Method for manufacturing positive electrode particles coated with ceramic particles and glass-phase continuous layer by applying wet-type one-time sintering process

Abstract

The invention discloses a method for manufacturing positive electrode particles coated with ceramic particles and a glass-phase continuous layer by applying a wet-type one-time sintering process, which comprises the following steps of: mixing and grinding a lithium source, a glass-phase precursor, an LLZO precursor and a dispersion liquid in a mixer to form first precursor slurry, putting a nickel-cobalt-manganese precursor into the first precursor slurry, and fully stirring and mixing to form second precursor slurry; fully stirring and mixing the second precursor slurry, and drying to obtain precursor powder; carrying out aerobic sintering on the precursor powder, wherein the lithium source is firstly melted to react with each nickel cobalt manganese precursor and each LLZO precursor to respectively form a plurality of NCM (nickel cobalt lithium manganate) particles and a plurality of LLZO particles; the glass phase precursor forms a glass phase layer to coat the outer surface of each NCM particle, and the plurality of LLZO particles are distributed in each glass phase layer to integrally form the plurality of positive electrode particles.

Description

Technical Field

[0001] This invention relates to the field of cathode material technology, and in particular to a method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process. Background Technology

[0002] A battery is mainly formed by a positive electrode and a negative electrode placed in an electrolyte. The positive electrode is formed by mixing and dispersing numerous positive electrode conductive units (positive electrode materials, such as lithium cobalt oxide) in a slurry. To increase conductivity, multiple positive electrode particles are filled into the positive electrode slurry. The material of these positive electrode particles can be selected from NCM (lithium nickel cobalt manganese oxide) or a mixture containing NCM.

[0003] However, in conventional technologies, the interface of the cathode particles is prone to side reactions, leading to a decrease in cathode lifespan and low electronic conductivity, resulting in poor overall battery performance. Therefore, conventional technologies further coat the cathode particles with ceramic particles such as LLZO (lithium lanthanum zirconium oxide) to increase lithium-ion conductivity, and coat the cathode particles with a glass phase layer to reduce interfacial impedance, improve powder coating properties, stabilize them in the electrolyte, and prevent interfacial side reactions. To further increase the conductivity of the slurry, carbon nanotubes and nanoscale amorphous carbon can also be added to coat the cathode particles.

[0004] The conventional method for manufacturing NCM composite cathode particles coated with ceramic particles and a glass phase layer employs a two-stage sintering process. In this process, precursors are used to pre-form NCM particles and ceramic particles, respectively. The NCM particles are then sintered with the glass phase material, resulting in a glass phase layer coating the surface of the NCM particles. Finally, the ceramic particles are mixed and stirred with the NCM particles containing the glass phase layer to form the composite cathode particle. However, this method requires two stages of sintering, which incurs significant costs and time, leading to increased manufacturing costs.

[0005] Therefore, existing technologies have shortcomings and need to be improved. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process. The cathode particles coated with glass phase and ceramic particles are formed by wet and one-time sintering, thereby improving production efficiency and reducing time costs.

[0007] Therefore, the purpose of this case is to solve the aforementioned problems in the prior art. This case proposes a method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process. This method employs a wet mixing approach, that is, by adding a dispersion liquid, the lithium source, the glass phase precursor, the LLZO precursor, and the nickel-cobalt-manganese precursor are uniformly dispersed in the solution. Therefore, the overall uniformity is better, and the deposition layer formed by the glass phase precursor and the LLZO precursor on the surface of the nickel-cobalt-manganese precursor is denser, thus forming a more complete glass phase layer and LLZO particles. This glass phase layer can prevent direct contact between the NCM particles and the electrolyte, reducing interfacial side reactions and lowering the interfacial resistance for lithium ions to enter and exit the NCM particles. The LLZO particles have the ability to accommodate and homogenize lithium ions and can disperse the lithium ion pathway, thus providing better lithium ion transport. This invention utilizes a single sintering process to form the cathode particle from NCM precursor, glass phase precursor, and LLZO precursor, reducing process complexity, processing time, and production costs. The cathode particle is further coated with carbon nanotubes and nanoscale amorphous carbon, increasing electron conductivity. The cathode with this cathode particle can then serve as a ternary cathode.

[0008] To achieve the above objectives, this invention proposes a method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process. These cathode particles are used as the cathode material in solid-state or near-solid-state batteries. The method includes the following steps: Step A: A lithium source, a glass phase precursor, an LLZO precursor, and a dispersion are placed in a mixer for mixing and grinding to form a first precursor slurry. The particle size of the first precursor slurry is ground to a D50 particle size (mass-median diameter, MMD) < 200 nm. The glass phase precursor is used to form the glass phase layer; the LLZO precursor is used to form LLZO. ZO is used to form the ceramic particles; Step B: Add the nickel-cobalt-manganese precursor to the first precursor slurry in the mixer and mix thoroughly to form a second precursor slurry; wherein the nickel-cobalt-manganese precursor is a precursor for forming NCM (lithium nickel cobalt manganese oxide); the nickel-cobalt-manganese precursor is a granular material formed by multiple particles, and the particle surface of the nickel-cobalt-manganese precursor has multiple pores; Step C: Dry the second precursor slurry to obtain precursor powder; wherein the drying is carried out by one of the following methods: vacuum baking, reduced pressure concentration, and spray drying to quickly remove liquid, so that the glass phase precursor and the LLZO precursor precipitate from the particle surface of the nickel-cobalt-manganese precursor to form a deposition layer deposited on the particles of the nickel-cobalt-manganese precursor. The precursor powder with a uniform and dense deposition layer is generated on the particle surface; wherein the glass phase precursor and the LLZO precursor are distributed in a continuous thin film distribution or a discontinuous distribution with island-like particles on the particle surface of the nickel-cobalt-manganese precursor; Step D: The precursor powder is placed in a sintering furnace for aerobic sintering to obtain sintered powder formed by multiple positive electrode particles; wherein the melting point of the lithium source is lower than that of the nickel-cobalt-manganese precursor, the glass phase precursor and the LLZO precursor, so that the lithium source will melt first in the high temperature of aerobic sintering and mix into the deposition layer of the precursor powder, and enter the multiple pores of the nickel-cobalt-manganese precursor; then the lithium source will decompose into highly reactive lithium oxide, which... The oxide reacts with the nickel-cobalt-manganese precursor to form multiple NCM (lithium nickel cobalt-manganese oxide) particles; simultaneously, the lithium oxide also reacts with the LLZO precursor to form multiple LLZO particles; then, when the glass phase precursor melts, a glass phase layer is formed to coat the outer surface of each NCM particle, and the multiple LLZO particles are distributed inside or on the outer surface of the corresponding glass phase layer. The NCM particles with the glass phase layer and the corresponding LLZO particles form the corresponding positive electrode particles; wherein the glass phase layer is used to prevent direct contact between the NCM particles and the electrolyte, reduce interfacial side reactions, and reduce the interfacial impedance for lithium ions to enter and exit the NCM particles, thereby improving the rate charge and discharge performance and accommodating the volume changes during charge and discharge.

[0009] The features and advantages of this work will be further explained in the following description; please refer to the accompanying drawings while reading. Attached Figure Description

[0010] Figure 1 The diagram shows steps 500 to 530 of the process for manufacturing the cathode particles in this case.

[0011] Figure 2 The flowchart shows steps 500 to 530 of manufacturing the cathode particles in this case.

[0012] Figure 3 This diagram shows the steps involved in manufacturing the carbon-coated cathode particles in this case.

[0013] Figure 4 This shows an enlarged view of the structure of the positive electrode particles in this case.

[0014] Figure 5 This shows a cross-sectional view of the positive electrode particles in this case.

[0015] Figure 6 This example demonstrates the application of this case.

[0016] Figure 7 This diagram shows the structure of the carbon-coated cathode particles in this case.

[0017] Figure 8 This diagram shows the structure of the nickel-cobalt-manganese precursor in this case.

[0018] Figure 9 This diagram shows a cross-sectional view of the nickel-cobalt-manganese precursor and the deposited layer in this case.

[0019] The components include: a positive electrode substrate 10, a positive electrode slurry layer 12, a positive electrode slurry 14, a nickel-cobalt-manganese precursor 20, a pore 21, a lithium source 22, a glass phase precursor 24, a dispersion 25, an LLZO precursor 26, a first precursor slurry 28, a second precursor slurry 29, carbon nanotubes 30, precursor powder 31, short-chain carbon nanotubes 32, long-chain carbon nanotubes 34, nanoscale amorphous carbon 35, sintered powder 40, a deposition layer 51, a positive electrode 100, a mixer 150, positive electrode particles 200, NCM particles 201, a glass phase layer 241, a sintering furnace 250, LLZO particles 261, and carbon-coated positive electrode particles 300. Detailed Implementation

[0020] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0021] Please refer to Figures 1 to 9 As shown, this case proposes a method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process. Figure 6 As shown, the positive electrode particles 200 of this invention are mainly used in the positive electrode 100 of general solid-state or solid-state batteries. The positive electrode 100 includes a positive electrode substrate 10 and a positive electrode slurry layer 12 coated on the positive electrode substrate 10. The positive electrode slurry layer 12 includes a positive electrode slurry 14 with a binder and a plurality of positive electrode particles 200. The binder is such as PVDF (polyvinylidene fluoride), PEO (polyethylene oxide), etc. The plurality of positive electrode particles 200 account for 80 wt% to 98 wt% of the weight percentage of the positive electrode slurry layer 12.

[0022] like Figure 1 As shown, the method in this case includes the following steps: Step 500: The lithium source 22, glass phase precursor 24, LLZO precursor 26, and dispersion 25 are placed in a mixer 150 and mixed to form a first precursor slurry 28. The particle size of the first precursor slurry 28 is then ground to a D50 particle size (mass-median-diameter, MMD, the mass median particle size distribution) < 200 nm. The solids formed by the lithium source 22, the glass phase precursor 24, and the LLZO precursor 26 account for 5 wt% to 25 wt% of the weight of the first precursor slurry 28. The glass phase precursor 24 is a precursor for forming a glass phase layer; the LLZO precursor 26 is a precursor for forming LLZO, which is used to form the ceramic particles of this invention.

[0023] The lithium source 22 is selected from at least one of lithium hydroxide (LiOH), lithium carbonate (Li2CO3), lithium nitrate (LiNO3), or a mixture thereof.

[0024] The dispersion 25 is such as an alcohol solution or pure water, preferably the alcohol solution is selected from ethanol or isopropanol.

[0025] The glass precursor 24 is an amorphous oxide, specifically an amorphous oxide whose lithium-ion conductivity can exceed 10⁻⁵ S / cm after heat treatment. This amorphous oxide is an oxide of lithium with elements from Group IIIA, IVA, or VA, or an amorphous oxide-based solid electrolyte. Examples of such oxides include Li₂O-RO. nWhere n = 1~3, and R is at least one of boron (B), aluminum (Al), silicon (Si), germanium (Ge), phosphorus (P), and arsenic (As). The amorphous oxide-based solid electrolyte is selected from amorphous perovskite-based solid electrolytes (Li-La-Ti-O, LLTO) and garnet-based solid electrolytes (e.g., Li7La3Zr2O). 12 It includes at least one of LLZO, lithium phosphorus oxynitride (LiPON), and lithium titanium aluminum phosphate (LATP).

[0026] The LLZO precursor 26 is a granular material formed by multiple particles. In this case, the LLZO precursor 26 refers to all garnet solid electrolytes (such as Li7La3Zr2O) that can form a cubic crystal system (a crystal structure with a specific morphology) after co-firing with the lithium source 22. 12 The specific components of the product include oxides, hydroxides, carbonates, etc. The intermediate product formed after the specific components are coprecipitated or sintered has a structure with a distinct crystalline phase or a multi-component mixed amorphous structure.

[0027] The particle size of the LLZO precursor 26 is between 20 nm and 200 nm. When this LLZO precursor 26 is used to form the LLZO Li7La3Zr2O... 12 In this case, the LLZO precursor 26 comprises a lithium source compound (selected from lithium oxide, lithium hydroxide, lithium carbonate, etc.), a lanthanum source compound (selected from lanthanum oxide, lanthanum hydroxide, lanthanum carbonate, etc.), and a zirconium source compound (selected from zirconium oxide, zirconium hydroxide, zirconium carbonate, etc.). The LLZO precursor 26 may also contain doping elements, such as aluminum (Al), gallium (Ga), tantalum (Ta), niobium (Nb), copper (Cu), etc., with the doping element content in an equivalent ratio to lanthanum (La) not exceeding 0.25:3.

[0028] Step 510: Add the nickel-cobalt-manganese precursor 20 to the first precursor slurry 28 in the mixer 150 and mix thoroughly to form the second precursor slurry 29. The nickel-cobalt-manganese precursor 20 is a precursor for forming NCM (lithium nickel cobalt manganese oxide).

[0029] In the second precursor slurry 29, the molar equivalent ratio of the nickel-cobalt-manganese precursor 20, the lithium source 22, the glass phase precursor 24, and the LLZO precursor 26 is 1.0:(1.02~1.25):(0.005~0.02):(0.005~0.02).

[0030] In the second precursor slurry 29, the solids formed by the lithium source 22, the glass phase precursor 24, the LLZO precursor 26, and the nickel-cobalt-manganese precursor 20 account for a weight percentage between 15 wt% and 40 wt% of the second precursor slurry 29. The ratio of the weight of the nickel-cobalt-manganese precursor 20 to the total weight of the glass phase precursor 24 and the LLZO precursor 26 is greater than 20:1.

[0031] like Figure 8 As shown, the nickel-cobalt-manganese precursor 20 is a granular material formed by multiple particles, and the surface of the particles of the nickel-cobalt-manganese precursor 20 has multiple pores 21. The particle size of the nickel-cobalt-manganese precursor 20 is between 1 micrometer and 5 micrometers. Preferably, the nickel-cobalt-manganese precursor 20 is a porous spherical nickel-cobalt-manganese precursor composed of needle-like grains, such as Ni x Mn y Co z (OH)2, where x>0.8, x+y+z=1. Step 520: The second precursor slurry 29 is dried to obtain precursor powder 31. The drying method is selected from rapid liquid removal methods such as vacuum baking, reduced pressure concentration, and spray drying, causing the glass phase precursor 24 and the LLZO precursor 26 to precipitate from the particle surface of the nickel-cobalt-manganese precursor 20, forming a deposition layer 51 deposited on the particle surface of the nickel-cobalt-manganese precursor 20 (e.g., ...). Figure 9 As shown), a precursor powder 31 with a uniform and dense deposition layer 51 is produced.

[0032] In step 510, a buffer solution (such as ammonia or acetic acid) may be added to control the thickness and density of the deposition layer 51 formed by the glass phase precursor 24 and the LLZO precursor 26.

[0033] In step 500, the dispersion 25 is added for mixing, which is wet mixing. This allows the lithium source 22, the glass phase precursor 24, the LLZO precursor 26, and the nickel-cobalt-manganese precursor 20 to be uniformly dispersed in the dispersion 25, achieving better mixing uniformity. It also makes the deposition layer 51 formed by the glass phase precursor 24 and the LLZO precursor 26 more dense.

[0034] The glass phase precursor 24 and the LLZO precursor 26 are distributed in a continuous thin film distribution pattern or a discontinuous distribution pattern with island-shaped particles on the particle surface of the nickel-cobalt-manganese precursor 20.

[0035] Step 530: The precursor powder 31 is placed in a sintering furnace 250 for aerobic sintering. First, the temperature is raised to 400°C to 700°C in a pure oxygen atmosphere and maintained for 1 to 4 hours, so that the lithium source 22 in the precursor powder 31 is completely melted and fully mixed with other substances in the precursor powder 31. Then, the temperature is raised to 800°C to 1000°C and maintained for 6 to 12 hours. Finally, the temperature is naturally cooled to room temperature in a pure oxygen atmosphere to obtain sintered powder 40 formed by multiple positive electrode particles 200.

[0036] like Figure 4 and Figure 5 As shown, the lithium source 22 has a lower melting point than the nickel-cobalt-manganese precursor 20, the glassy precursor 24, and the LLZO precursor 26. Therefore, it will melt first and mix into the deposited layer of the precursor powder 31, and enter the multiple pores 21 of the nickel-cobalt-manganese precursor 20. Then, the lithium source 22 decomposes into highly reactive lithium oxide at high temperature. The lithium oxide reacts with the nickel-cobalt-manganese precursor 20 to form multiple NCM (lithium nickel cobalt manganese oxide) particles 201. At the same time, the lithium oxide also reacts with the LLZO precursor 26 to form multiple LLZO particles 261. On the other hand, when the glass phase precursor 24 melts at high temperature, a glass phase layer 241 is formed and covers the outer surface of each NCM particle 201. The plurality of LLZO particles 261 are distributed inside or on the outer surface of the corresponding glass phase layer 241. The NCM particle 201 having the glass phase layer 241 and the corresponding LLZO particles 261 forms the corresponding positive electrode particle 200.

[0037] The crystal structure of the glass phase layer 241 does not have a specific form, and the glass phase layer 241 is a continuous thin film layer covering the outer surface of the NCM particle 201.

[0038] The glass phase layer 241 is used to block the direct contact between the NCM particles 201 and the electrolyte, reducing interfacial side reactions; at the same time, it reduces the interfacial impedance of lithium ions entering and leaving the NCM particles 201, improving the rate charge and discharge performance. The glass phase layer 241 can accommodate the volume change during charge and discharge, improving the mechanical properties of the powder and reducing breakage.

[0039] like Figure 3 As shown, this case also includes the following steps: Step 540: The sintered powder 40 is mechanically pulverized and then sieved through a screen, preferably with a mesh size of 500. After sieving, the D50 particle size of the NCM particles 201 is 2 to 10 micrometers; the thickness of the glass phase layer 241 is between 5 nanometers and 100 nanometers. The maximum radial dimension of the LLZO particles 261 is less than 80 nanometers.

[0040] Following step 540, steps 550A or 550B are applied to mix multiple carbon nanotubes 30 (CNTs) and multiple nanoscale amorphous carbon 35 with the sieved sintered powder 40 to form multiple carbon-coated cathode particles 300. Steps 550A and 550B achieve this carbon material mixing using different methods, which are explained below.

[0041] Step 550A: The sintered powder 40, the plurality of carbon nanotubes 30, and the plurality of nanoscale amorphous carbon 35 are simultaneously placed into a dry stirrer (such as a planetary stirrer or a drum stirrer, not shown in the figure) for mixing to form the plurality of carbon-coated cathode particles 300. Each carbon-coated cathode particle 300 includes a corresponding cathode particle 200, a corresponding plurality of carbon nanotubes 30, and a plurality of nanoscale amorphous carbon 35 coating the exterior of the corresponding cathode particle 200 (such as...). Figure 7 The dry mixer has a mixing speed of 50 rpm to 500 rpm and a mixing time of 2 hours to 8 hours.

[0042] Step 550B: The plurality of carbon nanotubes 30 and the sintered powder 40 are mixed for the first time, and then the plurality of nanoscale amorphous carbon 35 are added for the second mixing to form the positive electrode particles 300 coated with carbon material. Each positive electrode particle 300 coated with carbon material includes a corresponding positive electrode particle 200, a corresponding plurality of carbon nanotubes 30, and a plurality of nanoscale amorphous carbon 35 coating the outside of the corresponding positive electrode particle 200. The first and second mixing methods are dry ball milling or wet ball milling.

[0043] The plurality of carbon nanotubes 30 include a plurality of short-chain carbon nanotubes 32 and a plurality of long-chain carbon nanotubes 34. The length of each short-chain carbon nanotube 32 is between 0.5 micrometers and 1 micrometer, and the length of each long-chain carbon nanotube 34 is between 3 micrometers and 8 micrometers. In each of the positive electrode particles 300 coated with carbon material, the weight percentage of the corresponding plurality of carbon nanotubes 30 in the corresponding positive electrode particle 200 is between 0.1 wt% and 2 wt%.

[0044] The short-chain carbon nanotubes 32 are used to bridge each LLZO particle 261 and the corresponding cathode particle 200, while the long-chain carbon nanotubes 34 are used to coat each cathode particle 200. The nanoscale amorphous carbon 35 is, for example, the amorphous carbon of the Super P conductive agent. The size of each nanoscale amorphous carbon 35 is between 20 nanometers and 100 nanometers. Each nanoscale amorphous carbon 35 fills the gaps formed by the interlacing of the plurality of carbon nanotubes 30. In each cathode particle 300 coated with carbon material, the total weight of the corresponding plurality of nanoscale amorphous carbon 35 accounts for between 0.1 wt% and 2 wt% of the weight of the corresponding cathode particle 200.

[0045] Carbon nanotubes are used to increase electronic conductivity by forming conductive bridges around the various LLZO particles 261, allowing electrons to conduct across the positive electrode particles 200. The carbon nanotubes 30 are randomly distributed on the surface of their respective positive electrode particles 200. Because carbon nanotubes have extremely high conductivity, electrons can conduct between the different LLZO particles 261 and the positive electrode particles 200 via the carbon nanotubes 30, thus increasing the overall conductivity of the positive electrode 100.

[0046] The multiple nanoscale amorphous carbon 35 and the multiple carbon nanotubes 30 both serve as conductive agents. Because each nanoscale amorphous carbon 35 is in the form of particles, while each carbon nanotube 30 is in the form of elongated strips, gaps will be formed between the multiple carbon nanotubes 30 crisscrossing on the positive electrode particle 200. These gaps cannot conduct current. Therefore, by adding the corresponding nanoscale amorphous carbon 35 into these gaps, the charge can be conducted between different carbon nanotubes 30 through the bridging of the nanoscale amorphous carbon 35, further increasing the current transfer efficiency.

[0047] The advantages of this invention are the use of a wet mixing method, where the lithium source, glass phase precursor, LLZO precursor, and nickel-cobalt-manganese precursor are uniformly dispersed in the solution by adding a dispersion liquid. This results in better overall uniformity, and the deposition layer formed by the glass phase precursor and LLZO precursor on the surface of the nickel-cobalt-manganese precursor is denser, thus forming a more complete glass phase layer and LLZO particles. This glass phase layer can prevent direct contact between the NCM particles and the electrolyte, reducing interfacial side reactions and lowering the interfacial resistance for lithium ions to enter and exit the NCM particles. The LLZO particles have the ability to accommodate and homogenize lithium ions and can disperse the lithium ion pathway, providing better lithium ion flow. This invention uses a single sintering process to form the cathode particles from the NCM precursor, glass phase precursor, and LLZO precursor, reducing process complexity, processing time, and production costs. The cathode particle is further coated with carbon nanotubes and nanoscale amorphous carbon, which can increase the electron conduction efficiency of the cathode particle. The cathode with the cathode particle of this invention can be used as a ternary cathode.

[0048] The above detailed description is a specific description of a feasible embodiment of this case. However, this embodiment is not intended to limit the scope of the patent in this case. All equivalent implementations or modifications that do not depart from the spirit of the technology in this case should be included in the scope of the patent in this case.

Claims

1. A method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process, characterized in that, The positive electrode particle is used as the positive electrode in a solid-state or solid-state-like battery, and the method includes the following steps: Step A: The lithium source, glass phase precursor, LLZO precursor, and dispersion are placed in a mixer for mixing and grinding to form a first precursor slurry. The particle size of the first precursor slurry is ground to a D50 particle size of < 200 nm. The glass phase precursor is used to form the glass phase layer. The LLZO precursor is used to form LLZO, which is used to form the ceramic particles. LLZO is a lithium lanthanum zirconium oxide compound. Step B: Add the nickel-cobalt-manganese precursor to the first precursor slurry in the mixer and mix thoroughly to form a second precursor slurry; wherein the nickel-cobalt-manganese precursor is a precursor for forming NCM; the nickel-cobalt-manganese precursor is a granular material formed by multiple particles, and the surface of the nickel-cobalt-manganese precursor particles has multiple pores; wherein, NCM is lithium nickel cobalt manganese oxide; Step C: The second precursor slurry is dried to obtain precursor powder; wherein the drying is carried out by one of the following methods: vacuum baking, reduced pressure concentration, and spray drying to quickly remove liquid, so that the glass phase precursor and the LLZO precursor precipitate from the particle surface of the nickel cobalt manganese precursor to form a deposition layer deposited on the particle surface of the nickel cobalt manganese precursor, thereby producing precursor powder with a uniform and dense deposition layer. The glass phase precursor and the LLZO precursor are distributed in a continuous thin film distribution pattern or a discontinuous distribution pattern with island-shaped particles on the particle surface of the nickel-cobalt-manganese precursor. Step D: The precursor powder is placed in a sintering furnace for aerobic sintering to obtain sintered powder formed by multiple cathode particles. The melting point of the lithium source is lower than that of the nickel-cobalt-manganese precursor, the glass phase precursor, and the LLZO precursor, so that the lithium source will melt first in the high temperature of aerobic sintering and mix into the deposition layer of the precursor powder, and enter the multiple pores of the nickel-cobalt-manganese precursor. Then the lithium source will decompose into highly reactive lithium oxide, which reacts with the nickel-cobalt-manganese precursor to form multiple NCM particles. At the same time, the lithium oxide will also react with the LLZO precursor to form multiple LLZO particles. Then, when the glass phase precursor melts, a glass phase layer is formed to coat the outer surface of each NCM particle, and the multiple LLZO particles are distributed inside or on the outer surface of the corresponding glass phase layer. The NCM particles with the glass phase layer and the corresponding LLZO particles form the corresponding cathode particles. The glass phase layer is used to block direct contact between the NCM particles and the electrolyte, reduce interfacial side reactions, and reduce the interfacial impedance of lithium ions entering and leaving the NCM particles, thereby improving the rate charge and discharge performance and accommodating volume changes during charge and discharge.

2. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that, In the first precursor slurry, the solids formed by the lithium source, the glass phase precursor and the LLZO precursor account for a proportion of 5wt% to 25wt% of the first precursor slurry. In the second precursor slurry, the solids formed by the lithium source, the glass phase precursor, the LLZO precursor, and the nickel-cobalt-manganese precursor account for 15 wt% to 40 wt% of the weight of the second precursor slurry; and The ratio of "the weight of the nickel-cobalt-manganese precursor" to "the total weight of the glass phase precursor and the LLZO precursor" is greater than 20:

1.

3. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that... The dispersion is an alcohol solution or pure water.

4. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that... In step C, a buffer solution is added to control the thickness and density of the deposition layer formed by the glass phase precursor and the LLZO precursor.

5. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 4, characterized in that... The buffer solution is either ammonia or acetic acid.

6. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that, In the second precursor slurry, the molar equivalent ratio of the nickel-cobalt-manganese precursor, the lithium source, the glass phase precursor, and the LLZO precursor is 1.0:(1.02~1.25):(0.005~0.02):(0.005~0.02).

7. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that, The particle size of the nickel-cobalt-manganese precursor is between 1 micrometer and 5 micrometers; the particle size of the LLZO precursor is between 20 nm and 200 nm.

8. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that... The nickel-cobalt-manganese precursor is a porous spherical nickel-cobalt-manganese precursor composed of needle-like grains.

9. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that, The nickel-cobalt-manganese precursor is Ni x Mn y Co z (OH)2, x>0.8, x+y+z=1.

10. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that, The lithium source is selected from at least one of lithium hydroxide, lithium carbonate, lithium nitrate, or a mixture thereof.

11. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that, The glass phase precursor is an amorphous oxide, which, after heat treatment, exhibits a lithium-ion conductivity higher than 10. -5 S / cm non-crystalline oxide; wherein the crystal structure of the glass phase layer does not have a specific morphology, and the glass phase layer is a continuous thin film layer covering the outer surface of the NCM particles.

12. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 11, characterized in that, The non-crystalline oxide or non-oxide solid electrolyte is an oxide of lithium with elements of group IIIA, IVA, and VA.

13. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 12, characterized in that, The oxide system of this lithium with elements of Group IIIA, IVA, and VA is Li₂O-RO. n , where R is at least one of boron, aluminum, silicon, germanium, phosphorus, and arsenic, and n = 1 to 3.

14. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 11, characterized in that, The non-crystalline oxide is an amorphous oxide-based solid electrolyte.

15. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 14, characterized in that... The amorphous oxide-based solid electrolyte is selected from at least one of the following: amorphous perovskite-based solid electrolyte, garnet-based solid electrolyte, lithium-phosphorus-oxy-nitride, or lithium titanium aluminum phosphate; wherein lithium-phosphorus-oxy-nitride is abbreviated as LiPON, and lithium titanium aluminum phosphate is abbreviated as LATP.

16. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that, The LLZO precursor is a specific component of all garnet solid electrolytes that form a cubic crystal system after co-firing with the lithium source. The specific component includes at least one of oxides, hydroxides, and carbonates. The intermediate product formed after co-precipitation or sintering of the specific component has a structure with a distinct crystalline phase or a multi-component mixed amorphous structure.

17. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 16, characterized in that, The garnet solid electrolyte is Li7La3Zr2O. 12 The LLZO precursor comprises a lithium source compound, a lanthanum source compound, and a zirconium source compound; wherein the lithium source compound is selected from at least one of lithium oxide, lithium hydroxide, and lithium carbonate; the lanthanum source compound is selected from at least one of lanthanum oxide, lanthanum hydroxide, and lanthanum carbonate; and the zirconium source compound is selected from at least one of zirconium oxide, zirconium hydroxide, and zirconium carbonate.

18. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 16, characterized in that, The LLZO precursor also contains at least one of the following doping elements: aluminum, gallium, tantalum, niobium, and copper.

19. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that, In step D, the oxygen sintering process involves first heating the lithium source to 400°C to 700°C in a pure oxygen atmosphere and maintaining this temperature for 1 to 4 hours, so that the lithium source is completely melted and fully mixed with other substances in the precursor powder. Then, the temperature is raised to 800°C to 1000°C and maintained for 6 to 12 hours. Finally, the temperature is allowed to cool naturally to room temperature in a pure oxygen atmosphere.

20. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 1, characterized in that, It also includes the following steps: Step E: After mechanically crushing the sintered powder, it is then sieved through a sieve.

21. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 20, characterized in that, After sieving, the D50 particle size of the NCM particles is 2 to 10 micrometers; the thickness of the glass phase layer is between 5 nanometers and 100 nanometers; and the maximum radial dimension of the LLZO particles is less than 80 nanometers.

22. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 20, characterized in that, It also includes the following steps: Step F: Mixing multiple carbon nanotubes, multiple nanoscale amorphous carbon and the sintered powder after sieving to form multiple positive electrode particles coated with carbon material; wherein, carbon nanotubes are abbreviated as CNT.

23. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a wet one-time sintering process as described in claim 22, characterized in that, The plurality of carbon nanotubes comprises a plurality of short-chain carbon nanotubes and a plurality of long-chain carbon nanotubes. The length of each short-chain carbon nanotube is between 0.5 micrometers and 1 micrometer, and the length of each long-chain carbon nanotube is between 3 micrometers and 8 micrometers. The short-chain carbon nanotubes are used to bridge each LLZO particle and the corresponding cathode particle. The long-chain carbon nanotubes are used to coat the cathode particle. The size of each nanoscale amorphous carbon is between 20 nanometers and 100 nanometers. Each nanoscale amorphous carbon system fills the gaps formed by the interlacing of the plurality of carbon nanotubes.

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