Solid-state electrolyte precursor solution, solid-state electrolyte membrane, and solid-state battery

Abstract

The invention relates to the technical field of solid-state batteries, in particular to a solid-state electrolyte precursor solution, a solid-state electrolyte membrane and a solid-state battery. The solid electrolyte precursor solution is mainly prepared from a polymer monomer, a mesoporous material, an organic solvent, an initiator and a lithium salt; the polymer monomer comprises an unsaturated amide monomer and an unsaturated boric acid ester monomer; the structural formula of the unsaturated amide monomer is shown as a general formula (I); the structural formula of the unsaturated boric acid ester monomer is shown as a general formula (II); # imgabs0 # (I); and # imgabs1 # (II). The supramolecular solid electrolyte material is designed, the mesoporous material is introduced to increase the specific surface area of lithium conduction of an interface, meanwhile, coordination with lithium ions can be formed through contained special groups, migration of the lithium ions is promoted, and the electrolyte membrane has high ionic conductivity.

Description

Technical Field

[0001] The present invention relates to the technical field of solid-state batteries, and in particular to a solid-state electrolyte precursor solution, a solid-state electrolyte membrane and a solid-state battery. Background Art

[0002] Traditional lithium-ion batteries use graphite negative electrodes, which have low energy density and can no longer meet current needs. Using lithium metal (theoretical capacity 3860mAh / g) as the negative electrode can effectively increase the battery energy density. However, due to the active reducibility of lithium metal and the easy diffusion of traditional electrolytes, the interface reaction continues, resulting in a continuous increase in interface resistance and a large consumption of lithium metal and electrolyte. In addition, organic electrolytes are volatile and flammable, which poses a huge safety hazard when the battery overheats.

[0003] In recent years, with the increasing demand for energy storage and the high attention to battery safety, the research on solid electrolytes has developed rapidly. Researchers continue to explore new material systems and improve preparation processes to improve the performance of solid electrolytes, making it gradually become a research hotspot in the battery field. The use of solid electrolytes with low diffusivity can maintain stable interface contact with the lithium metal negative electrode, and the thermal stability of solid electrolytes is higher, which can ensure the safety of the battery while improving the energy density.

[0004] At present, solid electrolytes are mainly divided into two categories: organic and inorganic. Compared with inorganic ceramic electrolytes, organic polymer solid electrolytes have better flexibility and ductility. On the one hand, they can maintain close contact with the electrode, adapt to the volume change of the electrode during the cycle, and inhibit the formation of lithium dendrites; on the other hand, they can promote the preparation of ultra-thin electrolyte membranes, reduce the volume of batteries, and make them closer to practical application. Secondly, although polymer electrolytes can inhibit lithium dendrites to a certain extent, this phenomenon is still unavoidable. Summary of the invention

[0005] In order to solve the above problems in the prior art, the present invention provides a solid electrolyte precursor solution, a solid electrolyte membrane and a solid-state battery. By designing a supramolecular solid electrolyte material, a mesoporous material is introduced to increase the specific surface area of ​​interfacial lithium conduction. At the same time, the special groups contained in the material can form coordination with lithium ions to promote the migration of lithium ions, so that the electrolyte membrane has high ionic conductivity.

[0006] Based on this, the present invention has the following technical solutions: In a first aspect, the present invention provides a solid electrolyte precursor solution, wherein the solid electrolyte precursor solution is mainly prepared from a polymer monomer, a mesoporous material, an organic solvent, an initiator and a lithium salt; the polymer monomer comprises an unsaturated amide monomer and an unsaturated borate monomer; the structural formula of the unsaturated amide monomer is shown in general formula (I); the structural formula of the unsaturated borate monomer is shown in general formula (II); (I); (II); Wherein, R1 and R3 are each independently, the same or different, an ester group, a C2-C6 substituted or unsubstituted alkenyl group, or a C6-C 30 or, a group consisting of any of the above groups, wherein R2, R4 and R5 are each independently, the same or different from each other, an H atom, a keto group, a hydroxyl group, an amine group, an amide group, a C1-C6 substituted or unsubstituted alkyl group, a C1-C6 substituted or unsubstituted alkoxy group, a C2-C6 substituted or unsubstituted alkenyl group or a C6-C 30 A substituted or unsubstituted aryl group, or a group consisting of any of the above groups.

[0007] The applicant has found that adding mesoporous materials can not only provide more pores to accommodate small molecule monomers and increase the specific surface area for lithium conduction, but also can act as an inorganic filler to reduce the crystallinity of polymers. The copolymerization of borate small molecules and amide monomers can be stacked to form supramolecular bodies of polymer chains or network structures. The intermolecular BN coordination drives the self-assembly of primitives, and can also form coordination with metal lithium ions to promote lithium conduction. At the same time, the borate bond has dynamic reversibility, and the prepared material has a self-repairing function, that is, when the material is damaged, the borate bond can be reformed under certain conditions to achieve self-repair of the material, excellent mechanical properties, and extend the service life of the material, thereby increasing the cycle life of the battery.

[0008] In the present invention, the mesoporous material refers to a material having a regularly arranged, size-adjustable pore structure, a high specific surface area and a large adsorption capacity, and the pore size is generally between 2 and 50 nm.

[0009] In the present invention, when the substituted or unsubstituted alkenyl and substituted or unsubstituted aryl in R1 and R3 are substituted, it means that one or more hydrogen atoms are replaced by the following substituents: electron-withdrawing groups such as fluorine atoms, chlorine atoms, and cyano groups.

[0010] In the present invention, when the substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted alkenyl and substituted or unsubstituted aryl in R2, R4 and R5 are substituted, it means that one or more hydrogen atoms are replaced by the following substituents: small steric hindrance groups such as methyl and ethyl or electron-withdrawing groups such as halogen atoms.

[0011] More preferably, R1 and R3 are each independently, the same or different, an ester group, a C2-C4 substituted or unsubstituted alkenyl group, or a C6-C 12 or, a group consisting of any of the above groups, wherein R2, R4 and R5 are each independently, the same or different from each other, an H atom, a keto group, a hydroxyl group, an amine group, an amide group, a C1-C3 substituted or unsubstituted alkyl group, a C1-C3 substituted or unsubstituted alkoxy group, a C2-C4 substituted or unsubstituted alkenyl group or a C6-C 12 A substituted or unsubstituted aryl group, or a group consisting of any of the above groups.

[0012] Preferably, the molar ratio of the unsaturated amide monomer to the unsaturated borate ester monomer is (4-6): (6-4).

[0013] More preferably, the molar ratio of the unsaturated amide monomer to the unsaturated borate ester monomer is (1-2):(1-2); further preferably, the molar ratio of the unsaturated amide monomer to the unsaturated borate ester monomer is 1:1.

[0014] Preferably, the unsaturated amide monomer includes one or more of N-isopropyl methacrylamide, N-methoxymethyl-2-methyl-2-acrylamide, diacetone acrylamide, N-(hydroxymethyl) acrylamide, N-benzyl acrylamide, dimethylaminopropyl acrylamide, N-phenyl methacrylamide, N-phenyl acrylamide and N,N-methylenebisacrylamide; And / or, the unsaturated borate monomer includes: one or more of allyl boronic acid pinacol ester, (4-vinylphenyl) boronic acid pinacol ester, 1-phenylvinyl boronic acid pinacol ester, diisopropyl boronic acid propenyl ester, 2-methyl-1-propenyl boronic acid pinacol ester, isopropenyl boronic acid pinacol ester and 3-acetoxy-1-propenyl boronic acid pinacol ester.

[0015] More preferably, the polymer monomers consist of the unsaturated amide monomers and the unsaturated borate ester monomers; further preferably, the polymer monomers consist of N-isopropyl methacrylamide and allyl boric acid pinacol ester.

[0016] Preferably, the mesoporous material includes one or more of SBA15, SBA16, MCM-41, MCM-48 and MCM50.

[0017] Preferably, the pore size of the mesoporous material is 2~40nm, preferably 5~30nm; for example, the pore size of the mesoporous material can be 5nm, 6nm, 7nm, 8nm, 9nm, 10nm, 11nm, 12nm, 13nm, 14nm, 15nm, 16nm, 17nm, 18nm, 19nm, 20nm, 21nm, 22nm, 23nm, 24nm, 25nm, 26nm, 27nm, 28nm, 29nm or 30nm.

[0018] Preferably, the amount of the mesoporous material added is 5wt%~30wt% of the total mass of the polymer monomer, preferably 10wt%~20wt%; for example, it can be 10wt%, 11wt%, 12wt%, 13wt%, 14wt%, 15wt%, 16wt%, 17wt%, 18wt%, 19wt% or 20wt%.

[0019] The present invention has found that when the amount of the mesoporous material added exceeds the above range, the polymerization reaction is affected, while when the amount added is lower than the above range, the amount of pores provided is insufficient and the effect is not obvious.

[0020] Preferably, the lithium salt includes one or more of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis(trifluoromethylsulfonyl)imide, lithium bis(fluorosulfonyl)imide, lithium bis(oxalatoborate), lithium difluorooxalatoborate and lithium trifluoromethanesulfonate.

[0021] More preferably, the amount of the lithium salt added is 30wt% to 65wt% of the total mass of the polymer monomer; the present invention finds that when the amount of the lithium salt added is lower than the above range, the measured ion conductivity will be seriously low; when the amount of the lithium salt added is higher than the above range, the polymer is difficult to form a film, preferably 45wt% to 60wt%; for example. It can be 45wt%, 46wt%, 47wt%, 48wt%, 49wt%, 50wt%, 51wt%, 52wt%, 53wt%, 54wt%, 55wt%, 56wt%, 57wt%, 58wt%, 59wt% or 60wt%.

[0022] Preferably, the organic solvent comprises one or more of diethyl ether, ethanol, acetonitrile, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, tetrahydrofuran, malononitrile, succinonitrile, glutaronitrile, adiponitrile, pimelonitrile, suberonitrile, azelaic acid dinitrile and sebacononitrile.

[0023] Preferably, the initiator includes one or more of azobisisobutyronitrile (AIBN), azobisisoheptanenitrile, dibenzoyl peroxide, diethylhexyl peroxydicarbonate, sodium persulfate and potassium persulfate.

[0024] As a preferred embodiment of the present invention, the solid electrolyte precursor solution is prepared from a polymer monomer, a mesoporous material, an organic solvent, an initiator and a lithium salt, wherein the mesoporous material is SBA15, the organic solvent is N,N-dimethylformamide, the polymer monomer is composed of an unsaturated amide monomer and an unsaturated borate monomer, the unsaturated amide monomer is N-isopropyl methacrylamide, the unsaturated borate monomer is allyl boric acid pinacol ester, the initiator is azobisisobutyronitrile, and the lithium salt is LiTFSI.

[0025] In a second aspect, the present invention provides a method for preparing the solid electrolyte precursor solution, comprising: S1: mixing the mesoporous material, the organic solvent, the polymer monomer and the initiator to obtain a mixed solution; S2: heating the mixed solution at 60-70° C. for 3-5 h, then adding lithium salt, and stirring at 20-30° C. for 7-10 h to obtain the solid electrolyte precursor solution.

[0026] The present invention finds that adding lithium salt to S1 will occupy the channels of the mesoporous material, so adding lithium salt after polymerization is more conducive to improving the ionic conductivity of the electrolyte membrane.

[0027] In a third aspect, the present invention provides a solid electrolyte membrane, comprising a solid electrolyte membrane prepared by a solution coating method using the solid electrolyte precursor solution.

[0028] In the present invention, the solid-state battery further comprises a positive electrode and a negative electrode, and the solid electrolyte membrane is arranged between the positive electrode and the negative electrode.

[0029] In a fourth aspect, the present invention provides a solid-state battery comprising the solid-state electrolyte film.

[0030] The solid electrolyte precursor solution, solid electrolyte membrane and solid-state battery provided by the present invention design a supramolecular solid electrolyte material, introduce a mesoporous material to increase the specific surface area of ​​interfacial lithium conduction, and at the same time, through the special groups contained in it, can form coordination with lithium ions to promote the migration of lithium ions, so that the electrolyte membrane has high ionic conductivity. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described clearly and completely below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Unless otherwise specified, the various raw materials used in the examples and comparative examples are commercially available conventional raw materials, and the technical means used are conventional means well known to those skilled in the art. In the following examples, the pore size of the mesoporous material is 5-30 nm.

[0033] Example 1 This embodiment provides a solid electrolyte precursor solution, and the preparation method thereof comprises the following steps: 0.885g SBA15 was added to a conical flask, and 60ml DMF was added and stirred evenly, followed by 2.54g N-isopropylmethacrylamide, 3.36g allylboronic acid pinacol ester and 0.04g initiator azobisisobutyronitrile (AIBN) and continued stirring until a homogeneous solution was obtained, and then heated to 65°C for 4h. Then 2.4g LiTFSI was added and stirred at room temperature for 8h to form a uniform mixed solution, which was the solid electrolyte precursor solution.

[0034] The polymer monomer is composed of an unsaturated amide monomer N-isopropyl methacrylamide and an unsaturated borate monomer allyl boric acid pinacol ester in a molar ratio of 1:1.

[0035] This embodiment also provides a solid electrolyte membrane, and the preparation method thereof comprises the following steps: The solid electrolyte precursor solution was coated on a polytetrafluoroethylene plate by a solution coating method. After drying overnight in a vacuum drying oven at 75°C, the film was peeled off from the glass plate and cut into a Φ16 mm circular polymer solid electrolyte membrane.

[0036] Example 2 This embodiment provides a solid electrolyte precursor solution, which is different from Embodiment 1 only in that the polymer monomer is composed of an unsaturated amide monomer N-(hydroxymethyl) acrylamide and an unsaturated borate monomer 1-phenylvinyl pinacol boronic acid ester in a molar ratio of 1:1.

[0037] This embodiment also provides a solid electrolyte membrane, which has the same preparation method as that of embodiment 1.

[0038] Example 3 This embodiment provides a solid electrolyte precursor solution, which is different from Embodiment 1 only in that the polymer monomer is composed of an unsaturated amide monomer N-phenylmethyl acrylamide and an unsaturated borate monomer isopropenyl boric acid pinacol ester in a molar ratio of 1:1.

[0039] This embodiment also provides a solid electrolyte membrane, which is prepared in the same manner as in embodiment 1. This embodiment provides a solid electrolyte precursor solution, which is different from Embodiment 1 only in that the polymer monomer is composed of an unsaturated amide monomer N-isopropyl methacrylamide and an unsaturated borate monomer allyl boric acid pinacol ester in a molar ratio of 4:6.

[0040] This embodiment also provides a solid electrolyte membrane, which is prepared in the same manner as in embodiment 1. This embodiment provides a solid electrolyte precursor solution, which is different from Embodiment 1 only in that the polymer monomer is composed of an unsaturated amide monomer N-isopropyl methacrylamide and an unsaturated borate monomer allyl boric acid pinacol ester in a molar ratio of 3:7.

[0041] This embodiment also provides a solid electrolyte membrane, which is prepared in the same manner as in embodiment 1. This embodiment provides a solid electrolyte precursor solution, and the preparation method thereof is different from that of Embodiment 1 only in that DMF is replaced by an equal amount of tetrahydrofuran, AIBN is replaced by an equal amount of dibenzoyl peroxide, and LiTFSI is replaced by an equal amount of lithium hexafluorophosphate.

[0042] This embodiment also provides a solid electrolyte membrane, which is prepared in the same manner as in embodiment 1. This embodiment provides a solid electrolyte precursor solution, and the preparation method thereof is different from that of Embodiment 1 only in that SBA15 is replaced by an equal amount of SBA16.

[0043] This embodiment also provides a solid electrolyte membrane, which is prepared in the same manner as in embodiment 1. This embodiment provides a solid electrolyte precursor solution, and the preparation method thereof is different from that of Embodiment 1 only in that SBA15 is replaced by an equal amount of MCM-41.

[0044] This embodiment also provides a solid electrolyte membrane, which is prepared in the same manner as in embodiment 1. This embodiment provides a solid electrolyte precursor solution, and the preparation method thereof is different from that of Embodiment 1 only in that the addition amount of SBA15 is 0.59 g.

[0045] This embodiment also provides a solid electrolyte membrane, which is prepared by the same method as in embodiment 1. This embodiment provides a solid electrolyte precursor solution, and the preparation method thereof is different from that of Embodiment 1 only in that the addition amount of SBA15 is 1.475 g.

[0046] This embodiment also provides a solid electrolyte membrane, which has the same preparation method as that of embodiment 1.

[0047] Embodiment 11 This embodiment provides a solid electrolyte precursor solution, and the preparation method thereof is different from that of embodiment 1 in that a lithium salt is added before the reaction, and the specific reaction steps include: Add 0.885g SBA15 to a conical flask, add 60ml DMF and stir evenly, then add 2.54g N-isopropyl methacrylamide and 3.36 allyl boric acid pinacol ester, 0.04g initiator AIBN and 2.4g LiTFSI and continue stirring until a homogeneous solution is obtained, and then heat to 65°C for 4h to form a uniform mixed solution, which is a solid electrolyte precursor solution. The polymer monomer is composed of an unsaturated amide monomer N-isopropyl methacrylamide and an unsaturated boric acid ester monomer allyl boric acid pinacol ester in a molar ratio of 1:1.

[0048] Comparative Example 1 This comparative example provides a solid electrolyte precursor solution, and the preparation method thereof is different from that of Example 1 only in that the unsaturated borate monomer allyl boronic acid pinacol ester is replaced by an equal amount of hexafluorobutyl acrylate.

[0049] This comparative example also provides a solid electrolyte membrane, which is prepared in the same manner as in Example 1.

[0050] Comparative Example 2 This comparative example provides a solid electrolyte precursor solution, and the preparation method thereof is different from that of Example 1 only in that the unsaturated borate ester monomer allyl boronic acid pinacol ester is replaced by an equal amount of unsaturated amide monomer N-isopropyl methacrylamide.

[0051] This comparative example also provides a solid electrolyte membrane, which is prepared in the same manner as in Example 1.

[0052] Test example The present invention further assembles the solid electrolyte membranes in the embodiments and comparative examples into solid lithium metal batteries, and tests their electrochemical properties. The results are shown in Table 1: Assembly and testing methods include: 1. Ionic conductivity: The polymer solid electrolyte membrane (CSEs) prepared above was combined with two stainless steel electrodes (SS) to form a SS / CSEs / SS simulated battery for testing. The battery assembly process was carried out in a glove box where the water and oxygen content was less than 0.1 ppm. The electrochemical impedance spectroscopy (EIS) test used a frequency range of 0.01 Hz to 106 Hz to measure the electrochemical impedance of the polymer solid electrolyte at room temperature. The impedance data obtained from the EIS test was used to calculate the ionic conductivity of the prepared polymer solid electrolyte.

[0053] 2. Cyclic stability: The polymer solid electrolyte sheets (CSEs) prepared above are combined with ternary positive electrodes and lithium metal negative electrodes to form button cells. The preparation of the cells is carried out in a glove box. The cells are tested for charge and discharge cycles at a rate of 0.1C, and the attenuation of their discharge capacity is detected.

[0054] Table 1

[0055] The experimental results show that when other unsaturated amide monomers or unsaturated borate monomers defined in the present invention are used in Examples 2-3, the effect is equivalent to that of Example 1. When the amount ratio of the unsaturated amide monomer or unsaturated borate monomer is (1-2): (1-2) in Examples 4-5 compared with Example 1, it is more conducive to improving the electrochemical performance of the battery. When the mesoporous materials, solvents, initiators and lithium salts other than those defined in Example 1 are used in Examples 6-8 compared with Example 1, the effect is slightly worse than that of Example 1, which proves that the mesoporous materials, solvents, initiators and lithium salts described in Example 1 can better cooperate with the unsaturated amide monomers or unsaturated borate monomers defined in the present invention, which helps to improve the comprehensive performance of the battery. Compared with Example 1, it can be seen from Examples 9-10 that when the amount of the mesoporous material is within the range defined in the present invention, the effect is equivalent to that of Example 1; and when the amount of the mesoporous material exceeds the range defined in the present invention, the ionic conductivity and cycle performance of the battery are slightly worse. Compared with Example 1, Example 11 shows that when lithium salt is added before the reaction, the lithium salt will occupy the channels of the mesoporous material, so the effect is worse than that of Example 1. Compared with Example 1, when the polymer monomer is a combination of a nitrogen-containing monomer and a fluorine-containing monomer or a polymer monomer such as an unsaturated amide monomer is used, the ion conductivity is too low and the cycle cannot reach 30 cycles.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A solid electrolyte precursor solution, characterized in that: The solid electrolyte precursor solution is prepared from polymer monomers, mesoporous materials, organic solvents, initiators and lithium salts; the polymer monomers include unsaturated amide monomers and unsaturated borate monomers; the structural formula of the unsaturated amide monomer is shown in general formula (I); the structural formula of the unsaturated borate monomer is shown in general formula (II); (AND); (II)); Wherein, R1 and R3 are each independently, the same or different, an ester group, a C2-C6 substituted or unsubstituted alkenyl group, or a C6-C 30 or, a group consisting of any of the above groups, wherein R2, R4 and R5 are each independently, the same or different from each other, an H atom, a keto group, a hydroxyl group, an amine group, an amide group, a C1-C6 substituted or unsubstituted alkyl group, a C1-C6 substituted or unsubstituted alkoxy group, a C2-C6 substituted or unsubstituted alkenyl group or a C6-C 30 A substituted or unsubstituted aryl group, or a group consisting of any of the above groups.

2. The solid electrolyte precursor solution according to claim 1, characterized in that The molar ratio of the unsaturated amide monomer to the unsaturated borate ester monomer is (4-6): (6-4).

3. The solid electrolyte precursor solution according to claim 1 or 2, characterized in that: The unsaturated amide monomers include one or more of N-isopropyl methacrylamide, N-methoxymethyl-2-methyl-2-acrylamide, diacetone acrylamide, N-(hydroxymethyl) acrylamide, N-benzyl acrylamide, dimethylaminopropyl acrylamide, N-phenyl methacrylamide, N-phenyl acrylamide and N,N-methylene bis acrylamide; And / or, the unsaturated borate monomer includes: one or more of allyl boronic acid pinacol ester, (4-vinylphenyl) boronic acid pinacol ester, 1-phenylvinyl boronic acid pinacol ester, diisopropyl boronic acid propenyl ester, 2-methyl-1-propenyl boronic acid pinacol ester, isopropenyl boronic acid pinacol ester and 3-acetoxy-1-propenyl boronic acid pinacol ester.

4. The solid electrolyte precursor solution according to any one of claims 1 to 3, characterized in that: The mesoporous material includes one or more of SBA15, SBA16, MCM-41, MCM-48 and MCM50.

5. The solid electrolyte precursor solution according to any one of claims 1 to 4, characterized in that: The pore size of the mesoporous material is 2-40 nm, preferably 5-30 nm.

6. The solid electrolyte precursor solution according to any one of claims 1 to 5, characterized in that: The amount of the mesoporous material added is 5wt% to 30wt% of the total mass of the polymer monomer, preferably 10wt% to 20wt%.

7. The solid electrolyte precursor solution according to any one of claims 1 to 6, characterized in that: The lithium salt includes one or more of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium bis(trifluoromethylsulfonyl)imide, lithium bis(fluorosulfonyl)imide, lithium bis(oxalate)borate, lithium difluorooxalateborate and lithium trifluoromethanesulfonate; And / or, the organic solvent comprises one or more of diethyl ether, ethanol, acetonitrile, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, tetrahydrofuran, malononitrile, succinonitrile, glutaronitrile, adiponitrile, pimelonitrile, suberonitrile, azelaic acid dinitrile and sebacononitrile; And / or, the initiator includes one or more of azobisisobutyronitrile, azobisisoheptylnitrile, dibenzoyl peroxide, diethylhexyl peroxydicarbonate, sodium persulfate and potassium persulfate.

8. The method for preparing a solid electrolyte precursor solution according to any one of claims 1 to 7, characterized in that: include: S1: mixing the mesoporous material, the organic solvent, the polymer monomer and the initiator to obtain a mixed solution; S2: heating the mixed solution at 60-70° C. for 3-5 h, then adding lithium salt, and stirring at 20-30° C. for 7-10 h to obtain the solid electrolyte precursor solution.

9. A solid electrolyte membrane, characterized in that: The method comprises preparing a solid electrolyte membrane by a solution coating method using the solid electrolyte precursor solution according to any one of claims 1 to 7.

10. A solid-state battery, characterized in that: A solid electrolyte film according to claim 9.

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