Cathode material, preparation method thereof, cathode sheet, battery and electric device

Abstract

The application discloses a positive electrode material, a preparation method thereof, a positive electrode sheet, a battery and an electric device. a O (2‑b) F b Wherein, X includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W and Ce; 0 < a < 6 and 0 < b < 1. When the positive electrode material is applied to the preparation of a battery, the interface contact reaction between the positive electrode and the electrolyte can be inhibited, the lattice defects caused by the transition metal dissolution in the positive electrode material are reduced, and the high-temperature storage and cycle performance of the battery are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of batteries, and in particular relates to a positive electrode material and a preparation method thereof, a positive electrode sheet, a battery and an electrical device. Background Art

[0002] Lithium-ion batteries and other batteries have the characteristics of high capacity, high voltage, high temperature resistance, and light weight. They have been widely used in electric vehicles, aerospace, energy storage devices, data products and other fields.

[0003] The cycle life performance of a battery is an important indicator for evaluating the performance of secondary batteries and their materials. Among them, the positive electrode material in the battery system is the decisive factor. In the existing positive electrode material system, ternary materials are widely used due to their advantages of high specific energy density and good cycle performance. However, as the number of cycles of charge and discharge increases, especially in extreme use environments, the cycle performance of batteries made of traditional ternary materials will be greatly attenuated. This is mainly due to the following factors: (1) During repeated charge and discharge, especially in extreme environments, the drastic shrinkage of the ternary material unit cell after delithiation leads to the continuous growth of cracks at the grain boundary, which leads to the collapse and decay of the crystal structure; (2) During repeated charge and discharge, the interface reaction between the positive electrode and the electrolyte leads to the dissolution of metal in the surface positive electrode material, causing the lattice reconstruction of the surface positive electrode material to form an inactive rock salt phase and spinel phase, which has an adverse effect on the structure and cycle performance of the positive electrode material. For example, in the charged state, the highly oxidizing Ni in the ternary positive electrode material 4+ Reacting with the electrolyte, it causes the continuous dissolution of transition metal elements at the contact interface between the electrode and the electrolyte, forming inactive rock salt phase NiO or spinel phase material at the interface, which in turn has a negative impact on the cycle performance of the battery.

[0004] Conventional technologies often coat the surface of cathode materials to reduce contact between the cathode material and the electrolyte, thereby improving battery cycle performance. However, the coating layers formed by conventional coating methods have low interfacial bonding strength and poor mechanical properties, resulting in limited improvements in battery cycle performance and failing to meet the increasingly demanding battery performance requirements. Conventional technologies still need improvement. Summary of the Invention

[0005] Based on this, the present invention provides a positive electrode material and a preparation method thereof, a positive electrode sheet, a battery and an electrical device, aiming to improve the cycle performance of the battery.

[0006] The technical solutions of the present invention are as follows.

[0007] In one aspect of the present invention, a positive electrode material is provided, comprising a ternary positive electrode substrate and a coating layer provided on the surface of the ternary positive electrode substrate;

[0008] The components of the coating layer include: LiX a O (2-b) F b , wherein X includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce;

[0009] 0<a<6, 0<b≤1.

[0010] The positive electrode material of the present application includes a ternary positive electrode matrix and a coating layer provided on the surface of the ternary positive electrode matrix. The components of the coating layer have a specific component composition, which can prevent the ternary positive electrode matrix in the positive electrode material from further reacting with the electrolyte to form inactive rock salt phase, spinel phase and other lattice distorted heterogeneous phase substances; at the same time, the F atoms have strong electron-withdrawing properties, so that the transition metal atoms therein will compensate the fluoride for the charge, forming an enhanced "metal-metal" bond energy to improve the interfacial bonding force of the coating layer. When the positive electrode material is used to prepare a battery, it can inhibit the interface contact reaction between the positive electrode and the electrolyte, reduce the lattice defects caused by the dissolution of the transition metal in the positive electrode material, reduce the cycle resistance DCR, and thus improve the high-temperature storage and cycle performance of the battery.

[0011] In some embodiments, the coating layer satisfies at least one of the conditions (a) to (b):

[0012] (a) the coating layer has a thickness of 5 nm to 200 nm;

[0013] (b)1≤a<1.2.

[0014] By regulating the thickness of the coating layer, the coating effect and stability can be further improved, thereby improving the cycle performance of the battery.

[0015] In some embodiments, the coating layer is mainly formed by a composite of metal fluoride, metal oxide and spinel phase compound, and satisfies at least one of the conditions (c) to (g):

[0016] (c) the metal in the metal fluoride includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce;

[0017] (d) The composition of the metal fluoride satisfies: T a1 F, T includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce, 0<a1≤1;

[0018] (e) the metal in the metal oxide includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce;

[0019] (f) The composition of the metal oxide satisfies: L b1 O, L includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce, 0<b1≤2;

[0020] (g) The components of the spinel phase compound satisfy: LiX1 c1 Q1 d1 O4, wherein: 0≤c1≤1, 0≤d1≤1, and c1 and d1 are not 0 at the same time, and Q1 and X1 are independently selected from at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce.

[0021] The above-mentioned spinel phase compound has specific components. Compared with the inactive spinel substance formed during the cycle of the battery, the structure of the spinel phase compound with a specific composition is more stable and maintains a certain electrochemical activity. It can act as a buffer material to absorb the stress accumulation in the crystal lattice of the positive electrode material and inhibit the growth of cracks between grains, thereby improving the mechanical properties of the coating layer; at the same time, the spinel phase and the fluoride formed on the surface form a synergistic complex, in which the F atom has a strong electron-withdrawing property. Therefore, the transition metal atoms in the sublayer spinel phase will compensate the fluoride for the charge, forming an enhanced "metal-metal" bond energy to improve the interfacial bonding strength of the coating layer, thereby further improving the cycle performance of the battery.

[0022] In some embodiments, the coating layer includes a sub-surface layer close to the ternary positive electrode matrix and a surface layer away from the ternary positive electrode matrix, the components of the sub-surface layer mainly include the spinel phase compound, and the components of the surface layer mainly include the metal fluoride.

[0023] The components of the subsurface layer close to the ternary positive electrode matrix mainly include spinel phase compounds, which can act as a buffer layer to absorb the stress accumulation in the lattice of the positive electrode material and inhibit the growth of cracks between grains.

[0024] In some embodiments, the ternary positive electrode matrix satisfies at least one of the conditions (f) to (g),

[0025] (f) The components of the ternary positive electrode matrix meet the following requirements: LiNi x Co y M (1-x-y)O2, wherein 0<x<1, 0<y<1, 0<x+y<1, and M includes at least one of Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, and Ce;

[0026] (g) The particle size of the ternary positive electrode matrix is ​​3 μm to 15 μm.

[0027] Another aspect of the present invention provides a method for preparing a positive electrode material, comprising the following steps:

[0028] An etchant is prepared by mixing a fluorine-containing compound, an oxide, an acidic compound, and a solvent;

[0029] Mixing the etchant with the ternary cathode substrate and pre-etching to obtain a pre-etched mixed material;

[0030] The pre-etched mixed material is sintered to perform an etching reaction to prepare the positive electrode material.

[0031] In the above preparation method, an etchant is first prepared, and the etchant contains a fluorine compound, an oxide, an acidic compound and a solvent. The etchant is then mixed with the ternary positive electrode substrate for pre-etching, so that the components are evenly mixed and a weak reaction occurs at the same time to form a pre-etched mixed material, and then the sintering process is continued to complete the etching reaction. The acidic etchant is used to induce the material on the surface of the alkaline ternary positive electrode substrate to react in situ. Among them, the active metal elements such as transition metal elements on the surface of the ternary positive electrode substrate react with the fluorine-containing compound at high temperature to form metal fluorides and oxides in situ. The acidic compound and solvent in the etchant can promote the reaction activity of the fluoride and the substrate, while the oxide plays two roles: 1) It can capture the excess HF generated by the etching reaction and further repair the substrate interface; 2) It can act as a buffer to better control the acidity of the etchant and promote the uniformity of the etching reaction. At the same time, after the surface of the ternary positive electrode matrix consumes some active metal elements such as transition metal elements, it is easy to form a spinel phase compound with a more stable structure and electrochemical activity, which can act as a buffer layer to absorb stress accumulation in the lattice and inhibit the growth of cracks between grains. More importantly, the spinel phase and metal fluoride induced in situ on the surface compensate for the charge through the strong electron-withdrawing property of F atoms, forming an enhanced "metal-metal" bond energy, and compositely forming a coating layer with a specific component composition, which can prevent the ternary positive electrode matrix in the positive electrode material from further reacting with the electrolyte to form inactive rock salt phase, spinel phase and other lattice-distorted impurities. The prepared positive electrode material can inhibit the interface contact reaction between the positive electrode and the electrolyte, reduce the lattice defects caused by the dissolution of transition metals in the positive electrode material, and reduce the cycle resistance DCR, thereby improving the high-temperature storage and cycle performance of the battery.

[0032] Compared with traditional liquid-phase immersion coating, the above preparation method uses an etchant to induce the material on the surface of the ternary positive electrode matrix to react with acidic fluorine compounds and perform in-situ coating. The formed coating layer has a high interfacial bonding force with the ternary positive electrode matrix and better mechanical properties, which can further improve the high-temperature storage and cycle performance of the battery.

[0033] In some embodiments, the fluorine-containing compound includes one or more of hydrofluoric acid, ammonium fluoride, nickel fluoride, cobalt fluoride, manganese fluoride, lithium fluoride, zirconium fluoride, yttrium fluoride, aluminum fluoride, titanium fluoride, tungsten fluoride, boron fluoride, strontium fluoride, lanthanum fluoride, and magnesium fluoride; and the solvent includes one or more of deionized water, methanol, ethanol, acetone, and ethylene glycol.

[0034] In some embodiments, the oxide includes one or more of aluminum oxide, titanium oxide, magnesium oxide, zirconium oxide, tungsten oxide, strontium oxide, yttrium oxide, boron oxide, lanthanum oxide, cerium oxide, and germanium oxide;

[0035] In some embodiments, the acidic compound includes one or more of boric acid, acetic acid, phosphoric acid, hydrofluoric acid, oxalic acid, oxalic acid, ammonium dihydrogen phosphate, ammonium hydrogen phosphate, hydrogen sulfide, sulfuric acid, ammonium tungstate, etc.;

[0036] The solvent includes one or more of water, methanol, ethanol, acetone, and ethylene glycol. In some embodiments, the mass ratio of the ternary positive electrode matrix, the fluorine-containing compound, the oxide, and the acidic compound is 1:(0.005-0.5):(0.001-0.1):(0.01-10).

[0037] In some embodiments, the method for preparing the positive electrode material satisfies at least one of the conditions (j) to (n):

[0038] The preparation method of the material satisfies at least one of the conditions (j) to (n):

[0039] (j)) the pre-etching time is 5 min to 200 min;

[0040] (k) the pre-etching temperature is 10° C. to 40° C.;

[0041] (1) The etching reaction time is 5h to 30h;

[0042] (m) The temperature of the etching reaction is 40°C to 1000°C.

[0043] (n) The etching reaction is carried out in an oxygen-containing atmosphere

[0044] In some embodiments, the process of preparing the etchant includes the following steps:

[0045] The fluorine-containing compound, the metal oxide, the acidic compound and the solvent are mixed, the pH value of the system is regulated to 4-7 by adjusting the type or addition amount of the acidic compound, and the etchant is obtained after drying.

[0046] In another aspect of the present invention, a positive electrode sheet is provided, comprising a current collector and a positive electrode active layer disposed on the surface of the current collector, wherein the components of the positive electrode active layer include the positive electrode material as described above or the positive electrode material prepared by the method for preparing the positive electrode material as described above.

[0047] In another aspect of the present invention, a battery is provided, comprising the positive electrode material as described above, or the positive electrode material prepared by the method for preparing the positive electrode material as described above, or the positive electrode sheet as described above.

[0048] According to another aspect of the present invention, there is provided an electrical device, comprising the battery as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Figure 1 This is a scanning electron microscope (SEM) image of the ternary positive electrode material prepared in Example 1 of the present invention.

[0050] Figure 2 This is the EDS spectrum of the ternary cathode material prepared in Example 1 of the present application;

[0051] Figure 3 This is a transmission microscope (TEM) image of the ternary cathode material prepared in Example 1 of the present application;

[0052] Figure 4 This is a comparison chart of the cycle performance of the batteries prepared in Example 1, Example 2, Comparative Example 1, Comparative Example 2 and Comparative Example 5 of the present application at 45°C. DETAILED DESCRIPTION

[0053] To facilitate understanding of the present invention, the present invention will be described more fully below, along with preferred embodiments thereof. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present invention.

[0054] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this invention pertains. The terms used herein in the specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0055] The terms "preferably," "more preferably," and the like, used herein refer to embodiments of the present invention that may provide certain benefits under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the present invention.

[0056] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between such minimum and maximum values. Further, when a range refers to an integer, every integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe a feature or characteristic, the ranges can be combined. In other words, unless otherwise indicated, all ranges disclosed herein are understood to include any and all subranges subsumed therein.

[0057] In traditional technology, the surface of the positive electrode material is often coated to reduce the contact probability between the positive electrode material and the electrolyte, thereby improving the cycle performance of the battery. Liquid phase impregnation coating or direct solid phase sintering coating is often used, and the material of the coating layer is often gold oxide.

[0058] However, the oxide coating is easily corroded by the HF by-product in the electrolyte to form a new heterogeneous phase interface, which cannot improve the long-cycle performance. In addition, when liquid-phase impregnation coating or direct solid-phase sintering coating is used, there is only a simple physical force between the interface between the formed coating layer and the positive electrode substrate, resulting in low interfacial bonding force and poor mechanical strength, and limited improvement in the battery's cycle performance.

[0059] The technical staff of the present invention obtained the technical solution of the present invention after a lot of creative experimental exploration

[0060] One embodiment of the present invention provides a positive electrode material, comprising a ternary positive electrode substrate and a coating layer provided on the surface of the ternary positive electrode substrate;

[0061] The components of the coating layer include: LiX a O (2-b) Q b , wherein X includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce;

[0062] 0<a<6, 0<b≤1.

[0063] The positive electrode material of the present application includes a ternary positive electrode matrix and a coating layer provided on the surface of the ternary positive electrode matrix. The components of the coating layer have a specific component composition, which can prevent the ternary positive electrode matrix in the positive electrode material from further reacting with the electrolyte to form inactive rock salt phase, spinel phase and other lattice distorted heterogeneous phase substances; at the same time, the F atoms have strong electron-withdrawing properties, so that the transition metal atoms therein will compensate the fluoride for the charge, forming an enhanced "metal-metal" bond energy to improve the interfacial bonding force of the coating layer. When the positive electrode material is used to prepare a battery, it can inhibit the interface contact reaction between the positive electrode and the electrolyte, reduce the lattice defects caused by the dissolution of the transition metal in the positive electrode material, reduce the cycle resistance DCR, and thus improve the high-temperature storage and cycle performance of the battery.

[0064] In some embodiments, the coating layer has a thickness of 5 nm to 200 nm.

[0065] By regulating the thickness of the coating layer, the coating effect and stability can be further improved, thereby improving the cycle performance of the battery.

[0066] If the coating layer is too thin, it may lead to insufficient doping, poor coating effect, and inability to effectively suppress the generation of grain boundary cracks in the positive electrode material; if the coating layer is too thick, it may cause instability in the phase interface of the positive electrode material or further form new impurity phases, which is not conducive to the optimal electrochemical performance of the positive electrode material.

[0067] Optionally, the thickness of the coating layer is 5nm to 50nm

[0068] It should be noted that "5nm-200nm" refers to a numerical range of 5nm-200nm, which is considered continuous and includes the minimum and maximum values ​​in the range, as well as every value between the minimum and maximum values. Examples include, but are not limited to, 5nm, 10nm, 30nm, 50nm, 80nm, 120nm, 140nm, 160nm, 180nm, or 200nm.

[0069] In some embodiments, the coating layer is mainly formed by a composite of metal fluoride, metal oxide and spinel phase compound, and satisfies at least one of the conditions (c) to (g):

[0070] In some embodiments, the metal in the metal fluoride includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce;

[0071] In some embodiments, the composition of the metal fluoride satisfies: a1F, T includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, Ce, 0

[0072] In some embodiments, the metal in the metal oxide includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, Ce.

[0073] In some embodiments, the components of the metal oxide satisfy: L b1 O, L includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, Ce, 0

[0074] In some embodiments, the components of the spinel phase compound satisfy: LiX1 c1 Q1 d1 O4, wherein: 0≤c1≤1, 0≤d1≤1, and c1and d1are not 0 at the same time, Q1and X1are independently selected from at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, Ce.

[0075] The spinel phase compound described above has a specific composition. Compared with the inactive spinel substance formed in the battery during the cycle process, the structure of the spinel phase compound with the specific composition is more stable, maintains a certain electrochemical activity, can absorb the stress accumulation in the lattice of the positive electrode material as a buffer material, and inhibits the growth of the cracks between the grains, thereby improving the mechanical properties of the coating layer. At the same time, the spinel phase and the fluoride formed on the surface exist in a synergistic compound. The F atom has strong electron-withdrawing properties, and thus the transition metal atoms in the sub-layer spinel phase will charge compensate the fluoride, form an enhanced “metal-metal” bond energy, improve the interface bonding force of the coating layer, and further improve the cycle performance of the battery.

[0076] In some embodiments, 1≤a<1.2.

[0077] In some embodiments, the coating layer includes a sub-surface layer close to the ternary positive electrode matrix and a surface layer away from the ternary positive electrode matrix. The components of the sub-surface layer mainly include the spinel phase compound, and the components of the surface layer mainly include the metal fluoride.

[0078] The components of the sub-surface layer close to the ternary positive electrode matrix mainly include the spinel phase compound, which can absorb the stress accumulation in the lattice of the positive electrode material as a buffer layer and inhibit the growth of the cracks between the grains.

[0079] It can be understood that the above-mentioned "far away from the ternary positive electrode matrix" and "close to the ternary positive electrode matrix" are relative.

[0080] In some embodiments, the components of the ternary positive electrode matrix satisfy: LiNi x Co y M (1-x-y) O2, wherein 0

[0081] It can be understood that the ternary positive electrode matrix in the present application can be various ternary positive electrode materials commonly used in the art, for example, can be LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (also referred to as NCM333 for short), LiNi 0.5 Co 0.2 Mn 0.3 O2 (also referred to as NCM523 for short), LiNi 0.5 Co 0.25 Mn 0.25 O2 (also referred to as NCM211 for short), LiNi 0.6 Co 0.2 Mn 0.2 O2 (also referred to as NCM622 for short), LiNi 0.8 Co 0.1 Mn 0.1 O2 (also referred to as NCM811 for short), lithium nickel cobalt aluminum oxide (such as LiNi 0.85 Co 0.15 Al 0.05 O2) at least one.

[0082] In some embodiments, the particle size of the ternary positive electrode matrix is 3-15 μm.

[0083] In the present application, the particle size of the above-mentioned ternary positive electrode material precursor can be any value or a range composed of any two values selected from 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 15 μm or 15 μm. An embodiment of the present application provides a preparation method of the above-mentioned positive electrode material, comprising the following steps S10-S30.

[0084] Step S10, using a mixture of fluorine-containing compounds, oxides, acidic compounds and solvents to prepare an etchant.

[0085] Step S20, mixing the etchant with the ternary positive electrode matrix to pre-etch, to obtain a pre-etching mixed material.

[0086] Step S30, the pre-etching mixed material is treated by sintering to carry out etching reaction to prepare the positive electrode material.

[0087] In the above preparation method, the etchant is prepared first, which contains fluorine compounds, oxides, acidic compounds and solvents, and then the etchant is mixed with the ternary positive electrode matrix to carry out pre-etching, so that the components are uniformly mixed and a weak reaction occurs at the same time to form a pre-etching mixed material, and the sintering treatment is continued to complete the etching reaction. The material on the surface of the alkaline ternary positive electrode matrix is induced to react in situ by the acidic etchant. Among them, the active metal elements such as transition metal elements on the surface of the ternary positive electrode matrix react with fluorine-containing compounds in situ at high temperature to form metal fluorides and oxides. The acidic compounds and solvents in the etchant can promote the reactivity of fluorides and the matrix, while the oxides play two roles: 1) can capture excess HF generated by etching reaction, further repairing the matrix interface; 2) can act as a buffer to better control the acidity of the etchant and promote the uniformity of the etching reaction. At the same time, after the ternary positive electrode matrix surface consumes part of the active metal elements such as transition metal elements, it is easy to form spinel phase compounds with more stable structure and electrochemical activity, which can act as a buffer layer to absorb stress accumulation in the lattice and inhibit the growth of cracks between the grains. More importantly, the spinel phase and metal fluoride formed in situ on the surface through the strong electron-withdrawing property of F atoms charge compensation, form enhanced "metal-metal" bond energy, and composite form a specific component composition coating layer, which can prevent the ternary positive electrode matrix in the positive electrode material from further reacting with the electrolyte to form inactive rock salt phase, spinel phase and other lattice distorted heterogeneous materials. The prepared positive electrode material can inhibit the interface contact reaction between the positive electrode and the electrolyte, reduce the lattice defects caused by the dissolution of transition metals in the positive electrode material, and reduce the cycle resistance DCR, thereby improving the high-temperature storage and cycle performance of the battery.

[0088] Compared with the traditional liquid phase immersion coating, in the above preparation method, the material on the surface of the ternary positive electrode matrix is induced to react in situ with acidic fluorine compounds and the like to carry out in-situ coating. The interface bonding force of the coating layer formed is high, and the mechanical properties are better, which can further improve the high-temperature storage and cycle performance of the battery.

[0089] In some embodiments, the fluorine compounds and / or oxides contain at least one element of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, Ce.

[0090] In some implementations, the fluorine-containing compound includes one or more of hydrofluoric acid, ammonium fluoride, nickel fluoride, cobalt fluoride, manganese fluoride, lithium fluoride, zirconium fluoride, yttrium fluoride, aluminum fluoride, titanium fluoride, tungsten fluoride, boron fluoride, strontium fluoride, lanthanum fluoride, and magnesium fluoride.

[0091] In some embodiments, the oxide includes one or more of aluminum oxide, titanium oxide, magnesium oxide, zirconium oxide, tungsten oxide, strontium oxide, yttrium oxide, boron oxide, lanthanum oxide, cerium oxide, and germanium oxide.

[0092] In some embodiments, the acidic compound includes one or more of boric acid, acetic acid, phosphoric acid, hydrofluoric acid, oxalic acid, oxalic acid, ammonium dihydrogen phosphate, ammonium hydrogen phosphate, hydrogen sulfide, sulfuric acid, and ammonium tungstate.

[0093] In some embodiments, the solvent includes one or more of water, methanol, ethanol, acetone, and ethylene glycol.

[0094] The water can be deionized water or purified water.

[0095] In some embodiments, the mass ratio of the ternary positive electrode matrix, the fluorine-containing compound, and the oxide is 1:(0.005-0.5):(0.001-0.1).

[0096] The thickness and uniformity of the formed coating layer can be controlled by adjusting the mass ratio of the ternary positive electrode matrix and the fluorine-containing compound.

[0097] Optionally, the mass ratio of the ternary positive electrode matrix to the fluorine-containing compound is 1:(0.005-0.5).

[0098] Optionally, the mass ratio of the ternary positive electrode matrix to the fluorine-containing compound is 1:(0.05-0.5).

[0099] Optionally, the mass ratio of the above-mentioned ternary positive electrode matrix to the fluorine-containing compound is 1:(0.05-0.4).

[0100] Optionally, the mass ratio of the ternary positive electrode matrix to the fluorine-containing compound is 1:(0.05-0.2).

[0101] Optionally, the mass ratio of the ternary positive electrode matrix to the oxide is 1:(0.001-0.1).

[0102] Optionally, the mass ratio of the ternary positive electrode matrix to the oxide is 1:(0.01-0.1).

[0103] Optionally, the mass ratio of the ternary positive electrode matrix to the oxide is 1:(0.01-0.05).

[0104] Optionally, the mass ratio of the ternary positive electrode matrix to the oxide is 1:(0.01-0.01).

[0105] In some embodiments, the mass ratio of the solvent to the ternary positive electrode matrix is ​​(0.0001-0.01):1.

[0106] In some embodiments, in step S20 , the pre-etching temperature is 10° C. to 40° C., and the pre-etching time is 5 min to 200 min.

[0107] The pre-etching process conditions are adjusted to further promote uniform mixing of the components.

[0108] In some embodiments, in step S20 , after the pre-etching process, the process further includes drying the positive electrode material.

[0109] This application has no particular limitation on the drying method.

[0110] Specifically, in the present application, the cathode material was dried in a rotary evaporator at 80° C. for 5 h.

[0111] In some embodiments, in step S10, the process of preparing the etchant includes the following steps:

[0112] The fluorine-containing compound, metal oxide, acidic compound and solvent are mixed, the pH value of the system is regulated to 4-7 by adjusting the type or addition amount of the acidic compound, and the etchant is obtained after drying.

[0113] In some embodiments, the acidic compound includes one or more of boric acid, acetic acid, phosphoric acid, hydrofluoric acid, oxalic acid, oxalic acid, ammonium dihydrogen phosphate, ammonium hydrogen phosphate, hydrogen sulfide, sulfuric acid, and the like.

[0114] In some embodiments, in step S30 , the etching reaction temperature is 40° C. to 1000° C., and the etching time is 5 h to 30 h.

[0115] Optionally, in step S30 , the temperature of the etching reaction is 200° C. to 800° C.

[0116] Specifically, the temperature of the sintering treatment may be 40°C, 50°C, 80°C, 90°C, 100°C, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C, 800°C, 900°C, 1000°C, etc.

[0117] Specifically, the sintering time may be 5 h, 10 h, 15 h, 20 h, 25 h or 30 h.

[0118] In some embodiments, in step S30 , the etching process is performed in an oxygen-containing atmosphere.

[0119] The oxygen-containing atmosphere may be air or oxygen.

[0120] The preparation method has simple process and is easy to carry out large-scale production.

[0121] In the present application, the above-mentioned ternary positive electrode matrix can be prepared according to conventional methods well known to those skilled in the art. For example, the above-mentioned ternary positive electrode matrix can be prepared according to the following method:

[0122] Nickel salt, cobalt salt and M-containing salt are dissolved in deionized water and mixed evenly to form a salt solution. Under nitrogen atmosphere protection and stirring, alkali solution is introduced into the salt solution by a peristaltic pump for precipitation. The pH of the bottom solution is controlled at 10.0-12.0 by ammonia water. After precipitation, the solution is washed with deionized water to obtain a ternary hydroxide precursor, which is then sintered to obtain a ternary positive electrode matrix. M includes at least one of Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge and Ce.

[0123] The chemical formula of the above ternary hydroxide precursor satisfies: Ni x1 Co y1 M( 1-x1-y1) (OH)2, wherein 0<x1<1, 0<y1<1, 0<x1+y1<1. It can be understood that the addition amounts of the above nickel salt, cobalt salt and M-containing salt satisfy the stoichiometric relationship in the chemical formula of the ternary hydroxide precursor.

[0124] The concentration of the salt solution is 0.1 mol / L to 10 mol / L, the concentration of the alkali solution is 0.1 mol / L to 10 mol / L, the precipitation temperature is 20° C. to 100° C., and the precipitation time is 0.5 h to 30 h.

[0125] Specifically, the concentrations of the salt solution and the alkaline solution can be independently selected from: 0.1 mol / L, 1 mol / L, 2 mol / L, 3 mol / L, 4 mol / L, 6 mol / L, 8 mol / L or 10 mol / L.

[0126] Specifically, the reaction temperature of precipitation can be 20°C, 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 95°C or 100°C; the time can be 0.5h, 1h, 2h, 3h, 5h, 10h, 25h, 20h, 25h, or 30h, etc.

[0127] Other point values ​​within the above numerical range can be selected and will not be described in detail here.

[0128] In some embodiments, the sintering further includes jaw crushing and pulverization, so that the particle size of the ternary positive electrode material obtained after pulverization is 3 μm to 15 μm.

[0129] One embodiment of the present invention further provides a positive electrode sheet, which includes a current collector and a positive electrode active layer arranged on the surface of the current collector. The components of the positive electrode active layer include the positive electrode material as described above or the positive electrode material prepared by the preparation method of the positive electrode material as described above.

[0130] The above-mentioned positive electrode sheet can improve the high-temperature storage and cycle performance of the battery.

[0131] In some embodiments, the components of the positive electrode active layer may further include at least one of a binder and a conductive agent.

[0132] The conductive agent may be any commonly used conductive agent in the art, including but not limited to at least one of graphite, carbon nanotubes, nanofibers, carbon black, and graphene. Specifically, the conductive agent may be selected from at least one of SP, KS-6, acetylene black, branched Ketjen black ECP, SFG-6, vapor-grown carbon fiber VGCF, carbon nanotubes CNTs, graphene, and composite conductive agents thereof.

[0133] The above-mentioned binder can be a binder commonly used in the art, such as polyvinylidene fluoride (PVDF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, hydrogenated nitrile rubber, styrene-butadiene rubber (SBR), polyacrylic acid (PAA), etc.

[0134] The above-mentioned current collector can adopt a current collector commonly used in the art, such as a metal foil or a composite current collector. For example, as the metal foil, aluminum foil can be used, which will not be described in detail here.

[0135] One embodiment of the present invention further provides a battery, which comprises the positive electrode material as described above, or the positive electrode material prepared by the method for preparing the positive electrode material as described above, or the positive electrode sheet as described above.

[0136] The battery has excellent high-temperature storage properties and high cycle performance.

[0137] The battery further comprises a negative electrode sheet and a separator, which can be the negative electrode sheet and separator commonly used in the art.

[0138] The battery also includes an electrolyte. Commonly used negative electrode sheets and separators in the art can be used. For example, when the battery is a lithium-ion battery, the electrolyte includes a lithium-ion electrolyte salt and a solvent.

[0139] As an example, the lithium ion electrolyte salt is selected from: one or more of lithium hexafluorophosphate (LiPF6), lithium tetrafluoroborate (LiBF4), lithium perchlorate (LiClO4), lithium hexafluoroarsenate (LiAsF6), lithium bis(fluorosulfonyl)imide (LiFSI), lithium bis(trifluoromethanesulfonyl)imide (LiTFSI), lithium trifluoromethanesulfonate (LiTFS), lithium difluorooxalatoborate (LiDFOB), lithium dioxalatoborate (LiBOB), lithium difluorophosphate (LiPO2F2), lithium difluorobis(oxalatophosphate) (LiDFOP), Li(FSO2)2N, LiCF3SO3 and lithium tetrafluorooxalatophosphate (LiTFOP); the solvent can be selected from one or more of fluoroethylene carbonate (FEC), ethylene carbonate (EC), propylene carbonate (PC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC).

[0140] In some embodiments, the battery is a secondary battery.

[0141] Another embodiment of the present invention provides an electrical device, which includes the battery as described above.

[0142] The electrical device has high cycle performance and long battery life.

[0143] The above-mentioned electrical devices may include, but are not limited to: mobile phones, laptop computers, electric vehicles, ships, satellites, etc.

[0144] The present invention will be described below with reference to specific embodiments, but the present invention is not limited to the following embodiments. It should be understood that the appended claims summarize the scope of the present invention. Under the guidance of the concept of the present invention, those skilled in the art should realize that certain changes made to the various embodiments of the present invention will be covered by the spirit and scope of the claims of the present invention. Specific embodiments

[0146] The parts in the following examples are parts by mass.

[0147] Example 1

[0148] (1) Provide a ternary positive electrode matrix LiNi with a particle size of 3μm to 15μm 0.6 Co 0.1 Mn 0.3 O2 (abbreviated as NCM613).

[0149] (2) 14 g of magnesium fluoride, 14 g of aluminum oxide, 28 g of ammonium tungstate, 42 g of acetic acid and 100 g of deionized water were mixed evenly, and the pH of the system was adjusted to 4.8 with 0.1 mol / L acetic acid. After drying, an etchant was obtained, in which the mass ratio of magnesium fluoride, aluminum oxide, ammonium tungstate and acetic acid was 1:1:2:3.

[0150] (3) The etchant of step (2) and 2.8 kg of the ternary positive electrode substrate were placed in a mixer, the speed was set to 300 rpm / min at 25°C, and mixed for 30 minutes to obtain a pre-etching mixture, wherein the mass ratio of the ternary positive electrode substrate, magnesium fluoride, aluminum oxide, ammonium tungstate, and acetic acid was 1:0.005:0.005:0.01:0.015.

[0151] (4) The pre-etched mixture was sintered in an air atmosphere at 450° C. for 15 h to obtain a positive electrode material.

[0152] The positive electrode material was placed under a scanning electron microscope (SEM) (FEI, quanta200) for observation. Figure 1 As shown, the coating layer can be clearly seen.

[0153] EDS (X-ray energy spectrum analysis) was used to analyze the components of the coating layer of the prepared positive electrode material. The EDS spectrum is shown in FIG. Figure 2 As shown, the components include matrix elements Ni, Co, Mn, and etching elements Mg, Al, F, and W, wherein the mass ratios of Mg, Al, F, and W elements in the ternary positive electrode material are 0.1%, 0.15%, and 0.23%, respectively.

[0154] The thickness of the coating layer of the positive electrode material was tested using a projection scanning microscope TEM (Tecnai G2 F30). The electron microscope image at 10nm is as follows: Figure 3 As shown in (A), the coating thickness is about 18nm. At the same time, the electron microscope image after magnification at 5nm is as follows Figure 3 As shown in (B), the thickness of the spinel phase compound in the lithium-poor area is 10 nm, and its main components are LiM2O4 phase or M3O4 phase (M is mainly Mn element, and some Ni, Co and other elements).

[0155] (5) The positive electrode material prepared above was made into a positive electrode sheet. The test method was as follows: appropriate amounts of the materials prepared in the examples and comparative examples were weighed and assembled into lithium-ion button batteries, wherein the electrode material: conductive carbon black = 90:10 wt%, and the solvent was NMP. The batteries were dried in a vacuum oven at 80°C for 24 h to obtain a battery sheet with an area density of 1.2 mg / cm 2 .

[0156] (6) Testing:

[0157] 1. Test the high temperature storage performance of lithium-ion batteries. The test method is as follows:

[0158] When the battery was fully charged (4.4V), it was disassembled after being stored at 60°C for 30 days and 60 days respectively. The positive electrode was cleaned with DMC, and the active material layer of the positive electrode was scraped off after drying. It was then heated in aqua regia for 30 minutes to dissolve it. The solution was subjected to ICP testing for Ni, Co, and Mn content. The test results are shown in Table 1.

[0159] 2. Test the cycle performance of lithium-ion batteries. The test method is as follows:

[0160] The positive electrode materials prepared in the examples and comparative examples were subjected to a 45°C cycling performance test. The test method was as follows: appropriate amounts of the materials prepared in the examples and comparative examples were weighed and assembled into button-type batteries, wherein the electrode material: conductive carbon black = 90:10 wt %, the solvent was NMP, and the battery electrode sheet surface density was 1.2 mg / cm 2 , at a voltage of 2.8-4.4V and 25°C, after one cycle of charge and discharge at a rate of 0.1C / 0.1C, after one cycle of activation at 0.1C / 1C charge and discharge, the cycle performance test (50 cycles) was carried out at a rate of 1C / 1C at 45°C. The test results are shown in Table 2 below.

[0161] Please see Table 2 for specific results.

[0162] Examples 2 to 6

[0163] Examples 2 to 6 are basically the same as Example 1, except that the etching treatment time or temperature or raw material mass ratio is regulated in step (2) so that the thickness of the coating layer of the obtained positive electrode material is different from that of Example 1.

[0164] The other steps are the same as those in Example 1. Please see Table 1 for specific parameters and results.

[0165] Examples 7 to 10

[0166] Examples 7 to 10 are basically the same as Example 1, except that the types of fluorine-containing compounds and oxides in step (2) are different from those in Example 1.

[0167] The other steps are the same as those in Example 1. Please see Table 1 for specific parameters and results.

[0168] Examples 11 to 13

[0169] Examples 11 to 13 are basically the same as Example 1, except that the type of the acidic compound in step (2) is different from that in Example 1.

[0170] The other steps are the same as those in Example 1. Please see Table 1 for specific parameters and results.

[0171] Comparative Example 1

[0172] (1) Provide a ternary positive electrode matrix (LiNi) with a particle size of 3 μm to 15 μm 0.6 Co 0.1 Mn 0.3 O2, can also be referred to as NCM613)).

[0173] (2) 14 g of magnesium fluoride was mixed with 2.8 kg of the ternary positive electrode matrix and then sintered to perform an etching reaction. The etching reaction conditions were the same as those in Example 1.

[0174] The other steps are the same as those in Example 1. Please see Table 1 for specific parameters and results.

[0175] Comparative Example 2

[0176] (1) Provide a ternary positive electrode matrix (LiNi) with a particle size of 3 μm to 15 μm 0.6 Co 0.1 Mn 0.3 O2, can also be referred to as NCM613)).

[0177] (2) After mixing 14 g of aluminum oxide with 2.8 kg of the ternary positive electrode substrate, the mixture was sintered to perform an etching reaction. The etching reaction conditions were the same as those in Example 1.

[0178] The other steps are the same as those in Example 1. Please see Table 1 for specific parameters and results.

[0179] Comparative Example 3

[0180] (1) Provide a ternary positive electrode matrix (LiNi 0.6 Co 0.1 Mn 0.3 O2, can also be referred to as NCM613)).

[0181] (2) 14 g of magnesium fluoride and 14 g of aluminum oxide were mixed with deionized water and dried, and then mixed with 2.8 kg of the ternary positive electrode matrix, and then sintered to perform an etching reaction. The etching reaction conditions were the same as those in Example 1.

[0182] The other steps are the same as those in Example 1. Please see Table 1 for specific parameters and results.

[0183] Comparative Example 4

[0184] (1) Provide a ternary positive electrode matrix (LiNi 0.6 Co 0.1 Mn 0.3 O2, can also be referred to as NCM613)).

[0185] (2) 2.5 kg of ternary positive electrode matrix and 14 g of spinel phase compound LiNi 0.5 Mn1.5 O4, mixed and sintered, the sintering conditions are the same as those in Example 1.

[0186] The other steps are the same as those in Example 1. Please see Table 1 for specific parameters and results.

[0187] Comparative Example 5

[0188] The ternary positive electrode substrate was not subjected to coating treatment. The other steps were the same as in Example 1. The specific parameters and results are shown in Table 1.

[0189] The parameters and specific results of each embodiment and comparative example are shown in Table 1. The mass ratio of the ternary positive electrode matrix and the fluorine-containing compound is recorded as: m1:m2, where M is mainly Mn and some Ni and Co elements.

[0190] Table 1

[0191]

[0192]

[0193]

[0194] “ / ” indicates that the process step or structure does not exist.

[0195] The performance test results of each embodiment and comparative example are shown in Table 2.

[0196] Table 2

[0197]

[0198] The comparison of the cycle performance of the batteries prepared in Example 1, Example 2, Comparative Example 1, Comparative Example 2 and Comparative Example 5 at 45°C is shown in the figure below: Figure 4 shown.

[0199] From the analysis of the results in Tables 1 and 2, it can be seen that when the positive electrode material of the present application is used to prepare a battery, it can inhibit the interface contact reaction between the positive electrode and the electrolyte, reduce the lattice defects caused by the dissolution of transition metals in the positive electrode material, and thus improve the high-temperature storage and cycle performance of the battery.

[0200] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0201] The above embodiments only express several implementation manners of the present application, and the description is relatively specific and detailed, but should not be understood as a limitation on the patent scope of the present application. It should be noted that, for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A positive electrode material, characterized in that The positive electrode material includes a ternary positive electrode substrate and a coating layer provided on the surface of the ternary positive electrode substrate; The components of the coating layer include: LiX a O (2-b) F b , wherein X includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce; 0<a<6, 0<b≤1; The coating layer is mainly composed of a metal fluoride, a metal oxide and a spinel phase compound. The metal in the metal fluoride includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce. The metal in the metal oxide includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce. The components of the spinel phase compound meet the following requirements: LiX1 c1 Q1 d1 O4, wherein: 0≤c1≤1, 0≤d1≤1, and c1 and d1 are not 0 at the same time, Q1 and X1 are independently selected from at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce; The coating layer includes a subsurface layer close to the ternary positive electrode matrix and a surface layer away from the ternary positive electrode matrix. The components of the subsurface layer mainly include the spinel phase compound, and the components of the surface layer mainly include the metal fluoride.

2. The positive electrode material according to claim 1, wherein The coating layer satisfies at least one of the conditions (a) to (b): (a) the coating layer has a thickness of 5 nm to 200 nm; (b)1≤a<1.

2.

3. The positive electrode material according to claim 1, wherein The coating layer satisfies at least one of the conditions (e) to (f): (e) The composition of the metal fluoride satisfies: T a1 F, T includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce, 0<a1≤1; (f) The composition of the metal oxide satisfies: L b1 O, L includes at least one of Ni, Co, Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, W, and Ce, and 0<b1≤2.

4. The positive electrode material according to any one of claims 1 to 3, wherein The ternary positive electrode matrix satisfies at least one of the conditions (h) to (i), (h) The components of the ternary positive electrode matrix meet the following requirements: LiNi x Co y M (1-x-y) O2, wherein 0<x<1, 0<y<1, 0<x+y<1, and M includes at least one of Mn, Al, B, Y, Zr, Sr, La, Ti, Mg, Zn, Fe, Nb, Ge, and Ce; (i) The particle size of the ternary positive electrode matrix is ​​3 μm to 15 μm.

5. The method for preparing the positive electrode material according to any one of claims 1 to 4, wherein: The steps include: The etchant is prepared by mixing a fluorine-containing compound, an oxide, an acidic compound and a solvent; Mixing the etchant with the ternary cathode substrate and pre-etching to obtain a pre-etched mixed material; The pre-etched mixed material is sintered to perform an etching reaction to prepare the positive electrode material.

6. The method for preparing the positive electrode material according to claim 5, wherein: The fluorine-containing compound includes one or more of hydrofluoric acid, ammonium fluoride, nickel fluoride, cobalt fluoride, manganese fluoride, lithium fluoride, zirconium fluoride, yttrium fluoride, aluminum fluoride, titanium fluoride, tungsten fluoride, boron fluoride, strontium fluoride, lanthanum fluoride, and magnesium fluoride; The oxide includes one or more of aluminum oxide, titanium oxide, magnesium oxide, zirconium oxide, tungsten oxide, strontium oxide, yttrium oxide, boron oxide, lanthanum oxide, cerium oxide, and germanium oxide; The acidic compound includes one or more of boric acid, acetic acid, phosphoric acid, hydrofluoric acid, oxalic acid, ammonium dihydrogen phosphate, ammonium hydrogen phosphate, hydrogen sulfide, sulfuric acid, and ammonium tungstate; The solvent includes one or more of water, methanol, ethanol, acetone, and ethylene glycol.

7. The method for preparing a positive electrode material according to any one of claims 5 to 6, wherein: The mass ratio of the ternary positive electrode matrix, the fluorine-containing compound, the oxide and the acidic compound is 1:(0.005~0.5):(0.001~0.1):(0.01~10).

8. The method for preparing a positive electrode material according to any one of claims 5 to 6, wherein: The preparation method of the positive electrode material satisfies at least one of the conditions (j) to (n): (j) the pre-etching time is 5 min to 200 min; (k) the pre-etching temperature is 10° C. to 40° C.; (1) The etching reaction time is 5 h to 30 h; (m) the temperature of the etching reaction is 40° C. to 1000° C.; (n) The etching reaction is carried out in an oxygen-containing atmosphere.

9. The method for preparing a positive electrode material according to any one of claims 5 to 6, wherein: The process of preparing the etchant comprises the following steps: The fluorine-containing compound, the oxide, the acidic compound, and the solvent are mixed, the pH value of the system is regulated to 4-7 by adjusting the type or addition amount of the acidic compound, and the etchant is obtained after drying.

10. A positive electrode sheet, characterized in that: The positive electrode sheet includes a current collector and a positive electrode active layer provided on the surface of the current collector, and the components of the positive electrode active layer include the positive electrode material according to any one of claims 1 to 4 or the positive electrode material prepared by the preparation method of the positive electrode material according to any one of claims 5 to 9.

11. A battery, characterized in that: The battery comprises the positive electrode material according to any one of claims 1 to 3, or the positive electrode material prepared by the method for preparing the positive electrode material according to any one of claims 5 to 9, or the positive electrode sheet according to claim 10.

12. An electrical device, characterized in that: The electric device comprises the battery as claimed in claim 11.

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