Preparation method and application of anion-doped Wadsley-Roth phase material
The preparation of anion-doped Wadsley-Roth phase materials by a solid-state method solves the problems of high cost, pollution, and difficulty in large-scale production in traditional preparation processes. It achieves efficient doping and uniform mixing of materials, thereby improving the electrochemical performance of lithium-ion batteries.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUAZHONG UNIV OF SCI & TECH
- Filing Date
- 2026-01-28
- Publication Date
- 2026-05-01
AI Technical Summary
The preparation of traditional Wadsley-Roth phase materials is characterized by high cost, significant pollution, flammability and safety concerns, complex processes, and limited scalability. Furthermore, the materials exhibit low ionic and electronic conductivity and unstable interfaces, which restricts their application in lithium-ion batteries.
Anion-doped Wadsley-Roth phase materials were prepared using a solid-state method. By dispersing solid-state compounds of titanium, niobium and anion sources with different particle sizes, uniform mixing was achieved by utilizing the differences in particle surface energy, avoiding the use of solvents. Subsequently, the mixture was heat-treated under oxygen-containing conditions to form a uniform crystal structure.
The material achieves uniform mixing and efficient doping, improving ionic and electronic conductivity, reducing production costs and environmental risks. It exhibits excellent specific capacity, rate performance, and cycle performance, making it suitable as a negative electrode material for lithium-ion batteries.
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Figure CN121948544A_ABST
Abstract
Description
Preparation methods and applications of anion-doped Wadsley-Roth phase materials Technical Field
[0001] This invention belongs to the field of lithium-ion battery technology, specifically relating to a method for preparing and applying anion-doped Wadsley-Roth phase materials. Background Technology
[0002] Traditional graphite anodes suffer from safety issues such as slow lithium-ion migration, low operating potential, poor rate capability, low temperature performance, and dendrite formation risk due to their slow lithium-ion migration. Lithium titanate (Li4Ti5O4) 12 It can avoid dendrite formation and has high safety, but its theoretical specific capacity is low, which limits its applications.
[0003] Wadsley-Roth phase materials have similar working potentials to lithium titanate, small volume changes, and stable structures. Their theoretical specific capacity is close to that of graphite, and they have high density. They are expected to improve both mass and volumetric energy, making them suitable as high-safety anodes.
[0004] Currently, the preparation of Wadsley-Roth phase materials mostly uses wet processes such as water / ethanol / propylene glycol, which require drying solvents, resulting in high costs, significant pollution, flammability and safety risks, complex processes, and difficulties in large-scale production. Summary of the Invention
[0005] In view of this, the present invention provides a method for preparing anion-doped Wadsley-Roth phase materials and their application. The entire process does not use solvents and can effectively solve the inherent low ionic conductivity, electronic conductivity and interfacial instability of traditional Wadsley-Roth phase materials, enabling the materials to undergo extreme high-current charge-discharge and ultra-long cycling.
[0006] To achieve the above objectives, the present invention adopts the following technical solution: Firstly, the present invention provides a method for preparing anion-doped Wadsley-Roth phase materials. The raw materials for preparing the anion-doped Wadsley-Roth phase materials include: a titanium-based solid-phase compound, a niobium-based solid-phase compound, and an anion-based solid-phase compound. The method for preparing the anion-doped Wadsley-Roth phase materials includes the following steps: S1, dispersing the titanium-based solid-phase compound, the niobium-based solid-phase compound, and the anion-based solid-phase compound separately until their size is the size of primary particles, wherein the primary particle sizes of the different solid-phase compounds are different from each other; S2, mixing and dispersing the dispersed titanium-based solid-phase compound, niobium-based solid-phase compound, and anion-based solid-phase compound to obtain a precursor; S3, heat-treating the precursor under oxygen-containing conditions to obtain the anion-doped Wadsley-Roth phase material.
[0007] In some embodiments, the anion-doped Wadsley-Roth phase material is a niobium oxide-based Wadsley-Roth phase material, preferably a pure phase TiNb2O7 or Ti2Nb with a stoichiometric ratio of cations to anions. 10 O 29 TiNb 24 O 62 or Nb 16 W5O 55 Correspondingly, the raw materials are selected from: titanium-based solid compounds, niobium-based solid compounds, and tungsten-based solid compounds.
[0008] It should be noted that in step S2 of this invention, after the compound is mixed, it is also dispersed so that the smaller raw material particles of different particle sizes are uniformly attached to the surface of the larger raw material particles. The uniform attachment of small raw material particles to the surface of large raw material particles results in a uniformly mixed precursor. This is because, during the solid-state mixing process, the differences in density, particle size, and specific surface area of the primary particles of various raw materials lead to differences in particle mass, surface energy, and powder energy. This causes small particles to spontaneously adsorb onto the surface of large particles, reducing the total energy of the system and achieving an energy-stable state, resulting in a uniform mixture of raw materials. This effectively avoids material stratification and uneven agglomeration, allowing anions to be uniformly doped into the crystal structure and surface of the Wadsley-Roth phase material during subsequent heat treatment. In other words, during the solid-state mixing process, the differences in particle mass, surface energy, and powder energy caused by the differences in density, particle size, and specific surface area of the primary particles of various raw materials cause small particles to spontaneously adsorb onto the surface of large particles, reducing the total energy and achieving an energy-stable state, resulting in a uniform mixture of raw materials. However, when using organic solvents as dispersants to disperse raw materials in traditional preparation methods, various raw materials used to prepare Wadsley-Roth phase materials will exhibit stratification during the solvent drying process, resulting in uneven material mixing.
[0009] In the above technical solutions, the use of anion-doped Wadsley-Roth phase materials has the following advantages: 1. Optimized lithium storage mechanism and improved reversible capacity. 2. Improved ionic conductivity and significantly reduced activation energy for lithium-ion migration. 3. Enhanced electronic conductivity, greatly improving the intrinsic electronic conductivity of the material. Increased electronic conductivity means a reduction in the overall internal resistance of the electrode, higher utilization of active materials, especially under high current, reduced electrode polarization, better voltage plateau maintenance, and more complete capacity utilization.
[0010] Preferably, the niobium source solid-phase compound includes at least one of Nb₂O₅, Nb(OH)₅, and Nb₂O₅; and / or, the titanium source solid-phase compound includes TiO₂; and / or, the anion source solid-phase compound includes at least one of LiF, NaF, KF, NH₃F, LiCl, NaCl, KCl, and NH₃Cl. It should be noted that in some embodiments, the anion element is one or both of F and Cl. During the raw material dispersion process, the primary particle size of the anion source is the smallest, so that it has a large specific surface area and can be uniformly dispersed on the surface of other raw material particles.
[0011] Preferably, the anion-doped Wadsley-Roth phase material includes anion elements and oxygen elements, wherein the atomic ratio of anion elements to oxygen elements is less than 0.1.
[0012] Preferably, in step S1, the equipment used to disperse the titanium source solid compound, the niobium source solid compound, and the anion source solid compound includes a mixer, a pulverizer, an air mill, a sand mill, or an air jet mill. This is used to subject the materials to high-speed shearing and mutual impact to achieve uniform dispersion and reduce particle size.
[0013] Preferably, in step S1, the equipment for dispersing the titanium source solid compound is a mixer, and the stirring conditions are: rotation speed 500-20000 rpm, processing time 3s-2h; and / or, in step S1, the equipment for dispersing the niobium source solid compound is an air jet mill, and the stirring conditions are: milling throughput 0.5-100Kg / h, air pressure 0.2-50Mpa.
[0014] Preferably, in step S3, the heat treatment conditions are: holding at a target temperature of 800-1300℃ for 6-48 hours, with a heating rate of 0.5-10℃ per minute.
[0015] Preferably, in step S3, the oxygen-containing atmosphere includes air, pure oxygen, or an oxygen-containing mixture.
[0016] Preferably, in step S3, the equipment used for heat treatment includes a multi-temperature zone tiltable atmosphere-protected rotary tube furnace, a split atmosphere-protected rotary tube furnace, an atmosphere rotary furnace, an atmosphere tube furnace, or an atmosphere box furnace.
[0017] Secondly, the present invention provides an application of the anion-doped Wadsley-Roth phase material prepared by the preparation method described above in the preparation of anode materials for lithium-ion batteries.
[0018] It should be noted that the anion-doped Wadsley-Roth phase material prepared according to this invention does not undergo further agglomeration during the raw material post-processing. Therefore, the anion-doped Wadsley-Roth phase material obtained after heat treatment has a complete crystal structure with few defects, uniform particle size, and good ion mobility. Consequently, this material exhibits excellent specific capacity, rate performance, and cycle performance as a negative electrode material for lithium-ion batteries. Representatively, the anion-doped Wadsley-Roth phase material prepared according to the method of this invention is micron-sized with a small specific surface area. Its particle size is very suitable for use as a negative electrode material for lithium-ion batteries, and it has the advantage of high tap density. In practical applications, it can achieve high compaction density and volumetric energy density.
[0019] Thirdly, the present invention provides a lithium-ion battery comprising a negative electrode prepared from the anion-doped Wadsley-Roth phase material.
[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The present invention uses this method to prepare anion-doped Wadsley-Roth phase materials without the participation of solvents, with almost no waste generation and no safety hazards, and the production process is green and environmentally friendly. In addition, the material mixing process is solvent-free, so no additional solvent drying process is required after the material is mixed, which can greatly save the electricity and time costs in the production process.
[0021] (2) Before mixing, the various raw materials used in the preparation of anion-doped Wadsley-Roth phase materials can be broken down into primary particle size by high-speed shearing and mutual collision between materials, so that the materials are in a fully dispersed state and achieve a uniform mixing effect.
[0022] (3) The present invention utilizes surface energy differences for mixing and stirring under solvent-free conditions, which can achieve a uniform mixing state of materials in a short time. Compared with the preparation method that involves the participation of liquid phase dispersants to disperse raw materials, it can effectively shorten the production time of materials and thus reduce production costs.
[0023] (4) The fluorine and chlorine sources selected in this invention have high melting and boiling points, which are compatible with the heat treatment temperature of the material heat treatment process.
[0024] (5) The anion-doped Wadsley-Roth phase material prepared by the present invention has a simple preparation process and the production process is easy to control; it is low in cost and suitable for large-scale production; it has excellent electrochemical performance and practical value.
[0025] In summary, this invention first disperses each solid raw material separately, then mixes them and disperses them again. This reduces agglomeration, decreases particle size, and ensures thorough dispersion and uniform mixing. The entire process is solvent-free, effectively solving the problems of complex processes, high costs, and difficulty in large-scale production associated with traditional Wadsley-Roth phase material preparation processes that require nano-sizing, porous structure design, and surface modification to achieve good electrochemical performance. Furthermore, the all-solid-phase preparation of Wadsley-Roth phase materials does not involve any solvents, thus generating no waste liquid. In addition, the Wadsley-Roth phase material prepared using the all-solid-phase method has a complete and defect-free crystal structure, uniform particle size, and good ion mobility. Therefore, this material exhibits excellent specific capacity, rate performance, and cycle performance as a lithium-ion battery anode material. Simultaneously, the Wadsley-Roth phase material prepared by this invention is micron-sized, possessing a very small specific surface area, and its particle size is ideally suited for use as a lithium-ion battery anode material, resulting in high compaction density and volumetric energy density. Attached Figure Description
[0026] Figure 1 shows the TiNb2O provided in Embodiment 1 of the present invention. 0.95 F 0.1 X-ray diffraction pattern; Figure 2 shows the TiNb2O provided in Example 1 of this invention. 0.95 F 0.1 Figure 3 is a 40,000x scanning electron microscope image of TiNb2O provided in Example 1 of this invention. 0.95 F 0.1 Figure 4 shows an 80,000x scanning electron microscope image of TiNb2O provided in Example 1 of this invention. 0.95 F 0.1 Figure 5 shows the initial charge-discharge capacity performance of the material at a 0.2C rate; Figure 5 shows the TiNb2O provided in Example 1 of this invention. 0.95 F 0.1 Rate performance diagram of electrode materials; Figure 6 shows the TiNb2O provided in Example 1 of this invention. 0.95 F 0.1 Figure 7 is a scanning electron microscope image of TiNb2O7 provided in Comparative Example 1 of the present invention at 80,000x magnification; Figure 8 is a rate performance diagram of TiNb2O7 material provided in Comparative Example 1 of the present invention. Detailed Implementation
[0027] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.
[0028] Example 1 This example provides a method for preparing anion-doped Wadsley-Roth phase material, specifically including the following steps: Weigh 132.9g of Nb2O5 raw material and place it in an air jet mill with a flow rate of 0.5Kg / h and an air pressure of 0.2Mpa to obtain uniformly dispersed Nb2O5 powder for later use.
[0029] Weigh 39.9g of TiO2 raw material and place it in a high-speed mixer. Stir at high speed for 10 minutes at a speed of 5000rpm to obtain uniformly dispersed TiO2 powder for later use.
[0030] The uniformly dispersed 132.9g Nb2O5, 39.9g TiO2, and 2.1g NaF powder with a particle size of less than 50 nm obtained by high-speed sand milling were placed in a high-speed mixer and stirred at high speed for 5 minutes at a stirring speed of 8000 rpm to obtain a uniformly mixed Nb2O5, TiO2, and NaF powder mixture.
[0031] The obtained powder mixture was placed in a tube furnace, oxygen was introduced, and the temperature was increased to 1100℃ at a rate of 2℃ / min and held for 12 hours. After natural cooling to room temperature, TiNb2O was obtained. 6.95 F 0.1 Material.
[0032] The obtained TiNb2O7 material was subjected to XRD analysis, and the results are shown in Figure 1. It can be seen from the figure that the diffraction characteristic peaks appearing in the sample are all TiNb2O. 6.95 F 0.1 The X-ray diffraction peaks indicate that the prepared TiNb2O 6.95 F 0.1 It has a single crystal phase, good crystallization, and no impurities.
[0033] The obtained TiNb2O 6.95 F 0.1 The material was characterized by SEM, and the results are shown in Figures 2 and 3. Figure 2 shows the prepared TiNb2O... 6.95 F 0.1 The material particles are uniform in size, have good crystallinity, and show no growth defects. Figure 3 shows that TiNb2O... 6.95 F 0.1The sample particles range in size from 0.5 to 1 micrometer, indicating that the material has a micrometer / submicrometer structure, which is advantageous for use as a negative electrode material in lithium-ion batteries.
[0034] Furthermore, utilizing the aforementioned TiNb2O 6.95 F 0.1 Material preparation of TiNb2O 6.95 F 0.1 The electrode sheet contains 90% active material by mass, 7% conductive agent by mass, and 3% binder by mass, with an electrode surface loading of 8.5 mg / cm². 2 The compacted density is 2.7 g / cm³. 3 Then, using this TiNb2O 6.95 F 0.1 The half-cell is fabricated using electrode sheets, specifically with a working electrode of TiNb2O. 6.95 F 0.1 It consists of lithium metal as the counter electrode and a PP separator.
[0035] The half-cell was tested, and its initial charge-discharge capacity performance at a 0.2C rate is shown in Figure 4. The figure shows that TiNb2O... 6.95 F 0.1 Within a voltage range of 1.0–3.0 V, the initial discharge capacity at a current density of 0.2 C reaches as high as 320 mAh g. -1 The initial coulomb efficiency reached 98.6% (thanks to F). - The effective rivet effect of ions is observed, and the discharge plateau is approximately 1.55V (almost consistent with the theoretical discharge voltage plateau). This indicates that the TiNb2O constructed according to this invention... 6.95 F 0.1 The material can effectively release its electrochemical properties.
[0036] The rate performance of the half-cell was tested, and the results are shown in Figure 5. As can be seen from the figure, when the battery is charged and discharged at 0.2C, its reversible specific capacity reaches 312 mAh / g, which is close to the theoretical specific capacity of the electrode material in the 1-3V voltage range. Even when the battery is charged and discharged at a high current density of 5C, its discharge capacity still reaches 194 mAh / g, with a capacity retention rate as high as 62%, and the coulombic efficiency is close to 100%. This indicates that the prepared TiNb2O 6.95 F 0.1 The material has good rate performance and can undergo high-current charge-discharge cycles.
[0037] Cyclic performance testing of the half-cell was conducted, and the results are shown in Figure 6. The figure shows that when the battery is charged and discharged at a 1C current density, its discharge specific capacity reaches 273 mAh / g after 100 cycles, with a capacity retention of 99%. This indicates that the prepared TiNb2O…6.95 F 0.1 The material has good recycling performance.
[0038] Example 2 This invention provides a method for preparing anion-doped Wadsley-Roth phase materials, specifically including the following steps: Weigh 35.6g of Nb(OH)5 and place it in a high-speed mixer, stir at high speed for 1min at a stirring speed of 20000rpm to obtain uniformly dispersed Nb(OH)5 powder for later use.
[0039] Weigh 8g of TiO2, place it in a crusher and grinder, crush and stir for 5 minutes at a stirring speed of 8000 rpm to obtain uniformly dispersed TiO2 powder for later use.
[0040] The uniformly dispersed Nb(OH)5, TiO2, and 0.58 g of NaCl powder with a particle size of less than 30 nm obtained by high-speed ball milling were placed in an air jet mill with a throughput of 100 kg / h and an air pressure of 50 MPa to obtain a uniformly mixed mixture of Nb(OH)5, TiO2, and NaCl powder.
[0041] The obtained powder mixture was placed in a rotary kiln, air was introduced, and the temperature was increased to 800℃ at a rate of 0.5℃ / min and held for 48 hours. The mixture was then allowed to cool naturally to room temperature to obtain TiNb2O. 6.95 Cl 0.1 Material.
[0042] Example 3 This invention provides a method for preparing anion-doped Wadsley-Roth phase materials, specifically including the following steps: Weigh 265.81g of Nb2O5 and place it in a crusher and grinder, stir at high speed for 3 minutes at a stirring speed of 5000rpm to obtain uniformly dispersed Nb2O5 powder for later use.
[0043] Weigh 15.97 g of TiO2 and place it in a high-speed shear pulverizer. Stir for 2 minutes at a stirring speed of 10,000 rpm to obtain uniformly dispersed TiO2 powder for later use.
[0044] The uniformly dispersed TiO2, Nb2O5 and 0.85g of LiCl powder with a particle size of less than 100nm were placed in an air jet mill with a flow rate of 10Kg / h and an air pressure of 2.5MPa to obtain a uniformly mixed mixture of TiO2, Nb2O5 and LiCl powder.
[0045] The obtained powder mixture was placed in a muffle furnace, and a nitrogen-oxygen mixture containing 20% oxygen by volume was introduced. The temperature was increased to 1300℃ at 10℃ / min and held for 6 hours. After natural cooling to room temperature, Ti2Nb was obtained. 10 O 28.95 Cl 0.1 Material.
[0046] Comparative Example 1: This invention provides a method for preparing Wadsley-Roth phase materials, specifically including the following steps: Weighing 79.8g TiO2 and 265.8g Nb2O5, adding them to deionized water and stirring for 12 hours at a stirring speed of 300 rpm to obtain a homogeneous mixed solution. After stirring, placing it in a drying oven and drying for 24 hours to obtain precursor powder.
[0047] The obtained powder was placed in a rotary kiln and heated to 1200℃ at 3℃ / min under a pure oxygen atmosphere. The temperature was held for 12 hours and then naturally cooled to room temperature to obtain TiNb2O7.
[0048] Performance testing: TiNb2O7 electrode sheets were fabricated using the above-mentioned TiNb2O7 material. The electrode sheet contained 90% active material by mass, 7% conductive agent by mass, and 3% binder by mass, with an electrode surface loading of 8.5 mg / cm². 2 The compacted density is 2.7 g / cm³. 3 Then, a half-cell was fabricated using the TiNb2O7 electrode sheet. The half-cell is specifically composed of a working electrode (TiNb2O7), a counter electrode (lithium metal), and a PP separator.
[0049] The obtained TiNb2O7 material was characterized by SEM, and the results are shown in Figure 7. Figure 7 shows that the TiNb2O7 material prepared in the comparative example has uneven particle size, with the sample particle size fluctuating widely between 0.4 and 5 micrometers. The crystal particles are interconnected, and the crystal growth interfaces are incomplete and defective. The interconnection between grains leads to dislocation of grain boundaries, hindering lithium-ion conduction in the bulk phase of the material and reducing its capacity utilization, rate performance, and long-term cycling stability.
[0050] The rate performance of the half-cell was tested, and the results are shown in Figure 8. As can be seen from the figure, when the battery is charged and discharged at a low rate of 0.2C, its discharge specific capacity is only 270 mAh / g. When the battery is charged and discharged at a high current density of 5C, its discharge specific capacity is less than 150 mAh / g. This indicates that the TiNb2O7 material prepared in Comparative Example 1 has poor rate performance and is not suitable for charge-discharge cycling at high currents.
[0051] The above embodiments are merely examples. For instance, when TiNb2O is used... 6.95 F 0.1 When fabricating electrode sheets, the mass ratio of active material in the electrode sheet can be 80-90%, the mass ratio of conductive agent can be 5-10%, the mass ratio of binder can be 5-10%, and the surface loading of the electrode sheet is 5-12 mg / cm². 2 Correspondingly, the compacted density is 2.1-3.5 g / cm³. 3The mixing speed of equipment such as mixers can be 500-20000 rpm, and the time can be 30 seconds to 2 hours (the time is negatively correlated with the mixing speed; the higher the mixing speed, the shorter the time). The throughput of air jet mills can be 0.5-100 kg / h, and the air pressure can be 0.2-50 MPa. Heat treatment of powder mixture precursors under oxygen-containing atmosphere conditions can be carried out in equipment that can fill oxygen-containing gas for high-temperature heat treatment of powders, such as multi-temperature zone tiltable atmosphere-protected rotary tube furnaces, split atmosphere-protected rotary tube furnaces, atmosphere rotary furnaces, atmosphere tube furnaces, and atmosphere box furnaces.
[0052] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for preparing anion-doped Wadsley-Roth phase materials, wherein the raw materials for preparing anion-doped Wadsley-Roth phase materials include: The titanium-based solid-phase compound, the niobium-based solid-phase compound, and the anion-based solid-phase compound are characterized by the following steps in the preparation method of the anion-doped Wadsley-Roth phase material: S1, dispersing the titanium-based solid-phase compound, the niobium-based solid-phase compound, and the anion-based solid-phase compound separately until their size is the size of primary particles, wherein the primary particle sizes of the different solid-phase compounds are different from each other; S2, mixing and dispersing the dispersed titanium-based solid-phase compound, the niobium-based solid-phase compound, and the anion-based solid-phase compound to obtain a precursor; S3, heat-treating the precursor under oxygen-containing conditions to obtain the anion-doped Wadsley-Roth phase material.
2. The preparation method according to claim 1, characterized in that, The niobium source solid-phase compound includes at least one of Nb₂O₅, Nb(OH)₅, and Nb₂O₅; and / or, the titanium source solid-phase compound includes TiO₂; and / or, the anion source solid-phase compound includes at least one of LiF, NaF, KF, NH₃F, LiCl, NaCl, KCl, and NH₃Cl.
3. The preparation method according to claim 1, characterized in that, Anion-doped Wadsley-Roth phase materials include anionic elements and oxygen elements, wherein the atomic ratio of anionic elements to oxygen elements is less than 0.
1.
4. The preparation method according to claim 1, characterized in that, In step S1, the equipment used to disperse the titanium source solid compound, the niobium source solid compound, and the anion source solid compound includes a mixer, a pulverizer, an air mill, a sand mill, or an air jet mill.
5. The preparation method according to claim 4, characterized in that, In step S1, the equipment for dispersing the titanium source solid compound is a stirrer, and the stirring conditions are: rotation speed 500-20000 rpm, processing time 3s-2h; and / or, in step S1, the equipment for dispersing the niobium source solid compound is an air jet mill, and the stirring conditions are: milling throughput 0.5-100Kg / h, air pressure 0.2-50Mpa.
6. The preparation method according to claim 1, characterized in that, In step S3, the heat treatment conditions are: holding at a target temperature of 800-1300℃ for 6-48 hours, with a heating rate of 0.5-10℃ per minute.
7. The preparation method according to claim 1, characterized in that, In step S3, the oxygen-containing atmosphere includes air, pure oxygen, or an oxygen-containing mixture.
8. The preparation method according to claim 1, characterized in that, In step S3, the equipment used for heat treatment includes a multi-temperature zone tiltable atmosphere-protected rotary tube furnace, a split atmosphere-protected rotary tube furnace, an atmosphere rotary furnace, an atmosphere tube furnace, or an atmosphere box furnace.
9. The anion-doped Wadsley-Roth phase material prepared by the preparation method according to any one of claims 1-8, and its application in the preparation of anode materials for lithium-ion batteries.
10. A lithium-ion battery, characterized in that, The negative electrode includes the anion-doped Wadsley-Roth phase material as described in any one of claims 1-8.