Positive electrode active material and method for manufacturing the same, positive electrode plate, battery and electrical equipment

Abstract

This application discloses a positive electrode active material, a method for manufacturing the same, a positive electrode plate, a battery, and an electric device. The positive electrode active material is a secondary particle, and the equivalent sheet layer number R of the (003) crystal plane of the positive electrode active material (003) and the equivalent sheet layer number R of the (104) crystal plane (104) are such that R (104) / R (003) is 1.4 to 1.8, 【Number 12】 JPEG2026521086000019.jpg18170 is satisfied, where A (003) is the average thickness perpendicular to the direction of the (003) crystal plane in the positive electrode active material microcrystal, with the unit of nm, and B (003) is the spacing of the (003) crystal plane in the positive electrode active material microcrystal, with the unit of nm, and A (104) is the average thickness perpendicular to the direction of the (104) crystal plane in the positive electrode active material microcrystal, with the unit of nm, and B (104) is the spacing of the (104) crystal plane in the positive electrode active material microcrystal, with the unit of nm.

Description

[Technical Field]

[0001] This application relates to the field of batteries, specifically to positive electrode active materials and methods for producing the same, positive electrode plates, batteries, and electrical equipment. [Background technology]

[0002] Lithium-ion batteries are widely used in various consumer electronics products and electric vehicles due to their outstanding features such as being lightweight, pollution-free, and having no memory effect. However, during the charge-discharge cycle, the release and absorption of lithium ions in the positive electrode active material causes the positive electrode active material to contract and expand, making it prone to cracking. This reduces the structural stability of the material, which in turn degrades the battery's cycle performance. [Overview of the Initiative] [Problems that the invention aims to solve]

[0003] The purpose of this application is to solve, at least to some extent, one of the technical problems in related technologies. Therefore, one objective of this application is to propose a positive electrode active material, a method for manufacturing the same, a positive electrode plate, a battery, and electrical equipment, and that by using this positive electrode active material, a battery containing it can have excellent cycle performance. [Means for solving the problem]

[0004]

number

[0005] The positive electrode active material according to the embodiment of this application has the (003) equivalent number of crystal plane sheets R (003) (104) Equivalent number of crystal planes R (104) R (104) / R (003)Satisfies that it is 1.4 - 1.8, the primary particles in the positive electrode active material are arranged in a divergent manner, and have regular grain boundaries and a low crystal plane density. During the charge-discharge process, the primary particles contract and expand in the c-axis direction, and align with the grain boundary lines, which can not only effectively release the expansion stress generated during the charge-discharge process, but also prevent the generation of microcracks between interfaces, and greatly improve the stability of the positive electrode active material. Thereby, by adopting the positive electrode active material of the present application, the battery containing it can have excellent cycle performance.

[0006] In addition, the positive electrode active material according to the above embodiment of the present application may have the following additional technical features

[0007] In some embodiments of the present application, R (104) / R (003) is 1.55 - 1.75. Thereby, the cycle performance of the battery can be further improved.

[0008] In some embodiments of the present application, the number of equivalent sheet layers R of the (003) crystal plane of the positive electrode active material (003) is 80 - 130.

[0009] In some embodiments of the present application, the number of equivalent sheet layers R of the (003) crystal plane of the positive electrode active material (003) is 90 - 120.

[0010] In some embodiments of the present application, the number of equivalent sheet layers R of the (104) crystal plane of the positive electrode active material (104) is 140 - 210.

[0011] In some embodiments of the present application, the number of equivalent sheet layers R of the (104) crystal plane of the positive electrode active material (104) is 150 - 200.

[0012]

Number

[0013]

Number

[0014] In some embodiments of the present application, the average thickness A perpendicular to the direction of the (003) crystal plane in the positive electrode active material microcrystal is (003) The range is 35nm-55nm.

[0015] In some embodiments of the present application, the average thickness A perpendicular to the direction of the (003) crystal plane in the positive electrode active material microcrystal is (003) The range is 40nm-55nm.

[0016] In some embodiments of the present application, the spacing B of the (003) crystal planes of the positive electrode active material (003) The range is 0.4730nm-0.4760nm.

[0017] In some embodiments of the present application, the spacing B of the (003) crystal planes of the positive electrode active material (003) The range is 0.4735nm-0.4750nm.

[0018]

number

[0019]

number

[0020] In some embodiments of the present application, the average thickness A perpendicular to the direction of the (104) crystal plane in the positive electrode active material microcrystal is (104) The range is 25nm-55nm.

[0021] In some embodiments of the present application, the average thickness A perpendicular to the direction of the (104) crystal plane in the positive electrode active material microcrystal is (104) The range is 30nm-50nm.

[0022] In some embodiments of the present application, the spacing B of the (104) crystal planes of the positive electrode active material (104) The range is 0.2030nm-0.2040nm.

[0023] In some embodiments of the present application, the spacing B of the (104) crystal planes of the positive electrode active material (104) The range is 0.2035nm-0.2040nm.

[0024] In some embodiments of the present application, the aspect ratio of the primary particles of the positive electrode active material is 2-5:1. This further improves the battery's cycle performance.

[0025] In some embodiments of the present application, the aspect ratio of the primary particles of the positive electrode active material is 2-4:1. This further improves the battery's cycle performance.

[0026] In some embodiments of this application, the cross-sectional porosity of the positive electrode active material is 2%-10%. This further improves the battery's cycle performance.

[0027] In some embodiments of this application, the cross-sectional porosity of the positive electrode active material is 3%-8%. This further improves the battery's cycle performance.

[0028] In some embodiments of the present application, the BET specific surface area of ​​the positive electrode active material is 0.4 m². 2 / g-0.9m 2 This is / g. This further improves the battery's cycle performance.

[0029] In some embodiments of the present application, the BET specific surface area of ​​the positive electrode active material is 0.5 m². 2 / g-0.8m 2 This is / g. This further improves the battery's cycle performance.

[0030] In some embodiments of the present application, the positive electrode active material includes a substrate, wherein the substrate is Li 1+a Ni x Co y Mn z M mThe molecule contains O2, and satisfies -0.05 ≤ a ≤ 0.3, 0.8 ≤ x ≤ 1, 0 ≤ y ≤ 0.2, 0 ≤ z ≤ 0.2, and 0.002 ≤ m ≤ 0.01, where M contains at least one of Sn, W, V, Mo, P, and B. This can further improve the battery's cycle performance.

[0031] In some embodiments of the present application, M further comprises at least one of Sb, Nb, Mg, La, Ti, Al, Sr, Ba, Y, Zr, Ca, Fe, S, Zn, and Ta.

[0032] In some embodiments of the present application, the positive electrode active material further comprises a coating layer formed on at least a portion of the surface of the substrate, the coating layer containing element J, and element J comprising at least one of Al, Zr, Ti, F, B, Cl, Br, I, S, W, Co, Sn, and Mo. This further improves the cycle performance of the battery.

[0033] In a second aspect of the present application, the present application proposes a method for producing the above-mentioned positive electrode active material. A step of providing a cathode active material precursor, The process includes the step of first mixing and sintering the positive electrode active material precursor, a lithium source, and a dopant containing element M to obtain a positive electrode active material-fired material.

[0034] As a result, the positive electrode active material obtained by this method has excellent cycle performance in a battery containing it.

[0035] In some embodiments of the present application, the positive electrode active material precursor is produced by the following method, in which a nickel salt, a cobalt salt, a manganese salt, a precipitating agent, and a complexing agent are mixed and subjected to a coprecipitation reaction to obtain the positive electrode active material precursor, where the temperature of the coprecipitation reaction is 50°C-80°C, and the ammonia content during the coprecipitation reaction is 2 g / L-8 g / L.

[0036] In some embodiments of the present invention, the temperature of the coprecipitation reaction is 55°C-75°C, and the ammonia content in the coprecipitation reaction process is 3g / L-7g / L.

[0037] In some embodiments of the present application, the positive electrode active material precursor is The Dv50 of the positive electrode active material precursor is 9 μm-20 μm. The number of equivalent (101) crystal plane sheets R of the positive electrode active material precursor (101) and the equivalent number of crystal planes R of the positive electrode active material precursor (001) R (101) / R (001) The condition that is 2.0-3.0, The peak intensity ratio I of the positive electrode active material precursor (101) / I (001) It satisfies at least one of the following conditions: it is between 0.7 and 1.4.

[0038] This will further improve the battery's cycle performance.

[0039] In some embodiments of the present application, the peak intensity ratio of the positive electrode active material precursor I (101) / I (001) The range is 0.8-1.2.

[0040] In some embodiments of the present invention, the temperature of the first mixed sintering is 650°C-900°C, and the time is 4h-15h.

[0041] In some embodiments of the present application, the method further includes a step of second mixing and sintering the positive electrode active material-fired material and an element J-containing coating to form an element J-containing coating layer on at least a portion of the surface of the positive electrode active material-fired material. This can further improve the battery's cycle performance.

[0042] In some embodiments of the present invention, the temperature of the second mixed sintering is 200°C-700°C, and the time is 3h-10h.

[0043] In a third aspect of the present application, the present application proposes a positive electrode plate comprising a positive electrode active material described in the first aspect of the present application or a positive electrode active material obtained by the method described in the second aspect of the present application. As a result, a battery comprising the same has excellent cycle performance.

[0044] In a fourth aspect of the present application, the present application proposes a battery comprising the positive electrode plate described in the third aspect of the present application, thereby providing the battery with excellent cycle performance.

[0045] In a fifth aspect of the present application, the present application proposes an electrical device including the battery described in the fourth aspect of the present application.

[0046] Additional aspects and advantages of the present invention are shown in part in the following description, some of which become apparent from the following description, or are understood through the practice of the present invention. [Modes for carrying out the invention]

[0047] The embodiments of the present application will be described in detail below. Examples relating to the embodiments are shown in the drawings, and the same or similar reference numerals consistently indicate the same or similar elements or elements having the same or similar function. The embodiments described below with reference to the drawings are illustrative and intended to illustrate the present application, and should not be construed as limiting the present application.

[0048] The endpoints and any values ​​of the ranges disclosed herein should be understood to include values ​​close to such exact ranges or values, and not to be limited to such exact ranges or values. In the case of numerical ranges, the intervals between the endpoint values ​​of each range, between the endpoint values ​​of each range and individual point values, and between individual point values ​​combine to obtain one or more new numerical ranges, and these numerical ranges shall be deemed to be specifically disclosed in the specification.

[0049]

number

[0050] The inventors have found that the number of equivalent crystal plane sheets in a layered positive electrode active material represents the size of the R-3m structure, and that for a layered positive electrode active material, the statistical number of layered layers in a certain direction can reflect the average number of lattice sites in that direction. For a layered positive electrode active material, the number of equivalent crystal plane sheets in each direction can truly reflect the number of active lithium sites that a single microcrystal can accommodate, which affects capacity, lithium ion transport pathways, and overall structural stability. During the charge-discharge process, layered positive electrode active materials typically undergo significant contraction and expansion along the c-axis and a-axis, with each layer being a unit. Since the contraction and expansion of the overall microcrystal size is the sum of the degree of structural change within each layer, the number of crystal plane sheets is extremely important for the layered lattice change and expansion stress within the microcrystal, and has a decisive impact on the structural stability of the material. (104) / R (003) The inventors have found that the ratio of the number of sheet layers in the a-axis direction to the c-axis direction can be expressed, and that the c-axis is aligned parallel to the direction from the center to the surface of the secondary particle, while the a-axis extends in the direction from the center to the surface of the secondary particle. Furthermore, the inventors have found that the equivalent number of sheet layers R of the (003) crystal plane of the positive electrode active material (003) (104) Equivalent number of crystal planes R (104) R (104) / R (003) The positive electrode active material satisfies the condition of 1.4-1.8, and the primary particles in the positive electrode active material are arranged divergently, with regular grain boundaries and a low crystal plane density. During the charge and discharge process, the primary particles contract and expand in the c-axis direction, aligning with the grain boundaries. This not only effectively releases the expansion stress generated during the charge and discharge process, but also prevents the formation of microcracks between interfaces, significantly improving the stability of the positive electrode active material. As a result, by adopting the positive electrode active material of this invention, batteries containing it can have excellent cycle performance.

[0051] According to the embodiment of the present application, the number of equivalent sheet layers of the (003) crystal plane of the positive electrode active material is R (003 ) and (104) Equivalent number of crystal planes R (104) is R (104) / R (003)The values ​​satisfy 1.4-1.8, for example, 1.4, 1.45, 1.5, 1.55, 1.6, 1.65, 1.7, 1.75, 1.8, etc., and according to the specific embodiments of this application, R (104) / R (003) The value is 1.55-1.75. This further improves the stability of the positive electrode active material, thereby improving the battery's cycle performance.

[0052] According to the embodiment of the present application, the number of equivalent sheet layers of the (003) crystal plane of the positive electrode active material is R (003) The (003) equivalent sheet layer number R of the positive electrode active material is 80-130, for example, 80, 90, 100, 110, 120, 130, etc. (003) The range is 90-120, and the number of equivalent (104) crystal plane sheets R of the positive electrode active material (104) The (104) equivalent sheet layer number R of the positive electrode active material is 140-210, for example, 140, 150, 160, 170, 180, 190, 200, 210, etc. (104) The range is 150-200.

[0053] The inventors have found that when the number of equivalent sheet layers of the (003) crystal plane of the positive electrode active material is within the above range, there are sufficient lithium sites in the overall layered frame, providing space to accommodate active lithium and allowing for the maximum reversible gram capacity to be obtained. At the same time, it exhibits a stabilizing effect against expansion and contraction of the c axis during the charge-discharge process, mitigating distortion and collapse of the material structure and conferring excellent cycle stability to the material. The number of equivalent sheet layers of the (104) crystal plane of the positive electrode active material can indirectly reflect the number of layers in the a-axis direction, represent the size of the planar layers, determine the number of lithium ion sites that can be accommodated in each planar layer, and determine the length of the solid phase transfer path when lithium ions are intercalated and released within the layer. When the number of equivalent sheet layers of the (104) crystal plane of the positive electrode active material is within the above range, the material can be given maximum reversible capacity and high rate performance. Thus, the present invention relates to the R of the positive electrode active material. (003) and R (104) By controlling it within the above range, the battery's energy density, cycle performance, rate performance, and safety performance can be further improved.

[0054]

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[0055]

number

[0056] According to the embodiment of the present invention, the average thickness A perpendicular to the direction of the (003) crystal plane in the positive electrode active material microcrystal (003) The wavelength is 35nm-55nm, for example, 35nm, 40nm, 45nm, 50nm, 55nm, etc. Furthermore, the average thickness A perpendicular to the direction of the (003) crystal plane in the positive electrode active material microcrystal is also included. (003) This is 40nm-55nm. This results in an average thickness A perpendicular to the direction of the (003) crystal plane in the positive electrode active material microcrystal. (003) By satisfying the above range, the material will have an appropriate microcrystal size in the c-axis direction, ensuring normal reversible capacity release, and will also have a certain stabilizing effect when expansion and contraction occur in the c-axis direction, thereby giving the material excellent overall performance in terms of capacity and cycles.

[0057] According to the embodiment of the present application, the spacing B of the (003) crystal planes of the positive electrode active material (003) The wavelength is 0.4730nm-0.4760nm, for example, 0.4730nm, 0.4735nm, 0.4740nm, 0.4745nm, 0.4750nm, 0.4755nm, 0.4760nm, etc. Furthermore, the spacing B of the (003) crystal planes of the positive electrode active material (003) This is 0.4735 nm - 0.4750 nm. This results in the spacing B of the (003) crystal planes of the positive electrode active material. (003) By satisfying the above range, it is advantageous for rapid intercalation and deintercalation of lithium ions, improving the rate performance of the material, while providing a certain space for the contraction and expansion of crystal cells in the c-axis direction, reducing lattice strain and microcrystalline minute stresses, and improving material stability.

[0058] According to the embodiment of the present invention, the average thickness A perpendicular to the direction of the (104) crystal plane in the positive electrode active material microcrystal (104) The wavelength is 25nm-55nm, for example, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, etc. Furthermore, the average thickness A perpendicular to the direction of the (104) crystal plane in the positive electrode active material microcrystal is also included. (104) This is 30nm-50nm. This results in an average thickness A perpendicular to the direction of the (10⁴) crystal plane in the positive electrode active material microcrystal. (104) By satisfying the above range, the material is guaranteed to have an appropriate microcrystal size in the a-axis direction, an appropriate size active structure and lithium ion migration pathway, and high capacity and good rate performance.

[0059] According to the embodiment of the present application, the spacing B of the (104) crystal planes of the positive electrode active material (104) The wavelength is 0.2030nm-0.2040nm, for example, 0.2030nm, 0.2032nm, 0.2035nm, 0.2037nm, 0.2039nm, 0.2040nm, etc. Furthermore, the spacing B of the (104) crystal planes of the positive electrode active material (104) The wavelength is 0.2035 nm - 0.2040 nm. This results in the spacing B of the crystal planes where the positive electrode active material is located. (104) When the above range is satisfied, it is advantageous for rapid intercalation and deintercalation of lithium ions, reduces the contraction of crystal cells in the a-axis direction, and improves the rate performance and cycle stability of the material.

[0060] According to the embodiments of the present application, the aspect ratio of the primary particles of the positive electrode active material is 2-5:1, for example, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, etc. Furthermore, the aspect ratio of the primary particles of the positive electrode active material is 2-4:1.

[0061] According to the embodiments of the present application, the cross-sectional porosity of the positive electrode active material is 2%-10%, for example, 2%, 5%, 7%, 9%, 10%, etc. Furthermore, the cross-sectional porosity of the positive electrode active material is 3%-8%.

[0062] According to the embodiment of the present application, the BET specific surface area of ​​the positive electrode active material is 0.4 m². 2 / g-0.9m 2 / g, for example 0.4m 2 / g, 0.5m 2 / g, 0.6m 2 / g, 0.7m 2 / g, 0.8m 2 / g, 0.9m 2 The values ​​are such as / g, and furthermore, the BET specific surface area of ​​the positive electrode active material is 0.5m². 2 / g-0.8m 2 It is / g.

[0063] Under the aspect ratio of the primary particles described above, the primary particles exhibit a more elongated morphology, the a-axis coincides with the direction and height radiating from the center of the secondary particles, and many voids are formed between the primary particles, resulting in a material with a large specific surface area. This secondary particle morphological structure not only mitigates particle expansion and minimizes crack formation, but also prevents side reactions of the electrolyte within the secondary particles, thereby improving the stability of the positive electrode active material.

[0064] In this application, the method for measuring the aspect ratio of primary particles of the positive electrode active material includes acquiring surface electron microscope images with a SEM, identifying the aspect ratio of primary particles in secondary particle spheres using software, and obtaining the average aspect ratio of primary particles.

[0065] In this application, the method for measuring the cross-sectional porosity of the positive electrode active material includes cross-sectional processing of the positive electrode active material and then acquiring a cross-sectional electron microscope image using a scanning electron microscope (SEM). Using software, the image contrast is identified to obtain the pore area and total area, and the ratio of the pore area to the total area is the cross-sectional porosity.

[0066] In the present application, the BET specific surface area of the positive electrode active material can be measured using devices and methods well-known in the art. For example, it can be measured by referring to the following method: Using a multi-station fully automatic specific surface area and pore size distribution analyzer Gemini VII 2390 manufactured by Micromeritics, USA, approximately 7 g of the sample was placed in a long tube with a 9 cc valve, degassed at 200 °C for 2 h, and then placed in the host to measure the data of the BET specific surface area of the positive electrode active material.

[0067] According to an embodiment of the present application, the positive electrode active material includes a substrate, Li 1+a Ni x Co y Mn z M m O2, -0.05 ≤ a ≤ 0.3, 0.8 ≤ x ≤ 1, 0 ≤ y ≤ 0.2, 0 ≤ z ≤ 0.2, 0.002 ≤ m ≤ 0.01, and M includes at least one of Sn, W, V, Mo, P, and B. Thereby, by doping the above M element into the positive electrode active material, the number of equivalent sheet layers of the crystal plane of the positive electrode active material can be controlled, and the cycle performance of the battery can be improved.

[0068] According to some embodiments of the present application, the Li 1+a Ni x Co y Mn z M m a in O2 satisfies -0.05 ≤ a ≤ 0.3. For example, a is -0.05, -0.02, 0, 0.02, 0.05, 0.1, 0.2, 0.3, etc. Thereby, the substrate contains lithium ions with this content, the specific capacity of the positive electrode active material can be improved, and thereby the battery has a high energy density.

[0069] According to some embodiments of the present application, the Li 1+a Ni x Co y Mn z M mIn O2, x, y, z, and m satisfy the following conditions: 0.8 ≤ x ≤ 1, 0 ≤ y ≤ 0.2, 0 ≤ z ≤ 0.2, 0.002 ≤ m ≤ 0.01, for example, x can be 0.8, 0.85, 0.9, 0.95, 1, etc., y can be 0, 0.1, 0.15, 0.2, etc., z can be 0, 0.1, 0.15, 0.2, etc., and m can be 0.002, 0.005, 0.007, 0.01, etc.

[0070] According to some embodiments of the present application, the Li 1+a Ni x Co y Mn z M m The M in O2 can include at least one of Sb, Nb, Mg, La, Ti, Al, Sr, Ba, Y, Zr, Ca, Fe, S, Zn, and Ta. This can further improve the stability of the positive electrode active material and enhance the battery's cycle performance.

[0071] According to embodiments of the present application, the positive electrode active material further includes a coating layer formed on at least a portion of the surface of the substrate, the coating layer containing element J, and element J includes at least one of Al, Zr, Ti, F, B, Cl, Br, I, S, W, Co, Sn, and Mo. By forming an element J-containing coating layer on the outer surface of the substrate, side reactions between the inner core of the positive electrode active material and the electrolyte can be reduced, thereby improving the cycle stability of the positive electrode active material.

[0072] Furthermore, the form in which element J exists in the above coating layer may include oxides and / or lithium oxides, and those skilled in the art can select them as needed, which will not be explained again here.

[0073] In a second aspect of the present application, the present application proposes a method for producing the above-mentioned positive electrode active material. According to an embodiment of the present application, the method includes the following steps: S100: Provides a cathode active material precursor.

[0074] According to the embodiments of this application, the positive electrode active material precursor may be a commercially available product, or it may be manufactured using the following steps.

[0075] Specifically, a nickel salt solution, a cobalt salt solution, and a manganese salt solution are mixed at a molar ratio of x:y:z of nickel element, cobalt element, and manganese element. Next, a precipitating agent (e.g., sodium hydroxide solution) and a complexing agent (e.g., aqueous ammonia) are added and mixed to cause a coprecipitation reaction to obtain a precursor of the positive electrode active material. Here, the temperature of the coprecipitation reaction is 50°C - 80°C, such as 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, 80°C, etc. Furthermore, the temperature of the coprecipitation reaction is 55°C - 75°C, and the ammonia content during the coprecipitation reaction is 2 g / L - 8 g / L, such as 1 g / L, 2 g / L, 3 g / L, 4 g / L, 5 g / L, 6 g / L, 7 g / L, 8 g / L. Furthermore, the ammonia content is 3 g / L - 7 g / L.

[0076] Note that the "ammonia content during the coprecipitation reaction" can be understood as the content of aqueous ammonia in the reaction system when aqueous ammonia is used as a complexing agent for the coprecipitation reaction.

[0077] Thereby, by controlling the coprecipitation temperature and ammonia content, a precursor having a specific number of equivalent sheet layers of crystal planes can be synthesized.

[0078] According to the examples of the present application, the Dv50 of the precursor of the positive electrode active material is 9 μm - 20 μm, such as 9 μm, 10 μm, 12 μm, 15 μm, 18 μm, 20 μm, etc.

[0079] In the present application, Dv50 refers to the particle size corresponding to when the cumulative volume distribution rate reaches 50%, and it is measured by referring to Standard GB / T 19077 - 2016 and using a laser particle size analyzer (e.g., MalverR Master Size 3000).

[0080] According to the examples of the present application, the number of equivalent sheet layers R of the (101) crystal plane of the precursor of the positive electrode active material (101) and the number of equivalent sheet layers R of the (001) crystal plane of the precursor of the positive electrode active material (001) are such that R (101) / R (001)The value is 2.0-3.0, for example, 2, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3, etc., and thereby the number of equivalent (101) crystal plane sheets R of the positive electrode active material precursor is satisfied. (101) and the equivalent number of crystal planes R of the positive electrode active material precursor (001) By satisfying the above range, it becomes easier to obtain a precursor with high crystallinity, exhibit a more regular divergent arrangement, and facilitate the formation of a positive electrode active material with an appropriate number of crystal planes and a structurally regular arrangement through lithiumization recombination during the subsequent pyro-sintering process.

[0081]

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[0082]

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[0083] According to the embodiment of the present application, the peak intensity ratio I of the positive electrode active material precursor (101) / I (001) The peak intensity ratio I of the positive electrode active material precursor is 0.7-1.4, for example, 0.7, 0.8, 1, 1.2, 1.4, etc. (101) / I (001) The range is 0.8-1.2. This ensures that the peak intensity ratio of the positive electrode active material precursor satisfies the above range, resulting in the precursor itself having high crystallinity and improving the stability of the positive electrode active material.

[0084] In this application, the peak intensity I of the positive electrode active material precursor (101) This refers to the peak intensity of the (101) crystal plane characteristic peak in that XRD spectrum, I (001) This refers to the peak intensity of the (001) crystal plane characteristic peak in that XRD spectrum.

[0085] S200: A dopant containing a positive electrode active material precursor, a lithium source, and element M is subjected to a first mixed sintering process.

[0086] According to the embodiment of the present application, the cathode active material precursor obtained in the above step, a lithium source, and a dopant containing element M are subjected to a first mixed sintering in an oxygen-containing atmosphere, where the temperature of the first mixed sintering is 650°C-900°C, for example, the sintering temperatures are 650°C, 680°C, 700°C, 720°C, 750°C, 780°C, 800°C, 820°C, 850°C, 880°C, and 900°C, and the time is 4h-15h, for example, 4h, 6h, 8h, 10h, 12h, 15h, etc. Next, the sintered compound is allowed to cool to room temperature by natural temperature reduction, then crushed, sieved, and iron removed to obtain a cathode active material-fired material. Thus, by selecting a specific doping element M, the growth of microcrystals of the cathode active material in the lithification stage can be controlled, and by combining the above sintering conditions, it is possible to control the number of equivalent crystal plane sheets and the spacing of crystal planes of the cathode active material.

[0087] For example, the nickel salt, cobalt salt, and manganese salt mentioned above may be chlorides, carbonates, and sulfates corresponding to each element, and the lithium source and the dopant containing element M may be at least one of the corresponding chlorides, carbonates, sulfates, and oxides.

[0088] This allows the positive electrode active material to be manufactured and obtained by this method, thereby improving the battery's cycle performance.

[0089] According to the embodiments of the present application, the method for producing the above-mentioned positive electrode active material further includes the following steps.

[0090] S300: The positive electrode active material-fired material and element J-containing coating obtained in step S200 are subjected to a second mixed sintering in an oxygen-containing atmosphere. The temperature of the second mixed sintering is 200°C-700°C, for example, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C, etc., and the time is 3h-10h, for example, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, etc., so that an element J-containing coating layer is formed on at least a portion of the positive electrode active material-fired material surface. Then, the temperature is lowered naturally, and the material is crushed, sieved, and iron removed to obtain the positive electrode active material. By forming an element J-containing coating layer on the outer surface of the positive electrode active material, side reactions between the inner core of the positive electrode active material and the electrolyte are reduced, thereby improving the cycle stability of the positive electrode active material.

[0091] The characteristics and advantages described above for the positive electrode active material also apply to the method for manufacturing the positive electrode active material and will not be repeated here.

[0092] In a third aspect of the present application, the present application proposes a positive electrode plate. According to an embodiment of the present application, the positive electrode plate comprises a positive electrode active material described in the first aspect of the present application or a positive electrode active material obtained by the method described in the second aspect of the present application.

[0093] According to embodiments of the present application, the positive electrode plate includes a positive electrode current collector and a positive electrode active material layer provided on the positive electrode current collector, the positive electrode active material layer includes the positive electrode active material, and the positive electrode current collector may be a metal foil sheet or a composite current collector (a composite current collector may be formed by providing a metal material on a polymer substrate), for example, an aluminum foil may be used for the positive electrode current collector.

[0094] According to some embodiments of the present application, the positive electrode active material layer may optionally contain a binder. For example, the binder may include at least one of polyvinylidene fluoride (PVBF), polytetrafluoroethylene (PTFE), vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, tetrafluoroethylene-hexafluoropropylene copolymer, or fluorine-containing acrylic ester resin.

[0095] According to some embodiments of the present application, the cathode active material layer may optionally contain a conductive agent. For example, the conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, Kocheng black, carbon dots, carbon nanotubes, graphene, or carbon nanofibers.

[0096] According to some embodiments of the present application, a positive electrode plate can be manufactured by the following method: components for manufacturing the positive electrode plate, such as a positive electrode active material, a conductive agent, a binder, and any other components, are dispersed in a solvent (e.g., R-methylpyrrolidone) to form a positive electrode slurry; the positive electrode slurry is applied to a positive electrode current collector; and after processes such as drying and cold pressing, a positive electrode plate can be obtained.

[0097] The features and advantages described above for the positive electrode active material and its manufacturing method also apply to the positive electrode plate and will not be repeated here.

[0098] In a fourth aspect of the present application, the present application proposes a battery. According to an embodiment of the present application, the battery includes the positive electrode plate described above.

[0099] For example, a battery includes a positive electrode plate, a negative electrode plate, an electrolyte, and a separator, with the separator located between the positive and negative electrode plates. During the charging and discharging process of the battery, active ions are intercepted and deintercepted as they travel back and forth between the positive and negative electrode plates. The electrolyte plays the role of conducting ions between the positive and negative electrode plates. The separator is provided between the positive and negative electrode plates and primarily serves to prevent short circuits between the positive and negative electrodes while also allowing ions to pass through.

[0100] According to embodiments of the present application, the negative electrode plate includes a negative electrode current collector and a negative electrode active material layer provided on the negative electrode current collector, the negative electrode active material layer includes a negative electrode active material, the negative electrode current collector may be a metal foil sheet or a composite current collector (a composite current collector may be formed by providing a metal material on a polymer substrate), and for example, copper foil may be used for the positive electrode current collector.

[0101] According to some embodiments of the present application, the negative electrode active material may include at least one of the following materials: artificial graphite, natural graphite, soft carbon, hard carbon, silicon-based materials, tin-based materials, lithium titanate, etc.

[0102] According to some embodiments of the present application, the negative electrode active material layer may optionally contain a conductive agent. The conductive agent may include at least one of superconducting carbon, acetylene black, carbon black, kocheng black, carbon dots, carbon nanotubes, graphene, or carbon nanofibers.

[0103] According to some embodiments of the present application, the negative electrode active material layer may optionally contain other auxiliary agents, such as thickeners (e.g., sodium methylcellulose (CMC-Ra)).

[0104] According to some embodiments of the present invention, a negative electrode plate can be manufactured by the following method: components for manufacturing the negative electrode plate, such as a negative electrode active material, a conductive agent, and an adhesive, are dispersed in a solvent (e.g., a deionized solvent) to form a negative electrode slurry; the negative electrode slurry is applied to a negative electrode current collector; and after processes such as drying and cold pressing, a negative electrode plate can be obtained.

[0105] According to some further embodiments of the present application, the negative electrode plate may include a metallic lithium sheet or a lithium alloy, such as a lithium indium alloy.

[0106] According to several embodiments of the present application, the type of separator is not particularly limited, and any known porous structure separator with excellent chemical and mechanical stability can be arbitrarily selected. For example, the material of the separator may include at least one of glass fiber, nonwoven fabric, polyethylene, polypropylene, or polyvinylidene fluoride. The separator may be a single-layer film or a multilayer composite film, and is not particularly limited. If the separator is a multilayer composite film, the materials of each layer may be the same or different, and are not particularly limited.

[0107] According to some embodiments of the present application, the type of electrolyte is not specifically limited and can be selected as needed. For example, the electrolyte may be liquid, gel, or all-solid. According to some specific embodiments of the present application, the electrolyte is an electrolyte solution containing a lithium salt and a solvent.

[0108] According to some specific examples of the present application, the lithium salt may include at least one of lithium hexafluorophosphate, lithium tetrafluoroborate, lithium perchlorate, lithium hexafluoroarsenate, lithium bisfluorosulfonylimide, lithium bistrifluoromethanesulfonylimide, lithium trifluoromethanesulfonate, lithium difluorophosphate, lithium difluorodisoxalate borate, lithium disoxalate borate, lithium difluorodisoxalate phosphate, or lithium tetrafluorooxalate phosphate.

[0109] According to some specific examples of the present application, the solvent may include at least one of ethylene carbonate, propylene carbonate, ethyl methyl carbonate, diethyl carbonate, dimethyl carbonate, dipropyl carbonate, methyl propyl carbonate, propylene carbonate, butylene carbonate, fluoroethylene carbonate, methyl formate, methyl acetate, ethyl acetate, propyl propionate, methyl propionate, ethyl propionate, propyl propionate, methyl butyrate, ethyl butyrate, 1,4-butyrolactone, sulfolane, dimethyl sulfone, ethylene glycol dimethyl ether, methaneethanesulfone, or ethaneethanesulfone.

[0110] In some embodiments of the present invention, the electrolyte may optionally contain additives. For example, the additives may include additives for negative electrode film formation, additives for positive electrode film formation, and additives that can improve certain performance characteristics of the battery, such as additives that improve the overcharge performance of the battery, or additives that improve the high-temperature or low-temperature performance of the battery.

[0111] The features and advantages described above for the positive electrode plate also apply to this solid-state battery and will not be repeated here.

[0112] In a fifth aspect of the present application, the present application proposes an electrical device. According to an embodiment of the present application, the electrical device includes the battery described above. According to an embodiment of the present application, the electrical device may include, but is not limited to, a mobile phone, a laptop computer, an electric vehicle, and the like.

[0113] The features and advantages described above for the battery also apply to the electrical equipment in question and will not be repeated here.

[0114] Examples of the present application are described below. The examples described below are illustrative and are used solely to illustrate the present application and should not be considered limiting. Where the examples do not specify any particular technique or conditions, they should be carried out in accordance with the technique or conditions described in the art literature or in accordance with the product specification. Where the manufacturer of the reagents or equipment used is not indicated, they are conventional products available on the market.

[0115] Example 1 (1) Nickel sulfate, cobalt sulfate, and manganese sulfate are dissolved in pure water in a molar ratio of nickel, cobalt, and manganese of 84:10:6 to obtain a mixed salt solution with a concentration of 2 mol / L. A sodium hydroxide solution with a concentration of 8 mol / L is prepared as a precipitating agent solution. A 6 mol / L aqueous ammonia solution is prepared as a complexing agent solution. Nitrogen gas is supplied to the reaction vessel for protection, and the temperature of the reaction system is controlled to 60°C. The mixed salt solution, sodium hydroxide solution, and aqueous ammonia are added to the reaction vessel from the liquid supply pipes, respectively. The stirring speed is maintained at 500 rpm, and the supply rate of the mixed salt solution is controlled to 500 mL / h. The ammonia content in the coprecipitation reaction system is controlled to 4.5 g / L. The mixture is aged for 1 hour, then separated, washed, and dried to obtain a cathode active material precursor. (2) The above precursor, lithium hydroxide, tin oxide, and ammonium dihydrogen phosphate were weighed according to the sum of nickel-cobalt-manganese elements in the precursor, and the molar ratio of lithium, tin, and phosphorus elements of 1:1.03:0.004:0.003, respectively, and then uniformly mixed in a mixer. The mixture was then sintered at a constant temperature in an oxygen furnace, with the oxygen concentration in the oxygen-containing gas in the oxygen furnace being greater than 95% by volume, the heating rate being 5°C / min, the sintering temperature being 810°C, and the sintering time being 10h. After natural cooling to room temperature, the mixture was crushed, sieved, and iron removed to obtain the positive electrode active material - calcined material. (3) The positive electrode active material - calcined material and boric acid are uniformly mixed in a high-speed mixer with a molar ratio of the sum of transition metal elements in the positive electrode active material - calcined material to boron elements of 1:0.001, and sintered at a constant temperature of 350°C in an oxygen furnace, with the oxygen concentration in the oxygen-containing gas in the oxygen furnace being greater than 90% by volume, and the sintering time being 10 hours. After cooling, sieving, and iron removal, the positive electrode active material Li 1.03 Ni 0.813 Co 0.100 Mn 0.060 Nb 0.004 P 0.003 O2@B is obtained, and in the positive electrode active material chemical formula, the part before @ is the substrate component, and the part after @ is the main element in the coating layer.

[0116] Examples 2-8 and Comparative Examples 1-4 The positive electrode active material was manufactured according to the method of Example 1, and the material composition and specific process conditions are shown in Table 1.

[0117] In Example 2, ditungsten trioxide and ammonium dihydrogen phosphate were used as the dopant, and boric acid was used as the coating agent.

[0118] In Example 3, divanadium trioxide and ammonium dihydrogen phosphate were used as the dopant, and boric acid was used as the coating agent.

[0119] In Example 4, molybdenum oxide and boric acid were used as the dopant, and tungsten trioxide was used as the coating agent.

[0120] In Example 5, tin oxide and boric acid were used as the dopant, and tungsten trioxide was used as the coating agent.

[0121] In Example 6, boric acid was used as the dopant and as the coating agent.

[0122] In Example 7, diniobium pentoxide and boric acid were used as the dopant, and boric acid was used as the coating agent.

[0123] In Example 8, tin oxide and ammonium dihydrogen phosphate were used as the dopant, and no coating agent was used.

[0124] In Comparative Example 1, aluminum trioxide was used as the dopant and boric acid was used as the coating agent.

[0125] In Comparative Example 2, boric acid and ammonium dihydrogen phosphate were used as the dopant, and no coating agent was used.

[0126] In Comparative Example 3, diniobium pentoxide and ammonium dihydrogen phosphate were used as the dopant, and boric acid was used as the coating agent.

[0127] In Comparative Example 4, diniobium pentoxide and ammonium dihydrogen phosphate were used as the dopant, and boric acid was used as the coating agent.

[0128] [Table 1] JPEG2026521086000013.jpg152170

[0129] Table 2 shows the compositions of the precursors R(101) / R(001) and I(101) / I(001) and the positive electrode active material obtained in Example 2-8 and Comparative Example 1-4.

[0130] [Table 2] JPEG2026521086000015.jpg148170

[0131] In the positive electrode active material microcrystals obtained in Examples 2-8 and Comparative Examples 1-4, the average thickness A perpendicular to the direction of the (003) crystal plane is (003) , the spacing B of the (003) crystal planes in the positive electrode active material microcrystals (003) , the average thickness A perpendicular to the direction of the (104) crystal plane in the positive electrode active material microcrystal. (104) , the spacing B of the (104) crystal planes in the positive electrode active material microcrystals (104) , Number of equivalent sheet layers of the positive electrode active material crystal plane R (003) and the equivalent number of (10⁴) crystal plane sheets R of the positive electrode active material (104) and R(104) / R (003) This is shown in Table 3.

[0132] [Table 3]

[0133] The positive electrode active materials obtained in Examples 1-8 and Comparative Examples 1-4 were assembled into 2025 type button batteries, and the initial Coulomb efficiency, cycle performance, rate performance, and lithium-ion diffusion coefficient of the batteries were characterized. The characterization results are shown in Table 4.

[0134] The manufacturing process for the 2025 type button cell battery is as follows: Manufacturing of positive electrode plates: The positive electrode active material, acetylene black, and polyvinylidene fluoride (PVDF) are thoroughly mixed with an appropriate amount of N-methylpyrrolidone (NMP) in a mass ratio of 95:3:2 to form a uniform slurry. The slurry is applied to both surfaces of aluminum foil and dried at 120°C for 12 hours. After that, it is press-molded at a pressure of 100 MPa to produce a positive electrode plate with a diameter of 12 mm and a thickness of 120 μm. Here, the loading of the positive electrode active material on the aluminum foil is 15-16 mg / cm³. 2 And, Battery assembly: The positive electrode plate, separator, negative electrode plate, and electrolyte were assembled into a 2025 type button cell in a glove box filled with argon gas containing less than 5 ppm of both moisture and oxygen, and then allowed to stand for 6 hours. In this process, a metallic lithium sheet with a diameter of 17 mm and a thickness of 1 mm was used for the negative electrode plate, and a polyethylene porous membrane (Celgard 2325) with a thickness of 25 μm was used for the separator. The electrolyte contained lithium salt LiPF6 and a solvent (ethylene carbonate (EC) and diethyl carbonate (DEC) in a volume ratio of 1:1), and the LiPF6 concentration in the electrolyte was 1 mol / L.

[0135] Initial measurement of Coulomb efficiency: At 25°C, the battery is charged to 4.4V with a constant current of 0.1C, then further charged to 0.02C with a constant voltage to obtain the initial charge ratio capacity C0 of the battery, and then discharged to 3.0V with a constant current of 0.1C to obtain the initial discharge ratio capacity C1 of the battery. The initial Coulomb efficiency of the battery is C1 / C0 × 100%. The charge and discharge voltage range was controlled to 3.0-4.3V, and button-type batteries were charged and discharged at room temperature at 0.1C to evaluate the electrochemical performance of the multi-component cathode material.

[0136] Cycle performance measurement: At 45°C, the battery was charged to 4.3V with a constant current of 1C to obtain the initial charge ratio capacity C2 of the battery, then discharged to 3.0V with a constant current of 1C, and then subjected to 80 cycles of constant current charge and discharge with a current of 1C to obtain the discharge ratio capacity C at the 80th cycle. 80 The initial Coulomb efficiency of the battery = C 80 / C2 × 100%.

[0137] Measurement of Rate Performance: The charge / discharge voltage range is controlled to 3.0-4.3V. At room temperature, the button cell battery is charged and discharged for two cycles at 0.1C, then charged and discharged for one cycle each at 0.2C, 0.33C, 0.5C, and 1C. The rate performance of the battery is characterized by the ratio of the initial discharge ratio capacity at 0.1C to the discharge ratio capacity at 1C. Here, the initial discharge ratio capacity at 0.1C is the discharge ratio capacity of the button cell battery after the first cycle, and the discharge ratio capacity at 1C is the discharge ratio capacity of the button cell battery after the sixth cycle.

[0138] Measurement of diffusion coefficient: EIS measurement and analysis were employed. The battery was charged with a constant current of 0.1C to 4.3V, charged at a constant voltage for 30 minutes, discharged to 3.0V with a constant current of 0.1C, and then charged to 4.3V with a constant current of 0.1C. A fully charged half-cell was taken, and EIS measurement was performed in the frequency range of (100)kHz~0.01Hz, with an amplitude of 10mV. According to the following formula, Z re and ω -1 / 2 The slope σ of the fitting line can be determined, Z re =R s +R ct +σω -1 / 2 ω = 2πf Here, Z re R is the real part of the measured impedance spectrum. s is the solution resistance, and R ct ω is the charge transfer resistance, ω is the angular frequency, f is the measurement frequency, and σ is the Warburg factor. Furthermore, the lithium ion diffusion coefficient calculation formula is used to determine the material bulk phase Li + Diffusion coefficient D Li + , D Li + =R 2 T 2 / (2A 2 n 4 F 4 C 2 σ 2 ) seek, Here, R is the ideal gas constant, T is the absolute temperature, A is the electrode cross-sectional area, n is the electron transfer rate, F is the Faraday constant, and C is the lithium ion concentration in the electrode.

[0139] [Table 4]

[0140] As can be seen from Table 3, the R of the positive electrode active material in Examples 1-8 (104) / R (003) The ratio is 1.4-1.8, and the positive electrode active material R in Comparative Examples 1-4 (104) / R (003) None of these are in the 1.4-1.8 range, and as can be seen from Table 4, the initial Coulomb efficiency, rate performance, and capacity retention rate of the batteries in Examples 1-8 are significantly higher than those of the batteries in Comparative Examples 1-4. At the same time, the charge ratio capacity, discharge ratio capacity, and lithium-ion diffusion coefficient are also maintained within an appropriate range, thereby R (104) / R (003) By employing a positive electrode active material with a coefficient of 1.4-1.8, it is demonstrated that the rate performance and cycle performance of the battery carrying it are superior without sacrificing capacity, initial efficiency, and lithium-ion diffusion coefficient.

[0141] In this specification, any reference to terms such as “one embodiment,” “several embodiments,” “example,” “specific example,” or “several examples” means that the particular features, structures, materials, or properties described with reference to such embodiment or example are included in at least one embodiment or example of this application. In this specification, the general expressions of the above terms do not necessarily apply to the same embodiment or example. In addition, the particular features, structures, materials, or properties described may be incorporated in an appropriate manner in any one or more embodiments or examples. Furthermore, those skilled in the art can combine and combine the various embodiments or examples and the features relating to the various embodiments or examples described herein without contradiction.

[0142] Although embodiments of this application have been presented and described, these embodiments are illustrative and should not be understood as limiting this application. Those skilled in the art will understand that various changes, modifications, substitutions, and variations are possible within the scope of this application. (See related applications for cross-references.)

[0143] This application claims priority to the Chinese patent application filed with the China National Intellectual Property Administration on April 30, 2024, with patent application number 202410544723.1 and title "Positive electrode active material and method for manufacturing the same, positive electrode plate, battery and electrical equipment," the entire contents of which are incorporated herein by reference.

Claims

1. A positive electrode active material, wherein the positive electrode active material is a secondary particle. (003) Number of equivalent crystal plane sheets R of the positive electrode active material （００３） (104) Number of equivalent crystal plane sheets R （１０４） R （１０４） / R （００３） The values ​​are 1.4 to 1.

8. [Math 11] Satisfying the condition, A （００３） This is the average thickness perpendicular to the direction of the (003) crystal plane in the positive electrode active material microcrystal, and its unit is nm. B （００３） is the spacing between the (003) crystal planes in the positive electrode active material microcrystal, and its unit is nm. A （１０４） This is the average thickness perpendicular to the direction of the (104) crystal plane in the positive electrode active material microcrystal, and its unit is nm. B （１０４） is the spacing between (104) crystal planes in the positive electrode active material microcrystal, and its unit is nm. Cathode active material.

2. R （１０４） / R （００３） is 1.55 to 1.75 The positive electrode active material according to claim 1.

3. (003) Number of equivalent crystal plane sheets R of the positive electrode active material （００３） The range is 80-130. The positive electrode active material according to claim 1 or 2.

4. (003) Number of equivalent crystal plane sheets R of the positive electrode active material （００３） The range is 90-120. The positive electrode active material according to any one of claims 1 to 3.

5. The number of equivalent sheet layers R of the (104) crystal plane of the positive electrode active material （１０４） The range is 140-210. The positive electrode active material according to any one of claims 1 to 4.

6. The number of equivalent sheet layers R of the (104) crystal plane of the positive electrode active material （１０４） The range is 150-200. The positive electrode active material according to any one of claims 1 to 5.

7. (003) The average thickness A perpendicular to the direction of the crystal plane in the positive electrode active material microcrystal. （００３） The range is 35 nm to 55 nm. The positive electrode active material according to any one of claims 1 to 6.

8. (003) The average thickness A perpendicular to the direction of the crystal plane in the positive electrode active material microcrystal. （００３） The wavelength range is 40 nm to 55 nm. The positive electrode active material according to any one of claims 1 to 7.

9. The spacing B between the crystal planes of the positive electrode active material (003) （００３） The range is 0.4730 nm to 0.4760 nm. The positive electrode active material according to any one of claims 1 to 8.

10. The spacing B between the crystal planes of the positive electrode active material (003) （００３） The range is 0.4735 nm to 0.4750 nm. The positive electrode active material according to any one of claims 1 to 9.

11. The average thickness A perpendicular to the direction of the (104) crystal plane in the positive electrode active material microcrystal. （１０４） The range is 25 nm to 55 nm. The positive electrode active material according to any one of claims 1 to 10.

12. The average thickness A perpendicular to the direction of the (104) crystal plane in the positive electrode active material microcrystal. （１０４） The wavelength is 30 nm to 50 nm. The positive electrode active material according to any one of claims 1 to 11.

13. The spacing B of the (104) crystal planes of the positive electrode active material （１０４） The wavelength is 0.2030 nm to 0.2040 nm. The positive electrode active material according to any one of claims 1 to 12.

14. The spacing B of the (104) crystal planes of the positive electrode active material （１０４） The wavelength range is 0.2035 nm to 0.2040 nm. The positive electrode active material according to any one of claims 1 to 13.

15. The aspect ratio of the primary particles of the positive electrode active material is 2 to 5:

1. The positive electrode active material according to any one of claims 1 to 14.

16. The aspect ratio of the primary particles of the positive electrode active material is 2 to 4:

1. The positive electrode active material according to any one of claims 1 to 15.

17. The cross-sectional porosity of the positive electrode active material is 2% to 10%. The positive electrode active material according to any one of claims 1 to 16.

18. The cross-sectional porosity of the positive electrode active material is 3% to 8%. The positive electrode active material according to any one of claims 1 to 17.

19. The BET specific surface area of ​​the positive electrode active material is 0.4 m². ２ / g to 0.9m ２ / g The positive electrode active material according to any one of claims 1 to 18.

20. The BET specific surface area of ​​the positive electrode active material is 0.5 m². ２ / g to 0.8m ２ / g The positive electrode active material according to any one of claims 1 to 19.

21. The positive electrode active material includes a substrate, The substrate is Li １＋ａ Ni ｘ Co ｙ Mn ｚ M ｍ O ２ Includes, -0.05 ≤ a ≤ 0.3, 0.8 ≤ x ≤ 1, 0 ≤ y ≤ 0.2, 0 ≤ z ≤ 0.2, 0.002 ≤ m ≤ 0.01, M includes at least one of Sn, W, V, Mo, P, and B. The positive electrode active material according to any one of claims 1 to 20.

22. The aforementioned M further includes at least one of Sb, Nb, Mg, La, Ti, Al, Sr, Ba, Y, Zr, Ca, Fe, S, Zn, and Ta. The positive electrode active material according to claim 21.

23. The positive electrode active material further includes a coating layer formed on at least a portion of the surface of the substrate, The aforementioned coating layer contains element J, The aforementioned element J includes at least one of Al, Zr, Ti, F, B, Cl, Br, I, S, W, Co, Sn, and Mo. The positive electrode active material according to claim 21 or 22.

24. A method for producing a positive electrode active material according to any one of claims 1 to 23, A step of providing a cathode active material precursor, The first step is to mix and sinter the positive electrode active material precursor, a lithium source, and a dopant containing element M to obtain a positive electrode active material-fired material. A method that includes this.

25. The positive electrode active material precursor is produced by mixing a nickel salt, a cobalt salt, a manganese salt, a precipitating agent, and a complexing agent and allowing them to co-precipitate to obtain the positive electrode active material precursor. The temperature for the aforementioned coprecipitation reaction is 50°C to 80°C. The ammonia content in the aforementioned coprecipitation reaction process is 2 g / L to 8 g / L. The method according to claim 24.

26. The temperature for the coprecipitation reaction is 55°C to 75°C. The ammonia content in the aforementioned coprecipitation reaction process is 3 g / L to 7 g / L. The method according to claim 25.

27. The positive electrode active material precursor is The Dv50 of the positive electrode active material precursor is 9 μm to 20 μm. The number of equivalent sheet layers R of the (101) crystal plane of the positive electrode active material precursor. （１０１） and the (001) equivalent number of crystal plane sheets R of the positive electrode active material precursor （００１） R （１０１） / R （００１） It must satisfy the condition that it is between 2.0 and 3.

0. The peak intensity ratio I of the positive electrode active material precursor （１０１） / I （００１） The value should be between 0.7 and 1.

4. at least one of the following The method according to any one of claims 24 to 26.

28. The peak intensity ratio I of the positive electrode active material precursor （１０１） / I （００１） The range is 0.8 to 1.

2. The method according to claim 27.

29. The temperature for the first mixed sintering is 650°C to 900°C, and the time is 4 hours to 15 hours. The method according to any one of claims 24 to 28.

30. The positive electrode active material - calcined material and the element J-containing coating agent are mixed and sintered in a second manner. The step further includes forming an element J-containing coating layer on at least a portion of the surface of the positive electrode active material-fired material. The method according to any one of claims 24 to 29.

31. The temperature for the second mixed sintering is 200°C to 700°C, and the time is 3 hours to 10 hours. The method according to claim 30.

32. The positive electrode active material includes the positive electrode active material described in any one of claims 1 to 23 or the positive electrode active material obtained by the method described in any one of claims 24 to 31. Positive electrode plate.

33. Includes the positive electrode plate described in claim 32 battery.

34. Includes the battery described in claim 33 Electrical equipment.

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