Method for manufacturing an anion-cation co-doped high-entropy sodium-ion battery cathode material

Abstract

The application discloses a manufacturing method of a positive electrode material of a sodium-ion battery with co-doped anions and cations, and belongs to the technical field of sodium-ion secondary battery materials, in particular to a manufacturing method of a positive electrode composite oxide material, which comprises the following steps: mixing inorganic metal compounds, and then performing a crushing treatment; mixing the crushed particles with organic metal compounds and water, and performing ball milling; adding phosphorus source compounds and fluorine source compounds to perform ball milling; adding sodium source compounds and a granulating agent to perform ball milling to obtain a mixed slurry; and performing sand milling, spray drying and calcination on the mixed slurry to obtain the positive electrode composite oxide material. The chemical general formula of the positive electrode composite oxide material is: Na x M1 y M2 z O 2‑3 / 2α‑1 / 2β (PO4) α F β , M1 is an electrochemically active metal element ion, M2 is an electrochemically inactive metal element ion, and x, y, z, alpha and beta are the mole percentages of Na, M1, M2, (PO4) and F respectively.

Description

Technical Field

[0001] This invention belongs to the technical field of sodium-ion secondary battery materials, specifically relating to a method for manufacturing a high-entropy sodium-ion battery cathode material co-doped with anions and cations. Background Technology

[0002] Lithium-ion batteries, as electrochemical energy storage devices, are widely used in smart grid energy storage, portable electronic products, and new energy electric vehicles due to their advantages such as high operating voltage, long lifespan, no self-discharge, no memory effect, and environmental friendliness. However, due to the increasing demand for lithium-ion batteries and the continuous depletion of resources such as lithium and cobalt, the manufacturing cost and price of lithium-ion batteries are rising steadily, urgently requiring the development of new energy storage systems to replace lithium-ion batteries. Sodium-ion batteries, with their similar electrochemical working principle, comparable energy density and lifespan to lithium-ion batteries, and the greater abundance and lower cost of sodium resources compared to lithium, are considered a promising alternative energy storage system.

[0003] However, limited by the research, development, and application of cathode and anode materials for sodium-ion batteries, the energy density of current sodium-ion full batteries is relatively low. There is a need to develop cathode and anode materials with higher specific capacity to meet the energy density requirements of sodium-ion batteries. Currently developed cathode materials for sodium-ion batteries mainly include Prussian blue-based materials (such as NaM(II)M(III)(CN)6∙xH2O, where M is a metal element such as Fe, Mn, or Ni) and metal oxide materials (such as NaM...). x Cathode materials include O2 (where M is a metal element) and phosphates (such as NaFePO4, Na3V2(PO4)3, etc.). Prussian blue cathode materials are simple to prepare, but because they are mainly prepared through solution co-precipitation reactions, their crystal structures often contain irremovable water of crystallization, leading to poor cycle stability. Metal oxide cathode materials mainly focus on single-element metal cathodes, lacking a stable structure with non-electrochemically active metal elements; therefore, the resulting cathode materials have poor overall electrochemical performance. Phosphate cathode materials often achieve good cycle stability due to their stable crystal structure, but their operating voltage is relatively low, or they contain toxic elements and are expensive, thus hindering the development of low-cost, high-energy-density sodium-ion batteries.

[0004] Currently, there is an urgent need to develop new sodium-ion battery cathode materials with excellent comprehensive performance to meet the requirements of low cost, high energy density, and long cycle life in sodium-ion battery construction, thereby alleviating energy and environmental pressures.

[0005] In recent years, high-entropy oxides, as a novel type of compound, have attracted widespread attention from the scientific community due to their unique properties. Summary of the Invention

[0006] The purpose of this invention is to provide a method for manufacturing a high-entropy sodium-ion battery cathode material with co-doped anions and cations, characterized by stable crystal structure, good material cycle performance, uniform mixing of trace doped modified materials, good dispersion of trace materials, high maximum discharge capacity after battery fabrication, and high capacity retention.

[0007] Typically, high-entropy oxides contain five or more elements sharing the same atomic sites, forming stable solid solutions. Due to their complex composition, these materials often exhibit excellent properties, such as high fracture toughness, high strength, good high / low temperature performance, and good energy storage properties. Because of their complex composition, high-entropy oxides are difficult to synthesize using co-precipitation methods and are mostly synthesized using high-temperature solid-phase methods. However, high-temperature solid-phase synthesis methods present challenges in achieving homogeneous mixing of various raw materials, especially those with small weight proportions.

[0008] The technical solution adopted by the present invention to achieve the above objectives is as follows:

[0009] A method for manufacturing a cathode composite oxide material includes: mixing an inorganic metal compound, then pulverizing it; mixing the pulverized particles with an organometallic compound and water and ball-milling them; then adding a phosphorus source compound and a fluorine source compound and ball-milling them; finally adding a sodium source compound and a granulating agent and ball-milling them to obtain a slurry; and then sand-milling, spray-drying, and calcining the slurry to obtain the cathode composite oxide material; the general chemical formula of the cathode composite oxide material is: Na x M1 y M2 z O 2-3 / 2α-1 / 2β (PO4) α F β M1 represents electrochemically active metal ions, M2 represents non-electrochemically active metal ions, and x, y, z, α, and β represent the molar percentages of Na, M1, M2, (PO4), and F, respectively.

[0010] Preferably, 0.9 < x < 1.0, 0.85 < y < 0.9, 0.1 < z < 0.15, 0.01 < α < 0.03, and 0.01 < β < 0.03.

[0011] Preferably, M1 includes Cu 2+ Ni 2+ Mn 2+ Fe 3+ Co 3+ Cr 3+ and V 5+ At least one of them.

[0012] Preferably, M2 includes Mg 2+ Zn2+ Al 3+ Sn 4+ Mn 4+ Ti 4+ Mo 4+ Sb 4+ and Nb 5+ At least one of them.

[0013] Preferably, the inorganic metal compound includes at least one of copper oxide, nickel oxide, ferrous oxide, manganese monoxide, vanadium pentoxide, titanium dioxide, cobalt oxide, nickel carbonate, ferrous carbonate, manganese carbonate, chromium trioxide, and niobium pentoxide.

[0014] Preferably, the pulverizing process includes roller pulverization and airflow pulverization.

[0015] Preferably, the organometallic compound includes at least one of zinc acetate, molybdenum(II) acetate dimer, magnesium acetate, zirconium acetate, tin acetate, and antimony triacetate.

[0016] Preferably, the granulating agent includes at least one of polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and diethyl phthalate.

[0017] Preferably, the phosphorus source compound includes sodium phosphate.

[0018] Preferably, the fluorine source compound includes sodium fluoride.

[0019] Preferably, the sodium source compound includes sodium carbonate or sodium hydroxide.

[0020] This invention discloses the cathode composite oxide material prepared by the above method. The chemical formula of the cathode composite oxide material is: Na x M1 y M2 z O 2-3 / 2α-1 / 2β (PO4) α F β M1 represents electrochemically active metal ions, M2 represents non-electrochemically active metal ions, and x, y, z, α, and β represent the molar percentages of Na, M1, M2, (PO4), and F, respectively.

[0021] Preferably, the cathode composite oxide material includes any one of the following:

[0022] Material 1: Na 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo 0.04 O1.98 (PO4) 0.01 F 0.01 ;

[0023] Material 2: Na 0.82 Mg 0.05 Ni 0.15 Fe 0.3 Co 0.1 Mn 0.35 Zr 0.05 O 1.96 (PO4) 0.02 F 0.02 ;

[0024] Material 3: Na 0.98 Zn 0.05 Ni 0.30 Fe 0.23 Mn 0.35 Ti 0.03 Sn 0.04 O 1.94 (PO4) 0.03 F 0.03 ;

[0025] Material 4: Na 0.86 Mg 0.05 Cu 0.20 Fe 0.25 Cr 0.20 Mn 0.25 Sb 0.05 O 1.96 (PO4) 0.02 F 0.02 ;

[0026] Material 5: Na 0.94 Mg 0.06 Cu 0.15 Cr 0.13 Ni 0.25 Mn 0.35 Nb 0.06 O 1.98 (PO4) 0.01 F 0.01 .

[0027] This invention discloses a battery comprising the above-mentioned positive electrode composite oxide material.

[0028] This invention provides an improved high-temperature solid-state manufacturing method for spherical anion-cation co-doped high-entropy sodium-ion battery cathode composite oxide materials. The improved high-temperature solid-state synthesis process utilizes commonly used equipment in the materials industry. This invention creatively introduces a spray drying granulation process, primarily to improve the sphericity of the synthesized material, meeting the requirements of battery manufacturing, increasing the compaction density of the cathode material, and improving some electrochemical properties of the battery. This invention also provides a method for improving material performance through anion doping. Phosphate and fluoride ions replace a small amount of oxygen ions, stabilizing the crystal structure of the material and improving its cycle performance. Cycle performance is also a crucial technical indicator for batteries and a limiting factor in the commercialization and practical application of sodium-ion batteries. Furthermore, the amount of doped material is relatively small. If a pure solid-state synthesis method is used, the problem of uniform mixing of these trace doped materials cannot be well solved, inevitably affecting the doping modification effect. Therefore, this invention effectively solves this problem by introducing soluble substances to improve the dispersion of these trace doped materials. Therefore, the method of this invention has high practical operability.

[0029] This invention discloses an improved high-temperature solid-state manufacturing method for spherical high-entropy sodium-ion battery cathode composite oxide materials co-doped with anions and cations. The method is an improved solid-state method, comprising: firstly, primary crushing and air-jet milling of water-insoluble raw materials into 5-20 μm particles, then adding other water-soluble raw materials and performing wet ball milling, followed by sand milling, resulting in a slurry particle size of 100-300 nm, spray drying and granulation of the sand-milled slurry, controlling the spherical particle size to 7-12 μm, then calcining the sprayed particles in air or oxygen, and finally air-jet milling the calcined material to obtain the spherical high-entropy sodium-ion battery cathode composite oxide material co-doped with anions and cations.

[0030] In the manufacturing method of this invention, a two-step wet ball milling and sand milling process is adopted. The advantages are: firstly, it can ultrafinely crush some insoluble raw materials, improving the uniformity of raw material mixing; secondly, some trace amounts of soluble modified substances can be directly dissolved into the slurry, improving the dispersion effect of some water-soluble trace modified substances, and thus improving the electrochemical performance of the synthesized material.

[0031] In the manufacturing method of the present invention, the insoluble raw materials are preferably oxides or carbonates.

[0032] In the manufacturing method of the present invention, the preferred sodium source raw material is water-soluble Na2CO3 or NaOH.

[0033] In the manufacturing method of the present invention, the anionic dopant is preferably a water-soluble substance, such as Na3PO4 as the phosphorus source raw material; or NaF as the fluorine source raw material.

[0034] In the manufacturing method of the present invention, it is preferable to introduce other soluble acetate substances to introduce the doped cation, such as cobalt source material can be introduced by cobalt acetate, zirconium source material can be introduced by zirconium acetate, etc.

[0035] In the manufacturing method of the present invention, the soluble raw material is added last, and the order is as follows: other soluble raw materials, anionic dopant added after ball milling for half an hour, sodium source raw material added after ball milling for half an hour, ball milling for another half hour, sand milling, and spray drying and granulation after sand milling.

[0036] In the manufacturing method of the present invention, ball milling and sand milling equipment are preferred as raw material mixing and grinding equipment, and the particle size of the slurry after sand milling is 100-300nm; in order to improve the production capacity of the sand mill, it is preferred to first use air jet milling equipment to air jet mill the undissolved large particles of raw materials, and the particle size after milling is 5-20μm.

[0037] In the manufacturing method of this invention, spray drying equipment is preferred for drying and granulating the slurry. Polyvinyl alcohol granulating agent is added to the spray slurry to improve the sphericity of the spray-dried particles. This meets the material requirements for battery manufacturing, increases the compaction density of the cathode material, and improves some electrochemical properties of the battery.

[0038] In the manufacturing method of the present invention, the powder after spray drying needs to be calcined at a high temperature of 700℃-1000℃ for 24-48 hours.

[0039] In the preparation of a sodium-ion battery cathode composite oxide according to the present invention, copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, and titanium dioxide are mixed for 1-5 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles are controlled to be 5-20 μm. Then, deionized water, zinc acetate, and molybdenum(II) acetate dimer are added and ball-milled for 10-60 minutes. Then, sodium phosphate and sodium fluoride are added and ball-milled for 10-60 minutes. Finally, sodium carbonate and polyethylene are added. Alcohol is ball-milled for 10-60 min to obtain a mixed slurry. This slurry is then wet-milled to obtain a sand-milled slurry with particle size controlled at 100-300 nm. The slurry is then spray-dried to granulate, with particle size controlled at 7-12 μm. The dried granules are then calcined at 700-1000℃ for 24-48 h. Finally, the calcined material is subjected to air jet milling to obtain a spherical sodium-ion battery cathode composite oxide material, namely Na... 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo0.04 O 1.98 (PO4) 0.01 F 0.01 .

[0040] Preferably, in the preparation of the sodium-ion battery cathode composite oxide, the amount of copper oxide used is 40-60 wt% of manganese monoxide, the amount of nickel oxide used is 40-100 wt% of manganese monoxide, the amount of ferrous oxide used is 60-110 wt% of manganese monoxide, the amount of vanadium pentoxide used is 40-60 wt% of manganese monoxide, the amount of titanium dioxide used is 10-20 wt% of manganese monoxide, the amount of deionized water used is 200-450 wt% of manganese monoxide, the amount of zinc acetate used is 10-60 wt% of manganese monoxide, the amount of molybdenum(II) acetate dimer used is 20-50 wt% of manganese monoxide, the amount of sodium phosphate used is 2-20 wt% of manganese monoxide, the amount of sodium fluoride used is 1-5 wt% of manganese monoxide, the amount of sodium carbonate used is 80-250 wt% of manganese monoxide, and the amount of polyvinyl alcohol used is 1-20 wt% of manganese monoxide.

[0041] Preferably, in the preparation of the sodium-ion battery cathode composite oxide, methyl allyl alcohol polyoxyethylene ether (MEE) and diethyl phthalate (DET) can be added to the granulating agent. The amount of MEE used is 0.5-3 wt% of manganese monoxide, and the amount of DET is 0.4-2 wt% of manganese monoxide. This invention achieves anion doping by mixing MEE, DET, and polyvinyl alcohol in a slurry before spray drying granulation. The mixture is then ball-milled and sand-milled. Under the combined action of MEE, DET, and polyvinyl alcohol, anion doping is achieved through spray drying granulation and calcination. This improves the dispersion uniformity of trace dopants, enhances the structural stability and cycle performance of the material, and increases the maximum discharge capacity and capacity retention rate of the battery after it is manufactured.

[0042] In the preparation of a sodium-ion battery cathode composite oxide according to the present invention, nickel oxide, ferrous oxide, cobalt oxide, and manganese monoxide are mixed for 1-5 hours, then subjected to initial crushing by roller pressing and air jet milling. The pulverized particles are controlled to be 5-20 μm. Then, deionized water, magnesium acetate, and zirconium acetate are added and ball milled for 10-60 minutes. Then, sodium phosphate and sodium fluoride are added and ball milled for 10-60 minutes. Subsequently, sodium hydroxide and polyvinyl alcohol are added and ball milled for 10-60 minutes to obtain a mixed slurry. The mixed slurry is then wet-milled to obtain a sand-milled slurry. The particle size of the sand-milled slurry is controlled to be 100-300 nm. Then, it is spray-dried and granulated. The particle size of the dried granulated particles is controlled to be 7-12 μm. Then, the dried granulated particles are calcined at 700-1000℃ for 24-48 hours. Finally, the calcined material is air-milled to obtain a spherical sodium-ion battery cathode composite oxide material, i.e., Na 0.82 Mg 0.05 Ni 0.15 Fe 0.3 Co 0.1 Mn 0.35 Zr 0.05 O 1.96 (PO4) 0.02 F 0.02 .

[0043] Preferably, in the preparation of the sodium-ion battery cathode composite oxide, the amount of nickel oxide used is 40-100 wt% of manganese monoxide, the amount of ferrous oxide used is 60-110 wt% of manganese monoxide, the amount of cobalt oxide used is 20-40 wt% of manganese monoxide, the amount of deionized water used is 200-450 wt% of manganese monoxide, the amount of magnesium acetate used is 10-60 wt% of manganese monoxide, the amount of zirconium acetate used is 20-50 wt% of manganese monoxide, the amount of sodium phosphate used is 2-20 wt% of manganese monoxide, the amount of sodium fluoride used is 1-5 wt% of manganese monoxide, the amount of sodium hydroxide used is 80-250 wt% of manganese monoxide, and the amount of polyvinyl alcohol used is 1-20 wt% of manganese monoxide.

[0044] In the preparation of a sodium-ion battery cathode composite oxide according to the present invention, nickel carbonate, ferrous carbonate, manganese carbonate, and titanium dioxide are mixed for 1-5 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles are controlled to be 5-20 μm. Then, deionized water, zinc acetate, and tin acetate are added and ball milled for 10-60 minutes. Next, sodium phosphate and sodium fluoride are added and ball milled for 10-60 minutes. Subsequently, sodium carbonate and polyvinyl alcohol are added and ball milled for 10-60 minutes to obtain a mixed slurry. The mixed slurry is then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. Then, spray drying is performed to granulate the granulated particles, with the particle size controlled to be 7-12 μm. The granulated particles are then calcined at 700-1000℃ for 24-48 hours. Finally, the calcined material is air-milled to obtain a spherical sodium-ion battery cathode composite oxide material, i.e., Na 0.98 Zn 0.05 Ni 0.30 Fe 0.23 Mn 0.35 Ti 0.03 Sn 0.04 O 1.94 (PO4) 0.03 F 0.03 .

[0045] Preferably, in the preparation of the sodium-ion battery cathode composite oxide, the amount of nickel carbonate used is 40-100 wt% of manganese carbonate, the amount of ferrous carbonate used is 60-110 wt% of manganese carbonate, the amount of titanium dioxide used is 1-10 wt% of manganese carbonate, the amount of deionized water used is 200-450 wt% of manganese carbonate, the amount of zinc acetate used is 10-60 wt% of manganese carbonate, the amount of tin acetate used is 10-30 wt% of manganese carbonate, the amount of sodium phosphate used is 2-20 wt% of manganese carbonate, the amount of sodium fluoride used is 1-5 wt% of manganese carbonate, the amount of sodium carbonate used is 80-250 wt% of manganese carbonate, and the amount of polyvinyl alcohol used is 1-20 wt% of manganese carbonate.

[0046] In the preparation of a sodium-ion battery cathode composite oxide according to the present invention, copper oxide, ferrous carbonate, chromium trioxide, and manganese carbonate are mixed for 1-5 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles are controlled to be 5-20 μm. Then, deionized water, magnesium acetate, and antimony triacetate are added and ball milled for 10-60 minutes. Next, sodium phosphate and sodium fluoride are added and ball milled for 10-60 minutes. Subsequently, sodium carbonate and polyvinyl alcohol are added and ball milled for 10-60 minutes to obtain a mixed slurry. The mixed slurry is then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. Then, spray drying is performed to granulate the granulated particles, with the particle size controlled to be 7-12 μm. The granulated particles are then calcined at 700-1000℃ for 24-48 hours. Finally, the calcined material is air-milled to obtain a spherical sodium-ion battery cathode composite oxide material, i.e., Na 0.86 Mg 0.05 Cu 0.20 Fe 0.25 Cr 0.20 Mn 0.25 Sb 0.05 O 1.96 (PO4) 0.02 F 0.02 .

[0047] Preferably, in the preparation of the sodium-ion battery cathode composite oxide, the amount of copper oxide used is 40-60 wt% of manganese carbonate, the amount of ferrous carbonate used is 90-110 wt% of manganese carbonate, the amount of chromium trioxide used is 100-110 wt% of manganese carbonate, the amount of deionized water used is 200-450 wt% of manganese carbonate, the amount of magnesium acetate used is 10-60 wt% of manganese carbonate, the amount of antimony triacetate used is 30-50 wt% of manganese carbonate, the amount of sodium phosphate used is 2-20 wt% of manganese carbonate, the amount of sodium fluoride used is 1-5 wt% of manganese carbonate, the amount of sodium carbonate used is 80-250 wt% of manganese carbonate, and the amount of polyvinyl alcohol used is 1-20 wt% of manganese carbonate.

[0048] In the preparation of a sodium-ion battery cathode composite oxide according to the present invention, copper oxide, chromium trioxide, nickel carbonate, manganese carbonate, and niobium pentoxide are mixed for 1-5 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles are controlled to be 5-20 μm. Then, deionized water and magnesium acetate are added and ball milling is performed for 10-60 minutes. Then, sodium phosphate and sodium fluoride are added and ball milling is performed for 10-60 minutes. Subsequently, sodium hydroxide and polyvinyl alcohol are added and ball milling is performed for 10-60 minutes to obtain a mixed slurry. The mixed slurry is then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. Then, spray drying and granulation are performed, with the particle size of the dried granules controlled to be 7-12 μm. Then, the dried granules are calcined at 700-1000℃ for 24-48 hours. Finally, the calcined material is air-milled to obtain a spherical sodium-ion battery cathode composite oxide material, i.e., Na 0.94 Mg 0.06 Cu 0.15 Cr 0.13 Ni 0.25 Mn 0.35 Nb 0.06 O 1.98 (PO4) 0.01 F 0.01 .

[0049] Preferably, in the preparation of the sodium-ion battery cathode composite oxide, the amount of copper oxide used is 20-60 wt% of manganese carbonate, the amount of chromium trioxide used is 40-60 wt% of manganese carbonate, the amount of nickel carbonate used is 40-100 wt% of manganese carbonate, the amount of niobium pentoxide used is 10-30 wt% of manganese carbonate, the amount of deionized water used is 200-450 wt% of manganese carbonate, the amount of magnesium acetate used is 10-60 wt% of manganese carbonate, the amount of sodium phosphate used is 2-20 wt% of manganese carbonate, the amount of sodium fluoride used is 1-5 wt% of manganese carbonate, the amount of sodium hydroxide used is 80-250 wt% of manganese carbonate, and the amount of polyvinyl alcohol used is 1-20 wt% of manganese carbonate.

[0050] Preferably, in the preparation of the sodium-ion battery cathode composite oxide, ethylene glycol dibutyrate can also be added to the granulating agent, and the amount of ethylene glycol dibutyrate used is 0.1-2 wt% of manganese monoxide. In addition to using methyl allyl alcohol polyoxyethylene ether, diethyl phthalate, and polyvinyl alcohol, this invention can also add ethylene glycol dibutyrate. Under the combined action of the above reagents, a cathode composite oxide material is prepared, which further improves the maximum discharge capacity and capacity retention rate of the battery after it is made into a battery.

[0051] This invention involves mixing inorganic metal compounds, followed by pulverization. The pulverized particles are then mixed with an organometallic compound and water and ball-milled. A phosphorus source compound and a fluorine source compound are then added and ball-milled again. Finally, a sodium source compound and a granulating agent are added and ball-milled to obtain a slurry. This slurry is then sand-milled, spray-dried, and calcined to obtain a cathode composite oxide material. The chemical formula of the cathode composite oxide material is: Na. x M1 y M2 z O 2-3 / 2α-1 / 2β (PO4) α F β M1 represents electrochemically active metal ions, M2 represents non-electrochemically active metal ions, and x, y, z, α, and β represent the molar percentages of Na, M1, M2, (PO4), and F, respectively, with 0.9 < x < 1.0, 0.85 < y < 0.9, 0.1 < z < 0.15, 0.01 < α < 0.03, and 0.01 < β < 0.03. Therefore, it has the following beneficial effects: the positive electrode composite oxide material has a stable crystal structure, good material cycle performance, uniform mixing of trace doped modified materials, and good dispersion of trace materials. After a battery is made from the positive electrode composite oxide material, the battery has a high maximum discharge capacity and high capacity retention rate. Therefore, this invention is a method for manufacturing a high-entropy sodium-ion battery positive electrode material with co-doped anions and cations, exhibiting a stable crystal structure, good material cycle performance, uniform mixing of trace doped modified materials, good dispersion of trace materials, high maximum discharge capacity after battery fabrication, and high capacity retention rate. Attached Figure Description

[0052] Figure 1 This is a SEM image of the positive electrode composite oxide material.

[0053] Figure 2 This is a diagram showing the maximum discharge capacity.

[0054] Figure 3 This is a capacity retention graph. Detailed Implementation

[0055] 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 some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0056] The concepts involved in this application will first be described with reference to the accompanying drawings. It should be noted that the following descriptions of various concepts are only for the purpose of making the content of this application easier to understand and do not constitute a limitation on the scope of protection of this application; furthermore, the embodiments and features in the embodiments of this application can be combined with each other unless otherwise specified. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0057] Example 1: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0058] Preparation of sodium-ion battery cathode composite oxide: Copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, and titanium dioxide were mixed for 2 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles were controlled to be 5-20 μm. Then, deionized water, zinc acetate, and molybdenum(II) acetate dimer were added and ball-milled for 30 minutes. Sodium phosphate and sodium fluoride were then added and ball-milled for 30 minutes. Subsequently, sodium carbonate and polyvinyl alcohol were added and ball-milled for 30 minutes to obtain a mixed slurry. The mixed slurry was then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. Then, spray-drying was performed to granulate the granulated particles, with the particle size controlled to be 7-12 μm. The granulated particles were then calcined at 850℃ for 34 hours. Finally, the calcined material was air-milled to obtain spherical sodium-ion battery cathode composite oxide material, i.e., Na 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo 0.04 O 1.98 (PO4) 0.01 F 0.01 The amounts of copper oxide used were 44.96 wt% of manganese monoxide, nickel oxide 45.64 wt% of manganese monoxide, ferrous oxide 67.52 wt% of manganese monoxide, vanadium pentoxide 51.31 wt% of manganese monoxide, titanium dioxide 15.01 wt% of manganese monoxide, deionized water 407.77 wt% of manganese monoxide, zinc acetate 43.11 wt% of manganese monoxide, molybdenum(II) acetate dimer 40.23 wt% of manganese monoxide, sodium phosphate 7.71 wt% of manganese monoxide, sodium fluoride 1.97 wt% of manganese monoxide, sodium carbonate 220.58 wt% of manganese monoxide, and polyvinyl alcohol 10.48 wt% of manganese monoxide.

[0059] Example 2: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0060] Preparation of sodium-ion battery cathode composite oxide: Nickel oxide, ferrous oxide, cobalt oxide, and manganese monoxide were mixed for 3 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles were controlled to be 5-20 μm. Then, deionized water, magnesium acetate, and zirconium acetate were added and ball milled for 30 minutes. Next, sodium phosphate and sodium fluoride were added and ball milled for 30 minutes. Finally, sodium hydroxide and polyvinyl alcohol were added and ball milled for 30 minutes to obtain a slurry. The slurry was then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. The slurry was then spray-dried to granulate, with the dried granulated particles controlled to be 7-12 μm. The dried granulated particles were then calcined at 750℃ for 28 hours. Finally, the calcined material was air-milled to obtain spherical sodium-ion battery cathode composite oxide material, i.e., Na... 0.82 Mg 0.05 Ni 0.15 Fe 0.3 Co 0.1 Mn 0.35 Zr 0.05 O 1.96 (PO4) 0.02 F 0.02 The amounts of nickel oxide used are 45.13 wt% of manganese monoxide, ferrous oxide is 86.81 wt% of manganese monoxide, cobalt oxide is 30.18 wt% of manganese monoxide, deionized water is 321.30 wt% of manganese monoxide, magnesium acetate is 28.72 wt% of manganese monoxide, zirconium acetate is 30.46 wt% of manganese monoxide, sodium phosphate is 13.21 wt% of manganese monoxide, sodium fluoride is 3.38 wt% of manganese monoxide, sodium hydroxide is 122.78 wt% of manganese monoxide, and polyvinyl alcohol is 8.14 wt% of manganese monoxide.

[0061] Example 3: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0062] Preparation of sodium-ion battery cathode composite oxide: Nickel carbonate, ferrous carbonate, manganese carbonate, and titanium dioxide were mixed for 3 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles were controlled to be 5-20 μm. Then, deionized water, zinc acetate, and tin acetate were added and ball milled for 30 minutes. Next, sodium phosphate and sodium fluoride were added and ball milled for 30 minutes. Then, sodium carbonate and polyvinyl alcohol were added and ball milled for 30 minutes to obtain a slurry. The slurry was then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. The slurry was then spray-dried to granulate, with the particle size controlled to be 7-12 μm. The granulated particles were then calcined at 900℃ for 30 hours. Finally, the calcined material was air-milled to obtain spherical sodium-ion battery cathode composite oxide material, i.e., Na... 0.98 Zn 0.05 Ni 0.30 Fe 0.23 Mn 0.35 Ti 0.03 Sn 0.04 O 1.94 (PO4) 0.03 F 0.03 The amounts of nickel carbonate used are 88.52 wt% of manganese carbonate, ferrous carbonate used are 66.23 wt% of manganese carbonate, titanium dioxide used are 5.95 wt% of manganese carbonate, deionized water used are 307.00 wt% of manganese carbonate, zinc acetate used are 22.75 wt% of manganese carbonate, tin acetate used are 23.54 wt% of manganese carbonate, sodium phosphate used are 12.22 wt% of manganese carbonate, sodium fluoride used are 3.13 wt% of manganese carbonate, sodium carbonate used are 116.68 wt% of manganese carbonate, and polyvinyl alcohol used are 5.77 wt% of manganese carbonate.

[0063] Example 4: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0064] Preparation of sodium-ion battery cathode composite oxide: Copper oxide, ferrous carbonate, chromium trioxide, and manganese carbonate were mixed for 3 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles were controlled to be 5-20 μm. Then, deionized water, magnesium acetate, and antimony triacetate were added and ball milled for 30 minutes. Next, sodium phosphate and sodium fluoride were added and ball milled for 30 minutes. Then, sodium carbonate and polyvinyl alcohol were added and ball milled for 30 minutes to obtain a mixed slurry. The mixed slurry was then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. This slurry was then spray-dried to granulate, with the dried granulated particles controlled to be 7-12 μm. The dried granulated particles were then calcined at 880℃ for 26 hours. Finally, the calcined material was air-milled to obtain spherical sodium-ion battery cathode composite oxide material, i.e., Na... 0.86 Mg 0.05 Cu 0.20 Fe 0.25 Cr 0.20 Mn 0.25 Sb 0.05 O 1.96 (PO4) 0.02 F 0.02 The amounts of copper oxide used are 55.36 wt% of manganese carbonate, ferrous carbonate is 100.79 wt% of manganese carbonate, chromium trioxide is 105.78 wt% of manganese carbonate, deionized water is 427.94 wt% of manganese carbonate, magnesium acetate is 24.81 wt% of manganese carbonate, antimony triacetate is 41.2 wt% of manganese carbonate, sodium phosphate is 11.41 wt% of manganese carbonate, sodium fluoride is 2.92 wt% of manganese carbonate, sodium carbonate is 170.95 wt% of manganese carbonate, and polyvinyl alcohol is 7.34 wt% of manganese carbonate.

[0065] Example 5: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0066] Preparation of sodium-ion battery cathode composite oxide: Copper oxide, chromium trioxide, nickel carbonate, manganese carbonate, and niobium pentoxide were mixed for 3 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles were controlled to be 5-20 μm. Then, deionized water and magnesium acetate were added and ball milled for 30 minutes. Sodium phosphate and sodium fluoride were then added and ball milled for 30 minutes. Subsequently, sodium hydroxide and polyvinyl alcohol were added and ball milled for 30 minutes to obtain a mixed slurry. The mixed slurry was then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. Then, spray drying was performed to granulate the granulated particles, with a particle size controlled to be 7-12 μm. The granulated particles were then calcined at 730℃ for 32 hours. Finally, the calcined material was air-milled to obtain spherical sodium-ion battery cathode composite oxide material, i.e., Na 0.94 Mg 0.06 Cu 0.15 Cr 0.13 Ni 0.25 Mn 0.35 Nb 0.06 O 1.98 (PO4) 0.01 F 0.01 The amounts of copper oxide, chromium trioxide, nickel carbonate, niobium pentoxide, and deionized water used were 29.66 wt% of manganese carbonate, 49.11 wt% of manganese carbonate, 73.76 wt% of manganese carbonate, 19.82 wt% of manganese carbonate, 293.62 wt% of manganese carbonate, 21.27 wt% of manganese carbonate, 4.07 wt% of manganese carbonate, 1.04 wt% of manganese carbonate, 92.16 wt% of manganese carbonate, and 5.55 wt% of manganese carbonate, respectively.

[0067] Example 6: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0068] Preparation of composite oxide for sodium-ion battery cathode: Copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, and titanium dioxide were mixed for 2 hours, followed by initial crushing by roller pressing and air jet milling. The particle size after milling was controlled at 5-20 μm. Then, deionized water, zinc acetate, and molybdenum(II) acetate dimer were added and ball-milled for 30 minutes. Sodium phosphate and sodium fluoride were then added and ball-milled for 30 minutes. Finally, sodium carbonate, polyvinyl alcohol, and methyl allyl alcohol polyoxyethylene ether were added. Diethyl phthalate was ball-milled for 30 minutes to obtain a mixed slurry. This slurry was then wet-milled to obtain a sand-milled slurry with particle size controlled at 100-300 nm. The slurry was then spray-dried to granulate, with particle size controlled at 7-12 μm. The dried granules were then calcined at 850℃ for 34 hours. Finally, the calcined material was subjected to air jet milling to obtain a spherical sodium-ion battery cathode composite oxide material, namely Na... 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo 0.04 O 1.98 (PO4) 0.01 F 0.01 . The amount of copper oxide used is 44.96 wt% of manganese monoxide, the amount of nickel oxide used is 45.64 wt% of manganese monoxide, the amount of ferrous oxide used is 67.52 wt% of manganese monoxide, the amount of vanadium pentoxide used is 51.31 wt% of manganese monoxide, the amount of titanium dioxide used is 15.01 wt% of manganese monoxide, the amount of deionized water used is 407.77 wt% of manganese monoxide, the amount of zinc acetate used is 43.11 wt% of manganese monoxide, the amount of molybdenum(II) acetate dimer used is 40.23 wt% of manganese monoxide, the amount of sodium phosphate used is 7.71 wt% of manganese monoxide, the amount of sodium fluoride used is 1.97 wt% of manganese monoxide, the amount of sodium carbonate used is 220.58 wt% of manganese monoxide, the amount of polyvinyl alcohol used is 10.48 wt% of manganese monoxide, the amount of methyl allyl alcohol polyoxyethylene ether used is 2.5 wt% of manganese monoxide, and the amount of diethyl phthalate used is 1.8 wt% of manganese monoxide.

[0069] Example 7: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0070] Preparation of composite oxide for sodium-ion battery cathode: Copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, and titanium dioxide were mixed for 2 hours, followed by initial crushing by roller pressing and air jet milling. The particle size after milling was controlled at 5-20 μm. Then, deionized water, zinc acetate, and molybdenum(II) acetate dimer were added and ball-milled for 30 minutes. Sodium phosphate and sodium fluoride were then added and ball-milled for 30 minutes. Finally, sodium carbonate, polyvinyl alcohol, and methyl allyl alcohol polyoxyethylene ether were added. Diethyl phthalate was ball-milled for 30 minutes to obtain a mixed slurry. This slurry was then wet-milled to obtain a sand-milled slurry with particle size controlled at 100-300 nm. The slurry was then spray-dried to granulate, with particle size controlled at 7-12 μm. The dried granules were then calcined at 850℃ for 34 hours. Finally, the calcined material was subjected to air jet milling to obtain a spherical sodium-ion battery cathode composite oxide material, namely Na... 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo 0.04 O 1.98 (PO4) 0.01 F 0.01 The amounts used are as follows: copper oxide (44.96 wt%), nickel oxide (45.64 wt%), ferrous oxide (67.52 wt%), vanadium pentoxide (51.31 wt%), titanium dioxide (15.01 wt%), deionized water (407.77 wt%), zinc acetate (43.11 wt%), molybdenum(II) acetate dimer (40.23 wt%), sodium phosphate (7.71 wt%), sodium fluoride (1.97 wt%), sodium carbonate (220.58 wt%), polyvinyl alcohol (10.48 wt%), methyl allyl alcohol polyoxyethylene ether (1 wt%), and diethyl phthalate (1 wt%).

[0071] Example 8: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0072] Preparation of sodium-ion battery cathode composite oxide: Copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, and titanium dioxide were mixed for 2 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles were controlled to be 5-20 μm. Then, deionized water, zinc acetate, and molybdenum(II) acetate dimer were added and ball-milled for 30 minutes. Sodium phosphate and sodium fluoride were then added and ball-milled for another 30 minutes. Finally, sodium carbonate, polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and phthalic acid were added. Diethyl formate and ethylene glycol dibutyrate were ball-milled for 30 minutes to obtain a mixed slurry. This slurry was then wet-milled to obtain a sand-milled slurry with particle size controlled at 100-300 nm. The slurry was then spray-dried to granulate, with particle size controlled at 7-12 μm. The dried granules were then calcined at 850℃ for 34 hours. Finally, the calcined material was subjected to air jet milling to obtain a spherical sodium-ion battery cathode composite oxide material, namely Na... 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo 0.04 O 1.98 (PO4) 0.01 F 0.01 The amounts used were: copper oxide (44.96 wt% of manganese oxide), nickel oxide (45.64 wt% of manganese oxide), ferrous oxide (67.52 wt% of manganese oxide), vanadium pentoxide (51.31 wt% of manganese oxide), titanium dioxide (15.01 wt% of manganese oxide), deionized water (407.77 wt% of manganese oxide), zinc acetate (43.11 wt% of manganese oxide), and molybdenum(II) acetate dimer (…). The amount of manganese monoxide used is 40.23 wt%, sodium phosphate is 7.71 wt%, sodium fluoride is 1.97 wt%, sodium carbonate is 220.58 wt%, polyvinyl alcohol is 10.48 wt%, methyl allyl alcohol polyoxyethylene ether is 3 wt%, diethyl phthalate is 2 wt%, and ethylene glycol dibutyrate is 1.6 wt%.

[0073] Example 9: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0074] Preparation of sodium-ion battery cathode composite oxide: Copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, and titanium dioxide were mixed for 2 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles were controlled to be 5-20 μm. Then, deionized water, zinc acetate, and molybdenum(II) acetate dimer were added and ball-milled for 30 minutes. Sodium phosphate and sodium fluoride were then added and ball-milled for another 30 minutes. Finally, sodium carbonate, polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and phthalic acid were added. Diethyl formate and ethylene glycol dibutyrate were ball-milled for 30 minutes to obtain a mixed slurry. This slurry was then wet-milled to obtain a sand-milled slurry with particle size controlled at 100-300 nm. The slurry was then spray-dried to granulate, with particle size controlled at 7-12 μm. The dried granules were then calcined at 850℃ for 34 hours. Finally, the calcined material was subjected to air jet milling to obtain a spherical sodium-ion battery cathode composite oxide material, namely Na... 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo 0.04 O 1.98 (PO4) 0.01 F 0.01 The amounts used were: copper oxide (44.96 wt% of manganese oxide), nickel oxide (45.64 wt% of manganese oxide), ferrous oxide (67.52 wt% of manganese oxide), vanadium pentoxide (51.31 wt% of manganese oxide), titanium dioxide (15.01 wt% of manganese oxide), deionized water (407.77 wt% of manganese oxide), zinc acetate (43.11 wt% of manganese oxide), and molybdenum(II) acetate dimer (…). The amount of manganese monoxide used is 40.23 wt%, sodium phosphate is 7.71 wt%, sodium fluoride is 1.97 wt%, sodium carbonate is 220.58 wt%, polyvinyl alcohol is 10.48 wt%, methyl allyl alcohol polyoxyethylene ether is 3 wt%, diethyl phthalate is 2 wt%, and ethylene glycol dibutyrate is 0.5 wt%.

[0075] Comparative Example 1: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0076] Preparation of sodium-ion battery cathode composite oxide: Copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, and titanium dioxide were mixed for 2 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles were controlled to be 5-20 μm. Then, deionized water, zinc acetate, and molybdenum(II) acetate dimer were added and ball-milled for 30 minutes. Sodium phosphate and sodium fluoride were then added and ball-milled for 30 minutes. Subsequently, sodium carbonate, polyvinyl alcohol, and methyl allyl alcohol polyoxyethylene ether were added and ball-milled for 30 minutes to obtain a mixed slurry. The mixed slurry was then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. Then, spray-drying was performed to granulate the granulated particles, with the particle size controlled to be 7-12 μm. The granulated particles were then calcined at 850℃ for 34 hours. Finally, the calcined material was air-milled to obtain spherical sodium-ion battery cathode composite oxide material, i.e., Na 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo 0.04 O 1.98 (PO4) 0.01 F 0.01 The amounts used are as follows: copper oxide 44.96 wt% of manganese monoxide, nickel oxide 45.64 wt% of manganese monoxide, ferrous oxide 67.52 wt% of manganese monoxide, vanadium pentoxide 51.31 wt% of manganese monoxide, titanium dioxide 15.01 wt% of manganese monoxide, deionized water 407.77 wt% of manganese monoxide, zinc acetate 43.11 wt% of manganese monoxide, molybdenum(II) acetate dimer 40.23 wt% of manganese monoxide, sodium phosphate 7.71 wt% of manganese monoxide, sodium fluoride 1.97 wt% of manganese monoxide, sodium carbonate 220.58 wt% of manganese monoxide, polyvinyl alcohol 10.48 wt% of manganese monoxide, and methyl allyl alcohol polyoxyethylene ether 1 wt% of manganese monoxide.

[0077] Comparative Example 2: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0078] Preparation of sodium-ion battery cathode composite oxide: Copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, and titanium dioxide were mixed for 2 hours, followed by initial crushing by roller pressing and air jet milling. The pulverized particles were controlled to be 5-20 μm. Then, deionized water, zinc acetate, and molybdenum(II) acetate dimer were added and ball-milled for 30 minutes. Sodium phosphate and sodium fluoride were then added and ball-milled for 30 minutes. Subsequently, sodium carbonate, polyvinyl alcohol, and diethyl phthalate were added and ball-milled for 30 minutes to obtain a mixed slurry. The mixed slurry was then wet-milled to obtain a sand-milled slurry with a particle size controlled to be 100-300 nm. Then, spray-drying was performed to granulate the granulated particles, with the particle size controlled to be 7-12 μm. The granulated particles were then calcined at 850℃ for 34 hours. Finally, the calcined material was air-milled to obtain spherical sodium-ion battery cathode composite oxide material, i.e., Na 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo 0.0 4O 1.98 (PO4) 0.01 F 0.01 The amounts used were: copper oxide (44.96 wt% of manganese oxide), nickel oxide (45.64 wt% of manganese oxide), ferrous oxide (67.52 wt% of manganese oxide), vanadium pentoxide (51.31 wt% of manganese oxide), titanium dioxide (15.01 wt% of manganese oxide), deionized water (407.77 wt% of manganese oxide), zinc acetate (43.11 wt% of manganese oxide), molybdenum(II) acetate dimer (40.23 wt% of manganese oxide), sodium phosphate (7.71 wt% of manganese oxide), sodium fluoride (1.97 wt% of manganese oxide), sodium carbonate (220.58 wt% of manganese oxide), polyvinyl alcohol (10.48 wt% of manganese oxide), and diethyl phthalate (1 wt% of manganese oxide).

[0079] Comparative Example 3: A method for manufacturing a composite oxide cathode for sodium-ion batteries

[0080] Preparation of composite oxide for sodium-ion battery cathode: Copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, and titanium dioxide were mixed for 2 hours, followed by initial crushing by roller pressing and air jet milling. The particle size after milling was controlled at 5-20 μm. Then, deionized water, zinc acetate, and molybdenum(II) acetate dimer were added and ball-milled for 30 minutes. Sodium phosphate and sodium fluoride were then added and ball-milled for 30 minutes. Finally, sodium carbonate, polyvinyl alcohol, and methyl allyl alcohol polyoxyethylene ether were added. Diethyl phthalate was ball-milled for 30 minutes to obtain a mixed slurry. This slurry was then wet-milled to obtain a sand-milled slurry with particle size controlled at 100-300 nm. The slurry was then spray-dried to granulate, with particle size controlled at 7-12 μm. The dried granules were then calcined at 850℃ for 34 hours. Finally, the calcined material was subjected to air jet milling to obtain a spherical sodium-ion battery cathode composite oxide material, namely Na... 0.9 Zn 0.05 Cu 0.12 Ni 0.13 Fe 0.20 Mn 0.30 V 0.12 Ti 0.04 Mo 0.04 O 1.98 (PO4) 0.01 F 0.01 . The amounts of copper oxide used are 44.96 wt% of manganese monoxide, nickel oxide used are 45.64 wt% of manganese monoxide, ferrous oxide used are 67.52 wt% of manganese monoxide, vanadium pentoxide used are 51.31 wt% of manganese monoxide, titanium dioxide used are 15.01 wt% of manganese monoxide, deionized water used are 407.77 wt% of manganese monoxide, zinc acetate used are 43.11 wt% of manganese monoxide, molybdenum(II) acetate dimer used are 40.23 wt% of manganese monoxide, sodium phosphate used are 7.71 wt% of manganese monoxide, sodium fluoride used are 1.97 wt% of manganese monoxide, sodium carbonate used are 220.58 wt% of manganese monoxide, polyvinyl alcohol used are 10.48 wt% of manganese monoxide, methyl allyl alcohol polyoxyethylene ether used are 0.1 wt% of manganese monoxide, and diethyl phthalate used are 0.1 wt% of manganese monoxide.

[0081] Experimental example:

[0082] The surface morphology of the sodium-ion battery cathode composite oxide prepared in Example 1 was characterized in this invention, and the results are as follows: Figure 1 As shown, the sodium-ion battery cathode composite oxide is spherical in shape with a rough and uneven surface.

[0083] Preparation of sodium-ion batteries: Sodium-ion battery positive electrode composite oxide, sodium carboxymethyl cellulose, carbon black and water were mixed in a mass ratio of 8:1:1:24 to obtain a positive electrode slurry. The positive electrode slurry was coated on an aluminum sheet to serve as the positive electrode of the sodium-ion battery. A glass fiber film was used as the separator of the battery. A 1M NaClO4 solution was used as the electrolyte. The solvent in the electrolyte was ethylene carbonate and dimethyl carbonate, which were mixed in a volume ratio of 1:1. A sodium sheet was used as the negative electrode. The battery was assembled in a vacuum glove box.

[0084] In this invention, batteries made from the positive electrode composite oxide materials prepared in Examples 1, 6-9, and Comparative Examples 1-3 were subjected to charge-discharge tests. The charge-discharge range was 1.8V to 4V, and the current density was 0.1 A·g. -1 The maximum discharge capacity of the battery obtained is as follows: Figure 2As shown, S1 is Example 1, S6 is Example 6, S7 is Example 7, S8 is Example 8, S9 is Example 9, D1 is Comparative Example 1, D2 is Comparative Example 2, and D3 is Comparative Example 3. In this invention, inorganic metal compounds are mixed and then pulverized. The pulverized particles are mixed with an organometallic compound and water and ball-milled. Then, a phosphorus source compound and a fluorine source compound are added and ball-milled again. A sodium source compound and a granulating agent are then added and ball-milled to obtain a slurry. The slurry is then sand-milled, spray-dried, and calcined to obtain a positive electrode composite oxide. Materials: Inorganic metal compounds may be selected from at least one of copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, titanium dioxide, cobalt oxide, nickel carbonate, ferrous carbonate, manganese carbonate, chromium trioxide, and niobium pentoxide; organometallic compounds may be selected from at least one of zinc acetate, molybdenum(II) acetate dimer, magnesium acetate, zirconium acetate, tin acetate, and antimony triacetate; granulating agents may be selected from at least one of polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and diethyl phthalate; phosphorus source compounds include sodium phosphate; fluorine source compounds include fluorine. Sodium hydroxide; the sodium source compound includes sodium carbonate or sodium hydroxide; the positive electrode composite oxide prepared by this invention has a good maximum discharge capacity after being made into a battery. After preparing the positive electrode composite oxide material using polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and diethyl phthalate, the maximum discharge capacity of the battery obtained by this invention is better than that of a battery made using only polyvinyl alcohol positive electrode composite oxide material; furthermore, if only polyvinyl alcohol and methyl allyl alcohol polyoxyethylene ether are used to make the battery, the maximum discharge capacity of the battery cannot be significantly improved; if only polyvinyl alcohol and diethyl phthalate are used to make the battery, the maximum discharge capacity of the battery cannot be significantly improved; if polyvinyl alcohol is used but the amount of methyl allyl alcohol polyoxyethylene ether and diethyl phthalate is too low, the maximum discharge capacity of the battery cannot be significantly improved; furthermore, after using polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and diethyl phthalate, ethylene glycol dibutyrate can also be added to further improve the maximum discharge capacity of the battery.

[0085] In this invention, batteries made from the positive electrode composite oxide materials prepared in Examples 1, 6-9, and Comparative Examples 1-3 were subjected to charge-discharge tests. The charge-discharge range was 1.8V to 4V, and the current density was 0.1 A·g. -1 After 200 cycles, the battery capacity retention rate is as follows: Figure 3As shown, S1 is Example 1, S6 is Example 6, S7 is Example 7, S8 is Example 8, S9 is Example 9, D1 is Comparative Example 1, D2 is Comparative Example 2, and D3 is Comparative Example 3. In this invention, inorganic metal compounds are mixed and then pulverized. The pulverized particles are mixed with organometallic compounds and water and ball-milled. Then, phosphorus and fluorine source compounds are added and ball-milled again. Next, sodium source compounds and granulators are added and ball-milled to obtain a slurry. The slurry is then sand-milled, spray-dried, and calcined to obtain a positive electrode composite oxide. Materials: Inorganic metal compounds may be selected from at least one of copper oxide, nickel oxide, ferrous oxide, manganese oxide, vanadium pentoxide, titanium dioxide, cobalt oxide, nickel carbonate, ferrous carbonate, manganese carbonate, chromium trioxide, and niobium pentoxide; Organometallic compounds may be selected from at least one of zinc acetate, molybdenum(II) acetate dimer, magnesium acetate, zirconium acetate, tin acetate, and antimony triacetate; Granulating agents may be selected from at least one of polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and diethyl phthalate; Phosphorus source compounds include sodium phosphate; Fluorine source compounds... The invention includes sodium fluoride; the sodium source compound includes sodium carbonate or sodium hydroxide; the positive electrode composite oxide prepared by this invention has good capacity retention after being made into a battery. The capacity retention of the battery obtained by using polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and diethyl phthalate together to prepare the positive electrode composite oxide material is better than that of a battery made using only polyvinyl alcohol. Furthermore, if only polyvinyl alcohol and methyl allyl alcohol polyoxyethylene ether are used to make the battery, the capacity retention cannot be significantly improved; similarly, if only polyvinyl alcohol and diethyl phthalate are used, the capacity retention cannot be significantly improved; if polyvinyl alcohol is used but the amount of methyl allyl alcohol polyoxyethylene ether and diethyl phthalate is too low, the capacity retention cannot be significantly improved either. Furthermore, after using polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and diethyl phthalate, ethylene glycol dibutyrate can be added to further improve the battery's capacity retention.

[0086] The embodiments and / or implementation methods described above are merely preferred embodiments and / or implementation methods for implementing the technology of the present invention, and are not intended to limit the implementation methods of the technology of the present invention in any way. Any person skilled in the art can make some modifications or alterations to other equivalent embodiments without departing from the scope of the technical means disclosed in the content of the present invention, but they should still be regarded as the technology or embodiments that are substantially the same as the present invention.

[0087] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. The above descriptions are only preferred embodiments of this application. It should be noted that due to the limitations of written expression, while there are objectively infinite specific structures, those skilled in the art can make several improvements, modifications, or changes without departing from the principles of this application, and can also combine the above technical features in an appropriate manner. These improvements, modifications, changes, or combinations, or the direct application of the inventive concept and technical solution to other situations without modification, should all be considered within the scope of protection of this application.

Claims

1. A method for manufacturing a high-entropy cathode composite oxide material, comprising: Inorganic metal compounds are mixed and then pulverized. The pulverized particles are mixed with organometallic compounds and water and ball-milled. Then, phosphorus and fluorine source compounds are added and ball-milled again. Finally, sodium source compounds and granulators are added and ball-milled again to obtain a slurry. The slurry is then sand-milled, spray-dried, and calcined to obtain a cathode composite oxide material. The chemical formula of the cathode composite oxide material is: Na x M1 y M2 z O 2-1.5α-0.5β (PO4) α F β M1 is an electrochemically active metal ion, M2 is an electrochemically inactive metal ion, and x, y, z, α, and β are the molar percentages of Na, M1, M2, (PO4), and F, respectively; M1 includes Cu. 2+ Ni 2+ Mn 2 + Fe 3+ Co 3+ Cr 3+ and V 5+ At least one of the following; the M2 includes Mg 2+ Zn 2+ Zr 4+ Sn 4+ Mn 4+ Ti 4+ Mo 4+ Sb 4+ and Nb 5+ At least one of them; The inorganic metal compound includes manganese monoxide and at least one selected from copper oxide, nickel oxide, ferrous oxide, vanadium pentoxide, titanium dioxide, cobalt oxide, nickel carbonate, ferrous carbonate, manganese carbonate, chromium trioxide, and niobium pentoxide. The organometallic compound includes at least one of zinc acetate, molybdenum(II) acetate dimer, magnesium acetate, zirconium acetate, tin acetate, and antimony triacetate; The granulating agent includes at least one of polyvinyl alcohol, methyl allyl alcohol polyoxyethylene ether, and diethyl phthalate; the amount of polyvinyl alcohol used is 1-20 wt% of manganese monoxide; the amount of methyl allyl alcohol used is 0.5-3 wt% of manganese monoxide; and the amount of diethyl phthalate used is 0.4-2 wt% of manganese monoxide.

2. The method for manufacturing a high-entropy cathode composite oxide material according to claim 1, characterized in that, The pulverization process includes roller pulverization and airflow pulverization.

3. The high-entropy cathode composite oxide material prepared by the method of claim 1 or 2, wherein the general chemical formula of the high-entropy cathode composite oxide material is: Na x M1 y M2 z O 2-1.5α-0.5β (PO4) α F β M1 represents electrochemically active metal ions, M2 represents non-electrochemically active metal ions, and x, y, z, α, and β represent the molar percentages of Na, M1, M2, (PO4), and F, respectively.

4. A battery comprising the high-entropy cathode composite oxide material as described in claim 3.

Images