O3-type sodium-ion battery cathode material and preparation method and application thereof

Abstract

The application provides a type O3 sodium ion battery positive electrode material and a preparation method and application thereof. The chemical formula of the positive electrode material is: Na β Mg γ [Ni x Fe y Mn z Mg a X b ]O2; wherein 0.8≤β<1, 0

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of sodium ion batteries, and particularly relates to an O3-type sodium ion battery positive electrode material and a preparation method and application thereof. BACKGROUND

[0002] In the past decade, electrochemical energy storage technology is closely related to our life, and lithium ion batteries are widely used in consumer electronics and electric vehicles. However, the continuous growth of market demand leads to rapid shortage of lithium resources and rising cost, which limits the further development of lithium ion batteries and their application in large-scale energy storage. Therefore, it is crucial to find secondary batteries with lower cost and abundant resources to fill the gap in the application field of lithium ion batteries. Sodium ion batteries naturally enter the field of view of battery researchers. Sodium, as a homologous element of lithium, has very similar properties and the same working mechanism of the battery; secondly, sodium is abundant and widely distributed, which will not limit its development due to cost and regional restrictions, creating opportunities for cost reduction and large-scale energy storage. However, sodium ions have larger ionic radius and slower ion diffusion kinetics, which limits the development of sodium storage materials, so it is of great significance to develop positive electrode materials with low cost, high energy density, good cycle stability and rate performance.

[0003] O3-phase sodium nickel manganese iron layered oxide has the advantages of high initial sodium content, stable structure, strong controllability of sample ratio and easy preparation, and is considered as one of the ideal positive electrode material systems. However, low-nickel sodium nickel manganese iron positive electrode materials have serious voltage hysteresis and slow sodium ion kinetics, which limits their practical application. Element doping modification is one of the most widely used methods to improve material performance.

[0004] CN117476917A discloses a positive electrode material doped with double sites and coated with metal phosphate and a preparation method and application thereof. The positive electrode material comprises a core and a coating layer arranged on the surface of the core, the coating layer comprises at least one of AlPO4, Mg3(PO4)2 or Ca3(PO4)2, and the layered transition metal oxide core material has a general formula of Na α A β Fe x Mn y M z O2, by controlling the addition sequence of the Mg source to control different doping sites, but the co-precipitation preparation process is relatively complex and is not conducive to large-scale production. SUMMARY

[0005] The present application aims at the above-mentioned deficiencies of the prior art, and provides an O3-type sodium ion battery positive electrode material, a preparation method and application thereof.

[0006] In order to achieve the above-mentioned purpose, the present application adopts the following technical scheme:

[0007] The first object of the present application is to provide an O3-type sodium ion battery positive electrode material, the chemical formula of which is: Na β Mg γ [Ni x Fe y Mn z Mg a X b ]O2; wherein 0.8<=beta<1, 0<=gamma+a<=0.1, 0<=b<=0.1, 0.8<=x+y+z<=1, and X is at least one of Ti or Sn.

[0008] Further, the crystal structure of the O3-phase sodium ion battery positive electrode material comprises a hexagonal phase R-3m space group, and the cell parameters are a=2.91 angstrom, c=13.76 angstrom, alpha=beta=90 degrees, and gamma=120 degrees.

[0009] The second object of the present application is to provide a preparation method of the above-mentioned O3-type sodium ion battery positive electrode material, comprising the following specific steps:

[0010] S1, a solid compound containing a sodium source, a nickel source, an iron source, a manganese source, a magnesium source and a titanium source is ball-milled and mixed in a certain proportion to obtain a uniformly mixed powder;

[0011] S2, the mixed powder of S1 is tableted and then put into a muffle furnace for high-temperature calcination, and the sodium ion battery positive electrode material powder is obtained after grinding.

[0012] Further, the sodium source is one or more of sodium carbonate, sodium hydroxide, sodium acetate or sodium peroxide; the nickel source is one or more of nickel nitrate, nickel carbonate, nickel acetate, nickel hydroxide or nickel oxide; the iron source is one or more of iron nitrate, iron carbonate, iron acetate, iron hydroxide, diiron trioxide or magnetite; the manganese source is one or more of manganese nitrate, manganese carbonate, manganese acetate, manganese hydroxide, manganese oxide or manganese dioxide; the magnesium source is one or more of corresponding magnesium nitrate, magnesium carbonate, magnesium hydroxide or magnesium oxide; and the titanium source is one or more of titanium dioxide, titanium oxalate or titanium hydroxide.

[0013] Further, in step S1, a planetary ball mill is used, the ball milling grinding aid is isopropyl alcohol, ethanol or a mixture of isopropyl alcohol and ethanol, the ball milling beads are two different sizes, the mass ratio of large ball to small ball is 1:2, and the mass ratio of ball milling bead to raw material is 10:1.

[0014] Further, the ball milling bead size is 5mm and 10mm in diameter, the ball milling bead mass is 10 times the powder mass, the ball mill rotation speed is 250-400rpm, and the ball milling time is 8-10h.

[0015] Further, in step S2, the pressure applied during tabletting is 10-20MPa.

[0016] Further, the drying temperature of the drying process is 70-100℃ CAHNZ, the drying time is 10-15h, the treatment temperature of the heat treatment is 850-950℃, and the treatment time is 10-15h.

[0017] A third object of the present application is to provide a positive electrode comprising the above-mentioned O3-type sodium ion battery positive electrode material.

[0018] A fourth object of the present application is to provide a sodium ion battery comprising the above-mentioned O3-type sodium ion battery positive electrode material or the above-mentioned positive electrode.

[0019] Compared with the prior art, the present application has the following beneficial effects:

[0020] (1) The present application provides an O3-type sodium ion battery positive electrode material, the chemical formula of which is: Na β Mg γ [Ni x Fe y Mn z Mg a X b ]O2; wherein 0.8≤β<1, 0<γ+a≤0.1, 0≤b≤0.1, 0.8≤x+y+z≤1, X is at least one of Ti or Sn, sodium vacancies are introduced into the Na layer through sodium-poor component design, which helps Mg to enter both the sodium site and the transition metal site, alleviates the phase change of the material during charging and discharging, significantly improves the cycle stability and rate performance, and further alleviates the problems of existing O3-type sodium nickel manganese iron oxide, such as serious voltage hysteresis and slow sodium ion diffusion kinetics.

[0021] (2) The preparation method of the present application is simple, the O3-phase Mg double-site doped sodium ion battery positive electrode material is prepared by one-step high-temperature solid phase method, no special atmosphere protection is required, the production efficiency is high, the required raw materials are abundant in reserves, the cost is low, it is non-toxic and environmentally friendly, and it is suitable for large-scale industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 SEM and EDS spectra of Example 1;

[0023] Figure 2 XRD comparison chart of Example 1, 2 and Comparative Example 2;

[0024] Figure 3 XRD structure refinement chart of Example 1;

[0025] Figure 4 500 cycle long cycle performance test result chart of Example 1 in the voltage range of 2.0-4.0V, 1C (160mA g -1 ) current density;

[0026] Figure 5 First three cycle charge-discharge curve chart of Example 1 in the voltage range of 2.0-4.0V, 1C current density;

[0027] Figure 6 Rate performance test result chart of Example 1. DETAILED DESCRIPTION

[0028] In order to make the objects, technical solutions and advantages of the present application clearer, the embodiments of the present application are described in detail below, and the examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference signs represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0029] Example 1

[0030] The present embodiment provides a preparation method of an O3-type sodium ion battery positive electrode material (Na 0.8 Ni 0.15 Fe 0.3 Mn 0.35 Mg 0.1 Ti 0.1 O2).

[0031] The specific steps are as follows:

[0032] S1: According to the stoichiometric ratio of the design target product, 1.1129 g of Na2CO3 (5% excess), 0.2801 g of NiO, 0.5988 g of Fe2O3, 1.0058 g of MnCO3, 0.1458 g of Mg(OH)2, and 0.1997 g of TiO2 were weighed into a agate ball mill jar, and two kinds of agate milling beads were added in a ratio of 10:1 of the milling bead:raw material mass ratio and 2:1 of the small ball:large ball mass ratio. In order to improve the milling efficiency and make the mixture more uniform, a certain amount of isopropanol was added as a grinding aid. The jar was run at room temperature at a speed of 250 rpm for 8 h, with a 5 min stop every 30 min, and the rotation direction was changed. The grinding aid can also be ethanol or a mixture of isopropanol and ethanol.

[0033] S2: The slurry after ball milling was transferred to a clean petri dish and dried overnight in a 70°C forced air drying oven. The resulting powder was then pressed into a disc with a diameter of 20 mm and a thickness of 2 mm to obtain the intermediate material.

[0034] S3: The above intermediate material was placed in a muffle furnace and sintered at 900°C for 12 h, with a heating rate of 5°C / min -1 , and then cooled to room temperature with the furnace, to obtain O3-Na 0.8 Ni 0.15 Fe 0.3 Mn 0.35 Mg 0.1 Ti 0.1 O2, which was immediately transferred to an argon-filled glove box for storage.

[0035] Example 2

[0036] This example provides a O3-type sodium-ion battery cathode material Na 0.8 Ni 0.15 Fe 0.3 Mn 0.4 Mg 0.05 Ti 0.1 O2,

[0037] The specific steps are as follows:

[0038] The operation steps are the same as in Example 1, except that in step (S1) the raw material feeding ratio is changed to 1.1129 g of Na2CO3 (5% excess), 0.2801 g of NiO, 0.5988 g of Fe2O3, 1.0058 g of MnCO3, 0.0729 g of Mg(OH)2, and 0.1997 g of TiO2, and the chemical formula of the obtained cathode material is: Na 0.8 Ni 0.15 Fe 0.3 Mn 0.4 Mg 0.05 Ti0.1 O2.

[0039] Example 3

[0040] The operation steps are the same as Example 1, the difference is only that the raw material feeding ratio in step (S1) is changed to 1.1129g Na2CO3 (5% excess), 0.2801g NiO, 0.5988g Fe2O3, 1.0058g MnCO3, 0.1458g Mg(OH)2, 0.0998g TiO2, and the chemical formula of the obtained positive electrode material is: Na 0.8 Ni 0.15 Fe 0.3 Mn 0.4 Mg 0.1 Ti 0.05 O2.

[0041] Example 4

[0042] This example provides an O3-type sodium ion battery positive electrode material Na 0.8 Ni 0.15 Fe 0.3 Mn 0.4 Mg 0.05 Ti 0.1 O2

[0043] The operation steps are the same as Example 1, the difference is only that the raw material feeding ratio in step (S1) is changed to 1.2520g Na2CO3 (5% excess), 0.2801g NiO, 0.5988g Fe2O3, 1.0058g MnCO3, 0.1458g Mg(OH)2, 0.1997g TiO2, and the chemical formula of the obtained positive electrode material is: Na 0.9 Ni 0.15 Fe 0.3 Mn 0.4 Mg 0.1 Ti 0.05 O2.

[0044] Example 5

[0045] This example provides an O3-type sodium ion battery positive electrode material Na 0.8 Ni 0.15 Fe 0.3 Mn 0.35 Mg 0.1 Ti 0.09 Sn 0.0 1O2

[0046] The operation steps are the same as those in Example 1, except that in step (S1), the raw material feeding ratio is changed to 1.1129 g of Na2CO3 (5% excess), 0.2801 g of NiO, 0.5988 g of Fe2O3, 1.0058 g of MnCO3, 0.1458 g of Mg(OH)2, 0.1597 g of TiO2, and 0.1034 g of SnC2O4. The chemical formula of the obtained positive electrode material is: Na 0.8 Ni 0.15 Fe 0.3 Mn 0.35 Mg 0.1 Ti 0.09 Sn 0.01 O2.

[0047] Example 6

[0048] This example provides an O3-type sodium-ion battery positive electrode material Na 0.8 Ni 0.15 Fe 0.3 Mn 0.35 Mg 0.1 Ti 0.08 Sn 0.0 2O2.

[0049] The operation steps are the same as those in Example 1, except that in step (S1), the raw material feeding ratio is changed to 1.1129 g of Na2CO3 (5% excess), 0.2801 g of NiO, 0.5988 g of Fe2O3, 1.0058 g of MnCO3, 0.1458 g of Mg(OH)2, 0.1597 g of TiO2, and 0.1034 g of SnC2O4. The chemical formula of the obtained positive electrode material is: Na 0.8 Ni 0.15 Fe 0.3 Mn 0.35 Mg 0.1 Ti 0.08 Sn 0.02 O2.

[0050] Example 7

[0051] This example provides an O3-type sodium-ion battery positive electrode material Na 0.8 Ni 0.15 Fe 0.3 Mn 0.35 Mg 0.1 Ti 0.08 Sn 0.0 2O2.

[0052] The operation steps are the same as those of Example 1, except that in step (S1), the raw material feeding ratio is changed to 1.1129 g of Na2CO3 (5% excess), 0.2801 g of NiO, 0.5988 g of Fe2O3, 1.0058 g of MnCO3, 0.1458 g of Mg(OH)2, 0.1398 g of TiO2, and 0.1551 g of SnC2O4. The chemical formula of the obtained positive electrode material is: Na 0.8 Ni 0.15 Fe 0.3 Mn 0.35 Mg 0.1 Ti 0.07 Sn 0.03 O2.

[0053] Comparative Example 1

[0054] The operation steps are the same as those of Example 1, except that in step (S1), the raw material feeding ratio is changed to 1.3911 g of Na2CO3 (5% excess), 0.2801 g of NiO, 0.5988 g of Fe2O3, 1.0058 g of MnCO3, 0.1458 g of Mg(OH)2, and 0.1997 g of TiO2. The chemical formula of the obtained positive electrode material is: NaNi 0.15 Fe 0.3 Mn 0.4 Mg 0.1 Ti 0.05 O2.

[0055] Comparative Example 2

[0056] The operation steps are the same as those of Example 1, except that in step (S1), the raw material feeding ratio is changed to 1.1129 g of Na2CO3 (5% excess), 0.4668 g of NiO, 0.5988 g of Fe2O3, 1.0058 g of MnCO3, and 0.1997 g of TiO2. The chemical formula of the obtained positive electrode material is: Na 0.8 Ni 0.25 Fe 0.3 Mn 0.35 Ti 0.1 O2.

[0057] In order to better illustrate the electrochemical performance of the prepared sodium ion battery positive electrode material, the applicant has conducted the following research:

[0058] Performance characterization:

[0059] Scanning electron microscope characterization: A scanning electron microscope tester produced by HITACHI Company, model SU-3500, with an acceleration voltage of 15 kV, was used to observe the morphology of the sodium ion battery electrode materials prepared in each embodiment.

[0060] X-ray diffraction (XRD) test: a D8 Focus X-ray powder diffractometer of Bruker, Germany, was used for the test, Cu-Ka was used as the radiation source, and the wavelength was A Ni filter was used, the tube current was 40 mA, the tube voltage was 40 kV, the scanning range was 5°-90°, the scanning speed was 5° / min, and the step length was 0.05°. The material was placed in a glass slide and flattened, and the glass slide was embedded in the middle of the experimental tank of the instrument for testing; the phase identification and crystal structure information were analyzed by JADE 6.0 software.

[0061] The positive electrode material of the sodium ion battery was characterized by scanning electron microscopy (SEM) and XRD, and examples 1-7 all had similar microstructure and structure. Taking example 1 as an example, referring to Figure 1 , it can be seen that the doped positive electrode material is composed of several hundred nanometers to several microns of elliptical grains, the particle size is relatively uniform, the grain surface is smooth, and there is no residual alkali attached. Moreover, the EDS results show that each element is uniformly doped.

[0062] The X-ray diffraction pattern of the positive electrode material prepared in examples 1, 2 and comparative example 2 is shown in Figure 1 , the XRD refinement results of examples 1, 2 are shown in table 1, the atomic site information of example 1 is shown in table 2, and the structure refinement diagram of XRD is shown in Figure 2 .

[0063] Table 1. Cell parameter statistics table

[0064]

[0065] Table 2. Atomic site information statistics table of example 1

[0066]

[0067] The Mg undoped sample (comparative example 2) is a P2 / O3 composite phase, and the Mg doped sample (examples 1, 2) is a pure O3 phase. In addition, with the increase of the doping ratio, the cell parameters a and b increase, indicating that Mg occupies the transition metal site, and the decrease of the cell parameter c indicates that Mg occupies the sodium site.

[0068] The ICP results are shown in table 3, and the sodium content of the samples of examples 1, 2, 3, 5, 6 and 7 (β=0.8) is lower than the designed ratio, which provides evidence for sodium site doped Mg occupying Na site.

[0069] Table 3. Statistics table of element content obtained by ICP test

[0070]

[0071]

[0072] Reference Figure 2 The XRD comparison chart before and after Mg doping and the structure refinement results can prove that Mg occupies both sodium sites and transition metal sites.

[0073] In order to better illustrate the electrochemical performance effect of the sodium ion battery positive electrode material of the present application, the applicant has also carried out the following research:

[0074] Preparation of electrode sample:

[0075] The slurry was prepared in a proportion of 7:2:1 of the mass ratio of active material, conductive agent and binder. 0.07 g of the sodium ion battery positive electrode material sample powder and 0.02 g of Ketjen black were weighed into an agate mortar, the powder was ground to mix uniformly, then 200 μL of polyvinylidene fluoride (PVDF) solution (a solution of PVDF and N-methyl pyrrolidine (NMP)) was added, the concentration of the PVDF solution was 0.05 g·mL -1 , 200-400 μL of NMP was added, and the slurry was thoroughly ground and mixed, transferred to a clean aluminum foil, and scraped into a uniform thin film with a manual coater. Then dried in a blast drying oven at 70-100°C for 1 h (NMP preliminary volatilization), transferred to a vacuum drying oven at 110-130°C for 10-15 h. Cut into Φ = 10 mm circular slices with a slicer, and finally weighed each electrode sample and transferred to a glove box for storage.

[0076] The above prepared cathode film was assembled into a battery for conventional cycle test. Metal sodium was used as the negative electrode, glass fiber membrane (GE Whatman) was used as the separator, 1.0 mol·L -1 NaClO4 / ethylene carbonate (EC) + propylene carbonate (PC) + 5% fluoroethylene carbonate (FEC) solution (EC:PC = 1:1 vol% with 5% FEC) was used as the electrolyte, and a button cell was assembled in an argon glove box. The above assembled battery was tested by a battery tester, and the test conditions were as follows: the charge and discharge voltage range was 2.0-4.0 V, and the constant current charge and discharge test was carried out at a current density of 1C.

[0077] The positive electrode materials prepared by the examples and the comparative examples were used to prepare electrode samples according to the above method, and then electrochemical performance test was carried out, and the test results are shown in Table 4.

[0078] Table 4. Discharge specific capacity and capacity retention rate after 100 cycles

[0079] Positive electrode material Discharge specific capacity (mAh g -1 ) Capacity retention rate (%) after 100 cycles Example 1 115.8 93.0 Example 2 110.8 84.7 Example 3 116.5 73.0 Example 4 124.1 83.0 Example 5 128.1 96.5 Example 6 129.2 88.4 Example 7 110.9 87.3 Comparative Example 1 132.0 80.0

[0080] The capacity retention rate is the ratio of the discharge specific capacity of 100 cycles to the discharge specific capacity of the first cycle.

[0081] From the electrochemical performance data of each example and comparative example 1 in Table 4, it can be seen that Mg double-site doping can effectively improve the long cycle performance of the positive electrode material. For example, the capacity retention rate of example 1 is 93%, while that of comparative example 1 is only 80.0%. It is worth noting that the type and content of the doping element have a great influence on the performance of the positive electrode material. The capacity retention rate of example 3, which contains a small amount of Ti, is even lower than that of comparative example 1, only 73.0%. In addition, after replacing a small amount of Ti with Sn (example 5), the specific discharge capacity increases to 128.1 mAh g -1 , and the capacity retention rate increases to 96.5%, but this replacement is not the more the better, and with the increase of the replacement ratio, the capacity retention rate decreases slightly.

[0082] Reference Figure 4 The long cycle performance of the sodium ion battery prepared in example 1 at a current density of 1C is 76.7% after 500 cycles. In combination with Figures 1-3 , it can be seen that the Mg double-site doped positive electrode material has excellent long cycle performance, which benefits from the stable O3 phase positive electrode material structure and the elimination of surface residual alkali after Mg double-site doping.

[0083] Reference Figure 5 As can be seen from the charge-discharge curve of example 1 in the figure, Mg double-site doping can effectively alleviate the complex phase change of the material during the charge-discharge process, and smooth the charge-discharge curve.

[0084] Reference Figure 6 The rate performance test of example 1 in the present application shows that Mg double-site doping can effectively improve the rate performance of the material.

[0085] The present application provides the above-mentioned O3 phase Mg double-site doped sodium ion battery positive electrode material and its preparation method and application. The contribution to the prior art is that a one-step high-temperature solid phase method with simple process is adopted, and through the design of sodium-poor components, a Mg double-site doped layered oxide positive electrode material is obtained, which significantly improves the cycle stability and rate performance of the system material.

[0086] The present application simultaneously meets the current demand for low-cost and long cycle life of positive electrode materials, and is expected to realize large-scale production.

[0087] The above-mentioned matters not covered are applicable to the prior art.

[0088] Although some specific embodiments of the present application have been described in detail by way of example with reference to the drawings, it is to be understood that the above examples are intended to be illustrative only and are not intended to limit the scope of the present application, and that various modifications and changes can be made by those skilled in the art to the particular embodiments described without departing from the spirit and scope of the present application. It is intended that the scope of the present application be limited only by the broadest interpretation of the appended claims to be accorded under 35 U.S.C. § 112.

Claims

1. An O3-type sodium-ion battery cathode material, characterized in that, The chemical formula of the O3-type sodium ion battery cathode material is: Na β Mg γ [Ni x Fe y Mn z Mg a X b ]O2; wherein 0.8≤β<1, 0<γ+a≤0.1, 0≤b≤0.1, 0.8≤x+y+z≤1, and X is at least one of Ti or Sn.

2. The O3-type sodium-ion battery cathode material of claim 1, wherein, The crystal structure of the O3-type sodium-ion battery cathode material is a hexagonal phase R-3m space group, and the cell parameters are a=b=2.94783~2.96396 Å and c=16.31870~16.33976 Å.

3. A method of preparing the O3-type sodium-ion battery cathode material of any one of claims 1-2, characterized in that, The method comprises the following specific steps: S1. A solid compound containing a sodium source, a nickel source, an iron source, a manganese source, a magnesium source, and a titanium source is ball-milled and mixed in a certain proportion, and then dried to obtain a uniformly mixed powder; S2. The mixed powder of S1 is pressed into a tablet and then placed in a muffle furnace for high-temperature calcination, and then ground to obtain a sodium-ion battery cathode material powder.

4. The production method according to claim 3, wherein The sodium source is one or more of sodium carbonate, sodium hydroxide, sodium acetate, or sodium peroxide; the nickel source is one or more of nickel nitrate, nickel carbonate, nickel acetate, nickel hydroxide, or nickel oxide; the iron source is one or more of iron nitrate, iron carbonate, iron acetate, iron hydroxide, diiron trioxide, or magnetite; the manganese source is one or more of manganese nitrate, manganese carbonate, manganese acetate, manganese hydroxide, manganese oxide, or manganese dioxide; the magnesium source is one or more of corresponding magnesium nitrate, magnesium carbonate, magnesium hydroxide, or magnesium oxide; and the titanium source is one or more of titanium dioxide, titanium oxalate, or titanium hydroxide.

5. The production method according to claim 3, wherein In step S1, a planetary ball mill is used for ball-milling and mixing, the ball-milling grinding aid is isopropyl alcohol, ethanol, or a mixture of isopropyl alcohol and ethanol, and ball-milling beads of two different sizes are used, with a large ball:small ball mass ratio of 1:

2.

6. The production method according to claim 5, characterized by, The ball-milling beads have a size of 5 mm and 10 mm in diameter, the mass of the ball-milling beads is 10 times the mass of the powder, the rotation speed of the ball mill is 250~400 rpm, and the ball-milling time is 8~10 h.

7. The production method according to claim 3, characterized by, In step S2, the pressure applied during the tablet pressing operation is 10~20 MPa.

8. The production method according to claim 3, characterized by, The drying temperature of the drying process is 70~100 ℃, and the drying time is 10~15 h; the high-temperature calcination temperature is 850~950 ℃, and the time is 10~15 h.

9. A positive electrode, characterized by comprising: An O3-type sodium-ion battery cathode material as described in claim 1 or 2.

10. A sodium-ion battery, characterized in that, The sodium-ion battery comprises a sodium-ion battery cathode material as described in any one of claims 1~2 or a cathode as described in claim 9.

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