Oxide precursors, methods for producing the same, and applications

Abstract

An oxide precursor, a method for producing the same, and its applications are provided. The general chemical formula of the oxide precursor is Ni x Co y Mn z Al d M e O n And here, 0

Description

Technical Field

[0001] This application relates to the field of lithium-ion battery technology, and particularly to oxide precursors, methods for manufacturing the same, and applications thereof.

Background Art

[0002] Currently, layered lithium-ion cathode materials using doping modification have better performance and are widely noticed. Conventional doping ions include Mg 2+ , Fe 2+ , Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Ti 4+ and so on. However, elements such as Ba 2+ (ionic radius 0.135 nm), Y 3+ (ionic radius 0.09 nm), Ag + (ionic radius 0.115 nm), Sr 2+ (ionic radius 0.118 nm), Cs + (ionic radius 0.167 nm), K + (ionic radius 0.138 nm), Na + (ionic radius 0.102 nm), In 3+ (ionic radius 0.08 nm) have large ionic radii and are difficult to be uniformly doped into the crystal phase. Furthermore, since the precursor itself used in the manufacture of the doped modified cathode material is agglomerated particles having a certain particle size (8 μm - 15 μm), the diffusion path of the doping element becomes long, and a phenomenon where the concentration of the surface layer doping element is higher than the concentration of the internal doping element or a local enrichment phenomenon is likely to occur, which is disadvantageous for the doping element to fully exert its modification effect in the cathode material. As a result, it affects the cycle performance of the lithium-ion battery.

Summary of the Invention

Problems to be Solved by the Invention

[0003] In view of this, in order to solve the above problems, it is necessary to provide an oxide precursor, a method for manufacturing the same, and an application. The oxide precursor has a doped element M with a large ionic radius that is uniformly distributed, which is advantageous for improving the structural stability of the cathode material and enabling a lithium-ion battery to have excellent discharge capacity and cycle performance.

Means for Solving the Problems

[0004] Provide an oxide precursor, the chemical general formula of the oxide precursor is Ni x Co y Mn z Al d M e O n where 0 < x ≦ 0.96, 0 ≦ y ≦ 0.96, 0 ≦ z ≦ 0.96, 0 ≦ d ≦ 0.15, 0 < e ≦ 0.015, 0.6 ≦ n ≦ 1.6, x + y + z + d = 1, and y, z, d are not simultaneously 0, and the ionic radius of the metal element M ≧ 0.08 nm. The degree of uniform distribution of the metal element M in the oxide precursor is 98.5% or more.

[0005] In one embodiment, D of the oxide precursor 50 ≦ 2 μm.

[0006] In one embodiment, the crystal lattice parameters of nickel oxide in the oxide precursor satisfy 2.9553 Å ≦ a ≦ 2.9702 Å, 2.9553 Å ≦ b ≦ 2.9702 Å, 7.2285 Å ≦ c ≦ 7.2425 Å.

[0007] In one embodiment, in the X-ray diffraction spectrum, the ratio of the diffraction peak intensity of the (012) crystal plane of the oxide precursor to the diffraction peak intensity of the (101) crystal plane is 1:1 - 2:1.

[0008] In one embodiment, in the X-ray diffraction spectrum, compared with the diffraction peak of the (012) crystal plane of standard nickel oxide, the diffraction peak of the (012) crystal plane of the oxide precursor shifts to a smaller angle, and the shift amount is 3° or less.

[0009] In one embodiment, the metal element M is Ca, Sn, Cd, At least one of the following is selected: Ba, Y, Ag, Sr, Cs, K, Na, In, Ce, Tl, Bi, Sc, Yb, Tm, Er, Te, or Pd.

[0010] In one embodiment, the oxide precursor is (1) Bulk density of the oxide precursor ≥ 0.4 g / cm³ 3 The condition is, (2) D of the oxide precursor 10 The condition is ≤0.5μm, (3) D of the oxide precursor 90 The condition is ≤10μm, (4) The particle size distribution span value of the oxide precursor is ≤ 5, and the particle size distribution span value is (D 90 -D 10 ) / D 50 It satisfies at least one of the following conditions.

[0011] In one example, the overall uniformity of the distribution of the oxide precursors of the elements Ni, Co, Mn, and Al is 98% or higher.

[0012] The oxide precursor according to this application not only contains a doping element M with a large ionic radius in a specific blending ratio, but also exhibits excellent doping uniformity. When used in the manufacture of a positive electrode material, the main phase of the positive electrode material is all affected by the doping element M, and the crystal structure can be uniformly stabilized. At the same time, the uniformly distributed doping element M equalizes the stress distribution, avoiding cracking of crystal grains due to localized stress concentration. As a result, the cycle capacity retention rate is improved, and lithium-ion batteries can be made to have excellent discharge capacity and cycle performance.

[0013] The above-mentioned method for producing an oxide precursor, Ni x Co y Mn z Al d M e O n, based on the conditions that \(0 \lt x \leq 0.96\), \(0 \leq y \leq 0.96\), \(0 \leq z \leq 0.96\), \(0 \leq d \leq 0.15\), \(0 \lt e \leq 0.015\), \(0.6 \leq n \leq 1.6\), \(x + y+ z + d = 1\), and \(y\), \(z\), \(d\) are not simultaneously \(0\), a mixed metal salt solution is prepared and subjected to a coprecipitation reaction with a precipitant solution to obtain 50 a hydroxide with \(D = 0.2\ \mu m - 1\ \mu m\), and a step of sintering the hydroxide to obtain the oxide precursor, which includes.

[0014] In one embodiment, the coprecipitation reaction is (1) the condition that the molar ratio of metal ions in the mixed metal salt solution to hydroxide ions in the precipitant solution is \(1:1 - 1:1.15\), (2) the condition that the total concentration of the mixed metal salts in the mixed metal salt solution is \(0.5\ mol / L - 3\ mol / L\), (3) the condition that the concentration of the precipitant in the precipitant solution is \(0.5\ mol / L - 6\ mol / L\), (4) the condition that the precipitant in the precipitant solution is selected from at least one of potassium hydroxide, sodium hydroxide or lithium hydroxide, (5) satisfying at least one of the conditions that the temperature of the coprecipitation reaction is \(25^{\circ}C - 45^{\circ}C\) and the time is \(3\ h - 10\ h\).

[0015] In one embodiment, the step of sintering the hydroxide precipitate is (1) the condition that the volume of the hydroxide is \(5\% - 35\%\) of the volume of the intermediate, Yusora (2) the condition that the sintering is carried out in an oxygen-containing gas, the oxygen content in the oxygen-containing gas is \(21\%\) or more, and the flow rate of the oxygen-containing gas is \(1\ L / min - 30\ L / min\), (3) satisfying at least one of the conditions that the temperature of the sintering is \(350^{\circ}C - 650^{\circ}C\) and the time is \(1\ h - 6\ h\).

[0016] <00002​​​​In one embodiment, the molar amount of metal element M is 0.01 mol% to 1.5 mol% of the molar amount of other metal elements in the positive electrode material, excluding Li and element M.

[0018] A positive electrode plate comprising the positive electrode material as described above is provided.

[0019] A lithium-ion battery is provided that includes a positive electrode plate as described above.

[0020] As described above, we provide an electrical device equipped with a lithium-ion battery. [Effects of the Invention]

[0021] The manufacturing method described herein eliminates the use of complexing agents used in conventional manufacturing methods, and by adding only a precipitating agent, uniform small-particle hydroxides of doped element M are rapidly generated during the coprecipitation reaction. Subsequently, during the sintering of the hydroxides, doped element M with a large ionic radius and small-particle hydroxides are rapidly formed. Hydroxide precursor The synergistic effect of the short-range diffusion pathways provided allows for uniform diffusion of doped element M, further improving the uniform distribution effect of doped element M. This enables the production of oxide precursors in which doped element M with a large ionic radius is uniformly distributed. This not only solves the problem of difficulty in achieving uniform doping of elements with a large ionic radius using conventional doping methods, but also results in a simple and easy-to-operate manufacturing method with a short usage time and high efficiency. [Brief explanation of the drawing]

[0022] To more clearly describe the embodiments of the present application or the solutions of the prior art, the drawings that may be used in the description of the embodiments or the prior art are briefly described below. Naturally, the drawings described below are some embodiments of the present application, and those skilled in the art will be able to conceive of other drawings based on these without requiring any creative effort. [Figure 1] This is a SEM cross-sectional view of the oxide precursor provided in Example 1 of the present application. [Figure 2] This is an SEM cross-sectional view of the oxide precursor provided in Comparative Example 1 of this application.

Best Mode for Carrying Out the Invention

[0023] To facilitate understanding of the present application, the present application will be described in more detail below. However, it should be understood that the present application can be implemented in many different forms without being limited to the embodiments or examples described in this specification. Rather, these embodiments or examples are provided to more thoroughly and completely understand the disclosed content of the present application.

[0024] The meanings of all technical and scientific terms used in this specification are the same as those commonly understood by those skilled in the technical field of the present application, unless otherwise specifically defined. Book The terms used in the specification of the present application are for the purpose of describing specific embodiments or examples and are not intended to limit the present application. The selection range of the term "and / or" used in this specification includes any one of two or more related listed items, as well as any combination and all combinations of the related listed items. The above-mentioned any combination and all combinations include any two related listed items, any more related listed items, or combinations of all related listed items.

[0025] The present application provides an oxide precursor, and the chemical general formula of the oxide precursor is Ni x Co y Mn z Al d M e O n where 0 < x ≤ 0.96, 0 ≤ y ≤ 0.96, 0 ≤ z ≤ 0.96, 0 ≤ d ≤ 0.15, 0 < e ≤ 0.015, 0.6 ≤ n ≤ 1.6, x + y + z + d = 1, and y, z, d are not simultaneously 0, and the ionic radius of the metal element M ≥ 0.08 nm.

[0026] At least 10 sample regions are selected from the oxide precursor, and the mass of the metal element M in any of the sample regions is calculated as a percentage of the total elemental mass, with a standard deviation of σ1 ≤ 1.5%. The uniformity of the distribution of the metal element M in the oxide precursor is defined as 1-σ1, i.e., the uniformity of the distribution of the metal element M in the oxide precursor is 98.5% or higher.

[0027] Ni, Co, Mn, and Al are the main group elements, and the metallic element M is the doping element. The oxide precursor can be selected from a binary precursor with the main group elements being Ni, Co, or Ni, Mn, or Ni, Al; a ternary precursor with the main group elements being Ni, Co, Mn, or Ni, Co, Al, or Ni, Mn, Al; or a quaternary precursor with the main group elements being Ni, Co, Mn, or Al.

[0028] The oxide precursor according to this application not only contains a doping element M with a large ionic radius in a specific blending ratio, but also exhibits excellent doping uniformity. When used in the manufacture of a positive electrode material, the main phase of the positive electrode material is all affected by the doping element M, and the crystal structure can be uniformly stabilized. At the same time, the uniformly distributed doping element M equalizes the stress distribution, avoiding cracking of crystal grains due to localized stress concentration. As a result, the cycle capacity retention rate is improved, and lithium-ion batteries can be made to have excellent discharge capacity and cycle performance.

[0029] In one embodiment, the oxide precursor D 50 ≤2μm, where D 50 This refers to the particle size at which the percentage of the cumulative particle size distribution of oxide precursor particles reaches 50%, and can be used to represent the average particle size. Because the average particle size of the oxide precursor is small, it can provide a short diffusion pathway for the doped element M, and thus, due to the synergistic effect of the doped element M with a large ionic radius and the oxide precursor with a small particle size, the doped element M Bulk phase of cathode material Further improve the uniformity of the distribution in this context.

[0030] In one embodiment, the oxide precursor satisfies the following crystal lattice parameters of nickel oxide in XRD analysis: 2.9553 Å ≤ a ≤ 2.9702 Å, 2.9553 Å ≤ b ≤ 2.9702 Å, and 7.2285 Å ≤ c ≤ 7.2425 Å. Compared to the nickel oxide crystal lattice parameters of the R-3m space group of the standard PDF card (PDF#44-1159) (a=b=2.9552 Å, c=7.2275 Å), the crystal lattice parameters a, b, and c of the oxide precursor are each independently 0. The increase is 0.001 Å to 0.015 Å, which is advantageous for cooperatively adjusting and controlling the uniformity of the doped sites in the bulk phase of the doped element M in the oxide precursor. This further improves the uniformity of the doped sites in the cathode material of the doped element M, and it is even more preferable that 2.9572 Å ≤ a ≤ 2.9632 Å, 2.9572 Å ≤ b ≤ 2.9632 Å, and 7.2295 Å ≤ c ≤ 7.2355 Å, where a, b, and c each increase independently by 0.002 Å to 0.008 Å.

[0031] In one embodiment, the ratio of the (012) crystal plane diffraction peak intensity to the (101) crystal plane diffraction peak intensity of the oxide precursor in the X-ray diffraction spectrum is 1:1-2:1, i.e., I(012) / I(101) = 1.0-2.0. This imparts an appropriate degree of crystallinity to the oxide precursor, which is advantageous for improving the quality and performance of the cathode material.

[0032] In one embodiment, the X-ray diffraction spectrum shows that the (012) crystal plane diffraction peak of the oxide precursor is shifted to a smaller angle and the amount of shift is 3° or less compared to the (012) crystal plane diffraction peak of standard nickel oxide.

[0033] In one embodiment, the metallic element M includes, but is not limited to, at least one of Ba, Y, Ag, Sr, Cs, K, Na, In, Ce, Tl, Bi, Sc, Yb, Tm, Er, Te, or Pd.

[0034] In one embodiment, the oxide precursor is (1) Bulk density of the oxide precursor ≥ 0.4 g / cm³ 3 The condition is, (2) D of the oxide precursor 10 The condition is ≤0.5μm, (3) D of the oxide precursor 90 The condition is ≤10μm, (4) The particle size distribution span value of the oxide precursor is ≤ 5, and the particle size distribution span value is (D 90 -D 10 ) / D 50 It satisfies at least one of the following conditions.

[0035] By adjusting and controlling the particle size distribution of the oxide precursor, the doped element M becomes more easily diffused by the bulk phase of the cathode material. At the same time, by controlling the distribution so that the oxide precursor has an appropriate bulk density, the oxide precursor has an appropriate volume per unit mass, which is further advantageous for improving the processing performance of the cathode material.

[0036] Here, D 10 This refers to the particle size at which the cumulative particle size distribution percentage of oxide precursor particles reaches 10%, and D 90 This refers to the particle size at which the cumulative particle size distribution percentage of oxide precursor particles reaches 90%.

[0037] In one embodiment, at least 10 sample regions are selected from the oxide precursor, and the total mass of Ni, Co, Mn, and Al elements in any of the sample regions is calculated as a percentage of the total elemental mass, with a standard deviation of σ² ≤ 2%, and the overall uniformity of the distribution of Ni, Co, Mn, and Al elements in the oxide precursor is defined as 1-σ², i.e., the overall uniformity of the distribution of Ni, Co, Mn, and Al elements in the oxide precursor is 98% or higher.

[0038] Conventional precursor doping modification is mainly classified into two methods. One is a method in which, before manufacturing a cathode material by a high-temperature solid-phase method, a dopant element-containing additive is uniformly mixed with a precursor synthesized by a coprecipitation method and a lithium source, and then fired. Since the precursor itself is agglomerated particles having a certain particle size (8 μm - 15 μm), in the reaction stage, the dopant element enters the bulk phase of the cathode material by diffusion, the diffusion path is long, and it is difficult to achieve uniform doping. In addition, since simple mechanical mixing is used, it is difficult to achieve a uniform distribution of the dopant element in the precursor, and it is also difficult to achieve uniform doping. On the other hand, the other is a method in which, in the manufacturing process of the coprecipitation precursor, various condition parameters are adjusted to dope the dopant element into the coprecipitation precursor. Since there are many condition parameters that need to be adjusted and they affect each other, it is difficult to manufacture a consistent doping precursor. In addition, this method requires readjustment to change the dopant element and the process, has low versatility, and the manufacturing difficulty is greatly increased.

[0039] In view of this, the present application provides a method for manufacturing an oxide precursor as described above, and this manufacturing method includes S1 to S2. In S1, Ni x Co y Mn z Al d M e O n , where 0 < x ≤ 0.96, 0 ≤ y ≤ 0.96, 0 ≤ z ≤ 0.96, 0 ≤ d ≤ 0.15, 0 < e ≤ 0.015, 0.6 ≤ n ≤ 1.6, x + y + z + d = 1, and it is specified that y, z, and d are not simultaneously 0, a mixed metal salt solution is prepared, and a coprecipitation reaction is carried out with a precipitant solution to obtain a hydroxide, and the D 50 of the hydroxide is 0.2 μm - 1 μm. In S2, the hydroxide is sintered to obtain the oxide precursor.

[0040] In step S1, without using a complexing agent used in the conventional manufacturing method and by adding only a precipitant, specific small-particle-size hydroxides are rapidly generated during the coprecipitation reaction, which is advantageous for ensuring the uniformity of each element, and in particular, the metal element M can be uniformly doped.

[0041] In one embodiment, the coprecipitation reaction is carried out as follows: (1) Under the condition that the molar ratio of metal ions in the mixed metal salt solution to hydroxide ions in the precipitant solution is 1:1 to 1:1.15, (2) The condition that the total concentration of the mixed metal salts in the mixed metal salt solution is 0.5 mol / L to 3 mol / L, (3) Under the condition that the concentration of the precipitant in the precipitant solution is 0.5 mol / L to 6 mol / L, (4) The condition that the precipitant in the precipitant solution is selected from at least one of potassium hydroxide, sodium hydroxide, or lithium hydroxide, (5) The coprecipitation reaction is performed at least one of the following conditions: the temperature is 25°C-45°C and the duration is 3h-10h.

[0042] Temperature of the coprecipitation reaction in the manufacturing method relating to this application Low The processing time is shorter, the conditions are milder, processing costs can be reduced while ensuring that the hydroxide has a consistent particle size, and the uniformity of each element can be guaranteed.

[0043] In one embodiment, a specific method for the coprecipitation reaction is to introduce the mixed metal salt solution into the reaction apparatus in parallel with the precipitant solution.

[0044] It can be understood that the process after the completion of the coprecipitation reaction may include normal processing steps such as aging, washing, and drying, and this application is not limited thereto.

[0045] In step S2, during the sintering of the hydroxide, doping elements M with a large ionic radius and small particle size are added. hydroxide The synergistic effect of the short-range diffusion pathways provided by allows the doped element M to diffuse uniformly, further enhancing the uniform distribution effect of the doped element M. Thus, an oxide precursor is produced in which the doped element M with a large ionic radius is uniformly distributed.

[0046] In one embodiment, the step of sintering the hydroxide precipitate is: (1) The volume of the hydroxide is when fired YusoraThe condition is that the inter-volume is between 5% and 35%. (2) The sintering is carried out in an oxygen-containing gas, the oxygen content in the oxygen-containing gas is 21% or more, and the flow rate of the oxygen-containing gas is 1 L / min to 30 L / min. (3) The sintering temperature is 350°C-650°C and the duration is 1h-6h, satisfying at least one of these conditions.

[0047] Here, the volume of the hydroxide is when fired Yusora The proportion of the intervening volume represents the packing rate of the reaction material.

[0048] By adjusting and controlling the sintering temperature, time, packing density of the reaction material, reaction gas, and flow rate, it is possible not only to ensure uniform diffusion of the doping element M, but also to impart a certain particle size distribution, bulk density, and crystallinity to the oxide precursor, and to reduce sintering costs, which is advantageous for industrial production.

[0049] The specific steps of the manufacturing method relating to this application include, but are not limited to, intermittent and continuous steps, and this application does not restrict them.

[0050] Therefore, the manufacturing method according to this application not only solves the problem of difficulty in achieving uniform doping of elements with large ionic radii using conventional doping methods, but also has a simple manufacturing method that is easy to operate, requires little time, and is highly efficient.

[0051] The present invention provides a cathode material manufactured from an oxide precursor as described above, wherein at least 10 sample regions are selected from the cathode material, and the mass of metal element M in any of the sample regions is calculated as a percentage of the total elemental mass, with a standard deviation of σ3 ≤ 1.5%, and the uniformity of the distribution of metal element M in the cathode material is defined as 1-σ3, i.e., the uniformity of the distribution of metal element M in the cathode material is 98.5% or higher.

[0052] The positive electrode material according to this invention not only has a uniform and stable crystal structure, but also a uniform stress distribution within the material, making it less susceptible to defects such as crystal grain cracking during charging and discharging. In this way, it helps to improve the cycle capacity retention rate, enabling lithium-ion batteries to have excellent discharge capacity and cycle performance.

[0053] Furthermore, when the metal element M is doped, it may occupy lithium ion sites, transition metal ion sites, or it may occupy both types of sites simultaneously to form a mixed-doped site, and this invention is not limited to these.

[0054] In one embodiment, the molar amount of metal element M is 0.01 mol% to 1.5 mol% of the molar amount of other metal elements in the positive electrode material, excluding Li and element M.

[0055] Furthermore, this application does not impose any restrictions on the manufacturing method of the cathode material, and it is possible to manufacture it using conventional methods. For example, the oxide precursor and lithium source according to this application are thoroughly mixed in a molar ratio of 1:(1-1.5) to obtain a mixture, and then the mixture is calcined at a high temperature of 650°C-1000°C in an oxygen or air atmosphere to obtain the cathode material. In this process, the slight loss of metal element M during the manufacturing process is compensated for, and it is also possible to replenish the mixture with an additive containing metal element M, with a molar ratio of 1:(0.0001-0.05) between the oxide precursor and the additive containing metal element M.

[0056] This application provides a positive electrode plate comprising the positive electrode material as described above.

[0057] Specifically, the positive electrode plate includes a positive electrode current collector and a positive electrode film layer disposed on at least one surface of the positive electrode current collector, and the positive electrode film layer includes the positive electrode material according to the present invention.

[0058] In one embodiment, a metal foil plate or a composite current collector can be used as the positive electrode current collector. For example, aluminum foil can be used as the metal foil plate. The composite current collector includes a polymer material substrate and a metal layer formed on at least one surface of the polymer material substrate. The composite current collector has a metal material on a polymer material substrate. layer It can be formed by forming a metal layer. Selectively, the metal material layer includes, but is not limited to, one or more of aluminum, aluminum alloys, nickel, nickel alloys, titanium, titanium alloys, silver, and silver alloys. Selectively, the polymer material substrate includes, but is not limited to, one or more of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0059] In one embodiment, the positive electrode film layer mainly consists of the positive electrode material, adhesive, and conductive agent according to the present application. Optionally, the conductive agent includes, but is not limited to, at least one of carbon black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. Here, carbon black includes superconducting carbon, acetylene black, or Ketjen black.

[0060] This application does not limit the method for manufacturing the positive electrode plate, and it can be manufactured using conventional methods. For example, a positive electrode material, a conductive agent, an adhesive, and any other components can be dispersed in a solvent to form a positive electrode slurry, the slurry can be applied to a positive electrode current collector, and a positive electrode plate can be obtained through processes such as drying and cold rolling. The solvent can optionally include, but is not limited to, N-methylpyrrolidone.

[0061] This application provides a lithium-ion battery equipped with a positive electrode plate as described above.

[0062] The lithium-ion battery mainly consists of a positive electrode plate, a negative electrode plate, a separator, and an electrolyte. Any commercially available negative electrode plate (or negative electrode material), separator, and electrolyte can be used, and this application does not limit them.

[0063] The present invention further provides an electrical device equipped with a lithium-ion battery as described above.

[0064] The above-mentioned electrical devices include, but are not limited to, any devices that use the above-mentioned lithium-ion batteries, such as electric vehicles, power tools, electronic products, energy storage systems, and office equipment.

[0065] The oxide precursor, its manufacturing method, and applications will be further described below using the following specific examples. However, those skilled in the art will understand that the following examples are merely illustrative and should not be considered to limit the scope of the present invention. Unless otherwise specified in the examples, the usual conditions or conditions recommended by the manufacturer shall be followed. Unless otherwise specified in the manufacturer of the reagents or equipment used, commercially available and common ones shall be used.

[0066] Example 1 Nickel, cobalt, and manganese acetates and strontium chloride were prepared as aqueous solutions with a total element concentration of 2 mol / L in a metal element molar ratio Ni:Co:Mn:Sr = 8:1:1:0.01. These solutions were then carried out in parallel flow in a reaction vessel with a 10 mol / L sodium hydroxide aqueous solution at 25°C for 8 hours under constant temperature stirring. The hydroxide precipitate produced by the reaction was filtered, washed, dried, and sieved, then packed into saggars and sintered in an atmospheric furnace. The reaction gas was pure oxygen gas at a flow rate of 5 L / min, and the hydroxide filling rate in the furnace was 20%. The sintering conditions were maintained at 350°C for 6 hours. Finally, a strontium-doped oxide precursor with a nickel-cobalt-manganese molar ratio of 8:1:1 was obtained. Analysis using inductively coupled plasma atomic emission spectrometry (ICP-OES / AES) revealed that the oxide precursor was chemically charged. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.001 O 1.001 It was confirmed that this was the case. The oxide precursor produced in this example and lithium hydroxide monohydrate were thoroughly mixed in a high-speed mixer at 500 rpm for 30 minutes in a ratio of 1:1.01 for the molar amount of the main group element metal to the molar amount of lithium to obtain a mixture. The mixture was fired at a high temperature in a box-type furnace under an oxygen atmosphere, maintained at 800°C for 16 hours, and then allowed to cool naturally to room temperature. The cathode material was then obtained by crushing and sieving.

[0067] Example 2 The difference between Example 2 and Example 1 is that nickel, cobalt, manganese acetates, and strontium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L, using a metal element molar ratio of Ni:Co:Mn:Sr = 8:1:1:0.02. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.002 O 1.002 It was confirmed that this was the case.

[0068] Example 3 The difference between Example 3 and Example 1 is that nickel, cobalt, manganese acetates, and strontium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L, using a metal element molar ratio of Ni:Co:Mn:Sr = 8:1:1:0.05. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.005 O 1.005 It was confirmed that this was the case.

[0069] Example 4 The difference between Example 4 and Example 1 is that nickel, cobalt, manganese acetates, and strontium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L, using a metal element molar ratio of Ni:Co:Mn:Sr = 6:1:3:0.02. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.6 Co 0.1 Mn 0.3 Sr 0.002 O 1.002 It was confirmed that this was the case.

[0070] Example 5 The difference between Example 5 and Example 1 is that nickel, cobalt, aluminum acetates, and strontium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L, using a metal element molar ratio of Ni:Co:Al:Sr = 8:1:1:0.02. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Al 0.1 Sr 0.002 O 1.002 It was confirmed that this was the case.

[0071] Example 6 The difference between Example 6 and Example 1 is that nickel, cobalt, manganese acetates, and yttrium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L, using a metal element molar ratio of Ni:Co:Mn:Y = 8:1:1:0.02. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Y 0.002 O 1.003 It was confirmed that this was the case.

[0072] Example 7 The difference between Example 7 and Example 1 is that nickel, cobalt, manganese acetates and barium chloride were prepared in an aqueous solution with a total element concentration of 2 mol / L at a metal element molar ratio of Ni:Co:Mn:Ba = 8:1:1:0.02. From the analysis results by an inductively coupled plasma optical emission spectrometer (ICP-OES / AES), the chemical formula of the oxide precursor academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Ba 0.002 O 1.002 was confirmed to be as such.

[0073] Example 8 The difference between Example 8 and Example 1 is that nickel, cobalt, manganese acetates and cerium chloride were prepared in an aqueous solution with a total element concentration of 2 mol / L at a metal element molar ratio of Ni:Co:Mn:Ce = 8:1:1:0.02. From the analysis results by an inductively coupled plasma optical emission spectrometer (ICP-OES / AES), the chemical formula of the oxide precursor academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Ce 0.002 O 1.004 was confirmed to be as such.

[0074] Example 9 The difference between Example 9 and Example 2 is that the temperature of the coprecipitation reaction is 35°C.

[0075] Example 10 The difference between Example 10 and Example 2 is that the temperature of the coprecipitation reaction is 45°C.

[0076] Example 11 The difference between Example 11 and Example 2 is that the time of the coprecipitation reaction is 3 h.

[0077] Example 12 The difference between Example 12 and Example 2 is that the time of the coprecipitation reaction is 5 h.

[0078] Example 13 The difference between Example 13 and Example 2 is that the coprecipitation reaction time is 10 hours.

[0079] Example 14 The difference between Example 14 and Example 2 is that the sintering temperature is 250°C.

[0080] Example 15 The difference between Example 15 and Example 2 is that the sintering temperature is 550°C.

[0081] Example 16 The difference between Example 16 and Example 2 is that the sintering time is 2 hours.

[0082] Example 17 The difference between Example 17 and Example 2 is that the sintering time is 4 hours.

[0083] Example 18 The difference between Example 18 and Example 2 is that the sintering time is 8 hours.

[0084] Example 19 The difference between Example 19 and Example 2 is that the reaction gas used for sintering is air with an oxygen content of 21%. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.002 O 0.6 It was confirmed that this was the case.

[0085] Example 20 The difference between Example 20 and Example 2 is that the reaction gas used for sintering is air with an oxygen content of 50%. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.002 O0.8 It was confirmed that this was the case.

[0086] Example 21 The difference between Example 21 and Example 2 is that the flow rate of pure oxygen is 1 L / min. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.002 O 0.9 It was confirmed that this was the case.

[0087] Example 22 The difference between Example 22 and Example 2 is that the flow rate of pure oxygen is 30 L / min. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.002 O 1.6 It was confirmed that this was the case.

[0088] Example 23 The difference between Example 23 and Example 2 is that the packing rate of hydroxide in the furnace body is 5%. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.002 O 0.95 It was confirmed that this was the case.

[0089] Example 24 The difference between Example 24 and Example 2 is that the packing rate of hydroxide in the furnace body is 35%. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co0.1 Mn 0.1 Sr 0.002 O 1.2 It was confirmed that this was the case.

[0090] Example 25 The difference between Example 25 and Example 1 is that nickel, cobalt acetates, and potassium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L, using a metal element molar ratio of Ni:Co:K = 0.04:0.96:0.015. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.04 Co 0.96 K 0.015 O 1.0075 It was confirmed that this was the case.

[0091] Example 26 The difference between Example 26 and Example 1 is that nickel, manganese acetate, and cesium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L, using a metal element molar ratio of Ni:Mn:Cs = 0.04:0.96:0.015. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.04 Mn 0.96 Cs 0.015 O 1.0075 It was confirmed that this was the case.

[0092] Example 27 The difference between Example 27 and Example 1 is that nickel, manganese, aluminum acetates, and rubidium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L using a metal element molar ratio of Ni:Mn:Al:Rb = 0.5:0.35:0.15:0.01. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.5 Mn 0.35 Al 0.15 Rb 0.01 O 1.005 It was confirmed that this was the case.

[0093] Example 28 The difference between Example 28 and Example 1 is that nickel, cobalt, manganese, aluminum acetates, and strontium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L in the metal element molar ratio Ni:Co:Mn:Al:Sr = 0.96:0.02:0.01:0.01:0.001. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.96 Co 0.02 Mn 0.01 Al 0.01 Sr 0.001 O 1.001 It was confirmed that this was the case.

[0094] Comparative Example 1 A mixed salt solution of Ni, Co, and Mn was prepared in a molar ratio of 8:1:1 to obtain solution A with a concentration of 2 mol / L. A mixed salt solution of Ni, Co, Mn, and Sr was prepared in a molar ratio of 8:1:1:0.02 to obtain solution B with a concentration of 2 mol / L. Solution A, an ammonia aqueous complexing agent, and a sodium hydroxide precipitant were flowed in parallel in a reaction vessel, and the pH value during the reaction process was controlled under heating and stirring conditions to generate precursor C by coprecipitation. Next, solution B, an ammonia aqueous complexing agent, and a sodium hydroxide precipitant were flowed in parallel in a reaction vessel, and the pH value during the reaction process was controlled under heating and stirring conditions to continue growing precursor C particles. After reaching the target particle size, the strontium-doped oxide precursor was obtained through filtration, washing, drying, and sieving. Analysis results by inductively coupled plasma atomic emission spectrometry (ICP-OES / AES) showed that the oxide precursor was chemically charged. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.001 O 1.002 It was confirmed that this was the case. The oxide precursor produced in the comparative example and lithium hydroxide monohydrate were thoroughly mixed in a high-speed mixer at 500 rpm for 30 minutes in a ratio of 1:1.01 for the molar amount of the main group element metal to the molar amount of lithium to obtain a mixture. The mixture was calcined at high temperature in a box-type furnace under an oxygen atmosphere, maintained at 800°C for 16 hours, then allowed to cool naturally to room temperature, and crushed and sieved to obtain the cathode material.

[0095] Comparative Example 2 A mixed salt solution of Ni, Co, and Mn was prepared in a molar ratio of 8:1:1 to obtain solution A with a concentration of 2 mol / L. A portion of solution A, an ammonia aqueous complexing agent, and sodium hydroxide were flowed in parallel in a reaction vessel, and the pH value during the reaction process was controlled under heating and stirring conditions to produce precursor C by coprecipitation. The remaining solution A, an ammonia aqueous complexing agent, and sodium hydroxide precipitant were flowed in parallel in the reaction vessel, and the pH value during the reaction process was controlled under heating and stirring conditions to continue growing precursor C particles. After reaching the target particle size, the ternary oxide precursor was obtained through filtration, washing, drying, and sieving. Analysis results using inductively coupled plasma atomic emission spectrometry (ICP-OES / AES) were obtained to determine the chemical composition of the oxide precursor. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 It was confirmed to be O1. The oxide precursor, lithium hydroxide monohydrate, and strontium chloride produced in the comparative example were thoroughly mixed in a high-speed mixer at 500 rpm for 30 minutes in a molar ratio of 1:1.01:0.001 to obtain a mixture. The mixture was calcined at high temperature in a box-type furnace under an oxygen atmosphere, maintained at 800°C for 16 hours, then allowed to cool naturally to room temperature, and crushed and sieved to obtain the cathode material.

[0096] Comparative Example 3 The difference between Comparative Example 3 and Example 1 is that nickel, manganese, aluminum acetates, and strontium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L, using a metal element molar ratio of Ni:Mn:Al:Sr = 7:1:2:0.01. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni0.7 Mn 0.1 Al 0.2 Sr 0.001 O 1.001 It was confirmed that this was the case.

[0097] Comparative Example 4 The difference between Comparative Example 4 and Example 1 is that nickel, cobalt, manganese acetates, and strontium chloride were prepared as aqueous solutions with a total elemental concentration of 2 mol / L, using a metal element molar ratio of Ni:Co:Mn:Sr = 8:1:1:0.2. Analysis results from inductively coupled plasma atomic emission spectrometer (ICP-OES / AES) showed that the oxide precursor was chemically modified. academic ceremony is Ni 0.8 Co 0.1 Mn 0.1 Sr 0.02 O 1.02 It was confirmed that this was the case.

[0098] Tests were conducted on the oxide precursors produced in Examples 1 to 28 and Comparative Examples 1 to 4, and the results are shown in Figures 1 to 2 and Tables 1 to 3. [Table 1] [Table 2] [Table 3]

[0099] Tests were conducted on the cathode materials manufactured in Examples 1 to 28 and Comparative Examples 1 to 4, and the results are shown in Table 4. [Table 4]

[0100] Application examples The positive electrode materials produced in Examples 1 to 28 and Comparative Examples 1 to 4 are each manufactured into button-type half-cells, and the button-type half-cells are manufactured by a method including the following steps.

[0101] Cathode active material: Conductive carbon black SP (particle size 40 nm):PVDF (molecular weight 900,000) = 90%:5%:5% was dissolved in n-methyl-1,2-pyrrolidone solvent (NMP) and dried in a drying room (dew point temperature -45°C, room area 15 m²). 2 Stir with ) to obtain a uniform positive electrode slurry. Positive electrode slurry This was applied to an aluminum foil current collector (12 μm thick, 99.5% purity) and a diameter of 12 mm. disk Cut into pieces, with a mass load of 8.5 ± 0.15 mg / cm². 2 A positive electrode plate was formed, and a lithium metal disc with a diameter of 11 mm (thickness 0.3 mm, purity 99.9%) was used as the counter electrode. 1 mol / L of LiPF6 ethyl carbonate / diethyl carbonate (EC / DEC, volume 1:1, H2O < 10 ppm) was used as the electrolyte. The battery (water and oxygen content less than 0.1 ppm each) was assembled in a glove box filled with argon gas to create a 2032 type button cell half-cell.

[0102] The assembled batteries were subjected to the following performance tests, and the test results are shown in Table 5. (1) Cycle performance test: Charge the battery at 1C and discharge it at 1C. Perform charge-discharge cycles with a cutoff current of 0.05C and an ambient temperature of 25℃±2℃, keeping the voltage range at 2.8V-4.25V. After 100 cycles, calculate the battery's capacity retention rate. The capacity retention rate is the ratio of the discharge capacity at the 100th cycle to the discharge capacity at the 1st cycle. (2) Discharge capacity: The capacity per gram was tested by charging and discharging at 0.2C, with a test voltage range of 2.8V-4.25V. [Table 5]

[0103] Any combination of the technical features of the above embodiments is possible. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described, but as long as these combinations of technical features are inconsistent, they are all considered to be within the scope described herein.

[0104] The above embodiments illustrate only a few embodiments of the present application, and although the descriptions are specific and detailed, they should not be interpreted as limiting the scope of the patent. A person skilled in the art could make several modifications and improvements without departing from the spirit of the present application, and all of these would be considered to fall within the scope of protection. Therefore, the scope of protection of the patent of the present application should be based on the attached claims.

[0105] This application claims priority to a Chinese patent application filed with the China National Intellectual Property Administration on December 20, 2023, application number 202311756250.3, with the title of the invention "Oxide Precursor, Method for Producing the Same, and Applications," the entirety of which is incorporated into this application by reference.

Claims

1. An oxide precursor, wherein the general chemical formula of the oxide precursor is Ni ｘ Co ｙ Mn ｚ Al ｄ M ｅ O ｎ Therefore, 0 < x ≤ 0.96, 0 ≤ y ≤ 0.96, 0 ≤ z ≤ 0.96, 0 ≤ d ≤ 0.15, 0 < e ≤ 0.015, 0.6 ≤ n ≤ 1.6, x + y + z + d = 1, and y, z, and d are not simultaneously 0, and the ionic radius of the metal element M is ≥ 0.08 nm. An oxide precursor wherein the uniformity of the distribution of the metal element M in the oxide precursor is 98.5% or more.

2. D of the oxide precursor ５０ The oxide precursor according to claim 1, wherein the particle size is ≤2 μm.

3. The oxide precursor according to claim 1, wherein the crystal lattice parameters of nickel oxide in the oxide precursor satisfy 2.9553 Å ≤ a ≤ 2.9702 Å, 2.9553 Å ≤ b ≤ 2.9702 Å, and 7.2285 Å ≤ c ≤ 7.2425 Å.

4. The oxide precursor according to claim 1, wherein, in the X-ray diffraction spectrum, the ratio of the (012) crystal plane diffraction peak intensity to the (101) crystal plane diffraction peak intensity is 1:1 to 2:

1.

5. The oxide precursor according to claim 1, wherein, in the X-ray diffraction spectrum, the (012) crystal plane diffraction peak of the oxide precursor is shifted to a smaller angle compared to the (012) crystal plane diffraction peak of standard nickel oxide, and the amount of shift is 3° or less.

6. The oxide precursor according to claim 1, wherein the metal element M is selected from at least one of Ca, Sn, Cd, Ba, Y, Ag, Sr, Cs, K, Na, In, Ce, Tl, Bi, Sc, Yb, Tm, Er, Te, or Pd.

7. The aforementioned oxide precursor is (1) Bulk density of the oxide precursor ≥ 0.4 g / cm³ ３ The condition, (2) D of the oxide precursor １０ The condition that it is ≦ 0.5 μm, (3) D of the oxide precursor ９０ The condition is ≤10 μm, (4) The particle size distribution span value of the oxide precursor is ≤ 5, and the particle size distribution span value is (D ９０ -D １０ ) / D ５０ An oxide precursor according to claim 1, satisfying at least one of the following conditions.

8. The oxide precursor according to claim 1, wherein the overall distribution uniformity of the elements Ni, Co, Mn, and Al in the oxide precursor is 98% or more.

9. A method for producing an oxide precursor according to any one of claims 1 to 8, Ni ｘ Co ｙ Mn ｚ Al ｄ M ｅ O ｎ Based on the criteria that 0 < x ≤ 0.96, 0 ≤ y ≤ 0.96, 0 ≤ z ≤ 0.96, 0 ≤ d ≤ 0.15, 0 < e ≤ 0.015, 0.6 ≤ n ≤ 1.6, x + y + z + d = 1, and y, z, and d are not all 0, a mixed metal salt solution is prepared and a coprecipitation reaction is carried out with the precipitant solution to obtain D ５０ A process to obtain a hydroxide with a size of 0.2 μm - 1 μm, A method for producing an oxide precursor, comprising the step of sintering the hydroxide to obtain the oxide precursor.

10. The aforementioned coprecipitation reaction is (1) The condition that the molar ratio of metal ions in the mixed metal salt solution to hydroxide ions in the precipitant solution is 1:1 to 1:1.15, (2) Under the condition that the total concentration of the mixed metal salts in the mixed metal salt solution is 0.5 mol / L to 3 mol / L, (3) Under the condition that the concentration of the precipitant in the precipitant solution is 0.5 mol / L to 6 mol / L, (4) The condition that the precipitant in the precipitant solution is selected from at least one of potassium hydroxide, sodium hydroxide, or lithium hydroxide, (5) The method for producing an oxide precursor according to claim 9, wherein the temperature of the coprecipitation reaction is 25°C to 45°C and the duration is 3h to 10h, satisfying at least one of these conditions.

11. The step of sintering the hydroxide precipitate is: (1) Under the condition that the volume of the hydroxide is 5% to 35% of the sintering reaction space volume, (2) The sintering is carried out in an oxygen-containing gas, the oxygen content in the oxygen-containing gas is 21% or more, and the flow rate of the oxygen-containing gas is 1 L / min to 30 L / min. (3) The method for producing an oxide precursor according to claim 9, wherein the sintering temperature is 350°C to 650°C and the time is 1 hour to 6 hours, satisfying at least one of these conditions.

12. A cathode material manufactured by an oxide precursor according to any one of claims 1 to 8, wherein the uniformity of the distribution of metal element M in the cathode material is 98.5% or more.

13. The positive electrode material according to claim 12, wherein the molar amount of metal element M is 0.01 mol% to 1.5 mol% of the molar amount of other metal elements in the positive electrode material excluding Li and element M.

14. A positive electrode plate comprising the positive electrode material according to claim 12 or claim 13.

15. A lithium-ion battery comprising the positive electrode plate described in claim 14.

16. An electrical device comprising the lithium-ion battery described in claim 15.

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