Method for producing NCM positive electrode particles coated with LLZO and glass phase in a high-speed rotation process

Abstract

To provide a method for producing NCM positive electrode particles coated with LLZO and a glass phase by a high-speed rotation process.SOLUTION: A step A of adding a plurality of NCM (lithium nickel manganese cobalt oxide) large particles and a glass phase material into a first stirrer and stirring and mixing them sufficiently by high-speed rotation to form NCM particles having a plurality of glass phases, wherein a glass phase formed of the glass phase material is attached to the whole or part of the surface of each of the NCM large particles, and the glass phase material is an amorphous solid electrolyte or a non-oxide solid electrolyte having a lithium ion conductivity of more than 10-5S / cm; and a step B of adding a plurality of LLZO fine particles and a plurality of NCM particles having the glass phase into a second stirrer and stirring and mixing them sufficiently by high-speed rotation to form a plurality of composite NCM particles, wherein each of the LLZO fine particles is distributed in or on the glass phase of each of the NCM particles having the glass phase.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to positive electrode particles, and more particularly to a method for producing NCM positive electrode particles coated with LLZO and glass phases using a high speed rotary process. [Background technology]

[0002] In prior art batteries, a plurality of positive electrode particles are packed into the battery's positive electrode slurry to enhance electrical conductivity, and the positive electrode particles are made of a material selected from lithium nickel manganese cobalt oxide (NCM), lithium manganese iron phosphate (LMFP), or a mixture thereof, and the positive electrode particles are distributed within the positive electrode slurry. Summary of the Invention [Problem to be solved by the invention]

[0003] However, in the above-mentioned conventional technology, side reactions tend to occur at the interface of the positive electrode particles, shortening the service life of the positive electrode and reducing the overall performance of the battery due to low electron conductivity.

[0004] Furthermore, to ensure complete coverage of the cathode particle surface, it is necessary to coat the surface of the cathode particle with a glass phase. A common glass phase formation method involves high-temperature smelting and quenching, and adjusting the heat treatment conditions to prevent the crystal lattice of the material from arranging in an orderly fashion at room temperature. However, a drawback of this method is that it can only be used with glass phase oxide materials that can withstand prolonged heating (e.g., garnets, perovskites, or phosphates). Conversely, for glass phase non-oxide materials with low heat resistance (e.g., halide and sulfide systems), prolonged heating and temperature retention can result in a decrease in their lithium ion conductivity.

[0005] The present invention has been made in view of the above-mentioned conventional problems, and a main object of the present invention is to provide a method for producing NCM positive electrode particles coated with LLZO and a glass phase using a high-speed rotation process. [Means for solving the problem]

[0006] To address the above-mentioned problems, one embodiment of the present invention provides a method for producing NCM positive electrode particles coated with LLZO and a glass phase using a high-speed rotation process. The outer surfaces of the NCM large particles are coated with a glass phase. The glass phase prevents the NCM large particles from directly contacting the electrolyte and suppresses interfacial side reactions. At the same time, it reduces the interfacial resistance when lithium ions enter and exit the NCM large particles, improves charge / discharge performance, accommodates volume changes during charge / discharge, improves the mechanical properties of the powder, and reduces fracture. The present invention coats the NCM large particles with a plurality of LLZO fine particles, which have the ability to accommodate and uniformly guide lithium ions. As lithium ions pass through the positive electrode, the LLZO fine particles guide the lithium ions, dispersing their paths. This provides more suitable paths for the lithium ions. The present invention further coats the outer surface of the NCM large particles that cover the LLZO fine particles with multiple carbon nanotubes and nanoscale amorphous carbon, enabling electron conduction through the composite NCM particles, and filling the spaces between the multiple carbon nanotubes with the nanoscale amorphous carbon to form a more complete electron conduction path. In this way, the present invention provides stability to the entire cathode structure and also reduces the amount of cobalt used.

[0007] At least the following points will become clear from the description and drawings to be described later. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a flowchart illustrating a method for manufacturing positive electrode particles according to an embodiment of the present invention. [Figure 2] 1 is a diagram showing a configuration of a positive electrode particle according to an embodiment of the present invention. [Figure 3] FIG. 1 is a structural diagram showing a positive electrode according to an embodiment of the present invention. [Figure 4] 1 is a structural diagram showing a composite NCM particle according to one embodiment of the present invention. [Figure 5] 1 is a structural diagram showing a composite NCM particle and short-chain carbon nanotubes according to an embodiment of the present invention. [Figure 6] 1 is a diagram showing a configuration of a positive electrode particle coated with a carbon material according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0010] First, a specific embodiment of a method for producing NCM positive electrode particles coated with LLZO and a glass phase according to the present invention by a high-speed rotation process will be described with reference to FIGS. 1 to 6. FIG.

[0011] The NCM positive electrode particles of the present invention are primarily used in a positive electrode 100 of a typical solid-state or solid-state battery. The positive electrode 100 includes a positive electrode substrate 10 and a positive electrode slurry layer 12 applied to the positive electrode substrate 10. The positive electrode slurry layer 12 includes a positive electrode slurry 14 having a binder, and a plurality of positive electrode particles 200 distributed within the positive electrode slurry 14 (see FIG. 3). The binder may be PVDF (polyvinylidene difluoride), PEO (polyethylene oxide), or the like. The plurality of positive electrode particles 200 occupy 80 wt% to 98 wt% of the positive electrode slurry layer 12.

[0012] The NCM positive electrode particles coated with LLZO and glass phases according to the present invention are the positive electrode particles 200, and the manufacturing method thereof (see FIG. 1) includes the following steps, each of which will be described below.

[0013] <Process 500> An NCM (lithium nickel manganese cobalt oxide) material is prepared, and the NCM material is composed of a plurality of NCM large particles 22. NCM is a ternary oxide. The size of each of the NCM large particles 22 ranges from 3 μm to 5 μm and has a single crystal structure. Each of the NCM large particles 22 has an irregular cubic shape. The plurality of NCM large particles 22 and a glass phase material are simultaneously placed into a first agitator and thoroughly agitated at high speed to uniformly mix the plurality of NCM large particles 22 and the glass phase material, forming a plurality of NCM particles 250 having a glass phase. Each of the NCM particles 250 having a glass phase contains a corresponding NCM large particle 22, and the exterior of each NCM large particle 22 is covered with a glass phase 25 formed of the glass phase material. The first agitator is a dry agitator (e.g., a 3D agitator or a flat roller agitator) or a wet agitator (e.g., a DC blade agitator), and anhydrous alcohol or isopropanol solvent is added to the wet agitator. The rotation speed of the first agitator ranges from 50 rpm to 3000 rpm, and the agitation time ranges from 10 minutes to 12 hours. During the mixing process in the first agitator, oxygen or dry air is added to provide atmosphere protection, protecting the NCM large particles 22 during high-speed rotation and preventing them from decomposing at high temperatures. The oxygen or dry air is added at a rate of 0.5 to 5 L / min. Due to the high-speed rotation of the first agitator, the glass phase material adheres to the entire or partial surface of each of the NCM large particles 22, and the exterior of each of the NCM large particles 22 is covered with the glass phase 25 formed by the glass phase material. The thickness of the glass phase 25 ranges from 5 nm to 100 nm.

[0014] The glass phase material has a lithium ion conductivity of 10-5 The glassy phase material is composed of an amorphous oxide or non-oxide solid electrolyte having a conductivity of greater than 1000 S / cm. The glassy phase material is an oxide of lithium and group IIIA, IVA, or VA elements (e.g., LiO-RO). x Here, R is at least one element of boron (B), aluminum (Al), silicon (Si), germanium (Ge), phosphorus (P), or arsenic (As), and x = 1 to 3; lithium halides or lithium halogen-oxides (e.g., Li-MO, where M is at least one element of the halogens fluorine (F), chlorine (Cl), bromine (Br), or iodine (I)); lithium sulfides (e.g., Li2S-P2S5); amorphous oxide-based solid electrolytes (e.g., amorphous perovskite-based solid electrolytes (Li-La-Ti-O, LLTO), garnet-based solid electrolytes (Li-La-Zr-O, LLZO), or lithium phosphorus oxynitride (LiPON)) are included.

[0015] The glass phase 25 can prevent direct contact between the NCM large particles 22 and the electrolyte, suppressing side reactions at the interface, and simultaneously reducing the interface resistance when lithium ions enter and exit the NCM large particles 22, improving the charge-discharge performance. The glass phase 25 can accommodate the volume that changes during charge and discharge, improving the mechanical properties of the powder and reducing fracture.

[0016] <Process 510> The LLZO material and a plurality of NCM particles 250 having the glass phase are mixed at high speed to form a plurality of composite NCM particles 20. The LLZO material is composed of a plurality of LLZO particles 24, each of which is made of lithium lanthanum zirconium oxide (Li7La3Zr2O 12 , LLZO), or lithium lanthanum zirconium oxide doped with at least one metal element (e.g., Li 6.2 Ga 0.8 La3Zr2O 12(This may be a gallium (Ga)-doped lithium lanthanum zirconium oxygen compound, or an aluminum (Al)-doped or barium (Ba)-doped lithium lanthanum zirconium oxygen compound.) The size of each of the NCM large particles 22 is larger than the size of each of the LLZO microparticles 24. The maximum radial size of the LLZO microparticles 24 is less than 40 nm.

[0017] The glass-phase NCM particles 250 and the LLZO microparticles 24 are simultaneously introduced into a second agitator (e.g., a 3D agitator or a flat roller agitator) and thoroughly mixed at high speed. The rotation speed of the second agitator is between 50 rpm and 3000 rpm, and the mixing time is between 10 minutes and 12 hours. Oxygen or dry air is added during the mixing process in the second agitator to provide atmosphere protection, protecting the NCM large particles 22 during high-speed rotation and preventing decomposition of the NCM large particles 22 due to high temperatures. The oxygen or dry air is added at a rate of 0.5 to 5 L / min. The high-speed rotation of the second agitator distributes each of the LLZO microparticles 24 within or on the surface of the glass phase 25 of the corresponding glass-phase NCM particle 250, thereby forming a corresponding composite NCM particle 20 from the glass-phase NCM particle 250 and the corresponding LLZO microparticle 24 (see FIG. 4).

[0018] Preferably, each of the LLZO particles 24 is composed of at least one element selected from Ga-LLZO (Ga-doped LLZO, gallium-doped lithium lanthanum zirconium oxide), Cu-LLZO (Cu-doped LLZO, copper-doped lithium lanthanum zirconium oxide), Ta-LLZO (Ta-doped LLZO, tantalum-doped lithium lanthanum zirconium oxide), Sr-LLZO (Sr-doped LLZO, strontium-doped lithium lanthanum zirconium oxide), and Al-LLZO (Al-doped LLZO, aluminum-doped lithium lanthanum zirconium oxide).

[0019] Preferably, each of the LLZO particles 24 is Cu a ,X b -LLZO, and a ,X b LLZO is a lithium lanthanum zirconium oxide doped with copper and an element X, where X is selected from gallium (Ga), tantalum (Ta), strontium (Sr), barium (Ba), and aluminum (Al), and a > 0 and b > 0. Preferably, a + b = 0.25 to 0.8, and a > 0.1. Although the technique of doping LLZO with copper is very difficult, it results in a more stable overall structure, smoother lithium ion channels, and significantly lower manufacturing costs. Furthermore, it reduces the formation of lithium carbonate (Li2CO3) when the LLZO particles 24 are exposed to air.

[0020] In each of the composite NCM particles 20, the ratio of the total weight of the corresponding plurality of LLZO microparticles 24 to the weight of the corresponding NCM particle 250 having the glass phase is in the range of 0.2% to 2%.

[0021] <Process 520> Next, a carbon material mixture of a plurality of the composite NCM particles 20, a plurality of carbon nanotubes (CNTs) 30, and a plurality of nanoscale amorphous carbons 35 is performed to form a positive electrode particle 300 coated with a plurality of carbon materials. There are two methods for mixing the carbon materials, which will be described below.

[0022] <The first mixing method for mixing the carbon material is step 520A> A plurality of the composite NCM particles 20, a plurality of the carbon nanotubes 30, and a plurality of the nanoscale amorphous carbons 35 are simultaneously added to a dry mixer (e.g., a planetary mixer or a tumbler mixer) and mixed to form a plurality of the carbon material-coated positive electrode particles 300. Each of the carbon material-coated positive electrode particles 300 includes a corresponding composite NCM particle 20, and a corresponding plurality of the carbon nanotubes 30 and a corresponding plurality of the nanoscale amorphous carbons 35 coat the exterior of the corresponding composite NCM particle 20 (see FIG. 2). The stirring rotation speed of the dry mixer 55 is in the range of 50 rpm to 500 rpm, and the stirring time is in the range of 2 hours to 8 hours.

[0023] Preferably, the nanoscale amorphous carbon 35 is amorphous carbon of super P conductive additive. The size of each of the nanoscale amorphous carbon 35 ranges from 20 nm to 100 nm. Each of the nanoscale amorphous carbon 35 is mainly located in the gap formed by the intersection of the corresponding plurality of carbon nanotubes 30 (see FIG. 2). In each of the carbon material-coated positive electrode particles 300, the ratio of the total weight of the corresponding plurality of nanoscale amorphous carbon 35 to the weight of the corresponding composite NCM particle 20 ranges from 0.1% to 2%.

[0024] <The second mixing method for mixing the carbon material is step 520B> First, a plurality of the carbon nanotubes 30 and a plurality of the composite NCM particles 20 are mixed a first time, and then a plurality of the nanoscale amorphous carbons 35 are added and mixed a second time to form a plurality of the carbon material-coated positive electrode particles 300. Each of the carbon material-coated positive electrode particles 300 includes a corresponding composite NCM particle 20, and the corresponding plurality of carbon nanotubes 30 and plurality of nanoscale amorphous carbons 35 coat the exterior of the corresponding composite NCM particle 20. The first and second mixing methods are dry ball mill mixing or wet ball mill mixing.

[0025] When the first and second mixing steps are performed by dry ball milling, the carbon nanotubes 30 and the composite NCM particles 20 are first added to a dry ball mill, and the first mixing step is performed by ball milling. Then, the nanoscale amorphous carbon particles 35 are added to the dry ball mill, and the second mixing step is performed by ball milling to form the carbon material-coated cathode particles 300. In the first and second mixing steps, the rotation speed of the dry ball mill is between 50 rpm and 1000 rpm, the mixing time is between 20 minutes and 12 hours, and the ball milling is performed at room temperature of 50°C.

[0026] When the first and second mixing steps are wet ball mill mixing, the carbon nanotubes 30 are first dispersed in a dispersant and then introduced into a wet ball mill together with the composite NCM particles 20. The first mixing step is performed using the wet ball mill. Then, the nanoscale amorphous carbons 35 are added to the wet ball mill. The second mixing step is performed using the wet ball mill to form the carbon material-coated cathode particles 300. During the first and second mixing steps, the rotation speed of the wet ball mill is between 50 rpm and 500 rpm, and the mixing time is between 20 minutes and 12 hours. The dispersant is selected from polar and nonpolar non-aqueous organic solvents.

[0027] In step 520B, using any of the ball milling methods described above, a plurality of the carbon nanotubes 30 and a plurality of the composite NCM particles 20 are first mixed, and then a plurality of the nanoscale amorphous carbons 35 are added and mixed to form a plurality of positive electrode particles 300 coated with the carbon material.

[0028] In this way, the present invention achieves the above-mentioned carbon material mixing by the above-mentioned step 520A or step 520B.

[0029] The carbon nanotubes 30 include a plurality of short-chain carbon nanotubes 32 and a plurality of long-chain carbon nanotubes 34, each of which has a length ranging from 0.5 μm to 1 μm, and each of which has a length ranging from 3 μm to 8 μm. In each of the carbon material-coated positive electrode particles 300, the ratio of the total weight of the corresponding carbon nanotubes 30 to the weight of the corresponding composite NCM particle 20 is between 0.1% and 2%.

[0030] The carbon nanotubes 30 can bridge the composite NCM particles 20 with different numbers of layers. The more carbon nanotubes 30 added, the higher the conductivity of the composite NCM particles 20. Each of the short-chain carbon nanotubes 32 is used to bridge the corresponding LLZO microparticles 24 and the corresponding NCM large particles 22 (see FIGS. 5 and 6). Each of the long-chain carbon nanotubes 34 is used to coat the corresponding composite NCM particle 20. The carbon nanotubes 30 are very conductive materials, and when attached to the corresponding composite NCM particle 20, they form a furball-like shape (see FIG. 2).

[0031] The carbon nanotubes 30 are used to increase the electrical conductivity of electrons. That is, they form conductive bridges around the different LLZO particles 24, enabling electron conduction in each of the composite NCM particles 20. The carbon nanotubes 30 are randomly distributed on the surface of the corresponding composite NCM particle 20. Because carbon nanotubes have extremely high electrical conductivity, the carbon nanotubes 30 enable electron conduction between the different LLZO particles 24 and the NCM large particles 22, thereby increasing the electrical conductivity of the entire positive electrode 100.

[0032] The plurality of nanoscale amorphous carbons 35 and the plurality of carbon nanotubes 30 act as conductive additives. Each of the nanoscale amorphous carbons 35 has a particle shape, and each of the carbon nanotubes 30 has an elongated shape. Gaps are formed between the carbon nanotubes 30 that intersect vertically and horizontally on the composite NCM particle 20, and current does not pass through these gaps. Therefore, the corresponding nanoscale amorphous carbons 35 are added to these gaps, and the bridging of the nanoscale amorphous carbons 35 enables charge conduction between different carbon nanotubes 30, further improving current transmission efficiency.

[0033] In each of the positive electrode particles 300 coated with the carbon material, the ratio of the total weight of the corresponding plurality of carbon nanotubes 30 and the corresponding plurality of nanoscale amorphous carbons 35 to the weight of the corresponding composite NCM particle 20 is (0.09~3):100.

[0034] In each of the carbon material-coated positive electrode particles 300, the weight ratio of the corresponding plurality of carbon nanotubes 30, the corresponding plurality of nanoscale amorphous carbons 35, and the corresponding composite NCM particles 20 is 0.5:1:100.

[0035] After stirring and mixing by the above-mentioned steps 510 to 520, the size of each of the NCM large particles 22 ranges between 3 μm and 5 μm, the lateral size of each of the LLZO fine particles 24 ranges between 50 nm and 300 nm, and the size of each of the nanoscale amorphous carbon 35 ranges between 20 nm and 100 nm.

[0036] The advantage of using carbon nanotubes in the present invention is that lithium ions are easily stabilized between the carbon nanotubes 30, resulting in a solid and extremely abundant lithium ion cathode slurry of the present invention, and thus increased overall lithium ion conductivity. Furthermore, electrons are easily fixed between the short-chain carbon nanotubes 32, increasing overall lithium ion conductivity. Furthermore, the extremely high ion conductivity contributes to high-speed charging and discharging of the entire battery, further reducing the amount of cobalt used, and lowering overall manufacturing costs.

[0037] In the present invention, when a glassy phase material (i.e., a precursor of a glassy phase solid electrolyte) collides with the surface of a large NCM particle due to high-speed rotation, energy exchange occurs, forming a short-term high-temperature pulse, and the glassy phase material reacts to generate a glassy phase solid electrolyte, i.e., a glassy phase. This instantaneous high temperature only affects a small area, and the time is short, and the temperature drops quickly, so the performance of the material does not deteriorate due to prolonged exposure to high temperatures. Furthermore, by changing the process parameters, the process of the present invention can also be applied to oxide-based electrolytes.

[0038] Although the embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like are also included within the scope that does not deviate from the gist of the present invention. [Explanation of symbols]

[0039] 10 Positive substrate 12 Positive electrode slurry layer 14 Positive electrode slurry 20 Composite NCM particles 22 NCM large particles 24 LLZO fine particles 25 Glass phase 30 Carbon nanotubes 32 Short-chain carbon nanotubes 34 Long-chain carbon nanotubes 35 Nanoscale amorphous carbon 100 positive electrode 200 positive particles 250 NCM particles with glass phase 300 Positive electrode particles coated on carbon material

Claims

1. A method for producing NCM positive electrode particles coated with LLZO and a glass phase by a high-speed rotary process, the NCM positive electrode particles being used in a positive electrode of a solid-state battery or a battery of solid-state batteries, An NCM (lithium nickel manganese cobalt oxide) material is prepared, the NCM material being composed of a plurality of NCM large particles, each of which has an irregular cubic shape; the plurality of NCM large particles and a glass phase material are simultaneously introduced into a first agitator and sufficiently agitated at high speed to uniformly mix the plurality of NCM large particles and the glass phase material, thereby forming a plurality of NCM particles having a glass phase; each of the NCM particles having a glass phase contains a corresponding NCM large particle, and the exterior of the NCM large particle is formed of the glass phase material; The NCM large particles are coated with a glass phase formed of the glass phase material, and the glass phase material adheres to the entire or partial surface of each of the NCM large particles by the high-speed rotation of the first agitator, and the exterior of each of the NCM large particles is coated with the glass phase formed of the glass phase material. The glass phase is used to prevent the NCM large particles from directly contacting the electrolyte and suppress side reactions at the interface, and at the same time, it also reduces the interface resistance when lithium ions enter and exit the NCM large particles. The glass phase material has a lithium ion conductivity of 10 -5 Step A, which is composed of an amorphous oxide or non-oxide solid electrolyte having a conductivity greater than S / cm; A LLZO material is mixed with a plurality of NCM particles having the glass phase to form a plurality of composite NCM particles, wherein the size of each of the NCM large particles is larger than the size of each of the LLZO fine particles, and the LLZO material is composed of a plurality of LLZO fine particles, and each of the LLZO fine particles is lithium lanthanum zirconium oxide (Li 7 La 3 Zr 2 O 12 and step B of simultaneously introducing a plurality of NCM particles having the glass phase and the LLZO fine particles into a second agitator and thoroughly mixing them at high speed to mix them uniformly, and by the high speed rotation of the second agitator, each of the LLZO fine particles is distributed within or on the surface of the glass phase of a corresponding NCM particle having the glass phase, thereby forming corresponding composite NCM particles from each of the NCM particles having the glass phase and the corresponding LLZO fine particles.

2. The method for producing NCM positive electrode particles coated with LLZO and a glass phase using a high-speed rotation process, as described in claim 1, characterized in that the size of each of the NCM large particles is in the range of 3 μm to 5 μm, which is a single crystal structure, the thickness of the glass phase is in the range of 5 nm to 100 nm, and in step B, the maximum radial size of each of the LLZO fine particles is less than 40 nm.

3. 2. The method for preparing NCM positive electrode particles coated with LLZO and a glass phase by a high-speed rotation process according to claim 1, wherein in step A, the first agitator is selected from the group consisting of a 3D agitator, a flat roller agitator, and a DC blade agitator, and an anhydrous alcohol or isopropanol solvent is added to the DC blade agitator.

4. 2. The method for producing NCM positive electrode particles coated with LLZO and a glass phase by a high-speed rotation process according to claim 1, wherein in step A, the rotation speed of the first agitator is in the range of 50 rpm to 3000 rpm, and the agitation time is in the range of 10 minutes to 12 hours. To protect the large NCM particles from decomposition due to high temperature during high-speed rotation, oxygen or dry air is added during the mixing process of the first agitator, and the oxygen or dry air is added at a rate of 0.5 to 5 L / min.

5. 2. The method for producing NCM positive electrode particles coated with LLZO and a glass phase according to claim 1, wherein the glass phase material is composed of at least one element selected from the group consisting of an oxide of lithium and an element of Group IIIA, IVA, or VA, a lithium halide or lithium halo-oxide, lithium sulfide, an amorphous oxide-based solid electrolyte, an amorphous perovskite-based solid electrolyte, a garnet-based solid electrolyte, and lithium-phosphorus-oxygen-nitride.

6. 2. The method for producing NCM positive electrode particles coated with LLZO and a glass phase according to claim 1, wherein the glass phase material is composed of at least one of the following elements (A), (B), (C), (D), (E), and (F): (A) Li 2 O-RO x (wherein R is at least one element selected from boron (B), aluminum (Al), silicon (Si), germanium (Ge), phosphorus (P), and arsenic (As), and x=1 to 3). (B) Li-MO (wherein M is at least one element selected from the group consisting of fluorine (F), chlorine (Cl), bromine (Br), and iodine (I) halogens); (C) Li 2 SP 2 WITH 5 、 (D) Li-La-Ti-O (LLTO), (E) Li-La-Zr-O (LLZO), (F) LiPON (lithium phosphorus oxynitride).

7. 2. The method for producing NCM positive electrode particles coated with LLZO and a glass phase using a high-speed rotation process according to claim 1, wherein each of the LLZO fine particles is composed of at least one element selected from the group consisting of Ga-LLZO (Ga-doped LLZO, gallium-doped lithium lanthanum zirconium oxide), Cu-LLZO (Cu-doped LLZO, copper-doped lithium lanthanum zirconium oxide), Ta-LLZO (Ta-doped LLZO, tantalum-doped lithium lanthanum zirconium oxide), Sr-LLZO (Sr-doped LLZO, strontium-doped lithium lanthanum zirconium oxide), and Al-LLZO (Al-doped LLZO, aluminum-doped lithium lanthanum zirconium oxide).

8. Each of the LLZO particles is Cu a ,X b -LLZO, a ,X b LLZO is a lithium lanthanum zirconium oxide doped with copper and an element X, where X is selected from gallium (Ga), tantalum (Ta), strontium (Sr), barium (Ba), and aluminum (Al), and a>0 and b>0, preferably a+b=0.25-0.8, and a>0.

1. Although the technique of doping copper into LLZO is very difficult, the overall structure is more stable, the lithium ion channel is more smooth, and the manufacturing cost is very low. When the LLZO particles are exposed to air, lithium carbonate (Li 2 CO 3 2. The method for producing NCM positive electrode particles coated with LLZO and glass phases according to claim 1, characterized in that the formation of LLZO and glass phases is reduced.

9. The method for manufacturing NCM positive electrode particles coated with LLZO and a glass phase using a high-speed rotation process, as described in claim 1, characterized in that in each of the composite NCM particles, the ratio of the total weight of the corresponding plurality of LLZO microparticles to the weight of the corresponding NCM particle having the glass phase is in the range of 0.2% to 2%.

10. 2. The method for producing NCM positive electrode particles coated with LLZO and a glass phase according to claim 1, wherein in step B, the rotation speed of the second agitator is in the range of 50 rpm to 3000 rpm, and the agitation time is in the range of 10 minutes to 12 hours. Furthermore, oxygen or dry air is added during the mixing process of the second agitator at a rate of 0.5 to 5 L / min to protect the NCM large particles from being decomposed due to high temperature during high-speed rotation.

11. 2. The method for manufacturing NCM positive electrode particles coated with LLZO and a glass phase using a high-speed rotation process according to claim 1, further comprising a step C of forming positive electrode particles coated with a plurality of carbon materials by mixing a plurality of the composite NCM particles, a plurality of carbon nanotubes (CNTs), and a plurality of nanoscale amorphous carbons.

12. 12. The method for producing NCM positive electrode particles coated with LLZO and a glass phase by a high-speed rotation process according to claim 11, wherein the carbon material mixing comprises simultaneously feeding the plurality of composite NCM particles, the plurality of carbon nanotubes, and the plurality of nanoscale amorphous carbons into a dry mixer and mixing them to form a plurality of carbon material-coated positive electrode particles, each of the carbon material-coated positive electrode particles including a corresponding composite NCM particle, and the corresponding plurality of carbon nanotubes and nanoscale amorphous carbons coating the exterior of the corresponding composite NCM particle, the rotation speed of the dry mixer being in the range of 50 rpm to 500 rpm, and the stirring time being in the range of 2 hours to 8 hours.

13. 12. The method for manufacturing NCM positive electrode particles coated with LLZO and a glass phase using a high-speed rotation process according to claim 11, wherein the carbon material mixing comprises first mixing a plurality of the carbon nanotubes with a plurality of the composite NCM particles a first time, and then adding a plurality of the nanoscale amorphous carbons and mixing a second time to form a plurality of positive electrode particles coated with the carbon material, each of the carbon material-coated positive electrode particles comprising a corresponding composite NCM particle, and the corresponding plurality of carbon nanotubes and a corresponding plurality of nanoscale amorphous carbons coating the exterior of the corresponding composite NCM particle, and the first mixing and the second mixing are performed by dry ball milling or wet ball milling.

14. 14. The method for producing NCM positive electrode particles coated with LLZO and a glass phase by a high-speed rotation process according to claim 13, wherein the first mixing and the second mixing are dry ball mill mixing, and the plurality of carbon nanotubes and the plurality of composite NCM particles are first added to a dry ball mill to perform the first mixing using a ball mill, and then the plurality of nanoscale amorphous carbons are added to the dry ball mill to perform the second mixing using a ball mill to form the plurality of carbon material-coating positive electrode particles, and the first mixing and the second mixing are performed at a rotation speed of the dry ball mill ranging from 50 rpm to 1000 rpm, a mixing time ranging from 20 minutes to 12 hours, and the ball milling is performed at a room temperature of 50°C.

15. 14. The method for producing NCM positive electrode particles coated with LLZO and a glass phase by a high-speed rotation process according to claim 13, wherein the first mixing and the second mixing are wet ball mill mixing, the carbon nanotubes are first dispersed in a dispersant, and then the dispersed carbon nanotubes are introduced into a wet ball mill together with the composite NCM particles. The first mixing is performed using the wet ball mill, and then the nanoscale amorphous carbons are added to the wet ball mill. The second mixing is performed using the wet ball mill to form the carbon material-coating positive electrode particles. In the first mixing and the second mixing, the rotation speed of the wet ball mill is in the range of 50 rpm to 500 rpm, and the mixing time is in the range of 20 minutes to 12 hours. The dispersant is selected from polar and non-polar non-aqueous organic solvents.

16. The size of each of the nanoscale amorphous carbons is in the range of 20 nm to 100 nm, and each of the nanoscale amorphous carbons is located in a gap formed by the intersection of a corresponding plurality of carbon nanotubes; 12. The method for manufacturing NCM positive electrode particles coated with LLZO and glass phases using a high-speed rotation process, as described in claim 11, characterized in that, in each of the positive electrode particles coated with the carbon material, the ratio of the total weight of the corresponding plurality of nanoscale amorphous carbons to the weight of the corresponding composite NCM particles is in the range of 0.1% to 2%.

17. The method for manufacturing NCM positive electrode particles coated with LLZO and a glass phase using a high-speed rotation process, as described in claim 11, characterized in that the plurality of carbon nanotubes include a plurality of short-chain carbon nanotubes and a plurality of long-chain carbon nanotubes, each of the short-chain carbon nanotubes having a length ranging from 0.5 μm to 1 μm, and each of the long-chain carbon nanotubes having a length ranging from 3 μm to 8 μm, each of the short-chain carbon nanotubes being used to bridge the corresponding LLZO fine particles and the corresponding NCM large particles, and each of the long-chain carbon nanotubes being used to coat the corresponding composite NCM particles.

18. 12. The method for manufacturing NCM positive electrode particles coated with LLZO and glass phases using a high-speed rotation process, as described in claim 11, characterized in that, in each of the positive electrode particles coated with the carbon material, the ratio of the total weight of the corresponding plurality of carbon nanotubes to the weight of the corresponding composite NCM particle is in the range of 0.1% to 2%.

19. 12. The method for manufacturing NCM positive electrode particles coated with LLZO and a glass phase by a high-speed rotation process according to claim 11, wherein, in each of the carbon material-coated positive electrode particles, the ratio of the total weight of the corresponding plurality of carbon nanotubes and the corresponding plurality of nanoscale amorphous carbons to the weight of the corresponding composite NCM particle is (0.09-3):

100.

20. 12. The method for manufacturing NCM positive electrode particles coated with LLZO and glass phases using a high-speed rotation process according to claim 11, wherein in each of the carbon material-coated positive electrode particles, the weight ratio of the corresponding plurality of carbon nanotubes, the corresponding plurality of nanoscale amorphous carbons, and the corresponding composite NCM particles is 0.5:1:100.

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