Semi-solid-state battery electrolyte precursor, semi-solid-state battery electrolyte, and semi-solid-state battery and preparation method therefor

Abstract

Provided are a semi-solid-state battery electrolyte precursor, a semi-solid-state battery electrolyte, and a semi-solid-state battery and a preparation method therefor. The electrolyte precursor comprises: a first polymer monomer, a second polymer monomer, and an initiator; the first polymer monomer is an acrylic monomer or an acrylate monomer; and the second polymer monomer is a fluorine-containing unsaturated monomer.

Description

Semi-solid battery electrolyte precursor, semi-solid battery electrolyte, semi-solid battery and preparation method thereof

[0001] This application claims priority to the Chinese patent application No. 2024112817445 filed on September 12, 2024 with the China Patent Office, the whole content of the above application is incorporated herein by reference. TECHNICAL FIELD

[0002] Lithium-ion batteries have been widely used in electronic products and electric vehicles. Although great achievements have been made in high energy density battery systems, electrolyte leakage, battery short circuit and other situations are still a great safety hazard, which seriously hinders the further development of lithium-ion batteries. When there is internal or external short circuit, the poor exothermic reaction can cause the internal temperature to rise rapidly and thermal runaway.

[0003] The solid-state battery is proposed to improve and replace the traditional liquid electrolyte, and fundamentally solve the safety situation. In the all-solid-state battery, a thermally stable solid-state polymer electrolyte or inorganic solid-state electrolyte is used instead of a liquid electrolyte, which helps to avoid electrolyte leakage and combustion explosion. BACKGROUND

[0004] Battery pack is an important part of new energy technology, which can provide energy and power for electrical equipment. The battery pack on the market is generally composed of multiple battery cells in series and / or parallel connection, and equipped with single battery monitoring and thermal management device. TECHNICAL PROBLEM

[0005] However, the all-solid-state battery still has some situations, such as poor contact between the electrolyte and the electrode, and lack of scalable preparation technology. In order to solve these challenges of all-solid-state batteries, constructing semi-solid-state batteries through in-situ polymerization technology is considered to be one of the most promising solutions to improve the safety performance of lithium-ion batteries. Gel electrolyte combines the advantages of liquid electrolyte and solid polymer electrolyte, and has good ionic conductivity and interface compatibility. In the lithium-ion battery, the gel electrolyte can adjust the uniform distribution of lithium ion flow, inhibit the decomposition reaction of the electrolyte, improve the electrode stability and the safety of the battery. The semi-solid-state battery prepared by using gel electrolyte has high safety and high energy density, and has great development potential compared with traditional liquid batteries.

[0006] In-situ polymerization process is a method for preparing semi-solid batteries. It has broad development prospects because it is compatible with related battery preparation processes and does not require changes to a large number of processes to achieve mass production. The semi-solid battery prepared by in-situ polymerization has a high DCIR compared with the liquid system because the monomer polymerization degree is difficult to control, the initiator residue causes more interface side reactions, and the like. The related process usually uses a precursor solution to inject liquid, perform formation, and then solidify at high temperature, so that the polymerized monomer participates in the SEI film formation during the formation stage, forming an interface with high impedance. The process route is optimized, the precursor solution is injected, high-temperature solidification is performed first, and then formation is performed, but the initial DCIR of the battery is still high. This is mainly because the high-temperature solidification stage consumes the film-forming additive containing unsaturated bonds, and the monomer is not completely polymerized, resulting in residue. The residual monomer may participate in the SEI film formation during the subsequent formation stage, thereby increasing the DCIR of the battery. There have been reports of process improvements to improve the DCIR of gel semi-solid batteries through secondary injection. The first injection is a liquid electrolyte, and the second injection is a mixed solution of electrolyte, monomer, and initiator after formation. Although this method can reduce the DCIR of the battery to some extent, it increases the complexity of the process and the time cost. Technical solutions

[0007] In a first aspect, the present application provides a semi-solid battery electrolyte precursor, which comprises: a first polymer monomer, a second polymer monomer, and an initiator; wherein the first polymer monomer is an acrylic monomer or an acrylate monomer; and the second polymer monomer is an unsaturated monomer containing fluorine.

[0008] In a second aspect, the present application provides a semi-solid battery electrolyte obtained by in-situ polymerization of any one of the semi-solid battery electrolyte precursors described above.

[0009] In a third aspect, the present application provides a preparation method of a semi-solid battery, which comprises: injecting any one of the semi-solid battery electrolyte precursors described above into a battery cell for in-situ polymerization.

[0010] In a fourth aspect, the present application provides a semi-solid battery prepared by any one of the preparation methods of the semi-solid battery described above or comprising the semi-solid battery electrolyte described above. Advantages

[0011] The application provides the following beneficial effects: the semi-solid battery electrolyte precursor of the application selects the first polymer monomer with the acrylic acid or acrylate structure and the second polymer monomer with the unsaturated structure containing fluorine, and the copolymer formed can improve the stability of the electrode / electrolyte interface. Even if there is monomer residue, an SEI film with good stability can be formed in the subsequent film forming stage, and the electrode / electrolyte interface is optimized. At the same time, the semi-solid battery electrolyte precursor of the application has a large number of monomer types, can design different electrolyte systems according to the battery requirements, and the subsequent preparation process for the semi-solid battery is simple. While significantly reducing the direct current internal resistance (DCIR), the preparation efficiency of the battery can be improved, and the application has good scalability.

[0012] Embodiments of the application

[0013] As analyzed in the background of the application, the interface performance of the semi-solid battery in the related art is unstable and the battery impedance is high. In order to solve this problem, the application provides a semi-solid battery electrolyte precursor, a semi-solid battery electrolyte, a semi-solid battery and a preparation method thereof.

[0014] According to a typical embodiment of the application, a semi-solid battery electrolyte precursor is provided, which comprises: a first polymer monomer, a second polymer monomer and an initiator; the first polymer monomer is an acrylic monomer or an acrylate monomer; and the second polymer monomer is an unsaturated monomer containing fluorine.

[0015] The semi-solid battery electrolyte precursor of the application selects the first polymer monomer with the acrylic acid or acrylate structure and the second polymer monomer with the unsaturated structure containing fluorine, and the copolymer formed can improve the stability of the electrode / electrolyte interface. Even if there is monomer residue, an SEI film with good stability can be formed in the subsequent film forming stage, and the electrode / electrolyte interface is optimized. At the same time, the semi-solid battery electrolyte precursor of the application has a large number of monomer types, can design different electrolyte systems according to the battery requirements, and the subsequent preparation process for the semi-solid battery is simple. While significantly reducing the direct current internal resistance (DCIR), the preparation efficiency of the battery can be improved, and the application has good scalability.

[0016] The above-mentioned acrylic monomer refers to a compound in which the vinyl hydrogen in acrylic acid or acrylic acid is replaced by a hydrocarbon group, such as acrylic acid, methacrylic acid, 2-ethyl acrylic acid, 2-propyl acrylic acid, butenoic acid, 3,3-dimethyl acrylic acid, etc., but is not limited thereto.

[0017] The acrylate monomer refers to an ester monomer corresponding to the above-mentioned acrylic monomer, which can be a methyl ester, an ethyl ester, a propyl ester, a butyl ester, a 1,3-butylene glycol diacrylate, a pentaerythritol ester, etc., but is not limited thereto. In particular, when the above-mentioned first polymer monomer contains an acrylate monomer, the copolymer formed by the unsaturated monomer containing fluorine can further improve the stability of the electrode / electrolyte interface, reduce the direct current resistance, and thus improve the performance of the semi-solid titanium battery.

[0018] In some preferred embodiments of the present application, the first polymer monomer includes any one or more of acrylic acid, methacrylic acid, methyl methacrylate, butyl acrylate, 1,3-butylene glycol diacrylate, pentaerythritol tetraacrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, and pentaerythritol triacrylate, which are not only widely available, but also can better play a role in the semi-solid battery electrolyte precursor of the present application to reduce the DCIR of the battery.

[0019] In some typical embodiments of the present application, the first polymer monomer includes any one or more of methyl methacrylate, butyl acrylate, 1,3-butylene glycol diacrylate, pentaerythritol tetraacrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, and pentaerythritol triacrylate, which can further reduce the internal resistance of the battery and improve the cycle performance.

[0020] In some preferred embodiments of the present application, the second polymer monomer includes any one or more of 2,2,2-trifluoroethyl methacrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate, which facilitates polymerization with the first polymer monomer and the copolymer formed has a significant effect on improving the interface stability and reducing the direct current resistance, thereby further improving the performance of the battery.

[0021] The initiator is any compound that can initiate the polymerization of the first polymer monomer and the second polymer monomer, which can be selected in the related art, and the present application does not have a special requirement therefor. As an example, the initiator includes any one or more of, but is not limited to, azobisisobutyronitrile, azobisisoheptyl nitrile, benzoyl, dicumyl peroxide, dibenzoyl peroxide, potassium persulfate, and ammonium persulfate.

[0022] In order to better play the role of the first polymer monomer and the second polymer monomer in the semi-solid battery electrolyte precursor, in some embodiments of the present application, the mass ratio of the first polymer monomer to the second polymer monomer is 3:1-1:1, preferably 3:1-2:1.

[0023] In some embodiments of the present application, the mass of the initiator is 0.5-2 wt% of the total mass of the first polymer monomer and the second polymer monomer, and the use of the electrolyte precursor in the preparation of the battery makes the polymer monomers have a more appropriate polymerization rate, which is conducive to further improving the performance of the battery.

[0024] In the semi-solid electrolyte precursor of the present application, in addition to the first polymer monomer, the second polymer monomer and the initiator described above, conventional electrolyte components such as lithium salt and solvent can also be included.

[0025] The specific types of lithium salt or solvent can be selected in the related art, and the present application is not particularly limited. In some embodiments of the present application, the lithium salt includes any one or more of lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), lithium triflate (LiCF3SO3), lithium bis(trifluoromethylsulfonyl)imide (LiTFSI), lithium bis(fluorosulfonyl)imide (LiFSI), lithium difluoro(oxalato)borate (LiODFB), lithium perchlorate (LiClO4) and lithium bis(oxalato)borate (LiBOB). In some embodiments of the present application, the solvent includes any one or more of propylene carbonate (PC), ethylene carbonate (EC), methyl ethyl carbonate (EMC), dimethyl carbonate (DMC), diethyl carbonate (DEC), dimethyl ether (DME) and ethyl propionate (EP).

[0026] In some embodiments of the present application, in order to further improve the performance of the battery and improve the role of the copolymer formed by polymerization in stabilizing the interface, the mass of the first polymer monomer is 0.5-5 wt% of the total mass of the semi-solid battery electrolyte precursor, and the mass of the second polymer monomer is 0.5-2.5 wt% of the total mass of the semi-solid battery electrolyte precursor. Illustratively, the mass of the first polymer monomer is 0.5 wt%, 1 wt%, 1.2 wt%, 1.5 wt%, 1.8 wt%, 2 wt%, 2.2 wt%, 2.5 wt%, 2.8 wt%, 3 wt%, 3.2 wt%, 3.5 wt%, 3.8 wt%, 4 wt%, 4.2 wt%, 4.5 wt%, 4.7 wt% or 5 wt% of the total mass of the semi-solid battery electrolyte precursor. Illustratively, the mass of the second polymer monomer is 0.5 wt%, 0.7 wt%, 1 wt%, 1.2 wt%, 1.5 wt%, 1.8 wt%, 2 wt%, 2.2 wt% or 2.5 wt% of the total mass of the semi-solid battery electrolyte precursor.

[0027] In some preferred embodiments of the present application, the sum of the mass of the first polymer monomer and the second polymer monomer accounts for 1.5%-3% of the total mass of the semi-solid battery electrolyte precursor. For example, the sum of the mass of the first polymer monomer and the second polymer monomer accounts for 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, 2.6%, 2.7%, 2.8%, 2.9% or 3% of the total mass of the semi-solid battery electrolyte precursor.

[0028] In some typical embodiments of the present application, the mass of the first polymer monomer is 0.5-5 wt% of the total mass of the semi-solid battery electrolyte precursor, the mass of the second polymer monomer is 0.5-2.5 wt% of the total mass of the semi-solid battery electrolyte precursor, and the mass ratio of the first polymer monomer to the second polymer monomer is 3:1-1:1, preferably 3:1-2:1, and the mass of the initiator is 0.5-2 wt% of the total mass of the first polymer monomer and the second polymer monomer. The semi-solid battery electrolyte precursor can form an electrolyte containing a fluorine-containing copolymer with more excellent comprehensive performance, and the semi-solid battery containing the same has a more stable electrode / electrolyte interface and a lower DCIR.

[0029] The semi-solid battery electrolyte precursor described above can also contain an additive. The type and amount of the additive can be referred to related technologies, and those skilled in the art can add the additive to the electrolyte precursor of the present application according to the type and amount of the additive in the electrolyte in related technologies. Herein, the present application will not be described in detail.

[0030] According to another typical embodiment of the present application, a semi-solid battery electrolyte is provided, which is obtained by in-situ polymerization of any one of the semi-solid battery electrolyte precursors described above.

[0031] The semi-solid battery electrolyte precursor described above selects the first polymer monomer having an acrylic acid or acrylate structure and the second polymer monomer having an unsaturated structure containing fluorine, and the copolymer formed in the semi-solid battery electrolyte obtained by in-situ polymerization of the semi-solid battery electrolyte precursor can improve the stability of the electrode / electrolyte interface. Even if there is monomer residue, a SEI film with good stability can be formed in the subsequent film formation stage, and the electrode / electrolyte interface is optimized. At the same time, the semi-solid battery electrolyte precursor of the present application can be adapted to a variety of monomers, and different electrolyte systems can be designed according to the battery requirements. The subsequent preparation process for the semi-solid battery is simple, which can significantly reduce the direct current internal resistance (DCIR) while improving the preparation efficiency of the battery, and has good scalability and feasibility.

[0032] According to another typical embodiment of the present application, a preparation method of a semi-solid battery is provided, which comprises: injecting the semi-solid battery electrolyte precursor of any one of the above into an electric core for in-situ polymerization.

[0033] The preparation method enables in-situ polymerization of the first polymer monomer having an acrylic acid or acrylate structure and the second polymer monomer having a fluorine-containing unsaturated structure under the action of an initiator, and the formed copolymer can improve the stability of the electrode / electrolyte interface. Even if monomer residues exist, an SEI film with good stability can be formed in the subsequent film forming stage, the electrode / electrolyte interface is optimized, the direct current resistance of the battery can be significantly reduced, and the cycle performance of the battery is improved. In addition, compared with the secondary injection method and other methods, the method does not increase other process flow, reduces the time cost, improves the efficiency, and has good scalability feasibility.

[0034] In some embodiments of the present application, after the semi-solid battery electrolyte precursor is injected into the electric core, the temperature for in-situ polymerization is 50-70°C, the time for in-situ polymerization is 6-12h, and the formed electrolyte containing fluorine-containing copolymer has excellent performance.

[0035] In some preferred embodiments of the present application, before in-situ polymerization, the semi-solid battery electrolyte precursor is injected into the electric core, vacuum packaged, and left to stand for 24-50h to ensure that the electrolyte is fully soaked into the electrode. Preferably, standing is carried out at 15-35°C or at room temperature.

[0036] In some embodiments of the present application, the preparation method comprises: preparing a positive electrode sheet, a negative electrode sheet and a separator into a dry electric core. In the preparation method of the semi-solid battery of the present application, the types and preparation methods of the positive electrode sheet, the negative electrode sheet and the separator are not limited, and those skilled in the art can select them in the related art.

[0037] In some typical embodiments of the present application, the positive electrode material of the positive electrode sheet comprises any one or more of lithium cobaltate, ternary material, lithium iron phosphate, lithium-rich manganese-based material and spinel lithium manganate.

[0038] In some typical embodiments of the present application, the negative electrode material of the negative electrode sheet comprises any one or more of graphite, amorphous carbon, lithium titanate, SiOx / C composite material and Sn-based composite material.

[0039] In some typical embodiments of the present application, the preparation method of the semi-solid battery comprises: Step 1, preparation of electrolyte precursor: mixing lithium salt, solvent, additive, first polymer monomer, second polymer monomer and initiator; Step 2, preparation of battery cell: assembling the positive electrode sheet, negative electrode sheet and separator into a shell to prepare a dry battery cell; Step 3, liquid injection and packaging: injecting the prepared electrolyte into the dry battery cell, vacuum packaging, and standing at room temperature for 24-50 hours; Step 4, in-situ polymerization: the battery cell is placed in an oven at 50-70°C for 6-12 hours; Step 5, formation and capacity measurement: formation at 40-50°C and capacity measurement at room temperature, thereby preparing the semi-solid battery. Preferably, the formation temperature is 45°C.

[0040] According to another typical embodiment of the present application, a semi-solid battery is provided, which is prepared by any of the above-mentioned preparation methods of semi-solid battery or comprises the above-mentioned semi-solid battery electrolyte.

[0041] The semi-solid battery prepared by the above preparation method enables the in-situ polymerization of the first polymer monomer with acrylic acid or acrylate structure and the second polymer monomer with fluorine-containing unsaturated structure under the action of the initiator, and the semi-solid electrolyte containing the above copolymer can improve the stability of the electrode / electrolyte interface. Even if there is monomer residue, a SEI film with good stability can be formed in the subsequent film formation stage, the electrode / electrolyte interface is optimized, the direct current resistance of the battery can be significantly reduced, and the cycle performance of the battery is obviously improved.

[0042] The beneficial effects that can be achieved by the present application will be further illustrated below with examples and comparative examples.

[0043] Example 1

[0044] Preparation of electrolyte precursor:

[0045] 7.5 g of pentaerythritol tetraacrylate, 2.5 g of 2,2,2-trifluoroethyl methacrylate and 0.1 g of azobisisobutyronitrile were added to 490 g of electrolyte to prepare an electrolyte precursor;

[0046] The electrolyte is composed of lithium salt, organic solvent and additive. The lithium salt is 1M LiPF6, the organic solvent is obtained by mixing ethylene carbonate EC and methyl ethyl carbonate EMC at a volume ratio of 3:7, and the additive is 3wt% vinylene carbonate VC and 1wt% fluoroethylene carbonate FEC.

[0047] Preparation of square dry battery cell:

[0048] The positive electrode active material nickel cobalt manganese ternary material 96wt%, the conductive agent 2.8wt%, the binder 1.2wt% and the solvent are mixed and stirred uniformly to obtain a positive electrode slurry. Then the positive electrode slurry is uniformly coated on both sides of the positive electrode current collector, and after drying, rolling, slitting and other steps, a positive electrode sheet is prepared;

[0049] The negative electrode active material graphite 96wt%, the conductive agent 2wt%, the binder 2wt% and the solvent are mixed and stirred uniformly to obtain a negative electrode slurry. Then the negative electrode slurry is uniformly coated on both sides of the negative electrode current collector, and after drying, rolling and other steps, a negative electrode sheet is prepared;

[0050] The positive electrode sheet, the negative electrode sheet and the separator are assembled into a shell to prepare a square dry battery.

[0051] Liquid injection packaging: the prepared electrolyte precursor is injected into the square dry battery, vacuum packaged, and placed at room temperature for 48h.

[0052] In-situ polymerization: the battery is placed in an oven at 60℃ for 6h.

[0053] Formation and capacity: formation is carried out at 45℃, and capacity is carried out at room temperature to prepare a square semi-solid battery.

[0054] Example 2

[0055] The difference from example 1 is that in the preparation of the electrolyte precursor, the same mass of methyl methacrylate is used to replace pentaerythritol tetraacrylate.

[0056] Example 3

[0057] The difference from example 1 is that in the preparation of the electrolyte precursor, the same mass of methyl methacrylate is used to replace pentaerythritol tetraacrylate.

[0058] Example 4

[0059] The difference from example 1 is that in the preparation of the electrolyte precursor, the same mass of 2,2,3,3,3-pentafluoropropyl methacrylate is used to replace 2,2,2-trifluoroethyl methacrylate.

[0060] Example 5

[0061] The difference from example 1 is that in the preparation of the electrolyte precursor, the amount of 2,2,2-trifluoroethyl methacrylate added is 7.5g.

[0062] Example 6

[0063] The difference from example 1 is that in the preparation of the electrolyte precursor, the amount of 2,2,2-trifluoroethyl methacrylate added is 10g.

[0064] Example 7

[0065] The difference from Example 1 is that the amount of 2,2,2-trifluoroethyl methacrylate added in the preparation of electrolyte precursor is 1.5 g.

[0066] Example 8

[0067] The difference from Example 1 is that the amount of pentaerythritol tetraacrylate added in the preparation of electrolyte precursor is 2.5 g.

[0068] Example 9

[0069] The difference from Example 1 is that the amount of pentaerythritol tetraacrylate added in the preparation of electrolyte precursor is 25 g, the amount of 2,2,2-trifluoroethyl methacrylate added is 10 g, and the amount of initiator added is 0.7 g.

[0070] Example 10

[0071] The difference from Example 1 is that the cell is placed in an oven at 70°C for 5 h during in-situ polymerization.

[0072] Comparative Example 1

[0073] The difference from Example 1 is that 10 g of pentaerythritol tetraacrylate is added in the electrolyte in the preparation of electrolyte precursor, and no 2,2,2-trifluoroethyl methacrylate is added.

[0074] Comparative Example 2

[0075] The difference from Example 1 is that 10 g of 2,2,2-trifluoroethyl methacrylate is added in the electrolyte in the preparation of electrolyte precursor, and no pentaerythritol tetraacrylate is added.

[0076] Comparative Example 3

[0077] The difference from Example 1 is that the same mass of fluoroethylene carbonate is used to replace pentaerythritol tetraacrylate in the preparation of electrolyte precursor.

[0078] Comparative Example 4

[0079] The difference from Example 1 is that the same mass of vinyl ethylene carbonate is used to replace pentaerythritol tetraacrylate in the preparation of electrolyte precursor.

[0080] Comparative Example 5

[0081] The difference from Example 1 is that the same mass of N,N-dimethylacrylamide is used to replace pentaerythritol tetraacrylate in the preparation of electrolyte precursor.

[0082] The square semi-solid batteries prepared in the above examples and comparative examples were tested according to the following method, and the test results are listed in Table 1.

[0083] DC impedance DCIR: at 50% SOC, the battery was tested at 1C rate under constant current I charge-discharge, the charge-discharge time was 10s, and the time recording condition was 1s. The change of voltage ΔU in the charging or discharging process was recorded, and DCIR = ΔU / I.

[0084] Electrochemical performance: under room temperature conditions, 1C constant current constant voltage charging to 4.2V, 0.05C cutoff, standing for 10min, 1C constant current discharging to 2.75V, standing for 10min, and cycling for 600 cycles to obtain the capacity retention rate.

[0085] Table 1

[0086] DC impedance / ΩCapacity retention rate / %Example 1 41.39 8.45 Example 2 50.69 6.98 Example 3 53.79 6.53 Example 4 48.99 7.09 Example 5 43.89 7.86 Example 6 46.39 7.52 Example 7 44.39 7.65 Example 8 47.99 7.22 Example 9 56.39 5.93 Example 10 42.19 8.21 Comparative example 1 52.89 6.76 Comparative example 2 55.49 6.21 Comparative example 3 59.79 5.14 Comparative example 4 58.39 5.76 Comparative example 5 60.99 4.79

[0087] From the above description, it can be seen that the above-mentioned examples of the application achieve the following technical effects: the above-mentioned semi-solid battery electrolyte precursor selects the above-mentioned first polymer monomer with acrylic acid or acrylate structure and the second polymer monomer with unsaturated structure containing fluorine, and the copolymer formed can improve the stability of the electrode / electrolyte interface. Even if there is monomer residue, an SEI film with good stability can be formed in the subsequent film forming stage, and the electrode / electrolyte interface is optimized. At the same time, the monomer types of the semi-solid battery electrolyte precursor of the application are more suitable, which can design different electrolyte systems according to the battery demand, and the subsequent preparation process for semi-solid battery is simple. At the same time, it can significantly reduce the direct current resistance (DCIR), improve the preparation efficiency of the battery, and has good scalability feasibility.

Claims

1. A semi-solid battery electrolyte precursor, comprising: a first polymer monomer, a second polymer monomer, and an initiator; the first polymer monomer is an acrylic monomer or an acrylate monomer; the second polymer monomer is a fluorine-containing unsaturated monomer.

2. The semi-solid battery electrolyte precursor of claim 1, wherein, the first polymer monomer includes any one or more of acrylic acid, methacrylic acid, methyl methacrylate, butyl acrylate, 1,3-butanediol diacrylate, pentaerythritol tetraacrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, and pentaerythritol triacrylate.

3. The semi-solid battery electrolyte precursor of claim 2, wherein, the first polymer monomer includes any one or more of methyl methacrylate, butyl acrylate, 1,3-butanediol diacrylate, pentaerythritol tetraacrylate, ethoxylated trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, and pentaerythritol triacrylate.

4. The semi-solid battery electrolyte precursor of claim 2, wherein, the second polymer monomer includes any one or more of 2,2,2-trifluoroethyl methacrylate, 2,2,3,3-tetrafluoropropyl methacrylate, 2,2,3,3,3-pentafluoropropyl methacrylate, and 1,1,1,3,3,3-hexafluoroisopropyl methacrylate.

5. The semi-solid battery electrolyte precursor of claim 4, wherein, the initiator includes any one or more of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl, dicumyl peroxide, dibenzoyl peroxide, potassium persulfate, and ammonium persulfate.

6. The semi-solid battery electrolyte precursor of any one of claims 1 to 5, wherein, a mass ratio of the first polymer monomer to the second polymer monomer is 3:1-1:

1.

7. The semi-solid battery electrolyte precursor of claim 6, wherein, a mass ratio of the first polymer monomer to the second polymer monomer is 3:1-2:

1.

8. The semi-solid battery electrolyte precursor of claim 7, wherein, a mass of the initiator is 0.5-2 wt% of a total mass of the first polymer monomer and the second polymer monomer.

9. The semi-solid battery electrolyte precursor of any one of claims 1 to 5, wherein, the semi-solid battery electrolyte precursor further includes a lithium salt and a solvent.

10. The semi-solid battery electrolyte precursor of claim 9, wherein, the lithium salt includes any one or more of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium triflate, lithium bistrifluoromethylsulfonylimide, lithium bisfluorosulfonylimide, lithium difluoro(oxalato)borate, lithium perchlorate, and lithium bis(oxalato)borate.

11. The semi-solid battery electrolyte precursor of claim 10, wherein, the solvent includes any one or more of propylene carbonate, ethylene carbonate, methyl ethyl carbonate, dimethyl carbonate, diethyl carbonate, dimethyl ether, and ethyl propionate.

12. The semi-solid battery electrolyte precursor of claim 9, wherein, a mass of the first polymer monomer is 0.5-5 wt% of a total mass of the semi-solid battery electrolyte precursor, and a mass of the second polymer monomer is 0.5-2.5 wt% of the total mass of the semi-solid battery electrolyte precursor.

13. The semi-solid battery electrolyte precursor of claim 12, wherein, a sum of masses of the first polymer monomer and the second polymer monomer is 1.5%-3% of a total mass of the semi-solid battery electrolyte precursor.

14. The semi-solid battery electrolyte precursor of claim 1, wherein, the semi-solid battery electrolyte precursor further includes an additive.

15. A semi-solid battery electrolyte obtained by in-situ polymerization of the semi-solid battery electrolyte precursor of any one of claims 1-14.

16. A method of making a semi-solid battery, comprising: injecting the semi-solid battery electrolyte precursor of any one of claims 1-14 into an electric cell for in-situ polymerization.

17. The method of producing a semi-solid battery according to claim 16, wherein a temperature of the in-situ polymerization is 50-70°C, and a time of the in-situ polymerization is 6-12 h.

18. The method of producing a semi-solid battery according to claim 17, wherein Before the in-situ polymerization, the semi-solid battery electrolyte precursor is injected into the battery cell, vacuum packaged, and left to stand for 24-50 hours.

19. The method of producing a semi-solid battery of claim 16, wherein, The method comprises the following steps: The positive electrode sheet, the negative electrode sheet, and the separator are prepared into a dry battery cell. Preferably, the positive electrode material of the positive electrode sheet comprises any one or more of lithium cobaltate, ternary material, lithium iron phosphate, lithium-rich manganese-based material, and spinel lithium manganate. Preferably, the negative electrode material of the negative electrode sheet comprises any one or more of graphite, amorphous carbon, lithium titanate, SiOx / C composite material, and Sn-based composite material.

20. A semi-solid battery prepared by the method for preparing a semi-solid battery according to any one of claims 16 to 19 or comprising the semi-solid battery electrolyte according to claim 15.