Electrolyte membrane, method for preparing electrolyte membrane, semi-solid state battery, and electrical apparatus

Abstract

In order to solve the problems in existing semi-solid state batteries of poor safety and inadequate charging and discharging performance caused by poor mechanical strength of electrolyte membranes, an electrolyte membrane, a method for preparing the electrolyte membrane, a semi-solid state battery, and an electrical apparatus are provided. The electrolyte membrane comprises a polymer electrolyte base membrane and an inorganic solid electrolyte, the polymer electrolyte base membrane being a porous thin film, and the inorganic solid electrolyte being distributed in the polymer electrolyte base membrane in the form of granules.

Description

An electrolyte membrane and its preparation method, a semi-solid battery and an electrical device thereof

[0001] This application claims priority to Chinese Patent Application No. 202510019164.7, filed on January 6, 2025, entitled "An Electrolyte Membrane and its Preparation Method, a Semi-Solid Battery and an Electrical Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application belongs to the field of battery technology, specifically relating to an electrolyte membrane and its preparation method, a semi-solid battery, and an electrical device. Background Technology

[0003] Semi-solid-state batteries combine the advantages of solid-state and liquid batteries, employing a combination of partially liquid and solid electrolytes to improve ionic conductivity and interfacial stability. Due to their superior performance in energy density, safety, and cycle life, semi-solid-state batteries are widely used in electric vehicles, energy storage systems, and consumer electronics. Solid electrolytes are the key factor in achieving these performance characteristics in semi-solid-state batteries.

[0004] Solid electrolytes can be mainly classified into three categories based on their materials: sulfides, oxides, and organic polymers. Oxide electrolytes such as lithium lanthanum zirconium oxide (LLZO) and lithium titanium aluminum phosphate (LATP), as well as sulfide electrolytes such as LPSC, are currently the most widely studied solid electrolytes. However, when these solid electrolytes are fabricated into porous electrolyte membranes, their poor mechanical strength leads to issues with battery safety and charge / discharge performance. Furthermore, the existing fabrication processes for porous electrolyte membranes are complex, and process stability is difficult to control. Summary of the Invention

[0005] To address the problem of poor safety and charge / discharge performance in existing semi-solid batteries due to the poor mechanical strength of the electrolyte membrane, this application provides an electrolyte membrane, its preparation method, a semi-solid battery, and an electrical device.

[0006] The technical solution adopted in this application to solve the above-mentioned technical problems is as follows:

[0007] In a first aspect, this application provides an electrolyte membrane comprising a polymer electrolyte substrate membrane and an inorganic solid electrolyte, wherein the polymer electrolyte substrate membrane is a porous thin film comprising a polymer and a lithium salt; and the inorganic solid electrolyte is distributed in particulate form within the polymer electrolyte substrate membrane.

[0008] Optionally, the inorganic solid electrolyte is selected from halide solid electrolytes.

[0009] Optionally, the mass of the halide solid electrolyte is 0.1% to 10% of the mass of the polymer electrolyte substrate membrane.

[0010] Optionally, the halide solid electrolyte is selected from Li a (M b )X c X' d Wherein, M is selected from one or more of Ga, Y, In, Mg, Sr, Sc, Sn, Pb, Ti, Zr, Hf, Nb, Ta, W, Fe, Ru, Al, and lanthanide metals; X is selected from one or more of halogens; X' is selected from one or more of halide ions, N ions, oxygen-containing anion groups, and pseudohalide anions; 0.5≤a≤5, 0.2≤b≤4, c+d=a+bε, where ε is the weighted average valence of element M.

[0011] Optionally, the oxygen-containing anionic group is selected from O 2- S 2- CN - CO3 2- PO4 3- P2O7 4- SO4 2- One or more of the following; the pseudohalide anion is selected from SCN. - PF6 - NH2 - AlF4 - or BF4 - One or more of them.

[0012] Optionally, the halide solid electrolyte is selected from Li₂MnCl₄, Li₂ZnCl₄, Li₂ZrOCl₄, LiYbF₄, LiAlF₄, Li₃YCl₆, Li₃InCl₆, and Li₃InCl₄. 5.5 F 0.5 Li3TaCl6, Li 0.388 Ta 0.238 La 0.475 One or more of Cl3 and Li6CoCl8.

[0013] Optionally, the particle size of the inorganic solid electrolyte is 5 nm to 3 μm.

[0014] Optionally, at least one of the following conditions must be met:

[0015] The permeability of the electrolyte membrane is 50–2000 s / 100cc·in. 2 1.22 kPa;

[0016] The pore size of the electrolyte membrane is 100 nm to 50 μm;

[0017] The porosity of the electrolyte membrane is 5% to 70%.

[0018] Optionally, the molar ratio of the polymer to the lithium salt is (5:1) to (20:1).

[0019] Optionally, the polymer is selected from at least one of polyethylene oxide, polyacrylate, polyvinylidene fluoride, polyvinylidene fluoride hexafluoropropylene copolymer, polysiloxane, polyethylene glycol, sodium polystyrene sulfonate, polysulfone, polyethersulfone, polypropylene carbonate, polymethyl methacrylate, polyacrylonitrile, and polyimide.

[0020] And / or, the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloyl)borate, and lithium difluorooxaloylborate.

[0021] Optionally, the thickness of the electrolyte membrane is 5 μm to 300 μm.

[0022] Secondly, this application provides a method for preparing the electrolyte membrane as described above, comprising the following steps:

[0023] The polymer and the lithium salt are dispersed in a mixed solvent, then an inorganic solid electrolyte is added, and after mixing, the mixture is cast onto a substrate. After drying to remove the mixed solvent, an electrolyte membrane is obtained.

[0024] The mixed solvent includes a first solvent that is miscible with the polymer and a second solvent that is insoluble with the polymer.

[0025] Optionally, the mass of the mixed solvent is 3 to 15 times the mass of the polymer, and the mass ratio of the first solvent to the second solvent is 1:10 to 10:1.

[0026] Optionally, the first solvent is selected from one or more of acetonitrile, acetone, ethyl acetate, butanone, diethyl ether, hexane, n-heptane, chloroform, tetrahydrofuran, N,N-dimethylacetamide, N,N-dimethylacetamide, 2,2,2-trifluoro-N,N-dimethylformamide, and N-methylpyrrolidone.

[0027] The second solvent is selected from one or more of butyl butyrate, ethyl butyrate, isobutyl isobutyrate, ethanol, and butanol.

[0028] Optionally, the drying temperature is 60–160°C, the drying time is 6–24 h, and the relative vacuum degree during drying is -0.1–0 MPa.

[0029] Thirdly, this application provides a method for preparing the electrolyte membrane as described above, comprising the following steps:

[0030] The polymer, lithium salt, plasticizer, and inorganic solid electrolyte are mixed evenly to obtain a mixture.

[0031] The mixture is hot-pressed to obtain a film preform;

[0032] The plasticizer is extracted from the membrane preform using a third solvent to obtain an electrolyte membrane.

[0033] Optionally, the hot pressing temperature is 100–400°C and the pressure is 10–300 MPa.

[0034] Optionally, the plasticizer is selected from one or more of ethylene carbonate, ethyl methyl carbonate, diethyl carbonate, propylene carbonate, N,N-dimethylacetamide, N,N-dimethylacetamide, 2,2,2-trifluoro-N,N-dimethylformamide, and dibutyl phthalate.

[0035] And / or, the third solvent is selected from one or more of acetonitrile, acetone, ethyl acetate, diethyl ether, hexane, chloroform, tetrahydrofuran, and N-methylpyrrolidone.

[0036] Optionally, the plasticizer accounts for 5% to 40% of the polymer by mass.

[0037] Fourthly, this application provides a semi-solid-state battery, comprising a positive electrode, a negative electrode electrolyte, and an electrolyte membrane as described in any one of the above; or, comprising an electrolyte and an electrolyte membrane prepared by the preparation method of the electrolyte membrane as described in any one of the above; wherein the electrolyte membrane is located between the positive electrode and the negative electrode.

[0038] Optionally, the electrolyte includes a fourth solvent, a lithium salt, a first additive, and a second additive;

[0039] The fourth solvent is selected from at least one of ethylene carbonate, propylene carbonate, butene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, dimethyl sulfite, diethyl sulfite, dipropyl sulfite, ethylene sulfite, methyl acetate, ethyl formate, ethyl propionate, methyl propionate, ethylene glycol n-butyl ether, methyl butyl ether, methyl tert-butyl ether, dibutyl ether, ethylene glycol dimethyl ether, 1,3-dioxolane, tetraethylene glycol dimethyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether.

[0040] The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(fluorosulfonyl)borate, and lithium difluorooxalate borate.

[0041] The first additive is selected from at least one of the following: tripropynyl phosphate, 4-nitrobenzene trifluoroacetic acid, fluoroethers such as 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, 1,3-propanesulfonyl lactone, vinyl sulfate, toluene, 1,2-xylene, 1,3-xylene, 1,4-xylene, fluorobenzene, 1,2-difluorobenzene, 1,3-difluorobenzene, 1,4-difluorobenzene, 1,2,4-trifluorobenzene, 1,3,5-trifluorobenzene, 1,2,3,4-tetrafluorobenzene, 1,2,3,5-tetrafluorobenzene, 1,2,4,5-tetrafluorobenzene, pentafluorobenzene, and hexafluorobenzene;

[0042] The second additive is selected from at least one of vinylene carbonate, fluoroethylene carbonate, and LiNO3.

[0043] Optionally, the volume ratio of the fourth solvent to the first additive is (1:10) to (10:1);

[0044] And / or, the mass content of the second additive in the electrolyte is 0.1% to 10%.

[0045] Optionally, the electrolyte comprises an ester-based organic solvent and a lithium salt, wherein the ester-based organic solvent is selected from at least one of ethylene carbonate, propylene carbonate, butene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, dimethyl sulfite, diethyl sulfite, dipropyl sulfite, ethylene sulfite, methyl acetate, ethyl acetate, ethyl formate, ethyl propionate, and methyl propionate.

[0046] The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloacetate borate), and lithium difluorooxaloacetate borate.

[0047] Optionally, the electrolyte comprises an ether-based organic solvent and a lithium salt, wherein the ether-based organic solvent is selected from at least one of ethylene glycol n-butyl ether, methyl butyl ether, methyl tert-butyl ether, dibutyl ether, ethylene glycol dimethyl ether, 1,3-dioxolane, tetraethylene glycol dimethyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether;

[0048] The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloacetate borate), and lithium difluorooxaloacetate borate.

[0049] Optionally, the electrolyte includes an ionic liquid and a lithium salt, wherein the ionic liquid is selected from one or more of imidazole ionic liquids, pyridine ionic liquids, quaternary ammonium ionic liquids, quaternary phosphorus ionic liquids, pyrrolidine ionic liquids, and piperidine ionic liquids;

[0050] The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloyl)borate, and lithium difluorooxaloylborate.

[0051] Optionally, the concentration of the lithium salt in the electrolyte is 0.5 mol / L to 5 mol / L.

[0052] Optionally, the positive electrode includes a positive electrode active material, which is selected from one or more of lithium nickel cobalt manganese oxide, NCA, NCMA, lithium iron manganese phosphate, lithium iron phosphate, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium lithium manganese-based oxide, lithium nickel manganese oxide, and lithium vanadium oxide phosphate.

[0053] The negative electrode includes a negative electrode active material, which is selected from one or more of graphite, LTO, Si, silicon suboxide, silicon dioxide, Si-C, lithium metal, lithium alloy, Sn, Sn-C, SnO, and tin alloy.

[0054] Fifthly, this application provides an electrical device including a semi-solid battery as described in any of the above claims.

[0055] In this application, firstly, the inorganic solid electrolyte is uniformly distributed in particulate form within the polymer electrolyte substrate membrane, significantly improving the ionic conductivity of the electrolyte membrane. The inorganic solid electrolyte forms highly efficient ion conduction channels within the polymer electrolyte substrate membrane, ensuring efficient movement of lithium ions within the battery, thereby enhancing the battery's charge-discharge performance. The polymer electrolyte substrate membrane is a porous membrane; its pores not only contribute to improving the ionic conductivity of the electrolyte but also allow for compatibility with various electrolytes, making it adaptable to different electrolytes. Simultaneously, the pores of the polymer electrolyte substrate membrane provide a larger interfacial contact area, further improving ion conduction efficiency and the overall performance of the battery. The polymer electrolyte substrate membrane provides the necessary flexibility and mechanical strength for the electrolyte membrane, enabling it to adapt to deformation and stress changes within the battery and preventing mechanical damage during use. The addition of the inorganic solid electrolyte further enhances the mechanical properties of the electrolyte membrane, ensuring that the electrolyte membrane maintains its structural integrity during multiple charge-discharge cycles.

[0056] The electrolyte membrane preparation method in the second aspect achieves precise control of the pore size and pore distribution of the electrolyte membrane by controlling the solubility relationship between the first and second solvents in the mixed solvent and the polymer, as well as the drying temperature and time, through phase separation. The electrolyte membrane preparation methods in the second and third aspects simplify the electrolyte membrane preparation process, improve the stability and controllability of the process, solve the problems of complex and unstable existing electrolyte membrane processes, and reduce production costs. Detailed Implementation

[0057] To make the technical problems, technical solutions, and beneficial effects solved by this application clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0058] One embodiment of this application provides an electrolyte membrane, comprising a polymer electrolyte base membrane and an inorganic solid electrolyte. The polymer electrolyte base membrane is a porous film, comprising a polymer and a lithium salt. The inorganic solid electrolyte is distributed in particulate form within the polymer electrolyte base membrane.

[0059] In this application, the inorganic solid electrolyte is uniformly distributed in particulate form within the polymer electrolyte substrate membrane, significantly improving the ionic conductivity of the electrolyte membrane. The inorganic solid electrolyte forms highly efficient ion conduction channels within the polymer electrolyte substrate membrane, ensuring efficient movement of lithium ions within the battery, thereby enhancing the battery's charge-discharge performance. The polymer electrolyte substrate membrane is a porous membrane; its pores not only contribute to improving the ionic conductivity of the electrolyte but also allow for compatibility with various electrolytes, making it adaptable to different electrolytes. Simultaneously, the pores of the polymer electrolyte substrate membrane provide a larger interfacial contact area, further improving ion conduction efficiency and the overall battery performance. The polymer electrolyte substrate membrane provides the necessary flexibility and mechanical strength for the electrolyte membrane, enabling it to adapt to deformation and stress changes within the battery and preventing mechanical damage during use. The addition of the inorganic solid electrolyte further enhances the mechanical properties of the electrolyte membrane, ensuring that the electrolyte membrane maintains its structural integrity during multiple charge-discharge cycles.

[0060] In one embodiment, the inorganic solid electrolyte is selected from halide solid electrolytes. By selecting halide solid electrolytes, the introduction of sulfides is avoided, thereby further preventing the generation of toxic H2S gas in the electrolyte membrane, improving the environmental friendliness and safety of the electrolyte, and meeting more stringent environmental and safety standards.

[0061] In one embodiment, the mass of the halide solid electrolyte is 0.1% to 10% of the mass of the polymer electrolyte substrate membrane. By controlling the content of the halide solid electrolyte in the polymer electrolyte substrate membrane, the ionic conductivity and mechanical strength of the formed electrolyte membrane can be adjusted, thereby further enhancing the overall mechanical properties of the electrolyte membrane and ensuring that the electrolyte membrane maintains its structural integrity during multiple charge-discharge cycles.

[0062] Specifically, the mass of the halide solid electrolyte is 0.1%, 0.3%, 0.5%, 0.7%, 0.9%, 1.1%, 1.3%, 1.5%, 1.7%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, 5.5%, 6%, 6.5%, 7%, 7.5%, 8%, 8.5%, 9%, 9.5%, or 10% of the mass of the polymer electrolyte substrate membrane.

[0063] In a preferred embodiment, the mass of the halide solid electrolyte is 0.5% to 5% of the mass of the polymer electrolyte substrate membrane. Within this range, the ionic conductivity and mechanical strength of the electrolyte membrane can be further improved.

[0064] In one embodiment, the halide solid electrolyte is selected from Li a (M b )X c X' dWherein, M is selected from one or more of Ga, Y, In, Mg, Sr, Sc, Sn, Pb, Ti, Zr, Hf, Nb, Ta, W, Fe, Ru, Al, and lanthanide elements. X is selected from one or more halogens. X' is selected from one or more of halide ions, N ions, oxygen-containing anion groups, and pseudohalo anions. 0.5≤a≤5, 0.2≤b≤4, c+d=a+bε, where ε is the weighted average valence of element M. By selecting the above-mentioned halide solid electrolyte, ion conduction channels can be better formed in the electrolyte membrane, improving the ionic conductivity of the electrolyte membrane and further enhancing the charge and discharge performance of the battery.

[0065] In one embodiment, the oxygen-containing anionic group is selected from O 2- S 2- CN - CO3 2- PO4 3- P2O7 4- SO4 2- One or more of the following. The pseudohalo anion is selected from SCN. - PF6 - NH2 - AlF4 - or BF4 - One or more of them.

[0066] In a preferred embodiment, the halide solid electrolyte is selected from Li₂MnCl₄, Li₂ZnCl₄, Li₂ZrOCl₄, LiYbF₄, LiAlF₄, Li₃YCl₆, Li₃InCl₆, and Li₃InCl₄. 5.5 F 0.5 Li3TaCl6, Li 0.388 Ta 0.238 La 0.475 One or more of Cl3 and Li6CoCl8.

[0067] In one embodiment, the inorganic solid electrolyte has a particle size of 5 nm to 3 μm. By selecting an inorganic solid electrolyte within this particle size range, the inorganic solid electrolyte is uniformly distributed in the polymer electrolyte substrate membrane, forming efficient ion conduction channels. This ensures that lithium ions can move efficiently within the battery, thereby improving the battery's charge and discharge performance. Furthermore, selecting an inorganic solid electrolyte within this particle size range facilitates the control of its distribution in the polymer electrolyte substrate membrane. Inorganic solid electrolyte particles that are too small or too large will affect their uniformity in the polymer electrolyte substrate membrane, thus affecting the mechanical properties of the electrolyte membrane.

[0068] In a preferred embodiment, the particle size of the inorganic solid electrolyte is 50 nm to 300 nm.

[0069] In one embodiment, at least one of the following conditions is satisfied:

[0070] The permeability of the electrolyte membrane is 50–2000 s / 100cc·in. 2 • 1.22 kPa. The pore size of the electrolyte membrane is 100 nm to 50 μm.

[0071] The porosity of the electrolyte membrane is 5% to 70%.

[0072] By limiting the permeability, pore size, or porosity of the electrolyte membrane, a larger interfacial contact area is provided between the electrolyte and the electrolyte membrane, so that its porous structure can further improve the ionic conductivity of the electrolyte and facilitate its compounding with different electrolytes, thereby improving the overall performance of the battery.

[0073] In one embodiment, the molar ratio of the polymer to the lithium salt is (5:1) to (20:1). Specifically, the molar ratio of the polymer to the lithium salt includes, but is not limited to, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 11:1, 12:1, 13:1, 12:1, 15:1, 16:1, 17:1, 18:1, 19:1, or 20:1. By limiting the molar ratio of the polymer to the lithium salt, the flexibility of the polymer electrolyte substrate membrane is adjusted, allowing the electrolyte membrane to adapt to deformation and stress changes inside the battery, preventing mechanical damage to the electrolyte membrane during use.

[0074] In one embodiment, the polymer is selected from at least one of polyethylene oxide, polyacrylate, polyvinylidene fluoride, polyvinylidene fluoride hexafluoropropylene copolymer, polysiloxane, polyethylene glycol, sodium polystyrene sulfonate, polysulfone, polyethersulfone, polypropylene carbonate, polymethyl methacrylate, polyacrylonitrile, and polyimide. Selecting the above polymers facilitates the adjustment of the flexibility and mechanical strength of the polymer electrolyte base membrane.

[0075] And / or, the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloyl)borate, and lithium difluorooxaloylborate.

[0076] In one embodiment, the thickness of the electrolyte membrane is 5 μm to 300 μm. It should be noted that the thickness of the electrolyte membrane can be adjusted according to the needs of the battery and is not limited to 5 μm to 300 μm.

[0077] Secondly, one embodiment of this application also provides a method for preparing the electrolyte membrane as described above, comprising the following steps:

[0078] The polymer and the lithium salt are dispersed in a mixed solvent, then an inorganic solid electrolyte is added, and the mixture is cast onto a substrate. After drying to remove the mixed solvent, an electrolyte membrane is obtained.

[0079] The mixed solvent includes a first solvent that is miscible with the polymer and a second solvent that is insoluble with the polymer.

[0080] By selecting two solvents with different solubilities than the polymer as a mixed solvent, the interfacial tension and forces of the mixed solvent cause phase separation between the polymer and the inorganic solid electrolyte during casting, forming numerous tiny droplets or particles arranged in a porous structure. During drying, the droplets or particles fuse to form a stable porous film structure. This phase separation method achieves precise control of the pore size and pore distribution of the electrolyte membrane, simplifies the preparation process, improves process stability and controllability, solves the problems of complex and unstable existing electrolyte membrane processes, and reduces production costs.

[0081] In one embodiment, the mass of the mixed solvent is 3 to 15 times the mass of the polymer, and the mass ratio of the first solvent to the second solvent is 1:10 to 10:1. When the mass ratio of the first solvent to the second solvent is within this range, the pore size and porosity formed by the electrolyte membrane are uniform. If the content of the first solvent or the second solvent is too high, the pore size of the electrolyte membrane will vary greatly, affecting the mechanical strength of the electrolyte membrane.

[0082] In one embodiment, the first solvent is selected from one or more of acetonitrile, acetone, ethyl acetate, butanone, diethyl ether, hexane, n-heptane, chloroform, tetrahydrofuran, N,N-dimethylacetamide, N,N-dimethylacetamide, 2,2,2-trifluoro-N,N-dimethylformamide, and N-methylpyrrolidone.

[0083] The second solvent is selected from one or more of butyl butyrate, ethyl butyrate, isobutyl isobutyrate, ethanol, and butanol.

[0084] In one embodiment, the drying temperature is 60–160°C, the drying time is 6–24 hours, and the relative vacuum during drying is -0.1–0 MPa. By controlling the drying temperature and drying time, precise control of the pore size and pore distribution of the electrolyte membrane is achieved.

[0085] Thirdly, one embodiment of this application also provides a method for preparing the electrolyte membrane as described above, comprising the following steps:

[0086] The polymer, lithium salt, plasticizer, and inorganic solid electrolyte are mixed evenly to obtain a mixture.

[0087] The mixture is hot-pressed to obtain a preform.

[0088] The plasticizer is extracted from the membrane preform using a third solvent to obtain an electrolyte membrane.

[0089] Electrolyte membranes are prepared by hot pressing and extraction. The pore size and pore distribution of the membrane can be adjusted by controlling the content of plasticizer, which simplifies the preparation process of electrolyte membranes, improves the stability and controllability of the process, solves the problems of complex and unstable existing electrolyte membrane processes, and reduces production costs.

[0090] In one embodiment, the hot pressing temperature is 100–400°C and the pressure is 10–300 MPa.

[0091] In one embodiment, the plasticizer is selected from one or more of ethylene carbonate, methyl ethyl carbonate, diethyl carbonate, propylene carbonate, N,N-dimethylacetamide, N,N-dimethylacetamide, 2,2,2-trifluoro-N,N-dimethylformamide, and dibutyl phthalate.

[0092] And / or, the third solvent is selected from one or more of acetonitrile, acetone, ethyl acetate, diethyl ether, hexane, chloroform, tetrahydrofuran, and N-methylpyrrolidone. By using the aforementioned third solvent to extract the plasticizer, the dissolution of the polymer in the electrolyte membrane is avoided, thus preventing a reduction in the flexibility of the electrolyte membrane.

[0093] In one embodiment, the plasticizer accounts for 5% to 40% of the polymer mass. The pore size and porosity of the electrolyte membrane are adjusted by regulating the plasticizer content.

[0094] Fourthly, one embodiment of this application also provides a semi-solid-state battery, comprising a positive electrode, a negative electrode electrolyte, and an electrolyte membrane as described in any one of the above. Alternatively, it comprises an electrolyte and an electrolyte membrane prepared by the method described in any one of the above. The electrolyte membrane is located between the positive electrode and the negative electrode.

[0095] In one embodiment, the electrolyte includes a fourth solvent, a lithium salt, a first additive, and a second additive.

[0096] The fourth solvent is selected from at least one of ethylene carbonate, propylene carbonate, butene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, dimethyl sulfite, diethyl sulfite, dipropyl sulfite, ethylene sulfite, methyl acetate, ethyl formate, ethyl propionate, methyl propionate, ethylene glycol n-butyl ether, methyl butyl ether, methyl tert-butyl ether, dibutyl ether, ethylene glycol dimethyl ether, 1,3-dioxolane, tetraethylene glycol dimethyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether.

[0097] The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloyl)borate, and lithium difluorooxaloylborate.

[0098] The first additive is selected from at least one of tripropynyl phosphate, 4-nitrobenzene trifluoroacetic acid, fluoroethers such as 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, 1,3-propanesulfonyl lactone, vinyl sulfate, toluene, 1,2-xylene, 1,3-xylene, 1,4-xylene, fluorobenzene, 1,2-difluorobenzene, 1,3-difluorobenzene, 1,4-difluorobenzene, 1,2,4-trifluorobenzene, 1,3,5-trifluorobenzene, 1,2,3,4-tetrafluorobenzene, 1,2,3,5-tetrafluorobenzene, 1,2,4,5-tetrafluorobenzene, pentafluorobenzene, and hexafluorobenzene.

[0099] The second additive is selected from at least one of vinylene carbonate, fluoroethylene carbonate, and LiNO3.

[0100] By using the aforementioned first additive in conjunction with the electrolyte membrane, the stability of the electrolyte and electrolyte solution is improved, thereby further enhancing the cycle life of the battery.

[0101] In one embodiment, the volume ratio of the fourth solvent to the first additive is (1:10) to (10:1).

[0102] And / or, the mass content of the second additive in the electrolyte is 0.1% to 10%. By adjusting the content of the first and second additives, the stability of the electrolyte and electrolyte solution is further improved, thereby increasing the cycle life of the battery.

[0103] In one embodiment, the electrolyte comprises an ester-based organic solvent and a lithium salt, wherein the ester-based organic solvent is selected from at least one of ethylene carbonate, propylene carbonate, butene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, dimethyl sulfite, diethyl sulfite, dipropyl sulfite, ethylene sulfite, methyl acetate, ethyl acetate, ethyl formate, ethyl propionate, and methyl propionate.

[0104] The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloacetate borate), and lithium difluorooxaloacetate borate.

[0105] In one embodiment, the electrolyte comprises an ether-based organic solvent and a lithium salt, wherein the ether-based organic solvent is selected from at least one of ethylene glycol n-butyl ether, methyl butyl ether, methyl tert-butyl ether, dibutyl ether, ethylene glycol dimethyl ether, 1,3-dioxolane, tetraethylene glycol dimethyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether.

[0106] The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloacetate borate), and lithium difluorooxaloacetate borate.

[0107] In one embodiment, the electrolyte comprises an ionic liquid and a lithium salt, wherein the ionic liquid is selected from one or more of imidazole ionic liquids, pyridine ionic liquids, quaternary ammonium ionic liquids, quaternary phosphorus ionic liquids, pyrrolidine ionic liquids, and piperidine ionic liquids.

[0108] The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloyl)borate, and lithium difluorooxaloylborate.

[0109] In one embodiment, the imidazole ionic liquid includes one or more of 1-alkylimidazolium, 1-alkyl-3-methylimidazolium, and 1-alkyl-2,3-dimethylimidazolium, wherein the alkyl group is selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, or octadecyl; and the anion is selected from chlorine, bromine, iodine, tetrafluoroboric acid, hexafluorophosphate, acetic acid, bis(trifluoromethanesulfonyl)imide, nitric acid, perchloric acid, hydrogen sulfate, dihydrogen phosphate, trifluoromethanesulfonic acid, trifluoroacetic acid, and p-toluenesulfonic acid.

[0110] Preferably, the imidazole ionic liquid is selected from one or more of 1-methylimidazolium chloride, 1-methylimidazolium tetrafluoroborate, N-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium tetrafluoroborate, and 1-octyl-3-methylimidazolium hexafluorophosphate.

[0111] In one embodiment, the pyridine-based ionic liquid cation includes N-alkylpyridine, wherein the alkyl group is selected from ethyl, butyl, hexyl, or octyl; and the anion is selected from chlorine, bromine, tetrafluoroboric acid, hexafluorophosphate, or bis(trifluoromethanesulfonyl)imide.

[0112] Preferably, the pyridine ionic liquid is selected from one of N-ethylpyridine chloride, N-ethylpyridine tetrafluoroborate, and N-ethylpyridine bis(trifluoromethanesulfonyl)imide.

[0113] In one embodiment, the quaternary ammonium ionic liquid cation includes tetraethylammonium, tetrabutylammonium, alkyltriethylammonium, and alkyltributylammonium, wherein the alkyl group is selected from ethyl, butyl, hexyl, or octyl; the anion includes chlorine, bromine, tetrafluoroboric acid, hexafluorophosphate, or bis(trifluoromethanesulfonyl)imide.

[0114] Preferably, the quaternary ammonium ionic liquid is selected from one or more of trimethylamine hydrochloride, N,N-diethylmethylammonium trifluoromethane sulfonate, and triethylammonium hydrochloride;

[0115] In one embodiment, the quaternary phosphonium-based ionic liquid cation comprises alkyltributylphosphonium, wherein the alkyl group is selected from ethyl, butyl, hexyl, or octyl. The anion is selected from bromine, tetrafluoroboric acid, or bis(trifluoromethanesulfonyl)imide.

[0116] Preferably, the quaternary phosphonium ionic liquid is selected from one or more of methyltributylphosphonium bis(trifluoromethanesulfonyl)imide, ethyltributylphosphonium bis(trifluoromethanesulfonyl)imide salt, propyltributylphosphonium bis(trifluoromethanesulfonyl)imide salt, N-hexylquaternary ammonium bis(trifluoromethanesulfonyl)imide salt, N-trimethyl-N-n-pentylquaternary ammonium trifluoromethanesulfonylimide salt, and N-trimethyl-N-n-butylquaternary ammonium trifluoromethanesulfonylimide salt.

[0117] In one embodiment, the pyrrolidine-based ionic liquid cation includes N-alkyl-N-methylpyrrolidine, wherein the alkyl group is selected from ethyl, propyl, butyl, hexyl, or octyl; and the anion is selected from bromine, tetrafluoroboric acid, hexafluorophosphate, or bis(trifluoromethanesulfonyl)imide.

[0118] Preferably, the pyrrolidine ionic liquid is selected from one or more of N-ethyl-N-methylpyrrolidine bis(trifluoromethanesulfonyl)imide salt, N-propyl-N-methylpyrrolidine bis(trifluoromethanesulfonyl)imide salt, N-butyl-N-methylpyrrolidine bis(trifluoromethanesulfonyl)imide salt, and N-methyl-N-propylpyrrolidineonium bis(trifluoromethanesulfonyl)imide salt.

[0119] In one embodiment, the piperidine-based ionic liquid cation includes N-alkyl-N-methylpiperidine, wherein the alkyl group is selected from ethyl, propyl, butyl, hexyl, or octyl; and the anion is selected from bromine, tetrafluoroboric acid, hexafluorophosphate, and bis(trifluoromethanesulfonyl)imide.

[0120] Preferably, the piperidine ionic liquid is selected from one or more of N-ethyl-N-methylpiperidine bis(trifluoromethanesulfonyl)imine salt, N-propyl-N-methylpiperidine bis(trifluoromethanesulfonyl)imine salt, and N-butyl-N-methylpiperidine bis(trifluoromethanesulfonyl)imine salt.

[0121] In one embodiment, the concentration of the lithium salt in the electrolyte is 0.5 mol / L to 5 mol / L.

[0122] In one embodiment, the positive electrode includes a positive electrode active material selected from one or more of lithium nickel cobalt manganese oxide, NCA, NCMA, lithium iron manganese phosphate, lithium iron phosphate, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium lithium manganese-based oxide, lithium nickel manganese oxide, and lithium vanadium oxide phosphate.

[0123] The negative electrode includes a negative electrode active material, which is selected from one or more of graphite, LTO, Si, silicon suboxide, silicon dioxide, Si-C, lithium metal, lithium alloy, Sn, Sn-C, SnO, and tin alloy.

[0124] The negative electrode may also contain only a current collector, which may be pure copper or a copper composite current collector.

[0125] The composite current collector includes a polymer base film and a conductive layer. The conductive layer is on both sides of the polymer base film. The polymer base film is selected from polyethylene, polyethylene terephthalate, polyimide, polypropylene, polyethylene, polyamide, polyphenylene sulfide or a combination thereof, and has a thickness of 1 to 300 μm.

[0126] The conductive layer is made of copper and has a thickness of 0.01–100 μm.

[0127] On the other hand, one embodiment of this application provides an electrical device including a semi-solid battery as described in any of the above claims. It should be noted that the semi-solid battery can be a liquid, semi-solid laminated, wound, or cylindrical semi-solid battery.

[0128] The present application will be further illustrated by the following examples.

[0129] Example 1

[0130] This embodiment illustrates the electrolyte membrane and its preparation method disclosed in this application, as well as the semi-solid-state battery, and includes the following operational steps:

[0131] Electrolyte membrane: Polyethylene oxide and lithium salt bis(trifluoromethanesulfonyl)imide lithium are dispersed in a mixed solvent. The mass ratio of the first solvent acetonitrile and the second solvent butyl butyrate in the mixed solvent is 1:1. Then, inorganic solid electrolyte Li2MnCl4 is added, and the mixture is cast onto a substrate. After drying at 100℃ and 0MPa for 12h to remove the mixed solvent, the electrolyte membrane is obtained.

[0132] The molar ratio of polymer monomer to lithium salt is 10:1, the inorganic solid electrolyte accounts for 3% of the total mass of the polymer and lithium salt, and the mass of the mixed solvent is 7 times the mass of the polymer. The average particle size of Li₂MnCl₄ is 200 nm.

[0133] Preparation of positive electrode

[0134] The positive electrode active material NCM811, conductive carbon black Super-P, and binder polyvinylidene fluoride (PVDF) were mixed in a mass ratio of 93:4:3, and then dispersed in an appropriate amount of N-methyl-2-pyrrolidone (NMP) to obtain the positive electrode slurry. The obtained slurry was uniformly coated on both sides of an aluminum foil, and after drying, calendering, and vacuum drying, aluminum leads were welded on using an ultrasonic welding machine to obtain the positive electrode sheet with a thickness between 120-150 μm.

[0135] Preparation of negative electrode

[0136] The negative electrode uses a metallic lithium negative electrode.

[0137] Preparation of electrolyte

[0138] The fourth solvent, ethylene carbonate, and methyl ethyl carbonate, were mixed in a 1:1 mass ratio. The first additive, tripropynyl phosphate, and the second additive, vinylene carbonate, were added to the solvent and dispersed. Then, lithium hexafluorophosphate (LiPF6) was added at a concentration of 1 mol / L. The content of the first additive, tripropynyl phosphate, in the electrolyte was 1%, and the content of the second additive in the electrolyte was 0.5%.

[0139] Cell manufacturing

[0140] An electrolyte membrane is placed between the positive and negative electrode sheets prepared above. Then, the sandwich structure consisting of the positive electrode sheet, negative electrode sheet and electrolyte membrane is stacked and packaged with an aluminum-plastic film to produce a soft-pack battery cell with a capacity of 1Ah ready for electrolyte injection.

[0141] Semi-solid batteries are obtained by injecting electrolyte and forming the cells.

[0142] Examples 2-19

[0143] Examples 2-19 illustrate the electrolyte membrane disclosed in this application, including most of the operating steps in Example 1 above, except that the formulation in Table 1 is used.

[0144] Table 1

[0145] Examples 20-28

[0146] Examples 20-28 illustrate the preparation method of the electrolyte membrane disclosed in this application, including most of the operation steps in Example 1 above, except that the formulation in Table 2 is used.

[0147] Table 2

[0148] Examples 29-33

[0149] Examples 29-33 illustrate the semi-solid-state battery disclosed in this application, including most of the operating steps in Example 1 above, except that the formulation in Table 3 is used.

[0150] Table 3

[0151] Example 34

[0152] This embodiment illustrates the electrolyte membrane and its preparation method disclosed in this application, as well as the semi-solid-state battery. It includes most of the operational steps in Embodiment 1 above, except that the preparation of the electrolyte membrane includes the following steps:

[0153] Polyethylene oxide (PE), lithium hexafluorophosphate (LiPF6), ethylene carbonate (ethylene carbonate), and Li₂MnCl₄ (Li₂MnCl₄) were mixed uniformly to obtain a mixture. The mass of the plasticizer was 10% of the mass of the polymer.

[0154] The mixture is hot-pressed at 200°C and 50MPa to obtain a film preform.

[0155] The plasticizer is extracted from the membrane preform using a third solvent, acetone, to obtain an electrolyte membrane.

[0156] Comparative Examples 1-2

[0157] Comparative Examples 1 and 2 are used to illustrate the electrolyte membrane and its preparation method disclosed in this application, including most of the operation steps in Example 1, except that the formulations in Tables 1 and 2 are used.

[0158] Comparative Example 3

[0159] Comparative Example 3 is used to illustrate the electrolyte membrane and its preparation method disclosed in this application. It includes most of the operational steps in Example 1 above, except that the preparation of the electrolyte membrane includes the following steps:

[0160] Polyethylene oxide and lithium salt bis(trifluoromethanesulfonyl)imide are dispersed in a mixed solvent. The mass ratio of the first solvent acetonitrile and the second solvent butyl butyrate in the mixed solvent is 1:1. After mixing, the mixture is cast onto a substrate to form a polymer electrolyte membrane.

[0161] Inorganic solid electrolyte Li2MnCl4 and binder PVDF are mixed to obtain a mixture. The mixture is sheared to fibrousize the binder. The mixture is then rolled to form an inorganic solid electrolyte membrane. The inorganic solid electrolyte membrane is then combined with a polymer electrolyte membrane. Finally, the electrolyte membrane is obtained by drying at 100℃ and 0MPa for 12h to remove the mixed solvent.

[0162] Performance testing

[0163] I. The following performance tests were performed on the semi-solid-state batteries prepared in Examples 1-33 and the comparative examples above:

[0164] 1. Charge-discharge test: The lithium-ion battery prepared above was charged at 0.1C in the range of 2.75-4.2V, and then left to rest for 5 minutes. After that, it was discharged at 0.1C and left to rest for 30 minutes. The capacity retention rate after 100 cycles was recorded.

[0165] 2. Ionic conductivity measurement: The electrolyte membrane is sandwiched between two stainless steel sheets and placed in the casing of a 2032 battery. The ionic conductivity is measured using an electrochemical impedance spectroscopy instrument. The formula is: σ = L / AR, where L is the thickness of the electrolyte membrane, A is the room temperature area of ​​the stainless steel sheet, and R is the measured impedance.

[0166] 3. Electrolyte membrane mechanical property testing:

[0167] Multiple rectangular specimens of uniform size were cut from the porous polymer membrane, ensuring that the edges of the specimens were smooth and free of cracks. The specimen dimensions were cut according to ASTM D882 standard. The specimens were placed in a standard test environment (temperature 23℃±2℃, relative humidity 50%±5%) for at least 24 hours to equilibrate and avoid the influence of the environment on the membrane performance. The membrane specimens were fixed on the fixture of the tensile testing machine, ensuring that their edges were aligned and wrinkle-free. The tensile speed was set, the tensile testing machine was started, and the force-displacement data during the tensile process were recorded. When the specimen broke, the force and elongation at the fracture point were recorded.

[0168] 4. Breathability test:

[0169] Cut a sample of appropriate size from the porous polymer membrane, ensuring the edges are smooth and crack-free. Equilibrate the sample for 24 hours under standard experimental conditions (temperature 23℃±2℃, relative humidity 50%±5%) to minimize environmental influences. Fix the membrane sample onto the sample holder of the gas permeability meter, ensuring the membrane is wrinkle-free. Set the test pressure (e.g., 100 kPa), begin introducing a specific gas (such as nitrogen or air), and maintain a constant pressure. Record the volumetric flow rate of the gas through the membrane per unit time (typically in cm³). 3 ( / min), and maintain the stability of the data.

[0170] The test results are shown in Table 4.

[0171] Table 4

[0172] As shown in Table 4, the test results of Examples 1-6 and Comparative Example 1 indicate that adding an inorganic solid electrolyte to the electrolyte membrane improves its ionic conductivity and further enhances the battery's capacity retention. The test results of Examples 1 and 9-13 show that excessively large inorganic solid electrolyte particles reduce the tensile strength of the electrolyte membrane, affecting its mechanical properties. The test results of Examples 1 and 14-17 show that as the molar ratio of polymer to lithium salt changes, the battery's conductivity, the tensile strength of the electrolyte membrane, and its ionic conductivity are all affected. When the polymer content is too high, the tensile strength is high, but the ionic conductivity is low, thus deteriorating the battery's capacity retention. Conversely, when the polymer content is too low, the tensile strength is low, but the ionic conductivity is high.

[0173] The test results from Examples 1, 24-26, and Comparative Example 2 show that during the preparation of the electrolyte membrane, when the content of the second solvent is excessive, the tensile strength and permeability of the electrolyte membrane are significantly reduced. When the content of the first solvent is excessive, the permeability of the porous polymer electrolyte membrane is relatively high, indicating that the pore size of the porous polymer electrolyte membrane is relatively large, which in turn affects the capacity retention rate of the battery.

[0174] The test results of Examples 1, 29-33 show that the electrolyte membrane is suitable for electrolytes in different systems.

[0175] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An electrolyte membrane, characterized in that, It includes a polymer electrolyte base membrane and an inorganic solid electrolyte. The polymer electrolyte base membrane is a porous film and includes a polymer and a lithium salt. The inorganic solid electrolyte is distributed in the polymer electrolyte base membrane in a particulate form.

2. The electrolyte membrane according to claim 1, characterized in that, The inorganic solid electrolyte is selected from halide solid electrolytes.

3. The electrolyte membrane according to claim 2, characterized in that, The mass of the halide solid electrolyte is 0.1% to 10% of the mass of the polymer electrolyte base membrane.

4. The electrolyte membrane according to claim 2, characterized in that, The halide solid electrolyte is selected from Li a (M b )X c X' d Wherein, M is selected from one or more of Ga, Y, In, Mg, Sr, Sc, Sn, Pb, Ti, Zr, Hf, Nb, Ta, W, Fe, Ru, Al, and lanthanide metals; X is selected from one or more of halogens; X' is selected from one or more of halide ions, N ions, oxygen-containing anion groups, and pseudohalide anions; 0.5≤a≤5, 0.2≤b≤4, c+d=a+bε, where ε is the weighted average valence of element M.

5. The electrolyte membrane according to claim 4, characterized in that, The oxygen-containing anion group is selected from O 2- S 2- CN - CO3 2- PO4 3- P2O7 4- SO4 2- One or more of the following; the pseudohalide anion is selected from SCN. - PF6 - NH2 - AlF4 - or BF4 - One or more of them.

6. The electrolyte membrane according to claim 4, characterized in that, The halide solid electrolyte is selected from Li₂MnCl₄, Li₂ZnCl₄, Li₂ZrOCl₄, LiYbF₄, LiAlF₄, Li₃YCl₆, Li₃InCl₆, and Li₃InCl₄. 5.5 F 0.5 Li3TaCl6, Li 0.388 Ta 0.238 La 0.475 One or more of Cl3 and Li6CoCl8.

7. The electrolyte membrane according to any one of claims 1 to 6, characterized in that, The inorganic solid electrolyte has a particle size of 5 nm to 3 μm.

8. The electrolyte membrane according to claim 1, characterized in that, At least one of the following conditions must be met: The permeability of the electrolyte membrane is 50–2000 s / 100cc·in. 2 1.22 kPa; The pore size of the electrolyte membrane is 100 nm to 50 μm; The porosity of the electrolyte membrane is 5% to 70%.

9. The electrolyte membrane according to claim 1, characterized in that, The molar ratio of the polymer to the lithium salt is (5:1) to (20:1).

10. The electrolyte membrane according to claim 9, characterized in that, The polymer is selected from at least one of polyethylene oxide, polyacrylate, polyvinylidene fluoride, polyvinylidene fluoride hexafluoropropylene copolymer, polysiloxane, polyethylene glycol, sodium polystyrene sulfonate, polysulfone, polyethersulfone, polypropylene carbonate, polymethyl methacrylate, polyacrylonitrile, and polyimide. And / or, the lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloyl)borate, and lithium difluorooxaloylborate.

11. The electrolyte membrane according to claim 1, characterized in that, The thickness of the electrolyte membrane is 5 μm to 300 μm.

12. A method for preparing an electrolyte membrane according to any one of claims 1 to 11, characterized in that, Includes the following steps: The polymer and the lithium salt are dispersed in a mixed solvent, then an inorganic solid electrolyte is added, and after mixing, the mixture is cast onto a substrate. After drying to remove the mixed solvent, an electrolyte membrane is obtained. The mixed solvent includes a first solvent that is miscible with the polymer and a second solvent that is insoluble with the polymer.

13. The method for preparing the electrolyte membrane according to claim 12, characterized in that, The mass of the mixed solvent is 3 to 15 times the mass of the polymer, and the mass ratio of the first solvent to the second solvent is 1:10 to 10:

1.

14. The method for preparing the electrolyte membrane according to claim 12, characterized in that, The first solvent is selected from one or more of acetonitrile, acetone, ethyl acetate, butanone, diethyl ether, hexane, n-heptane, chloroform, tetrahydrofuran, N,N-dimethylacetamide, N,N-dimethylacetamide, 2,2,2-trifluoro-N,N-dimethylformamide, and N-methylpyrrolidone; The second solvent is selected from one or more of butyl butyrate, ethyl butyrate, isobutyl isobutyrate, ethanol, and butanol.

15. The method for preparing the electrolyte membrane according to claim 12, characterized in that, The drying temperature is 60–160°C, the drying time is 6–24 h, and the relative vacuum degree during drying is -0.1–0 MPa.

16. A method for preparing an electrolyte membrane as described in any one of claims 1 to 11, characterized in that, Includes the following steps: The polymer, lithium salt, plasticizer, and inorganic solid electrolyte are mixed evenly to obtain a mixture. The mixture is hot-pressed to obtain a film preform; The plasticizer is extracted from the membrane preform using a third solvent to obtain an electrolyte membrane.

17. The method for preparing the electrolyte membrane according to claim 16, characterized in that, The hot pressing temperature is 100–400℃ and the pressure is 10–300 MPa.

18. The method for preparing the electrolyte membrane according to claim 16, characterized in that, The plasticizer is selected from one or more of ethylene carbonate, ethyl methyl carbonate, diethyl carbonate, propylene carbonate, N,N-dimethylacetamide, 2,2,2-trifluoro-N,N-dimethylformamide, and dibutyl phthalate. And / or, the third solvent is selected from one or more of acetonitrile, acetone, ethyl acetate, diethyl ether, hexane, chloroform, tetrahydrofuran, and N-methylpyrrolidone.

19. The method for preparing the electrolyte membrane according to claim 16, characterized in that, The plasticizer accounts for 5% to 40% of the polymer's mass.

20. A semi-solid-state battery, characterized in that, The electrolyte comprises a positive electrode, a negative electrode, an electrolyte, and an electrolyte membrane as described in any one of claims 1 to 11; or, it comprises an electrolyte and an electrolyte membrane prepared by the method for preparing an electrolyte membrane as described in any one of claims 12 to 20; wherein the electrolyte membrane is located between the positive electrode and the negative electrode.

21. The semi-solid-state battery according to claim 20, characterized in that, The electrolyte comprises a fourth solvent, a lithium salt, a first additive, and a second additive; The fourth solvent is selected from at least one of ethylene carbonate, propylene carbonate, butene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, dimethyl sulfite, diethyl sulfite, dipropyl sulfite, ethylene sulfite, methyl acetate, ethyl formate, ethyl propionate, methyl propionate, ethylene glycol n-butyl ether, methyl butyl ether, methyl tert-butyl ether, dibutyl ether, ethylene glycol dimethyl ether, 1,3-dioxolane, tetraethylene glycol dimethyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether. The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(fluorosulfonyl)borate, and lithium difluorooxalate borate. The first additive is selected from at least one of the following: tripropynyl phosphate, 4-nitrobenzene trifluoroacetic acid, fluoroethers such as 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, 1,3-propanesulfonyl lactone, vinyl sulfate, toluene, 1,2-xylene, 1,3-xylene, 1,4-xylene, fluorobenzene, 1,2-difluorobenzene, 1,3-difluorobenzene, 1,4-difluorobenzene, 1,2,4-trifluorobenzene, 1,3,5-trifluorobenzene, 1,2,3,4-tetrafluorobenzene, 1,2,3,5-tetrafluorobenzene, 1,2,4,5-tetrafluorobenzene, pentafluorobenzene, and hexafluorobenzene; The second additive is selected from at least one of vinylene carbonate, fluoroethylene carbonate, and LiNO3.

22. The semi-solid-state battery according to claim 21, characterized in that, The volume ratio of the fourth solvent to the first additive is (1:10) to (10:1); And / or, the mass content of the second additive in the electrolyte is 0.1% to 10%.

23. The semi-solid-state battery according to claim 20, characterized in that, The electrolyte comprises an ester-based organic solvent and a lithium salt, wherein the ester-based organic solvent is selected from at least one of ethylene carbonate, propylene carbonate, butene carbonate, dimethyl carbonate, diethyl carbonate, methyl ethyl carbonate, methyl propyl carbonate, dimethyl sulfite, diethyl sulfite, dipropyl sulfite, ethylene sulfite, methyl acetate, ethyl acetate, ethyl formate, ethyl propionate, and methyl propionate. The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloacetate borate), and lithium difluorooxaloacetate borate.

24. The semi-solid-state battery according to claim 20, characterized in that, The electrolyte comprises an ether-based organic solvent and a lithium salt, wherein the ether-based organic solvent is selected from at least one of ethylene glycol n-butyl ether, methyl butyl ether, methyl tert-butyl ether, dibutyl ether, ethylene glycol dimethyl ether, 1,3-dioxolane, tetraethylene glycol dimethyl ether, 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether; The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloacetate borate), and lithium difluorooxaloacetate borate.

25. The semi-solid-state battery according to claim 20, characterized in that, The electrolyte comprises an ionic liquid and a lithium salt, wherein the ionic liquid is selected from one or more of imidazole ionic liquids, pyridine ionic liquids, quaternary ammonium ionic liquids, quaternary phosphorus ionic liquids, pyrrolidine ionic liquids, and piperidine ionic liquids; The lithium salt is selected from at least one of lithium hexafluorophosphate, lithium hexafluoroarsenate, lithium tetrafluoroborate, lithium hexafluoroantimonyate, lithium bis(trifluoromethanesulfonate imide), lithium trifluoromethanesulfonate, lithium bis(fluorosulfonyl)imide, lithium perchlorate, lithium iodide, lithium magnesium bis(fluorosulfonyl)imide, lithium bis(oxaloyl)borate, and lithium difluorooxaloylborate.

26. The semi-solid-state battery according to any one of claims 21 to 25, characterized in that, The concentration of the lithium salt in the electrolyte is 0.5 mol / L to 5 mol / L.

27. The semi-solid-state battery according to claim 20, characterized in that, The positive electrode includes a positive electrode active material, which is selected from one or more of lithium nickel cobalt manganese oxide, NCA, NCMA, lithium iron manganese phosphate, lithium iron phosphate, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium lithium manganese-based oxide, lithium nickel manganese oxide, and lithium vanadium oxide phosphate. The negative electrode includes a negative electrode active material, which is selected from one or more of graphite, LTO, Si, silicon suboxide, silicon dioxide, Si-C, lithium metal, lithium alloy, Sn, Sn-C, SnO, and tin alloy.

28. An electrical appliance, characterized in that, Includes the semi-solid-state battery as described in any one of claims 20 to 27.

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