Layered organic solid-state electrolyte membrane, preparation method therefor, and use thereof

Abstract

The present invention relates to the field of batteries. Specifically disclosed are a layered organic solid-state electrolyte membrane, a preparation method therefor, and a use thereof. The solid-state electrolyte membrane comprises a layered material and an electrolyte salt, and the electrolyte salt is loaded on the layered material. The layered material has at least two organic molecular layers. Each organic molecular layer has a porous structure. Each organic molecular layer is formed by assembling small molecules via at least one selected from a hydrogen bond, a covalent bond, and an intermolecular force. The small molecules are selected from at least one of an aromatic compound, a triazine ring-containing compound, and an amide group-containing compound. The solid-state electrolyte membrane of the present invention has an extremely high ionic conductivity, which can reach up to approximately 10 mS cm-1. Furthermore, a solid-state battery prepared from the solid-state electrolyte membrane of the present invention can cycle for a long-time and stably at room temperature.

Description

A layered organic solid electrolyte membrane, its preparation method and application Technical Field

[0001] This invention belongs to the field of batteries, specifically relating to a layered organic solid electrolyte membrane, its preparation method, and its application. Background Technology

[0002] High-energy-density solid-state lithium batteries are crucial for the development of electric vehicles, energy storage devices, and consumer electronics. Solid electrolytes are a key component of solid-state lithium batteries, and their lithium-ion conductivity determines the battery's performance. Common solid electrolyte materials can be divided into organic and inorganic electrolyte materials. Organic electrolyte materials have poor room-temperature ionic conductivity, while inorganic solid-state electrolyte materials suffer from high contact resistance and require high external pressure, thus limiting their development. In recent years, layered materials, as an emerging material with two-dimensional interconnected ion channels, have attracted widespread attention due to their excellent interlayer ion conduction capabilities, particularly in energy storage, water purification, catalysis, biosynthesis, and sensing. Therefore, layered materials hold promise as a new class of solid-state ion conductor framework materials; however, when fabricated into solid electrolyte membranes, they often exhibit low lithium-ion conductivity.

[0003] Currently, most layered solid electrolytes are formed into films using mechanical methods such as hot pressing and cold pressing before being assembled into solid-state batteries. However, this method results in randomly oriented layered materials in the electrolyte film, preventing the formation of a connected ion-conducting network and limiting the intrinsic ionic conductivity of the layered materials, which can only reach 1.5 × 10⁻⁶ at 100°C. -5 S cm -1 It is far below the demand.

[0004] In recent years, studies have explored methods to create longitudinal channels by ultrasonically exfoliating layered materials and filtering two-dimensional nanosheets for reassembly, utilizing the gaps at the nanosheet edges. However, due to the irregular distribution during the nanoassembly process and the irregular gaps at the nanosheet edges, the longitudinal channels become tortuous, the ion transport path is lengthened, and the ionic conductivity is reduced. Furthermore, the size of the edge gaps cannot be effectively controlled. Therefore, achieving high ionic conductivity in the longitudinal direction of layered materials is crucial for the application of high-performance layered material-based solid electrolytes. Layered materials possess horizontal two-dimensional channels but lack longitudinal channels, and their inability to conduct lithium ions longitudinally greatly hinders their application as solid electrolyte membranes. Moreover, existing methods cannot obtain horizontally oriented layered material electrolyte membranes to achieve directional ion pathways from the positive to the negative electrode in the two-dimensional direction; they typically exhibit random orientation distributions, resulting in low lithium-ion conductivity in layered solid electrolyte membranes.

[0005] Summary of the Invention

[0006] In order to overcome at least one of the technical problems existing in the prior art, one of the objectives of the present invention is to provide a solid electrolyte membrane.

[0007] The second objective of this invention is to provide a method for preparing a solid electrolyte membrane.

[0008] The third objective of this invention is to provide a solid-state battery.

[0009] The fourth objective of this invention is to provide the application of the above-mentioned solid electrolyte membrane and solid battery in electronic devices.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0011] A first aspect of the present invention provides a solid electrolyte membrane comprising a layered material and an electrolyte salt, the electrolyte salt being loaded on the layered material; the layered material having at least two organic molecular layers; the organic molecular layers having a porous structure, the organic molecular layers being assembled from small molecules by at least one selected from hydrogen bonds, covalent bonds, and intermolecular forces; the small molecules being selected from at least one selected from aromatic compounds, compounds containing triazine rings, and compounds containing amide groups.

[0012] In one embodiment of the present invention, the pore size of the organic molecular layer is 0.3 to 1 nm.

[0013] In one embodiment of the present invention, the pore density of the organic molecular layer is 2 × 10⁻⁶. 5 ~5×10 6 pcs / cm 2 .

[0014] In one embodiment of the present invention, the distance between two adjacent organic molecular layers in the layered material is 0.1 to 1 nm.

[0015] In one embodiment of the present invention, the small molecule is selected from at least two of the following: trimellitic acid, pyrogallol, aniline, 1,3,5-trinitrobenzene, 1,3,5-trichloro-2,4,6-trinitrobenzene, phenol, benzenesulfonic acid, p-dibromobenzene, 2,7-bis(bromomethyl)naphthalene, 1-amino-5-naphthol, 1,5-naphthalenedisulfonic acid, 1,3,6-trichloronaphthalene, 1,3,5-trichlorobenzene, melamine, melamine, uric acid, cyanuric acid, urea, and thiourea.

[0016] In one embodiment of the present invention, the small molecule includes compound A and compound B; compound A is selected from at least one of melamine, melamine, and p-dibromobenzene; compound B is selected from at least one of trimellitic acid, 1,3,5-trichloro-2,4,6-trinitrobenzene, trimellitic acid, and urea.

[0017] In one embodiment of the present invention, the mass ratio of compound A to compound B is (0.3-4):1.

[0018] In one embodiment of the present invention, the mass of the layered material is 70-90% of the mass of the solid electrolyte membrane.

[0019] In one embodiment of the present invention, the mass ratio of the layered material to the electrolyte salt is 1:(0.1 to 1.5).

[0020] In one embodiment of the present invention, the solid electrolyte membrane further includes a binder; the mass ratio of the layered material to the binder is 1:(0.01 to 0.3).

[0021] In one embodiment of the present invention, the electrolyte salt is selected from at least one of lithium chloride, lithium bromide, lithium hexafluorophosphate, lithium nitrate, lithium perchlorate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, lithium fluoroalkyl phosphate, lithium dioxaborate, lithium difluorooxaborate, and lithium tetrafluoroborate.

[0022] In one embodiment of the present invention, the electrolyte salt is selected from at least one of sodium chloride, sodium bromide, sodium hexafluorophosphate, sodium nitrate, sodium perchlorate, sodium bis(trifluoromethylsulfonyl)imide, sodium bis(fluorosulfonyl)imide, sodium fluoroalkyl phosphate, sodium dioxolane borate, sodium difluorooxolane borate, and sodium tetrafluoroborate.

[0023] In one embodiment of the present invention, the electrolyte salt is selected from at least one of potassium chloride, potassium bromide, potassium hexafluorophosphate, potassium nitrate, potassium perchlorate, potassium bis(trifluoromethylsulfonyl)imide, potassium bis(fluorosulfonyl)imide, potassium fluoroalkyl phosphate, potassium dioxalate borate, and potassium tetrafluoroborate.

[0024] In some embodiments of the present invention, the adhesive includes at least one of polytetrafluoroethylene, polyvinylidene fluoride, sodium alginate, styrene-butadiene rubber, carboxymethyl cellulose, polyethylene oxide, polyethylene glycol, lignin, and cellulose.

[0025] In one embodiment of the present invention, the thickness of the solid electrolyte membrane is 50 to 1000 μm.

[0026] In one embodiment of the present invention, the ionic conductivity of the solid electrolyte membrane measured at 25°C is 0.5-10 mS / cm. -1 .

[0027] The second aspect of the present invention provides a method for preparing the solid electrolyte membrane described in the first aspect of the present invention, comprising the following steps:

[0028] S1: Mix and grind the raw materials, including small molecules, to obtain the layered material;

[0029] S2: Mix the raw materials including the layered material, electrolyte salt, and optionally added binder, and then form a film to obtain the solid electrolyte membrane.

[0030] In one embodiment of the present invention, step S1 is: ball milling the raw material including small molecules and lubricating solvent, and then drying it to obtain the layered material.

[0031] In one embodiment of the present invention, the lubricating solvent includes at least one of water and DMSO.

[0032] In one embodiment of the present invention, the mass ratio of the small molecule to the lubricating solvent is 1:(0.5 to 1.5).

[0033] In one embodiment of the present invention, the drying step is to first dry in an air atmosphere and then dry in a vacuum atmosphere.

[0034] In one embodiment of the present invention, the drying temperature under the air atmosphere is 70-90°C.

[0035] In one embodiment of the present invention, the drying temperature in the vacuum atmosphere drying step is 70-110°C.

[0036] In one embodiment of the present invention, the drying time in the vacuum atmosphere drying step is 10 to 48 hours.

[0037] In one embodiment of the present invention, the grinding step is performed using ball milling.

[0038] In one embodiment of the present invention, the ball mill rotation speed is 400-1000 rpm.

[0039] In one embodiment of the present invention, the ball milling time is 0.5 to 5 hours.

[0040] In one embodiment of the present invention, the ball milling step is performed using mixed zirconia grinding balls with diameters of 3 mm and 5 mm at a mass ratio of (1.8 to 2.2):1.

[0041] A third aspect of the present invention provides a solid-state battery comprising the solid electrolyte membrane described in the first aspect of the present invention.

[0042] The fourth aspect of the present invention provides the application of the solid electrolyte membrane described in the first aspect of the present invention and / or the solid battery described in the third aspect of the present invention in electronic devices.

[0043] The beneficial effects of this invention are: by controlling the structure of small molecules and assembling them into a two-dimensional layered material, this invention enables the layered material to simultaneously possess interlayer ion transport channels and longitudinal translayer ion transport channels. Loading electrolyte salts onto this layered material results in a solid electrolyte membrane with extremely high ionic conductivity, reaching up to 10 mS / cm. -1 Approximately. Furthermore, the solid-state battery fabricated from the solid electrolyte membrane of this invention can achieve long-term stable cycling at room temperature. Attached Figure Description

[0044] Figure 1 is a schematic diagram of the ion conduction principle of a solid-state battery composed of a solid electrolyte in the prior art and embodiments of the present invention.

[0045] Figure 2 is a physical image of the layered material in Example 1.

[0046] Figure 3 is a schematic diagram of the planar structure of the layered material in Example 1.

[0047] Figure 4 is a schematic diagram of the longitudinal structure of the layered material in Example 1.

[0048] Figure 5 is a TEM image of the layered material in Example 1.

[0049] Figure 6 shows the AC impedance test diagram of the solid electrolyte membrane in Example 1.

[0050] Figure 7 shows the cycle performance test results of the solid-state battery in Example 10.

[0051] Figure 8 shows the AC impedance test results of the solid electrolyte membrane in Comparative Example 1. Detailed Implementation

[0052] The specific implementation of the present invention will be further described in detail below with reference to the accompanying drawings and examples, but the implementation and protection of the present invention are not limited thereto. It should be noted that any processes not specifically described in detail below are those that can be implemented or understood by those skilled in the art by referring to the prior art. Reagents or instruments used without specified manufacturers are all conventional products that can be purchased commercially.

[0053] In some embodiments of the present invention, a solid electrolyte membrane is provided, comprising a layered material and an electrolyte salt, wherein the electrolyte salt is loaded on the layered material; the layered material has at least two organic molecular layers; the organic molecular layers have a porous structure, and the organic molecular layers are assembled from small molecules through at least one selected from hydrogen bonds, covalent bonds, and intermolecular forces; the small molecules are selected from at least one selected from aromatic compounds, compounds containing triazine rings, and compounds containing amide groups. Each organic molecular layer in the solid electrolyte membrane of the present invention has a porous structure with many micropores, resembling a sieve and allowing metal ions (e.g., lithium ions, sodium ions, or potassium ions) to pass through. Furthermore, the layered material has gaps between adjacent organic molecular layers, forming two-dimensional ion channels in the horizontal direction, and in the vertical direction, continuous interlayer ion channels are formed by the micropores on the organic molecular layers (i.e., the porous structure of the organic molecular layers), greatly improving the ion conductivity of the solid electrolyte membrane in all directions and solving the problem of extremely low ion conductivity of existing two-dimensional layered materials as solid electrolytes.

[0054] In some embodiments of the present invention, the pore size of the organic molecular layer is 0.3–1 nm. In some specific embodiments of the present invention, the pore size of the organic molecular layer can be 0.3 nm, 0.4 nm, 0.5 nm, 0.6 nm, 0.7 nm, 0.8 nm, 0.9 nm, or 1 nm.

[0055] In some embodiments of the present invention, the pore density of the organic molecular layer is 2 × 10⁻⁶. 5 ~5×10 6 pcs / cm 2 In some specific embodiments of the present invention, the pore density of the organic molecular layer can be 2 × 10⁻⁶. 5 pcs / cm 2 3×10 5 pcs / cm 2 4×10 5 pcs / cm 2 5×10 5 pcs / cm 2 6×10 5 pcs / cm 2 7×10 5 pcs / cm 2 8×10 5 pcs / cm 2 9×10 5 pcs / cm 2 1×10 6 pcs / cm 2 1.5×10 6 pcs / cm 2 2×10 6 pcs / cm 22.5×10 6 pcs / cm 2 3×10 6 pcs / cm 2 3.5×10 6 pcs / cm 2 4×10 6 pcs / cm 2 4.5×10 6 pcs / cm 2 Or 5×10 6 pcs / cm 2 .

[0056] In some embodiments of the present invention, the distance between two adjacent organic molecular layers in the layered material is 0.1 to 1 nm. In some specific embodiments of the present invention, the distance between two adjacent organic molecular layers can be 0.1 nm, 0.2 nm, 0.3 nm, 0.4 nm, 0.5 nm, 0.6 nm, 0.7 nm, 0.8 nm, 0.9 nm or 1 nm.

[0057] In some embodiments of the present invention, the small molecule is selected from at least two of the following: trimellitic acid, pyrogallol, aniline, 1,3,5-trinitrobenzene, 1,3,5-trichloro-2,4,6-trinitrobenzene, phenol, benzenesulfonic acid, p-dibromobenzene, 2,7-bis(bromomethyl)naphthalene, 1-amino-5-naphthol, 1,5-naphthalenedisulfonic acid, 1,3,6-trichloronaphthalene, 1,3,5-trichlorobenzene, melamine, melamine, uric acid, cyanuric acid, urea, and thiourea.

[0058] In some embodiments of the present invention, the small molecule includes compound A and compound B; compound A is selected from at least one of melamine, melamine, and p-dibromobenzene; compound B is selected from at least one of trimellitic acid, 1,3,5-trichloro-2,4,6-trinitrobenzene, trimellitic acid, and urea.

[0059] In some embodiments of the present invention, the mass ratio of compound A to compound B is (0.3-4):1. In some specific embodiments of the present invention, the mass ratio of compound A to compound B is 0.3:1, 0.4:1, 0.5:1, 0.7:1, 0.8:1, 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1 or 4:1.

[0060] In some embodiments of the present invention, the mass of the layered material is 70% to 90% of the mass of the solid electrolyte membrane, for example, it can be selected from 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, or 90%.

[0061] In some embodiments of the present invention, the mass ratio of the layered material to the electrolyte salt is 1:(0.1 to 1.5). In some specific embodiments of the present invention, the mass ratio of the layered material to the electrolyte salt can be 1:0.1, 1:0.2, 1:0.3, 1:0.4, 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4, or 1:1.5.

[0062] In some embodiments of the present invention, the solid electrolyte membrane further includes a binder; the mass ratio of the layered material to the binder is 1:(0.01 to 0.3). In some specific embodiments of the present invention, the mass ratio of the layered material to the binder is 1:0.01, 1:0.05, 1:0.1, 1:0.15, 1:0.2, 1:0.25, or 1:0.3.

[0063] In some embodiments of the present invention, the electrolyte salt is selected from at least one of lithium chloride, lithium bromide, lithium hexafluorophosphate, lithium nitrate, lithium perchlorate, lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide, lithium fluoroalkyl phosphate, lithium dioxalate borate, lithium difluorooxalate borate, and lithium tetrafluoroborate.

[0064] In some embodiments of the present invention, the electrolyte salt is selected from at least one of sodium chloride, sodium bromide, sodium hexafluorophosphate, sodium nitrate, sodium perchlorate, sodium bis(trifluoromethylsulfonyl)imide, sodium bis(fluorosulfonyl)imide, sodium fluoroalkyl phosphate, sodium dioxolane borate, sodium difluorooxolane borate, and sodium tetrafluoroborate.

[0065] In some embodiments of the present invention, the electrolyte salt is selected from at least one of potassium chloride, potassium bromide, potassium hexafluorophosphate, potassium nitrate, potassium perchlorate, potassium bis(trifluoromethylsulfonyl)imide, potassium bis(fluorosulfonyl)imide, potassium fluoroalkyl phosphate, potassium dioxalate borate, and potassium tetrafluoroborate.

[0066] In some embodiments of the present invention, the adhesive includes at least one of polytetrafluoroethylene, polyvinylidene fluoride, sodium alginate, styrene-butadiene rubber, carboxymethyl cellulose, polyethylene oxide, polyethylene glycol, lignin, and cellulose.

[0067] In some embodiments of the present invention, the thickness of the solid electrolyte membrane is 50–1000 μm. In some specific embodiments of the present invention, the thickness of the solid electrolyte membrane is 50 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, or 1000 μm.

[0068] In some embodiments of the present invention, the ionic conductivity of the solid electrolyte membrane measured at 25°C is 0.5-10 mS / cm. -1 .

[0069] In some embodiments of the present invention, the present invention provides a method for preparing the above-mentioned solid electrolyte membrane, comprising the following steps:

[0070] S1: Mix and grind raw materials including small molecules to obtain layered materials;

[0071] S2: Mix raw materials including layered materials, electrolyte salts, and optionally added binders, and then form a film to obtain a solid electrolyte membrane.

[0072] In some embodiments of the present invention, step S1 is: ball milling the raw material including small molecules and lubricating solvent, and then drying it to obtain the layered material.

[0073] In some embodiments of the present invention, the lubricating solvent includes at least one of water and DMSO.

[0074] In some embodiments of the present invention, the mass ratio of the small molecule to the lubricating solvent is 1:(0.5 to 1.5); in some specific embodiments of the present invention, the mass ratio of the small molecule to the lubricating solvent can be 1:0.5, 1:0.6, 1:0.7, 1:0.8, 1:0.9, 1:1, 1:1.1, 1:1.2, 1:1.3, 1:1.4 or 1:1.5.

[0075] In some embodiments of the present invention, the drying step is to first dry in an air atmosphere and then dry in a vacuum atmosphere.

[0076] In some embodiments of the present invention, the drying temperature under air atmosphere is 70-90°C; in some specific embodiments of the present invention, the drying temperature under air atmosphere can be 70°C, 75°C, 80°C, 85°C or 90°C.

[0077] In some embodiments of the present invention, the drying temperature in the drying step under vacuum atmosphere is 70-110°C; in some specific embodiments of the present invention, the drying temperature in the drying step under vacuum atmosphere can be 70°C, 75°C, 80°C, 85°C, 90°C, 95°C, 100°C, 105°C or 110°C.

[0078] In some embodiments of the present invention, the drying time in the vacuum atmosphere drying step is 10 to 48 hours; in some specific embodiments of the present invention, the drying time in the vacuum atmosphere drying step can be 10 hours, 11 hours, 12 hours, 13 hours, 14 hours, 15 hours, 16 hours, 17 hours, 20 hours, 25 hours, 30 hours, 35 hours or 40 hours.

[0079] In some embodiments of the present invention, the grinding step is performed using ball milling.

[0080] In some embodiments of the present invention, the ball milling speed is 400 to 1000 rpm; in some specific embodiments of the present invention, the ball milling speed can be 400 rpm, 500 rpm, 600 rpm, 700 rpm, 800 rpm, 900 rpm or 1000 rpm.

[0081] In some embodiments of the present invention, the ball milling time is 0.5 to 5 hours; in some specific embodiments of the present invention, the ball milling time can be 0.5 hours, 0.8 hours, 1 hour, 1.5 hours, 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours or 5 hours.

[0082] In some embodiments of the present invention, the ball milling step is performed using mixed zirconia grinding balls with diameters of 3 mm and 5 mm at a mass ratio of (1.8 to 2.2):1.

[0083] In some embodiments of the present invention, step S2 is: mixing raw materials including layered materials, electrolyte salts, binders and organic solvents, evaporating some of the solvents, then casting the mixture onto a mold, removing the solvents, and forming a film to obtain a solid electrolyte membrane.

[0084] In some embodiments of the present invention, the organic solvent in step S2 includes at least one of N-methylpyrrolidone and carbonate solvents.

[0085] In some embodiments of the present invention, the present invention also provides a solid-state battery, including a positive electrode, a negative electrode and the above-described solid electrolyte membrane.

[0086] Figures 1(a) and 1(b) show schematic diagrams of the ion conduction principle of solid-state batteries using ordinary organic layered materials in the prior art and the solid-state battery of the present invention, respectively. As shown in Figure 1(a), in solid-state batteries made with ordinary organic layered materials in the prior art, lithium ions can only be transported along the horizontal channels between the layers of the solid electrolyte; ion conduction is not possible in the vertical direction (i.e., lithium ions do not conduct between different layers). Therefore, the ion conductivity of solid-state electrolytes made with ordinary layered organic materials in the prior art is extremely low. As shown in Figure 1(b), the layered material in the solid electrolyte membrane of the embodiment of the present invention not only has horizontal channels (where lithium ions conduct between adjacent organic molecular layers) but also vertical channels (i.e., an in-plane sieve structure, allowing lithium ions to pass through porous organic molecular layers, achieving cross-layer lithium ion transport). Therefore, the resulting solid electrolyte membrane has extremely high lithium ion conductivity, with a maximum room temperature (25°C) lithium ion conductivity of 10 mS / cm. -1 .

[0087] In some embodiments of the present invention, the solid-state battery is a lithium-ion solid-state battery, a sodium-ion solid-state battery, or a potassium-ion solid-state battery.

[0088] In some embodiments of the present invention, the present invention also provides the application of the above-described solid electrolyte membrane and the above-described solid battery in electronic devices with rechargeable batteries.

[0089] The implementation of the present invention will be further described in detail below with reference to specific embodiments:

[0090] Example 1

[0091] This example provides a layered organic solid electrolyte membrane, the preparation method of which includes the following steps:

[0092] (1) Melamine and trimellitic acid were weighed at a mass ratio of 1:1 and fed into a ball mill jar. Water was added as a lubricating solution. The mass ratio of the lubricating solution to trimellitic acid was 1:1, and the mass of the lubricating solution was 1g. Zirconia grinding balls were used. The mass ratio of the grinding balls to the material (i.e., melamine and trimellitic acid) was 1:5. The zirconia grinding balls used were grinding balls with diameters of 3mm and 5mm respectively. The mass ratio of the 3mm grinding balls to the 5mm grinding balls was 2:1. The ball milling speed was 900rpm and the ball milling time was 0.5h. After drying at 80℃, the material was transferred to vacuum drying at a temperature of 110℃ for 24h to obtain a layered material.

[0093] (2) Grind and mix 1g of layered material with an organic solvent containing lithium salt and binder. The lithium salt is 0.5g of lithium chloride, and the amount of binder is 0.15g. The binder is polyvinylidene fluoride binder. Then add 5mL of organic solvent N-methylpyrrolidone and stir for 6h. After the solvent evaporates, pour it into a mold and further evaporate the solvent to form a solid electrolyte membrane, which is the layered organic solid electrolyte membrane in this example with a thickness of 200μm. Its physical picture is shown in Figure 2.

[0094] Figures 3 and 4 show the planar and longitudinal structural schematics of the layered material in this example, constructed using three-dimensional reconstruction techniques from transmission electron microscopy. As can be seen from Figures 3 and 4, the interlayer spacing of the layered material in this example is 0.3–0.4 nm, and the longitudinal in-plane sieve pore size is 0.6–0.8 nm. Due to the different sizes of the small molecules (melamine and trimesic acid) and the effects of supramolecular forces, the small molecules cannot be tightly packed in the plane, leaving transplanar channels. These channels provide pathways for longitudinal transport across the two-dimensional layers, i.e., the in-plane sieve structure.

[0095] The morphology of the layered material prepared in this example was tested using transmission electron microscopy, and the specific test results are shown in Figure 5. As can be seen from Figure 5, the layered material prepared in this example has a sheet-like structure, and there are angstrom-level pores on the surface of the sheets.

[0096] The solid electrolyte membrane prepared in this example was sandwiched between two stainless steel sheets to test its AC impedance. The specific test results are shown in Figure 6. Then, the lithium-ion conductivity was calculated, and the room temperature (25℃) lithium-ion conductivity of the solid electrolyte membrane in this example was found to be 10 mS / cm. -1 .

[0097] Example 2

[0098] The only difference between the preparation method of the layered organic solid electrolyte membrane in this example and that in Example 1 is that melamine and trimesic acid with a mass ratio of 2:1 are used in step (1) of this example.

[0099] The room temperature (25°C) lithium-ion conductivity of the solid electrolyte membrane in this example was measured to be 8 mS / cm using the test method described in Example 1. -1 .

[0100] Example 3

[0101] The only difference between the preparation method of the layered organic solid electrolyte membrane in this example and that in Example 1 is that melamine and trimesic acid with a mass ratio of 3:1 are used in step (1) of this example.

[0102] The room temperature (25°C) lithium-ion conductivity of the solid electrolyte membrane in this example was measured to be 9 mS / cm using the test method described in Example 1. -1 .

[0103] Example 4

[0104] The only difference between the preparation method of the layered organic solid electrolyte membrane in this example and that in Example 1 is that melamine and trimesic acid with a mass ratio of 1:2 are used in step (1) of this example.

[0105] The room temperature (25°C) lithium-ion conductivity of the solid electrolyte membrane in this example was measured to be 4 mS / cm using the test method described in Example 1. -1 .

[0106] Example 5

[0107] The only difference between the preparation method of the layered organic solid electrolyte membrane in this example and that in Example 1 is that melamine and trimesic acid with a mass ratio of 1:3 are used in step (1) of this example.

[0108] The room temperature (25°C) lithium-ion conductivity of the solid electrolyte membrane in this example was measured to be 5 mS / cm using the test method described in Example 1.-1 .

[0109] Example 5

[0110] The only difference between the preparation method of the layered organic solid electrolyte membrane in this example and that in Example 1 is that melamine and 1,3,5-trichloro-2,4,6-trinitrobenzene are used in step (1) of this example in a mass ratio of 1:1.

[0111] The room temperature (25°C) lithium-ion conductivity of the solid electrolyte membrane in this example was measured to be 0.5 mS / cm using the test method described in Example 1. -1 .

[0112] Example 6

[0113] The only difference between the preparation method of the layered organic solid electrolyte membrane in this example and that in Example 1 is that in step (1) of this example, melamine and trimellitic acid are used in a mass ratio of 1:1.

[0114] The room temperature (25°C) lithium-ion conductivity of the solid electrolyte membrane in this example was measured to be 0.8 mS / cm using the test method described in Example 1. -1 .

[0115] Example 7

[0116] The only difference between the preparation method of the layered organic solid electrolyte membrane in this example and that in Example 1 is that in step (1) of this example, melamine and pyrogallol are used in a mass ratio of 1:1.

[0117] The room temperature (25°C) lithium-ion conductivity of the solid electrolyte membrane in this example was measured to be 1 mS / cm using the test method described in Example 1. -1 .

[0118] Example 8

[0119] The only difference between the preparation method of the layered organic solid electrolyte membrane in this example and that in Example 1 is that melamine, pyromellitic acid and urea are used in step (1) in this example in a mass ratio of 1:1:1.

[0120] The room temperature (25°C) lithium-ion conductivity of the solid electrolyte membrane in this example was measured to be 7 mS / cm using the test method described in Example 1. -1 .

[0121] Example 9

[0122] The only difference between the preparation method of the layered organic solid electrolyte membrane in this example and that in Example 1 is that in step (1) of this example, p-dibromobenzene and trimellitic acid are used in a mass ratio of 1:1.

[0123] The room temperature (25°C) lithium-ion conductivity of the solid electrolyte membrane in this example was measured to be 0.6 mS / cm using the test method described in Example 1. -1 .

[0124] Example 10

[0125] This example provides a solid-state battery, comprising a lithium iron phosphate cathode, a lithium metal anode, and the solid electrolyte membrane described in Example 1. After 200 cycles at a current of 0.5C and a temperature of 25°C, the capacity is 116.8 mAh / g, with a capacity retention of 91.7%, as shown in Figure 7.

[0126] Comparative Example 1

[0127] The only difference between the preparation method of the solid electrolyte membrane in this example and that in Example 1 is that only pyromellitic acid is used in step (1) of this example. The solid electrolyte membrane prepared in this example has a two-dimensional layered structure, with only two-dimensional ion transport channels in the horizontal direction, and no continuous translayer ion channels in the vertical direction, that is, no in-plane sieve structure.

[0128] The solid electrolyte membrane prepared in this example was sandwiched between two stainless steel sheets to test its AC impedance. The specific test results are shown in Figure 8. Then, the lithium-ion conductivity was calculated, and the room temperature (25℃) lithium-ion conductivity of the solid electrolyte membrane in this example was found to be 0.01 mS / cm. -1 .

[0129] In summary, this invention, through screening the raw materials for preparing layered materials, designed a layered material with an in-plane sieve structure, creating longitudinal ion channels within the layers, and further constructing a solid electrolyte membrane. This layered solid electrolyte membrane has two-dimensional ion channels in the horizontal direction and native continuous translayer ion channels in the vertical direction, achieving extremely high ionic conductivity, up to 10 mS / cm. -1 .

[0130] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A solid state electrolyte membrane, characterized by: The invention comprises a layered material and an electrolyte salt, wherein the electrolyte salt is loaded on the layered material; the layered material has at least two organic molecular layers; the organic molecular layers are porous and are assembled from small molecules by at least one selected from hydrogen bonds, covalent bonds, and intermolecular forces; the small molecules are selected from at least one selected from aromatic compounds, compounds containing triazine rings, and compounds containing amide groups.

2. The solid-state electrolyte film of claim 1, wherein: The pore size of the organic molecular layer is 0.3–1 nm; and / or the hole density of the organic molecule layer is 2 x 10 5 ~ 5 x 10 6 cm-1 2 ; And / or, the distance between two adjacent organic molecular layers in the layered material is 0.1 to 1 nm.

3. The solid-state electrolyte film of claim 1, wherein: The small molecule is selected from at least two of the following: trimellitic acid, pyrogallol, aniline, 1,3,5-trinitrobenzene, 1,3,5-trichloro-2,4,6-trinitrobenzene, phenol, benzenesulfonic acid, p-dibromobenzene, 2,7-bis(bromomethyl)naphthalene, 1-amino-5-naphthol, 1,5-naphthalenedisulfonic acid, 1,3,6-trichloronaphthalene, 1,3,5-trichlorobenzene, melamine, melamine, uric acid, cyanuric acid, urea, and thiourea.

4. The solid-state electrolyte film of claim 1, wherein: The small molecules include compound A and compound B; The compound A is selected from at least one of melamine, melamine, and p-dibromobenzene; The compound B is selected from at least one of pyromellitic acid, 1,3,5-trichloro-2,4,6-trinitrobenzene, trimellitic acid, and urea.

5. The solid-state electrolyte film of claim 4, wherein: The mass ratio of compound A to compound B is (0.3–4):

1.

6. The solid-state electrolyte film of claim 1, wherein: The mass of the layered material is 70-90% of the mass of the solid electrolyte membrane.

7. The solid-state electrolyte film of claim 1, wherein: The mass ratio of the layered material to the electrolyte salt is 1:(0.1-1.5); And / or, the solid electrolyte membrane further includes a binder; the mass ratio of the layered material to the binder is 1:(0.01 to 0.3).

8. The solid-state electrolyte film of claim 1, wherein: The electrolyte salt is selected from at least one of lithium chloride, lithium bromide, lithium hexafluorophosphate, lithium nitrate, lithium perchlorate, lithium bis(trifluoromethylsulfonyl)imide, lithium bis(fluorosulfonyl)imide, lithium fluoroalkyl phosphate, lithium dioxolane borate, lithium difluorooxolane borate, and lithium tetrafluoroborate. Alternatively, the electrolyte salt is selected from at least one of sodium chloride, sodium bromide, sodium hexafluorophosphate, sodium nitrate, sodium perchlorate, sodium bis(trifluoromethylsulfonyl)imide, sodium bis(fluorosulfonyl)imide, sodium fluoroalkyl phosphate, sodium dioxolane borate, sodium difluorooxolane borate, and sodium tetrafluoroborate. Alternatively, the electrolyte salt is selected from at least one of potassium chloride, potassium bromide, potassium hexafluorophosphate, potassium nitrate, potassium perchlorate, potassium bis(trifluoromethylsulfonyl)imide, potassium bis(fluorosulfonyl)imide, potassium fluoroalkyl phosphate, potassium dioxalate borate, potassium difluorooxalate borate, and potassium tetrafluoroborate.

9. The solid-state electrolyte film according to any one of claims 1 to 8, characterized by: The thickness of the solid electrolyte membrane is 50–1000 μm; and / or the solid-state electrolyte film has an ion conductivity of 0.5-10 mS cm measured at 25 -1 .

10. The method of producing a solid-state electrolyte film according to any one of claims 1 to 9, characterized by: Includes the following steps: S1: Mix and grind the raw materials, including small molecules, to obtain the layered material; S2: Mix the raw materials including the layered material, electrolyte salt, and optionally added binder, and then form a film to obtain the solid electrolyte membrane.

11. The method of claim 10, wherein: Step S1 is as follows: the raw material, which includes small molecules and lubricating solvent, is ball-milled and then dried to obtain the layered material.

12. The method of claim 11, wherein: The lubricating solvent includes at least one of water, DMSO; And / or, the mass ratio of the small molecule and the lubricating solvent is 1:(0.5-1.5).

13. A solid state battery, characterized by: The solid-state electrolyte film according to any one of claims 1-9.

14. Use of the solid-state electrolyte film according to any one of claims 1-9 and / or the solid-state battery according to claim 13 in electronic devices.

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