A copper-manganese disordered high-voltage copper-based oxide material and its application

Abstract

This invention discloses a copper-manganese disordered high-voltage copper-based oxide material and its applications. The chemical formula of this material is: Na 0.67 Cu 0.33 Mn 0.67‑x A x O2; wherein Cu has a valence state of +2, Mn has a valence state of +4, and A is one or more elements selected from Ti, Zr, Si, Ge, Sn, Hf, Pb, Ce, and Th, with 0.02≤x≤0.34 and A having a valence state of +4; in the transition metal layer, the transition metal ions are randomly arranged, causing the transition metal layer elements to migrate to the sodium layer at a voltage of 4.5V, constructing a Na-O-A configuration, and improving the energy density of the material by activating the redox reaction of oxygen. This material is used as the positive electrode of a sodium-ion secondary battery. The copper-manganese disordered high-voltage copper-based oxide material provided by this invention is simple to prepare, and the elements sodium, copper, manganese, and titanium contained therein are all non-toxic and safe elements. In this material, the redox couple itself has a high voltage. In the transition metal layer, the transition metal ions are arranged in a disordered manner, leading to the activation of the redox reaction of oxygen at high voltage.

Description

Technical Field

[0001] This invention relates to an oxide material and its application, and more particularly to a copper-manganese disordered high-voltage copper-based oxide material and its application, belonging to the field of materials technology. Background Technology

[0002] With the widespread application of lithium-ion batteries in new energy vehicles and various large-scale energy storage devices, the demand for lithium resources is increasing. Due to the limited reserves and uneven distribution of lithium resources, the cost of lithium-ion batteries is rising. Therefore, it is necessary to find a new resource to alleviate the current lithium shortage. Sodium and lithium belong to the same group and have similar chemical properties. Moreover, sodium resources are abundant, inexpensive, and non-toxic. Therefore, sodium-ion batteries can, to some extent, alleviate the problem of hindered battery development caused by lithium resource scarcity and supplement the market application of lithium-ion batteries, especially in large-scale energy storage grids. At the same time, sodium-ion batteries have high energy storage conversion efficiency and long cycle life, providing an opportunity to gradually replace lead-acid batteries.

[0003] Besides the issue of lithium resources, other elements commonly used in lithium-ion batteries, such as cobalt, nickel, and copper (negative electrode current collectors), also have relatively low reserves in the Earth's crust. In contrast, elements commonly used in sodium-ion batteries, such as iron, manganese, and aluminum (positive and negative electrode current collectors), have relatively high reserves in the Earth's crust. This has, to some extent, promoted the development of sodium-ion battery research. Especially recently, the emergence of positive electrode materials that do not contain nickel and cobalt, such as Na... x FeMnO2 and Na x CuFeMnO2 layered oxide electrode material. Because lithium and aluminum react to form a lithium-aluminum alloy, the application of aluminum foil as a current collector on the negative electrode side of lithium-ion batteries is limited. However, sodium and aluminum do not form an alloy, so aluminum foil can replace copper foil as the current collector in sodium-ion battery negative electrode materials, further reducing the cost of sodium-ion batteries. Furthermore, sodium-ion batteries and lithium-ion batteries have similar working principles and material systems, allowing the use of equipment, technologies, and methods from lithium-ion battery production in large-scale manufacturing, thus accelerating the industrialization of sodium-ion batteries.

[0004] Due to the large mass and radius of sodium ions, their migration speed in sodium storage materials is slow, which is detrimental to improving the rate performance of sodium-ion batteries and also results in lower mass / volume energy density compared to lithium-ion batteries. In traditional layered transition metal oxides, transition metals are considered the only redox centers in electrochemical reactions, and the specific capacity of cathode materials is limited by the content of variable-valence transition metals. However, recent studies have shown that in some layered transition metal oxides, anionic oxygen can also participate in electrochemical reactions. The synergistic redox reaction based on transition metals and anionic oxygen offers a possibility for improving the specific capacity of layered cathode materials. The anionic redox reaction activity was first observed in lithium-rich cathode materials with a Li-O-Li structure, producing non-bonded O 2p states. In sodium-ion batteries, this concept has been extended to layered oxide cathodes with a Na-OA structure, where the A alkali metal, alkaline earth metal, or transition metal layers have vacancies. Moreover, since the average operating voltage of most sodium-ion battery cathode materials is only around 3V, far lower than the 3.7V of ternary lithium-ion battery cathodes, this greatly limits the operating scenarios of sodium-ion batteries. Therefore, there is a need to develop more high-pressure sodium-ion battery cathode materials.

[0005] In the cathode material of high-voltage sodium-ion batteries, Na 0.67 Cu 0.33 Mn 0.67 O2 is a copper-manganese ordered high-voltage copper-based oxide material that can withstand voltages above 3.5V for metallic sodium and has a high energy density, making it suitable for large-scale applications. However, in its transition metal layer, manganese ions surround copper ions in a honeycomb-like ordered arrangement. Due to this periodic arrangement, the crystal structure has very high hardness, and the structural changes are minimal during charging and discharging. Under high voltage, it cannot activate the redox reaction of oxygen to further increase the energy density. Summary of the Invention

[0006] To address the shortcomings of the aforementioned technologies, this invention provides a copper-manganese disordered high-voltage copper-based oxide material and its application, thereby solving the problems of existing copper-manganese ordered high-voltage copper-based oxides. 0.67 Cu 0.33 Mn 0.67 The problem of O2 materials failing to activate oxygen redox reactions under high voltage.

[0007] To solve the above technical problems, the technical solution adopted by this invention is: a copper-manganese disordered high-voltage copper-based oxide material, the chemical formula of which is: Na 0.67 Cu 0.33 Mn 0.67-x A xO2; where Cu has a valence state of +2, Mn has a valence state of +4, and A is one or more elements selected from Ti, Zr, Si, Ge, Sn, Hf, Pb, Ce, and Th, with 0.02≤x≤0.34 and A having a valence state of +4;

[0008] In the transition metal layer, the transition metal ions are arranged in a disordered manner. At a voltage of 4.5V, the transition metal layer elements migrate to the sodium layer to construct the Na-OA configuration, and improve the energy density of the material by activating the redox reaction of oxygen.

[0009] Preferably, the average working voltage of the copper-manganese disordered high-voltage copper-based oxide material is above 4.25V relative to that of metallic sodium.

[0010] A positive electrode for a sodium-ion secondary battery, comprising: a current collector, a conductive additive and a binder coated on the current collector, and a copper-manganese disordered high-voltage copper-based oxide material.

[0011] A sodium-ion secondary battery comprising the aforementioned positive electrode.

[0012] Preferably, sodium-ion secondary batteries are used in any one of the following: large-scale energy storage devices for solar and wind power generation, or energy storage devices for smart grid peak shaving, distributed power stations, backup power supplies, communication base stations, and electric vehicles.

[0013] This invention is mainly based on the redox reaction of copper and oxygen and the disordered copper-manganese cathode material structure, which enables the material to activate the redox reaction of oxygen when operating above 4.25V, thereby improving the reversible capacity and energy density.

[0014] In the transition metal layer, transition metal ions are arranged in a disordered manner to reduce the hardness of the crystal structure when arranged in an ordered manner. This facilitates interlayer sliding between transition metal layers under high voltage. Interlayer sliding generates octahedral sites within the sodium layer, allowing transition metal ions to migrate from the transition metal layer to the Na layer via an octahedral-tetrahedral-octahedral pathway, creating vacancies within the transition metal layer. This process produces a new Na-OA configuration, activating the reversible oxygen redox reaction and improving reversible capacity and energy density.

[0015] The copper-manganese disordered high-voltage copper-based oxide material provided by this invention is simple to prepare, and the contained elements sodium, copper, manganese, and titanium are all non-toxic and safe. In this material, the copper redox couple itself has a high voltage. In the transition metal layer, the transition metal ions are arranged in a disordered manner, leading to the activation of oxygen redox reactions under high voltage. The charging capacity is its theoretical capacity, with stable cycling, excellent rate performance, and high safety. The required elements are abundant in the Earth's crust, and the raw materials used are inexpensive, making it green, energy-saving, and environmentally friendly.

[0016] This invention provides an application of sodium-ion secondary batteries, which are used in large-scale energy storage devices for solar and wind power generation, or in energy storage devices for smart grid peak shaving, distributed power stations, backup power supplies, communication base stations, and electric vehicles. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of the material of the present invention;

[0018] Figure 2 The X-ray diffraction (XRD) patterns of the cathode materials of Examples 1-5 of this invention are shown below.

[0019] Figure 3 Selected area electron diffraction image of transmission electron microscopy according to Embodiment 1 of the present invention;

[0020] Figure 4 This is a curve showing the fitting of the distribution function to Embodiment 1 of the present invention;

[0021] Figure 5 The charge-discharge curve of the sodium-ion battery provided in Embodiment 1 of the present invention at 2-4.5V;

[0022] Figure 6 The copper-manganese disordered material Na provided in Embodiment 1 of the present invention 2 / 3 Cu 1 / 3 Mn 1 / 2 Ti 1 / 6 O2 and Na 0.67 Cu 0.33 Mn 0.67 Comparison of O2 charge / discharge curves at 2-4.5V;

[0023] Figure 7 The copper-manganese disordered material Na provided in Embodiment 1 of the present invention 2 / 3 Cu 1 / 3 Mn 1 / 2 Ti 1 / 6 O2 and Na 0.67 Cu 0.33 Mn 0.67 Aberration-corrected transmission electron microscope image of O2 in a 4.5V charging state;

[0024] Figure 8 The X-ray absorption spectrum of the 0 K-edge (K edge of oxygen) of the sodium-ion battery provided in Embodiment 1 of the present invention during the 2-4.5V charge-discharge process;

[0025] Figure 9 The charge-discharge curve of the sodium-ion battery provided in Embodiment 2 of the present invention at 2-4.5V;

[0026] Figure 10The charge-discharge curve of the sodium-ion battery provided in Embodiment 3 of the present invention at 2-4.5V;

[0027] Figure 11 The charge-discharge curve of the sodium-ion battery provided in Embodiment 6 of the present invention is shown in the range of 2-4.5V. Detailed Implementation

[0028] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0029] This invention proposes a copper-manganese disordered high-voltage copper-based oxide material, the chemical formula of which is: Na 0.67 Cu 0.33 Mn 0.67-x A x O2; where Cu has a valence state of +2, Mn has a valence state of +4, and A is one or more elements with a valence state of +4, such as Ti, Zr, Si, Ge, Sn, Hf, Pb, Ce, and Th, with a valence of 0.02 ≤ x ≤ 0.34; in the transition metal layer, the transition metal ions are arranged in a disordered manner, with the specific structure as follows: Figure 1 As shown, the TM layer represents a disordered arrangement of any one of copper, manganese, or alumina. This disordered arrangement can reduce the hardness of the crystal structure when ordered, allowing transition metal elements to migrate to the sodium layer, constructing a Na-OA configuration, activating the redox reaction of oxygen, and increasing the energy density.

[0030] During the first week of charging, copper ions lose electrons, and their valence changes completely from +2 to +3. Oxygen ions lose electrons and their valence changes from -2. During the first week of discharging, copper ions and oxygen ions regain electrons and return to +2 and -2 valences, respectively.

[0031] Example 1

[0032] In this embodiment, disordered copper-manganese high-voltage copper-based oxide materials are prepared using a solid-state method.

[0033] NaNO3 (analytical grade), CuO (analytical grade), MnO2 (analytical grade), and TiO2 (analytical grade) were mixed in the required stoichiometric ratio; the mixture was ground in an agate mortar for 20 minutes to obtain a precursor; the precursor was pressed into tablets and transferred to an alumina crucible, and treated in a muffle furnace at 950°C for 15 hours (heating rate of 5°C / min) to obtain a black powder of layered oxide material Na. 2 / 3Cu 1 / 3 Mn 1 / 2 Ti 1 / 6 O2, its X-ray diffraction pattern can be found in [reference needed]. Figure 2 From the X-ray diffraction pattern, Na 2 / 3 Cu 1 / 3 Mn 1 / 2 Ti1 / The crystal structure of 6O2 is a layered oxide of the P2 phase with no superlattice peaks, proving that it is a disordered transition metal structure. Figure 3 The selected area electron diffraction image from the transmission electron microscope shown indicates that there are no diffraction spots generated by the superlattice structure in the (100) crystal orientation, further proving that it is a disordered structure of transition metal.

[0034] Na was collected using Ag target X-rays. 2 / 3 Cu 1 / 3 Mn 1 / 2 Ti 1 / 6 The distribution function data of O2 were analyzed using PDFgui software, such as... Figure 4 As shown in the figure, the black line represents the logarithmic distribution function data obtained from the test, the red line represents the fitting curve obtained using PDFgui software, and the blue line represents the error value between the experiment and the fitting. Figure a shows the ordered space group P63 of the transition metal layer, and Figure b shows the disordered space group P63 / mmc of the transition metal layer. Within the short-range structure, the R-factor obtained by fitting the structure using the ordered space group P63 of the transition metal layer reaches 37.5%, while the R-factor obtained by fitting it using the disordered space group P63 / mmc of the transition metal layer is only 15.2%, proving that the short-range structure is disordered, further proving that it is a disordered structure of transition metal.

[0035] A sodium-ion battery was prepared using the above-mentioned copper-manganese disordered high-voltage copper-based oxide as the positive electrode material. Specific steps: The prepared active material Na... 2 / 3 Cu 1 / 3 Mn 1 / 2 Ti 1 / 6 O2 powder, conductive carbon black, and polyvinylidene fluoride (PVDF) binder are mixed in a mass ratio of 80:10:10. An appropriate amount of N-methylpyrrolidone (NMP) solution is added, and the mixture is stirred into a uniform slurry using a degassing machine in a dry environment at room temperature. The slurry is then uniformly coated onto current collector aluminum foil and dried in a forced-air drying oven at 70°C. The resulting material is then cut into 10mm diameter circular electrode sheets. These sheets are dried under vacuum at 120°C for 6 hours and then transferred to a glove box for later use.

[0036] The simulated battery assembly was performed in an Ar atmosphere glove box, using metallic sodium as the counter electrode and a 1 mol NaClO4 solution dissolved in ethylene carbonate (EC) + diethyl carbonate (DEC) (volume ratio 1:1) as the electrolyte. A CR2032 button cell was assembled. Charge-discharge tests were conducted using a constant current charge-discharge mode, with the first cycle performed at a 0.1C current density within a 2-4.5V voltage range. The results are as follows. Figure 5 As shown, the charging specific capacity reaches over 130mAh / g, the discharging specific capacity reaches over 150mAh / g, and the curve is smooth.

[0037] Figure 6 Na is a copper-manganese disordered material 2 / 3 Cu 1 / 3 Mn 1 / 2 Ti 1 / 6 O2 and Ordered Copper-Based Materials

[0038] Na 0.67 Cu 0.33 Mn 0.67 Comparison of the electrochemical performance of O2. Ordered copper-based materials Na 0.67 Cu 0.33 Mn 0.67 O2 can only achieve a specific capacity of 93 mAh / g during charging. Since the Mn ions are in the +4 valence state, only Cu ions can undergo Cu... 2+ / Cu 3+ The redox reaction yielded a charging capacity consistent with the theoretical capacity of copper redox. Furthermore, it contributed almost no specific capacity at high voltages above 4V, proving its inability to activate the oxygen redox reaction. Copper-manganese disordered material Na... 2 / 3 Cu 1 / 3 Mn 1 / 2Ti 1 / 6 During the charging process, it can be seen that when O2 is used at a voltage of ≥4.25V, it produces an additional smooth curve compared to copper-based materials, and the resulting specific capacity far exceeds the theoretical specific capacity that copper and manganese in the material can obtain.

[0039] like Figure 7 As shown, aberration-corrected scanning electron microscopy reveals that the ordered copper-based material Na in Figure a... 0.67 Cu 0.33 Mn 0.67 When O2 is charged to 4.5V, its highly ordered crystal structure prevents transition metal atoms from migrating to the sodium layer. In contrast, the disordered copper-manganese material Na in Figure b... 2 / 3 Cu 1 / 3 Mn 1 / 2 Ti 1 / 6 When O2 is charged to 4.5V, transition metal atoms can migrate, leaving vacancies in the transition metal layer to build the Na-OA configuration and activate the redox reaction of oxygen to improve the energy density of the material.

[0040] like Figure 8As shown, the OK-edge under different charged states was measured by X-ray absorption spectroscopy. The oxygen redox reaction is hidden in the leading edge of the OK-edge spectrum. Since the density of empty bound states above the molecular energy level is related to the hybridization of the metal's 3d-O-2p orbitals, the intensity of the edge peak as a function of electrochemical insertion / extraction can provide information about the distribution of oxygen atom vacancy states and effective charge. As can be seen from the figure, the intensity of the OK-edge decreases from the uncharged state to the 4.25V state, proving that this voltage range represents a copper ion redox reaction. 2+ Oxidized to Cu 3+ The covalent strength between copper and oxygen ions increases. However, during the charging process from 4.25V to 4.5V, the strength of the O K-edge actually increases, proving that this voltage range represents the redox reaction of oxygen. 2- Oxidized to O n- The increased number of oxygen vacancies leads to a higher intensity of the OK-edge. This demonstrates that it can activate the oxygen redox reaction, which exhibits a smooth curve above 4.2V during charging, with an average voltage of 3.72V, exceeding that of most layered oxide cathodes, and further improving the material's energy density.

[0041] Example 2

[0042] In this embodiment, disordered copper-manganese high-voltage copper-based oxide materials are prepared using a solid-state method.

[0043] The stoichiometry of NaNO3 (analytical grade), CuO (analytical grade), MnO2 (analytical grade), and TiO2 (analytical grade) differed from that in Example 1. The heat treatment conditions were 950°C for 15 hours, resulting in a black powdery layered oxide material, Na. 0.67 Cu 0.33 Mn 0.65 Ti 0.08 For the X-ray diffraction pattern of O2, please refer to [reference needed]. Figure 2 From the X-ray diffraction pattern, Na 0.67 Cu 0.33 Mn 0.65 Ti 0.08 O2 has a crystal structure of a P2 phase layered transition metal disordered oxide.

[0044] The aforementioned copper-manganese disordered high-voltage copper-based oxide was used as the positive electrode material in the preparation of a sodium-ion battery, and electrochemical charge-discharge tests were conducted. The preparation process and testing methods were the same as in Example 1. The test voltage range was 2V-4.5V, and the test results are shown in [Figure 1]. Figure 8It can be seen that when used at a voltage of ≥4.25V, it will generate an additional smooth curve. The obtained specific capacity far exceeds the theoretical specific capacity that copper and manganese in the material can obtain, and it can activate the oxidation-reduction reaction of oxygen. The specific capacity of the first charge can reach 118mAh / g, with an average operating voltage of 3.82V.

[0045] Example 3

[0046] In this embodiment, disordered copper-manganese high-voltage copper-based oxide materials are prepared using a solid-state method.

[0047] The stoichiometry of NaNO3 (analytical grade), CuO (analytical grade), MnO2 (analytical grade), and TiO2 (analytical grade) differed from that in Example 1. The heat treatment conditions were 950°C for 15 hours, resulting in a black powdery layered oxide material, Na. 0.67 Cu 0.33 Mn 0.59 Ti 0.25 For the X-ray diffraction pattern of O2, please refer to [reference needed]. Figure 2 From the X-ray diffraction pattern, Na 0.67 Cu 0.33 Mn 0.59 Ti 0.25 O2 has a crystal structure of a P2 phase layered transition metal disordered oxide.

[0048] The aforementioned copper-manganese disordered high-voltage copper-based oxide was used as the positive electrode material in the preparation of a sodium-ion battery, and electrochemical charge-discharge tests were conducted. The preparation process and testing methods were the same as in Example 1. The test voltage range was 2V-4.5V, and the test results are shown below. Figure 9 It can be seen that when used at a voltage of ≥4.25V, an additional smoothing curve is generated. The obtained specific capacity far exceeds the theoretical specific capacity that copper and manganese in the material can achieve. It can activate the redox reaction of oxygen, and the first-week charge specific capacity can reach 121mAh / g, with an average operating voltage of 3.82V.

[0049] Example 4

[0050] In this embodiment, disordered copper-manganese high-voltage copper-based oxide materials are prepared using a solid-state method.

[0051] The stoichiometry of NaNO3 (analytical grade), CuO (analytical grade), MnO2 (analytical grade), and TiO2 (analytical grade) differed from that in Example 1. The heat treatment conditions were 950°C for 15 hours, resulting in a black powdery layered oxide material, Na. 0.67 Cu 0.33 Mn 0.42 Ti 0.02 For the X-ray diffraction pattern of O2, please refer to [reference needed]. Figure 2 From the X-ray diffraction pattern, Na0.67 Cu 0.33 Mn 0.42 Ti 0.02 O2 has a crystal structure of a P2 phase layered transition metal disordered oxide.

[0052] Example 5

[0053] In this embodiment, disordered copper-manganese high-voltage copper-based oxide materials are prepared using a solid-state method.

[0054] The stoichiometry of NaNO3 (analytical grade), CuO (analytical grade), MnO2 (analytical grade), and TiO2 (analytical grade) differed from that in Example 1. The heat treatment conditions were 950°C for 15 hours, resulting in a black powdery layered oxide material, Na. 0.67 Cu 0.33 Mn 0.33 Ti 0.33 For the X-ray diffraction pattern of O2, please refer to [reference needed]. Figure 2 From the X-ray diffraction pattern, Na 0.67 Cu 0.33 Mn 0.33 Ti 0.33 O2 has a crystal structure of a P2 phase layered transition metal disordered oxide.

[0055] Example 6

[0056] In this embodiment, disordered copper-manganese high-voltage copper-based oxide materials are prepared using a solid-state method.

[0057] The stoichiometry of NaNO3 (analytical grade), CuO (analytical grade), MnO2 (analytical grade), and ZrO2 (analytical grade) differed from that in Example 1. The heat treatment conditions were 950°C for 15 hours, resulting in a black powdery layered oxide material, Na. 0.67 Cu 0.33 Mn 0.59 Zr 0.08 O2.

[0058] The aforementioned copper-manganese disordered high-voltage copper-based oxide was used as the positive electrode material in the preparation of a sodium-ion battery, and electrochemical charge-discharge tests were conducted. The preparation process and testing methods were the same as in Example 1. The test voltage range was 2V-4.5V, and the test results are shown in [Figure 1]. Figure 10 It can be seen that when used at a voltage of ≥4.25V, an additional smoothing curve is generated. The obtained specific capacity far exceeds the theoretical specific capacity that copper and manganese in the material can achieve. It can activate the redox reaction of oxygen, and the specific capacity of the first charge can reach 133mAh / g, with an average operating voltage of 3.56V.

[0059] This invention provides a copper-manganese disordered high-voltage copper-based oxide material, which is not only simple to prepare, but also contains non-toxic and safe elements such as sodium, copper, manganese, and titanium. In this material, the copper redox couple itself has a high voltage. The transition metal layer has a disordered arrangement of metal ions, which reduces the lattice strength of an ordered arrangement. Under high voltage, the transition metal layer elements can migrate to the sodium layer, constructing a Na-OA configuration. When used at voltages ≥4.25V, the redox reaction of oxygen can be activated, increasing the material's energy density. These two aspects effectively improve the overall operating voltage of the material, thereby increasing its specific energy. In sodium half-cell tests, the operating potential of the copper redox reaction can reach above 3.65V, comparable to lithium-ion batteries, and exhibits excellent cycle stability, demonstrating significant practical value. Sodium-ion secondary batteries using this invention's copper-manganese disordered high-voltage copper-based oxide material can be used in large-scale energy storage devices for solar and wind power generation, or in smart grid peak shaving, distributed power stations, backup power supplies, communication base stations, and electric vehicle energy storage devices.

[0060] The above embodiments are not intended to limit the present invention, and the present invention is not limited to the examples given above. Any changes, modifications, additions or substitutions made by those skilled in the art within the scope of the technical solution of the present invention are also within the protection scope of the present invention.

Claims

1. A copper-manganese disordered high-voltage copper-based oxide material, characterized in that: The chemical general formula of the material is: Na 0.67 Cu 0.33 Mn 0.67-x A x O2; wherein, the valence of Cu is +2, the valence of Mn is +4, A is one or more elements selected from Ti, Zr, Si, Ge, Sn, Hf, Pb, Ce, Th, 0.02≤x≤0.34, and the valence of A is +4. In the transition metal layer, transition metal ions are arranged in disorder, which makes transition metal elements in the transition metal layer migrate to the sodium layer at a voltage of 4.25 V, builds a Na-O-A configuration, and improves the energy density of the material through the redox reaction of activated oxygen.

2. The copper-manganese disordered high-voltage copper-based oxide material of claim 1, wherein: The average working voltage of the copper-manganese disordered high-voltage copper-based oxide material relative to metallic sodium is above 4.25 V.

3. A positive electrode sheet of a sodium-ion secondary battery, characterized by: The positive electrode plate comprises a current collector, a conductive additive and a binder coated on the current collector, and the copper-manganese disordered high-voltage copper-based oxide material according to any one of claims 1-2.

4. A sodium-ion secondary battery comprising the positive electrode plate according to claim 3.

5. The sodium-ion secondary battery according to claim 4, characterized in that: The sodium-ion secondary battery is used in any one of the following: large-scale energy storage equipment for solar and wind power generation, smart grid peak shaving, distributed power stations, backup power sources, communication base stations, and energy storage equipment for electric vehicles. The sodium-ion secondary battery is used in any one of the following: large-scale energy storage equipment for solar and wind power generation, smart grid peak shaving, distributed power stations, backup power sources, communication base stations, and energy storage equipment for electric vehicles.

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