TW202046537A - Manufacturing method of positive electrode material for secondary battery - Google Patents

Abstract

A manufacturing method of a carbon-coated and fluorine-contained positive electrode material for a secondary battery is disclosed. The manufacturing includes steps of (a) providing a carbon-coated precursor and an alkali fluoride to form secondary particles; (b) providing a closed system having an accommodating space and filling the accommodating space with the secondary particles, wherein the secondary particles are filled in the accommodating space at a volume filling ratio of more than 30%; and (c) heating the closed system at a temperature ranged from 300 ° C to 900 ° C in a non-oxidizing environment to form the carbon-coated and fluorine-contained positive electrode material. By using a closed system to produce the carbon-coated and fluorine-contained positive electrode material for the secondary battery with the volume filling rate of more than 30%, a single crystal phase can be obtained. It benefits to improve the conversion rate and increase the production efficiency. Furthermore, it avoids the waste of materials or the problems of environmental pollution.

Description

Manufacturing method of cathode material for secondary battery

This case is about a battery material, especially a method for manufacturing a cathode material for a secondary battery, to produce a carbon-coated cathode material for a secondary battery containing fluorine.

Cathode materials for secondary batteries are the main materials that affect the performance of secondary batteries. At present, many different improvement schemes have been proposed for the cathode materials for secondary batteries in the market. Take the lithium vanadium fluoride phosphate (LiVPO ₄ F) material as an example, as an example of the cathode material for lithium secondary batteries. Because the lithium vanadium fluoride phosphate (LiVPO ₄ F) cathode material has high operating voltage characteristics, it is helpful for lithium secondary batteries Achieve high capacitance, high discharge power, and excellent long cycle life, while improving thermal stability and high temperature performance. In addition, there is a technology of forming carbon coating on the surface of lithium vanadium fluoride phosphate (LiVPO ₄ F) to further improve the characteristics of lithium vanadium fluoride phosphate (LiVPO ₄ F) cathode materials.

However, in the actual production process, lithium vanadium fluoride phosphate (LiVPO ₄ F) easily forms other impurity phases such as lithium vanadium phosphate (Li ₃ V ₂ (PO ₄ ) ₃ ) during carbon coating treatment, and a single The pure-phase carbon-coated lithium vanadium fluoride phosphate (LiVPO ₄ F/C) cathode material affects the characteristics of subsequent battery applications.

In view of this, it is really necessary to provide a method for manufacturing a cathode material for a secondary battery to produce a carbon-coated cathode material for a fluorine-containing secondary battery, and to solve the problems faced by the prior art.

The purpose of this case is to provide a method for manufacturing a cathode material for secondary batteries to produce a carbon-coated and fluorine-containing cathode material for secondary batteries. The production of carbon-coated and fluorine-containing cathode materials for secondary batteries through a closed system can help improve product conversion and production efficiency, and avoid material waste or environmental pollution problems. The whole production process has simple technology and low production cost. The obtained carbon-coated and fluorine-containing cathode material for secondary batteries has a single crystal phase in X-ray diffraction analysis (XRD) analysis, which helps secondary batteries to achieve high capacity , High discharge power, excellent long cycle life, while improving thermal stability and high temperature performance.

Another purpose of this case is to provide a method for manufacturing a cathode material for a secondary battery to produce a carbon-coated and fluorine-containing cathode material for a secondary battery. During the heat treatment in a closed system, the volume filling rate of the secondary particles of the carbon-coated precursor and the alkali metal-containing fluoride is greater than 30%, and the carbon-coated and fluorine-containing two with a single pure phase can be obtained Cathode materials for secondary batteries avoid waste of materials or environmental pollution problems. In addition, as the volume filling rate of the secondary particles of the carbon-coated precursor and the alkali metal-containing fluoride increases, in addition to ensuring that a single pure phase can be obtained, a carbon-coated and fluorine-containing cathode material for secondary batteries In addition, it increases production efficiency and effectively reduces production costs.

Another purpose of this case is to provide a method for manufacturing a cathode material for a secondary battery to produce a carbon-coated and fluorine-containing cathode material for a secondary battery. When heat-treating secondary particles with carbon-coated precursors and alkali metal-containing fluorides in a closed system, fluorine-containing compounds can be added to improve product conversion and production efficiency.

In order to achieve the foregoing objective, this case provides a method for manufacturing a cathode material for secondary batteries: (a) Provide a carbon-coated precursor and an alkali metal-containing fluoride to form a secondary particle; (b) Provide a The closed system has an accommodating space, and the secondary particles are filled in the accommodating space, wherein the volume filling rate of the secondary particles in the accommodating space is greater than 30%; and (c) in a non-oxidizing In the environment, heat treatment is performed at a temperature of 300°C to 900°C to produce the positive electrode material.

In one embodiment, the positive electrode material is selected from the group consisting of carbon-coated lithium vanadium fluoride phosphate (LiVPO ₄ F/C), carbon-coated lithium aluminum fluoride phosphate (LiAlPO ₄ F/C), and carbon-coated lithium vanadium phosphate (LiVPO ₄ F/C). Lithium manganese fluoride phosphate (LiMnPO ₄ F/C), lithium titanium fluoride phosphate with carbon coating (LiTiPO ₄ F/C), lithium cobalt fluoride phosphate with carbon coating (LiCoPO ₄ F/C), with carbon coating Lithium nickel fluoride phosphate (LiNiPO ₄ F/C), lithium zinc fluoride phosphate with carbon coating (LiZnPO ₄ F/C), lithium chromium fluoride phosphate with carbon coating (LiCrPO ₄ F/C), with carbon coating Coated sodium vanadium fluoride phosphate (NaVPO ₄ F/C), carbon-coated sodium aluminum fluoride phosphate (NaAlPO ₄ F/C), carbon-coated sodium manganese fluoride phosphate (NaMnPO ₄ F/C), with carbon sodium fluoride coated titanium phosphate (NaTiPO ₄ F / C), sodium fluorophosphate cobalt (NaCoPO ₄ F / C) having carbon-coated, carbon-coated with a nickel phosphate, sodium fluoride (NaNiPO ₄ F / C), with Carbon-coated sodium zinc fluoride phosphate (NaZnPO ₄ F/C), carbon-coated sodium chromium fluoride phosphate (NaCrPO ₄ F/C), carbon-coated potassium vanadium fluoride phosphate (KVPO ₄ F/C), Potassium aluminum fluoride phosphate with carbon coating (KAlPO ₄ F/C), potassium manganese fluoride phosphate with carbon coating (KMnPO ₄ F/C), potassium titanium fluoride phosphate with carbon coating (KTiPO ₄ F/C) , Carbon-coated potassium cobalt fluoride phosphate (KCoPO ₄ F/C), carbon-coated potassium nickel fluoride phosphate (KNiPO ₄ F/C), carbon-coated potassium zinc fluoride phosphate (KZnPO ₄ F/C) ) And carbon-coated potassium chromium fluoride phosphate (KCrPO ₄ F/C).

In one embodiment, the carbon-coated precursor is selected from carbon-coated vanadium phosphate (VPO ₄ /C), carbon-coated aluminum phosphate (AlPO ₄ /C), and carbon-coated phosphoric acid Manganese (MnPO ₄ /C), titanium phosphate coated with carbon (TiPO ₄ /C), cobalt phosphate coated with carbon (CoPO ₄ /C), nickel phosphate coated with carbon (NiPO ₄ /C), carbon coated with zinc phosphate (ZnPO ₄ / C), and having carbon-coated chromium phosphate (CrPO ₄ / C) constitutes one of the groups.

In one embodiment, the alkali metal-containing fluoride is selected from one of the group consisting of lithium fluoride (LiF), sodium fluoride (NaF), and potassium fluoride (KF).

In one embodiment, the molar ratio of the carbon-coated precursor to the alkali metal-containing fluoride ranges from 1:1.0 to 1:1.05.

In one embodiment, step (a) uses mixing, slurrying and spray granulation to form secondary particles.

In one embodiment, the average particle size of the secondary particles ranges from 5um to 30um.

In one embodiment, step (b) further includes step (b1) to provide a fluorine-containing compound to fill the containing space.

In one embodiment, the fluorine-containing compound is selected from one of the group consisting of polyvinylidene difluoride (PVDF) and polytetrafluoroethylene (PTFE).

In one embodiment, the molar ratio of the fluorine-containing compound to the alkali metal-containing fluoride ranges from 0:1 to 0.1:1.

In one embodiment, the non-oxidizing environment is an argon atmosphere or a nitrogen atmosphere.

Some typical embodiments embodying the features and advantages of this case will be described in detail in the following description. It should be understood that this case can have various changes in different aspects, all of which do not depart from the scope of the case, and the descriptions and drawings therein are essentially for illustrative purposes, not for limiting the case.

FIG. 1 is a flow chart of the manufacturing method of the cathode material for the secondary battery according to the first preferred embodiment of the present application. Fig. 2 is a schematic diagram showing a closed system accommodating secondary particles in a preferred embodiment of this case. It should be noted that the manufacturing method of the positive electrode material for the secondary battery in this case is used to produce a carbon-coated and fluorine-containing positive electrode material for the secondary battery. The secondary battery is, for example, but not limited to, a lithium secondary battery, a sodium secondary battery, a potassium secondary battery or an alkali metal secondary battery composed of an alloy thereof. In this embodiment, the positive electrode material for the secondary battery with carbon coating and containing fluorine can be selected from, for example, lithium vanadium fluoride phosphate (LiVPO ₄ F/C) with carbon coating and lithium fluorine phosphate with carbon coating. Aluminum (LiAlPO ₄ F/C), carbon-coated lithium manganese fluoride phosphate (LiMnPO ₄ F/C), carbon-coated lithium titanium fluoride phosphate (LiTiPO ₄ F/C), carbon-coated fluorine phosphate Lithium cobalt (LiCoPO ₄ F/C), carbon-coated lithium nickel fluoride phosphate (LiNiPO ₄ F/C), carbon-coated lithium zinc fluoride phosphate (LiZnPO ₄ F/C), carbon-coated phosphoric acid Fluorolithium chromium (LiCrPO ₄ F/C), carbon-coated sodium vanadium fluoride phosphate (NaVPO ₄ F/C), carbon-coated sodium aluminum fluoride phosphate (NaAlPO ₄ F/C), carbon-coated sodium vanadium phosphate (NaAlPO ₄ F/C), Sodium manganese fluoride phosphate (NaMnPO ₄ F/C), sodium titanium fluoride phosphate with carbon coating (NaTiPO ₄ F/C), sodium cobalt fluoride phosphate (NaCoPO ₄ F/C) with carbon coating, with carbon coating Sodium nickel fluoride phosphate (NaNiPO ₄ F/C), sodium zinc fluoride phosphate with carbon coating (NaZnPO ₄ F/C), sodium chromium fluoride phosphate with carbon coating (NaCrPO ₄ F/C), with carbon coating Coated potassium vanadium fluoride phosphate (KVPO ₄ F/C), carbon-coated potassium aluminum fluoride phosphate (KAlPO ₄ F/C), carbon-coated potassium manganese fluoride phosphate (KMnPO ₄ F/C), with carbon Coated potassium titanium fluoride phosphate (KTiPO ₄ F/C), carbon-coated potassium cobalt fluoride phosphate (KCoPO ₄ F/C), carbon-coated potassium nickel fluoride phosphate (KNiPO ₄ F/C), Carbon-coated potassium zinc fluoride phosphate (KZnPO ₄ F/C) and carbon-coated potassium chromium fluoride phosphate (KCrPO ₄ F/C) are one of the groups. The manufacturing method of the cathode material for the secondary battery in this case includes the following steps.

First, in step S11, a carbon-coated precursor 11 and an alkali metal-containing fluoride 12 are provided to form primary particles 10. The carbon-coated precursor 11 can be selected from, for example, carbon-coated vanadium phosphate (VPO ₄ /C), carbon-coated aluminum phosphate (AlPO ₄ /C), and carbon-coated manganese phosphate (VPO ₄ /C). MnPO ₄ / C), with carbon-coated titanium phosphate (tiPO ₄ / C), with carbon-coated cobalt phosphate (CoPO ₄ / C), with carbon-coated nickel phosphate (NiPO ₄ / C), with carbon Coated zinc phosphate (ZnPO ₄ /C) and carbon-coated chromium phosphate (CrPO ₄ /C) constitute one of the group. The carbon-coated precursor 11 can be synthesized through, for example, solid-phase synthesis, but this case is not limited to this. The alkali metal-containing fluoride 12 can be selected from one of the group consisting of lithium fluoride (LiF), sodium fluoride (NaF), and potassium fluoride (KF), for example. It should be noted that the sources of the carbon-coated precursor 11 and the alkali metal-containing fluoride 12 do not limit the formation of the secondary particles 10. In this embodiment, the molar ratio of the carbon-coated precursor 11 to the alkali metal-containing fluoride 12 ranges from 1:1.0 to 1:1.05. The molar ratio of the carbon-coated precursor 11 to the alkali metal-containing fluoride 12 according to the dosage ratio ranges from 1:1.0 to 1:1.05, which can be formed by mixing, pulping and spray granulation Secondary particles 10. In this embodiment, the average particle size of the secondary particles ranges from 5um to 30um.

Next, in step S12, a closed system 2 is provided, which has an accommodating space 20, and the accommodating space 20 is filled with secondary particles 10. The closed system 2 can be, for example, a closed tank, and the filling of the closed system 2 can be, for example, operated in a glove box in a non-oxidizing environment, and this case is not limited to this. The volume filling rate of the secondary particles 10 in the accommodating space 20 is greater than 30%. As the volume filling rate of the secondary particles 10 of the carbon-coated precursor 11 and the alkali metal-containing fluoride 12 increases, it can increase Production efficiency, reduce production costs.

Finally, in step S13, the closed system 2 is maintained in a non-oxidizing environment, such as an argon atmosphere or a nitrogen atmosphere, and heat-treated at a temperature of 300°C to 900°C to obtain a single pure phase with carbon Coated and fluorine-containing cathode material for secondary batteries. Since the closed system 2 is used for production, in addition to improving the product conversion rate and production efficiency, it can also avoid the waste of materials or the problem of environmental pollution. In addition, as the volume filling rate of the secondary particles 10 of the carbon-coated precursor 11 and the alkali metal-containing fluoride 12 increases, in addition to ensuring that a single pure phase can be obtained for a carbon-coated and fluorine-containing secondary battery In addition to using positive electrode materials, production efficiency is increased and production costs are effectively reduced.

In a first example, 1.0 mol of VPO ₄ /C and 1.05 mol of LiF are taken, and the secondary particles 10 are formed by mixing, slurrying, and spraying granulation. Figure 3 shows the results of the particle size analysis of the secondary particles in the first example of this case. In this example, the average particle size of the secondary particles 10 is 27 μm, and the tap density is 1.3 g/cm ³ . The surface area of the secondary particles 10 measured by BET is 24 m ² /g. Next, in a non-oxidizing environment such as an argon (Ar) atmosphere or a nitrogen (N ₂ ) atmosphere, the secondary particles 10 are filled into, for example, a can body and the opening of the can body is closed to form a closed system 2. In the accommodating space 20 of the closed system 2, the volume filling rate of the secondary particles 10 is 30%. The closed system 2 containing the secondary particles 10 is placed in a high temperature furnace for heat treatment. In this example, the closed system 2 is maintained in a non-oxidizing environment, and the temperature is raised to 700°C at a temperature rise rate of 5°C per minute. After holding the temperature at 700°C for 2 hours, it is cooled to room temperature in a natural furnace. Then the secondary particles 10 in the density system 2 form a carbon-coated and fluorine-containing cathode material for secondary batteries LiVPO ₄ F/C. Figure 4 shows the XRD analysis results of the carbon-coated and fluorine-containing cathode material for secondary batteries obtained in the first example of this case. LiVPO ₄ F/C, a cathode material for secondary batteries coated with carbon and containing fluorine, forms a single crystal phase.

In a second example, 1.0 mol of VPO ₄ /C and 1.0 mol of LiF are used to form secondary particles by mixing, slurrying, and spraying granulation. Figure 5 shows the results of the particle size analysis of the secondary particles in the second example of this case. In this example, the average particle size of the secondary particles 10 is 7 μm, and the tap density is 1.2 g/cm ³ . The surface area of the secondary particles 10 measured by BET is 19 m ² /g. Next, in a non-oxidizing environment such as an argon atmosphere or a nitrogen atmosphere, the secondary particles 10 are filled into, for example, a tank body and the tank body opening is closed to form a closed system 2. In the accommodating space 20 of the closed system 2, the volume filling rate of the secondary particles 10 is 30%. The closed system 2 containing the secondary particles 10 is placed in a high temperature furnace for heat treatment. In this example, the closed system 2 in a non-oxidizing environment is heated to 700°C at a temperature rise rate of 5°C per minute. After holding the temperature at 700°C for 2 hours, it is naturally cooled. Then the secondary particles 10 in the density system 2 form a carbon-coated and fluorine-containing cathode material for secondary batteries LiVPO ₄ F/C. Figure 6 shows the XRD analysis results of the carbon-coated and fluorine-containing cathode material for secondary batteries obtained in the second example of this case. LiVPO ₄ F/C, a cathode material for secondary batteries coated with carbon and containing fluorine, forms a single crystal phase.

Table 1 shows other examples. The secondary particles 10 with carbon-coated precursor 11 and alkali metal-containing fluoride 12 are filled with a volumetric filling rate of more than 30%, and the temperature is between 300℃ and 900℃. A carbon-coated and fluorine-containing cathode material for secondary batteries obtained after heat treatment. Table 1 Precursor with carbon coating 11 Fluoride containing alkali metal 12 Cathode material for secondary battery with carbon coating and fluorine AlPO ₄ /C LiF LiAlPO ₄ F/C MnPO ₄ /C LiF LiMnPO ₄ F/C TiPO ₄ /C LiF LiTiPO ₄ F/C CoPO ₄ /C LiF LiCoPO ₄ F/C NiPO ₄ /C LiF LiNiPO ₄ F/C ZnPO ₄ /C LiF LiZnPO ₄ F/C CrPO ₄ /C LiF LiCrPO ₄ F/C VPO ₄ /C NaF NaVPO ₄ F/C AlPO ₄ /C NaF NaAlPO ₄ F/C MnPO ₄ /C NaF NaMnPO ₄ F/C TiPO ₄ /C NaF NaTiPO ₄ F/C CoPO ₄ /C NaF NaCoPO ₄ F/C NiPO ₄ /C NaF NaNiPO ₄ F/C ZnPO ₄ /C NaF NaZnPO ₄ F/C VPO ₄ /C KF KVPO ₄ F/C AlPO ₄ /C KF KAlPO ₄ F/C MnPO ₄ /C KF KMnPO ₄ F/C TiPO ₄ /C KF KTiPO ₄ F/C CoPO ₄ /C KF KCoPO ₄ F/C NiPO ₄ /C KF KNiPO ₄ F/C ZnPO ₄ /C KF KZnPO ₄ F/C CrPO ₄ /C KF KCrPO ₄ F/C

It is worth noting that since this case uses a closed system 2 for heat treatment, during the process of forming products from the carbon-coated precursor 11 and the secondary particles 10 of the alkali metal-containing fluoride 12, the intermediate products can be prevented from dissipating Resulting in the formation of miscellaneous phases. Taking the carbon-coated and fluorine-containing cathode material LiVPO ₄ F/C for secondary batteries in the foregoing demonstration column as an example, the closed system 2 can prevent the escape of gas intermediate products such as vanadium fluoride (VF ₃ ) and avoid other such An impurity phase of lithium vanadium phosphate (Li ₃ V ₂ (PO ₄ ) ₃ ) is formed. And as the volume filling rate of the secondary particles 10 of the carbon-coated precursor 11 and the alkali metal-containing fluoride 12 increases, in addition to ensuring that a single pure phase can be obtained for a carbon-coated and fluorine-containing secondary battery Cathode materials increase production efficiency and effectively reduce production costs.

FIG. 7 is a flow chart of the manufacturing method of the cathode material for the secondary battery according to the second preferred embodiment of the present invention. Fig. 8 is a schematic diagram showing the closed system accommodating secondary particles and fluorine-containing compounds in the second preferred embodiment of the present application. In this embodiment, the closed system 2 and the secondary particles 10 are similar to the closed system 2 and the secondary particles 10 shown in Figures 1 to 2, and the same element numbers represent the same elements, structures, and functions. This will not be repeated here. First, in step S21, a carbon-coated precursor 11 and an alkali metal-containing fluoride 12 are provided to form the primary particles 10. The carbon-coated precursor 11 can be synthesized by a solid-phase method, but this case is not limited to this. Of course, the sources of the carbon-coated precursor 11 and the alkali metal-containing fluoride 12 do not limit the formation of the secondary particles 10. Different from the closed system 2 and the secondary particles 10 shown in FIG. 1 to FIG. 2, in this embodiment, a fluorine-containing compound 30 is further provided in step S22. In this embodiment, the fluorine-containing compound 30 may be selected from one of the group consisting of polyvinylidene difluoride (PVDF) and polytetrafluoroethylene (PTFE), for example. The molar ratio of the fluorine-containing compound 30 to the alkali metal-containing fluoride 12 ranges from 0:1 to 0.1:1. Next, in step S23, a closed system 2 is provided, which has an accommodating space 20, and the accommodating space 20 is filled with secondary particles 10 and a fluorine-containing compound 30, wherein the secondary particles 10 are in the volume of the accommodating space 20 The filling rate is more than 30%. Finally, in step S24, in a non-oxidizing environment such as an argon atmosphere or a nitrogen atmosphere, the closed system 2 is heat-treated at a temperature of 300°C to 900°C to obtain a single pure phase with carbon coating and Cathode material for fluorine-containing secondary batteries. Since the cathode material for the secondary battery coated with carbon and fluorine in this case is produced in a closed system 2, and a fluorine-containing compound 30 is added to the closed system 2 to fill the accommodating space 20 to increase the closed system 2 in During the heat treatment, for example, the vapor pressure of the vanadium fluoride (VF ₃ ) gas makes the reaction more conducive to the formation of a carbon-coated and fluorine-containing cathode material for secondary batteries with a single crystal phase LiVPO ₄ F/C. It should be noted that the addition of the fluorine-containing compound can be adjusted according to actual application requirements. In other embodiments, it can be used in the process of forming the secondary particles 10 with a carbon-coated precursor 11 and an alkali metal-containing fluoride 12 In addition, this case is not limited to this, and will not repeat it.

In summary, this case provides a method for manufacturing a cathode material for a secondary battery to produce a carbon-coated and fluorine-containing cathode material for a secondary battery. The production of carbon-coated and fluorine-containing cathode materials for secondary batteries through a closed system can help improve product conversion and production efficiency, and avoid material waste or environmental pollution problems. The whole production process has simple technology and low production cost. The obtained carbon-coated and fluorine-containing cathode material for secondary batteries has a single crystal phase in the XRD analysis, which helps the secondary battery achieve high capacity, high discharge power, and excellent long cycle life, while improving Thermal stability and high temperature performance, etc. In addition, during the heat treatment in a closed system, the volume filling rate of the secondary particles of the carbon-coated precursor and the alkali metal-containing fluoride is greater than 30%, and a single pure phase of carbon-coated and fluorine-containing can be obtained The cathode material for secondary battery avoids the waste of materials or the problem of environmental pollution. As the volume filling rate of the secondary particles of the carbon-coated precursor and the alkali metal-containing fluoride increases, in addition to ensuring that a single pure phase of the carbon-coated and fluorine-containing secondary battery cathode material can be obtained, It also increases production efficiency and effectively reduces production costs. On the other hand, in this case, when the carbon-coated precursor and the secondary particles of alkali metal-containing fluoride are heat-treated in a closed system, fluorine-containing compounds can be added to improve the product conversion rate and production efficiency.

This case can be modified in many ways by those who are familiar with this technology, but it is not deviated from the protection of the patent application.

10: Secondary particles 11: Precursor with carbon coating 12: Fluoride containing alkali metals 2: Closed system 20: Housing space 30: Fluorinated compounds S11~S13: steps S21~S24: steps

FIG. 1 is a flow chart of the manufacturing method of the cathode material for the secondary battery according to the first preferred embodiment of the present application. Figure 2 is a schematic diagram showing the closed system accommodating secondary particles in the first preferred embodiment of the present invention. Figure 3 shows the results of the particle size analysis of the secondary particles in the first example of this case. Figure 4 shows the XRD analysis results of the carbon-coated and fluorine-containing cathode material for secondary batteries obtained in the first example of this case. Figure 5 shows the results of the particle size analysis of the secondary particles in the second example of this case. Figure 6 shows the XRD analysis results of the carbon-coated and fluorine-containing cathode material for secondary batteries obtained in the second example of this case. FIG. 7 is a flow chart of the manufacturing method of the cathode material for the secondary battery according to the second preferred embodiment of the present invention. Fig. 8 is a schematic diagram showing the closed system accommodating secondary particles and fluorine-containing compounds in the second preferred embodiment of the present application.

S11~S13: steps

Claims (11)

A manufacturing method of cathode material for secondary battery: (a) Provide a carbon-coated precursor and an alkali metal-containing fluoride to form primary and secondary particles; (b) Provide a closed system with an accommodating space, and fill the secondary particles in the accommodating space, wherein the volume filling rate of the secondary particles in the accommodating space is greater than 30%; and (c) Heat treatment in a non-oxidizing environment at a temperature of 300°C to 900°C to produce the cathode material. The method for manufacturing a positive electrode material for a secondary battery according to claim 1, wherein the positive electrode material is selected from the group consisting of carbon-coated lithium vanadium fluoride phosphate, carbon-coated lithium fluoride aluminum phosphate, and carbon-coated phosphoric acid Fluorolithium manganese, fluorolithium titanium phosphate with carbon coating, fluorolithium cobalt phosphate with carbon coating, fluorolithium nickel phosphate with carbon coating, fluorolithium zinc phosphate with carbon coating, and phosphoric acid with carbon coating Fluorolithium chromium, fluorosodium vanadium phosphate with carbon coating, sodium fluoride aluminum phosphate with carbon coating, sodium manganese fluoride phosphate with carbon coating, sodium titanium fluoride phosphate with carbon coating, phosphoric acid with carbon coating Sodium fluoride cobalt, sodium nickel fluoride phosphate with carbon coating, sodium zinc fluoride phosphate with carbon coating, sodium chromium fluoride phosphate with carbon coating, potassium fluoride vanadium phosphate with carbon coating, phosphoric acid with carbon coating Potassium fluoride aluminum, potassium fluoride manganese phosphate with carbon coating, potassium fluoride titanium phosphate with carbon coating, potassium fluoride cobalt phosphate with carbon coating, potassium fluoride nickel phosphate with carbon coating, phosphoric acid with carbon coating One of the group consisting of potassium fluoride zinc and potassium fluoride chromium phosphate coated with carbon. The method for manufacturing a cathode material for a secondary battery according to claim 1, wherein the carbon-coated precursor is selected from the group consisting of carbon-coated vanadium phosphate, carbon-coated aluminum phosphate, and carbon-coated aluminum phosphate One of the group consisting of manganese phosphate, carbon-coated titanium phosphate, carbon-coated cobalt phosphate, carbon-coated nickel phosphate, carbon-coated zinc phosphate, and carbon-coated chromium phosphate . The method for producing a positive electrode material for a secondary battery according to claim 1, wherein the alkali metal-containing fluoride is selected from one of the group consisting of lithium fluoride, sodium fluoride, and potassium fluoride. The method for manufacturing a cathode material for a secondary battery according to claim 1, wherein the molar ratio of the carbon-coated precursor to the alkali metal-containing fluoride ranges from 1:1.0 to 1:1.05. The method for manufacturing a positive electrode material for a secondary battery according to claim 1, wherein the step (a) is to form the secondary particles by mixing, slurrying and spray granulation. The method for manufacturing a positive electrode material for a secondary battery according to claim 1, wherein the average particle size of the secondary particles ranges from 5um to 30um. The method for manufacturing a positive electrode material for a secondary battery according to claim 1, wherein the step (b) further includes the step (b1) to provide a fluorine-containing compound to fill the containing space. The method for manufacturing a positive electrode material for a secondary battery according to claim 8, wherein the fluorine-containing compound is selected from one of the group consisting of polyvinylidene fluoride and polytetrafluoroethylene. The method for manufacturing a positive electrode material for a secondary battery according to claim 8, wherein the molar ratio of the fluorine-containing compound to the alkali metal-containing fluoride ranges from 0:1 to 0.1:1. The method for producing a cathode material for a secondary battery according to claim 1, wherein the non-oxidizing environment is an argon atmosphere or a nitrogen atmosphere.

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