Composite material containing lithium supplement agent and layered positive electrode material as well as preparation method and application of composite material

Abstract

The invention discloses a composite material containing a lithium supplement agent and a layered positive electrode material, which adopts a multi-layer structure and comprises the lithium supplement agent, a main active substance layered positive electrode material and a carbon coating layer, and can contain or does not contain a coating layer of other elements except carbon. Wherein the lithium supplement agent is mainly used for improving the first efficiency and the cycle performance of the battery cell; the layered positive electrode material is used as a main active material and can improve the air stability after being coated; the carbon layer which can be contained or not contained is mainly used for improving the electronic conductivity and air stability of the material; the coating layer containing or not containing other elements is mainly used for improving the electrical property and improving the air stability to a certain degree. The composite material containing the lithium supplement agent and the layered positive electrode material disclosed by the invention can be used as a high-capacity lithium supplement additive when the content of the lithium supplement agent is high, can be used as a lithium supplement additive with a moderate addition amount when the content of the lithium supplement agent is moderate, is suitable for uniformly supplementing lithium, and solves the problem of local lithium precipitation caused by non-uniform dispersion of the high-capacity lithium supplement agent. When the content of the lithium supplement agent is low, the material can be used as a positive electrode material containing a small amount of the lithium supplement agent.

Description

Technical Field

[0001] This invention relates to the field of composite materials technology for lithium-ion batteries containing lithium replenishing agents and layered cathode materials, and particularly to a composite material containing lithium replenishing agents and layered cathode materials, its preparation method and application. Background Technology

[0002] With the widespread application of lithium-ion batteries in various fields, improving their performance has become a hot research topic in the industry. Lithium-ion batteries (LIBs) need to provide high energy density and long cycle life to meet the growing demands of electric vehicle batteries. However, significant irreversible capacity loss occurs during the initial cycle, mainly due to the formation of a solid electrolyte interface (SEI) on the negative electrode surface, which greatly reduces the energy density and cycle life of the complete battery. Fortunately, various anode and cathode pre-lithiation technologies have been developed to address this critical issue. Pre-lithiation compensates for the initial active lithium loss (ALL), effectively improving cycle life and energy density while maintaining compatibility with current commercial LIB production.

[0003] Lithium replenishment agents, as key materials, play a crucial role in improving the cycle life performance of energy storage batteries. They can mitigate the problem of reduced initial coulombic efficiency at the negative electrode, thereby increasing the capacity, cycle life, and energy density of lithium batteries. Lithium replenishment technology involves adding lithium ions into the battery before it begins operation to replenish the lithium consumed by the solid electrolyte interphase (SEI) film formed during the first charge, thus reducing irreversible lithium loss at the positive electrode and improving the battery's initial efficiency and cycle life.

[0004] Lithium-rich nickel oxide (LNO, chemical formula Li₂NiO₂) is currently the mainstream cathode lithium supplement material. LNO is a lithium metal oxide with an anti-fluorite structure, and due to its high specific capacity, it has become the mainstream cathode lithium supplement agent. On the other hand, high-energy-density batteries generally use layered cathode materials; thus, LFO and LFP have some incompatibility in their chemical systems. Therefore, from the perspective of chemical system compatibility, using uniform LFP coating will allow LFO to be better compatible with layered cathode material energy storage systems, while suppressing gas generation and other problems, achieving optimal performance.

[0005] CN119965268A discloses that its core uses nitrogen-modified lithium-rich nickel oxide (LNO), which is sintered at high temperature to produce lithium nitride-coated LNO. Simultaneously, carbon coating improves its air stability and electronic conductivity. However, lithium nitride is prone to hydrolysis, generating lithium hydroxide and ammonia gas. Finely powdered lithium nitride, in particular, can undergo violent combustion when heated in air. Therefore, lithium nitride must be processed in an inert atmosphere (such as nitrogen). Consequently, the production conditions for this coated product are harsh, and its storage and transportation are challenging.

[0006] Furthermore, Chinese Patent Publication No. CN116845191A discloses a self-lithiated ternary material with a core-shell structure. The core is a ternary material, and the shell comprises two coating layers: lithium-rich nickel oxide (Li₂NiO₂) and a carbon coating layer, from the inside out. The lithium-rich nickel oxide (Li₂NiO₂) accounts for 1.0-5.0% of the total weight of the self-lithiated ternary material, and the carbon coating layer accounts for 1.0-2.0%. However, lithium-rich nickel oxide exhibits significantly higher air stability and a faster reaction rate with water compared to ternary materials.

[0007] The described preparation process utilizes the extreme sensitivity of ternary materials to moisture. Upon contact with water, the surface structure is restructured, generating a uniform layer of NiOOH. Subsequently, high-temperature calcination decomposes the NiOOH into NiO. NiO reacts with lithium sources such as lithium oxide in an inert atmosphere to generate lithium-rich nickel oxide (Li₂NiO₂), resulting in a ternary material uniformly coated with Li₂NiO₂. A carbon source is introduced during the reaction of NiO with the lithium source, and after high-temperature calcination, a dense carbon coating layer is formed in situ on the surface of the self-lithiated ternary material, resulting in a ternary material with a double coating layer. Therefore, its core structure is a ternary material, with Li₂NiO₂ and a carbon coating layer. Furthermore, the reaction of the ternary material upon contact with water should be LiNiCoMnO₂ + H₂O → Li⁺ + OH⁻ + Ni / Co / Mn oxides or hydroxides. Moreover, during the preparation process, it is highly likely that only NiOOH will be formed, and a ternary material is very likely to be formed after high-temperature recalcination. Furthermore, no additional lithium source was added during the reheating process. Instead, the preparation process utilizes the side reaction of ternary materials and water, which actually reduces the lithium source. In particular, when some lithium hydroxide is generated in the structural formula, the water solubility of lithium hydroxide is much stronger than that of Ni / Co / Mn oxides or hydroxides. Therefore, its surface will only be a lithium-deficient Ni / Co / Mn oxide, and it is impossible to form a lithium-rich Li2NiO2.

[0008] This solution proposes a composite material containing a lithium supplement and layered oxides. The composite material mainly consists of two core substances (lithium supplement a, layered cathode material b, a+b=100 parts) and a carbon coating layer (optional) and other elemental coating layers (optional). When the lithium supplement content is high (e.g., 90≤a≤100), this composite material can be used as a lithium supplement additive, requiring only a small amount for lithium supplementation. At a moderate lithium supplement content (e.g., 10≤a≤90), it facilitates uniform lithium supplementation, making it more suitable for uniform lithium supplementation. Conversely, when the lithium supplement content is low (meaning a high layered cathode material content), the composite material can be used as a cathode material containing a lithium supplement (0≤a≤10), achieving long-cycle operation without the need for additional lithium supplement. This invention patent allows for different application areas by varying the proportions of lithium supplement and layered cathode materials. Summary of the Invention

[0009] The purpose of this invention is to provide a composite material whose lithium replenishment capacity can be achieved by adjusting the ratio of lithium replenishing agent and iron phosphate, even with a high lithium replenishing agent content. While adding only a small amount of this composite material can achieve high-capacity lithium replenishment, it may lead to uneven lithium replenishment and the risk of lithium plating. For example, (90≤a≤100), only a small amount of this composite material is needed for lithium replenishment, and a moderate lithium replenishing agent content (10≤a≤90) facilitates more uniform lithium replenishment. Conversely, a low lithium replenishing agent content implies a high layered cathode material content, and this composite material can be used as a cathode material containing a lithium replenishing agent (0≤a≤10), enabling long-cycle operation without the need for additional lithium replenishing agent.

[0010] A composite material containing a lithium supplement and a layered cathode material allows for seamless switching between different application scenarios by adjusting the ratio of the lithium supplement and the layered cathode material. Furthermore, the excellent coating of the layered cathode material improves the air stability of the lithium supplement while suppressing gas generation, thus optimizing performance and mitigating the incompatibility issues of the chemical system to some extent.

[0011] To achieve the above objectives, the present invention adopts the following technical solution:

[0012] In a first aspect, the present invention provides a multi-layered composite material containing a lithium replenishing agent and a layered cathode material. This material has a multi-layered structure, comprising a lithium replenishing agent, a main active material (layered cathode material), a carbon coating layer, and a coating layer containing or not containing elements other than carbon. The weight of the lithium replenishing agent (a) + the weight of the active material (b) = 100 parts. Wherein 0 ≤ a ≤ 90 parts; 0 ≤ b < 100; 0 < c ≤ 10; 0 ≤ d ≤ 1%.

[0013] As a specific technical solution, when the lithium replenishing agent content is high, as a high-capacity lithium replenishing agent, only a small amount of this composite material needs to be added to achieve the lithium replenishing effect. At this time, the content of the composite material as the lithium replenishing agent can be 90≤a≤100, specifically 100 parts, 98 parts, 96 parts, 94 parts, 92 parts, 90 parts, or any numerical ratio therein. The content of the layered cathode material can be 0≤b≤10, specifically 0 parts, 2 parts, 4 parts, 6 parts, 8 parts, 10 parts, or any numerical ratio therein.

[0014] When the lithium replenishing agent content is moderate, this composite material can be used as a medium-capacity lithium replenishing agent and is suitable as a uniform lithium replenishing additive. The content of the layered cathode material can be 10≤a≤90; specifically, it can be 90 parts, 80 parts, 70 parts, 60 parts, 50 parts, 40 parts, 30 parts, 20 parts, 10 parts, or any numerical ratio therein.

[0015] When the lithium replenisher content is low, this composite material can be used as a long-cycle cathode material. The lithium replenisher content in this composite material ranges from 0 ≤ a ≤ 10, specifically 10 parts, 8 parts, 7 parts, 6 parts, 4 parts, 2 parts, 1 part, or any numerical ratio therein. The content of the layered cathode material can be 90 ≤ b ≤ 100, specifically 90 parts, 92 parts, 94 parts, 96 parts, 98 parts, 100 parts, or any numerical ratio therein.

[0016] Furthermore, the carbon content is 0 ≤ c ≤ 10%; it can be 0%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or any numerical proportion therein. The carbon content is preferably 0 ≤ c ≤ 5%, more preferably 0 ≤ c ≤ 3%. The thickness of the carbon coating is set to ≤ 100 nm, more preferably ≤ 50 nm; even more preferably ≤ 20 nm.

[0017] Secondly, the present invention provides a method for preparing the above-mentioned composite material, comprising the following steps:

[0018] S1. Preparation of lithium supplement precursor: Weigh a nickel source, dissolve it in deionized water, and prepare a solution of a certain concentration; add a precipitant and a complexing agent, and after a period of reaction, obtain hydroxide, wash and dry to obtain lithium supplement precursor.

[0019] S2. Preparation of layered cathode material precursor: Prepare solutions of nickel salt, cobalt salt, manganese salt, or aluminum salt. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly. Disperse the lithium supplementation agent precursor from S1 evenly in the layered cathode precursor solution. Add the precipitant solution, complexing agent, and the mixture to a reactor in parallel flow for reaction and precipitation. After sufficient reaction, allow the mixture to stand and age. Perform solid-liquid separation on the aged solution and wash it.

[0020] S3, Preparation of composite material containing lithium supplementation agent and layered cathode: The S2 precursor is thoroughly mixed with lithium source and carbon source (which may be added in proportion or not) and sintered under atmospheric conditions.

[0021] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0022] The steps of the second physical preparation method are as follows:

[0023] S1. Weigh the lithium supplement precursor and lithium source according to the proportion, control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the first material;

[0024] S2. Weigh the layered cathode material precursor and lithium source according to the ratio, grind to control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the second material;

[0025] S3, combine the first material obtained in step S1 and the second material obtained in step S2 with...

[0026] A carbon source can be added in proportion or not, mixed evenly, ground, and dried after controlling the D50 particle size to ≤0.5μm to obtain precursor powder;

[0027] S4. The precursor powder obtained in step S3 is placed into a furnace with an atmosphere for the first sintering. The sintering temperature is 400℃~650℃ and the holding time is 4h~16h to obtain the first sintering product.

[0028] S5. The first sintering product obtained in step S4 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0029] As a specific technical solution, in step S1, the nickel source includes nickel carbonate, nickel hydroxide, nickel nitrate, nickel sulfate, nickel oxide, nickel greening, nickel oxalate, nickel acetate, nickel citrate, and nickel sulfate. The mol concentration range of the nickel source is: 0 ≤ nickel source concentration ≤ 50 mol / L, preferably 0 ≤ nickel source concentration ≤ 20 mol / L; more preferably 0 ≤ nickel source concentration ≤ 10 mol / L.

[0030] As a specific technical solution, in step S1, the precipitant can be an aqueous solution of sodium hydroxide or lithium hydroxide, with a mass concentration range of 5% ≤ precipitant aqueous solution concentration ≤ 60%; preferably 10% ≤ precipitant aqueous solution concentration ≤ 50%; more preferably 20% ≤ precipitant aqueous solution concentration ≤ 40%.

[0031] As a specific technical solution, in step S1, the complexing agent is an ammonia solution, and its mass concentration ranges from 5% to 60%; preferably, it is 10% to 50%; more preferably, it is 20% to 40%.

[0032] As a specific technical solution, in step S1, 0 ≤ reaction time ≤ 48h, preferably 5 ≤ reaction time ≤ 24h, and more preferably 5 ≤ reaction time ≤ 12h.

[0033] As a specific technical solution, the precursor of the layered cathode material can be a solution of nickel salt, cobalt salt, manganese salt or aluminum salt, wherein the nickel salt, cobalt salt, manganese salt or aluminum salt is at least one or more of sulfate, nitrate, acetate or halide salt.

[0034] As a specific technical solution, the lithium source includes one or a combination of two or more of lithium carbonate, lithium oxide, lithium hydroxide, lithium acetate, lithium citrate, lithium oxalate, and lithium adipic acid.

[0035] As a specific technical solution, the carbon source includes inorganic carbon sources and / or organic carbon sources.

[0036] The inorganic carbon source includes at least one of carbon nanotubes, graphene, graphite, fullerene, and amorphous carbon. As an example, the fullerene may be C2. 20 C 60 C 70 C 76 C 80 wait.

[0037] The organic carbon source includes one or more of the following: glucose, hydroxymethyl cellulose, sucrose, soluble starch, PEG, hydroxyethyl cellulose, petroleum, and asphalt.

[0038] As a specific technical solution, in step S2, the amount of carbon source added is ≤ 10% of the weight of (lithium supplement + layered cathode material). As an example, the amount of carbon source added can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc., or any value therein.

[0039] As a specific technical solution, the molar ratio of lithium to nickel in the lithium replenishing agent is in the range of (1.9~2.2):1.

[0040] Preferably, the molar ratio of lithium to nickel in the lithium supplement is (1.9~2.2):1.

[0041] For example, the molar ratio of lithium to nickel in the lithium supplement is 1:2.05, 1:2.10, or 1:2.15.

[0042] As a specific technical solution, the drying process adopts any one of spray drying, flash drying, or centrifugal drying.

[0043] As an example, the drying process can be spray drying, with an inlet temperature ≥180℃ and an outlet temperature ≥90℃.

[0044] As a specific technical solution, the atmosphere is one or a combination of two or more of oxygen, nitrogen, argon, and air.

[0045] As a specific technical solution, the surface coating elements include oxides, hydroxides, sulfates, nitrates, and other salts of B, N, Mg, Al, F, Si, P, S, K, Ca, Sc, V, Ti, Cr, Mn, Ni, Ga, Ge, La, Se, Rb, Sr, Y, Nb, Mo, Ru, Eu, Er, Yb, Dy, Cs, Sb, Sn, Se, Te, Bi, Zn, Cu, Ce, Rh, Tb, Lu, Hf, Ta, W, Os, Ir, Pt, Au, Pb, Zr, Cd, Pd, Ag, etc. Specifically, it can be one or a combination of two or more of the following: alumina, boehmite, zirconium oxide, zinc oxide, titanium oxide, calcium dioxide, silicon dioxide, magnesium oxide, tin oxide, nickel oxide, cobalt oxide, manganese oxide, phosphorus pentoxide, tantalum oxide, tungsten oxide, niobium oxide, strontium oxide, cerium oxide, and lanthanum oxide.

[0046] As a specific technical solution, in step S5, the coating amount of the surface coating agent is ≤1% (10000ppm).

[0047] Preferably, the coating amount of the surface coating agent is ≤8000ppm.

[0048] Preferably, the coating amount of the surface coating agent is ≤6000ppm.

[0049] As a specific technical solution, the D50 particle size of the surface coating agent is ≤500nm.

[0050] Preferably, the D50 particle size of the surface coating agent is ≤100nm.

[0051] Preferably, the D50 particle size of the surface coating agent is ≤50nm.

[0052] In a specific technical solution, the physical coating method controls the grinding particle size D50 to be ≤0.5μm, preferably ≤0.4μm, and more preferably ≤0.2μm.

[0053] As a specific technical solution, the gas encapsulated during CVD deposition is any one of acetylene, ethylene, methane, ethane, and propane.

[0054] As a specific technical solution, the CVD deposition process is carried out at a temperature of 700℃~900℃ for 2h~16h.

[0055] As a specific technical solution, after CVD deposition, the particles are pulverized to a D50 particle size ≤10μm, and more preferably, the particle size is ≤5μm.

[0056] Thirdly, the present invention also provides the application of a composite material prepared according to the above-described composite material containing lithium supplement and active material or the preparation method thereof in a battery, wherein the battery includes any one of lithium-ion batteries, solid-state batteries, and semi-solid-state batteries.

[0057] Compared to existing technologies, this composite material, by adjusting the ratio of lithium replenisher and iron phosphate, achieves high lithium replenishment capacity even with high lithium replenisher content. While only a small amount of this composite material is needed to achieve high-capacity lithium replenishment, it may lead to uneven lithium replenishment and the risk of lithium plating. At moderate lithium replenisher content (10≤a≤90), it can serve as a uniform lithium replenishment additive. A moderate amount of the composite material further enhances uniform lithium replenishment, thus avoiding the risk of localized lithium plating. At low lithium replenisher content (0≤a≤10), especially when the lithium replenisher content is between approximately 2-5%, it can serve as a long-cycle cathode material, achieving long-cycle operation without the need for additional lithium replenisher.

[0058] A composite material containing a lithium replenisher and a layered cathode material allows for flexible switching between different application scenarios by adjusting the ratio of the lithium replenisher and the layered cathode material. Furthermore, the excellent coating of the layered cathode material can improve the air stability of LFO (Liquid Oxide Foam) while suppressing gas generation, achieving optimal performance and, to some extent, solving the incompatibility problem of the chemical system, effectively improving the cycle life of the energy storage battery. Attached Figure Description

[0059] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0060] Figure 1 This is a schematic diagram illustrating the preparation of the composite material containing lithium supplementer and layered cathode material of the present invention.

[0061] Schematic diagram of the reaction process and structure of the composite material when used as a lithium replenishing agent with high lithium replenishment capacity.

[0062] (Suitable as a lithium supplement reagent with small additions)

[0063] Figure 2 Schematic diagram of the reaction process and structure of the composite material when used as a lithium supplement agent with medium lithium supplementation capacity.

[0064] (Suitable for uniform lithium replenishment)

[0065] Figure 3 A schematic diagram of the composite material reaction process and structure when used as a high-capacity layered cathode material (cathode material with built-in lithium replenishment). Detailed Implementation

[0066] The technical solution of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0067] Unless otherwise specified, the experimental methods used in the examples and comparative examples are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0068] The present invention will now be described in further detail through detailed embodiments and in conjunction with the accompanying drawings.

[0069] Example 1

[0070] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement is 2% and the layered cathode material is 98% (this scheme is an in-situ grown layered oxide technology). Figure 3 As shown, the preparation method of this composite material is as follows:

[0071] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0072] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0073] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0074] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0075] Example 2

[0076] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 4% and the layered cathode material comprises 96% (this scheme is an in-situ grown layered oxide technology). Figure 3 As shown, the preparation method of this composite material is as follows:

[0077] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0078] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0079] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0080] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0081] Example 3

[0082] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 6% and the layered cathode material comprises 94% (this scheme is an in-situ grown layered oxide technology). Figure 3 As shown, the preparation method of this composite material is as follows:

[0083] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0084] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0085] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0086] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0087] Example 4

[0088] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 8% and the layered cathode material comprises 92% (this scheme is an in-situ grown layered oxide technology). Figure 3 As shown, the preparation method of this composite material is as follows:

[0089] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0090] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0091] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0092] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0093] Example 5

[0094] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 10% and the layered cathode material comprises 90% (this scheme is an in-situ grown layered oxide technology). Figure 3 As shown, the preparation method of this composite material is as follows:

[0095] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0096] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0097] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0098] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0099] Example 6

[0100] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 20% and the layered cathode material comprises 80% (this scheme is an in-situ grown layered oxide technology). Figure 2 As shown, the preparation method of this composite material is as follows:

[0101] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0102] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0103] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0104] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0105] Example 7

[0106] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 30% and the layered cathode material comprises 70% (this scheme is an in-situ grown layered oxide technology). Figure 2 As shown, the preparation method of this composite material is as follows:

[0107] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0108] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0109] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0110] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0111] Example 8

[0112] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 40% and the layered cathode material comprises 60% (this scheme is an in-situ grown layered oxide technology). Figure 2 As shown, the preparation method of this composite material is as follows:

[0113] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0114] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0115] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0116] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0117] Example 9

[0118] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 50% and the layered cathode material comprises 50% (this scheme is an in-situ grown layered oxide technology). Figure 2 As shown, the preparation method of this composite material is as follows:

[0119] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0120] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0121] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0122] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0123] Example 10

[0124] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 60% and the layered cathode material comprises 40% (this scheme is an in-situ grown layered oxide technology). Figure 2 As shown, the preparation method of this composite material is as follows:

[0125] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0126] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0127] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0128] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0129] Example 11

[0130] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 70% and the layered cathode material comprises 30% (this scheme is an in-situ grown layered oxide technology). Figure 2 As shown, the preparation method of this composite material is as follows:

[0131] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0132] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0133] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0134] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0135] Example 12

[0136] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 80% and the layered cathode material comprises 20% (this scheme is an in-situ grown layered oxide technology). Figure 2 As shown, the preparation method of this composite material is as follows:

[0137] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0138] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0139] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0140] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0141] Example 13

[0142] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 90% and the layered cathode material comprises 10% (this scheme is an in-situ grown layered oxide technology). Figure 2 As shown, the preparation method of this composite material is as follows:

[0143] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0144] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0145] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0146] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0147] Example 14

[0148] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 92% and the layered cathode material comprises 8% (this scheme is an in-situ grown layered oxide technology). Figure 1 As shown, the preparation method of this composite material is as follows:

[0149] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0150] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0151] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0152] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0153] Example 15

[0154] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 96% and the layered cathode material comprises 4% (this scheme is an in-situ grown layered oxide technology). Figure 1 As shown, the preparation method of this composite material is as follows:

[0155] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0156] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0157] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0158] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0159] Example 16

[0160] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 94% and the layered cathode material comprises 6% (this scheme is an in-situ grown layered oxide technology). Figure 1 As shown, the preparation method of this composite material is as follows:

[0161] S1. Preparation of lithium supplement precursor: Weigh a nickel source, the molar ratio of which is 2% of the lithium supplement content, and dissolve it in deionized water to prepare a solution with a certain concentration of 3 mol / L; add a lithium hydroxide solution with a precipitant mass concentration of 30% and an ammonia aqueous solution with a complexing agent concentration of 34.7%; after a reaction time of 12 h, the hydroxide is obtained, washed and dried to obtain the lithium supplement precursor.

[0162] S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt, or aluminum salt solutions. Mix the nickel salt, cobalt salt, manganese salt, or aluminum salt solutions evenly (Ni:Co:Mn / Al in a molar ratio of 60:20:20). Prepare a layered precursor solution with a metal salt concentration of 2.2 mol / L. Disperse the above-mentioned S1 lithium supplement precursor powder evenly in the layered cathode precursor solution. Add a 30% sodium hydroxide solution (precipitant) and a 34.7% ammonia solution (complexing agent) to the reaction vessel in parallel flow with the mixture for 12 hours to precipitate. After sufficient reaction, allow to stand and age for 12 hours. Perform solid-liquid separation and washing on the aged solution.

[0163] S3. Preparation of a composite material containing a lithium supplement and a layered cathode: The S2 precursor is mixed with a lithium source, and the molar ratio of nickel in the lithium source and lithium supplement is (2.06:1), and the molar ratio of lithium source to layered oxide is (1.03:1). 2% glucose can be added in a specific ratio. The mixture is thoroughly mixed, sintered under a suitable atmosphere, and the sintered material is then crushed, graded, and demagnetized to obtain the desired material.

[0164] S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0165] Example 17

[0166] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 92% and the layered cathode material comprises 8% (this scheme is a physical coating iron oxide technology scheme). Figure 1 As shown, the preparation method of this composite material is as follows:

[0167] S1. Weigh the lithium supplement precursor and lithium source according to the proportion, control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the first material;

[0168] S2. Weigh the layered cathode material precursor and lithium source in proportion (Ni:Co:Mn=60:20:20), grind to control the D50 particle size ≤1μm, and further grind to control the D50 particle size ≤0.5μm to obtain the second material;

[0169] S3, combine the first material obtained in step S1 and the second material obtained in step S2 with...

[0170] A carbon source can be added in proportion or not, mixed evenly, ground, and dried after controlling the D50 particle size to ≤0.5μm to obtain precursor powder;

[0171] S4. The precursor powder obtained in step S3 is placed into a furnace with an atmosphere for the first sintering. The sintering temperature is 400℃~650℃ and the holding time is 4h~16h to obtain the first sintering product.

[0172] S5. The first sintering product obtained in step S4 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0173] Example 18

[0174] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 2% and the layered cathode material comprises 98% (this is a physical coating technology). Figure 1 As shown, the preparation method of this composite material is as follows:

[0175] S1. Weigh the lithium supplement precursor and lithium source according to the proportion, control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the first material;

[0176] S2. Weigh the layered cathode material precursor and lithium source according to the ratio, grind to control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the second material;

[0177] S3. Add 2% of the first material obtained in step S1 and 98% of the second material obtained in step S2 in a certain proportion, and add 2% glucose in a certain proportion. Mix evenly, grind, control the D50 particle size ≤ 0.5μm, and then dry to obtain precursor powder.

[0178] S4. The precursor powder obtained in step S3 is placed into a furnace with an atmosphere for the first sintering. The sintering temperature is 400℃~650℃ and the holding time is 4h~16h to obtain the first sintering product.

[0179] S5. The first sintering product obtained in step S4 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0180] Example 19

[0181] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 4% and the layered cathode material comprises 96% (this scheme is a physical coating iron oxide technology scheme). Figure 1 As shown, the preparation method of this composite material is as follows:

[0182] S1. Weigh the lithium supplement precursor and lithium source according to the proportion, control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the first material;

[0183] S2. Weigh the layered cathode material precursor and lithium source in proportion (Ni:Co:Mn=60:20:20), grind to control the D50 particle size ≤1μm, and further grind to control the D50 particle size ≤0.5μm to obtain the second material;

[0184] S3, Combine 4% of the first material obtained in step S1 and 96% of the second material obtained in step S2 in proportion.

[0185] A carbon source can be added in proportion or not, mixed evenly, ground, and dried after controlling the D50 particle size to ≤0.5μm to obtain precursor powder;

[0186] S4. The precursor powder obtained in step S3 is placed into a furnace with an atmosphere for the first sintering. The sintering temperature is 400℃~650℃ and the holding time is 4h~16h to obtain the first sintering product.

[0187] S5. The first sintering product obtained in step S4 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0188] Example 20

[0189] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 6% and the layered cathode material comprises 94% (this is a physical coating technology). Figure 1 As shown, the preparation method of this composite material is as follows:

[0190] S1. Weigh the lithium supplement precursor and lithium source according to the proportion, control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the first material;

[0191] S2. Weigh the layered cathode material precursor and lithium source in proportion (Ni:Co:Mn=60:20:20), grind to control the D50 particle size ≤1μm, and further grind to control the D50 particle size ≤0.5μm to obtain the second material;

[0192] S3. Mix the first material obtained in step S1 (6%) and the second material obtained in step S2 (94%) with a carbon source (optional) according to a certain ratio, grind them evenly, control the D50 particle size to ≤0.5μm, and then dry them to obtain the precursor powder.

[0193] S4. The precursor powder obtained in step S3 is placed into a furnace with an atmosphere for the first sintering. The sintering temperature is 400℃~650℃ and the holding time is 4h~16h to obtain the first sintering product.

[0194] S5. The first sintering product obtained in step S4 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0195] Example 21

[0196] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 8% and the layered cathode material comprises 92% (this is a physical coating technology). Figure 1 As shown, the preparation method of this composite material is as follows:

[0197] S1. Weigh the lithium supplement precursor and lithium source according to the proportion, control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the first material;

[0198] S2. Weigh the layered cathode material precursor and lithium source in proportion (Ni:Co:Mn=60:20:20), grind to control the D50 particle size ≤1μm, and further grind to control the D50 particle size ≤0.5μm to obtain the second material;

[0199] S3, combine the first material obtained in step S1 and the second material obtained in step S2 with...

[0200] A carbon source can be added in proportion or not, mixed evenly, ground, and dried after controlling the D50 particle size to ≤0.5μm to obtain precursor powder;

[0201] S4. The precursor powder obtained in step S3 is placed into a furnace with an atmosphere for the first sintering. The sintering temperature is 400℃~650℃ and the holding time is 4h~16h to obtain the first sintering product.

[0202] S5. The first sintering product obtained in step S4 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0203] Example 22

[0204] This embodiment provides a composite material containing a lithium supplement and a layered cathode material, wherein the lithium supplement comprises 4% and the layered cathode material comprises 96% (this is a physical coating technology). Figure 1 As shown, the preparation method of this composite material is as follows:

[0205] S1. Weigh the lithium supplement precursor and lithium source according to the proportion, control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the first material;

[0206] S2. Weigh the layered cathode material precursor and lithium source in proportion (Ni:Co:Al=80:15:5), grind to control the D50 particle size ≤1μm, and further grind to control the D50 particle size ≤0.5μm to obtain the second material;

[0207] S3. Mix the first material obtained in step S1 and the second material obtained in step S2 at a ratio of 4% and without adding carbon source, grind them evenly, control the D50 particle size to ≤0.5μm, and then dry them to obtain precursor powder.

[0208] S4. The precursor powder obtained in step S3 is placed into a furnace with an atmosphere for the first sintering. The sintering temperature is 400℃~650℃ and the holding time is 4h~16h to obtain the first sintering product.

[0209] S5. The product obtained in step S4 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina (4000 ppm) is added and mixed evenly. Then, a second sintering is carried out at a sintering temperature of 650℃~1300℃ for 8h~24h. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0210] Comparative Example 1

[0211] This embodiment provides a lithium supplement material, Li2NiO2, which is prepared by the following method:

[0212] S1. Weigh the layered cathode material precursor and lithium source according to the ratio, grind to control the D50 particle size ≤ 1 μm, and further grind to control the D50 particle size ≤ 0.5 μm;

[0213] S2. Add 2% glucose in proportion, mix evenly, grind, control D50 particle size ≤ 0.5μm, and then dry to obtain precursor powder;

[0214] S3. The precursor powder obtained in step S3 is placed in a furnace with an atmosphere for the first sintering. The sintering temperature is 400℃~650℃ and the holding time is 4h~16h to obtain the first sintering product.

[0215] S4. The first sintering product obtained in step S4 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina is added and mixed evenly before a second sintering is performed. The sintering temperature is 650℃~1300℃ and the temperature is maintained for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

[0216] Comparative Example 2

[0217] Commercially available layered lithium-ion battery cathode material NCM622, Ni:Mn:Co=6:2:2.

[0218] Comparative Example 3

[0219] Commercial layered oxide cathode material NCA, Ni:Co:Al = 80:15:5

[0220] Using the composite materials obtained in Examples 1-21 and Comparative Examples 1 and 2 as positive electrode lithium replenishment materials, the composite materials, carbon black conductive agent (SP) and binder polyvinylidene fluoride (PVDF) were mixed in a weight ratio of 8:1:1 under an environment with a dew point of -45°. Then, 120% of the weight of N-methylpyrrolidone (NMP) was added as a solvent, and the mixture was prepared into 2024 coin cells. The charging capacity was tested, and the charge-discharge range was 2.0V~4.4V with a charge-discharge rate of 0.01C. The test data are shown in Table 1 below.

[0221] Table 1 Test data of batteries made with different lithium supplements

[0222] LNO NCM622 C content Carbon coating thickness Charging capacity mAh / g Discharge capacity mAh / g Example 1 2 98 2% ≤15nm 218.26 194.86 Example 2 4 96 2% ≤15nm 223.52 193.72 Example 3 6 94 2% ≤15nm 228.78 192.58 Example 4 8 92 2% ≤15nm 234.04 191.44 Example 5 10 90 2% ≤15nm 239.3 190.3 Example 6 20 80 2% ≤15nm 265.6 184.6 Example 7 30 70 2% ≤15nm 291.9 178.9 Example 8 40 60 2% ≤15nm 318.2 173.2 Example 9 50 50 2% ≤15nm 344.5 167.5 Example 10 60 40 2% ≤15nm 370.8 161.8 Example 11 70 30 2% ≤15nm 397.1 156.1 Example 12 80 20 2% ≤15nm 423.4 150.4 Example 13 90 10 2% ≤15nm 449.7 144.7 Example 14 98 2 2% ≤15nm 218.26 194.86 Example 15 96 4 2% ≤15nm 223.52 193.72 Example 16 94 6 2% ≤15nm 228.78 192.58 Example 17 92 8 2% ≤15nm 454.96 143.56 Example 18 Physical Coating 2 98 2% ≤15nm 217.3 193.2 Example 19 Physical Coating 4 96 2% ≤15nm 221.9 193.2 Example 20 Physical Coating 6 94 2% ≤15nm 227.8 192.1 Example 21 Physical Coating 8 92 2% ≤15nm 233.5 191.2 Example 22 Physical coating NCA=80:15:5 4 96 0% 0 241.7 214.82 <![CDATA[Comparative Example 1 Li2NiO2]]> 100 0 2% ≤15nm 476.3 139.4 Comparative Example 2NCM622 0 100 0 0 213.1 196.2 Comparative example 3NCA=80:15:5 0 100 0 0 232.1 218.3

[0223] As can be seen from Table 1 above, the charging capacity decreases with the increase of ternary materials. This is because the charging capacity of the layered cathode NCM622 material itself is about 213.1 mAh / g and the discharge capacity is about 196.2 mAh / g, while the actual charging capacity of LNO is 476.3 mAh / g, but its discharge capacity is very low (about 139.4 mAh / g).

[0224] When the lithium replenisher content is low, this composite material can serve as a layered cathode composite material with its own lithium replenisher. From the in-situ coating of LNO with ternary cathode materials in Examples 1-5, it can be seen that as the LNO content increases, its charging capacity continuously increases, far exceeding the theoretical capacity of NCM622 itself, but its discharge capacity continuously decreases. In the same ratio but different preparation schemes (physical coating preparation schemes), Examples 18-21 with physical coating also show a similar trend to Examples 2-5. Different physical coatings, due to their slightly lower air stability compared to in-situ coating, result in slightly inferior performance compared to in-situ generated Examples 2-5.

[0225] In Examples 6-13, which serve as uniform lithium replenishers, it can be seen that the charging capacity increases while the discharging capacity decreases with increasing LNO content. In Example 6, with a lithium replenisher content of 20% and an NCM622 content of 80%, the composite material has a charging capacity of 265 mAh / g and a discharging capacity of 184 mAh / g. However, when the lithium replenisher content reaches 90%, the composite material has a charging capacity as high as 449.7 mAh / g, but a discharging capacity of only 144.7 mAh / g. This demonstrates that different application areas can be achieved by adjusting the ratio of LNO to NCM. With low LNO and high NCM content, it can serve as an active cathode material with its own lithium replenisher. With high LNO and low LFP content, the composite material can serve as a uniform lithium replenisher additive. On the other hand, physical coating has the same effect as in-situ coating, but due to the relatively poor uniformity of physical coating, its performance is slightly lower than that of the same proportion of in-situ coating.

[0226] In Example 22, an NCA coating scheme was also adopted, wherein Ni:Co:Al = 80:15:5.

[0227] According to Comparative Example 3, the uncoated NCA (80:15:5) has a charging capacity of up to 232 mAh / g and a discharging capacity of 218 mAh / g. The composite material using 96% NCA and 4% LNO physically coated has a charging capacity of 23...

[0228] Furthermore, it can be seen that the present invention obtains a composite material containing a lithium replenishing agent and a layered cathode material by adjusting the ratio of LNO and layered ternary material. With a high lithium replenishing agent content, it can serve as a high-capacity lithium replenishing additive; with a moderate lithium replenishing agent content, it can serve as a lithium replenishing additive with a suitable addition amount, suitable for uniform lithium replenishment, and improving the local lithium plating problem caused by uneven dispersion of high-capacity lithium replenishing agents. And with a low lithium replenishing agent content, it can serve as a cathode material containing a small amount of lithium replenishing agent.

[0229] In addition, lithium replenishment agents are mainly used to improve initial efficiency and the cycle performance of the cell; layered cathode materials, as the main active materials, can improve air stability when coated; carbon layers, which may or may not be present, mainly improve the electronic conductivity and air stability of the material; coating layers, which may or may not contain other elements, are mainly used to improve electrical performance and can also improve air stability to a certain extent.

[0230] The composite material containing lithium replenishing agent and layered positive electrode provided by the present invention is used in electrode sheets, batteries, battery packs and electrical devices, wherein the battery includes any one of lithium-ion batteries, solid-state batteries and semi-solid-state batteries.

[0231] The above embodiments are merely illustrative of the concept and technical solution of the present invention and are not intended to limit the present invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

[0232] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. This invention discloses a composite material containing a lithium replenishing agent and a layered cathode material. The material adopts a multilayer structure, which includes a lithium replenishing agent, an active material, and a layered cathode material. It may or may not contain a carbon coating layer and a coating layer containing or not containing elements other than carbon. The weight of the lithium replenishing agent is a + the weight of the active material is b = 100%; the weight of the carbon coating layer is c; and the weight of the coating layer containing elements other than carbon is d.

2. According to claim 1, the feature is that, The lithium replenishing agent has a mass percentage (a) of 0 ≤ a ≤ 100%; the lithium replenishing agent can be lithium nickel oxide, lithium iron oxide, lithium cobalt oxide, lithium aluminum oxide, lithium manganese oxide, Li3N, Li2S, Li2S / KB / PVP, Li2S / Co, LiF / Co, Li2O2, Li2C4O4, Li2C2O4, or a combination of one or more of these.

3. According to claim 1, the feature is that, The main active material is a layered cathode material, with the layered cathode material accounting for 0% ≤ 100% of the total material weight. The layered cathode material can be a ternary material (any proportion of monocrystalline or polycrystalline NCM or NCA, or a multi-element material modified with ternary materials as the main structural component), lithium cobalt oxide cathode material, or cobalt-free layered cathode material; among them, the layered ternary cathode material has the structural formula LiNi. x Co y M 1-x-y O 2， Where M is at least one of Mn, Al, W, Zr, Mg, B, Nb, Ta, Mo, La, and Ti, 0.33≤x≤1, 0≤y≤0.33; the structural formula of the ternary material modified with the main structure is LiNi x Co y M z N 1-x-y-z O2, wherein M is at least one of Mn, Al, W, Zr, Mg, B, Nb, Ta, Mo, La and Ti, 0.33≤x≤1, 0≤y≤0.33, 0≤z≤0.33, and N is Mn, Al, W, Zr, Mg, B, Nb, Ta, Mo, La and Ti, and M and N do not belong to the same element at the same time.

4. According to claim 1, the feature is that, The carbon coating layer comprises an inorganic carbon source and / or an organic carbon source and / or an organic gas coating layer, wherein the carbon mass percentage of the total material weight is 0% ≤ 10%; the coating layer thickness is 0 nm ≤ carbon layer thickness ≤ 100 nm; the inorganic carbon source comprises at least one or a combination of two or more of carbon nanotubes, graphene, graphite, fullerene, VGCF, amorphous carbon, soft carbon, and hard carbon; the organic carbon source comprises one or a combination of two or more of glucose, hydroxymethyl cellulose, sucrose, starch, PEG, PEO, cellulose, petroleum, asphalt, and PVP; the organic gas carbon source comprises chain alkanes (C n H 2n +2 (where n ≥ 1), for example, methane (CH4), ethane (C2H6), propane (C3H8), etc.), cyclic alkanes: general formula is C n H 2n (where n ≥ 3), for example, cyclopropane (C3H6), cyclohexane (C6H6) 12 ) etc., the general formula for alkenes is C n H 2n (where n ≥ 2), for example, ethylene (C2H4), propylene (C3H6), butene (C4H8), etc.; olefins The molecule contains a carbon-carbon double bond; the general formula for alkynes is C1. n H 2n -2 (where n ≥ 2), such as acetylene (C2H2), propyne (C3H4), butyne (C4H6), etc. Alkyne molecules contain carbon-carbon triple bonds and can be one or more of the above.

5. According to claim 1, the coating layer may or may not contain elements other than carbon, for improving the material's performance. The coating layer thickness may be 0 nm ≤ coating thickness ≤ 50 nm; 0 ≤ d; the coating amount accounts for ≤ 1% of the total material mass; the coating elements may include one or more of the following composite elements: B, N, Mg, Al, F, Si, P, S, K, Ca, Sc, V, Ti, Cr, Mn, Ni, Ga, Ge, La, Se, Rb, Sr, Y, Nb, Mo, Ru, Eu, Er, Yb, Dy, Cs, Sb, Sn, Se, Te, Bi, Zn, Cu, Ce, Rh, Tb, Lu, Hf, Ta, W, Os, Ir, Pt, Au, Pb, Zr, Cd, Pd, Ag, etc.

6. This invention also discloses a method for preparing a composite material containing a lithium supplement and a layered cathode material, characterized in that, The first method includes the following steps: S1. Preparation of lithium supplement precursor: Weigh a nickel source, dissolve it in deionized water, and prepare a solution of a certain concentration; add a precipitant and a complexing agent, and after a period of reaction, obtain hydroxide, wash and dry to obtain lithium supplement precursor; S2. Preparation of layered cathode material precursor: Prepare nickel salt, cobalt salt, manganese salt or aluminum salt solution, mix the nickel salt, cobalt salt, manganese salt or aluminum salt solution evenly, uniformly disperse the above S1 lithium supplementation agent precursor in the layered cathode precursor solution, add the precipitant solution, complexing agent and the mixture together in a reaction vessel for reaction and precipitation, and allow to stand for aging after sufficient reaction; perform solid-liquid separation and washing on the aged solution; S3, Preparation of composite material containing lithium supplementation agent and layered cathode: S2 precursor is thoroughly mixed with lithium source and carbon source (which may be added in proportion or not) and sintered under atmospheric conditions. S4. The first sintering product obtained in step S3 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent alumina is added and mixed evenly before a second sintering is performed. The sintering temperature is 650℃~1300℃ and the temperature is maintained for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

7. The steps of the second physical preparation method are as follows: S1. Weigh the lithium supplement precursor and lithium source according to the proportion, control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the first material; S2. Weigh the layered cathode material precursor and lithium source according to the ratio, grind to control the D50 particle size ≤ 1μm, and further grind to control the D50 particle size ≤ 0.5μm to obtain the second material; S3. The first material obtained in step S1 and the second material obtained in step S2 are mixed evenly with carbon source (which may be added proportionally or not), ground, and dried after controlling the D50 particle size to ≤0.5μm to obtain precursor powder. S4. The precursor powder obtained in step S3 is placed into a furnace with an atmosphere for the first sintering. The sintering temperature is 400℃~650℃ and the holding time is 4h~16h to obtain the first sintering product. S5. The first sintering product obtained in step S4 is pulverized to a D50 particle size ≤ 40 μm. A small amount of surface coating agent is added and mixed evenly before a second sintering is performed. The sintering temperature is 650℃~1300℃ and the temperature is maintained for 8h~24h. The second sintering product can be subjected to CVD deposition treatment or not. Finally, the product is pulverized, graded, demagnetized, and packaged to obtain the desired product.

8. The preparation method according to claim 6, characterized in that, The nickel source includes one or more of nickel carbonate, nickel hydroxide, nickel nitrate, nickel sulfate, nickel oxide, nickel greening, nickel oxalate, nickel acetate, nickel citrate, and nickel sulfate; the concentration of the lithium replenishing agent precursor is 0 ≤ lithium replenishing agent precursor concentration ≤ 50 mol / L.

9. The precipitant solution is a sodium hydroxide solution or lithium hydroxide solution with a mass concentration of 5% to 60%, the complexing agent solution is an ammonia solution with a mass concentration of 5% to 60%, and the molar ratio of Li:Ni in the lithium supplement precursor is in the range of 1.9 ≤ Li / Ni ≤ 2.

2.

10. The preparation method according to claim 6, characterized in that, A solution of nickel salt, cobalt salt, manganese salt or aluminum salt, wherein the nickel salt, cobalt salt, manganese salt or aluminum salt is at least one or a combination of multiple sulfates, nitrates, acetates or halogens.

11. The preparation method according to claim 6, characterized in that, The lithium source includes one or a combination of two or more of lithium carbonate, lithium oxide, lithium hydroxide, lithium acetate, lithium citrate, lithium oxalate, and lithium adipate.

12. The preparation method according to claim 6, characterized in that, The ratio of the lithium replenishing agent precursor to the layered material precursor is equal to the mol of the lithium replenishing agent and the ternary material in the final product. The mol ratio of the added ternary precursor to lithium is in the range of 0.9 ≤ Li : (x+y+z) = 1.

1.

13. The preparation method according to claim 6, characterized in that, The reaction time t1 is 0 ≤ t1 ≤ 48h; the drying process adopts any one of spray drying, flash drying, and centrifugal drying; in step S4, the atmosphere is one or a combination of two or more of oxygen, nitrogen, argon, and air.

14. The preparation method according to claim 6, characterized in that, The CVD deposition process is carried out at a temperature of 700℃ to 900℃ for 2 hours to 16 hours.

15. The application of a composite material containing a lithium replenishing agent and a layered cathode material according to claim 1, or a lithium replenishing agent prepared by any one of claims 1 to 14, in electrode sheets, batteries, battery packs, and electrical devices, wherein the battery includes any one of lithium-ion batteries, solid-state batteries, and semi-solid-state batteries.

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