A trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material, a preparation method and application thereof

Abstract

A trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material, a preparation method and application thereof, belong to the technical field of sodium-ion battery electrode materials, the chemical formula of the layered oxide positive electrode material is Na x Ni a Zn b Fe c Mn d Me y O2; wherein, 0.5 <= x <= 1.2, 0.1

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of sodium-ion battery electrode materials, and particularly relates to a trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material and a preparation method and application thereof. BACKGROUND

[0002] Energy is a problem that the world is currently focusing on. Due to the unsustainability of fossil energy, and the fact that the combustion products thereof can seriously damage the environment. Therefore, people pay more attention to the development and storage of clean energy. However, clean energy such as solar energy and wind energy does not have stability. In order to achieve efficient energy use, using electrochemical energy storage is the best choice, and is also the most widely used type of energy storage technology at present.

[0003] As a mature system and the most widely used type of battery, lithium-ion batteries have the advantages of high energy density and long cycle life, and are widely used in various electronic products. At the same time, with the rapid popularization of new energy vehicles driven by lithium-ion batteries and the increasingly prominent problem of lithium resource shortage, lithium-ion batteries have been unable to meet the growing demand for large-scale energy storage.

[0004] Compared with lithium-ion batteries, sodium-ion batteries have many potential advantages. They have abundant reserves, higher operating voltage, faster charging speed and better high-temperature performance. The research on sodium-ion battery layered oxides mainly focuses on the synthesis, structure regulation, and electrochemical performance optimization of the materials. In terms of synthesis, the main synthesis methods at present include solid-phase method, sol-gel method, spray pyrolysis method, etc. These synthesis methods can control the structure and morphology of the materials to some extent, and thus affect their electrochemical performance. In terms of structure regulation, through element doping, surface coating, nanostructure design, etc., the electrochemical performance of the materials can be further optimized. For example, by doping Li, Mg and other elements, the reversible capacity and cycle stability of the layered oxides can be improved; by coating the surface with carbon, metal oxides and other materials, the conductivity and interface stability of the electrode can be improved; by nanostructure design, the specific surface area and active material utilization rate of the electrode can be increased.

[0005] Although the research on sodium-ion battery layered oxides has made some progress, there are still some challenges and problems to be solved. First, the radius of sodium ions is larger, which makes their intercalation and deintercalation in the electrode material more difficult, resulting in shorter cycle life of the battery. Second, the energy density of sodium-ion batteries is lower, which means that they may be more suitable for large-scale, long-term application scenarios in energy storage applications. Therefore, future research on sodium-ion battery layered oxides will focus more on material design, preparation process, application scenarios, etc. to realize their application in the field of energy storage. SUMMARY

[0006] In view of the deficiencies in the prior art, the present application provides a kind of micro strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material and its preparation method and application, using strong metal-oxygen bond metal doping, strong metal-oxygen bond has high bond energy and high stability, can effectively stabilize layered oxide structure, compress transition metal layer spacing, only needs micro doping to play high efficiency, effectively enhance the stability of structure, prolong cycle life, as positive active material is applied to sodium-ion battery and exhibits excellent specific capacity and rate performance.

[0007] In order to achieve the above-mentioned purpose, the present application adopts the following technical solutions:

[0008] A kind of micro strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material, the chemical formula of the layered oxide positive electrode material is Na x Ni a Zn b Fe c Mn d Me y O2;x, a, b, c, d, y simultaneously satisfy 0.5≤x≤1.2, 0.1

[0009] Further, the layered oxide positive electrode material has O3 phase.

[0010] A kind of preparation method of the micro strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material, comprising the following steps:

[0011] Step one, nickel source, zinc source, iron source and manganese source are mixed according to stoichiometric ratio, after mixing uniformly, add organic solvent, stir uniformly to make it slurry, after drying, break, obtain precursor powder;

[0012] Step two, sodium source and strong metal-oxygen bond metal Me source are added to the precursor powder, after mixing uniformly according to stoichiometric ratio, under air atmosphere, sinter at 400-700 DEG C for 3-18 h, then continue to sinter at 800-1000 DEG C for 4-14 h, after cooling, the sintered product is broken and sieved, to obtain a kind of micro strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material.

[0013] Further, in step one, the organic solvent includes one or more of ethanol, methanol, ethylene glycol, ethyl acetate, N, N-dimethylformamide, dimethyl sulfoxide and acetone.

[0014] Further, in step one, the volume of the organic solvent added is 20-40% of the volume of the mixture in step one.

[0015] Further, in step two, the molar amount of the strong metal-oxygen bond metal Me source added is less than 0.1% of the total molar amount of metals in the precursor powder.

[0016] Further, in step two, the strong metal-oxygen bond metal Me source includes one of ruthenium dioxide, ruthenium trichloride, ruthenium acetate, iridium dioxide, iridium chloride, and silver oxide.

[0017] Further, in both step one and step two, the crushing process is: first, using a jaw crusher to crush large particles into small pieces, and then using a super micro pulverizer for pulverization.

[0018] Further, in step two, the crushed sintered product is sieved through 200 mesh and above.

[0019] An application of the trace strong metal-oxygen bond metal doped sodium-ion battery layered oxide positive electrode material, the trace strong metal-oxygen bond metal doped sodium-ion battery layered oxide positive electrode material is applied in a sodium-ion battery.

[0020] Compared with the prior art, the beneficial effects of the present application are:

[0021] The present application realizes the stable morphology and structure of the layered oxide positive electrode material by adjusting the morphology and structure of the layered oxide material, and adjusting the nickel content and trace strong metal-oxygen bond metal atom doping, to obtain a trace strong metal-oxygen bond metal doped sodium-ion battery layered oxide positive electrode material to meet the demand for low-cost and high-performance electrochemical energy storage. The preparation method is simple, the conditions are mild, the operation is convenient, the cost is low, the prepared positive electrode material has excellent capacity and cycle performance in a sodium-ion battery, is suitable for industrial production and popularization, and has potential application value in advanced energy storage technologies such as sodium-ion batteries. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 The trace strong metal-oxygen bond metal doped sodium-ion battery layered oxide positive electrode material Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 O2 prepared in Example 2.

[0023] Figure 2 The trace strong metal-oxygen bond metal doped sodium-ion battery layered oxide positive electrode material Na 1.01 Ni 0.1963 Zn 0.2086Fe 0.2945 Mn 0.2945 Ru 0.0006 X-ray diffraction pattern of O2, B line represents the standard phase structure of O3 phase;

[0024] Figure 3 A trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 The first circle charge-discharge curve of O2;

[0025] Figure 4 A trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 O2 capacity retention curve. DETAILED DESCRIPTION

[0026] The technical solutions in the present application will be described clearly and completely below in combination with the drawings and embodiments. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application. DETAILED DESCRIPTION

[0028] A trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material, which is denoted as Na x Ni a Zn b Fe c Mn d Me y O2, has O3 phase, has regular polycrystalline morphology, and is doped with a trace amount of strong metal-oxygen bond metal element Me. The Me is Ru, Ir or Ag. The Na x Ni a Zn b Fe c Mn d Me y O2, wherein x, a, b, c, d and y satisfy 0.5≤x≤1.2, 0.1 DETAILED DESCRIPTION TWO

[0030] A method for preparing the micro strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material according to the first detailed description, comprising the following steps:

[0031] S1, mixing a nickel source, a zinc source, an iron source and a manganese source according to a stoichiometric ratio, adding an organic solvent after uniform mixing, stirring uniformly to make it into a slurry, drying and then crushing to obtain a precursor powder;

[0032] S2, adding a sodium source and a strong metal-oxygen bond metal Me source to the precursor powder, uniformly mixing according to a stoichiometric ratio, and then performing solid-phase sintering under an air atmosphere, sintering at 400-700℃ for 3-18h, then increasing the temperature to 800-1000℃ and continuing to sinter for 4-14h, crushing and sieving the sintered product after cooling to obtain a micro strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material.

[0033] Example 1

[0034] A method for preparing a micro strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material, comprising the following steps:

[0035] Mixing 0.8mol of nickel oxide, 0.85mol of zinc oxide, 0.6mol of iron oxide and 0.4mol of manganese oxide, adding 40ml of methanol after uniform mixing, stirring uniformly to make it into a slurry, drying in a forced air drying oven at 80℃ for 12h, then using a crusher to crush at 80V for 14min to obtain a precursor powder.

[0036] Adding 2.0281mol of sodium carbonate and 0.0008mol of ruthenium dioxide to the precursor powder, uniformly mixing, then performing solid-phase sintering under an air atmosphere, increasing the temperature to a first sintering temperature of 600℃ at a rate of 3℃ / min and sintering for 6h, then increasing the temperature to 850℃ at a rate of 3℃ / min and continuing to sinter for 13h, using a crusher to crush the sintered product at 110V for 1min after cooling in the furnace, and then sieving through a 400 mesh sieve to obtain a micro strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material with a chemical formula of Na 1.01 Ni 0.1967 Zn 0.2090 Fe 0.2951 Mn 0.2951 Ru 0.0004 O2.

[0037] The electrochemical performance is shown in Table 1.

[0038] Example 2

[0039] A preparation method of a trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material, comprising the following steps:

[0040] Mix 0.8 mol of nickel oxide, 0.8 mol of zinc oxide, 0.6 mol of iron oxide and 0.4 mol of manganese oxide, add 40 ml of methanol after uniform mixing, stir uniformly to make it into a slurry, dry in a blast drying oven at 80℃ for 12 h, then use a crusher to crush at 80V for 14 min to obtain a precursor powder.

[0041] Add 2.0321 mol of sodium carbonate and 0.0012 mol of ruthenium dioxide to the precursor powder, mix uniformly, and perform solid-phase sintering under an air atmosphere, heat at a rate of 3℃ / min to a first sintering temperature of 600℃ and sinter for 6 h, then continue to sinter at 850℃ for 13 h at a rate of 3℃ / min, cool with the furnace, then use a crusher to crush the sintered product at 110V for 1 min, and then sieve through a 400 mesh sieve to obtain a trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material with a chemical formula of Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 O2.

[0042] The electron microscope results of the positive electrode material prepared in this example are shown in Figure 1 , the XRD results are shown in Figure 2 , the first charge-discharge curve of the button cell is shown in Figure 3 , the capacity retention curve is shown in Figure 4 , and the electrochemical performance is shown in Table 1.

[0043] Example 3

[0044] A preparation method of a trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material, comprising the following steps:

[0045] Mix 0.8 mol of nickel oxide, 0.85 mol of zinc oxide, 0.6 mol of iron oxide and 0.4 mol of manganese oxide, add 40 ml of methanol after uniform mixing, stir uniformly to make it into a slurry, dry in a blast drying oven at 80℃ for 12 h, then use a crusher to crush at 80V for 14 min to obtain a precursor powder.

[0046] 0.0016 mol of iridium oxide, and then performing solid-phase sintering under an air atmosphere, and then performing temperature rising at a rate of 3°C / min to a first sintering temperature of 600°C for sintering for 6 h, and then performing temperature rising at a rate of 3°C / min to 850°C for sintering for 13 h, and then performing furnace cooling, and then performing crushing of the sintered product under 110 V for 1 min using a crusher, and then performing 400-mesh sieving, to obtain a trace strong metal-oxygen-bond metal-doped sodium-ion battery layered-oxide positive electrode material with a chemical formula of Na 1.01 Ni 0.1958 Zn 0.2082 Fe 0.2939 Mn 0.2939 Ru 0.0008 O2.

[0047] Example 4

[0048] A preparation method of a trace strong metal-oxygen-bond metal-doped sodium-ion battery layered-oxide positive electrode material includes the following steps:

[0049] 0.8 mol of nickel oxide, 0.85 mol of zinc oxide, 0.6 mol of iron oxide, and 0.4 mol of manganese oxide are mixed, 40 ml of methanol is added after uniform mixing, and stirring is performed to make it into a slurry, and then drying is performed in a forced-air drying oven at 80°C for 12 h, and then crushing is performed under 80 V for 14 min using a crusher, to obtain a precursor powder.

[0050] 0.0016 mol of iridium oxide, and then performing solid-phase sintering under an air atmosphere, and then performing temperature rising at a rate of 3°C / min to a first sintering temperature of 600°C for sintering for 6 h, and then performing temperature rising at a rate of 3°C / min to 850°C for sintering for 13 h, and then performing furnace cooling, and then performing crushing of the sintered product under 110 V for 1 min using a crusher, and then performing 400-mesh sieving, to obtain a trace strong metal-oxygen-bond metal-doped sodium-ion battery layered-oxide positive electrode material with a chemical formula of Na 1.01 Ni 0.1958 Zn 0.2082 Fe 0.2939 Mn 0.2939 Ir 0.0008 O2.

[0051] Example 5

[0052] A preparation method of a trace strong metal-oxygen-bond metal-doped sodium-ion battery layered-oxide positive electrode material includes the following steps:

[0053] Mix 0.8 mol of nickel oxide, 0.85 mol of zinc oxide, 0.6 mol of iron oxide and 0.4 mol of manganese oxide, add 40 ml of methanol after mixing evenly, stir evenly to make it into a slurry, dry in a blast drying oven at 80℃ for 12h, then use a crusher to crush at 80V for 14min to obtain a precursor powder.

[0054] Add 2.0321 mol of sodium carbonate and 0.0008 mol of silver oxide to the precursor powder, mix evenly, and then perform solid-phase sintering under an air atmosphere. Increase the temperature to a first sintering temperature of 600℃ at a rate of 3℃ / min and sinter for 6h. Then increase the temperature to 850℃ at a rate of 3℃ / min and continue sintering for 13h. After cooling in the furnace, use a crusher to crush the sintered product at 110V for 1min, and then sieve through a 400 mesh sieve to obtain a trace strong metal-oxygen bond metal-doped sodium ion battery layered oxide positive electrode material with a chemical formula of Na 1.01 Ni 0.1958 Zn 0.2082 Fe 0.2939 Mn 0.2939 Ag 0.0008 O2.

[0055] The electrochemical performance is shown in Table 1.

[0056] Comparative Example 1

[0057] A method for preparing a sodium ion battery layered oxide positive electrode material, comprising the following steps:

[0058] Mix 0.8 mol of nickel oxide, 0.8 mol of zinc oxide, 0.6 mol of iron oxide and 0.4 mol of manganese oxide, add 40 ml of methanol after mixing evenly, stir evenly to make it into a slurry, dry in a blast drying oven at 80℃ for 12h, then use a crusher to crush at 80V for 14min to obtain a precursor powder.

[0059] Add 2.0 mol of sodium carbonate to the precursor powder, mix evenly, and then perform solid-phase sintering under an air atmosphere. Increase the temperature to a first sintering temperature of 600℃ at a rate of 3℃ / min and sinter for 6h. Then increase the temperature to 850℃ at a rate of 3℃ / min and continue sintering for 13h. After cooling in the furnace, use a crusher to crush the sintered product at 110V for 1min, and then sieve through a 400 mesh sieve to obtain a sodium ion battery layered oxide positive electrode material with a chemical formula of Na 1.01 Ni 0.2000 Zn 0.2000 Fe 0.3000 Mn 0.300 0O2.

[0060] The electrochemical performance is shown in Table 1.

[0061] All the above cases were tested for electrochemical performance under the same conditions: the positive electrode material obtained in Examples 1-5 and Comparative Example 1 was used as the active material, and mixed with a conductive agent (Super P) and a binder (PVDF) in a mass ratio of 78:12:10, and an appropriate amount of solvent NMP was added to adjust the solid content. After stirring in a pulp mixer, the slurry was coated on an aluminum foil, and the coated sheet was dried in an oven at 120°C for 6 hours. A sodium sheet was used as the negative electrode, glass fiber was used as the separator, and 0.5M NaClO4+0.5M NaPF6 (solvent EC:DEC=1:1 Vol%) was used as the electrolyte to assemble a coin cell in a glove box. The battery was tested in the voltage range of 2.0-4.0V, and after two weeks of 0.1C activation, the rate test and cycle performance test were carried out.

[0062] Figure 1 The X-ray diffraction pattern of the trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 The SEM image of O2. As can be seen from the figure, the prepared Na 1.0 1Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 O2 is a standard polycrystalline ball structure, and the polycrystalline ball diameter is 4.5-6.5μm.

[0063] Figure 2 The X-ray diffraction pattern of the trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 The X-ray diffraction pattern of O2. As can be seen from the figure, the prepared Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 O2 has diffraction peaks of O3 phase. In addition, in the Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006The X-ray diffraction spectrum of O2 shows that the interplanar spacing of 003 crystal face increases due to the introduction of strong metal-oxygen bond metal ions, which can promote the transmission of sodium ions.

[0064] Figure 3 The trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 O2, the first cycle curve of the assembled button cell, the first cycle charge capacity is 153.58 mAh·g -1 , and the discharge capacity is 146.95 mAh·g -1 .

[0065] Figure 4 The trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 O2, the capacity retention curve of which can be seen from the figure that after 200 cycles, the capacity retention rate is 95.4%.

[0066] As can be seen, the trace strong metal-oxygen bond metal-doped sodium-ion battery layered oxide positive electrode material Na 1.01 Ni 0.1963 Zn 0.2086 Fe 0.2945 Mn 0.2945 Ru 0.0006 O2 in the sodium-ion battery exhibits excellent cycle capacity and cycle stability. The present application provides a new way to adjust the structure and performance of the sodium-ion battery layered oxide positive electrode, and promotes the application of layered oxides in the energy storage field. The preparation process of the present application is simple, the reaction conditions are mild, the operation is convenient, the cost is low, and it is suitable for industrial production.

[0067] Table 1

[0068]

[0069] In addition, it should be understood that although the present specification is described in terms of embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can be combined appropriately to form other embodiments that those skilled in the art can understand.

Claims

1. A micro-supercritical metal-oxygen bonded metal doped sodium-ion battery layered oxide cathode material, characterized by: The chemical formula of the layered oxide positive electrode material is Na x Ni a Zn b Fe c Mn d Me y O2; x, a, b, c, d, y simultaneously satisfy 0.5≤x≤1.2, 0.1 The layered oxide positive electrode material has an O3 phase.

2. A method of preparing the micro-supersized metal-oxygen bonded metal doped sodium-ion battery layered oxide cathode material of claim 1, characterized in that, The method comprises the following steps: Step one, mix the nickel source, zinc source, iron source and manganese source according to the stoichiometric ratio, add the organic solvent after mixing uniformly, stir uniformly to make it into a slurry, dry and crush to obtain the precursor powder; Step two, add the sodium source and strong metal-oxygen bond metal Me source to the precursor powder, mix uniformly according to the stoichiometric ratio, sinter at 400-700℃ for 3-18h under air atmosphere, then continue to sinter at 800-1000℃ for 4-14h, crush and sieve the sintered product after cooling to obtain a trace strong metal-oxygen bond metal doped sodium ion battery layered oxide positive electrode material.

3. The method of claim 2, wherein: In step one, the organic solvent includes one or more of ethanol, methanol, ethylene glycol, ethyl acetate, N,N-dimethylformamide, dimethyl sulfoxide and acetone.

4. The method of claim 2, wherein: In step one, the volume of the added organic solvent is 20%-40% of the volume of the mixture in step one.

5. The method of claim 2, wherein: In step two, the molar amount of the added strong metal-oxygen bond metal Me source is less than 0.1% of the total molar amount of metals in the precursor powder.

6. The method of claim 2, wherein: In step two, the strong metal-oxygen bond metal Me source includes one of iridium dioxide, iridium chloride and silver oxide.

7. The method of claim 2, wherein: In step one and step two, the crushing process is as follows: first, use a crusher to crush large particles into small pieces, and then use a super micro pulverizer to crush.

8. The method of claim 2, wherein: In step two, the crushed sintered product is sieved through a 200-mesh sieve or a finer sieve.

9. Use of the micro-supersized metal-oxygen bonded metal doped sodium-ion battery layered oxide cathode material of claim 1, characterized by: The trace strong metal-oxygen bond metal doped sodium ion battery layered oxide positive electrode material is applied to a sodium ion battery.

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