Disordered niobium-based oxide material, preparation method and application thereof and lithium ion battery

Abstract

This invention provides a disordered niobium-based oxide material, its preparation method, and its application in lithium-ion batteries. The preparation method includes the following steps: acid etching a niobium-based perovskite precursor to obtain an amorphous precursor; subjecting the amorphous precursor to Joule thermal shock heating to obtain the disordered niobium-based oxide material. The disordered niobium-based oxide material prepared by this invention effectively optimizes lithium-ion migration channels and electron transport paths by introducing atomic arrangement disorder and defect regulation, thereby significantly improving the material's high-rate performance and cycle stability.

Description

TECHNICAL FIELD

[0001] The present application relates to a disordered niobium-based oxide material, a preparation method, and applications thereof in lithium-ion batteries. BACKGROUND

[0002] With the rapid development of renewable energy and electric transportation, there is an increasing demand for lithium-ion batteries with high power, high energy density, and long cycle life. In applications such as electric vehicles, smart grid energy storage, and portable electronic devices, batteries not only need to provide stable energy output, but also must have fast charging and discharging capabilities and long cycle life to meet the needs of high-frequency use and extreme environmental conditions. The performance of high-rate charging and discharging directly determines the reliability and safety of the battery in fast-starting, grid peak-shaving, and high-power output scenarios. Therefore, developing new high-performance negative electrode materials has become one of the focuses of current battery technology research. Titanium niobium oxide (Ti2Nb 10 O 29 ) exhibits significant advantages in negative electrode materials due to its unique crystal structure and chemical properties. First, its theoretical capacity is close to 400 mAh / g, much higher than that of traditional graphite negative electrodes. Second, titanium niobium oxide has minimal volume change during charging and discharging, making it a near-zero expansion material with good structural stability, which helps achieve long cycle life. At the same time, its open framework structure provides stable lithium ion migration channels, enabling excellent electrochemical performance at high rates. However, existing research also shows that titanium niobium oxide negative electrodes still have significant limitations in practical applications.

[0003] The intrinsic electronic conductivity of titanium niobium oxide negative electrode materials is low, limiting the efficiency of electron transport at high rates. Second, although its open framework structure provides migration channels for lithium ions, the highly ordered crystal structure still has limited lithium ion migration during fast charging and discharging, which can cause local ion transport bottlenecks, leading to a decrease in high-rate performance. In addition, the ordered crystal structure lacks lattice defects and micro-tortuosity, which is not conducive to improving the electronic conductivity and ion diffusion dynamics of the material. Traditional titanium niobium oxide has limited performance under fast charging and discharging conditions, making it difficult to meet the requirements of high power and high reliability in practical applications.

[0004] In existing technologies, titanium niobium oxide is mainly synthesized by a solid-phase method. This method usually requires slow heating to high temperatures and maintaining long-term reactions, which has a long process cycle and high energy consumption. In addition, long-term high-temperature reactions result in the synthesized product having a highly ordered crystal structure, which limits the rapid migration of lithium ions at high rates and can cause local stress accumulation, affecting cycle stability and rate performance. Therefore, improving the high-rate performance and cycle stability of new titanium niobium oxide negative electrode materials is a technical problem that needs to be solved in the field. SUMMARY

[0005] The technical problem solved by the present application is to overcome the defects of slow heating rate, long reaction time, highly ordered titanium / niobium atomic arrangement, limited lithium ion migration and decreased electrochemical performance at high rate of the conventional solid phase method for preparing titanium-niobium oxide negative electrode material in the prior art, and to provide an unordered niobium-based oxide material and a preparation method, application and lithium ion battery thereof.

[0006] The unordered niobium-based oxide material prepared by the present application can effectively optimize the lithium ion migration channel and electron transport path by introducing atomic arrangement disorder and defect regulation, thereby significantly improving the high rate performance and cycle stability of the material.

[0007] The present application solves the above technical problems by the following technical solutions:

[0008] The present application provides a preparation method of an unordered niobium-based oxide material, which comprises the following steps:

[0009] After acid etching of the niobium-based perovskite precursor, an amorphous precursor is prepared; the amorphous precursor is subjected to joule heat shock heating to obtain the unordered niobium-based oxide material.

[0010] In the present application, the niobium-based perovskite precursor refers to a perovskite precursor partially substituted by niobium. The chemical formula of the niobium-based perovskite precursor is preferably A x M y Nb z O3, wherein A is one or more of alkaline earth metals, and M is Ti and / or W.

[0011] In the chemical formula, A is preferably one or more of Mg, Ca, Sr and Ba.

[0012] In the chemical formula, the sum of the values of x, y and z generally needs to satisfy the sum of the valence of the chemical formula being zero.

[0013] In the formula, preferably, 0

[0014] In the formula, preferably, 0.05

[0015] In the formula, preferably, 0.2

[0016] In some embodiments, the Nb-based perovskite precursor has a chemical formula of SrCa 0.295 Ti 0.1175 Nb 0.5875 O3or SrCa 0.3725 W 0.11 Nb 0.5175 O3.

[0017] In the present application, the Nb-based perovskite precursor can be prepared by a method conventional in the art, such as a sol-gel method. When the Nb-based perovskite precursor has a chemical formula of A x M y Nb z O3, the method for preparing the Nb-based perovskite precursor preferably comprises the following steps: heating and mixing a mixed solution containing a salt of A, a salt of M, a salt of Nb, a complexing agent and a solvent to form a gel, and calcining the gel to prepare the Nb-based perovskite precursor.

[0018] The salt of A can be one or more of hydrochloride, sulfate and nitrate of metal A. The salt of M can be one or more of hydrochloride, sulfate and nitrate of metal A. The salt of Nb can be one or more of hydrochloride, sulfate and nitrate of Nb.

[0019] In some embodiments, the salt of A can be SrCl2and / or CaCl2.

[0020] In some embodiments, the salt of M is TiCl4or WCl6.

[0021] In some embodiments, the salt of Nb is NbCl5.

[0022] In the formula, the molar ratio of the salt of A, the salt of M and the salt of Nb can be added according to the stoichiometric ratio.

[0023] The complexing agent may be other polycarboxylic acids and / or hydroxycarboxylic acids, such as citric acid.

[0024] The ratio of the sum of the masses of the A salt, M salt, and Nb salt to the mass of the complexing agent can be conventional in the art, preferably (0.1-0.8):1, for example 0.2:1, 0.25:1, 0.26:1, 0.28:1, 0.29:1, 0.3:1, 0.32:1, 0.33:1, 0.35:1, 0.37:1, 0.38:1, 0.4:1, 0.5:1, or 0.6:1.

[0025] The solvent may be conventional in the art, and preferably one or more of deionized water, ethanol and ethylene glycol.

[0026] In some specific embodiments, the solvent is a mixture of deionized water, ethanol and ethylene glycol in a volume ratio of 1:2:1.

[0027] Preferably, the sum of the masses of the A salt, the M salt, the Nb salt, and the complexing agent, compared to the volume of the solvent, is (0.01-0.8) g / mL, for example, 0.05 g / mL, 0.08 g / mL, 0.1 g / mL, 0.15 g / mL, 0.2 g / mL, 0.3 g / mL, 0.4 g / mL, or 0.5 g / mL.

[0028] The method for preparing the mixture containing A salt, M salt, Nb salt, complexing agent and solvent is conventional in the art, and preferably includes the following steps: adding A salt, M salt, Nb salt and complexing agent to solvent and mixing until completely dissolved.

[0029] The heating and mixing temperature can be 60-120℃, for example 80℃, 90℃, 95℃ or 100℃; the heating and mixing time can be 3-12h, preferably 4-10h, for example 6h, 8h or 10h.

[0030] The calcination is generally carried out in an air atmosphere. The calcination temperature can be 500-900℃, for example 600℃, 700℃ or 800℃; the calcination time can be 1-6h, for example 2h, 3h or 4h.

[0031] In this invention, the acid used for acid etching can be of a type conventional in the art, generally one or more of hydrochloric acid, sulfuric acid, and nitric acid, for example, hydrochloric acid. The concentration of the acid used for acid etching can be 0.5-5M, for example, 1M, 2M, 3M, or 4M.

[0032] In some specific embodiments, the acid used for acid etching is 3M hydrochloric acid.

[0033] In this invention, the ratio of the mass of the niobium-based perovskite precursor to the volume of the acid used for acid etching can be (0.005-0.1) g / mL, preferably (0.005-0.05) g / mL, for example 0.01 g / mL, 0.015 g / mL, 0.03 g / mL or 0.04 g / mL.

[0034] In this invention, the acid etching preferably includes the following steps: subjecting a mixture of niobium-based perovskite precursor and acid to a hydrothermal reaction.

[0035] The hydrothermal reaction typically requires the reactants to be placed in a sealed, high-pressure stainless steel reactor lined with polytetrafluoroethylene for heating and reaction.

[0036] The temperature of the hydrothermal reaction can be 150-250℃, for example 180℃, 190℃, 200℃, 210℃ or 220℃; the time of the hydrothermal reaction can be 6-24h, for example 8h, 10h, 11h, 12h, 14h or 16h.

[0037] After the hydrothermal reaction is completed, washing and drying are generally required, according to conventional practices in the art. The washing method can be conventional, such as magnetic stirring and / or ultrasound; the solvent used for washing is generally deionized water; and the number of washing cycles can be conventional, such as 3-5 times.

[0038] In this invention, the Joule thermal shock heating refers to pulse heating treatment of the amorphous precursor using a Joule thermal high-temperature furnace.

[0039] In this invention, the temperature for Joule thermal shock heating can be 700-1500℃, for example 750℃, 800℃, 900℃, 1000℃, 1050℃, 1100℃, 1200℃, 1300℃ or 1400℃, preferably 950-1050℃; the holding time for Joule thermal shock heating can be 10-50 s, for example 15s, 20s, 25s, 30s, 32s, 35s, 38s, 40s or 45s, preferably 15-32s.

[0040] In this invention, the number of pulses for Joule thermal shock heating can be 1-5 times, for example, 1 time, 2 times or 3 times.

[0041] Preferably, in some embodiments, the holding time for Joule thermal shock heating is 15-32 seconds, and the number of pulses is 1.

[0042] More preferably, in some embodiments, the holding time for Joule thermal shock heating is 15-32 seconds, the number of pulses is 1, and the temperature for Joule thermal shock heating is 900-1400°C.

[0043] More preferably, in some embodiments, the niobium-based perovskite precursor has the chemical formula SrCa. 0.295 Ti 0.1175 Nb 0.5875 O3, wherein the holding time for Joule thermal shock heating is 18-32s, the number of pulses is 1, and the temperature for Joule thermal shock heating is 900-1400℃.

[0044] In one specific implementation, the Joule thermal shock heating process is as follows: pulse heating to 1000°C once and holding at that temperature for 30 seconds.

[0045] In a preferred embodiment, the niobium-based perovskite precursor has the chemical formula SrCa. 0.295 Ti 0.1175 Nb 0.5875 O3, the process of Joule thermal shock heating is as follows: pulse heating to 1000℃ once and holding at that temperature for 30s.

[0046] In one specific implementation, the Joule thermal shock heating process is as follows: pulse heating to 1000°C once and holding for 15 seconds, then cooling, and then pulse heating to 1000°C once more and holding for 15 seconds.

[0047] In this invention, after the Joule thermal shock heating is completed, the temperature can generally be cooled down naturally.

[0048] The present invention also provides a disordered niobium-based oxide material prepared by the preparation method described above.

[0049] In this invention, the chemical formula of the disordered niobium-based oxide material can be Ti2Nb. 10 O 29 or Nb 14 W3O 44 .

[0050] In this invention, the disorder in the disordered niobium-based oxide material refers to the situation where the position of titanium or tungsten / niobium atoms in the crystal lattice deviates from the standard titanium or tungsten / niobium atom occupancy probability.

[0051] In this invention, when the chemical formula of the disordered niobium-based oxide material is Ti2Nb 10 O 29When the isotropic atomic displacement parameter ratio (Ti / Nb) is preferably 2-3.5, for example 2.3, 2.5, 2.6, 2.73, 2.8, 2.9 or 3. The isotropic atomic displacement parameter ratio can be obtained by testing and fitting the atomic pair distribution function.

[0052] The present invention also provides an application of the disordered niobium-based oxide material as described above in lithium-ion batteries.

[0053] The present invention also provides a lithium-ion battery comprising a positive electrode, a negative electrode, and an electrolyte, wherein the negative electrode comprises the disordered niobium-based oxide material.

[0054] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of the present invention.

[0055] The reagents and raw materials used in this invention are all commercially available.

[0056] The positive and progressive effects of this invention are as follows:

[0057] This invention utilizes an amorphous precursor combined with an ultrafast Joule thermal shock method to prepare disordered titanium-niobium oxide anodes, successfully achieving the disordered distribution of titanium or tungsten / niobium atoms and the introduction of oxygen vacancies. Compared with ordered titanium-niobium oxide anodes prepared by traditional solid-state methods, this invention effectively improves lithium-ion migration channels and electron transport paths, significantly enhancing the charge-discharge performance of niobium-based oxide materials at high rates. Attached Figure Description

[0058] Figure 1 The XRD pattern of the disordered titanium niobium oxide anode material prepared in Example 1;

[0059] Figure 2 The XRD pattern of the disordered tungsten niobium oxide anode material prepared in Example 8;

[0060] Figure 3 The graph shows the cycling performance of the disordered titanium niobium oxide anode material prepared in Example 1 at a current density of 10 C.

[0061] Figure 4 The graph shows the cycling performance of the disordered titanium niobium oxide anode material prepared in Example 2 at a current density of 10 C.

[0062] Figure 5 The graph shows the cycling performance of the disordered titanium niobium oxide anode material prepared in Example 3 at a current density of 10 C.

[0063] Figure 6 The graph shows the cycling performance of the disordered titanium niobium oxide anode material prepared in Example 4 at a current density of 10 C.

[0064] Figure 7 The graph shows the cycling performance of Comparative Example 1 at a current density of 10 C. Detailed Implementation

[0065] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments that do not specify specific conditions were performed according to conventional methods and conditions, or as selected according to the product instructions.

[0066] Example 1

[0067] Step 1: Mix 7.5 mL of deionized water, 15 mL of ethanol, and 7.5 mL of ethylene glycol thoroughly to form a solvent system. Add 0.477 g SrCl2, 0.098 g CaCl2, 0.067 g TiCl4, 0.476 g NbCl5, and 3.500 g citric acid sequentially to the solvent, stirring thoroughly until all components are completely dissolved. Stir the mixture continuously at 90°C for 8 hours until a homogeneous gel forms.

[0068] Step 2: Place the gel in a muffle furnace and heat at 700°C in air for 3 hours to obtain the precursor SrCa. 0.295 Ti 0.1175 Nb 0.5875 O3 was used to place the above product (0.200 g) into a stainless steel sealed high-pressure reactor with a polytetrafluoroethylene liner. 13 mL of 3 M hydrochloric acid was added, and the reactor was placed in an oven at 200 °C for 12 h. After the reaction was completed, the product was washed three times with deionized water and dried in a 60 °C forced-air drying oven to obtain an amorphous precursor.

[0069] Step 3: The amorphous precursor was placed in an ultrafast Joule heating high-temperature furnace (Padick Precision Instruments Co., Ltd., 2022A-8). The cavity was purged with vacuum and inert gas (Ar) three times. Then, the gas pressure was maintained at -0.05 MPa. Subsequently, the amorphous precursor was heated to 1000℃ using an ultrafast Joule thermal shock device, pulsed once, held at that temperature for 30 s, and then allowed to cool naturally to obtain Ti2Nb. 10 O 29 (TNO) negative electrode material.

[0070] Example 2

[0071] Step 1: Same as Example 1;

[0072] Step 2: Same as Example 1;

[0073] Step 3: Except for heat treatment of the amorphous precursor by an ultrafast Joule thermal shock device for 20 seconds, all other operations and conditions are the same as in Example 1.

[0074] Example 3

[0075] Step 1: Same as Example 1;

[0076] Step 2: Same as Example 1;

[0077] Step 3: Except for heat treatment of the amorphous precursor by an ultrafast Joule thermal shock device for 35 seconds, all other operations and conditions are the same as in Example 1.

[0078] Example 4

[0079] Step 1: Same as Example 1;

[0080] Step 2: Same as Example 1;

[0081] Step 3: Except for heat treatment of the amorphous precursor by an ultrafast Joule thermal shock device for 40 seconds, all other operations and conditions are the same as in Example 1.

[0082] Example 5

[0083] Step 1: Same as Example 1;

[0084] Step 2: Same as Example 1;

[0085] Step 3: Except for heating the amorphous precursor twice with an ultrafast Joule thermal shock device, all other operations and conditions are the same as in Example 1; the process of two pulses is as follows: heat to 1000°C with one pulse and hold for 15 seconds, then cool naturally to room temperature, then heat to 1000°C with another pulse and hold for 15 seconds, then cool naturally.

[0086] Example 6

[0087] Step 1: Same as Example 1;

[0088] Step 2: Same as Example 1;

[0089] Step 3: Except for heating the amorphous precursor to 1100°C using an ultrafast Joule thermal shock device, all other operations and conditions are the same as in Example 1.

[0090] Example 7

[0091] Step 1: Same as Example 1;

[0092] Step 2: Same as Example 1;

[0093] Step 3: Except for heating the amorphous precursor to 1300°C using an ultrafast Joule thermal shock device, all other operations and conditions are the same as in Example 1.

[0094] Example 8

[0095] Step 1: Mix 7.5 mL of deionized water, 15 mL of ethanol, and 7.5 mL of ethylene glycol thoroughly to form a solvent system. Add 0.477 g SrCl2, 0.124 g CaCl2, 0.131 g WCl6, 0.419 g NbCl5, and 3.500 g citric acid sequentially to the solvent, stirring thoroughly until all components are completely dissolved. Stir the mixture continuously at 90°C for 8 hours until a homogeneous gel forms.

[0096] Step 2: Place the gel in a muffle furnace and heat at 700°C in air for 3 hours to obtain the precursor SrCa. 0.3725 W 0.11 Nb 0.5175 O3 was used to place the above product (0.200 g) into a stainless steel sealed high-pressure reactor with a polytetrafluoroethylene liner. 13 mL of 3 M hydrochloric acid was added, and the reactor was placed in an oven at 200 °C for 12 h. After the reaction was completed, the product was washed three times with deionized water and dried in a 60 °C forced-air drying oven to obtain an amorphous precursor.

[0097] Step 3: The amorphous precursor was placed in an ultrafast Joule heating furnace (Padick Precision Instruments Co., Ltd., 2022A-8). The cavity was purged with vacuum and inert gas (Ar) three times. The pressure was then maintained at -0.05 MPa. The amorphous precursor was then heated to 1000°C with a single pulse heating, held for 30 s, and then rapidly cooled to obtain Nb. 14 W3O 44 (NWO) negative electrode material.

[0098] Comparative Example 1

[0099] Step 1: Weigh 0.332 g Nb2O5 and 0.040 g TiO2, grind them in a mortar for 20 min, and use the obtained powder as a solid-phase reaction precursor.

[0100] Step 2: The solid-state reaction precursor powder was placed in a muffle furnace, heated to 1000℃ at a heating rate of 5℃ / min, and sintered for 7 h to obtain S-Ti2Nb with ordered atomic arrangement. 10 O 29 (S-TNO) negative electrode material.

[0101] Effect Example

[0102] (1) Characterization of material properties

[0103] Phase characterization of the samples from each embodiment was performed using a Bruker D2 phase diffractometer. Powder samples from the embodiments were placed on an X-ray diffraction stage, and the powder surface was smoothed using a glass slide. The test results are as follows: Figure 1 and Figure 2As shown, according to Figure 1 and Figure 2 It can be seen that the target product with high crystallinity can be prepared according to the schemes of Example 1 and Example 8.

[0104] (2) Test and analysis of the distribution function of atomic pairs

[0105] The powder samples of each embodiment and comparative example were loaded into borosilicate glass capillaries with a diameter of 0.5 mm, and their scattering intensity was tested at room temperature. The local structure was refined using the PDF modeling program PDF gui, and the refinement results are shown in Table 1.

[0106] (3) Electrochemical performance testing

[0107] Under the same experimental conditions, the disordered oxide anode materials prepared in each embodiment and the ordered oxide anode materials prepared in the comparative example were used as samples to assemble lithium-ion batteries.

[0108] Negative electrode preparation: The samples prepared in each example and comparative example were mixed with conductive carbon (superP) and binder polyvinylidene fluoride in a mass ratio of 8:1:1. N-methylpyrrolidone solvent was injected into the mixture powder, and the mixture was stirred in a homogenizer for 15 min. The resulting slurry was coated onto copper foil and dried in a vacuum drying oven at 100°C for 12 h. The resulting electrode was then stamped into electrode sheets (12 mm in diameter) using a circular hole punch, with an average loading mass of approximately 1 mg / cm². 2 Used for button cell battery assembly.

[0109] Button cell assembly: Lithium-ion batteries were assembled using a CR2032 button cell mold. The negative electrode was lithium metal, and a GF / D glass fiber separator was used to separate the positive and negative electrodes. The battery interior was immersed in a 1 mol / L lithium hexafluorophosphate electrolyte solution in a 1:1 mass ratio of dimethyl carbonate and ethylene carbonate. After encapsulation and settling, electrochemical performance testing was performed. Ti2Nb 10 O 29 The theoretical 1C value for the negative electrode is 396 mAh / g. (Nb) 14 W3O 44 The theoretical value of the negative electrode at 1C is 356 mAh / g.

[0110] Electrochemical performance testing: The prepared coin cells were subjected to cycle performance testing within a voltage range of 1.0-3.0 V. The test results are shown in Tables 2-3 and 3. Figures 3-7 As shown.

[0111] Table 1

[0112] Isotropic atomic displacement parameter (Ti) Isotropic atomic displacement parameter ratio (Nb) Isotropic atomic displacement parameter ratio (Ti / Nb) Example 1 0.02512 0.00920 2.73 Comparative Example 1 0.01712 0.00964 1.78

[0113] As shown in Table 1, Example 1 has a higher ratio of isotropic atomic displacement parameters, which means a higher degree of disorder in the arrangement of titanium / niobium atoms.

[0114] Table 2

[0115] 1C discharge specific capacity (mAh / g) 10C discharge specific capacity (mAh / g) 150C discharge specific capacity (mAh / g) Example 1 275 188 110 Example 2 230 160 68 Example 3 208 116 53 Example 4 210 119 49 Example 5 189 107 39 Example 6 212 174 63 Example 7 198 160 58 Example 8 205 145 40 Comparative Example 1 145 98 2

[0116] Table 3

[0117] 0.5C discharge specific capacity (mAh / g) 10C cycle life (times) Example 1 290 5000 Example 2 252 3000 Example 3 233 2000 Comparative Example 1 160 1000

[0118] As shown in Tables 2 and 3, the disordered oxide anode material prepared in the examples has a high discharge specific capacity and excellent cycle stability, especially excellent high-rate charge-discharge performance.

[0119] While specific embodiments of the present invention have been described above, those skilled in the art should understand that these are merely illustrative examples, and the scope of protection of the present invention is defined by the appended claims. Those skilled in the art can make various changes or modifications to these embodiments without departing from the principles and essence of the present invention, but all such changes and modifications fall within the scope of protection of the present invention.

Claims

1. A method for preparing a disordered niobium-based oxide material, characterized in that, Includes the following steps: An amorphous precursor is prepared by acid etching of a niobium-based perovskite precursor; the amorphous precursor is then subjected to Joule thermal shock heating to obtain the disordered niobium-based oxide material.

2. The method for preparing disordered niobium-based oxide materials as described in claim 1, characterized in that, The preparation method satisfies one or more of the following conditions: (1) The chemical formula of the niobium-based perovskite precursor is A x M y Nb z O3, wherein A is one or more alkaline earth metals, and M is Ti and / or W; Preferably, the chemical formula of the niobium-based perovskite precursor is SrCa. 0.295 Ti 0.1175 Nb 0.5875 O3 or SrCa 0.3725 W 0.11 Nb 0.5175 O3; (2) The acid used in the acid etching is one or more of hydrochloric acid, sulfuric acid and nitric acid; (3) The concentration of acid used in the acid etching can be 0.5-5M, for example 1M, 2M, 3M or 4M; (4) The ratio of the mass of the niobium-based perovskite precursor to the volume of the acid used for acid etching is (0.005-0.1) g / mL, preferably (0.005-0.05) g / mL, for example 0.01 g / mL, 0.015 g / mL, 0.03 g / mL or 0.04 g / mL.

3. The method for preparing disordered niobium-based oxide materials as described in claim 2, characterized in that, The chemical formula of the niobium-based perovskite precursor satisfies one or more of the following conditions: (1) In the chemical formula, 0 < x < 2, preferably 1 < x < 2, for example x is 1.1, 1.2, 1.295, 1.3, 1.35, 1.3725, 1.4 or 1.5; (2) In the chemical formula, 0.05 < y < 0.3, preferably 0.05 < y < 0.2, for example y is 0.06, 0.08, 0.1, 0.11, 0.1175, 0.13 or 0.15; (3) In the chemical formula, 0.2 < z < 1, preferably 0.3 < z < 0.8, for example z is 0.34, 0.4, 0.45, 0.5, 0.5175, 0.53, 0.55, 0.5875, 0.6 or 0.7; (4) In the chemical formula, A is one or more of Mg, Ca, Sr and Ba.

4. The method for preparing disordered niobium-based oxide materials as described in claim 1, characterized in that, When the chemical formula of the niobium-based perovskite precursor is A x M y Nb z When O3 is present, the preparation method of the niobium-based perovskite precursor includes the following steps: heating and mixing a mixture containing A salt, M salt, Nb salt, complexing agent and solvent to form a gel, and calcining the gel to obtain the niobium-based perovskite precursor; And / or, the acid etching includes the following steps: hydrothermal reaction of a mixture of niobium-based perovskite precursor and acid.

5. The method for preparing the disordered niobium-based oxide material as described in claim 4, characterized in that, The method for preparing the niobium-based perovskite precursor satisfies one or more of the following conditions: (1) The A salt is one or more of the hydrochloride, sulfate and nitrate salts of metal A; (2) The M salt is one or more of the hydrochloride, sulfate and nitrate salts of metal A; (3) The Nb salt is one or more of the following: hydrochloride, sulfate, and nitrate of Nb; (4) The complexing agent is other polycarboxylic acids and / or hydroxycarboxylic acids, such as citric acid; (5) The ratio of the sum of the masses of the A salt, M salt and Nb salt to the mass of the complexing agent is (0.1-0.8):1; (6) The solvent is one or more of deionized water, ethanol, and ethylene glycol; (7) The ratio of the sum of the masses of the A salt, the M salt, the Nb salt and the complexing agent to the volume of the solvent is (0.01-0.8) g / mL; (8) The heating and mixing temperature is 60-120°C, for example 80°C, 90°C, 95°C or 100°C; (9) The heating and mixing time is 3-12 hours, for example, 6 hours, 8 hours or 10 hours; (10) The calcination temperature is 500-900℃, for example 600℃, 700℃ or 800℃; (11) The calcination time is 1-6h, for example 2h, 3h or 4h.

6. The method for preparing the disordered niobium-based oxide material as described in claim 4, characterized in that, The temperature of the hydrothermal reaction is 150-250℃, for example 180℃, 190℃, 200℃, 210℃ or 220℃; And / or, the hydrothermal reaction time is 6-24 hours, for example 8 hours, 10 hours, 11 hours, 12 hours, 14 hours or 16 hours.

7. The method for preparing disordered niobium-based oxide materials as described in claim 1, characterized in that, The Joule thermal shock heating process satisfies one or more of the following conditions: (1) The temperature for Joule thermal shock heating is 700-1500℃, for example 750℃, 800℃, 900℃, 1000℃, 1050℃, 1100℃, 1200℃, 1300℃ or 1400℃; (2) The holding time for Joule heat shock heating is 10-50s, for example 15s, 20s, 25s, 30s, 32s, 35s, 38s, 40s or 45s; (3) The number of pulses for Joule thermal shock heating is 1-5 times, for example, 1 time, 2 times or 3 times.

8. A disordered niobium-based oxide material prepared by the preparation method according to any one of claims 1-7; in, The chemical formula of the disordered niobium-based oxide material is preferably Ti2Nb. 10 O 29 or Nb 14 W3O 44 ; When the chemical formula of the disordered niobium-based oxide material is Ti2Nb 10 O 29 When the isotropic atomic displacement parameter ratio (Ti / Nb) is preferably 2-3.5, for example 2.3, 2.5, 2.6, 2.73, 2.8, 2.9 or 3.

9. The application of the disordered niobium-based oxide material as described in claim 8 in a lithium-ion battery.

10. A lithium-ion battery, characterized in that, It includes a positive electrode, a negative electrode, and an electrolyte, wherein the negative electrode comprises the disordered niobium-based oxide material as described in claim 8.

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