Low-temperature oxidation-dynamic sintering nanometer LATP preparation method
By employing a low-temperature oxidation-dynamic sintering method to prepare nano-LATP, and using boron-containing glass phase and lanthanide element dopants for modification, combined with segmented low-temperature oxidation and dynamic sintering processes, the problems of grain coarsening and impurity phase formation caused by high-temperature sintering were solved, and high ionic conductivity and structural stability of nanocrystalline LATP were achieved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ZHEJIANG DONGTAI NEW MATERIALS CO LTD
- Filing Date
- 2026-02-11
- Publication Date
- 2026-05-08
AI Technical Summary
In existing methods for preparing LATP materials, high-temperature sintering leads to grain coarsening, grain boundary defects, and the formation of impurity phases, which affect ionic conductivity and structural stability.
A low-temperature oxidation-dynamic sintering method was adopted to prepare nanocrystalline LATP solid electrolyte. This method involves composite modification with boron-containing glass phase forming agent and lanthanide element dopant, combined with segmented low-temperature oxidation and dynamic sintering processes, and using spark plasma sintering and strong magnetic field assistance.
This method achieves uniformity and high density in nanocrystalline structures, significantly improves ionic conductivity and structural stability, and reduces energy consumption and production cycle.
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Figure CN122000481A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of materials technology, specifically relating to a method for preparing nano-LATP through low-temperature oxidation-dynamic sintering. Background Technology
[0002] Solid-state electrolytes are the core components of next-generation high-safety, high-energy-density all-solid-state lithium batteries. Among them, lithium aluminum titanium phosphate (LATP) materials based on the NASICON structure have attracted much attention due to their high room-temperature ionic conductivity, excellent air stability, and wide electrochemical window. Currently, the preparation of LATP materials mainly relies on high-temperature solid-state reaction methods, which involve mechanically mixing precursors such as lithium, aluminum, titanium, and phosphorus sources, followed by long-term sintering at high temperatures (usually above 900°C) to complete the solid-state diffusion reaction and obtain a dense ceramic body. In addition, wet chemical methods such as sol-gel and co-precipitation methods have also been used to improve the uniformity of precursors, but they still ultimately require a high-temperature sintering step to achieve material crystallization and densification.
[0003] However, the existing preparation methods described above, with their high-temperature and long-duration sintering processes, easily lead to abnormal coarsening of LATP grains, forming micron-sized or even larger grains. This not only reduces the effective ion transport interface but may also introduce more grain boundary defects. Secondly, the high-temperature environment exacerbates the reduction tendency of titanium, easily generating impurity phases such as low-valence titanium oxides, which disrupts the uniformity and stability of the crystal structure and impairs ionic conductivity. Summary of the Invention
[0004] The purpose of this invention is to provide a low-temperature oxidation-dynamic sintering method for preparing nano-LATP, so as to solve the problems mentioned in the background art.
[0005] To achieve the above objectives, the present invention provides the following technical solution:
[0006] A method for preparing nano-LATP through low-temperature oxidation-dynamic sintering includes the following steps:
[0007] S1. Mix lithium source, aluminum source, titanium source and phosphorus source according to LATP stoichiometric ratio, and add at least one of boron glass phase forming agent or lanthanide doping modifier to prepare modified precursor mixture.
[0008] S2. The modified precursor mixture is subjected to segmented low-temperature oxidation heat treatment in an oxygen-containing atmosphere to obtain pre-oxidized powder;
[0009] S3. The pre-oxidized powder is subjected to dynamic sintering treatment to obtain modified nanocrystalline LATP solid electrolyte material.
[0010] Preferably, the boron-containing glass phase forming agent is at least one of boric acid, boron oxide, and lithium borate, and its addition amount is 0.1-5 wt.% of the theoretical mass fraction of LATP.
[0011] Preferably, the lanthanide-containing doping modifier is at least one of lanthanum oxide, cerium oxide, and yttrium oxide, and its addition amount is to replace 0.1-5 at.% of Ti sites in LATP.
[0012] Preferably, in step S1, the boron-containing glass phase forming agent is added by first dissolving the boron-containing glass phase forming agent in an organic solvent to form a solution, and then uniformly mixing it with the mixture of the lithium source, aluminum source, titanium source, and phosphorus source.
[0013] Preferably, the segmented low-temperature oxidation heat treatment in step S2 specifically includes:
[0014] First stage: Keep warm at 300℃~450℃ for 1~5 hours;
[0015] The second stage involves holding the temperature at 500℃ to 650℃ for 2 to 8 hours, during which a gaseous precursor containing lanthanide elements is introduced as a dopant for gas-phase assisted doping.
[0016] Preferably, the gaseous precursor is at least one of lanthanide acetylacetonates, cyclopentadienyl compounds, or halides.
[0017] Preferably, the dynamic sintering treatment in step S3 adopts spark plasma sintering, with the following process parameters: sintering temperature of 700℃~900℃, sintering pressure of 30~100MPa, holding time of 5~30 minutes, and a strong magnetic field of 0.1-10T is applied simultaneously with a pulsed current during the sintering process.
[0018] Preferably, the direction of the strong magnetic field is perpendicular to or at a specific angle to the direction of the pulse current, and the magnetic field strength is 1-5T.
[0019] Preferably, in step S3, 0.01-2 wt.% of two-dimensional nanomaterials are added to the pre-oxidized powder as grain boundary reinforcing agents before dynamic sintering. The two-dimensional nanomaterials include, but are not limited to, hexagonal boron nitride nanosheets, transition metal carbonitrides MXene, or graphene nanosheets.
[0020] Compared with the prior art, the beneficial effects of the present invention are:
[0021] (1) By introducing a composite modified material system of boron-containing glass phase forming agent and lanthanide element dopant, and combining it with a unique low-temperature oxidation pretreatment and dynamic sintering process, a multi-faceted synergistic enhancement effect was achieved. Under conditions significantly lower than the traditional sintering temperature, LATP solid electrolyte material with uniform nanocrystalline structure, extremely high density and extremely low grain boundary resistance was prepared. The ion transport characteristics of the bulk phase and interface were optimized by material modification, and abnormal grain growth and unfavorable phase transitions were suppressed by innovative process, thereby simultaneously improving the ionic conductivity and structural stability of the material.
[0022] (2) The low-temperature oxidation stage effectively removes organic impurities and completes the initial activation of the precursor, laying the foundation for subsequent rapid densification; while the dynamic sintering process realizes low-temperature, short-time, and high-densification sintering, which greatly reduces energy consumption and production cycle. Attached Figure Description
[0023] Figure 1 This is a flowchart of the present invention.
[0024] Figure 2 This is a SEM image of LATP, the product of Example 1.
[0025] Figure 3 The image shows the XRD pattern of LATP, a product from Example 1.
[0026] Figure 4 The image shows the EIS diagrams of the LATP product from Example 1 and the conventional LATP. Detailed Implementation
[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0028] Example 1:
[0029] Please see Figure 1-4 As shown, a method for preparing nano-LATP through low-temperature oxidation-dynamic sintering includes the following steps:
[0030] S1. Preparation of modified precursor mixture
[0031] According to stoichiometry, Li 1.3 Al 0.3 Ti 1.7(PO4)3 Weighing raw materials: Lithium carbonate (Li2CO3) as lithium source, aluminum isopropoxide (Al(OCH(CH3)2)3) as aluminum source, tetrabutyl titanate (Ti(OC4H9)4) as titanium source, and diammonium hydrogen phosphate ((NH4)2HPO4) as phosphorus source;
[0032] Weigh out 1.0 wt.% of boric acid (H3BO3) as a boron-containing glass phase forming agent, dissolve it in an appropriate amount of anhydrous ethanol, and stir until completely transparent;
[0033] Mix all the raw materials weighed in step 1, add the boric acid ethanol solution prepared in step 2, and ball mill at 300 rpm for 6 hours in a ball mill to achieve uniform mixing of each component at the molecular / atomic level in the liquid phase, forming a sol-like mixture.
[0034] The above mixture was dried at 80°C for 12 hours to obtain dried modified precursor powder.
[0035] S2. Segmented low-temperature oxidation heat treatment
[0036] The precursor powder obtained from S1 was evenly spread in an alumina crucible and placed in a tube furnace.
[0037] First stage of oxidation: The temperature is increased to 400℃ at a rate of 5℃ / min and kept in air for 3 hours to allow the organic matter to decompose completely.
[0038] Second-stage oxidation: The temperature continues to rise to 600℃ at a rate of 3℃ / min. When the temperature reaches 550℃, the gaseous precursor tris(2,2,6,6-tetramethyl-3,5-heptadecyl)yttrium (Y(TMHD)3) is introduced into the tube furnace reaction zone through a carrier gas (a mixture of argon and 5% oxygen) for gas-phase assisted doping. The target doping amount is to replace 2.0 at.% of Ti sites in LATP. This process continues until 600℃ and then is held at 600℃ for 5 hours to complete the initial crystallization and achieve uniform doping of yttrium, resulting in pre-oxidized powder. After the reaction is completed, the powder is cooled to room temperature with the furnace.
[0039] S3. Dynamic sintering treatment
[0040] 0.5 wt.% of hexagonal boron nitride (h-BN) nanosheets were added to the pre-oxidized powder obtained from S2 as a grain boundary reinforcing agent. The mixture was manually ground and mixed in an agate mortar for 10 minutes. The uniformly mixed powder was then loaded into a graphite mold and placed in a spark plasma sintering (SPS) furnace. The furnace was closed and a vacuum was applied to 10 °C. -2After Pa, high-purity argon gas was introduced as a protective atmosphere, and the SPS process parameters were set as follows: the temperature was increased to 800℃ at a rate of 100℃ / min, the axial pressure was 50MPa, and the holding time was 10 minutes. While applying pulsed current for sintering, the water-cooled electromagnet system was turned on, and a steady-state strong magnetic field with a direction perpendicular to the current direction and an intensity of 3T was applied. After the holding time was completed, the pressure and magnetic field were removed, and the material was rapidly cooled to room temperature in an argon atmosphere. After demolding, a dense, disc-shaped modified nanocrystalline LATP solid electrolyte material was obtained.
[0041] Example 2:
[0042] Please see Figure 1 As shown, a method for preparing nano-LATP through low-temperature oxidation-dynamic sintering includes the following steps:
[0043] S1. Preparation of modified precursor mixture
[0044] According to stoichiometry, Li 1˙3 Al 0˙3 Ti 1˙7 (PO4)3 raw materials: lithium acetate (CH3COOLi·2H2O) as lithium source, aluminum nitrate (Al(NO3)3·9H2O) as aluminum source, titanium dioxide (TiO2, anatase type, nanoscale) as titanium source, ammonium dihydrogen phosphate (NH4H2PO4) as phosphorus source, and boron oxide (B2O3) equivalent to 2.5 wt.% of the theoretical mass fraction of LATP as boron-containing glass phase forming agent.
[0045] All the above raw materials (including boron oxide) were dissolved / dispersed together in deionized water and stirred in a 70°C water bath to form a homogeneous suspension. Then, ammonia was slowly added dropwise to the solution as a precipitant until the pH reached 9.0, forming a coprecipitate. The coprecipitate was filtered, washed three times with deionized water and ethanol, dried at 100°C for 24 hours, and ground to obtain the modified precursor mixture powder.
[0046] S2. Segmented low-temperature oxidation heat treatment
[0047] The precursor powder obtained from S1 was uniformly mixed with cerium oxide (CeO2, nanoscale) powder. The amount of cerium oxide added was designed to replace 1.0 at.% of Ti sites in LATP. Doping was achieved through solid-phase mixing. The mixed powder was placed in a corundum crucible and then placed in a box furnace.
[0048] First stage oxidation: The temperature is increased to 350°C at a rate of 10°C / min and kept at this temperature in air for 2 hours to completely remove bound water and residual ammonia salts.
[0049] Second stage oxidation: Continue heating at a rate of 5℃ / min to 580℃, and keep at this temperature in air for 6 hours to allow the solid-phase reaction to proceed fully, complete doping and preliminary crystallization, and obtain pre-oxidized powder.
[0050] After the reaction is complete, allow it to cool naturally to room temperature.
[0051] S3. Dynamic sintering treatment
[0052] 0.1 wt.% of few-layer Ti3C2TxMXene nanosheets (obtained by HF etching of the Ti3AlC2MAX phase) were added to the pre-oxidized powder obtained in S2 as a grain boundary reinforcing agent. The mixture was dry-mixed in a planetary ball mill at 200 rpm for 1 hour. The mixed powder was then loaded into a graphite mold coated with boron nitride release agent. The mold was placed in a rapid hot pressing sintering furnace and evacuated to a vacuum of 5 × 10⁻⁶. - 2 After Pa, high-purity nitrogen gas is introduced as a protective atmosphere, and the temperature is raised to 750°C at a rapid heating rate of 150°C / min, while a uniaxial pressure of 80 MPa is applied. After reaching the target temperature, the temperature is held for 15 minutes.
[0053] After the heat preservation is completed, under pressure, water is forced to cool the temperature to below 200°C at the maximum cooling rate (>100°C / min), and then the pressure is released and the temperature is cooled to room temperature.
[0054] Demolding yields a dense, bulk modified nanocrystalline LATP solid electrolyte material.
[0055] Example 3:
[0056] Please see Figure 1 As shown, a method for preparing nano-LATP through low-temperature oxidation-dynamic sintering includes the following steps:
[0057] S1. Preparation of modified precursor mixture
[0058] According to stoichiometry, Li 1˙3 Al 0˙3 Ti 1˙7 (PO4)3 raw materials: lithium acetate (CH3COOLi·2H2O) as lithium source, aluminum nitrate (Al(NO3)3·9H2O) as aluminum source, titanium dioxide (TiO2, anatase type, nanoscale) as titanium source, ammonium dihydrogen phosphate (NH4H2PO4) as phosphorus source, and weigh out lithium borate (Li3BO3) equivalent to 0.5 wt.% of the theoretical mass fraction of LATP as borosilicate glass phase forming agent, and add La2O3 powder (replacing 1.5 at.% Ti).
[0059] All the above raw materials were dissolved / dispersed together in deionized water and stirred in a 70°C water bath to form a homogeneous suspension. Then, ammonia was slowly added dropwise to the solution as a precipitant until the pH reached 9.0, forming a coprecipitate. The coprecipitate was filtered, washed three times with deionized water and ethanol, dried at 100°C for 24 hours, and ground to obtain the modified precursor mixture powder.
[0060] S2. Segmented low-temperature oxidation heat treatment
[0061] The precursor powder obtained from S1 was placed in a corundum crucible and then placed in a box furnace.
[0062] First stage oxidation: The temperature is increased to 380°C at a rate of 10°C / min and kept at this temperature in air for 4 hours to completely remove bound water and residual ammonia salts.
[0063] Second stage oxidation: Continue heating at a rate of 5℃ / min to 620℃, and keep at this temperature in air for 6 hours to allow the solid-phase reaction to proceed fully, complete doping and preliminary crystallization, and obtain pre-oxidized powder.
[0064] After the reaction is complete, allow it to cool naturally to room temperature.
[0065] S3. Non-magnetic field sintering treatment
[0066] 0.3 wt.% of graphene nanosheets were added to the pre-oxidized powder obtained by S2, and sintered at 850℃ / 40MPa / 15min using SPS without applying a magnetic field. After reaching the target temperature, the temperature was held for 15 minutes. After the holding period, the temperature was forcibly cooled to below 200℃ by water at the maximum cooling rate (>100℃ / min) while maintaining the pressure. Then the pressure was released and the temperature was cooled to room temperature.
[0067] Demolding yields a dense, bulk modified nanocrystalline LATP solid electrolyte material.
[0068] Example 4:
[0069] The process and conditions were the same as in Example 2, except that the parameters were adjusted: only 0.2 wt.% B2O3 was added during precursor mixing, and no lanthanides were added. Nanoscale precursors were obtained using high-energy ball milling (500 rpm, 8 h) (other parameters were the same as in Example 2).
[0070] Example 5:
[0071] The process and conditions are the same as in Example 1, except that the parameters are adjusted as follows: Y2O3 (replacing 1 at.% Ti) and 2 wt.% H3BO3 are added to the precursor (other parameters are the same as in Example 1).
[0072] Example 6:
[0073] The process and conditions are the same as in Example 1, except that the step parameters are adjusted: the segmented oxidation is reduced from 400℃ / 3h to 550℃ / 3h (shortening the time). No two-dimensional materials are added; sintering is performed directly with SPS at 800℃ / 100MPa / 3min (extremely short time) under a 3T magnetic field. (Other parameters are the same as in Example 1).
[0074] Comparative Example 1:
[0075] According to stoichiometry, Li 1˙3 Al 0˙3 Ti 1˙7 Weigh the following analytically pure raw materials: lithium carbonate (Li2CO3), alumina (Al2O3), titanium dioxide (TiO2, rutile type) and diammonium hydrogen phosphate ((NH4)2HPO4). Place the above raw materials in a planetary ball mill and ball mill for 12 hours with ethanol as the medium. Dry the slurry at 100°C and pass it through a 200-mesh sieve to obtain a uniformly mixed precursor powder.
[0076] The precursor powder was placed in an alumina crucible and then placed in a box-type muffle furnace. In a static air atmosphere, the temperature was increased to 900°C at a rate of 5°C / min and held at this temperature for 10 hours to complete the solid-phase reaction and synthesize the LATP main crystalline phase. After cooling with the furnace, the pre-sintered block was taken out, re-ground into fine powder, and passed through a 300-mesh sieve.
[0077] The pre-sintered powder was dry-pressed into circular blanks with a diameter of 10 mm. The blanks were placed in a muffle furnace and heated to 1050 °C at a rate of 5 °C / min under air atmosphere. Static sintering was carried out at 1050 °C under normal pressure for 12 hours to obtain dense ceramic sheets. After sintering, the blanks were slowly cooled to room temperature at a rate of 3 °C / min.
[0078] Comparative Example 2:
[0079] The process and conditions are the same as in Example 1, except that the parameters are adjusted as follows: only the basic raw materials are weighed according to stoichiometry, and no boron or lanthanide elements are added (other parameters are the same as in Example 1).
[0080] Comparative Example 3:
[0081] The process and conditions are the same as in Example 1, except that the step parameters are adjusted as follows: Traditional atmospheric pressure sintering is adopted: 900℃ / 10h (no pressure, no magnetic field) (other parameters are the same as in Example 1).
[0082] Comparative Example 4:
[0083] The process and conditions are the same as in Example 1, except that the step parameters are adjusted as follows: directly raise the temperature to 600℃ and hold for 5 hours (without segmentation) (other parameters are the same as in Example 1).
[0084] Experimental example:
[0085] The materials prepared in the embodiments of the present invention are compared with the comparative materials representing the prior art through systematic performance testing and analysis.
[0086] All samples were analyzed using a systematic characterization and testing method: crystal structure and phase composition were analyzed using X-ray diffraction; microstructure was observed using field emission scanning electron microscopy, and the average grain size was calculated; the volume density was measured using the Archimedes displacement method, and the relative density was calculated; electrochemical impedance spectroscopy was performed at room temperature using an electrochemical workstation to accurately obtain the total ionic conductivity and grain boundary resistance ratio. The results are shown in the table below.
[0087] Group Average grain size (nm) Relative density (%) Ionic conductivity (S / cm) Grain boundary resistance percentage (%) Phase purity (XRD) Example 1 80 98.2 <![CDATA[8.7×10 -4 ]]> 18 No impurities Example 2 50 97.8 <![CDATA[1.2×10 -3 ]]> 15 No impurities Example 3 120 97.0 <![CDATA[7.2×10 -4 ]]> 22 No impurities Example 4 150 96.5 <![CDATA[5.8×10 -4 ]]> 28 <![CDATA[Trace TiO2]]> Example 5 200 98.5 <![CDATA[1.05×10 -3 ]]> 16 No impurities Example 6 100 96.0 <![CDATA[6.5×10 -4 ]]> 25 No impurities Comparative Example 1 3500 90.5 <![CDATA[2.1×10 -4 ]]> 62 <![CDATA[There are impurities (AlPO4, TiO2) <!-- 5 -->]]> Comparative Example 2 ~1000 92.0 <![CDATA[3.0×10 -4 ]]> 55 <![CDATA[There is impurity phase (TiO2)]]> Comparative Example 3 ~2000 89.0 <![CDATA[2.5×10 -4 ]]> 60 <![CDATA[There is impurity phase (TiO2)]]> Comparative Example 4 150 94.0 <![CDATA[2.8×10 -4 ]]> 48 <![CDATA[Obvious TiO2 heterophase]]>
[0088] As can be seen from the above, in terms of microstructure, the material in Comparative Example 1 has a large average grain size of about 3500 nanometers and a relative density of only 90.5%; while the grain size of Examples 1 and 2 of the present invention is refined to 80 nanometers and 50 nanometers respectively, and the relative density is significantly increased to about 98%.
[0089] In terms of core electrochemical performance, the room temperature total ionic conductivity of Comparative Example 1 is 2.1 × 10⁻⁶. -4 The grain boundary resistance is as high as 62% of the total resistance, becoming the main bottleneck for ion transport. At the same time, the proportion of grain boundary resistance is significantly reduced to 18% and 15%.
[0090] Phase analysis shows that the sample of the present invention has higher purity and no impurity phase peaks. In addition, in terms of process, the present invention reduces the maximum processing temperature from 1050℃ in the traditional method to below 800℃ and significantly shortens the total heat treatment time from 22 hours to less than 1 hour.
[0091] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.
Claims
1. A method for preparing nano-LATP through low-temperature oxidation-dynamic sintering, characterized in that, Includes the following steps: S1. Mix lithium source, aluminum source, titanium source and phosphorus source according to LATP stoichiometric ratio, and add at least one of boron glass phase forming agent or lanthanide doping modifier to prepare modified precursor mixture. S2. The modified precursor mixture is subjected to segmented low-temperature oxidation heat treatment in an oxygen-containing atmosphere to obtain pre-oxidized powder; S3. The pre-oxidized powder is subjected to dynamic sintering treatment to obtain modified nanocrystalline LATP solid electrolyte material.
2. The method for preparing nano-LATP through low-temperature oxidation-dynamic sintering according to claim 1, characterized in that: The boron-containing glass phase forming agent is at least one of boric acid, boron oxide, and lithium borate, and its addition amount is 0.1-5 wt.% of the theoretical mass fraction of LATP.
3. The method for preparing nano-LATP through low-temperature oxidation-dynamic sintering according to claim 1, characterized in that: The lanthanide-containing doping modifier is at least one of lanthanum oxide, cerium oxide, and yttrium oxide, and its addition amount is to replace 0.1-5 at.% of Ti sites in LATP.
4. The method for preparing nano-LATP through low-temperature oxidation-dynamic sintering according to claim 1, characterized in that, In step S1, the boron-containing glass phase forming agent is added by first dissolving the boron-containing glass phase forming agent in an organic solvent to form a solution, and then uniformly mixing it with the mixture of the lithium source, aluminum source, titanium source, and phosphorus source.
5. The method for preparing nano-LATP through low-temperature oxidation-dynamic sintering according to claim 1, characterized in that, The segmented low-temperature oxidation heat treatment in step S2 specifically includes: First stage: Keep warm at 300℃~450℃ for 1~5 hours; The second stage involves holding the temperature at 500℃ to 650℃ for 2 to 8 hours, during which a gaseous precursor containing lanthanide elements is introduced as a dopant for gas-phase assisted doping.
6. The method for preparing nano-LATP through low-temperature oxidation-dynamic sintering according to claim 1, characterized in that: The gaseous precursor is at least one of lanthanide acetylacetonates, cyclopentadienyl compounds, or halides.
7. The method for preparing nano-LATP through low-temperature oxidation-dynamic sintering according to claim 1, characterized in that, The dynamic sintering treatment in step S3 adopts spark plasma sintering, with the following process parameters: sintering temperature of 700℃~900℃, sintering pressure of 30~100MPa, holding time of 5~30 minutes, and a strong magnetic field of 0.1-10T is applied simultaneously with pulsed current during the sintering process.
8. The method for preparing nano-LATP through low-temperature oxidation-dynamic sintering according to claim 1, characterized in that: The direction of the strong magnetic field is perpendicular to or at a specific angle to the direction of the pulse current, and the magnetic field strength is 1-5T.
9. The method for preparing nano-LATP through low-temperature oxidation-dynamic sintering according to claim 1, characterized in that: In step S3, 0.01-2 wt.% of two-dimensional nanomaterials are added to the pre-oxidized powder as grain boundary reinforcing agents before dynamic sintering. The two-dimensional nanomaterials include, but are not limited to, hexagonal boron nitride nanosheets, transition metal carbonitrides MXene, or graphene nanosheets.