Sodium-ion battery layered oxide positive electrode material with multiple superlattice ordered composite structures and preparation method of sodium-ion battery layered oxide positive electrode material

Abstract

The invention discloses a sodium ion battery layered oxide positive electrode material with multiple superlattice ordered composite structures and a preparation method of the sodium ion battery layered oxide positive electrode material, two or more superlattice structures simultaneously exist in a transition metal layer of a layered oxide and are mutually compounded, namely NaxAyBzO2, 0 < x < = 1, y + z = 1, A is at least one of Na, Li, Mg, Cu, Ni, Co, Zn or vacancy (-), B is at least one of Mn, Sb, Te, Bi, Sn and Ru, and x is more than 0 and less than or equal to 1. At least three elements A and B are selected to spontaneously form at least one superlattice ordered structure, and at least two different superlattice ordered arrangement structures exist in the transition metal layer. The advantages of different superlattice structures are integrated, the anion redox reaction is effectively excited, the bulk phase structure stability of the material is enhanced, the voltage hysteresis is improved, and the rate capability of the material is effectively improved.

Description

Technical Field

[0001] The present invention belongs to the field of chemical power sources, and particularly relates to a layered oxide cathode material for sodium-ion batteries with a variety of superlattice ordered composite structures and a preparation method thereof. Background Art

[0002] With the increasingly severe energy crisis and environmental problems, the development of efficient and environmentally friendly energy storage technologies to achieve the reasonable storage and utilization of renewable new energy has become a hot issue of widespread concern. In the field of electrochemical energy storage, lithium-ion batteries are the most widely used secondary batteries at present. However, the reserves of lithium resources are limited, unevenly distributed, and the cost of lithium-ion batteries increases year by year. This hinders lithium-ion batteries from becoming large-scale electrochemical energy storage devices. In contrast, sodium-ion batteries have gradually become a research hotspot for large-scale energy storage devices in recent years due to their advantages such as rich sodium resource reserves, wide sources, and low cost.

[0003] As a crucial functional component of sodium-ion batteries, the cathode material plays a key role in improving the performance of sodium-ion batteries. Among many cathode materials, layered transition metal oxides show great commercial potential due to their high specific capacity, high ionic conductivity, and simple preparation process. Although efforts have been made to improve the electrochemical performance of layered oxide cathode materials by changing the composition and structure, quite a lot of success has been achieved. However, the redox centers of traditional layered oxide cathodes only come from transition metal (TM) ions, and the theoretical specific capacity is limited by the number of electrons that can be exchanged by TM ions per unit mass, and it is impossible to break through the theoretical capacity bottleneck.

[0004] In recent years, it has been proposed to introduce the redox of oxygen anions into layered oxides, and the redox of anionic oxygen provides extra electrons to obtain additional capacity. Among them, the superlattice structure can effectively trigger anion redox, but since most oxygen undergoes valence changes at relatively high potentials, it leads to over-oxidation of oxygen ions, further triggering irreversible lattice oxygen release and transition metal migration, accompanied by the evolution of harmful structures, and ultimately resulting in capacity / voltage decay and slow reaction kinetics. In addition, the introduction of the redox of oxygen anions into layered oxides also faces problems such as irreversible first cycle, cycle life decay, voltage hysteresis phenomenon, lattice oxygen evolution and gas production, and transition metal ion migration, which greatly limits its practical application.

[0005] CN113540440A discloses a method for constructing an ordered structure of sodium-based layered metal oxides to improve its air stability. The cathode material is sodium-based layered metal oxide Na m A x B 1-xO2, where 0.45 ≤ m ≤ 1, 0 ≤ x ≤ 1, A is a transition metal cation with a valence of +2 or +3, B is a transition metal cation with a valence of +4 or +5, the ionic radii of A and B differ by 15% - 45%, A and B are orderly arranged in the transition metal layer. The valences of A and B are different in this cathode material and there is only one valence state before charge and discharge. A, B and oxygen form a transition metal oxide layer with a certain order, making the Na ion layer in an orderly state, and there are superlattice ordered structure peaks on the XRD pattern.

[0006] CN117199337A discloses a manganese-based sodium storage cathode material with a biphasic structure, and its chemical formula is NaLi 0.2 Mn 0.8 O2, having an O3 / O'3 biphasic structure, where the O'3 phase is NaMnO2 and the O3 phase is NaLi 1 / 3 Mn 2 / 3 O2; the Li element and Mn element in the O3 phase jointly form a "honeycomb-like" superlattice ordered structure in the transition metal lamella. Two Li atoms replace two Mn atoms, forming a periodically arranged structural unit, and the repeatedly arranged structural units constitute the transition metal lamella; NaLi 1 / 3 Mn 2 / 3 O2 forms a Li-O-Na configuration.

[0007] CN110400931A discloses a manganese-based sodium storage cathode material with a superlattice ordered structure, and the chemical formula of this material is NaMn x Al 1-x O2, where x = 0.5 - 0.8, and it has a layered O3-phase crystal form. The preparation method is to mix Na2CO3, Mn2O3 and Al2O3 according to the stoichiometric ratio of NaMnxAl 1- x O2, ball mill for 15 - 20 h, then press into tablets, and then calcine at 750 - 950 °C for 12 - 20 h in an argon atmosphere. Grind the calcined product to obtain a highly stable manganese-based cathode material for sodium-ion batteries with a superlattice ordered structure.

[0008] CN108483516A discloses a lithium-ion battery cathode material with a superlattice ordered structure, which has a superlattice ordered structure on the basis of maintaining the hexagonal layered R-3m space group structure of a common layered cathode material. The molecular formula of the cathode material is Li x M1 y M2 1-y O2, where x > 0, and M1 and M2 are one or more combinations of metals such as Ni, Co, Mn, Al, Mg, Zn, Cr, V, Zr, Fe, Ti, Cu, Mo.

[0009] However, among the cathode materials obtained from the above patents, there is only one superlattice ordered structure, which has limited improvement on the cathode materials.

[0010] CN118062901A discloses a manganese-based layered oxide material with the chemical formula Na u [A x B y C z Mn 1-x-y-z O2, where u is 0.6 - 0.8, x + y + z is 0.1 - 0.5, A, B, and C are different and are respectively selected from one of Al, Li, Cu, Mg, Co, Ti, Ni, and Cr, the crystal phase of the manganese-based layered oxide contains a P2 phase and the manganese-based layered oxide has a multi-superlattice ordered structure, and the multi-superlattice ordered structure is an ordered structure composed of multiple superlattice structures.

[0011] This patent claims to obtain an ordered structure composed of multiple superlattice structures. However, through its preparation process and the characterization of the XRD of the examples. For example, the XRD pattern of the material obtained in Example 1 of this patent has two diffraction peaks near 21° and 22°. These two peaks actually correspond to a honeycomb-like superlattice ordered structure and do not count as truly multiple superlattice structures. Summary of the Invention

[0012] In order to overcome the problem that the electrochemical performance of the layered oxide cathode material with a superlattice structure in the prior art is not yet excellent enough, the purpose of the present invention is to provide a class of superlattice ordered composite structure sodium-ion battery layered oxide cathode materials and their preparation methods, which can not only trigger an anion redox reaction to increase the capacity, but also the composite superlattice structure can effectively stabilize the structural evolution occurring during the anion redox process and improve the comprehensive performance of the sodium-ion battery electrode material.

[0013] In order to achieve the above object of the invention, the present invention provides the following technical solutions:

[0014] A sodium-ion battery layered oxide cathode material with a multiple superlattice ordered composite structure, with the chemical formula Na x A y B z O2, where 0 < x ≤ 1, y + z = 1, A is at least one of Na, Li, Mg, Cu, Ni, Co, Zn, or vacancy (□), B is at least one of Mn, Sb, Te, Bi, Sn, Ru, and the total number of types of elements A and B is more than three, and the layered oxide has two or more different superlattice ordered arrangement structures.

[0015] Further, a sodium-ion battery layered oxide cathode material with a multiple superlattice ordered composite structure, with the chemical formula Na x A yB z O2, where 0.5 ≤ x ≤ 1 and 0.25 ≤ y ≤ 0.5.

[0016] Furthermore, the superlattice ordered arrangement structure includes, but is not limited to, ribbon-like, honeycomb-like, grid-like, fence-like and other superlattice ordered structures. Further still, different superlattice structures correspond to different characteristic peaks in XRD. For example, the characteristic diffraction peak angles of the honeycomb-like superlattice in XRD are at least one of 18.5 ± 0.5°, 20.5 ± 0.5°, and 22.5 ± 0.5°; those of the ribbon-like superlattice are 13.5 ± 0.5°, 20.5 ± 0.5°, 21.5 ± 0.5°, 26.5 ± 0.5°, and 29.5 ± 0.5°; those of the grid-like superlattice are 13.5 ± 0.5°, 19.5 ± 0.5°, 20.5 ± 0.5°, 28.5 ± 0.5°, and 32.5 ± 0.5°; and those of the fence-like superlattice are 17.5 ± 0.5°.

[0017] The total number of types of elements A and B is more than three, which means the total number of types of elements A and B ≥ 3; for example, Na x A1 y1 A2 y2 B z O2, Na x A y B1 z1 B2 z2 O2, Na x A1 y1 A2 y2 B1 z1 B2 z2 O2, Na x A y B1 z1 B2 z2 O2; A, A1, and A2 are independently selected from one of Na, Li, Mg, Cu, Ni, Co, Zn, or vacancy; B, B1, and B2 are independently selected from at least one of Mn, Sb, Te, Bi, Sn, Ru; y1 + y2 = y, z1 + z2 = z, and y1, y2, z1, z2 are all > 0. A, A1, A2, B, B1, B2 are different specific types of elements A and B.

[0018] In a preferred embodiment of the present invention, the sodium-ion battery layered oxide material with a multi-superlattice ordered composite structure is one of the following materials: Na 5 / 8 Li 1 / 8 Mg 1 / 8 Mn 6 / 8 O2 ribbon-like and honeycomb-like superlattice composite structure layered cathode material, Na 0.9 Li 0.1 Mg 0.1 Ni 0.2 Mn0.6 O2 honeycomb and fence-like superlattice composite structure layered cathode material, Na 5 / 8 □ 1 / 8 Mg 1 / 8 Mn 6 / 8 O2 grid and honeycomb superlattice composite structure layered cathode material, Na 5 / 8 Li 1 / 8 Ni 1 / 8 Sb 2 / 8 Mn 4 / 8 O2 fence and strip-like superlattice composite structure layered cathode material, Na 7 / 8 □ 1 / 8 Li 1 / 8 Mn 6 / 8 O2 grid and strip-like superlattice composite structure layered cathode material, Na 5 / 8 □ 1 / 8 Mg 1 / 16 Li 1 / 8 Cu 1 / 16 Ti 1 / 8 Mn 5 / 8 O2 grid, honeycomb and fence-like superlattice composite structure layered cathode material.

[0019] Preferably, in the superlattice ordered composite structure sodium ion battery layered oxide cathode material, both honeycomb and strip-like superlattice composite structures exist simultaneously; or grid-like and strip-like superlattice composite structures exist simultaneously.

[0020] The second object of the present invention is to provide a preparation method of the above superlattice ordered composite structure sodium ion battery layered oxide cathode material, comprising the following steps:

[0021] (S1) Feed a sodium source, an element A source and an element B source, mix them evenly to obtain a mixture precursor;

[0022] (S2) The mixture precursor is calcined for the first time at a first temperature, the first temperature is 800 - 1000 °C, to obtain a layered oxide with a superlattice ordered arrangement structure I;

[0023] (S3) Cool down to a second temperature for the second calcination, the second temperature is 500 - 700 °C, to obtain a layered oxide with superlattice ordered arrangement structures I and II;

[0024] Furthermore, the preparation method further comprises the following steps:

[0025] (S4) Cool down to a third temperature for the third calcination, the third temperature is 350 - 450 °C, to obtain a layered oxide with superlattice ordered arrangement structures I, II and III.

[0026] The formation of different superlattice ordered arrangement structures is mainly determined by the calcination temperature. In addition to temperature, the ordered structure of the superlattice is related to the ratio of transition metals A and B. As the A / B ratio increases, the ordered structure will show a trend from disordered - grid - strip - honeycomb, and there is a possibility of overlap between the structures. From the perspective of thermodynamics, that is, the synthesis temperature, different temperatures will promote the rearrangement of different ions to form other superlattice orderings, resulting in a layered oxide with a multi-superlattice ordered structure; by changing the material ratio, different superlattice ordered structures can be obtained.

[0027] Furthermore, during calcination, the calcination atmosphere is at least one of oxygen, air, nitrogen, and argon; the heating and cooling rate is 5 - 10 °C / min.

[0028] The present invention also provides a composite electrode, which is prepared from the following raw materials: the above-mentioned sodium-ion battery layered oxide material with a multi-superlattice ordered composite structure, a conductive additive, a binder, and a solvent.

[0029] The preparation method of the composite electrode is well-known in the art and is prepared by the technological process of pulping, coating, and drying the above raw materials.

[0030] The present invention also provides a metal-ion battery, including the above composite electrode.

[0031] Furthermore, the metal-ion battery is a sodium-ion battery, including metallic sodium as the negative electrode, the above composite electrode as the positive electrode, a separator, and an organic electrolyte.

[0032] The present invention obtains a superlattice composite structure in which two or more superlattice structures coexist in the same transition metal layer by modulating the transition metal components and selecting the superlattice synthesis temperature. The provided layered oxide cathode material for a sodium-ion battery with a lattice-ordered composite structure can not only effectively stimulate anion redox to increase capacity by integrating the characteristics of different superlattice structures, but also regulate the depth of anion redox to reduce O loss, and effectively improve the electrochemical stability during the phase change process, improve the voltage hysteresis and attenuation of the electrode material, and further optimize the electrochemical performance of the sodium-ion battery. In the layered cathode oxide material of the sodium-ion battery, the interaction between transition metal cations can cause the material to form an ordered superlattice structure under specific conditions. The formation of this ordered structure is mainly affected by the radius difference between the cations of transition metal layers A and B. Among them, when the radius difference between the two ions exceeds 15%, the trend of ordered arrangement is more significant. Different combinations of transition metal cations can form a variety of superlattice ordered structures, such as the Mg-Mn6 honeycomb structure, the vacancy-Mn6 grid structure, etc.

[0033] Furthermore, the type of the superlattice ordered structure is also affected by the ratio of transition metals A and B. As the A / B ratio increases from 0 to 1 / 2, the transition metal layer evolves from a disordered state to a superlattice structure with a higher degree of order, showing a trend such as disordered (0) - grid-like (1 / 7) - banded (1 / 4) - honeycomb-like (1 / 3 or 1 / 2). It should be noted that due to differences in stoichiometry and different synthesis conditions, there may be an overlap between these superlattice structures. Therefore, by adjusting the thermodynamic temperature during the material synthesis process, the regulation of different superlattice ordered composite structures can be achieved.

[0034] As described above, the present invention provides a method for preparing a layered cathode oxide material for a sodium-ion battery with different superlattice ordered structures by regulating the difference in the radii of transition metal cations, the cation combination, and the A / B ratio. This method has broad application prospects and significant technical advantages. Compared with the prior art, the present invention synthesizes a superlattice composite structure in which two or more superlattice structures coexist in the same transition metal layer by modulating the transition metal components and selecting the superlattice synthesis temperature, and comprehensively considering the characteristics of single-type superlattice structures, successfully obtaining a layered oxide for a sodium-ion cathode with better comprehensive electrochemical performance, and further obtaining an electrode material with better electrochemical performance. Description of the Drawings

[0035] Figure 1 XRD spectrum of the layered oxide prepared in Example 1.

[0036] Figure 2 HAADF-STEM image of the layered oxide prepared in Example 1.

[0037] Figure 3 XRD spectra of the layered oxides prepared in Example 1 and Example 5. Detailed Embodiments

[0038] The following further describes the superlattice ordered composite structure sodium-ion battery layered oxide cathode material and its preparation method according to the present invention in conjunction with specific embodiments and the drawings of the specification. The protection scope of the present invention is not limited to the following embodiments.

[0039] Unless otherwise defined, all professional terms used hereinafter have the same meaning as commonly understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the protection scope of the present invention.

[0040] Example 1

[0041] (I) Preparation of Na 5 / 8 Li 1 / 8 Mg 1 / 8 Mn6 / 8 O2 Banded and Honeycomb Superlattice Composite Structure Layered Cathode Material

[0042] (1) Weigh Na2CO3, Li2CO3, MgO and Mn3O4 according to the corresponding ratio, ball mill for 24 h, and press them into a disc with a diameter of 12 mm under a pressure of 10 MPa;

[0043] (2) Place the above-ground powder in a corundum boat and conduct the first-stage heat preservation calcination in the air atmosphere of a muffle furnace. The heating rate is 5 °C / min. After heating to 900 °C, keep it warm for 12 h. At this temperature, a Li-Mn and Mg-Mn honeycomb superlattice structure is synthesized;

[0044] (3) Change the temperature for the second-stage heat preservation calcination. The cooling rate is 5 °C / min. After cooling to 500 °C, keep it warm for 72 h. At this temperature, a Li-Mn banded superlattice structure is synthesized. After cooling to room temperature, a banded and honeycomb superlattice composite structure sodium-ion battery layered oxide cathode material is obtained;

[0045] (II) Conduct XRD testing on the Na 5 / 8 Li 1 / 8 Mg 1 / 8 Mn 6 / 8 O2 sample powder

[0046] Use an X-ray diffractometer to obtain the XRD pattern of the Na 5 / 8 Li 1 / 8 Mg 1 / 8 Mn 6 / 8 O2 sample powder, and refer to the standard PDF card to effectively analyze the material. Figure 1 This is the XRD pattern of the sample obtained in Example 1. It can be seen that the material is a typical P2-type layered oxide, and there are superlattice diffraction peaks of both banded and honeycomb structures between 10° and 30°.

[0047] Figure 2 This is the HAADF-STEM image of the layered oxide prepared in Example 1. It can be seen that there are both banded (left and right in the figure) and honeycomb (in the middle of the figure) transition metal ordered structures in the same crystal.

[0048] (III) Prepare the Na 5 / 8 Li 1 / 8 Mg 1 / 8 Mn 6 / 8 O2 composite cathode

[0049] The prepared cathode material was uniformly mixed with the conductive additive Super-P and the binder polyvinylidene fluoride (PVDF) at a mass ratio of 8:1:1, and then added to the solvent N-methylpyrrolidone (NMP). After stirring, a uniform slurry was obtained. Then, the slurry was uniformly coated on the carbon-coated aluminum foil using a 200-μm doctor blade, dried, and sliced to obtain the positive electrode sheet.

[0050] (IV) Assembling a sodium-ion battery

[0051] The composite cathode prepared above was assembled with a sodium anode to form a sodium-ion battery, and the electrolyte was a carbonate electrolyte (a solution of 1 M NaClO4 in EC / PC with a volume ratio of 1:1).

[0052] (V) Testing the sodium-ion battery

[0053] The above sodium-ion battery was tested for charge and discharge at a constant rate of 1C using a battery tester.

[0054] Example 2

[0055] (I) Preparation of Na 0.9 Li 0.1 Mg 0.1 Ni 0.2 Mn 0.6 A layered cathode material with a Na

[0056] Example 3

[0057] (I) Preparation of Na 5 / 8 □ 1 / 8 Mg 1 / 8 Mn 6 / 8 A layered cathode material with a Na

[0058] Example 4

[0059] (I) Preparation of Na 5 / 8 Li 1 / 8 Ni 1 / 8 Sb 2 / 8 Mn 4 / 8 A layered cathode material with a Na

[0060] Example 5

[0061] (1) Preparation of Na 7 / 8 □ 1 / 8 Li 1 / 8 Mn 6 / 8 O2 grid-like and ribbon-like superlattice composite structure layered cathode material. In step (1), the raw materials are changed to Na2CO3, Li2CO3 and Mn3O4, and calcination is carried out in an oxygen atmosphere in a tubular furnace at a first temperature of 700 °C, and the remaining steps are the same as in Example 1.

[0062] Figure 3 XRD spectra of the layered oxides prepared in Example 1 and Example 5.

[0063] Example 6

[0064] (1) Preparation of Na 5 / 8 □ 1 / 8 Mg 1 / 16 Li 1 / 8 Cu 1 / 16 Ti 1 / 8 Mn 5 / 8 O2 grid-like, honeycomb-like and fence-like superlattice composite structure layered cathode material. In step (1), the raw materials are changed to Na2CO3, Li2CO3, MgO, CuO, TiO2 and Mn3O4, and calcination is carried out in an oxygen atmosphere in a tubular furnace.

[0065] The calcination temperature for the third-stage sintering is 400 °C and kept for 72 h, and the remaining steps are the same as in Example 1.

[0066] Comparative Example 1

[0067] (1) Preparation of Na 0.6 Li 0.2 Mn 0.8 O2 ribbon-like superlattice structure layered cathode material.

[0068] (1) Weigh Na2CO3, Li2CO3 and Mn3O4 according to the corresponding ratio, ball mill for 24 h, and press into a disc with a diameter of 12 mm under a pressure of 10 MPa;

[0069] (2) Put the above-ground powder in a corundum boat, keep it calcined in a muffle furnace in an air atmosphere, the heating / cooling rate is 5 °C / min, keep it at 900 °C for 12 h, and cool it to room temperature to obtain a grid-like superlattice structure sodium-ion battery layered oxide cathode material.

[0070] The superlattice structure is related not only to the calcination temperature but also to the ratio of transition metals. For example, Li:Mn = 1:3 forms a honeycomb, and 1:4 forms a ribbon.

[0071] Comparative Example 2

[0072] (1) Preparation of Na 2 / 3 [Li 1 / 7 Mn 5 / 14 [Mg 1 / 7 Mn 5 / 14 O2 honeycomb superlattice structure layered cathode material. (The raw materials are Na2CO3, MgO, Li2CO3 and Mn3O4, and the remaining steps are the same as in Example 1.)

[0073] Comparative Example 3

[0074] (1) Preparation of Na 0.6775 Mg 0.28 Mn 0.72 O2 honeycomb superlattice structure layered cathode material. (The raw materials are Na2CO3, Li2CO3 and Mn3O4, and the remaining steps are the same as in Example 1.)

[0075] Comparative Example 4

[0076] (1) Preparation of Na 2 / 3 Ni 1 / 3 Mn 1 / 3 Ti 1 / 3 O2 transition metal disordered structure layered cathode material. (The raw materials are Na2CO3, NiO, TiO2 and Mn3O4, and the remaining steps are the same as in Example 1.)

[0077] Table 1 Comparison of the structures and electrochemical performance data of various superlattice materials

[0078]

[0079] It can be seen from the above examples that by using the high-temperature solid-phase method under different sintering conditions, through the comparison of Examples 1, 2, 3, 4, 5, 6 and Comparative Examples 1, 2, 3, 4, it is found that the present invention selects transition metal elements that form different superlattice structures and sets sintering conditions with different synthesis temperatures, and can combine two or more superlattice structures in the same lattice; while through the comparison of Comparative Examples 1, 2, 3, 4 with the examples, it is found that when only selecting transition metals that form one superlattice structure or only setting one synthesis temperature for sintering, only one superlattice / disordered structure can be obtained, and a superlattice composite structure cannot be obtained; and when cycling 100 times in the wide voltage range of 2–4.5V, the cycling stability is poor.

[0080] By selecting transition metal elements that form different superlattices and setting different sintering conditions, the present invention successfully prepares different types of superlattice ordered composite structure sodium-ion battery layered oxide cathode materials. The corresponding composite cathode preparation method is simple, the raw materials are easy to obtain, and the price is low. Therefore, the present invention can provide new insights into the optimized design of the structure of high-performance sodium-ion battery cathode layered materials and has broad application prospects.

Claims

1. A layered oxide cathode material for sodium ion batteries with multiple superlattice ordered composite structures, the chemical expression of which is Na x A y B z O2, wherein 0<x≤1, y+z=1, A is at least one of Na, Li, Mg, Cu, Ni, Co, Zn or vacancy (□), B is at least one of Mn, Sb, Te, Bi, Sn, Ru, characterized in that, The total number of types of the A and B elements is three or more, and the layered oxide has two or more different superlattice ordered arrangement structures.

2. The sodium ion battery layered oxide positive electrode material according to claim 1, characterized in that: 0.5≤x≤1, 0.25≤y≤0.

5.

3. The sodium ion battery layered oxide positive electrode material according to claim 1, characterized in that: Superlattice ordered structures include ribbon, honeycomb, grid, fence and other superlattice ordered structures; Furthermore, different superlattice structures correspond to different XRD characteristic peaks, such as the XRD characteristic diffraction peak angle of the honeycomb superlattice is at least one of 18.5±0.5°, 20.5±0.5°, and 22.5±0.5°; the band superlattice is 13.5±0.5°, 20.5±0.5°, 21.5±0.5°, 26.5±0.5°, and 29.5±0.5°; the grid superlattice is 13.5±0.5°, 19.5±0.5°, 20.5±0.5°, 28.5±0.5°, and 32.5±0.5°; the fence superlattice is 17.5±0.5°.

4. The sodium ion battery layered oxide positive electrode material according to claim 1, characterized in that: The chemical expression of layered oxide materials for sodium ion batteries is Na x A1 y1 A2 y2 B z O2、Na x A y B1 z1 B2 z2 O2、Na x A1 y1 A2 y2 B1 z1 B2 z2 O2、Na x A y B1 z1 B2 z2 O2; A, A1, A2 are independently selected from one of Na, Li, Mg, Cu, Ni, Co, Zn or vacancies; B, B1, B2 are independently selected from at least one of Mn, Sb, Te, Bi, Sn, Ru; y1+y2=y, z1+z2=z, and y1, y2, z1, z2 are all>0.

5. The sodium ion battery layered oxide positive electrode material according to claim 1, characterized in that: One of the following materials: Na 5 / 8 Li 1 / 8 Mg 1 / 8 Mn 6 / 8 O2 ribbon and honeycomb superlattice composite structure layered cathode materials, Na 0.9 Li 0.1 Mg 0.1 Ni 0.2 Mn 0.6 O2 fence-like and honeycomb superlattice composite structure layered cathode materials, Na 5 / 8 □ 1 / 8 Mg 1 / 8Mn 6 / 8 O2 grid and honeycomb superlattice composite structure layered cathode materials, Na 5 / 8 Li 1 / 8 Ni 1 / 8 Sb 2 / 8 Mn 4 / 8 O2 fence-like and ribbon-like superlattice composite structure layered cathode materials, Na 7 / 8 □ 1 / 8 Li 1 / 8 Mn 6 / 8 O2 grid and ribbon superlattice composite structure layered cathode materials, Na 5 / 8 □ 1 / 8 Mg 1 / 16 Li 1 / 8 Cu 1 / 16 Ti 1 / 8 Mn 5 / 8 O2 grid, honeycomb and fence-like superlattice composite structure layered positive electrode materials.

6. The sodium ion battery layered oxide positive electrode material according to claim 1, characterized in that: The superlattice ordered composite structure sodium ion battery layered oxide positive electrode material contains both honeycomb and band superlattice composite structures; or contains both grid and band superlattice composite structures.

7. The method for preparing the superlattice ordered composite structure sodium ion battery layered oxide positive electrode material according to any one of claims 1 to 6, characterized in that: The following steps are involved: (S1) adding a sodium source, an element A source and an element B source, mixing them uniformly to obtain a mixture precursor; (S2) calcining the precursor mixture for the first time at a first temperature, wherein the first temperature is 800-1000° C., to obtain a layered oxide having a superlattice ordered arrangement structure I; (S3) cooling to a second temperature for a second calcination, wherein the second temperature is 500-700° C., to obtain a layered oxide having superlattice ordered structures I and II; Furthermore, the preparation method further comprises the following steps: (S4) cooling to a third temperature and performing a third calcination, wherein the third temperature is 350-450° C., to obtain layered oxides with superlattice ordered structures I, II and III.

8. The preparation method according to claim 7, characterized in that: Furthermore, during calcination, the calcination atmosphere is at least one of oxygen, air, nitrogen and argon; and the heating and cooling rate is 5-10°C / min.

9. A composite electrode, characterized in that: The method is prepared from the following raw materials: the superlattice ordered composite structure sodium ion battery layered oxide positive electrode material according to any one of claims 1 to 6, a conductive additive, a binder and a solvent.

10. A metal ion battery, characterized in that: Comprising the composite electrode according to claim 9; Furthermore, the metal ion battery is a sodium ion battery, comprising metallic sodium as a negative electrode, the composite electrode as a positive electrode, a separator, and an organic electrolyte.

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