A non-phase-change dual-phase high-entropy oxide negative electrode material, a preparation method and application thereof

Abstract

The application discloses a non-phase-change two-phase high-entropy oxide negative material, a preparation method and application, and relates to the technical field of lithium batteries; the high-entropy oxide negative material is an oxide containing five metal elements, the five metal elements are selected from any four of magnesium, manganese, cobalt, chromium, zinc and iron and vanadium, and the molar ratio between the five metal elements is (1-3):(1-3):(1-3):(1-3):(1-3); the high-entropy oxide negative material simultaneously contains a tetragonal system and a spinel phase with three-dimensional pores, and the phase proportion of the spinel phase is 65-75%; the negative material does not change in phase during the charging and discharging process, reduces the volume strain in the charging and discharging process, makes the lithium battery have excellent long cycle performance, and improves the cycle life and stability of the lithium battery.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of lithium batteries, in particular to a phase-change-free dual-phase high-entropy oxide negative electrode material, a preparation method and applications. BACKGROUND

[0002] With the rapid development of high-entropy materials, the concept of high-entropy provides a new way for traditional negative electrode materials to solve the current dilemma. Due to the large number of elements and different atomic radii, HEM has four effects, namely high-entropy effect in thermodynamics, lattice distortion effect in structure, cocktail effect in performance and hysteresis diffusion effect in dynamics. Thanks to the four effects, high-entropy negative electrode shows excellent electrochemical performance, good corrosion resistance, high mechanical strength, etc.

[0003] In 2018, Abhishek Sarkar et al. first reported the use of high-entropy oxide (Co 0.2 Cu 0.2 Mg 0.2 Ni0 .2 Zn 0.2 )O as a lithium battery negative electrode material, and revealed the lithium storage mechanism of the material, opening a new chapter for negative electrode materials. In 2020, Hong Chen et al. reported a new spinel structure (Mg 0.2 Ti 0.2 Zn 0.2 Cu 0.2 Fe 0.2 )3O4 negative electrode material prepared by solid phase method. The material as a lithium battery negative electrode material can have a specific capacity of 272 mAh / g at a current density of 2 A / g, showing excellent electrochemical performance. In the same year, Jinhua Yan et al. first published a high-entropy oxide [(Bi,Na) 1 / 5 (La,Li) 1 / 5 (Ce,K) 1 / 5 Ca 1 / 5 Sr 1 / 5 ]TiO3 with perovskite structure. The lithium battery negative electrode material has a specific capacity of 120.4 mAh / g after 300 cycles at a current density of 1 A / g.

[0004] Although there have been reports of high-entropy negative electrode materials, the high-entropy oxide negative electrode material still has a large volume strain, resulting in poor cycle life. SUMMARY

[0005] The present application aims to solve the technical problem that the high-entropy oxide negative material still has a large volume strain, resulting in poor cycle life, and provide a phase-change-free dual-phase high-entropy oxide negative material, a preparation method and application, which has no phase change in the charging and discharging process, reduces the volume strain in the charging and discharging process, and makes the lithium battery have excellent long cycle performance and improves the cycle life and stability of the lithium battery.

[0006] The present application is realized by the following technical scheme:

[0007] The first object of the present application is to provide a phase-change-free dual-phase high-entropy oxide negative material, which is an oxide containing five metal elements, and the five metal elements are selected from any four of magnesium, manganese, cobalt, chromium, zinc, iron and vanadium, and the molar ratio of the five metal elements is (1-3):(1-3):(1-3):(1-3):(1-3).

[0008] The high-entropy oxide negative material contains tetragonal and spinel phases with three-dimensional pores, and the phase proportion of the spinel phase is 65-75%.

[0009] As a preferred embodiment, the high-entropy oxide negative material is an oxide containing five metal elements of magnesium, cobalt, chromium, manganese and vanadium, and the molar ratio of magnesium, manganese, cobalt, chromium and vanadium is (1-3):(1-3):(1-3):(1-3):(1-3), more preferably 1:(1-2):1:1:1, and most preferably 1:1:1:1:1.

[0010] As a preferred embodiment, the high-entropy oxide negative material is an oxide containing five metal elements of zinc, iron, chromium, manganese and vanadium, and the molar ratio of zinc, iron, chromium, manganese and vanadium is (1-2):(1-3):(1-3):(1-3):(1-3), more preferably 1:1:1:1:1.

[0011] Further, the particle size of the high-entropy oxide negative material is 0.2-1 μm.

[0012] The second object of the present application is to provide a preparation method of a phase-change-free dual-phase high-entropy oxide negative material, which comprises the following steps:

[0013] The metal salt and anhydrous citric acid are weighed according to the molar ratio and dissolved in deionized water or a mixture of deionized water and ethanol to form a uniform and stable sol or a precipitate by reaction; wherein the metal salt is a mixture of metal salts of any four elements of magnesium, manganese, cobalt, chromium, zinc and iron and a metal salt of vanadium;

[0014] The sol or precipitate is dried and ground to obtain a precursor powder;

[0015] The precursor powder is sintered, heat preserved, and cooled to room temperature with the furnace, so that a phase-change-free dual-phase high-entropy oxide negative material is obtained.

[0016] Further, the molar ratio of the metal salt to anhydrous citric acid is 5:(1-4).

[0017] Further, the drying temperature of the sol or the precipitate is 140-160 DEG C.

[0018] Further, the sintering and heat preservation of the precursor powder specifically comprises:

[0019] The pre-sintering is performed at 400-500 DEG C, the heating rate is 5-10 DEG C / min, and the heat preservation is 100-130 min, so that the pre-sintered powder is obtained;

[0020] The pre-sintered powder is ground and subjected to secondary sintering at 750-850 DEG C, and the heat preservation is 100-130 min.

[0021] The third object of the present application is to provide an application of the phase-change-free dual-phase high-entropy oxide negative material in a lithium ion battery negative material.

[0022] Based on the above application, the present application further provides a lithium ion battery, which comprises a positive electrode, a negative electrode, an electrolyte and a separator, and the negative electrode comprises the phase-change-free dual-phase high-entropy oxide negative material.

[0023] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0024] The phase-change-free dual-phase high-entropy oxide negative material of the present application simultaneously comprises a tetragonal system (Cmca phase) with three-dimensional pores and a spinel phase (Fd-3m phase) with excellent stable structure, and no phase change occurs during the charging and discharging process, so that the volume strain during the charging and discharging process is reduced, the lithium battery has excellent long cycle performance, and the cycle life and stability of the lithium battery are improved. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical scheme in the exemplary embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments, and it should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings. In the drawings:

[0026] Figure 1 The XRD diffraction pattern of the phase-change-free dual-phase high-entropy oxide prepared for Example 1;

[0027] Figure 2 The micro-morphology diagram of the phase-change-free dual-phase high-entropy oxide prepared for Example 1;

[0028] Figure 3 Long cycle chart of the phase transition-free dual-phase high-entropy oxide prepared for Example 1 at a current density of 2 A / g;

[0029] Figure 4 Long cycle chart of the phase transition-free dual-phase high-entropy oxide anode material prepared for Example 1 at a high temperature of 60°C at a current density of 1 A / g;

[0030] Figure 5 XRD diffraction peak change chart of the phase transition-free dual-phase high-entropy oxide anode material prepared for Example 1 during the charging and discharging process;

[0031] Figure 6 Microscopic morphology chart of the phase transition-free dual-phase high-entropy oxide prepared for Example 2;

[0032] Figure 7 Microscopic morphology chart of the phase transition-free dual-phase high-entropy oxide prepared for Example 3. DETAILED DESCRIPTION

[0033] In order to make the objects, technical solutions and advantages of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the embodiments and drawings. Obviously, the illustrative embodiments of the present application and their descriptions are only used to explain the present application and should not be used as a limitation of the present application.

[0034] The embodiments of the phase transition-free dual-phase high-entropy oxide anode material, preparation method and application of the present application will be described in detail below with appropriate reference to the drawings. However, there will be cases of omitting unnecessary detailed descriptions. For example, there will be cases of omitting detailed descriptions and repeated descriptions of matters that are well known. This is to avoid the following description from becoming unnecessarily lengthy and to facilitate the understanding of those skilled in the art.

[0035] The ranges disclosed in the present application are limited in the form of lower and upper limits, and a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of a particular range. The ranges defined in this way can include or not include the end values, and can be arbitrarily combined, i.e., any lower limit can be combined with any upper limit to form a range.

[0036] If not specifically stated, all embodiments and optional embodiments of the present application can be combined with each other to form new technical solutions.

[0037] If not specifically stated, all technical features and optional technical features of the present application can be combined with each other to form new technical solutions.

[0038] If there is no special description, the "including" and "containing" mentioned in the application means open, and can also be closed. For example, the "including" and "containing" can mean that other substances not listed can also be included or contained, or only the listed substances can be included or contained.

[0039] If there is no special description, all the steps of the application can be carried out in sequence or randomly, preferably in sequence.

[0040] Based on the technical problem that the current high-entropy oxide negative material still has a large volume strain, resulting in poor cycle life, the application provides a phase-change-free dual-phase high-entropy oxide negative material, the high-entropy oxide negative material is an oxide containing five metal elements, the five metal elements are selected from any four of magnesium, manganese, cobalt, chromium, zinc, iron and vanadium, and the molar ratio between the five metal elements is (1-3):(1-3):(1-3):(1-3):(1-3).

[0041] The high-entropy oxide negative material simultaneously contains tetragonal system and spinel phase with three-dimensional pores, and the phase proportion of the spinel phase is 65-75%.

[0042] It should be noted that the molar ratio between the five metal elements is (1-3):(1-3):(1-3):(1-3):(1-3), which means, for example, that the molar amount of any one of magnesium, manganese, cobalt, chromium, zinc, iron and vanadium can be selected between 1-3 moles based on 1 mole as the basic amount, and all can achieve the technical effect of the application.

[0043] The phase-change-free dual-phase high-entropy oxide negative material of the application simultaneously contains tetragonal system (Cmca phase) with three-dimensional pores along the C axis and spinel phase (Fd-3m phase) with excellent stable structure, the three-dimensional voids in the Cmca phase have a diagonal length of The Fd-3m is composed of oxygen tetrahedron and oxygen octahedron, and has a stable structure. After the tetragonal system Cmca phase and the spinel phase Fd-3m form a dual-phase heterogeneous structure, the three-dimensional voids in the Cmca phase are beneficial to the transmission and storage of Li+, and the Fd-3m with stable structure is beneficial to buffering volume strain and maintaining the integrity of active particles during charging and discharging. Therefore, the dual-phase heterogeneous structure formed by the tetragonal system Cmca phase and the spinel phase Fd-3m can effectively reduce the volume strain, improve the material conductivity and cycle stability.

[0044] The phase-change-free dual-phase high-entropy oxide negative material of the application has almost no change in crystal structure during charging and discharging, and the cell volume change rate is 0.63%, which has excellent long cycle performance during charging and discharging, and effectively improves the cycle life of lithium ion batteries when applied to lithium ion battery negative electrodes.

[0045] In one or more embodiments, the high-entropy oxide negative electrode material is an oxide containing five metal elements of magnesium, cobalt, chromium, manganese and vanadium, and the molar ratio of magnesium, manganese, cobalt, chromium and vanadium is (1-3):(1-3):(1-3):(1-3):(1-3), more preferably 1:(1-2):1:1:1, and most preferably 1:1:1:1:1.

[0046] In one or more embodiments, the high-entropy oxide negative electrode material is an oxide containing five metal elements of zinc, iron, chromium, manganese and vanadium, and the molar ratio of zinc, iron, chromium, manganese and vanadium is (1-2):(1-3):(1-3):(1-3):(1-3), more preferably 1:1:1:1:1.

[0047] In one or more embodiments, the particle size of the high-entropy oxide negative electrode material is in the range of 0.2-1 μm.

[0048] The present application also provides a preparation method of the phase-change-free two-phase high-entropy oxide negative electrode material, comprising the following steps:

[0049] (1) metal salts and anhydrous citric acid are weighed according to the molar ratio, dissolved in deionized water or a mixture of deionized water and ethanol to obtain a mixed solution, and then magnetically stirred at 100-110°C for 110-130 min to form a uniform and stable sol;

[0050] or the mixed solution is placed in a high-temperature reaction kettle and incubated at 170-190°C for 10-15 hours to obtain a precipitate;

[0051] wherein the metal salts are a mixture of metal salts of any 4 elements of magnesium, manganese, cobalt, chromium, zinc and iron and metal salts of vanadium, and the molar ratio of the metal salts to anhydrous citric acid is 5:(1-4), for example, the molar ratio of the metal salts to anhydrous citric acid can be 5:4, 4:1 or 5:2.

[0052] (2) the obtained sol is placed in a drying box and dried at 140-160°C to obtain a precursor gel, and the dried gel is ground to obtain a precursor powder;

[0053] or the precipitate is centrifuged and washed with deionized water and ethanol, then dried at 100-110°C, and then the dried powder is ground to obtain a precursor powder;

[0054] wherein the drying temperature of the sol is preferably 150°C, and the drying temperature of the precipitate is preferably 100°C.

[0055] (3) the precursor powder is pre-sintered at 400-500 DEG C, the heating rate is 5-10 DEG C / min, the holding time is 100-130 min, the pre-sintered powder is obtained, the pre-sintered powder is ground, and the second sintering is carried out at 750-850 DEG C, the holding time is 100-130 min, and the furnace is cooled to room temperature, so that the phase-change-free dual-phase high-entropy oxide negative electrode material is obtained.

[0056] The application further provides application of the phase-change-free dual-phase high-entropy oxide negative electrode material in a lithium ion battery negative electrode material.

[0057] Based on the above application, the application further provides a lithium ion battery, which comprises a positive electrode, a negative electrode, an electrolyte and a separator, and the negative electrode comprises the phase-change-free dual-phase high-entropy oxide negative electrode material.

[0058] The technical scheme of the application is further described in detail in combination with examples.

[0059] It should be noted that, unless otherwise specified, the experimental methods used in the examples are all conventional methods. The materials, reagents, methods and instruments used, unless otherwise specified, are all conventional materials, reagents, methods and instruments in the art, which can be obtained by commercial channels by those skilled in the art.

[0060] Example 1

[0061] A preparation method of a phase-change-free dual-phase high-entropy oxide negative electrode material comprises the following steps:

[0062] (1) magnesium acetate, manganese acetate, cobalt acetate, chromium chloride, ammonium metavanadate and anhydrous citric acid are dissolved in a proper amount of deionized water to form a solution, the solution is magnetically stirred at 100 DEG C for 120 min to form a uniform and stable sol, the prepared sol is placed in a drying oven and dried at 150 DEG C to obtain a brown precursor gel, and the dried gel is ground to obtain a precursor powder.

[0063] (2) the precursor powder is pre-sintered at 400 DEG C, the heating rate is 10 DEG C / min, the holding time is 120 min, the pre-sintered powder is obtained, the pre-sintered powder is ground, the second sintering is carried out at 800 DEG C, the holding time is 120 min, and the furnace is cooled to room temperature, so that the phase-change-free dual-phase high-entropy oxide negative electrode material is obtained.

[0064] The XRD diffraction pattern of the phase-change-free dual-phase high-entropy oxide negative electrode material prepared in the example is shown in Figure 1 Figure 1 ​It can be seen that the XRD diffraction peaks of the non-phase-transition dual-phase high-entropy oxide correspond to the two standard card directions. The diffraction peaks marked in red belong to the tetragonal system (Cmca phase), and the blue ones belong to the spinel phase (Fd-3m). The XRD diffraction results indicate that this example successfully prepared a non-phase-transition dual-phase high-entropy oxide negative electrode material with Cmca and Fd-3m phases.

[0065] The micromorphology of the non-phase-change dual-phase high entropy oxide negative electrode material prepared in this embodiment is shown in FIG. Figure 2 As shown, from Figure 2 It can be seen that the average particle size of the non-phase-change dual-phase high-entropy oxide negative electrode material prepared in this embodiment is 0.5 μm.

[0066] The non-phase-change dual-phase high-entropy oxide negative electrode material prepared in this example was mixed with conductive carbon black and a binder in a mass ratio of 7:2:1 and coated on a copper current collector. The mixture was then cut into electrode discs with a diameter of 12 mm using a cutting machine. The electrode discs were then assembled with gaskets, springs, steel sheets, and positive and negative electrode shells into button cells for electrochemical testing. The results are as follows:

[0067] 1. The long cycle diagram of the phase-change-free dual-phase high entropy oxide negative electrode material at a current density of 2A / g is shown in the figure below. Figure 3 As shown, from Figure 3 It can be seen that after the phase-change-free dual-phase high-entropy oxide negative electrode material of this embodiment is cycled 1000 times at 2 A / g, the reversible capacity remains at 162.3 mAh / g, and has good cycle life and stability.

[0068] 2. The long cycle diagram of the non-phase-change dual-phase high entropy oxide negative electrode material at a high temperature of 60°C and a current density of 1A / g is shown in the figure below. Figure 4 As shown, from Figure 4 It can be seen that the phase-change-free dual-phase high-entropy oxide negative electrode material of this embodiment still maintains a reversible capacity of 464 mAh / g after 500 charge and discharge cycles at 1 A / g under high temperature conditions of 60°C, and still has good cycle life and stability at high temperatures.

[0069] 3. The XRD diffraction peak change diagram of the non-phase-change dual-phase high entropy oxide negative electrode material during the charge and discharge process is as follows Figure 5 As shown, in Figure 5 In the figure, the green XRD data shows the change in the diffraction peak of the negative electrode material during discharge, and the purple XRD data shows the change in the diffraction peak of the negative electrode during charging. As can be seen from the figure, there is no significant change in the XRD diffraction peak during the charge and discharge process, indicating that the negative electrode material does not undergo phase change during the charge and discharge process, thereby reducing the volume strain during the charge and discharge process and ensuring the long cycle life and high stability of the lithium battery.

[0070] Example 2

[0071] A preparation method of a non-phase-change dual-phase high-entropy oxide negative electrode material, comprising the following steps:

[0072] (1) Dissolve magnesium acetate, manganese acetate, cobalt acetate, chromium chloride, and ammonium metavanadate in a molar ratio of 1:2:1:1:1 in an appropriate amount of ethanol to form solution A, and dissolve citric acid in a molar ratio of 1:4 with the metal salt in 20 mL of deionized water to form stable solution B.

[0073] (2) Mix solution A and solution B uniformly and place them in a high-temperature reaction kettle, and keep the temperature at 180°C for 12 hours to obtain black precipitate. The black precipitate is washed by centrifugation with deionized water and ethanol, and then dried at 100°C. The precursor powder is obtained by grinding.

[0074] (3) The precursor powder is pre-sintered at 400°C with a heating rate of 10°C / min, and kept for 120 min. The pre-sintered powder is then ground and sintered again at 800°C for 120 min. The non-phase-change dual-phase high-entropy oxide negative electrode material is obtained after the furnace is cooled to room temperature.

[0075] The micro-morphology diagram of the non-phase-change dual-phase high-entropy oxide negative electrode material prepared in this example is shown in Figure 6 From Figure 6 it can be seen that the average particle size of the non-phase-change dual-phase high-entropy oxide negative electrode material prepared in this example is 300 nm.

[0076] Example 3

[0077] A preparation method of a non-phase-change dual-phase high-entropy oxide negative electrode material, comprising the following steps:

[0078] (1) Dissolve zinc acetate, manganese acetate, iron acetate, chromium chloride, ammonium metavanadate, and anhydrous citric acid in a molar ratio of 1:1:1:1:1:2 in an appropriate amount of deionized water and ethanol (water:ethanol=2:1) mixed solution, and magnetically stir at 100°C for 120 min to form a uniform and stable sol. The prepared sol is placed in a drying oven at 180°C to obtain a brown precursor gel. The dried gel is ground to obtain a precursor powder.

[0079] (2) The precursor powder is pre-sintered at 500°C with a heating rate of 5°C / min, and kept for 120 min. The pre-sintered powder is then ground and sintered again at 800°C for 120 min. The non-phase-change dual-phase high-entropy oxide negative electrode material is obtained after the furnace is cooled to room temperature.

[0080] The micro-morphology diagram of the non-phase-change dual-phase high-entropy oxide negative electrode material prepared in this example is shown in Figure 7 FromFigure 6 It can be seen that the non-phase-change two-phase high-entropy oxide negative electrode material prepared in the embodiment has a micron-level sheet structure, and the maximum width thereof can reach about 50 um.

[0081] Finally, it should be noted that: the above specific embodiments are only used to explain the purpose, technical solutions and beneficial effects of the present application in detail, and it should be understood that the above description is only a specific embodiment of the present application and does not limit the protection scope of the present application; although the present application has been described in detail with reference to the foregoing specific embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement, improvement, etc. to part or all of the technical features; and these modifications, equivalent replacement, improvement do not make the essence of the corresponding technical solution deviate from the scope of the technical solutions of the embodiments of the present application, and they should be covered in the scope of the claims and description of the present application.

Claims

1. A phase-change-free dual-phase high-entropy oxide negative electrode material, characterized in that: The high entropy oxide negative electrode material is an oxide containing five metal elements, wherein the five metal elements are selected from any four of magnesium, manganese, cobalt, chromium, zinc, iron and vanadium, and the molar ratio between the five metal elements is (1-3): (1-3): (1-3): (1-3): (1-3); The high entropy oxide negative electrode material contains both a tetragonal system with three-dimensional pores and a spinel phase, and the spinel phase accounts for 65-75% of the physical phase.

2. The non-phase-change dual-phase high-entropy oxide negative electrode material according to claim 1, characterized in that: The high entropy oxide negative electrode material is an oxide containing five metal elements: magnesium, cobalt, chromium, manganese and vanadium, and the molar ratio of magnesium, manganese, cobalt, chromium and vanadium is (1-3): (1-3): (1-3): (1-3): (1-3).

3. The non-phase-change dual-phase high-entropy oxide negative electrode material according to claim 1, characterized in that: The high entropy oxide negative electrode material is an oxide containing five metal elements: zinc, iron, chromium, manganese and vanadium, and the molar ratio of zinc, iron, chromium, manganese and vanadium is (1-2): (1-3): (1-3): (1-3): (1-3).

4. The non-phase-change dual-phase high-entropy oxide negative electrode material according to claim 1, characterized in that: The particle size of the high entropy oxide negative electrode material is in the range of 0.2-1 μm.

5. The method for preparing a non-phase-change dual-phase high-entropy oxide negative electrode material according to claim 1, wherein: The following steps are involved: Weigh a metal salt and anhydrous citric acid in a molar ratio, dissolve them in deionized water or a mixture of deionized water and ethanol, and stir to form a uniform and stable sol or a reaction to form a precipitate; wherein the metal salt is a mixture of metal salts of any four elements selected from magnesium, manganese, cobalt, chromium, zinc, and iron, and a metal salt of vanadium; Drying and grinding the sol or precipitate to obtain precursor powder; The precursor powder is sintered, kept warm, and then cooled to room temperature in the furnace to obtain a phase-change-free dual-phase high-entropy oxide negative electrode material.

6. The method for preparing a phase-change-free dual-phase high-entropy oxide negative electrode material according to claim 5, characterized in that: The molar ratio of the metal salt to anhydrous citric acid is 5:(1-4).

7. The method for preparing a non-phase-change dual-phase high-entropy oxide negative electrode material according to claim 5, characterized in that: The drying temperature of the sol or precipitate is 140-160°C.

8. The method for preparing a non-phase-change dual-phase high-entropy oxide negative electrode material according to claim 5, characterized in that: The sintering and heat preservation of the precursor powder specifically includes: Pre-sintering is performed at 400-500 °C, with a heating rate of 5-10 °C / min, and heat preservation for 100-130 minutes to obtain a pre-sintered powder; The pre-burned powder is ground and sintered again at 750-850°C for 100-130 minutes.

9. Use of the phase-change-free dual-phase high-entropy oxide negative electrode material according to any one of claims 1 to 4 or the phase-change-free dual-phase high-entropy oxide negative electrode material prepared by the method according to any one of claims 5 to 8 in a negative electrode material for a lithium-ion battery.

10. A lithium-ion battery comprising a positive electrode, a negative electrode, an electrolyte and a separator, characterized in that: The negative electrode includes the phase-change-free dual-phase high-entropy oxide negative electrode material according to any one of claims 1 to 4 or the phase-change-free dual-phase high-entropy oxide negative electrode material prepared by the method according to any one of claims 5 to 8.

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