Method for manufacturing positive electrode particles coated with ceramic particles and glass phase continuous layer by using dry-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 dry-type one-time sintering process, which comprises the following steps of: mixing a nickel-cobalt-manganese precursor, a lithium source, a glass phase precursor and an LLZO (lithium lanthanum zirconium oxide) precursor in a mixing machine to form a precursor mixture; placing the precursor mixture in a sintering furnace for aerobic sintering to obtain sintered powder formed by a plurality of positive electrode particles; wherein the lithium source is firstly melted and decomposed into lithium oxide in the aerobic sintering process, and the lithium oxide reacts with the nickel cobalt manganese precursor and the LLZO precursor to generate a plurality of NCM (nickel cobalt lithium manganate) particles and a plurality of LLZO particles; the glass phase precursor is melted to form a layer of glass phase to coat the outer surface of each NCM particle, and the LLZO particles are distributed in the glass phase layer or on the outer surface of the glass phase layer to integrally form a plurality of positive electrode particles.

Description

Technical Field

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

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

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

[0004] Existing technologies for preparing NCM composite cathode particles coated with ceramic particles and a glass phase layer employ a two-step sintering method: first, NCM particles and ceramic particles are prepared separately using precursors; then, the NCM particles are sintered with a glass phase material to coat their surfaces with a glass phase layer; finally, the ceramic particles are mixed and stirred with the glass-coated NCM particles to form the composite cathode particles. However, this method requires two sintering steps, which is time-consuming, energy-intensive, and has high manufacturing costs. Summary of the Invention

[0005] 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 dry one-time sintering process. The dry one-time sintering process directly forms cathode particles that combine glass phase and ceramic particles, thereby improving production efficiency and reducing time costs.

[0006] The purpose of this invention is to address the problems of the prior art. This invention proposes a method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-step sintering process. The method involves coating the NCM particles with a glass phase layer, which isolates the NCM particles from direct contact with the electrolyte, reduces interfacial side reactions, and lowers the interfacial impedance for lithium ions to enter and exit the NCM particles. The LLZO particles located within the glass phase layer have the capacity to accommodate and equalize lithium ions, and can disperse the lithium ion pathway, thus providing better lithium ion conduction. This invention utilizes a one-step 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 particles are further coated with carbon nanotubes and nanoscale amorphous carbon, which increases electron conductivity on the cathode particles. The cathode with these cathode particles can serve as a ternary cathode.

[0007] 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 dry one-time sintering process. These cathode particles are used as the cathode in solid-state or near-solid-state batteries. The method includes the following steps: Step A: Multiple nickel-cobalt-manganese precursors, a lithium source, a glass phase precursor, and an LLZO precursor are placed in a mixer and mixed to form a precursor mixture. Each nickel-cobalt-manganese precursor has multiple pores on its surface. The nickel-cobalt-manganese precursor is used to form NCM (lithium nickel cobalt manganese oxide). The glass phase precursor is used to form a glass phase layer. The LLZO precursor is used to form LLZO, which is used to form the ceramic particles. Step B: The precursor mixture is placed in a sintering furnace for aerobic sintering to obtain a sintered powder formed from multiple cathode particles. The melting point of the lithium source is lower than that of the nickel-cobalt-manganese precursor and the glass phase precursor. The lithium source melts first and enters the pores of the nickel-cobalt-manganese precursor, along with the LLZO precursor. Then, at high temperature, the lithium source decomposes into highly reactive lithium oxide, which 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. Next, when the glass-phase precursor melts at high temperature, a glass phase layer is formed, coating the surface of each NCM particle. 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. The glass phase layer isolates the NCM particles from direct contact with the electrolyte, reduces interfacial side reactions, lowers the interfacial impedance for lithium ions to enter and exit the NCM particles, improves rate charge / discharge performance, and can accommodate volume changes during charge / discharge.

[0008] 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

[0009] Figure 1 This diagram shows the manufacturing steps of the positive electrode particles of the present invention.

[0010] Figure 2 This diagram shows the manufacturing process of the positive electrode particles of the present invention.

[0011] Figure 3 This diagram shows the structure of the positive electrode particles of the present invention.

[0012] Figure 4 This shows a cross-sectional view of the positive electrode particles of the present invention.

[0013] Figure 5 Examples of applications of the present invention are shown.

[0014] Figure 6 This diagram shows the structure of the positive electrode particles coated with carbon material according to the present invention.

[0015] Figure 7 This diagram shows the structure of the nickel-cobalt-manganese precursor of the present invention.

[0016] 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, an LLZO precursor 26, a precursor mixture 28, carbon nanotubes 30, short-chain carbon nanotubes 32, long-chain carbon nanotubes 34, nanoscale amorphous carbon 35, sintered powder 40, 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

[0017] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0018] Please refer to Figures 1 to 7 As shown, this case proposes a method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process. Figure 5As shown, the positive electrode particles 200 of this invention are mainly used in the positive electrode 100 of general solid-state or solid-state-like 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 difluoride), 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.

[0019] like Figure 1 and Figure 2 As shown, the method in this case includes the following steps: Step 500: The nickel-cobalt-manganese precursor 20, lithium source 22, glass phase precursor 24, and LLZO precursor 26 are placed into a mixer 150 and mixed to form a precursor mixture 28. 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). The nickel-cobalt-manganese precursor 20 is a precursor for forming NCM (lithium nickel cobalt manganese oxide); the glass phase precursor 24 is a precursor for forming a glass phase layer; and the LLZO precursor 26 is a precursor for forming LLZO, which is used to form the ceramic particles of this invention.

[0020] like Figure 7 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.

[0021] The lithium source 22 is selected from at least one of lithium hydroxide (LiOH), lithium carbonate (Li2CO3), lithium nitrate (LiNO3), or a mixture thereof.

[0022] The glass precursor 24 is an amorphous oxide, which, after heat treatment, can exhibit a lithium-ion conductivity higher than 10. -5S / cm. The amorphous oxide is an oxide of lithium with Group IIIA, IVA, or VA elements, or an amorphous oxide-based solid electrolyte. Examples of such oxides include Li₂O-RO. n Where 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 (Li7La3Zr2O). 12 It includes at least one of the following: lithium (LLZO), lithium phosphorus oxynitride (LiPON), and lithium titanium aluminum phosphate (LATP).

[0023] 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 is a structure with a distinct crystalline phase or a multi-component mixed amorphous structure.

[0024] 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 having an equivalent ratio to lanthanum (La) of no more than 0.25:3.

[0025] The mixer 150 is selected from three-dimensional mixers, parallel mixers, blade mixers, V-type mixers, and planetary mixers. A mixing medium is added during mixing in the mixer 150. This mixing medium is selected from zirconia beads, alumina beads, agate beads, and stainless steel beads. The filling rate of the mixing medium is 20% to 60%, which is the ratio of the total volume of the mixing medium to the mixing volume of the mixer 150. The particle diameter of the mixing medium is 0.5 cm to 2 cm.

[0026] Step 510: The precursor mixture 28 is placed in a sintering furnace 250 for aerobic sintering. First, the temperature is raised to 400°C to 700°C under a pure oxygen atmosphere and maintained for 1 to 4 hours, so that the lithium source 22 in the precursor mixture 28 is completely melted and fully mixed with other substances in the precursor mixture 28. 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 under a pure oxygen atmosphere to obtain sintered powder 40 formed by multiple positive electrode particles 200.

[0027] like Figure 3 and Figure 4 As shown, the lithium source 22 has a lower melting point than the nickel-cobalt-manganese precursor 20, the glass phase precursor 24, and the LLZO precursor 26. Therefore, it melts first and enters the plurality of 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 a plurality of NCM (lithium nickel cobalt manganese oxide) particles 201. At the same time, the lithium oxide also reacts with the LLZO precursor 26 to form a plurality of LLZO particles 261. On the other hand, when the glass phase precursor 24 melts at high temperature, a glass phase layer 241 is formed to coat the outer surface of each NCM particle 201, and the plurality of LLZO particles 261 are distributed inside or on the outer surface of the corresponding glass phase layer 241. The NCM particles 201 with the glass phase layer 241 and the corresponding LLZO particles 261 form the corresponding positive electrode particles 200.

[0028] 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 particles 201.

[0029] The glass phase layer 241 serves to isolate the NCM particles 201 from direct contact with the electrolyte, reducing interfacial side reactions; it also reduces the interfacial impedance for lithium ions to enter and exit the NCM particles 201, improving rate charge and discharge performance. The glass phase layer 241 can accommodate volume changes during charge and discharge, improving the mechanical properties of the powder and reducing breakage.

[0030] Step 520: The sintered powder 40 is mechanically pulverized and then sieved. Preferably, the mesh size of the sieve is 500 mesh. After sieving, the D50 particle size (mass-median-diameter, MMD) of the NCM particles 201 is 2 micrometers to 10 micrometers; the thickness of the glass phase layer 241 is between 5 nanometers and 100 nanometers; and the maximum radial dimension of the LLZO particles 261 is less than 80 nanometers.

[0031] Following step 520, steps 530A or 530B 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 530A and 530B achieve this carbon material mixing using different methods, which are explained below.

[0032] Step 530A: Sintered powder 40, multiple carbon nanotubes 30, and multiple 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 multiple carbon-coated cathode particles 300. Each carbon-coated cathode particle 300 includes a corresponding cathode particle 200, multiple corresponding carbon nanotubes 30, and multiple nanoscale amorphous carbon 35 coating the outside of the corresponding cathode particle 200 (e.g., ...). Figure 6 The mixing speed of the dry mixer is 50 rpm to 500 rpm, and the mixing time is 2 hours to 8 hours.

[0033] Step 530B: Multiple carbon nanotubes 30 and sintered powder 40 are mixed for the first time, and then multiple nano-sized amorphous carbon particles 35 are added for the second mixing to form carbon-coated cathode particles 300. Each carbon-coated cathode particle 300 comprises a corresponding cathode particle 200, multiple corresponding carbon nanotubes 30, and multiple nano-sized amorphous carbon particles 35 coating the exterior of the corresponding cathode particle 200. The first and second mixing methods are dry ball milling or wet ball milling.

[0034] 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 positive electrode particle 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%.

[0035] Short-chain carbon nanotubes 32 are used to bridge each LLZO particle 261 and the corresponding cathode particle 200, while long-chain carbon nanotubes 34 are used to coat each cathode particle 200. Nanoscale amorphous carbon 35, such as the amorphous carbon of the Super P conductive agent, is also present. The size of each nanoscale amorphous carbon 35 ranges from 20 nanometers to 100 nanometers. Each nanoscale amorphous carbon 35 fills the gaps formed by the interlacing of multiple carbon nanotubes 30. In each cathode particle 200 coated with carbon material, the total weight percentage of the corresponding multiple nanoscale amorphous carbon 35 to the weight percentage of the corresponding cathode particle 200 ranges from 0.1 wt% to 2 wt%.

[0036] Carbon nanotubes are used to increase electronic conductivity by forming conductive bridges around various LLZO particles 261, allowing electrons to conduct across each cathode particle 200. The carbon nanotubes 30 are randomly distributed on the surface of their respective cathode particles 200. Because carbon nanotubes have extremely high conductivity, electrons can conduct between different LLZO particles 261 and cathode particles 200 via these carbon nanotubes 30, thus increasing the overall conductivity of the cathode 100.

[0037] Multiple nanoscale amorphous carbon 35 and multiple carbon nanotubes 30 serve as conductive aids. 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, adding the corresponding nanoscale amorphous carbon 35 into these gaps allows the charge to be conducted between different carbon nanotubes 30 through the bridging of the nanoscale amorphous carbon 35, further increasing the current transfer efficiency.

[0038] The advantages of this invention are as follows: A glass phase layer is coated onto the outer surface of the NCM particles. This glass phase layer isolates the NCM particles from direct contact with the electrolyte, reducing interfacial side reactions and lowering the interfacial impedance for lithium ions to enter and exit the NCM particles. The LLZO particles located in the glass phase layer have the ability to accommodate and equalize lithium ions, and can disperse the lithium ion pathway, allowing for better lithium ion flow. This invention utilizes 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 particles are also coated with carbon nanotubes and nanoscale amorphous carbon, which increases the electron conduction efficiency on the cathode particles. The cathode with these cathode particles can serve as a ternary cathode.

[0039] 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 dry 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: Multiple nickel-cobalt-manganese precursors, a lithium source, a glass phase precursor, and an LLZO precursor are placed in a mixer and mixed to form a precursor mixture; each nickel-cobalt-manganese precursor has multiple pores on its surface; the nickel-cobalt-manganese precursor is used to form NCM; the glass phase precursor is used to form a glass phase layer; the LLZO precursor is used to form LLZO, which is used to form the ceramic particles; wherein LLZO is lithium lanthanum zirconium oxide, and NCM is lithium nickel cobalt manganese oxide; Step B: The precursor mixture is placed in a sintering furnace for aerobic sintering to obtain sintered powder formed by multiple cathode 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 and enter the pores of the nickel-cobalt-manganese precursor; then the lithium source decomposes into highly reactive lithium oxide at high temperature, and the lithium oxide reacts with the nickel-cobalt-manganese precursor to form multiple NCM particles; at the same time, the lithium oxide also reacts with the LLZO precursor to form multiple LLZO particles; then when the glass phase precursor melts at high temperature, a glass phase layer is formed to coat the 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 isolate the NCM particles from direct contact with the electrolyte, reduce interfacial side reactions, reduce the interfacial impedance of lithium ions entering and leaving the NCM particles, improve the rate charge and discharge performance, and can accommodate 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 dry one-time sintering process according to claim 1, characterized in that, The molar equivalent ratio of nickel-cobalt-manganese precursor, lithium source, glass phase precursor, and LLZO precursor is 1.0 : (1.02~1.25) : (0.005~0.02) : (0.005~0.02).

3. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 1, characterized in that, The size of the nickel-cobalt-manganese precursors ranges from 1 micrometer to 5 micrometers.

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

5. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to 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.

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

7. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to 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; The glass phase layer formed by this glass phase precursor is a continuous thin film layer with an amorphous crystal structure.

8. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 7, characterized in that, The amorphous oxides are oxides of lithium and elements from groups IIIA, IVA, and VA.

9. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 7, characterized in that, The amorphous oxide is Li2O-RO. n R is selected from at least one of boron, aluminum, silicon, germanium, phosphorus, and arsenic, and n = 1 to 3.

10. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 7, characterized in that, Amorphous oxides are solid electrolytes based on oxides in an amorphous state.

11. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 10, characterized in that, The amorphous oxide-based solid electrolyte is selected from at least one of amorphous perovskite-based solid electrolytes, garnet-based solid electrolytes, lithium-phosphorus-oxygen-nitrides, and lithium titanium aluminum phosphate; wherein, lithium-phosphorus-oxygen-nitrides are abbreviated as LiPON, and lithium titanium aluminum phosphate is abbreviated as LATP.

12. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 1, characterized in that, LLZO precursors refer to specific components that form cubic garnet solid electrolytes after co-firing with lithium sources. These specific components include at least one of oxides, hydroxides, and carbonates. The intermediate products formed after co-precipitation or sintering of these specific components have a structure with a distinct crystalline phase or a multi-component mixed amorphous structure.

13. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 12, characterized in that, The garnet solid electrolyte is Li7La3Zr2O. 12 The LLZO precursors include lithium source compounds, lanthanum source compounds, and zirconium source compounds; the lithium source compounds are selected from at least one of lithium oxide, lithium hydroxide, and lithium carbonate; the lanthanum source compounds are selected from at least one of lanthanum oxide, lanthanum hydroxide, and lanthanum carbonate; and the zirconium source compounds are selected from at least one of zirconium oxide, zirconium hydroxide, and zirconium carbonate.

14. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 12, characterized in that, The LLZO precursor also contains at least one doping element selected from aluminum, gallium, tantalum, niobium, and copper.

15. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 1, characterized in that, In step A, the mixer is selected from three-dimensional mixers, parallel mixers, blade mixers, V-type mixers, and planetary mixers; and when mixing in the mixer, a mixing medium is added, which is selected from zirconia beads, alumina beads, agate beads, and stainless steel beads. The filling rate of the mixing medium is 20% to 60%, which is the ratio of the total volume of the mixing medium to the mixing volume of the mixer; the particle diameter of the mixing medium is 0.5 cm to 2 cm.

16. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 1, characterized in that, In step B, the aerobic sintering system is first heated to 400°C to 700°C in a pure oxygen atmosphere and held at that temperature for 1 to 4 hours, so that the lithium source 22 in the precursor mixture 28 is completely melted and fully mixed with other substances in the precursor mixture 28. Then, the temperature is raised to 800°C to 1000°C and held at that temperature for 6 to 12 hours. Finally, it is naturally cooled to room temperature in a pure oxygen atmosphere.

17. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 1, characterized in that, It also includes: Step C: mechanically crushing the sintered powder and then sieving it through a sieve.

18. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 17, 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 each LLZO particle is less than 80 nanometers.

19. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 17, characterized in that, After step C, multiple carbon nanotubes and multiple nanoscale amorphous carbons are mixed with sieved sintered powder to form multiple carbon-coated cathode particles; the abbreviation for carbon nanotube is CNT.

20. The method for manufacturing cathode particles coated with ceramic particles and a continuous glass phase layer using a dry one-time sintering process according to claim 19, characterized in that, The plurality of carbon nanotubes includes short-chain carbon nanotubes and long-chain carbon nanotubes. The length of the short-chain carbon nanotubes is between 0.5 micrometers and 1 micrometer, and the length of the long-chain carbon nanotubes 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 nanoscale amorphous carbon has a size 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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