Positive electrode material, positive electrode sheet, secondary battery and power-consuming device

Abstract

Positive electrode material, characterized in that the positive electrode material comprises a positive electrode material particle, wherein the positive electrode material particle comprises a substrate and a modifying element, wherein: the substrate LiNi x Co y Mn z O2 contains, where x ≥ 0.8, y ≤ 0.12 and x + y + z = 1; and the modifying element comprises a rare earth element and / or a high-melting-point metallic element.

Description

Technical field

[0001] The present application relates to the field of batteries, in particular a positive electrode material, a positive electrode sheet, a secondary battery and a power-consuming device. State of the art

[0002] With the advent of CO2 neutrality targets, the development of readily available and cost-effective positive electrode materials for high-energy-density batteries remains a significant challenge to meet the ever-increasing range demands of power-consuming devices such as long-range electric vehicles. High-nickel layered materials offer advantages such as high capacity and low cost and are considered one of the most promising positive electrode materials for lithium-ion batteries. However, the widely used high-nickel polycrystalline positive electrodes currently exhibit poor cycle stability at deep charge and discharge rates, severely limiting their commercial application. General information about the invention; Technical problems

[0003] The present application relates to a positive electrode material, a positive electrode sheet, a secondary battery and a power-consuming device with which the cycle stability of the positive electrode material can be improved. Problem solving Technical solutions

[0004] In a first aspect, the present application proposes a positive electrode material comprising a positive electrode material particle, wherein the positive electrode material particle comprises a substrate and a modifying element, wherein the substrate comprises a LiNixCoyMnzO2, where x ≥ 0.8, y ≤ 0.12 and x + y + z = 1; the modifying element comprises a rare earth element and / or a high-melting-point metallic element.

[0005] In the technical solution of the embodiments of the present application, the rare-earth element and / or the high-melting-point metal element is used to modify ternary particles with a high nickel content. Rare-earth metal atoms (hereinafter referred to as element A) can penetrate the surface structure of the positive electrode material and form an A-rich network of fast ionic conductors on the surface of the ternary particles with a high nickel content. This isolates the electrolyte solution, reduces side reactions, and thereby improves cycle performance. The high-melting-point metal element (hereinafter referred to as element B) can penetrate the bulk phase of the positive electrode with a high nickel content and form a stable structure with strong binding energy. This reduces the formation of impurities such as the rock salt phase under high voltage and thereby improves cycle performance.Consequently, by modifying ternary particles with a high nickel content with the rare earth element and / or the high-melting-point metal element, the cycle stability of the positive electrode material can be improved.

[0006] In some embodiments, the rare-earth element is located at least partially on the surface of the substrate. When modifying high-nickel ternary particles using the rare-earth element, rare-earth metal atoms (hereinafter referred to as element A) can at least partially penetrate the surface structure of the positive electrode material. This creates an A-rich network of fast ionic conductors on the surface of the high-nickel ternary particles. This isolates the electrolyte solution, reduces side reactions, and thus improves cycle performance.

[0007] In some embodiments, the high-melting-point metal element is located at least partially within the substrate. When modifying ternary particles with a high nickel content using the high-melting-point metal element, at least a portion of the element penetrates the bulk phase of the high-nickel positive electrode and forms a stable structure with strong binding energy. This reduces the formation of impurities such as the rock salt phase under high voltage and thereby improves cycle performance.

[0008] In some embodiments, the rare-earth element comprises at least one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. Modifying high-nickel ternary particles with the rare-earth element significantly improves the cycle performance of the high-nickel ternary particles when used as the positive electrode material.

[0009] In some embodiments, the rare earth element is lanthanum. Modifying high-nickel ternary particles using lanthanum significantly improves the cycle performance of the high-nickel ternary particles when used as the positive electrode material, while the modification process is easily achievable.

[0010] In some embodiments, the high-melting-point metal element comprises at least one of the elements titanium, zirconium, niobium, vanadium, molybdenum, and tungsten. Modifying high-nickel ternary particles with the high-melting-point metal element significantly improves the cycle performance of the high-nickel ternary particles when used as the positive electrode material.

[0011] In some embodiments, the high-melting-point metal element is niobium. Modifying high-nickel ternary particles using niobium significantly improves the cycle performance of the high-nickel ternary particles when used as the positive electrode material, while the modification process is easily achievable.

[0012] In some embodiments, the modifying element is introduced into the substrate by doping. Introducing the modifying element into the substrate by doping improves the bonding effectiveness between the modifying element and the substrate, thereby reducing the probability of the modifying element detaching from the substrate and ensuring the modifying effect on the ternary particles with a high nickel content.

[0013] In some embodiments, the doping mass of the modifying element is 1 to 10% of the mass of the positive electrode material. By controlling the doping mass of the modifying element in the range of 1 to 10%, excellent modification effects for ternary particles with high nickel content can be achieved, and costs can be better controlled.

[0014] In some embodiments, the doping mass of the modifying element is 3 to 5% of the mass of the positive electrode material (100%). Controlling the doping mass of the modifying element within this range results in a more pronounced modification effect for ternary particles with a high nickel content.

[0015] In some embodiments, the LiNixCoyMnzO2 is a single-crystal particle. The selection of single-crystal ternary particles with a high nickel content, with their pore-free and high-strength properties, contributes to improving the compaction density of the positive electrode material and thus increasing the energy density of the battery. Simultaneously, this enables improved structural stability and cycle life of the positive electrode material with superior stability under high voltage.

[0016] In some embodiments, the Dv50 value of LiNixCoyMnzO2 is ≥ 4 µm. By specifying that the Dv50 value of the high-nickel ternary particles is ≥ 4 µm, the particle fragmentation rate during the cycle process can be reduced. This allows for improved compaction density, resulting in a positive electrode material with enhanced structural stability and cycle performance.

[0017] In some embodiments, the SPAN value of LiNiXCoyMnzO2 is ≥ 1.6. By specifying that the SPAN value of the high-nickel ternary particles is ≥ 1.6, the particle fragmentation rate during the cycle process can be reduced. This allows for improved compaction density, resulting in a positive electrode material with enhanced structural stability and cycle performance.

[0018] In one example, the present application describes a manufacturing process for a positive electrode material, comprising a subsequent step wherein a modifier is mixed with the LiNixCoyMnzO2 and the positive electrode material is produced by calcination, whereby In LiNixCoyMnzO2, x ≥ 0.8, y ≤ 0.12 and x + y + z = 1, the following holds: where the modifier comprises a rare earth element and / or a high-melting-point metallic element.

[0019] In the technical solution of the embodiments of the present application, ternary particles with a high nickel content can be produced by mixing or calcining LiNixCoyMnzO2 with the modifier containing the rare earth element and / or the high-melting-point metal element. This effectively improves the structural stability and cycle performance of the ternary particles with a high nickel content when used as the positive electrode material of the battery.

[0020] In some embodiments, the modifier comprises LiXAYBZO(X+3Y+5Z) / 2, LiXAYO(X+3Y) / 2 or LiXBZO(X+5Z) / 2, where X ≥ 5, Y ≥ 3, Z ≥ 2 and A is one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium, and B is one of the elements titanium, zirconium, niobium, vanadium, molybdenum and tungsten.

[0021] By using LiXAYBZO(X+3Y+5Z) / 2, LiaAbO(a+3b) / 2, or LiaBcO(a+5c) / 2 as the modifier and mixing or calcining it with LiNixCoyMnzO2, one obtains ternary particles with a high nickel content, modified with the rare earth element and the high-melting-point metal element, modified with the rare earth element, and modified with the high-melting-point metal element. All three approaches effectively improve the structural stability and cycle performance of the ternary particles with a high nickel content when used as the positive electrode material of the battery.

[0022] In some embodiments, the calcination temperature is 600 to 800 °C and the calcination time is 1 to 3 hours. Under these calcination conditions, the manufacturing efficiency of the positive electrode material is high.

[0023] In a second aspect, the present application proposes a positive electrode sheet comprising the positive electrode material described in the aforementioned embodiments or the positive electrode material produced according to the aforementioned embodiments.

[0024] In a third aspect, the present application proposes a secondary battery comprising the positive electrode sheet described in the aforementioned embodiments.

[0025] In a fourth aspect, the present application proposes a power-consuming device comprising the secondary battery described in the aforementioned embodiments. Advantageous effects of the invention

[0026] In the technical solution of the embodiments of the present application, the rare-earth element and / or the high-melting-point metal element is used to modify ternary particles with a high nickel content. Rare-earth metal atoms (hereinafter referred to as element A) can penetrate the surface structure of the positive electrode material and form an A-rich network of fast ionic conductors on the surface of the ternary particles with a high nickel content. This isolates the electrolyte solution, reduces side reactions, and thereby improves cycle performance. The high-melting-point metal element (hereinafter referred to as element B) can penetrate the bulk phase of the positive electrode with a high nickel content and form a stable structure with strong binding energy. This reduces the formation of impurities such as the rock salt phase under high voltage and thereby improves cycle performance.Consequently, by modifying ternary particles with a high nickel content with the rare earth element and / or the high-melting-point metal element, the cycle stability of the positive electrode material can be improved. Brief description of the attached drawings

[0027] To more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, a brief introduction to the drawings necessary for describing the embodiments or the prior art is given below. It is obvious that the drawings described below represent only some embodiments of the present application. A person skilled in the art can derive further relevant drawings from these drawings without any creative effort. Fig.Figure 1 is a schematic representation illustrating the structure of some embodiments of the positive electrode material provided in the present application.

[0028] The objectives, functional features and advantages of the present application are explained in more detail with reference to the attached drawings and in conjunction with the exemplary embodiments. Exemplary embodiments of the invention

[0029] The following section, with reference to the accompanying drawings, describes in detail embodiments of the positive electrode material and its manufacturing process, the positive electrode sheet, the secondary battery, the battery module, the battery pack, and the current-consuming device, each disclosed in the present application. Unnecessary details may be omitted. For example, a detailed description of known facts and a repeated description of essentially the same structure may be avoided. This is to prevent the following description from becoming unnecessarily long and to facilitate understanding by the person skilled in the art. Furthermore, the drawings and the following description serve to provide the person skilled in the art with a complete understanding of the present application and are not intended to limit the subject matter described in the claims.

[0030] The “ranges” disclosed in this application are defined in the form of lower and upper limits. A specific range is defined by selecting a lower and an upper limit. The selected lower and upper limits define the boundaries of the respective range. The range thus defined can include or exclude the end values ​​and can be combined arbitrarily; that is, any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60 to 120 and 80 to 110 are listed for a particular parameter, it is understood that ranges of 60 to 110 and 80 to 120 are also considered. Furthermore, if minimum range values ​​of 1 and 2 and maximum range values ​​of 3, 4, and 5 are listed, all of the following ranges are considered: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, and 2 to 5.In this application, unless otherwise specified, a range of numbers “a to b” represents an abbreviation for any combination of real numbers between a and b, where a and b are both real numbers. For example, the range of numbers “0 to 5” means that all real numbers between “0 and 5” have been listed in this article, and “0 to 5” is simply an abbreviation for these combinations of numbers. Furthermore, when a parameter is expressed as an integer ≥ 2, this is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0031] Unless otherwise stated, all embodiments and optional embodiments of the present application may be combined to form a new technical solution.

[0032] Unless otherwise stated, all technical features and optional technical features of the present application may be combined to form a new technical solution.

[0033] Unless otherwise stated, all steps of the present application may be carried out successively or in any order, but preferably consecutively. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) carried out consecutively, or that the method may include steps (b) and (a) carried out consecutively. For example, this means that the method may also include step (c), that step (c) may be added in any order, and the method may, for example, include steps (a), (b) and (c), or steps (a), (c) and (b), or steps (c), (a) and (b), etc.

[0034] Unless otherwise stated, the terms "include" and "contain" mentioned in this application may be open or closed. For example, "include" and "contain" may mean that other, unlisted components may also be included or contained, or that only the listed components are included or contained.

[0035] Unless expressly stated otherwise, the term "or" in this application is inclusive. For example, the expression "A or B" means "A, B, or both A and B." More precisely, the condition "A or B" is satisfied if any of the following conditions are true: A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0036] Current market developments indicate that the use of high-performance batteries is becoming increasingly widespread. High-performance batteries are not only used in energy storage and power supply systems such as hydroelectric, thermal, wind, and solar power plants, but also find broad application in electric transport vehicles like e-bikes, e-motorcycles, and electric cars, as well as in military equipment, aerospace, and other sectors. As the application areas of high-performance batteries continue to expand, market demand is also constantly increasing.

[0037] With the advent of carbon neutrality targets, the development of readily available and cost-effective positive electrode materials for high-energy-density batteries remains a significant challenge to meet the ever-increasing range demands of power-consuming devices such as long-range electric vehicles. High-nickel layered materials offer advantages such as high capacity and low cost and are considered one of the most promising positive electrode materials for lithium-ion batteries. However, the widely used high-nickel polycrystalline positive electrodes currently exhibit poor cycle stability at deep charge and discharge rates, severely limiting their commercial application.

[0038] Based on the above considerations, the inventor, in order to solve the problem of the poor cycle performance of high-nickel positive electrode materials, which limits their practical application, has developed a modification process for high-nickel positive electrode materials through in-depth research. This process improves the cycle performance of the high-nickel positive electrode materials through ion doping.

[0039] In particular, in some embodiments of the present application, the positive electrode material comprises a positive electrode material particle, wherein the positive electrode material particle comprises a substrate and a modifying element, wherein: the substrate comprises LiNixCoyMnzO2, wherein x ≥ 0.8, y ≤ 0.12 and x + y + z = 1, while the modifying element comprises a rare earth element and / or a high-melting-point metal element.

[0040] In the technical solution of the embodiments of the present application, the rare-earth element and / or the high-melting-point metal element are used to modify ternary particles with a high nickel content. The rare-earth element (hereinafter referred to as element A) can penetrate the surface structure of the positive electrode and form a nickel-rich network of fast ionic conductors. This isolates the electrolyte solution, reduces side reactions, and thereby improves cycle performance. The high-melting-point metal element (hereinafter referred to as element B) can penetrate the bulk phase of the high-nickel positive electrode and form a stable structure with strong binding energy. This reduces the formation of impurities such as the rock salt phase under high voltage and thereby improves cycle performance.Consequently, modifying high-nickel ternary particles with the rare-earth element and / or the high-melting-point metal element can improve the cycle stability of the positive electrode material. Furthermore, when both the rare-earth element and the high-melting-point metal element are used to modify high-nickel ternary particles, relevant performance tests show superior results compared to modifications using either only the rare-earth element or only the high-melting-point metal element. This superiority is particularly evident in improved cycle life and storage life.

[0041] Rare earth elements are a collective term for the lanthanide series (La) together with scandium (Sc) and yttrium (Y), a total of 17 elements. The lanthanide series specifically refers to the 15 elements from lanthanum (element 57) to lutetium (element 71) in the periodic table. Theoretically, all rare earth elements can effectively modify the high-nickel ternary particles described in the present application. In some embodiments of the present application, the rare earth element is a lanthanide element and comprises, in particular, at least one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. The modification of high-nickel ternary particles with the rare earth element significantly improves the cycle performance of the high-nickel ternary particles when used as the positive electrode material.

[0042] In some embodiments of the present application, the rare earth element is lanthanum. The modification of high-nickel ternary particles using lanthanum significantly improves the cycle performance of the high-nickel ternary particles when used as the positive electrode material, while the modification process is easily executable.

[0043] Typical high-melting-point metals are tungsten, tantalum, molybdenum, niobium, hafnium, chromium, vanadium, zirconium, and titanium. Theoretically, all of these metallic elements can effectively modify the high-nickel ternary particles described in the present application. In some embodiments of the present application, the high-melting-point metal element comprises at least one of the elements titanium, zirconium, niobium, vanadium, molybdenum, and tungsten. Modifying high-nickel ternary particles with the high-melting-point metal element significantly improves the cycle performance of the high-nickel ternary particles when used as the positive electrode material.

[0044] In some embodiments of the present application, the high-melting-point metal element is niobium. Modifying high-nickel ternary particles using niobium significantly improves the cycle performance of the high-nickel ternary particles when used as the positive electrode material, while the modification process is easily achievable.

[0045] In some embodiments of the present application, the rare-earth element is located at least partially on the surface of the substrate. When modifying ternary particles with a high nickel content using the rare-earth element, rare-earth metal atoms can penetrate at least partially into the surface structure of the positive electrode material. This creates an alpha-rich network of fast ionic conductors on the surface of the ternary particles with a high nickel content. This isolates the electrolyte solution, reduces side reactions, and thereby improves cycle performance.

[0046] In some embodiments of the present application, the high-melting-point metal element is located at least partially within the substrate. When modifying ternary particles with a high nickel content using the high-melting-point metal element, at least a portion of the element penetrates the bulk phase of the high-nickel positive electrode and forms a stable structure with strong binding energy. This reduces the formation of impurities such as the rock salt phase under high voltage and thereby improves cycle performance.

[0047] In some embodiments, the modifying element is introduced into the substrate by doping. Introducing the modifying element into the substrate by doping improves the bonding effectiveness between the modifying element and the substrate, thereby reducing the likelihood of the modifying element detaching from the substrate and ensuring the modifying effect on the ternary particles with a high nickel content. Specifically, the doping method includes surface doping and / or bulk doping. When the rare-earth element is used as the modifying element, surface doping is employed. This is typically done by coating the substrate surface. When the high-melting-point metal element serves as the modifying element, bulk doping is used, which typically penetrates the bulk phase of the substrate.In some embodiments of the present invention, both surface doping and volume doping can be achieved by mixing or calcining the material containing the modifying element together with the substrate.

[0048] In some detailed embodiments of the present application, the modifying element comprises a lanthanide element, wherein the lanthanide element is located at least partially on the surface of the high-nickel ternary particles. This can be considered a modification of the surface layer of the high-nickel ternary particles. The atoms of A penetrate the surface structure of the positive electrode material and form an A-rich network of fast ionic conductors. This isolates the electrolyte solution, reduces side reactions, and thereby improves cycle performance. A method for modifying high-nickel ternary particles using the lanthanide element can, for example, involve mixing or...Calcination of LiXAYO(X+3Y) / 2 (where X ≥ 5, Y ≥ 3, X and Y are integers and A is one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium) with LiNixCoyMnzO2, i.e. ternary particles with a high nickel content.

[0049] In some detailed embodiments of the present application, the modifying element comprises at least one of the elements titanium, zirconium, niobium, vanadium, molybdenum, and tungsten, wherein at least a portion of it is located within the high-nickel ternary particles. This can be considered a modification of the inner layer of the high-nickel ternary particles. The modifying element B thus enters the bulk phase of the high-nickel positive electrode and forms a stable structure with strong binding energy. This reduces the formation of impurities such as the rock salt phase under high voltage and thereby improves cycle performance. A method for modifying high-nickel ternary particles using at least one of the elements titanium, zirconium, niobium, vanadium, molybdenum, and tungsten can, for example, involve mixing or...Calcining of LiXBZO(X+5Z) / 2 ​​(where X ≥ 5, Z ≥ 2, X and Z are integers and B is one of the elements titanium, zirconium, niobium, vanadium, molybdenum and tungsten) with LiNixCoyMnzO2.

[0050] In some embodiments of the present application, with reference to Fig.1. The modifying element comprises a lanthanide element and a high-melting-point metal element. The lanthanide metal is located at least partially on the surface of the high-nickel ternary particles to modify the surface layer of these particles. The atoms of element A penetrate the surface structure of the positive electrode and form an A-rich network of fast ionic conductors. This isolates the electrolyte solution, reduces side reactions, and thereby improves cycle performance. The high-melting-point metal element is located at least partially within the high-nickel ternary particles to modify their inner layer. Modifying element B enters the bulk phase of the high-nickel positive electrode and forms a stable structure with high binding energy.This reduces the formation of impurities such as the rock salt phase under high voltage, thereby improving cycle performance. The combined modifying effects between the lanthanide element and the high-melting-point metal element thus allow for a more stable overall structure of the high-nickel positive electrode material and further enhance cycle performance. A method for modifying ternary particles with a high nickel content using the lanthanide element and the high-melting-point metal element as the modifying element can, for example, be the mixing or calcining of LiXAYBZO(X+3Y+5Z) / 2 ​​(where X ≥ 5, Y ≥ 3, Z ≥ 2 and X, Y, Z are integers and A is one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium and B is one of the elements titanium, zirconium, niobium, vanadium, molybdenum and tungsten) with LiNixCoyMnzO2.

[0051] SEM and EDS analyses of high-nickel ternary particles before and after modification with LiNixCoyMnzO2 revealed that element A was concentrated in the surface layer of high-nickel ternary particles, with relatively low element deposition, while element B was incorporated into the bulk phase of the particles with higher element deposition. This demonstrates that the modification method presented here enables successful modification of the surface layer, the internal layer, or modification with co-doping of both the surface and bulk phases.

[0052] In some embodiments, the doping mass of the modifying element is furthermore 1 to 10% of the mass of the positive electrode material. By controlling the doping mass of the modifying element in the range of 1 to 10%, excellent modification effects for high-nickel ternary particles can be achieved, and costs can be better controlled. It is understood that if the modifying element comprises either element A or element B, the doping quantity of the modifying element refers to the doping quantity of element A or element B among the high-nickel ternary particles. If the modifying element comprises both element A and element B, the doping quantity of the modifying element refers to the total doping quantity of elements A and B.

[0053] In some embodiments, the doping mass of the modifying element is 3 to 5% of the mass of the positive electrode material (100%). Controlling the doping mass of the modifying element within this range results in a more pronounced modification effect for ternary particles with a high nickel content, leading to superior cycle performance.

[0054] In some embodiments of the present application, the LiNixCoyMnzO2 is a single-crystal particle. The selection of single-crystal ternary particles with a high nickel content contributes to improving the density of the high-nickel positive electrode material due to their pore-free and high-strength properties, thereby increasing the battery's energy density. Simultaneously, this enables improved structural stability and cycle life of the high-nickel positive electrode material. Furthermore, single-crystal ternary materials with a high nickel content exhibit excellent high-voltage stability with an upper voltage limit of ≥ 4.3 V. At high voltage (4.3 V), polycrystalline cells with a high nickel content undergo volume reduction due to the irreversible phase transition between H2 and H3 structures, which inevitably leads to the formation of nanocracks in the strong delitiation state.Furthermore, the cathode surface inevitably comes into contact with the electrolyte, leading to strong interfacial reactions. In the present application, ion doping accelerates electron / ion conduction while simultaneously stabilizing the internal lattice structure. The dopant element with strong metal-oxygen bond energies (MO) suppresses the migration of transition metal ions (TM), mitigates structural degradation, and promotes Li+ diffusion. Moreover, the coating layer formed by modification with the rare-earth element in the present application creates a network of fast ion conductors, which can improve low-state-of-charge (SOC) kinetics and enhance the performance of power batteries.

[0055] When using materials with a high nickel content as the positive electrode material of the battery, the particle size of these materials also influences relevant performance characteristics of the battery. Table 1 lists the relevant performance parameters for different particle sizes.

[0056] Table 1 Performance parameters of LiNixCoyMnzO2 with different particle sizes [Table 1] Particle size Dv50 (µm) Energy density 25°C 10% SOCDCR Cycle life at 25°C and 2.8 to 4.3 V Storage at 60 °C and 4.3 V (in days) 3 High High 1200 280 5 Moderately high Moderately high 1500 300 10 Moderate Moderately high 1650 500

[0057] As shown in Table 1, the particle size of LiNixCoyMnzO2 increased, resulting in a slight decrease in energy density. However, the DCR, cycle, and storage performance improved significantly. Furthermore, the large single crystals exhibited lower susceptibility to cracking and excellent high-voltage stability.

[0058] In some embodiments of the present application, the Dv50 value of LiNixCoyMnzO2 is ≥ 4 µm. Here, Dv50 ≥ 4 µm means that 50% of the particles in the volume distribution correspond to a particle size of ≥ 4 µm. By specifying that the Dv50 value of the high-nickel ternary particles is ≥ 4 µm, the compact packing of particles of different sizes prevents excessive local stress accumulation in larger particles, thereby reducing their susceptibility to fragmentation. This approach lowers the fragmentation rate of high-nickel ternary particles during the cycle process, facilitates the achievement of superior compaction density, and ultimately leads to a positive electrode material with improved structural stability and cycle performance.Furthermore, in practical applications, a more specific particle size range can be selected based on Dv50 ≥ 4 µm in conjunction with the specific performance parameters required for the battery.

[0059] In some embodiments of the present application, the SPAN value of LiNixCoyMnzO2 is ≥ 1.6. Here, SPAN = (Dv90 - Dv10) / Dv50, where Dv90 represents the particle size corresponding to 90% of the particle volume distribution, Dv10 the particle size corresponding to 10% of the particle volume distribution, and Dv50 the particle size corresponding to 50% of the particle volume distribution. By specifying that the SPAN value of the ternary particles with a high nickel content is ≥ 1.6, the compact packing of particles of different sizes prevents excessive local stress accumulation in larger particles, thereby reducing their susceptibility to fragmentation. This approach lowers the particle fragmentation rate during the cycle process, facilitates the achievement of superior compaction density, and ultimately leads to a positive electrode material with improved structural stability and cycle performance.

[0060] In one example, the present application describes a manufacturing process for the positive electrode material described in the aforementioned embodiments, wherein the manufacturing process for the positive electrode material particularly comprises a subsequent step, wherein A modifier is mixed with the LiNixCoyMnzO2 and the positive electrode material is produced by calcination, wherein in LiNixCoyMnzO2 x ≥ 0.8, y ≤ 0.12 and x + y + z = 1 and the modifier comprises a rare earth element and / or a high-melting-point metal element.

[0061] In the technical solution of the embodiments of the present application, the rare-earth element and / or the high-melting-point metal element (B) can be introduced into the LiNixCoyMnzO2 by doping through mixing or calcination with the modifier. This produces ternary particles with a high nickel content modified with the rare-earth element and / or the high-melting-point metal element. This effectively improves the structural stability and cycle performance of the ternary particles with a high nickel content when used as the positive electrode material of the battery.

[0062] In some embodiments of the present application, the rare-earth element comprises a lanthanide element, in particular at least one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium. The high-melting-point metal element comprises at least one of titanium, zirconium, niobium, vanadium, molybdenum, and tungsten. Accordingly, the modifier includes LiXAYBZO(X+3Y+5Z) / 2, LiXAYO(X+3Y) / 2 or LiXBZO(X+5Z) / 2, where X ≥ 5, Y ≥ 3, Z ≥ 2 and X, Y, Z are integers and A is one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium and B is one of the elements titanium, zirconium, niobium, vanadium, molybdenum and tungsten.

[0063] By using LiXAYBZO(X+3Y+5Z) / 2, LiaAbO(a+3b) / 2, or LiaBcO(a+5c) / 2 as the modifier and mixing or calcining it with LiNixCoyMnzO2, high-nickel ternary particles are obtained. These particles are modified with the lanthanide element on the surface, with the high-melting-point metal element in the interior, and with the rare-earth element on the surface and simultaneously with the high-melting-point metal element in the interior. All three approaches effectively improve the structural stability and cycle performance of the high-nickel ternary particles when used as the positive electrode material of the battery.

[0064] In some embodiments of the present application, the modifier LiXAYO(X+3Y) / 2 (where X ≥ 5, Y ≥ 3, X and Y are integers, and A is one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium) is mixed with LiNixCoyMnzO2 and calcined to modify the surface layer of the high-nickel material. The atoms of A penetrate the surface structure of the positive electrode material, forming an A-rich network of fast ionic conductors. This isolates the electrolyte solution, reduces side reactions, and thereby improves cycle performance.

[0065] In some embodiments of the present application, the modifier is LiXBZO(X+5Z) / 2 ​​(where X ≥ 5, Z ≥ 2, X and Z are integers, and B is one of the elements titanium, zirconium, niobium, vanadium, molybdenum, and tungsten), which is mixed with LiNixCoyMnzO2 and calcined to modify the inner layer of the high-nickel material. Element B is thereby introduced into the bulk phase of the high-nickel positive electrode and forms a stable structure with strong binding energy. This reduces the formation of impurities such as the rock salt phase under high voltage and thus improves cycle performance.

[0066] In some embodiments of the present application, the modifier LiXAYBZO(X+3Y+5Z) / 2 ​​(where X ≥ 5, Y ≥ 3, Z ≥ 2 and X, Y, Z are integers and A is one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium and B is one of the elements titanium, zirconium, niobium, vanadium, molybdenum and tungsten) is mixed with LiNixCoyMnzO2 and calcined to enable simultaneous modification of the surface layer and the internal layer of the high-nickel material. The co-doping with the metallic lanthanide element and the B element further improves the overall structural stability and cycle stability of the high-nickel material.At the same time, the surface layer A forms a network of fast ion conductors with Li, providing a fast diffusion pathway for lithium ion transport and further improving the battery's performance.

[0067] In some embodiments of the present application, the calcination temperature is 600 to 800 °C and the calcination time is 1 to 3 hours. Under these calcination conditions, the production efficiency of the positive electrode material is high.

[0068] Furthermore, in some embodiments of the present application, a process for the preparation of single-crystal LiNiXCoyMnzO2 is provided, comprising the following steps: First, soluble sulfates of nickel, cobalt, and manganese are prepared in a specific molar ratio of nickel, cobalt, and manganese ions (e.g., 83:12:5) to form a solution with a total molar concentration of metal ions in the range of 1.0 to 2.2 mol / l. Subsequently, sodium hydroxide solution (concentration 4 to 8 mol / l) and ammonia solution (concentration 0.1 to 0.5 mol / l) are added successively and stirred. The solution undergoes a coprecipitation reaction under a nitrogen atmosphere, the pH of the reaction being controlled to 9 to 12 and the reaction temperature to 40 to 60 °C, yielding a hydroxide precursor containing nickel, cobalt, and manganese. The precursor was washed, dried and mixed with the fluxes LiOH and KCl.It was first sintered for 5 to 7 hours at 300 to 500 °C and then calcined for 12 to 18 hours at 700 to 900 °C. Subsequently, a 2 to 4-hour annealing treatment in oxygen at 400 to 600 °C is carried out to obtain a ternary, high-nickel material powder of single-crystal LiNiXCoyMnzO2 (x ≥ 0.8, y ≤ 0.12, x + y + z = 1).

[0069] Furthermore, in some embodiments of the present application, using the modification of LiNixCoyMnzO2 with LiXAYBZO(X+3Y+5Z) / 2 ​​(where X ≥ 5, Y ≥ 3, Z ≥ 2, A is lanthanum and B is niobium), a more detailed fabrication process for the positive electrode material is provided. The individual steps are as follows: LiNO3, La(CH3COO)3, and C4H4NNbO9·nH2O are dissolved in ethanol in stoichiometric ratios as starting materials for the preparation of LiXAYBZO(X+3Y+5Z) / 2. Subsequently, a ternary single-crystal powder is added. The solution is then stirred at 45 to 60 °C until the solvent has completely evaporated. The resulting mixture is then calcined at 600 to 800°C for 1 to 3 hours to obtain the high nickel-modified material with LiXAYBZO(X+3Y+5Z) / 2.

[0070] In a second aspect, the present application proposes a positive electrode sheet comprising the positive electrode material described in the aforementioned embodiments.

[0071] In some embodiments of the present application, the positive electrode sheet comprises a positive electrode current collector and a positive electrode coating applied thereto. The positive electrode coating is formed from a positive electrode paste comprising a positive electrode active substance, a binder, and a conductive material. The binder includes polyvinyl alcohol, carboxymethylcellulose, hydroxypropylcellulose, diacetylcellulose, polyvinyl chloride, polyethylene, polypropylene, styrene-butadiene rubber, acrylated (acrylate-modified) styrene-butadiene rubber, epoxy resin, or nylon, etc. The present application is not subject to any restrictions in this respect. The conductive material includes, among other things, carbon black, acetylene carbon black, Ketjen carbon black, carbon fiber, carbon nanotubes, metal powder, metal fiber, copper, nickel, aluminum, silver, or polyphenylene derivatives, etc.The present application is not subject to any restrictions in this regard.

[0072] In some embodiments of the present application, a manufacturing process for the positive electrode sheet is additionally provided, comprising the following steps: The positive electrode active material (the modified ternary material with a high nickel content provided in the present application), the conductive agent acetylene carbon black, and the binder polyvinylidene fluoride (PVDF) are dissolved in the solvent N-methylpyrrolidone (NMP) in a weight ratio of 96.5:1.5:2. After thorough stirring to achieve uniform mixing, the positive electrode paste is obtained. Subsequently, the positive electrode paste is uniformly applied to the positive electrode current collector, which is coated with a primer. After drying, cold pressing, and cutting, the positive electrode sheet is obtained.

[0073] The positive electrode sheet proposed in the embodiments of the present application exhibits all the advantageous effects of the positive electrode material described in the aforementioned embodiments, which are not listed again here.

[0074] In a third aspect, the present application proposes a secondary battery comprising the positive electrode sheet described in the aforementioned embodiments.

[0075] The secondary battery comprises the positive electrode sheet described in the aforementioned embodiments, as well as a negative electrode sheet, a separator, and an electrolyte solution. The secondary battery can be a battery cell. Using lithium-ion batteries as an example, a lithium-ion battery cell primarily functions through the movement of lithium ions between the positive and negative electrode sheets. In cylindrical battery cells, the three-layer material film structure is wound into a cylindrical electrode arrangement, while in cuboid battery cells, the film structure is either wound or stacked to form an electrode arrangement with an approximately cuboid shape.

[0076] In a typical battery cell structure, the battery cell comprises a casing, an electrode assembly, and an electrolyte solution. The electrode assembly is housed within the battery cell casing and includes a positive electrode sheet, a negative electrode sheet, and a separator. The casing comprises a housing and an end cap. The housing includes a receiving chamber formed by multiple walls and an opening. The end cap is positioned at the opening to seal the receiving chamber. In addition to the electrode assembly, the receiving chamber also contains the electrolyte solution. The positive and negative electrode sheets in the electrode assembly each include an electrode plate. To ensure high current flow without melting, multiple positive electrode plates and multiple negative electrode plates are stacked on top of each other.The electrode tab is electrically connected via a connecting component to an electrode terminal located on the outside of the battery cell. The electrode terminal typically comprises a positive and a negative electrode terminal. In cuboid battery cells, the electrode terminal is usually located at the end cap. Multiple battery cells are connected in series and / or parallel via electrode terminals to enable their use in various applications.

[0077] A battery consisting of cells manufactured using a winding process is called a wound battery. Wound batteries, also known simply as cells, are referred to as wound battery cells in the battery industry. Compared to flat batteries, wound batteries use electrode plates approximately 1 mm thick, which are wound under high pressure.Through special manufacturing techniques, these batteries exhibit several characteristic properties: exceptionally high discharge capacity with a maximum discharge rate of 18C to 30C; excellent performance at high and low temperatures, reliable operation between -55°C and 150°C; stable high output voltage and higher energy density; robust construction with excellent shock resistance; no free electrolyte solution (when using gel acid), allowing operation in any orientation; fast charging capability, achieving over 95% charge within 40 minutes (at a charging rate of 1C); exceptionally long service life with a design life of over 8 years with trickle charging; exceptionally high tolerance to deep discharge at low currents.

[0078] The electrolyte solution used in the present application may be an electrolyte solution known from the prior art and comprising an organic solvent, a lithium salt, and an additive. The separator used in the present application may be a separator known from the prior art.

[0079] The secondary battery proposed in the present application exhibits all the advantageous effects of the aforementioned positive electrode material, which are not listed again here.

[0080] Secondary batteries can be configured as battery modules, formed by electrically connecting a certain number of secondary batteries within a frame to protect the battery cells from external influences such as shocks, heat, vibrations, and similar factors. Common battery modules typically comprise two end plates with multiple battery cells (secondary batteries) positioned between them. An end plate equipped with a battery module output terminal is also referred to as an output terminal end plate, while an end plate without the battery module output terminal is called a non-output terminal end plate.

[0081] Secondary batteries can also be configured as battery packs. In some battery manufacturing processes, several battery cells are first assembled into a battery module. These modules are then encapsulated within a box-like housing to form a battery pack. Within the battery pack, there may be a single row of multiple battery modules or multiple rows of multiple battery modules. The arrangement of multiple rows of battery modules can be two-row with multiple columns, multi-row with multiple columns, multi-row with multiple columns, and so on. For example, in a battery pack with two-row, multi-column battery modules, the first endplate in each column is typically the front output terminal endplate. The two adjacent endplates between the two rows of battery modules serve as the middle non-output terminal endplates. The last endplate in each column functions as the rear non-output terminal endplate.The front output terminal endplate and one of the middle non-output terminal endplates belong to the first row of battery modules, while one middle non-output terminal endplate and the rear non-output terminal endplate belong to the second row of battery modules.

[0082] In a fourth aspect, the present application proposes a power-consuming device comprising the secondary battery described in the aforementioned embodiments.

[0083] The electrically consuming devices covered by this application include, among others: mobile phones, portable devices, laptops, battery-powered vehicles, electric vehicles, ships, spacecraft, electric toys, and power tools. Spacecraft include, for example, airplanes, rockets, space shuttles, and spacecraft, while electric toys can be stationary or mobile, such as game consoles, toy power tools, toy electric boats, and toy electric airplanes. Power tools include electric cutting tools, electric grinding tools, electric assembly tools, and electric railway tools, such as electric drills, electric grinders, electric wrenches, electric screwdrivers, electric hammers, impact drills, concrete vibrators, and electric planers.

[0084] The current-consuming device proposed in the present application exhibits all the advantageous effects of the aforementioned positive electrode material, which are not listed again here.

[0085] The embodiments described below are exemplary and serve only to illustrate the present application; they should not be construed as limiting the present application. If no specific techniques or conditions are indicated in the embodiments, the techniques or conditions described in the technical literature or product instructions should be followed. All reagents and instruments used without manufacturer information are commercially available, conventional products. Example 1 (1) Preparation of single-crystal LiNiXCoYMnzO2: Soluble sulfates of nickel, cobalt, and manganese were prepared in a specific molar ratio of nickel, cobalt, and manganese ions (83:12:5) to form a solution with a total molar concentration of metal ions of 1.5 mol / L. Subsequently, sodium hydroxide solution (concentration 6 mol / L) and ammonia solution (concentration 0.3 mol / L) were added successively and stirred. The coprecipitation reaction was carried out under a nitrogen atmosphere, maintaining a pH of 10 and a reaction temperature of 55 °C to obtain the hydroxide precursor (NiO0.83CoO0.12MnO0.05)(OH)2. The hydroxide precursor was washed, dried, and mixed with the fluxes LiOH and KCl. It was first sintered for 6 hours at 500 °C and then calcined for 15 hours at 800 °C. Finally, it was annealed in oxygen for 3 hours at 600 °C.This resulted in a single-crystal LiNi0,83Co0,12Mn0,05O2 powder from a ternary material with a high nickel content, Dv50 ≥ 4 µm and SPAN ≥ 1.6. (2) Preparation of the modified high-nickel material: LiNO3, La(CH3COO)3, and C4H4NNbO9·nH2O were added to ethanol in stoichiometric ratios as materials for the synthesis of Li5La3Nb2O12, with the addition of a single-crystal ternary powder. The total doping mass of lanthanum and niobium was adjusted to 1%. The solution was then stirred at 55 °C until the solvent had completely evaporated. The resulting mixture was calcined at 700 °C for 3 hours, yielding a 1 wt% modified high-nickel material, namely Li5La3Nb2O12 (designated LABO). Example 2

[0086] The process is essentially identical to embodiment 1, except that in step (2) the total doping mass of lanthanum and niobium is regulated to 3%. Example 3

[0087] The process is essentially identical to embodiment 1, except that in step (2) the total doping mass of lanthanum and niobium is regulated to 5%. Example 4

[0088] The process is essentially identical to embodiment 1, except that in step (2) the total doping mass of lanthanum and niobium is regulated to 10%. Example 5 (1) Preparation of single-crystal LiNiXCoYMnzO2: Soluble sulfates of nickel, cobalt, and manganese were prepared in a specific molar ratio of nickel, cobalt, and manganese ions (85:10:5) to form a solution with a total molar concentration of metal ions of 1.0 mol / L. Subsequently, sodium hydroxide solution (concentration 4 mol / L) and ammonia solution (concentration 0.1 mol / L) were added successively and stirred. The co-precipitation reaction was carried out under a nitrogen atmosphere, maintaining a pH of 9 and a reaction temperature of 40 °C to obtain the hydroxide precursor (NiO0.85CoO0.10MnO0.05)(OH)2. The hydroxide precursor was washed, dried, and mixed with the fluxes LiOH and KCl. It was first sintered for 6 hours at 500 °C and then calcined for 15 hours at 800 °C. Finally, it was annealed in oxygen for 3 hours at 600 °C.This resulted in a single-crystal LiNi0,85Co0,10Mn0,05O2 powder from a ternary material with a high nickel content, Dv50 ≥ 4 µm and SPAN ≥ 1.6. (2) Preparation of the modified high-nickel material: LiNO3 and C4H4NNbO9·nH2O were added to ethanol in stoichiometric ratios as materials for the synthesis of Li6Nb2O8, with the addition of a single-crystal powder. The doping mass of niobium was adjusted to 3%. The solution was then stirred at 55 °C until the solvent had completely evaporated. The resulting mixture was calcined at 700 °C for 3 hours, yielding a 3 wt% modified high-nickel material, namely Li6Nb2O8 (designated as LBO). Example 6 (1) Preparation of single-crystal LiNiXCoYMnzO2: Soluble sulfates of nickel, cobalt, and manganese were prepared in a specific molar ratio of nickel, cobalt, and manganese ions (84:12:4) to form a solution with a total molar concentration of metal ions of 1.0 mol / L. Subsequently, sodium hydroxide solution (concentration 4 mol / L) and ammonia solution (concentration 0.1 mol / L) were added successively and stirred. The coprecipitation reaction was carried out under a nitrogen atmosphere, maintaining a pH of 9 and a reaction temperature of 40 °C to obtain the hydroxide precursor (NiO0.84CoO0.12MnO0.04)(OH)2. The hydroxide precursor was washed, dried, and mixed with the fluxes LiOH and KCl. It was first sintered for 6 hours at 500 °C and then calcined for 15 hours at 800 °C. Finally, it was annealed in oxygen for 3 hours at 600 °C.This resulted in a single-crystal LiNi0,84Co0,12Mn0,04O2 powder from a ternary material with a high nickel content, Dv50 ≥ 4 µm and SPAN ≥ 1.6. (2) Preparation of the modified high-nickel material: LiNO3 and C4H4NNbO9·nH2O were added to ethanol in stoichiometric ratios as materials for the synthesis of Li5La3O7, with the addition of a single-crystal ternary powder. The doping mass of lanthanum was adjusted to 3%. The solution was then stirred at 55 °C until the solvent had completely evaporated. The resulting mixture was calcined at 700 °C for 3 hours, yielding a 3 wt% modified high-nickel material, namely Li5La3O7 (designated as LAO). Example 7 (1) Preparation of single-crystal LiNiXCoYMnzO2: Soluble sulfates of nickel, cobalt, and manganese were prepared in a specific molar ratio of nickel, cobalt, and manganese ions (83:12:5) to form a solution with a total molar concentration of metal ions of 1.5 mol / L. Subsequently, sodium hydroxide solution (concentration 6 mol / L) and ammonia solution (concentration 0.3 mol / L) were added successively and stirred. The coprecipitation reaction was carried out under a nitrogen atmosphere, maintaining a pH of 10 and a reaction temperature of 55 °C to obtain the hydroxide precursor (NiO0.83CoO0.12MnO0.05)(OH)2. The hydroxide precursor was washed, dried, and mixed with the fluxes LiOH and KCl. It was first sintered for 7 hours at 300 °C and then calcined for 16 hours at 850 °C. Finally, it was annealed in oxygen for 4 hours at 400 °C.This resulted in a single-crystal LiNi0,83Co0,12Mn0,05O2 powder from a ternary material with a high nickel content, Dv50 ≥ 4 µm and SPAN ≥ 1.6. (2) Preparation of the modified high-nickel material: LiNO3 and C4H4NTiO9·nH2O were added to ethanol in stoichiometric ratios as materials for the synthesis of Li6Ti2O8, with the addition of a single-crystal powder. The doping mass of titanium was adjusted to 3%. The solution was then stirred at 45 °C until the solvent had completely evaporated. The resulting mixture was calcined at 600 °C for 3 hours, yielding a 3 wt% modified high-nickel material, namely Li6Ti2O8 (designated LBO). Example 8 (1) Preparation of single-crystal LiNiXCoYMnzO2: Soluble sulfates of nickel, cobalt, and manganese were prepared in a specific molar ratio of nickel, cobalt, and manganese ions (83:12:5) to form a solution with a total molar concentration of metal ions of 1.5 mol / L. Subsequently, sodium hydroxide solution (concentration 6 mol / L) and ammonia solution (concentration 0.3 mol / L) were added successively and stirred. The coprecipitation reaction was carried out under a nitrogen atmosphere, maintaining a pH of 10 and a reaction temperature of 55 °C to obtain the hydroxide precursor (NiO0.83CoO0.12MnO0.05)(OH)2. The hydroxide precursor was washed, dried, and mixed with the fluxes LiOH and KCl. It was first sintered for 6 hours at 350 °C and then calcined for 14 hours at 750 °C. Finally, it was annealed in oxygen for 4 hours at 450 °C.This resulted in a single-crystal LiNi0,83Co0,12Mn0,05O2 powder from a ternary material with a high nickel content, Dv50 ≥ 4 µm and SPAN ≥ 1.6. (2) Preparation of the modified high-nickel material: LiNO3 and Pr(CH3COO)3 were added to ethanol in stoichiometric ratios as materials for the synthesis of Li5Pr3O7, with the addition of a single-crystal ternary powder. The doping mass of praseodymium was adjusted to 3%. The solution was then stirred at 50 °C until the solvent had completely evaporated. The resulting mixture was calcined at 650 °C for 2 hours, yielding a 3 wt% modified high-nickel material, namely Li5Pr3O7 (designated as LAO). Example 9 (1) Preparation of single-crystal LiNiXCoYMnzO2: Soluble sulfates of nickel, cobalt, and manganese were prepared in a specific molar ratio of nickel, cobalt, and manganese ions (83:12:5) to form a solution with a total molar concentration of metal ions of 1.5 mol / L. Subsequently, sodium hydroxide solution (concentration 6 mol / L) and ammonia solution (concentration 0.3 mol / L) were added successively and stirred. The coprecipitation reaction was carried out under a nitrogen atmosphere, maintaining a pH of 10 and a reaction temperature of 55 °C to obtain the hydroxide precursor (NiO0.83CoO0.12MnO0.05)(OH)2. The hydroxide precursor was washed, dried, and mixed with the fluxes LiOH and KCl. It was first sintered for 5 hours at 400 °C and then calcined for 18 hours at 700 °C. Finally, it was annealed in oxygen for 3 hours at 550 °C.This resulted in a single-crystal LiNi0,83Co0,12Mn0,05O2 powder from a ternary material with a high nickel content, Dv50 ≥ 4 µm and SPAN ≥ 1.6. (2) Preparation of the modified high-nickel material: LiNO3, Ce(CH3COO)3, and C4H4NZrO9·nH2O were added to ethanol in stoichiometric ratios as materials for the synthesis of Li5Ce3Zr2O12, with the addition of a single-crystal ternary powder. The total doping mass of cerium and zirconium was adjusted to 3%. The solution was then stirred at 60 °C until the solvent had completely evaporated. The resulting mixture was calcined at 750 °C for 2 hours, yielding a 3 wt% modified high-nickel material, namely Li5Ce3Zr2O12 (designated LABO). Example 10 (1) Preparation of single-crystal LiNiXCoYMnzO2: Soluble sulfates of nickel, cobalt, and manganese were prepared in a specific molar ratio of nickel, cobalt, and manganese ions (83:12:5) to form a solution with a total molar concentration of metal ions of 1.5 mol / L. Subsequently, sodium hydroxide solution (concentration 6 mol / L) and ammonia solution (concentration 0.3 mol / L) were added successively and stirred. The coprecipitation reaction was carried out under a nitrogen atmosphere, maintaining a pH of 10 and a reaction temperature of 55 °C to obtain the hydroxide precursor (NiO0.83CoO0.12MnO0.05)(OH)2. The hydroxide precursor was washed, dried, and mixed with the fluxes LiOH and KCl. It was first sintered for 5 hours at 450 °C and then calcined for 12 hours at 900 °C. Finally, it was annealed in oxygen for 2 hours at 600 °C.This resulted in a single-crystal LiNi0,83Co0,12Mn0,05O2 powder from a ternary material with a high nickel content, Dv50 ≥ 4 µm and SPAN ≥ 1.6. (2) Preparation of the modified high-nickel material: LiNO3, Yb(CH3COO)3, and C4H4NMoO9·nH2O were added to ethanol in stoichiometric ratios as materials for the synthesis of Li5Yb3Mo2O12 (where X ≥ 5, Y ≥ 3, Z ≥ 2, X, Y, and Z are integers, A is yttrium, and B is molybdenum) by adding a single-crystal ternary powder. The total doping mass of ytterbium and molybdenum was adjusted to 3%. The solution was then stirred at 50 °C until the solvent had completely evaporated. The resulting mixture was calcined at 800 °C for 1 hour, yielding a 3 wt% modified high-nickel material, namely Li5Yb3Mo2O12 (designated LABO). Comparative example 1

[0089] Preparation of single-crystal LiNiXCoYMnzO₂: Soluble sulfates of nickel, cobalt, and manganese were prepared in a specific molar ratio of nickel, cobalt, and manganese ions (83:12:5) to form a solution with a total molar concentration of metal ions of 1.5 mol / L. Subsequently, sodium hydroxide solution (concentration 6 mol / L) and ammonia solution (concentration 0.3 mol / L) were added successively and stirred. The coprecipitation reaction was carried out under a nitrogen atmosphere, maintaining a pH of 10 and a reaction temperature of 55 °C, to obtain the hydroxide precursor (NiO₂,83CoO₂,12MnO₂,05)(OH)₂. The hydroxide precursor was washed, dried, and mixed with the fluxes LiOH and KCl. It was first sintered for 6 hours at 500 °C and then calcined for 15 hours at 800 °C. Finally, it was annealed in oxygen for 3 hours at 600 °C.This resulted in a single-crystal LiNi0,83Co0,12Mn0,05O2 powder from a ternary material with a high nickel content, Dv50 ≥ 4 µm and SPAN ≥ 1.6.

[0090] The modified high-nickel materials produced in embodiments 1 to 10 were combined with the high-nickel material produced in comparative example 1 to form positive electrode sheets. These were then assembled into lithium-ion batteries for performance testing. The detailed procedures and results are as follows: (1) Production of the negative electrode sheet:

[0091] The active materials graphite, silicon, the conductive agent carbon black, a polymer material, and the thickening agent sodium carboxymethylcellulose (CMC) were dissolved in deionized water in a weight ratio of 90:5:2:2:1. This mixture was blended to produce the negative electrode paste. The negative electrode paste was then applied to copper foil, dried, cold-pressed, and cut to produce the negative electrode sheet. (2) Production of the positive electrode sheet:

[0092] The positive electrode active material (high-nickel material, produced in embodiments 1 to 10 and comparative example 1), the conductive agent acetylene carbon black, and the binder polyvinylidene fluoride (PVDF) were dissolved in the solvent N-methylpyrrolidone (NMP) in a weight ratio of 96.5:1.5:2. After thorough stirring to ensure uniform mixing, the positive electrode paste is obtained. This paste is then applied evenly to the positive electrode current collector, which is coated with a primer. After drying, cold pressing, and cutting, the positive electrode sheet is obtained. (3) Separator:

[0093] The separator consists of PE with a surface coating of PVDF and aluminium oxide to improve adhesion and heat resistance. (4) Electrolyte solution:

[0094] The electrolyte solution is prepared by mixing vinylene carbonate (EC), ethyl methyl carbonate (EMC), and diethyl carbonate (DEC) in a volume ratio of 1:1:1. LiPF6:LiFSI (2:8) is then dissolved uniformly in this solution to obtain the electrolyte solution. The concentration of the lithium salt in this electrolyte solution is 1 mol / L. (5) Assembly of lithium-ion batteries:

[0095] The positive electrode sheet, separator, and negative electrode sheet are stacked sequentially, with the separator positioned between the positive and negative electrode sheets for insulation. The assembly is then wound into a bare cell. Electrode tabs are welded to the bare cell, which is then inserted into an aluminum casing. The assembly is baked at 80°C to remove moisture. The electrolyte solution is then added, and the assembly is sealed, creating an uncharged battery. These uncharged batteries then undergo a series of processes, including resting, hot and cold pressing, forming, reshaping, and capacity testing, to manufacture lithium-ion battery products. (6) Performance tests: 1. Capacity test: ① Leave to stand for 30 minutes; 2. Charge at a rate of 1 / 3C to 4.25V and then charge at a constant voltage of 4.25V to 0.05C to complete the charging process; ③ Leave to stand for 30 minutes; ④ Discharge at a rate of 1 / 3C to 2.8V to obtain the capacity C0;

[0096] The energy gained is the battery energy; the weight energy density corresponds to the energy divided by the weight of the battery. 2. DCR test:

[0097] After manufacturing, the secondary battery is left to rest for 30 minutes at 25°C. It is then charged at a rate of 1 / 3C to 4.25V, followed by a constant-voltage charge at 0.05C until complete. After a 10-minute rest period, it is discharged at a rate of 1 / 3C until the cell's capacity reaches 10% of its full charge, referred to as 10% SOC. After a 60-minute rest period, it is discharged for 10 seconds at a rate of 4C, and the cell's DCR value is recorded. 3. Storage test: ① Leave fresh cells at room temperature for 30 minutes; 2. Charge at a rate of 1 / 3C to 4.25V and then charge at a constant voltage of 4.25V to 0.05C to complete the charging process; ③ Leave to stand for 30 minutes; ④ Discharge at a rate of 1 / 3C to 2.8V to obtain the capacity C0; 2. Store at 60°C and 97% SOC. Remove the battery once every 10 days to test its capacity, which is specified as Cn. Continue until Cn has dropped to 80% of C0 to determine the appropriate storage duration.

[0098] 4. Testing of element doping concentration: Performed by inductively coupled plasma spectrometry (ICP) in accordance with the relevant test standards YS / T 1006.2-2014, GB / T 23367.2-2009 or YS / T 1028.5-2015. 5. Cycle test: ① Set the temperature to 25 °C and keep it constant for 2 hours: 2. Let stand for 5 minutes; ③ Charge at a rate of 1 / 3C to 4.3V and then charge at a constant voltage of 4.3V to 0.05C to complete the charging process; 5. Let stand for 5 minutes; ⑤ Discharge at a rate of 1 / 2 C0 to 2.8 V; ⑥ Let stand for 5 minutes; ⑦ Repeat steps ③, ④, ⑤ and ⑥ until the capacity decrease is ≤ 80%, and thus determine the corresponding number of cycles of service life.

[0099] The test results are summarized in Table 2 below.

[0100] In Table 2, the energy density ranges are categorized as follows: moderate 258 to 260 Wh / kg, moderately high 260 to 262 Wh / kg and high 262 to 264 Wh / kg;

[0101] Table 2 defines the DCR step ranges as follows: low 0.8 to 1.0 mΩ, moderate 1.0 to 1.2 mΩ, moderately high 1.2 to 1.4 mΩ and high 1.4 to 1.6 mΩ.

[0102] Table 2 Performance tests of the individual embodiments and the comparison example [Table 2] Doping quantity pollution Single crystal size Dv50 (4 µm) Energy density (Wh / kg) 25°C 10%SOC DCR(mΩ) Cycle lifetime at 25°C and 2.8 to 4.3 V (in cycles) Storage at 60 °C and 4.3 V (in days) Comparative example 1 - - 5 High High 1200 280 Example 1 1% LABO 5 Moderately high Moderate 2000 500 Example 2 3 % LABO 5 High Low 2500 900 Example 3 5 % LABO 5 High Low 2200 800 Example 4 10% LABO 5 Moderate Moderately high 2000 700 Example 5 3 % LBO 5 High Moderately high 1900 600 Example 6 3 % LAO 5 High Low 1600 800 Example 7 3 % LBO 5 High Moderately high 1900 600 Example 8 3 % LAO 5 High Low 1600 800 Example 9 3 % LABO 5 High Low 2500 900 Example 10 3 % LABO 5 High Low 2500 900

[0103] As shown in Table 2, doping with the lanthanide element La in embodiment 5 improves the kinetics, reduces DCR, increases structural stability, and improves cycle and storage performance. Doping with metallic Nb in embodiment 8 also improves structural stability and increases cycle and storage performance. However, compared to the combined doping with both metallic elements in embodiment 4, the combined doping approach offers greater advantages. In embodiments 7 to 10, replacing the lanthanide element La with other metallic elements according to the invention and / or replacing the metal Nb with other metallic elements according to the invention improves both cycle and storage performance.

[0104] The foregoing merely presents preferred embodiments of the present application and is not intended to limit the scope of the patent claims contained herein. Various modifications and variations of the present application are possible for those skilled in the art. All modifications, equivalent replacements, improvements, etc., made in accordance with the principles of the present application shall be covered by the patent protection claimed herein. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited non-patent literature

[0000] Testnormen YS / T 1006.2-2014, GB / T 23367.2-2009 oder YS / T 1028.5-2015

[0098]

Claims

Positive electrode material, characterized in that the positive electrode material comprises a positive electrode material particle, wherein the positive electrode material particle comprises a substrate and a modifying element, wherein: the substrate contains LiNixCoyMnzO2, where x ≥ 0.8, y ≤ 0.12 and x + y + z = 1; and the modifying element comprises a rare earth element and / or a high-melting-point metal element. Positive electrode material according to claim 1, characterized in that the rare earth element is located at least partially on the surface of the substrate; and / or the high-melting-point metal element is located at least partially inside the substrate. Positive electrode material according to claim 1, characterized in that the rare earth element comprises at least one of the elements lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium; and / or that the high-melting-point metal element comprises at least one of the elements titanium, zirconium, niobium, vanadium, molybdenum and tungsten. Positive electrode material according to claim 1, characterized in that the rare earth element is lanthanum; and / or the high-melting-point metallic element is niobium. Positive electrode material according to claim 1, characterized in that the modifying element is introduced into the substrate by doping. Positive electrode material according to claim 1, characterized in that, based on the mass of the positive electrode material of 100%, the doping mass of the modifying element is 1% to 10%. Positive electrode material according to claim 1, characterized in that, based on the mass of the positive electrode material of 100%, the doping mass of the modifying element is 3% to 5%. Positive electrode material according to claim 1, characterized in that the LiNixCoyMnzO2 is a single crystal particle. Positive electrode material according to claim 1, characterized in that the Dv50 value of the LiNixCoyMnzO2 is ≥ 4 µm; and / or, the SPAN value of the LiNixCoyMnzO2 is ≥ 1.

6. Positive electrode material according to any one of claims 1 to 9, characterized in that it is produced by a manufacturing process wherein: a modifier is mixed with the LiNixCoyMnzO2 and the positive electrode material is obtained by calcination, wherein in LiNixCoyMnzO2 x ≥ 0.8, y ≤ 0.12 and x + y + z = 1; wherein the modifier comprises a rare earth element and / or a high-melting-point metal element. Positive electrode material according to claim 10, characterized in that the modifier comprises LiXAYBZO(X+3Y+5Z) / 2, LiXAYO(X+3Y) / 2 or LiXBZO(X+5Z) / 2, wherein X≥5, Y≥3, Z≥2 and X, Y, Z are integers, A is one of lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium or lutetium and B is one of titanium, zirconium, niobium, vanadium, molybdenum or tungsten. Positive electrode material according to claim 10, characterized in that the calcination temperature is 600 °C to 800 °C and the calcination time is 1 to 3 hours. Positive electrode sheet, characterized in that the positive electrode sheet comprises the positive electrode material according to any one of claims 1 to 9. Secondary battery, characterized in that the secondary battery comprises the positive electrode sheet according to claim 13. Power-consuming device, characterized in that the power-consuming device comprises the secondary battery according to claim 14.

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