Sodium-ion battery positive electrode material as well as preparation method and application thereof
By doping nano-TiO2 and anhydrous sodium carbonate into the cathode material of sodium-ion batteries, the interlayer spacing of the O3 phase is increased, which solves the problems of irreversible structural phase transition and high diffusion barrier of the cathode material of sodium-ion batteries, and achieves better charge-discharge cycle stability and electrochemical performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-25
- Publication Date
- 2026-04-10
AI Technical Summary
Existing commercial sodium-ion battery cathode materials using O3-phase layered transition metal oxides suffer from irreversible structural phase transitions during charge-discharge cycles and high sodium-ion diffusion barriers.
The preparation method involves uniformly coating the precursor powder surface with nano-TiO2 powder, anhydrous sodium carbonate, and sodium oxalate. After ball milling and calcination, Ti doping is achieved, which increases the interlayer spacing of the O3 phase, reduces the diffusion barrier of sodium ions, and releases carbon dioxide through calcination to increase porosity, providing a convenient channel for sodium ion transport. Combined with morphology control agents and freeze-drying, the uniformity and structural density of the material are improved.
It improves the charge-discharge cycle stability and electrochemical performance of sodium-ion battery cathode materials, reduces the sodium-ion diffusion barrier, enhances the mechanical strength of the materials, suppresses the irreversible phase transition of the O3 phase, and improves the charge-discharge cycle stability and conductivity of the battery.
Smart Images
Figure CN121839616A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of battery materials technology, and in particular to a sodium-ion battery cathode material, its preparation method, and its application. Background Technology
[0002] In recent years, sodium-ion secondary batteries (SIBs) have gradually become a research focus. The cathode material is one of the key factors determining the performance of SIBs and is crucial for the commercialization of high-performance SIBs. O3-phase layered transition metal oxides have unique advantages in energy density, operating voltage, and synthesis cost, making them the most promising commercial sodium-ion cathode materials. However, O3-phase layered transition metal oxide materials still suffer from significant drawbacks in practical applications, including irreversible structural phase transitions during charge-discharge cycles, high sodium-ion diffusion barriers, and poor air stability.
[0003] Therefore, it is necessary to provide a sodium-ion battery cathode material, its preparation method, and its application to solve the problems of irreversible structural phase transition and high sodium-ion diffusion barrier in existing commercial sodium-ion cathode materials that use O3-phase layered transition metal oxides during charge-discharge cycles. Summary of the Invention
[0004] The purpose of this invention is to provide a sodium-ion battery cathode material, its preparation method, and its application. The specific technical solution is as follows: In a first aspect, the present invention provides a method for preparing a sodium-ion battery cathode material, comprising: Step S1: Under sealed and stirring conditions, an alkaline precipitant is added dropwise to a mixed salt solution, followed by the addition of an auxiliary complexing agent and a morphology control agent to obtain a reaction system; the reaction system is then subjected to ultrasonic treatment and followed by heating and stirring to obtain a precipitate mixture; wherein the solutes used in the mixed salt solution include nickel salt, manganese salt and cobalt salt; Step S2: The precipitate mixture is centrifuged to obtain a coarse precipitate; the coarse precipitate is washed and centrifuged to obtain a precipitate. Step S3: The precipitate is freeze-dried to obtain precursor powder; Step S4: The precursor powder, nano TiO2 powder, anhydrous sodium carbonate and sodium oxalate are mixed in a mass ratio of 1:0.03:0.6:0.4 and then subjected to ball milling, sieving, pressing and calcination in sequence to obtain sodium-ion battery cathode material.
[0005] Optionally, in step S1, the alkaline precipitant is prepared by mixing alkaline solution and ammonia water at a volume ratio of 2 to 4:1. The ammonia solution in question is 99% pure ammonia monohydrate. The steps for obtaining the alkaline solution include: mixing alkaline sodium salt with hot water under an inert atmosphere, and then stirring to dissolve the mixture to obtain the alkaline solution; the molar concentration of the alkaline solution is 0.25~1.5 mol / L; The alkaline sodium salt includes any one of sodium acetate, sodium oxalate, sodium carbonate, sodium nitrate, sodium bicarbonate, and sodium hydroxide. The alkaline precipitant is added to the mixed salt solution at a rate of 0.5~1.5 mL / min.
[0006] Optionally, in step S1, the mass ratio of the nickel salt, the manganese salt, and the cobalt salt in the mixed salt solution is 25~100:10~25:10~25; The nickel salt includes nickel sulfate; the manganese salt includes manganese sulfate; the cobalt salt includes cobalt sulfate; The auxiliary complexing agent includes sodium citrate; The morphology control agent includes polyethylene glycol-1000; In the reaction system, the mass ratio of the alkaline precipitant to the mixed salt solution is 0.3:1; The molar concentration of the auxiliary complexing agent in the reaction system is 0.05~0.1 mol / L; The morphology control agent has a mass concentration of 0.5~1.0 g / L in the reaction system.
[0007] Optionally, in step S1, the ultrasonic power used in the ultrasonic treatment is 300W and the ultrasonic time is 10min. The heating and stirring process used is a heating temperature of 60±2℃, a stirring rate of 50~100r / min, and a heating and stirring time of 10~12h. Step S1 further includes adjusting the pH of the reaction system to 11.0~11.5; Optionally, in step S2, the centrifugation process uses a centrifugation rate of 5000~6000 r / min and a centrifugation time of 5~8 min; the washing and centrifugation process includes washing the coarse precipitate with water first, then washing it with alcohol, and then centrifuging the coarse precipitate after both the water washing and alcohol washing processes.
[0008] Optionally, in step S3, the freeze-drying process is carried out at a temperature of -40°C for 12 hours.
[0009] Optionally, in step S4, the ball milling process is completed under an inert atmosphere, with a ball-to-material ratio of 8:1 to 10:1, a ball milling rate of 400 to 500 r / min, and a ball milling time of 10 to 12 h. The sieving process involves passing the ball-milled powder through a 200-mesh sieve and collecting the powder that has passed through the sieve.
[0010] Optionally, the pressing pressure used in the tableting process is 10~15MPa, and the pressing time is 1h; the diameter of the pressed blank is 10~15mm, and the thickness is 1~2mm. The calcination process includes a first calcination, a second calcination, and a cooling process performed sequentially. The first calcination temperature is 350~400℃, and the holding time is 1~2h; the heating rate used to raise the temperature to the first calcination temperature in the first calcination process is 2~3℃ / min; The second calcination temperature is 750~850℃, and the holding time is 4~6h; the heating rate used to raise the temperature to the second calcination temperature in the second calcination process is 5~8℃ / min; The cooling process employs a cooling rate of 10~15℃ / min, which cools the second calcination temperature down to room temperature.
[0011] In a second aspect, the present invention provides a sodium-ion battery cathode material, which is prepared by the aforementioned method for preparing sodium-ion battery cathode materials; the particle size of the sodium-ion battery cathode material is 10~20μm. The sodium-ion battery cathode material comprises the following components by mass percentage: nickel 20%~60%, titanium 0.1%~10%, cobalt 0.1%~15%, manganese 0.1%~15%, oxygen 10%~20%, and sodium 0.1%~20%.
[0012] In a third aspect, the present invention provides the application of the aforementioned sodium-ion battery cathode material in sodium-ion secondary batteries.
[0013] The application of the technical solution of the present invention has at least the following beneficial effects: This invention provides a method for preparing a sodium-ion battery cathode material. The prepared cathode material involves ball milling to uniformly coat the surface of a precursor powder with nano-TiO2 powder, anhydrous sodium carbonate, and sodium oxalate. Following calcination, Ti doping is achieved in the cathode material, increasing the interlayer spacing of the O3 phase. This facilitates sodium ion insertion and extraction, lowers the sodium ion diffusion barrier, and improves the sodium ion transport rate. The calcination of anhydrous sodium carbonate and sodium oxalate releases carbon dioxide, increasing the porosity of the cathode material and providing a convenient channel for sodium ion transport, resulting in better electrochemical performance and ionic conductivity. Ti doping also increases the interlayer spacing of the O3 phase, enhancing mechanical strength and helping to suppress irreversible phase transitions in the O3 phase, maintaining its integrity and improving the charge-discharge cycle stability of the cathode material. Therefore, this invention solves the problems of irreversible structural phase transitions and high sodium ion diffusion barriers in existing commercially available sodium-ion cathode materials using layered transition metal oxides with an O3 phase during charge-discharge cycles. Furthermore, the morphology control agent used in step S1 facilitates the control of the precursor grain size to be fine and uniform, which is conducive to improving the material's electrical conductivity; the freeze-drying treatment used in step S3 can prevent the material from dehydrating, oxidizing, hardening, and agglomerating, which is conducive to forming uniformly dispersed and fine precursor powder particles; the sieving treatment used in step S4 facilitates the obtaining of powder particles with uniform particle size; and the tableting treatment used in step S4 facilitates the improvement of the material's dense structure, thereby improving the calcination efficiency.
[0014] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description
[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.
[0016] Figure 1 This is a scanning electron microscope (SEM) image of the sodium-ion battery cathode material prepared in Example 1.
[0017] Figure 2 This is a scanning electron microscope (SEM) image of the precursor powder prepared in Example 1.
[0018] Figure 3 This is the X-ray crystal diffraction (XRD) pattern of the precursor powder and sodium-ion battery cathode material prepared in Example 1.
[0019] Figure 4 This is a cycle performance diagram of the sodium-ion secondary battery prepared in Example 1 under a 1C discharge rate.
[0020] Figure 5 This is a graph showing the cycle performance of the sodium-ion secondary battery prepared in Comparative Example 1 under a 1C discharge rate.
[0021] Figure 6 This is a TESCAN scanning electron microscope image of the sodium-ion battery cathode material prepared in Example 1.
[0022] Figure 7 yes Figure 6 The energy spectrum read by the TESCAN scanning electron microscope. Detailed Implementation
[0023] 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 a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.
[0024] Example 1: A method for preparing a sodium-ion battery cathode material includes: Step S1: Under sealed and stirring conditions, an alkaline precipitant is added dropwise to a mixed salt solution, followed by the addition of an auxiliary complexing agent and a morphology control agent to obtain a reaction system; the reaction system is then subjected to ultrasonic treatment and followed by heating and stirring to obtain a precipitate mixture; wherein the solutes used in the mixed salt solution include nickel salt, manganese salt and cobalt salt; Step S2: The precipitate mixture is centrifuged to obtain a coarse precipitate; the coarse precipitate is washed and centrifuged to obtain a precipitate. Step S3: The precipitate is freeze-dried to obtain precursor powder; Step S4: The precursor powder, nano TiO2 powder, anhydrous sodium carbonate and sodium oxalate are mixed in a mass ratio of 1:0.03:0.6:0.4 and then subjected to ball milling, sieving, pressing and calcination in sequence to obtain sodium-ion battery cathode material.
[0025] In step S1, the alkaline precipitant is prepared by mixing alkaline solution and ammonia water at a volume ratio of 4:1. The ammonia solution in question is 99% pure ammonia monohydrate. The steps for obtaining the alkaline solution include: mixing alkaline sodium salt (specifically 12g sodium hydroxide) with hot water (specifically 200mL distilled water at a temperature of 30~40℃) under an inert atmosphere, and then stirring to dissolve the mixture to obtain the alkaline solution; the molar concentration of the alkaline solution is 1.5mol / L; The alkaline precipitant is added to the mixed salt solution at a rate of 0.5 mL / min.
[0026] In step S1, the mass ratio of the nickel salt (specifically 19.75 g nickel sulfate hexahydrate), the manganese salt (specifically 4.25 g manganese sulfate monohydrate), and the cobalt salt (specifically 7.05 g cobalt sulfate heptahydrate) in the mixed salt solution is 46.5:10:16.6. In the reaction system, the mass ratio of the alkaline precipitant to the mixed salt solution is 0.3:1; The auxiliary complexing agent is sodium citrate, and its molar concentration in the reaction system is 0.05~0.1 mol / L (specifically 0.1 mol / L). The morphology control agent is polyethylene glycol-1000, and its mass concentration in the reaction system is 0.5~1.0 g / L (specifically 1.0 g / L).
[0027] In step S1, the ultrasonic power used in the ultrasonic treatment is 300W and the ultrasonic time is 10min. The heating and stirring process used a heating temperature of 60℃, a stirring rate of 60r / min, and a heating and stirring time of 12h. Step S1 further includes adjusting the pH of the reaction system to 11.0~11.5 (specifically 11.0). In step S2, the centrifugation process uses a centrifugation rate of 5000 r / min and a centrifugation time of 5-8 min (specifically 5 min); the washing and centrifugation process includes washing the coarse precipitate with water first, then washing it with alcohol, and then centrifuging the coarse precipitate after both the water washing and alcohol washing processes.
[0028] In step S3, the freeze-drying process is carried out at a temperature of -40°C for 12 hours.
[0029] In step S4, the ball milling process is completed under an inert atmosphere, with a ball-to-material ratio of 8:1 to 10:1 (specifically 8:1), a ball milling rate of 500 r / min, and a ball milling time of 12 h. The sieving process involves passing the ball-milled powder through a 200-mesh sieve and collecting the powder that has passed through the sieve.
[0030] The tableting process uses a pressing pressure of 10~15MPa (specifically 10MPa) and a pressing time of 1h; the diameter of the pressed blank is 10~15mm and the thickness is 1~2mm, and the specific dimensions of the blank are determined by the mold. The calcination process includes a first calcination, a second calcination, and a cooling process performed sequentially. The first calcination temperature is 350~400℃ (specifically 400℃), and the holding time is 1~2h (specifically 2h); the heating rate used to raise the temperature to the first calcination temperature in the first calcination process is 2~3℃ / min (specifically 2℃ / min). The second calcination temperature is 750~850℃ (specifically 800℃), and the holding time is 4~6h (specifically 6h); the heating rate used to raise the temperature to the second calcination temperature in the second calcination process is 5~8℃ / min (specifically 5℃ / min). The cooling process employs a cooling rate of 10~15℃ / min (specifically 10℃ / min) to cool the second calcination temperature down to room temperature.
[0031] Samples of the sodium-ion battery cathode material prepared in steps S1-S4 of Example 1 were taken and observed using a scanning electron microscope. Figure 1 It is known that the surface of the sodium-ion battery cathode material prepared in Example 1 exhibits a lamellar granular structure with a radius of approximately 5-10 μm.
[0032] The precursor powders prepared in steps S1-S3 of Example 1 were sampled and observed using a scanning electron microscope. Figure 2 It is known that the precursor powder prepared in Example 1 has spherical particles with a diameter of 20~30μm, and the surface of the precursor powder is covered with a large number of granular and lamellar structures.
[0033] Samples of the precursor powder and sodium-ion battery cathode material prepared in Example 1 were taken and subjected to X-ray crystal diffraction analysis. Figure 3 It is known that there are multiple obvious characteristic peaks in the spectrum of the precursor powder prepared in Example 1, which are located on the (001), (100) and (011) crystal planes, respectively, indicating that the Ni-based ternary precursor was successfully prepared; in the spectrum of the sodium-ion battery cathode material prepared in Example 1, two obvious diffraction peaks can be observed, which are located at about 37° and 43°, respectively. These two peaks correspond to the (111) and (200) crystal planes of TiO2, indicating that Ti doping was successful.
[0034] See Figure 6 and Figure 7Chemical composition analysis (using a TESCAN scanning electron microscope with energy dispersive spectroscopy) revealed that the sodium-ion battery cathode material prepared in Example 1 consisted of the following components by mass percentage: nickel 36.05%, titanium 1.94%, cobalt 14.44%, manganese 14.29%, oxygen 17.18%, and sodium 16.1%. Furthermore, from... Figure 6 It is known that the particle size of the sodium-ion battery cathode material prepared in Example 1 is approximately 10 μm. Among them, in Figure 6 Titanium is not listed because its content is relatively low, and its content is within... Figure 7 The figure is 1.94%.
[0035] The application of the sodium-ion battery cathode material prepared in Example 1 in sodium-ion secondary batteries is carried out according to the following steps: 1) Dry 1g of sodium-ion battery positive electrode material in a vacuum oven at 60°C for 24 hours, then transfer it to a glove box. Mix 0.14g of sodium-ion battery positive electrode material, 0.04g of acetylene black, and 0.02g of polyvinylidene fluoride (PVDF) material, grind thoroughly, pour into a 2mL volumetric flask, add 1mL of N-methylpyrrolidone (NMP) solution, and stir for 6 hours to form a uniform slurry. Coat the slurry onto the surface of aluminum foil, dry it in a vacuum oven at 50°C for 24 hours, and then cut it into circular positive electrode sheets with a diameter of 10mm for later use. 2) Electrochemical characterization was performed using a 2032 coin-type half-cell in an anhydrous and oxygen-free atmosphere within a glove box. The electrolyte solution consisted of propylene carbonate (PC), fluoroethylene carbonate (FEC) (volume ratio 98:2), and sodium hexafluorophosphate (NaPF6). After placing two 16mm diameter glass fiber membranes, 20μL of electrolyte was added to both the positive and negative electrode sides. A 10mm diameter circular positive electrode was then placed, along with a gasket and spring, and finally the negative electrode shell was installed. The assembly was then hydraulically pumped to form a sodium-ion secondary battery. The assembled battery was allowed to stand for 12 hours before electrochemical testing. The test results are as follows: Figure 4 As shown.
[0036] Figure 4 This is a cycle performance graph of the sodium-ion secondary battery prepared in Example 1 under a 1C discharge rate. From... Figure 4 As can be seen, the sodium-ion secondary battery exhibits an initial discharge specific capacity of 130 mAh / g under a 1C discharge rate, and retains a discharge specific capacity of 80 mAh / g after 600 cycles, with a capacity retention rate of 61.5%. This excellent capacity retention is closely related to the improved mechanical strength of the O3-type layered oxide due to titanium doping, which suppresses the irreversible transformation of the O3 phase during charge-discharge cycling and enhances battery reaction kinetics.
[0037] Comparative Example 1: Unlike Example 1, the 25g of anhydrous sodium carbonate in step S4 was replaced with 14g of sodium hydroxide.
[0038] The application of the sodium-ion battery cathode material prepared by Comparative Example 1 in sodium-ion secondary batteries follows the same application steps as in Example 1.
[0039] Figure 5 The graph shows the cycle performance of the sodium-ion secondary battery prepared in Comparative Example 1 under a 1C discharge rate. From... Figure 5 As can be seen, the sodium-ion secondary battery has an initial discharge specific capacity of 149 mAh / g under a 1C discharge rate, and after 250 cycles, its discharge specific capacity is 80 mAh / g, with a capacity retention rate of 53.7%.
[0040] A comparison of Example 1 and Comparative Example 1 shows that the sodium-ion battery cathode material prepared using Example 1 of this invention exhibits better charge-discharge cycle stability. This is because, in Example 1 of this invention, nano-TiO2 powder, anhydrous sodium carbonate, and sodium oxalate are uniformly coated onto the surface of the precursor powder through ball milling. Then, after calcination, Ti doping is achieved in the sodium-ion battery cathode material, thereby increasing the spacing between the O3 phase layers. This facilitates the insertion and extraction of sodium ions, reduces the sodium ion diffusion barrier, and improves the sodium ion transport rate. Furthermore, the calcination of anhydrous sodium carbonate and sodium oxalate releases carbon dioxide, increasing the porosity of the sodium-ion battery cathode material and providing a convenient channel for sodium ion transport, resulting in better electrochemical performance and ionic conductivity. Ti doping also increases the spacing between the O3 phase layers, enhancing mechanical strength and helping to suppress irreversible phase transitions of the O3 phase, maintaining the integrity of the O3 phase, and thus improving the charge-discharge cycle stability of the sodium-ion battery cathode material. The combination of nano-TiO2 powder, anhydrous sodium carbonate, and sodium oxalate can synergistically improve the charge-discharge cycle stability of sodium-ion battery cathode materials.
[0041] The above description is only a preferred embodiment of the present invention and does not limit the scope of the present invention. All equivalent structural transformations made under the inventive concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the protection scope of the present invention.
Claims
1. A method for preparing a sodium-ion battery cathode material, characterized in that, include: Step S1: Under sealed and stirring conditions, an alkaline precipitant is added dropwise to a mixed salt solution, followed by the addition of an auxiliary complexing agent and a morphology control agent to obtain a reaction system; the reaction system is then subjected to ultrasonic treatment and followed by heating and stirring to obtain a precipitate mixture; wherein the solutes used in the mixed salt solution include nickel salt, manganese salt and cobalt salt; Step S2: The precipitate mixture is centrifuged to obtain a coarse precipitate; the coarse precipitate is washed and centrifuged to obtain a precipitate. Step S3: The precipitate is freeze-dried to obtain precursor powder; Step S4: The precursor powder, nano TiO2 powder, anhydrous sodium carbonate and sodium oxalate are mixed in a mass ratio of 1:0.03:0.6:0.4 and then subjected to ball milling, sieving, pressing and calcination in sequence to obtain sodium-ion battery cathode material.
2. The method for preparing the sodium-ion battery cathode material as described in claim 1, characterized in that, In step S1, the alkaline precipitant is prepared by mixing alkaline solution and ammonia water at a volume ratio of 2 to 4:
1. The ammonia solution in question is 99% pure ammonia monohydrate. The steps for obtaining the alkaline solution include: mixing alkaline sodium salt with hot water under an inert atmosphere, and then stirring to dissolve the mixture to obtain the alkaline solution; the molar concentration of the alkaline solution is 0.25~1.5 mol / L; The alkaline sodium salt includes any one of sodium acetate, sodium oxalate, sodium carbonate, sodium nitrate, sodium bicarbonate, and sodium hydroxide. The alkaline precipitant is added to the mixed salt solution at a rate of 0.5~1.5 mL / min.
3. The method for preparing the sodium-ion battery cathode material as described in claim 1, characterized in that, In step S1, the mass ratio of the nickel salt, the manganese salt, and the cobalt salt in the mixed salt solution is 25~100:10~25:10~25; The nickel salt includes nickel sulfate; the manganese salt includes manganese sulfate; the cobalt salt includes cobalt sulfate; The auxiliary complexing agent includes sodium citrate; The morphology control agent includes polyethylene glycol-1000; In the reaction system, the mass ratio of the alkaline precipitant to the mixed salt solution is 0.3:1; The molar concentration of the auxiliary complexing agent in the reaction system is 0.05~0.1 mol / L; The morphology control agent has a mass concentration of 0.5~1.0 g / L in the reaction system.
4. The method for preparing the sodium-ion battery cathode material as described in claim 1, characterized in that, In step S1, the ultrasonic power used in the ultrasonic treatment is 300W and the ultrasonic time is 10min. The heating and stirring process uses a heating temperature of 60±2℃, a stirring rate of 50~100r / min, and a heating and stirring time of 10~12h. Step S1 further includes adjusting the pH of the reaction system to 11.0~11.
5.
5. The method for preparing the sodium-ion battery cathode material as described in claim 1, characterized in that, In step S2, the centrifugation process uses a centrifugation rate of 5000~6000 r / min and a centrifugation time of 5~8 min; the washing and centrifugation process includes washing the coarse precipitate with water first, then washing it with alcohol, and then centrifuging the coarse precipitate after both the water washing and alcohol washing processes.
6. The method for preparing the sodium-ion battery cathode material as described in claim 1, characterized in that, In step S3, the freeze-drying process is carried out at a temperature of -40°C for 12 hours.
7. The method for preparing the sodium-ion battery cathode material as described in claim 1, characterized in that, In step S4, the ball milling process is completed under an inert atmosphere, with a ball-to-material ratio of 8:1 to 10:1, a ball milling rate of 400 to 500 r / min, and a ball milling time of 10 to 12 h. The sieving process involves passing the ball-milled powder through a 200-mesh sieve and collecting the powder that has passed through the sieve.
8. The method for preparing the sodium-ion battery cathode material as described in claim 1, characterized in that, The tableting process uses a pressing pressure of 10-15 MPa and a pressing time of 1 hour; the diameter of the pressed blank is 10-15 mm and the thickness is 1-2 mm. The calcination process includes a first calcination, a second calcination, and a cooling process performed sequentially. The first calcination temperature is 350~400℃, and the holding time is 1~2h; the heating rate used to raise the temperature to the first calcination temperature in the first calcination process is 2~3℃ / min; The second calcination temperature is 750~850℃, and the holding time is 4~6h; the heating rate used to raise the temperature to the second calcination temperature in the second calcination process is 5~8℃ / min; The cooling process employs a cooling rate of 10~15℃ / min, which cools the second calcination temperature down to room temperature.
9. A sodium-ion battery cathode material, characterized in that, The sodium-ion battery cathode material is prepared by the preparation method of any one of claims 1 to 8; the particle size of the sodium-ion battery cathode material is 10 to 20 μm. The sodium-ion battery cathode material comprises the following components by mass percentage: nickel 20%~60%, titanium 0.1%~10%, cobalt 0.1%~15%, manganese 0.1%~15%, oxygen 10%~20%, and sodium 0.1%~20%.
10. The application of the sodium-ion battery cathode material as described in claim 9 in sodium-ion secondary batteries.