Method for manufacturing ncm electrode particles having an interphase layer and a nitrogen-containing carbon layer coating

Abstract

This invention discloses a method for manufacturing NCM electrode particles having a mesophase layer and a nitrogen-containing carbon layer coating, comprising the following steps: Step 500: taking a plurality of NCM composite particles and placing them with methanol into a wet mixer to form a first mixed slurry; each NCM composite particle is composed of NCM particles coated with a mesophase layer; Step 510: adding tris(hydroxymethyl)aminomethane and tris(hydroxymethyl)aminomethane hydrochloride into the wet mixer to form a second mixed slurry, such that each NCM composite particle is coated with a hydroxide ion layer; Step 520: adding dopamine hydrochloride into the wet mixer to form a third mixed slurry; thus forming a dopamine layer coating the outside of the corresponding hydroxide ion layer; Step 530: drying the third mixed slurry to obtain a mixed powder; Step 540: placing the mixed powder in a sintering furnace for calcination in an inert atmosphere; during calcination, the OH groups in the dopamine layer and the hydroxide ion layer are calcined. ‑ Ions and oxygen ions undergo a dehydration reaction, leaving only nitrogen-containing carbon molecules to form a nitrogen-containing carbon layer that coats the outside of the corresponding NCM composite particle, thus forming a corresponding NCM electrode particle.

Description

Technical Field

[0001] This invention relates to the field of electrode materials technology, and in particular to a method for manufacturing NCM electrode particles having a mesophase layer and a nitrogen-containing carbon layer coating. Background Technology

[0002] A battery is primarily formed by placing a positive electrode and a negative electrode in an electrolyte. The positive electrode consists of numerous positive electrode conductive units (positive electrode materials, such as lithium cobalt oxide) mixed and dispersed in a slurry. Generally, the positive electrode conductive units must first be mixed with the conductive slurry before being applied to the electrode sheets and assembled into a battery. Therefore, the numerous positive electrode conductive units (positive electrode materials) are connected to each other through the conductive slurry. Thus, the conductive slurry must possess conductivity or enhance conductivity to allow free electrons to migrate between different positive electrode conductive units without consuming excessive energy due to internal resistance, thereby achieving effective conductivity. Therefore, the conductivity of the slurry must be adjusted using specific conductive materials during its manufacturing process.

[0003] To increase conductivity, multiple positive electrode particles are typically filled into the positive electrode slurry. These particles can be made of materials such as NCM (lithium nickel manganese cobalt oxide), LMFP (lithium manganese iron phosphate), or mixtures thereof, and are distributed within the positive electrode slurry. However, in conventional technologies, the interfaces of the positive electrode particles are prone to side reactions, leading to a decrease in the lifespan of the positive electrode and low electronic conductivity, resulting in poor overall battery performance. Summary of the Invention

[0004] The purpose of this invention is to propose a novel method for manufacturing NCM electrode particles with a mesophase layer and a nitrogen-containing carbon layer. The method involves coating the positive electrode particle with a mesophase layer to protect it and prevent it from degrading during sintering. Additionally, a carbon layer is coated on the outside of the mesophase layer to increase conductivity.

[0005] Therefore, the purpose of this invention is to solve the aforementioned problems in the prior art. This invention proposes a method for manufacturing NCM electrode particles with a mesophase layer and a nitrogen-containing carbon layer coating. The mesophase layer coating the outer surface of the NCM particles reduces the risk of NCM particle degradation due to the use of inert gases in the manufacturing process, and the mesophase layer increases ion conduction efficiency. Furthermore, coating the mesophase layer with a nitrogen-containing carbon layer further increases the conductivity of the entire composite NCM particle.

[0006] To achieve the above objectives, this invention proposes a method for manufacturing NCM electrode particles coated with a mesophase layer and a nitrogen-containing carbon layer. These are NCM electrode particles primarily used as electrodes in solid-state or near-solid-state batteries. The method includes the following steps: Step 500: Multiple NCM composite particles are placed in a wet mixer and mixed with methanol at a first rotation speed to form a first slurry. Each NCM composite particle is composed of NCM particles coated with a mesophase layer. This mesophase layer consists of a glass phase layer and multiple ceramic particles distributed therein. The mesophase layer protects the corresponding NCM particles and also increases the lithium-ion conduction efficiency. The glass phase layer prevents direct contact between the NCM particles and the electrolyte within the electrode, reducing interfacial side reactions and simultaneously reducing the interfacial impedance for lithium ions to enter and exit the NCM particles. Step 510: Tris(hydroxymethyl)aminomethane... Alkane and tris(hydroxymethyl)aminomethane hydrochloride are added to the wet mixer and stirred with the first mixed slurry to form a second mixed slurry. After stirring in step 510, the outer surface of each NCM composite particle is coated with a hydroxide ion layer. In step 510, after adding tris(hydroxymethyl)aminomethane and tris(hydroxymethyl)aminomethane hydrochloride, the speed of the wet mixer is increased to a second speed, which is greater than the first speed in step 500. The purpose of adding tris(hydroxymethyl)aminomethane hydrochloride is to control the pH value of the chemical reaction, because the reaction between the NCM composite particles and tris(hydroxymethyl)aminomethane requires catalysis under alkaline conditions. Step 520: Dopamine hydrochloride is added to the wet mixer and stirred with the second mixed slurry to form a third mixed slurry. The dopamine molecules in the dopamine hydrochloride have OH groups... - The ions will react with the third OH group of the hydroxide ion layer on each of the NCM composite particles. - The ions undergo a dehydration polymerization reaction, causing each NCM composite particle to combine with a corresponding plurality of dopamine molecules. These corresponding plurality of dopamine molecules then undergo a copolymerization reaction, forming a dopamine layer that coats the outer side of the hydroxide ion layer on the corresponding NCM composite particle. Step 530: The third mixed slurry is dried to obtain a mixed powder. Step 540: The mixed powder is placed in a sintering furnace and calcined in an inert atmosphere. During calcination, the OH groups within the dopamine layer and the hydroxide ion layer... -In an inert atmosphere, oxygen ions undergo a dehydration reaction, leaving only nitrogen-containing carbon molecules. These nitrogen-containing carbon molecules combine with oxygen ions containing lone pairs of electrons on the surface of the mesophase layer using van der Waals forces, forming a nitrogen-containing carbon layer that coats the outside of the corresponding NCM composite particle. The NCM particle with the nitrogen-containing carbon layer and the mesophase layer forms a corresponding NCM electrode particle. The nitrogen-containing carbon layer is used to increase the conductivity of the entire NCM electrode particle. The nitrogen-containing carbon layer is composed of multiple ordered carbon structures containing carbon and nitrogen double bonds (C=N). 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

[0007] Figure 1 This diagram shows the manufacturing steps of the NCM electrode particles in this case. Figure 2 This diagram shows the manufacturing process of the NCM electrode particles in this case. Figure 3 This diagram shows an enlarged view of the structure of the NCM composite particles in this case. Figure 4 This shows a cross-sectional view of the NCM composite particles in this case. Figure 5 This diagram shows the structure of the NCM composite particles in this case, which are coated with a hydroxide ion layer. Figure 6 This diagram shows the structure of the dopamine layer covering the outer surface of the hydroxide ion layer in this case. Figure 7 This diagram shows the structure of the NCM electrode particles in this case. Figure 8 This shows a cross-sectional view of the NCM electrode particles in this case. Figure 9 This example demonstrates the application of this case. Figure 10 This diagram shows the structure of the secondary NCM composite particles in this case. Detailed Implementation Please refer to Figures 1 to 10 The diagram illustrates the method of this invention for manufacturing NCM electrode particles having a mesophase layer and a nitrogen-containing carbon layer coating.

[0008] like Figure 9As shown, the NCM electrode particles 100 coated with a mesophase layer and a carbon layer in this invention are mainly used for the electrode 10 of a solid-state or near-solid-state battery. In application, multiple NCM electrode particles 100 can be disposed within the electrode 10, which is particularly the positive electrode of the solid-state or near-solid-state battery. The particle size of each NCM electrode particle 100 is less than 10 micrometers. The electrode 10 includes an electrode substrate 11 for supporting the material of the electrode 10; an electrode slurry layer 17 is coated on the electrode substrate 11, and the electrode slurry layer 17 includes an electrode slurry 12 as a binder. The electrode slurry layer 17 also includes multiple NCM electrode particles 100. The weight percentage of the multiple NCM electrode particles 100 in the electrode slurry layer 17 is between 80 wt% and 98 wt%.

[0009] The method for manufacturing the NCM electrode particle 100 in this case is as follows: Figure 1 As shown, it includes the following steps: Step 500: Take multiple NCM (lithium nickel manganese cobalt oxide) composite particles 110 and methanol 111 and place them into a wet mixer 500 to mix and form a first mixed slurry 120. Each NCM composite particle 110 is composed of NCM particles 15 coated with a mesophase layer 16 (e.g., ...). Figure 3 NCM is a ternary oxide. The size (D50) of each NCM particle 15 is between 3 and 5 micrometers (its D90 does not exceed 10 micrometers), and it has a single crystal structure. Each NCM particle 15 has an irregular polyhedral shape. The radial thickness of the mesophase layer 16 is between 50 nanometers and 1 micrometer. The weight ratio of the NCM composite particles 110 to the methanol 111 is between 1:3 and 1:10.

[0010] like Figure 4 As shown, the mesophase layer 16 is composed of a glass phase layer 241 and a plurality of ceramic particles 242 distributed therein. The mesophase layer 16 protects the corresponding NCM particles 15 inside and also increases the lithium-ion conduction efficiency. The particle size of each ceramic particle 242 is less than 100 nanometers. The radial thickness of the glass phase layer 241 is between 50 nanometers and 1 micrometer. In each mesophase layer 16, the weight ratio of the total weight of the plurality of ceramic particles 242 to the total weight of the glass phase layer 241 is 10~1:1~10.

[0011] The material forming the glass phase layer 241 is an amorphous oxide, which, after heat treatment, has a lithium-ion conductivity higher than 10. -5S / cm of amorphous oxide. This amorphous oxide is (i) an oxide of lithium with elements of group IIIA, IVA, or VA, or (ii) an amorphous oxide-based solid electrolyte. Examples of such oxides include Li₂O-RO. x Where x = 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 The glass phase layer 241 is selected from at least one of lithium phosphorus oxynitride (LiPON) and lithium aluminum titanium phosphate (LATP). The glass phase layer 241 does not have a specific crystal structure and is a continuous thin film layer coating the outer surface of the NCM particles 15.

[0012] The ceramic particles 242 are either protective oxides or oxide ceramics that enhance lithium-ion conductivity. The protective oxides include at least one of alumina and silicon oxide; the oxide ceramics that enhance lithium-ion conductivity include solid electrolyte materials.

[0013] This solid electrolyte material has lithium-ion conductivity (ionic conductivity greater than 10). -5 Oxides or phosphates with a diffusion coefficient of (cm² / s) or those having a garnet or perovskite structure. Examples of lithium-ion conductive oxides or phosphates include lithium aluminum titanium phosphate (LATP) and lithium aluminum germanium phosphate (LAGP) with a NASICON (sodium (Na) super ionic conductor) structure, or lithium phosphates with lithium conductivity such as lithium phosphate (Li₃PO₄). Examples of oxides with a garnet or perovskite structure include lithium lanthanum zirconium oxide (Li₇La₃Zr₂O₄). 12 The ceramic particles 242 can also be any combination of the above components in any proportion.

[0014] The glass phase layer 241 can block the direct contact between the NCM particles 15 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 15, 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.

[0015] The wet mixer 500 contains multiple zirconium beads, which are mixed at a first rotational speed of 2200 rpm ± 20%. The zirconium beads have a particle size of 0.7 mm to 0.9 mm. The total volume filling rate of the zirconium beads is 70% to 90%, which is the ratio of the total volume of the zirconium beads to the mixing volume of the wet mixer 500. The mixing time is 1 hour to 1.5 hours, and the operating temperature is 20℃ ± 4℃.

[0016] Step 510: Tris(hydroxymethyl)aminomethane ((HOCH2)3CNH2) 13 and tris(hydroxymethyl)aminomethane hydrochloride (NH2C(CH2OH)3·HCl) 14 are added to the wet mixer 500 and stirred with the first mixed slurry 120 to form a second mixed slurry 130. After stirring in step 510, the outer surface of each NCM composite particle 110 is coated with a hydroxide ion (OH-). - ) Layer 24. (e.g.) Figure 5 As shown, the surface of the mesophase layer 16 of the NCM composite particle 110 has oxygen ions containing lone pairs of electrons, and the OH- ions in the hydroxide ion layer 24... - The ion contains the OH groups of the tris(hydroxymethyl)aminomethane molecule in the tris(hydroxymethyl)aminomethane 13 and the tris(hydroxymethyl)aminomethane hydrochloride 14. - The OH group of the tris(hydroxymethyl)aminomethane molecule - The ion contains the first OH group. - Ions, second OH- - ions and the third OH group - Ions, wherein the first OH group - Ions, second OH- - The ions form bonds with the oxygen ions containing lone pairs of electrons in the mesophase layer 16 through hydrogen bonding, while the third OH group... - The ions will extend toward the outer surface of the corresponding NCM composite particle 110. Only two tris(hydroxymethyl)aminomethane molecules are shown in the figure for illustrative purposes and are not intended to limit the scope of this invention.

[0017] The weight ratio of the tris(hydroxymethyl)aminomethane 13 to the tris(hydroxymethyl)aminomethane hydrochloride 14 is 8:2. The thickness of the hydroxide ion layer 24 is between 0.5 nanometers and 2 nanometers.

[0018] In step 510, after adding the tris(hydroxymethyl)aminomethane 13 and the tris(hydroxymethyl)aminomethane hydrochloride 14, the speed of the wet mixer 500 is increased to a second speed for stirring, that is, the second speed is greater than the first speed in step 500; the second speed is 2400 rpm ± 20%, the stirring time is 0.5 hours, and the operating temperature is 20℃ ± 4℃.

[0019] The purpose of adding tris(hydroxymethyl)aminomethane hydrochloride 14 is to control the pH value of the chemical reaction. The reaction between the NCM composite particles 110 and tris(hydroxymethyl)aminomethane 13 requires alkaline catalysis, but excessive alkalinity can cause the NCM composite particles 110 to hydrolyze and deteriorate. Therefore, adding tris(hydroxymethyl)aminomethane hydrochloride 14 lowers the overall pH value, reducing the alkalinity of the reaction.

[0020] Step 520: Add dopamine hydrochloride 25 to the wet mixer 500 and stir with the second mixed slurry 130 to form a third mixed slurry 140. The dopamine molecules in the dopamine hydrochloride 25 have OH groups... - The ions will react with the OH groups of the hydroxide ion layer 24 on each of the NCM composite particles 110. - Ions generate dehydration-triggered polymerization, such as... Figure 6 This allows each NCM composite particle 110 to bind with a corresponding plurality of dopamine molecules, wherein these corresponding plurality of dopamine molecules undergo a copolymerization reaction to form a dopamine layer 35 that coats the outer side of the hydroxide ion layer 24 on the corresponding NCM composite particle 110. The thickness of the dopamine layer 35 is between 10 nanometers and 200 nanometers.

[0021] The weight ratio of the total weight of the NCM composite particles 110, the total weight of the tris(hydroxymethyl)aminomethane 13 and the tris(hydroxymethyl)aminomethane hydrochloride 14, and the weight of the dopamine hydrochloride 25 is 100~1000:0.8~1:2.2~2.4.

[0022] Step 530: The third mixed slurry 140 is dried to obtain a mixed powder 150. The drying method is selected from rapid liquid removal methods such as vacuum baking, reduced pressure concentration, and spray drying, so that the liquid (such as methanol 111) in the third mixed slurry 140 is evaporated.

[0023] Step 540: The mixture powder 150 is placed in a sintering furnace 460 and calcined in an inert atmosphere. During calcination, the OH groups in the dopamine layer 35 and the hydroxide ion layer 24... - Ions and oxygen undergo a dehydration reaction in an anaerobic environment (i.e., an inert atmosphere), leaving only multiple ordered carbon atoms with carbon-nitrogen double bonds (C=N) (such as...). Figure 7 These ordered carbon structures containing carbon and nitrogen double bonds (C=N) are bonded to oxygen ions with lone pairs of electrons on the surface of the mesophase layer 16 by van der Waals forces, forming a nitrogen-containing carbon layer 36 that coats the outer side of the corresponding NCM composite particle 110. Figure 8 As shown, the NCM particle 15 having the nitrogen-containing carbon layer 36 and the mesophase layer 16 forms a corresponding NCM electrode particle 100. The radial thickness of the nitrogen-containing carbon layer 36 is ≤0.2 micrometers. The nitrogen-containing carbon layer 36 can increase the conductivity of the entire NCM electrode particle 100.

[0024] The purpose of using a nitrogen-containing carbon layer is that nitrogen-doped carbon molecules facilitate electronic conductivity, lithium-ion conduction, and alter the potential of the NCM particle 15, thereby improving the overall battery performance. In this manufacturing process, a nitrogen-containing polymer material (i.e., the dopamine hydrochloride 25) is coated onto the outer side of the hydroxide ion layer 24 of the corresponding NCM composite particle 110, followed by calcination in an inert atmosphere. Since carbon and nitrogen can form conjugated bonds, the presence of these bonds alters the band structure, lowering the energy required for electron transitions to the conduction band, thus improving overall electronic conductivity. The dopamine hydrochloride 25 added in step 520 can also be other nitrogen-containing polymer materials, such as polydopamine. After calcination in step 540, the size (D50) of the NCM particles 15 is 3 to 5 micrometers; the radial thickness of the mesophase layer 16 is between 50 nanometers and 1 micrometer; the size of the ceramic particles 242 is less than 100 nanometers; and the radial thickness of the nitrogen-containing carbon layer 36 is ≤0.2 micrometers.

[0025] Step 550: The multiple NCM electrode particles 100 are mechanically crushed and then sieved through a screen, preferably with a mesh size of 500.

[0026] This invention may also include step 560: This invention may further increase the conductivity by coating the outer surface of the NCM electrode particle 100 with a carbon material, the carbon material comprising multiple carbon nanotubes 40 (CNTs) and multiple nanoscale amorphous carbon 45 coated on the outer surface of the NCM electrode particle 100, thereby forming a primary and secondary NCM composite particle 50.

[0027] like Figure 10As shown, the carbon nanotubes 40 have a size between 200 nm and 500 nm, and the nanoscale amorphous carbon 45 has a size between 10 nm and 40 nm. The nanoscale amorphous carbon 45 is, for example, the amorphous carbon of the Super P conductive agent. In the secondary NCM composite particles 50, the weight ratio of the total weight of the plurality of carbon nanotubes 40 and the nanoscale amorphous carbon 45 to the total weight of the NCM particles 15 is 0.2~2:99.8~98.

[0028] Carbon nanotubes are used to increase electronic conductivity, allowing electrons to conduct across each NCM electrode particle 100. Each carbon nanotube 40 is randomly distributed on the surface of its corresponding NCM electrode particle 100. Because carbon nanotubes have extremely high conductivity, electrons can conduct between different NCM electrode particles 100 via the carbon nanotubes 40, thus increasing the overall conductivity of the positive electrode.

[0029] The multiple nanoscale amorphous carbon 45 and the multiple carbon nanotubes 40 both serve as conductive aids. Because each nanoscale amorphous carbon 45 is in the form of particles, while each carbon nanotube 40 is in the form of elongated strips, gaps will be formed between the multiple carbon nanotubes 40 crisscrossing on the NCM electrode particle 100. These gaps cannot conduct current. Therefore, by adding the corresponding nanoscale amorphous carbon 45 into these gaps, the charge can be conducted between different carbon nanotubes 40 through the bridging of the nanoscale amorphous carbon 45, further increasing the current transfer efficiency.

[0030] The advantage of this design is that coating the NCM particles with a mesophase layer reduces the risk of NCM particle degradation due to the use of inert gases in the manufacturing process, and the mesophase layer also increases ion conduction efficiency. Furthermore, coating the mesophase layer with a nitrogen-containing carbon layer further enhances the conductivity of the entire composite NCM particle.

[0031] In conclusion, the thoughtful and user-friendly design in this case is highly in line with actual needs. Its specific improvements over existing deficiencies represent a significant breakthrough compared to prior art, offering genuine functional enhancements that are not easily achieved. Furthermore, since this case has not been publicly disclosed or revealed in domestic or international literature or markets, it complies with patent law requirements.

[0032] 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 NCM electrode particles having a mesophase layer and a nitrogen-containing carbon layer coating, characterized in that, It is an NCM electrode particle, mainly used as an electrode in solid-state or solid-state-like batteries; it includes the following steps: Step 500: Take multiple NCM composite particles and methanol and put them into a wet mixer and mix them at a first speed to form a first mixed slurry; each NCM composite particle is composed of NCM particles coated with a mesophase layer; The mesophase layer consists of a glass phase layer and multiple ceramic particles distributed therein; the mesophase layer is used to protect the corresponding NCM particles inside and can also increase the effectiveness of lithium ion conduction. The glass phase layer can prevent the NCM particles from directly contacting the electrolyte in the electrode, reducing interfacial side reactions; at the same time, it reduces the interfacial resistance of lithium ions entering and leaving the NCM particles. Step 510: Tris(hydroxymethyl)aminomethane and tris(hydroxymethyl)aminomethane hydrochloride are added to the wet mixer and stirred with the first mixed slurry to form a second mixed slurry. After stirring in step 510, each NCM composite particle is coated with a hydroxide ion layer on its outer surface. In step 510, after adding the tris(hydroxymethyl)aminomethane and the tris(hydroxymethyl)aminomethane hydrochloride, the speed of the wet mixer is increased to a second speed for stirring, that is, the second speed is greater than the first speed in step 500. The purpose of adding the tris(hydroxymethyl)aminomethane hydrochloride is to control the pH value of the chemical reaction, because the reaction between the NCM composite particles and the tris(hydroxymethyl)aminomethane needs to be catalyzed under alkaline conditions. Step 520: Add dopamine hydrochloride to the wet mixer and stir with the second mixed slurry to form a third mixed slurry; wherein the OH groups of dopamine molecules in the dopamine hydrochloride... - The ions will react with the OH groups in the hydroxide ion layer on each of the NCM composite particles. - The ions undergo a dehydration polymerization reaction, causing each NCM composite particle to combine with multiple corresponding dopamine molecules. These multiple corresponding dopamine molecules will undergo a copolymerization reaction to form a dopamine layer that coats the outside of the hydroxide ion layer on the corresponding NCM composite particle. Step 530: Dry the third mixed slurry to obtain a mixed powder; Step 540: The mixture powder is placed in a sintering furnace and calcined under an inert atmosphere; during calcination, the OH groups in the dopamine layer and the hydroxide ion layer... - In an inert atmosphere, ions and oxygen ions undergo a dehydration reaction, leaving only nitrogen-containing carbon molecules. These nitrogen-containing carbon molecules combine with oxygen ions containing lone pairs of electrons on the surface of the mesophase layer using van der Waals forces to form a nitrogen-containing carbon layer that coats the outside of the corresponding NCM composite particle. The NCM particle with the nitrogen-containing carbon layer and the mesophase layer forms a corresponding NCM electrode particle. The nitrogen-containing carbon layer is used to increase the conductivity of the entire NCM electrode particle.

2. The method as described in claim 1, characterized in that, The nitrogen-containing carbon layer system is composed of multiple ordered carbon structures containing carbon and nitrogen double bonds.

3. The method as described in claim 1, characterized in that, The glass phase layer is an amorphous oxide, which has a lithium-ion conductivity higher than 10 after heat treatment. -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 NCM particles.

4. The method as described in claim 3, characterized in that, The non-crystalline oxide is an amorphous oxide-based solid electrolyte.

5. The method as described in claim 3, characterized in that, The amorphous oxide is selected from at least one of amorphous perovskite solid electrolytes, garnet solid electrolytes, lithium-phosphorus-oxygen-nitrides, and lithium titanium aluminum phosphate.

6. The method as described in claim 1, characterized in that, The ceramic particles are either protective oxides or oxide ceramics that can improve lithium-ion conductivity.

7. The method as described in claim 1, characterized in that, The protective oxide is selected from at least one of alumina, silicon oxide, etc., and the oxide ceramic that enhances lithium-ion conductivity is a solid electrolyte material. The solid electrolyte material is an oxide or phosphate with lithium-ion conductivity, wherein lithium-ion conductivity refers to an ionic conductivity greater than 10. -5 cm² / s, or an oxide with a garnet or perovskite structure, wherein the oxide or phosphate with lithium-ion conductivity is selected from at least one of lithium aluminum titanium phosphate and lithium aluminum germanium phosphate with a NASICON structure, wherein the oxide with a garnet or perovskite structure is selected from at least one of lithium lanthanum zirconium oxide or lithium lanthanum titanium oxide.

8. The method as described in claim 1, characterized in that, Using the median diameter D50 as an indicator, the particle size of the NCM electrode particles is less than 10 micrometers; the size of the NCM particles is between 3 and 5 micrometers, and they are single-crystal structures; the radial thickness of the mesophase layer is between 50 nanometers and 1 micrometer; the weight ratio of the NCM composite particles to the methanol is 1:3 to 1:10; the particle size of each ceramic particle is less than 100 nanometers; the radial thickness of the glass phase layer is between 50 nanometers and 1 micrometer; and in each mesophase layer, the weight ratio of the total weight of the multiple ceramic particles to the total weight of the glass phase layer is 10 to 1:1 to 10.

9. The method as described in claim 1, characterized in that, The wet mixer contains multiple zirconium beads with a particle size of 0.7 mm to 0.9 mm. The total volume of the zirconium beads is filled to a ratio of 70% to 90%, which is the ratio of the total volume of the zirconium beads to the mixing volume of the wet mixer. In step 500, the first rotation speed is 2200 rpm ± 20%, the mixing time is 1 hour to 1.5 hours, and the operating temperature is 20℃ ± 4℃.

10. The method as described in claim 1, characterized in that, In step 510, the OH group of the hydroxide ion layer... - The ion contains the OH group of the tris(hydroxymethyl)aminomethane and the tris(hydroxymethyl)aminomethane hydrochloride molecule. - The OH group of the tris(hydroxymethyl)aminomethane molecule - The ion contains the first OH group. - Ions, second OH- - ions and the third OH group - Ions, wherein the first OH group - Ions, second OH- - The ions form bonds with the oxygen ions containing lone pairs of electrons in the mesophase layer through hydrogen bonding, and the third OH group... - The ions will extend toward the outer surface of the corresponding NCM composite particle.

11. The method as described in claim 1, characterized in that, The weight ratio of the trihydroxymethylaminomethane to the trihydroxymethylaminomethane hydrochloride is 8:2; the weight ratio of the total weight of the NCM composite particles, the total weight of the trihydroxymethylaminomethane and the trihydroxymethylaminomethane hydrochloride, and the weight of the dopamine hydrochloride is 100~1000:0.8~1:2.2~2.

4.

12. The method as described in claim 1, characterized in that, The thickness of the dopamine layer ranges from 10 nanometers to 200 nanometers.

13. The method as described in claim 1, characterized in that, The second rotation speed is 2400 rpm ± 20%, the stirring time is 0.5 hours, and the operating temperature is 20℃ ± 4℃.

14. The method as described in claim 1, characterized in that, The drying method in step 530 is selected from methods that quickly remove liquid, such as vacuum baking, reduced pressure concentration, and spray drying.

15. The method as described in claim 1, characterized in that, After calcination in step 540, the NCM particle size is 3 to 5 micrometers, with median diameter D50 as the indicator; the radial thickness of the mesophase layer is between 50 nanometers and 1 micrometer; the ceramic particle size is less than 100 nanometers; and the radial thickness of the nitrogen-containing carbon layer is ≤0.2 micrometers.

16. The method as described in claim 1, characterized in that, It also includes: Step 550: Mechanically crush the multiple NCM electrode particles and then sieve them through a screen, preferably with a screen mesh size of 500 mesh.

17. The method as described in claim 1, characterized in that, It also includes: Step 560: Coating the outer surface of the NCM electrode particle with carbon material to further increase conductivity. The carbon material contains multiple carbon nanotubes and multiple nanoscale amorphous carbons coated on the outer surface of the NCM electrode particle to form primary and secondary NCM composite particles.

18. The method as described in claim 17, characterized in that, The size of the carbon nanotubes ranges from 200 nanometers to 500 nanometers, and the size of the nanoscale amorphous carbon ranges from 10 nanometers to 40 nanometers. In a single secondary NCM composite particle, the weight ratio of the total weight of the multiple carbon nanotubes and the nanoscale amorphous carbon to the total weight of the NCM particle is 0.2~2:99.8~98.

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