized by, The solid-state electrolyte precursor comprises The following: a mixed solvent, a lithium salt, a mesoporous material, a first compound, and a second compound; The lithium salt is selected from one or more of lithium hexafluorophosphate, lithium perchlorate, lithium tetrafluoroborate, lithium bis(oxalato)borate, lithium difluoro(oxalato)borate, lithium methylsulfate, lithium bis(pentafluoroethylsulfonimide), lithium bis(trifluoromethylsulfonimide), and lithium bis(fluorosulfonimide); The mass percentage of the lithium salt is selected from 3%-30%, based on the total mass of the solid-state electrolyte precursor; The mixed solvent comprises the following components: a component: an alcohol or ether solvent; the alcohol or ether solvent is selected from ethanol, isopropanol, n-butanol, t-butanol, ethylene glycol, glycerol, dimethyl ether, ethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dioxane, or diethyl ether; a component: one or more of sulfurous chloride, trimethylsulfonium bromide, sulfonium bromide, sulfonium fluoride, sulfuryl chloride, sulfonyl fluoride, sulfonyl bromide, 4-chlorophenyl sulfide, oxalyl chloride, and trichloroacetyl chloride; The mass percentage of the mixed solvent is selected from 40%-90%, based on the total mass of the solid-state electrolyte precursor; The first compound is selected from the following compound I-1: The second compound is selected from any one of the following compounds II-1 to II-9: 。 2. The solid-state electrolyte precursor of claim 1, wherein, The mesoporous material is selected from SBA-15 molecular sieve, SBA-16 molecular sieve, MCM-41 molecular sieve, MCM-48 molecular sieve, mesoporous SiO2, mesoporous Al2O3, mesoporous TiO2, mesoporous ZrO2, mesoporous MgO, ordered mesoporous carbon CMK-3, or ordered mesoporous carbon CMK-8; The mass percentage of the mesoporous material is selected from 0.5%-10%, based on the total mass of the solid-state electrolyte precursor.

3. The solid-state electrolyte precursor of claim 1, wherein, The percentage content of the mass sum of the first compound and the second compound is selected from 15%-50%, based on the total mass of the solid-state electrolyte precursor; The molar ratio of the first compound to the second compound is selected from 1:(1.2-1.8).

4. A solid state electrolyte, characterized by, The solid-state electrolyte is prepared from the solid-state electrolyte precursor of any one of claims 1-3.

5. The method of producing a solid-state electrolyte according to claim 4, characterized by, The preparation method comprises the following steps: Step 1: providing a solid-state electrolyte precursor; Step 2: adding a catalyst, glacial acetic acid, to the solid-state electrolyte precursor, so that the first compound and the second compound are polymerized to form a framework three-dimensional structure material, and the solid-state electrolyte is obtained after drying.

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