Solid-state oxide electrolyte and preparation method thereof, solid-state electrolyte membrane and solid-state battery

Abstract

The invention relates to the technical field of energy storage batteries, in particular to a solid-state oxide electrolyte and a preparation method thereof, a solid-state electrolyte membrane and a solid-state battery. The solid oxide electrolyte comprises an oxide electrolyte matrix and an anionic dopant; the oxide electrolyte matrix comprises at least one of a lithium system matrix, a sodium system matrix and a potassium system; the anionic dopant correspondingly comprises at least one of a lithium system additive, a sodium system additive and a potassium system additive. According to the solid oxide electrolyte based on transferable anion doping and the all-solid-state lithium metal battery provided by the invention, controllable migration of anions in the electrolyte is regulated and controlled, a dynamic self-adaptive interface layer (DAIs) is constructed, and long-cycle stable work under low external pressure is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of energy storage batteries, in particular to a solid-state oxide electrolyte, a preparation method thereof, a solid-state electrolyte film and a solid-state battery. BACKGROUND

[0002] All-solid-state lithium metal batteries (ASSLMBs) are significantly superior to traditional lithium-ion batteries (LIBs) in safety and energy density due to the use of non-flammable solid-state electrolytes and high-theoretical-capacity lithium metal (Li, 3860mAh·g -1 ) anodes. Among them, solid-state oxide electrolytes (such as garnet-type LLZO (Li7La3Zr2O 12 ), NASICON-type LATP (Li 1.07 Al 0.07 Ti 1.93 (PO4)3) are the key material choices for ASSLMBs due to their high chemical stability and humidity resistance.

[0003] However, there are two major bottlenecks in the practical application of solid-state oxide electrolytes:

[0004] 1. Interface contact failure: The modulus of oxide electrolytes is extremely high (LLZO ≈ 200 GPa), and initial voids are easily formed when assembled with Li anodes due to surface defects; the volume change (expansion rate > 100%) of Li stripping / deposition during cycling will further expand the voids, leading to continuous deterioration of solid-solid contact and a sharp rise in interface resistance;

[0005] 2. High external pressure dependence: Existing ASSLMBs require an external stacking pressure of > 5 MPa to maintain interface contact, and the cycle life under low external pressure (< 1 MPa) is usually < 1000 times, which is much lower than that of LIBs (> 3000 times);

[0006] 3. Static interface modification is ineffective: Traditional solutions (such as pre-deposition of LiF layer and introduction of metal interlayer) are “static modifications” that cannot dynamically respond to Li anode volume changes, and will still lead to interface degradation due to void expansion after long-term cycling. SUMMARY

[0007] The purpose of the present application is to overcome the deficiencies and shortcomings of the prior art, and to provide a solid-state oxide electrolyte, a preparation method thereof, a solid-state electrolyte film and a solid-state battery.

[0008] In order to achieve the above-mentioned purpose, the following solutions are adopted in the present application:

[0009] A solid oxide electrolyte comprising an oxide electrolyte matrix and an anion dopant; the oxide electrolyte matrix comprising at least one of a lithium-based matrix, a sodium-based matrix, and a potassium-based matrix; the anion dopant corresponding to at least one of a lithium-based additive, a sodium-based additive, and a potassium-based additive.

[0010] The lithium-based matrix comprises a garnet-type lithium-based matrix or a NASICON-type lithium-based matrix;

[0011] Preferably, the garnet-type lithium-based matrix comprises Li7La3Zr2O 12 , or Li 6.4 La3Zr 1.4 Ta 0.6 O 12 ;

[0012] The NASICON-type lithium-based matrix comprises Li 1.07 Al 0.07 Ti 1.93 (PO4)3, or Li 1.5 Al 0.5 Ge 1.5 (PO4)3;

[0013] Preferably, the lithium-based additive comprises at least one of LiF, LiCl, LiBr, LiI.

[0014] The sodium-based matrix comprises a NASICON-type sodium-based matrix or a NASICON-type sodium-based matrix;

[0015] Preferably, the NASICON-type sodium-based matrix comprises Na3Zr2Si2PO 12 ;

[0016] Preferably, the NASICON-type sodium-based matrix comprises Na7La3Zr2O 12 ;

[0017] Preferably, the sodium-based additive comprises at least one of NaF, NaCl.

[0018] The potassium-based matrix comprises a garnet-type potassium-based matrix or a NASICON-type potassium-based matrix;

[0019] Preferably, the garnet-type potassium-based matrix comprises K7La3Zr2O 12 ;

[0020] Preferably, the NASICON-type potassium-based matrix comprises K 1.5 Al 0.5 Ge 1.5 (PO4)3;

[0021] Preferably, the sodium system additive comprises at least one of KF or KCl.

[0022] The molar ratio of the anion dopant is 0.02-1%, preferably 0.05%-0.5%.

[0023] The ratio of the anion of the anion dopant to the metal cation migration energy barrier is 0.5-1.5.

[0024] The application also includes a preparation method of the solid-state oxide electrolyte, comprising the following steps:

[0025] (1) batching and ball milling: ball milling the oxide electrolyte matrix powder and the anion dopant in an inert gas atmosphere; preferably, the ball-to-material ratio is 10:1, ball milling at a speed of 500-600 rpm for 12-15 h to obtain a uniformly mixed powder;

[0026] (2) forming and sintering: a. cold pressing: loading the mixed powder into a mold and cold pressing at a pressure of 300-400 MPa to form a green body; b. atmosphere sintering: sintering in an oxygen atmosphere according to the following parameters; preferably, the temperature rising rate is controlled at 25℃ / min: for the garnet-type matrix, the sintering temperature is 1100-1200℃, and the holding time is 6-8 h; for the NASICON-type matrix, the sintering temperature is 800-900℃, and the holding time is 4-6 h.

[0027] The application also includes a solid-state electrolyte film obtained by cold pressing the solid-state oxide electrolyte into a film; preferably, the solid-state electrolyte film has a thickness of 1-2 mm, a relative density of >95%, and a porosity of <5%.

[0028] The application also includes a solid-state battery comprising the solid-state electrolyte film, a negative electrode, and a positive electrode.

[0029] Preferably, the negative electrode is a Li foil, a Na foil, or a K foil.

[0030] Preferably, the active material of the positive electrode is a lithium system, such as LiCoO2, NCM, or LTO; a sodium system, such as Na3V2(PO4)3; or a potassium system, such as K2Fe[Fe(CN)6].

[0031] During the cycle process, a dynamic self-adaptive interface layer containing a halogen-rich phase is formed in situ at the interface between the solid-state electrolyte film and the negative electrode, and the self-adaptive interface layer can continuously fill the interface gap under the low external pressure of 0.1-1 MPa.

[0032] Compared with the prior art, the application has the following advantages:

[0033] This invention provides a solid oxide electrolyte and an all-solid-state lithium metal battery based on a migratable anion-doped electrolyte. By controlling the controllable migration of anions in the electrolyte, a dynamic adaptive interface layer (DAIs) is constructed to achieve stable long-cycle operation under low external pressure.

[0034] The aforementioned Dynamic Adaptive Interface Layers (DAIs) refer to the migratable anions (F...) pre-implanted in the solid oxide electrolyte during electrochemical cycling. - / Cl - / Br - / I - Driven by an electric field / concentration gradient, it migrates directionally to the interface between the metal anode (Li / Na / K) and the solid electrolyte, and combines with metal cations to form a multiphase functional layer. This layer is 3-8 μm thick and contains an anion-rich metal salt phase (such as LiF, NaCl) and a transition phase that connects with the electrolyte / anode. It has self-limiting growth (thickness increase during cycling <5%) and stress regulation capabilities, and can dynamically fill the gaps caused by changes in the anode volume. It can maintain a tight solid / solid contact under low external stacking pressure of 0.1-1.0 MPa.

[0035] Meanwhile, the doped anions migrate in the oxide lattice via interstitial diffusion, and their migration energy barrier is similar to that of the metal cations (Li). + / Na + / K + The migration barrier ratio is 0.5 to 1.5 to ensure synchronization with cation migration and avoid interfacial ion accumulation or void generation caused by migration alone.

[0036] This invention utilizes a solid oxide electrolyte modified with migratable anion doping, and an all-solid-state lithium / sodium / potassium metal battery assembled using this electrolyte. It is particularly suitable for high-energy-density energy storage scenarios that operate stably under low external stacking pressure (0.1-1 MPa), such as power batteries for new energy vehicles and large-scale energy storage power stations. It can also be extended to alkali metal battery systems. Attached Figure Description

[0037] Figure 1 Schematic diagram of DAI formation mechanism:

[0038] Figure 2 Comparison of X-ray diffraction patterns of undoped and solid electrolytes from Example 1;

[0039] Figure 3 Example 1: Scanning electron microscope cross-sectional image of the negative electrode-electrolyte interface after cycling;

[0040] Figure 4 Comparison of long-cycle capacity retention between undoped and all-solid-state batteries at room temperature in Example 1;

[0041] Figure 5 : Curves showing the change in interface resistance over time during cycling at room temperature for undoped samples and in Example 1. Detailed Implementation

[0042] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0043] Test Standards

[0044] Environmental conditions: Temperature (-20℃±2℃, 25℃±2℃, 60℃±2℃), humidity (<0.1ppm), argon protection;

[0045] Electrochemical testing: Constant current charge-discharge (current density 0.1–2.0 mA·cm⁻¹) -2 Voltage range 3.0–4.2V (LiCoO2 / NCM), 1.0–2.5V (LTO), 2.5–3.8V (Na3V2(PO4)3);

[0046] Long-term stability: Impedance and capacitance are tested every 100 cycles, and data are recorded for 2000 cycles;

[0047] Safety test: Cyclic performance was tested after needle puncture (1mm diameter steel needle) and compression (0.5MPa) to verify interface stability.

[0048] Example 1: Performance of 0.5% LiF-doped LLZO electrolyte and lithium battery

[0049] 1. Preparation of oxide solid electrolytes:

[0050] a. Ingredients: 835.5g (0.998mol) of LLZO powder and 0.13g (0.005mol) of LiF powder, mole fraction 0.5%;

[0051] b. Ball milling: 5mm zirconia balls (1000g), ball milling at 550rpm for 14h in an argon atmosphere;

[0052] c. Sintering: The mixed powder is cold-pressed at 350MPa for 5 minutes to form a green body (12mm in diameter and 1.5mm in thickness); then sintered in an oxygen atmosphere at a temperature of 3℃ / min to 1150℃ and held for 7 hours.

[0053] 2. Preparation of solid electrolyte membrane: After sintering, the membrane was cold-pressed again at 360 MPa for 5 min to obtain an electrolyte sheet (relative density 96.2%, room temperature Li). + Electrical conductivity 2.1 mS·cm -1 ).

[0054] 3. Battery assembly and performance testing

[0055] a. Assembly: Li-B alloy anode (60wt% Li), 0.5% LiF-LLZO solid electrolyte membrane, LiCoO2 cathode (area capacity 1.5 mAh·cm³). -2 The initial external pressure is 0.6 MPa, and it is packaged as a CR2032 button cell.

[0056] b. Test: 1.25 mA·cm at 25℃ -2 Cycling, initial capacity 135 mAh·g -1 The retention rate was 88% after 2000 cycles. After the cycle, the sample was disassembled and cross-sectional SEM was performed. No penetrating dendrites were observed, and the interface was found to be denser.

[0057] To verify the effect of different anionic dopant concentrations, different dopant concentrations were tested, as shown in Table 1.

[0058] Table 1

[0059]

[0060]

[0061] The results show that when the concentration is below 0.05%, the anion migration is insufficient, and when it is above 0.5%, lattice distortion leads to a decrease in ionic conductivity of >20%. Figure 1 A schematic diagram of the DAI formation mechanism is shown: (a) Initial state: Lithium metal (anode) is in close contact with the solid electrolyte (SSE). (b) Discharge / stripping (undoped): Pitfalls (voids) appear on the lithium metal side, the electrolyte cannot deform, and the contact point breaks. (c) Anion migration (in this invention): F- or Cl- ions move from the inside of the electrolyte to the interface (arrows point to the anode). (d) DAI formation and repair: A new gray layer (DAI layer) is formed at the interface, filling the pits in (b) and re-establishing the connection. Figure caption: 10-metal anode, 20-oxide electrolyte, 21-doped anion, 30-interface void, 40-dynamically adaptive interface layer (DAI);

[0062] To verify the stability and self-limiting growth of DAI, a comparison was made between a pre-deposited LiF layer (a static interface layer, obtained by physical vapor deposition or magnetron sputtering of a thin LiF layer on the electrolyte sheet surface; the thickness was 2 μm in this comparative example) and 0.5% LiF-doped DAI. The results are shown in Table 2 (25℃, 0.6 MPa, 1.25 mA·cm). -2 As shown in Table 3, the current density dependence of 0.5% LiF-doped DAI self-limited growth was also tested.

[0063] Table 2

[0064]

[0065] Table 3

[0066]

[0067] The results show that as the current density increases, the migration rate of anions accelerates, but Li + The binding rate with anions increases synchronously, and when the two reach equilibrium, the thickness of DAI no longer increases.

[0068] Verification of interfacial stress and microstructure

[0069] 1. Quantification of interfacial stress (Raman spectroscopy and 532nm laser testing) a. Undoped LLZO cell (Comparative Example 1): Interfacial stress peak 120MPa, locally concentrated (cracks visible in SEM cross-section); b. 0.5% LiF-LLZO cell: Stress uniformly distributed, peak <40MPa (no cracks observed in SEM cross-section); c. Conclusion: The transition phase of DAI (such as the LiF-LLZO transition layer) can disperse local stress and avoid interfacial failure. Figure 2 The X-ray diffraction patterns of the undoped and Example 1 (0.5% LiF doped) solid electrolytes are shown in comparison. Figure 3 A scanning electron microscope cross-sectional image of the negative electrode-electrolyte interface after cycling is shown for Example 1 (0.5% LiF doping);

[0070] 2. Low-temperature performance verification (-20℃, 0.3MPa, 0.5mA·cm) -1 a. 0.5% LiF-LLZO battery: initial capacity 120mAh·g -1 a. 68% retention rate after 1000 cycles; b. Undoped LLZO battery: initial capacity 95 mAh·g -1 c. Reason: The LiF-rich phase of DAI retains a certain ionic conductivity (0.1 mS·cm) even at low temperatures. -1 This helps to prevent the interface resistance from spike. Figure 4 The comparison shows the long-cycle capacity retention of the undoped (Comparative Example 1) and Example 1 (0.5% LiF doped) all-solid-state batteries at room temperature; Figure 5 The curves showing the change of interface resistance over time during cycling at room temperature are shown for the undoped (Comparative Example 1) and Example 1.

[0071] Example 2: Performance of 0.2% LiCl-doped LATP electrolyte and lithium battery

[0072] 1. Preparation of oxide solid electrolytes:

[0073] a. Ingredients: Take 385.8g of LATP powder (0.998mol, particle size 1μm) and 0.085g of LiCl powder (0.002mol, particle size 30-50nm), and mix them at a molar fraction of 0.2%;

[0074] b. Ball milling: Add 1000g of 5mm diameter zirconia balls (ball-to-material ratio 10:1) and ball mill at 500rpm for 15h under argon atmosphere to obtain a uniformly mixed powder;

[0075] c. Sintering and forming: The mixed powder is cold-pressed at 300MPa for 5min to form a green body (10mm in diameter and 1mm in thickness); and sintered in an oxygen atmosphere at 2℃ / min to 850℃ and held for 5h.

[0076] 2. Preparation of solid electrolyte membrane: After sintering, the membrane was cold-pressed again at 360 MPa for 5 min to obtain an electrolyte sheet (relative density 95.5%, room temperature Li). + Electrical conductivity 1.7 mS·cm -1 ).

[0077] 3. Battery assembly and performance testing

[0078] Assembly: Following the sequence: Li foil anode (50 μm thickness) → 0.2% LiCl-LATP solid electrolyte membrane → LTO cathode (area capacity 2.1 mAh·cm³). -2 The positive electrode composite layer consists of LTO (0.2% LiCl-LATP solid electrolyte powder) and Super P mixed in a mass ratio of 7:2:1, with an optional addition of approximately 2wt% PTFE as a binder. The layers are stacked sequentially, an initial external pressure of 0.3 MPa is applied, and the cells are packaged as CR2032 button cells.

[0079] Performance testing: Tests were conducted at -20℃, 25℃, and 60℃ at a current of 0.5–1.0 mA·cm⁻¹. -2 The current density cycling results are shown in Table 4 below:

[0080] Table 4

[0081]

[0082] Example 3: 0.5% NaF-doped Na3Zr2Si2PO 12 Sodium batteries

[0083] 1. Preparation of oxide solid electrolytes

[0084] a. Ingredients: Take Na3Zr2Si2PO 12528.0 g of powder (0.995 mol, particle size 2 μm) and 0.21 g of NaF powder (0.005 mol, particle size 30-50 nm) were mixed at a molar fraction of 0.5%.

[0085] b. Ball milling: Add 1000g of 5mm diameter zirconia balls (ball-to-material ratio 10:1) and ball mill at 550rpm for 14h under argon atmosphere to obtain a uniformly mixed powder;

[0086] c. Sintering and forming: The mixed powder was cold-pressed at 350MPa for 5 minutes to form a green body (12mm in diameter and 1.5mm in thickness); and sintered in an oxygen atmosphere at a rate of 3℃ / min to 900℃ and held for 6 hours.

[0087] 2. Preparation of oxide solid electrolyte membrane: After sintering, it was cold-pressed twice at 360 MPa for 5 min to obtain electrolyte sheet (relative density 95.8%, room temperature Na). + Electrical conductivity 0.9 mS·cm -1 ).

[0088] 3. Battery assembly and performance testing:

[0089] Assembly: Follow the sequence "Na foil negative electrode (100μm thickness) → 0.5% NaF-Na3Zr2Si2PO" 12 Solid electrolyte membrane → Na3V2(PO4)3 positive electrode (area capacity 1.2 mAh·cm³) -2 The following components were stacked in sequence: Na3V2(PO4)3:electrolyte:Super P = 7:2:1, and an initial external pressure of 0.5 MPa was applied. The resulting product was then packaged as a CR2032 button cell.

[0090] Performance testing: at 25℃ with 0.8 mA·cm -2 Current density cycling, initial discharge capacity 110 mAh·g -1 After 1500 cycles, the capacity retention was 75%, SEM characterization showed no Na dendrite formation, and the interfacial resistance remained stable at 220–250 Ω·cm. 2 .

[0091] Comparative Example 1: Set up in accordance with Example 1, without LLZO electrolyte and lithium battery performance.

[0092] Solid electrolyte preparation: 839.7 g (1.0 mol, particle size 1–3 μm) of LLZO powder was used, without LiF doping; the ball milling, sintering, and molding processes were exactly the same as in Example 1 to obtain an electrolyte membrane (room temperature LiF). + Electrical conductivity 2.3 mS·cm -1 );

[0093] Battery assembly and performance: The battery structure is consistent with that of Example 1, and the battery operates at 1.25 mA·cm at 25°C. -2 After 500 cycles, the capacity retention was less than 40%, and the interface resistance soared to 850 Ω·cm. 2 SEM revealed 1.5–2 μm voids and lithium dendrites at the interface.

[0094] Comparative Example 2: Set up in accordance with Example 2, without LATP electrolyte and lithium battery performance.

[0095] Electrolyte preparation: Only 386.6 g (1.0 mol, particle size 1 μm) of LATP powder was used, without LiCl doping; the ball milling, sintering, and molding processes were exactly the same as in Example 2 to obtain an electrolyte membrane (room temperature LiCl). + Electrical conductivity 1.9 mS·cm -1 );

[0096] Battery assembly and performance: The battery structure is consistent with that of Example 2, and the battery is installed at 1.0 mA·cm at 25°C. -2 After 500 cycles, the capacity retention was 38%, and the interface resistance soared to 920 Ω·cm. 2 It will fail after 100 cycles at low temperature (-20℃).

[0097] Comparative Example 3: Performance of non-lithium-doped (NaF-doped LLZO) electrolyte and lithium battery, corresponding to Example 1.

[0098] Electrolyte preparation: 835.5 g (0.995 mol) of LLZO powder and 0.21 g (0.005 mol) of NaF powder were mixed at a molar fraction of 0.5%; the ball milling, sintering, and molding processes were the same as in Example 1 to obtain electrolyte sheets (room temperature Li). + Electrical conductivity 1.5 mS·cm -1 );

[0099] Battery assembly and performance: The battery structure is consistent with that of Example 1, and the battery operates at 1.25 mA·cm at 25°C. -2 After 500 cycles, the capacity retention was 45%, and the interface resistance was 620 Ω·cm. 2 Na + Blocking Li + Migration path issues lead to significant performance degradation.

[0100] Comparative Example 4: Performance of the overdoped (2.5% LiF-doped LLZO) electrolyte and lithium battery, corresponding to Example 1.

[0101] Electrolyte preparation: 831.3 g (0.990 mol) of LLZO powder and 0.65 g (0.025 mol) of LiF powder were mixed at a molar fraction of 2.5%; the ball milling, sintering, and molding processes were the same as in Example 1 to obtain electrolyte sheets (room temperature LiF). + Electrical conductivity 1.3 mS·cm -1 (Lattice distortion rate 2.5%);

[0102] Battery assembly and performance: The battery structure is consistent with that of Example 5, and the battery operates at 1.25 mA·cm at 25°C. -2 After 500 cycles, the capacity retention was 58%, the peak interfacial stress was 92 MPa, and microcracks appeared in the electrolyte. Table 5 shows a comparison of the performance of the lithium-based electrolyte and battery; Table 6 shows a comparison of the performance of the sodium-based electrolyte and battery.

[0103] Table 5

[0104]

[0105]

[0106] Table 6

[0107]

[0108] Key conclusions

[0109] 1. Necessity of doping: Although the undoped systems (Comparative Examples 1, 2, and 5) have slightly higher initial conductivity, due to the lack of dynamic adaptive interfaces (DAIs), interface voids and dendrites are rapidly generated during cycling, and the capacity retention rate is <50% after 500 cycles. In contrast, the doped systems of this invention (Examples 1-3) have a capacity retention rate of ≥75% after 2000 cycles, proving that mobile anion doping is the core of achieving long cycling under low external pressure.

[0110] 2. Justification of doping: Non-lithium-based doping (Comparative Example 3) introduces heterogeneous cations (Na). + Blocking Li + Migration path, Li + Electrical conductivity from 2.3 mS·cm -1 Reduced to 1.5 mS·cm -1 (Reduction > 30%); Excessive doping (Comparative Example 4) leads to lattice distortion.

[0111] 3. Wide temperature range and safety advantages: Examples 1 to 3 maintain stable performance in the range of -20℃ to 60℃, while the undoped system fails rapidly at low temperatures; and the capacity retention rate of the doped system after needle penetration is ≥70%, while the undoped system fails directly, verifying high safety.

[0112] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. It will be apparent to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention.

[0113] Therefore, the embodiments should be regarded as exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of the equivalents of the claims be included within the invention.

[0114] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A solid oxide electrolyte, characterized in that, It includes an oxide electrolyte matrix and an anion dopant; the oxide electrolyte matrix includes at least one of a lithium system matrix, a sodium system matrix, and a potassium system matrix; the anion dopant includes at least one of a lithium system additive, a sodium system additive, and a potassium system additive.

2. The solid oxide electrolyte according to claim 1, characterized in that, The lithium system matrix includes a garnet-type lithium matrix or a NASICON-type lithium matrix; Preferably, the garnet-type lithium matrix comprises Li7La3Zr2O 12 、or Li 6.4 La3Zr 1.4 Ta 0.6 O 12 ; The aforementioned NASICON-type lithium matrix includes Li 1.07 Al 0.07 Ti 1.93 (PO4)3, or Li 1.5 Al 0.5 Ge 1.5 (PO4)3; Preferably, the lithium system additive includes at least one of LiF, LiCl, LiBr, and LiI.

3. The solid oxide electrolyte according to claim 1, characterized in that, The sodium system matrix includes a NASICON-type sodium matrix or a NASICON-type sodium matrix; Preferably, the NASICON-type sodium matrix includes Na3Zr2Si2PO4. 12 ; Preferably, the NASICON-type sodium matrix includes Na7La3Zr2O 12 ; Preferably, the sodium system additive includes at least one of NaF and NaCl.

4. The solid oxide electrolyte according to claim 1, characterized in that, The potassium system matrix includes a garnet-type potassium matrix or a NASICON-type potassium matrix; Preferably, the garnet-type potassium matrix includes K7La3Zr2O 12 ; Preferably, the NASICON-type potassium matrix includes K 1.5 Al 0.5 Ge 1.5 (PO4)3; Preferably, the sodium system additive includes at least one of KF or KCl.

5. The solid oxide electrolyte according to claim 1, characterized in that, The molar percentage of the anionic dopant is 0.02% to 1%; preferably 0.05% to 0.5%.

6. The solid oxide electrolyte according to claim 1, characterized in that, The ratio of the migration barrier between the anion and the metal cation of the anionic dopant is 0.5 to 1.

5.

7. A method for preparing the solid oxide electrolytic membrane described above, characterized in that, Includes the following steps: (1) Batching and ball milling: In an inert gas atmosphere, the oxide electrolyte matrix powder and the anion dopant are ball milled; preferably, the ball-to-material ratio is 10:1, and the mixture is ball milled at 500-600 rpm for 12-15 hours to obtain a uniformly mixed powder. (2) Molding and sintering: a. Cold pressing: The mixed powder is loaded into a mold and cold pressed under a pressure of 300-400 MPa to form a green body; b. Atmosphere sintering: Sintering is carried out in an oxygen atmosphere according to the following parameters; preferably, the heating rate is controlled at 25℃ / min: Garnet type matrix: sintering temperature 1100-1200℃, holding time 6-8h; NASICON type matrix: sintering temperature 800-900℃, holding time 4-6h.

8. A solid electrolyte membrane, characterized in that, The solid electrolyte film is obtained by cold pressing the solid oxide electrolyte as described in any one of claims 1-6; preferably, the solid electrolyte film has a thickness of 1-2 mm, a relative density >95%, and a porosity <5%.

9. A solid-state battery, characterized in that, Includes the solid electrolyte membrane, negative electrode, and positive electrode as described in claim 8. Preferably, the negative electrode is a Li foil, a Na foil, or a K foil; Preferably, the active material of the positive electrode is a lithium system of LiCoO2, NCM, or LTO, a sodium system of Na3V2(PO4)3, or a potassium system of K2Fe[Fe(CN)6].

10. The solid-state battery according to claim 9, characterized in that, During the cycling process, a dynamic adaptive interface layer containing a halogen-enriched phase is formed in situ at the interface between the solid electrolyte membrane and the negative electrode. The adaptive interface layer can continuously fill the interface voids under the low external pressure conditions of 0.1 to 1 MPa.

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