Manufacturing method for lithium-ion battery cathode material

Abstract

The present invention provides a method for producing a lithium ion battery cathode material, in which elemental lithium is uniformly distributed in the lithium ion battery cathode material. In a method for producing a lithium ion battery cathode material, the method includes a Couette-Taylor reaction operation and a calcination operation. The Couette-Taylor reaction operation includes forming a product stream including a cathode material precursor by feeding a first reaction liquid and a second reaction liquid, respectively, to a Taylor-Couette flow apparatus. The first reaction liquid is a multi-metallic solution including a nickel compound, a cobalt compound, and a manganese compound. The second reaction liquid is a lithium source metal solution including a lithium compound. The cathode material precursor includes elemental lithium. The calcination operation includes calcining the cathode material precursor in a high temperature tubular furnace to obtain a cathode material.

Description

[Technical field]

[0001] The present invention relates to a method for making cathode materials, and in particular to a method for making lithium-ion battery cathode materials. [Background technology]

[0002] Nickel-rich ternary or quaternary cathode materials have the advantages of high energy density and low cost, and are currently the mainstream cathode materials for lithium-ion batteries. The manufacturing method includes synthesizing a cathode material precursor by coprecipitation, then uniformly mixing it with lithium salt, and obtaining the cathode material by high-temperature solid-phase sintering, but the manufacturing process of this manufacturing method is complicated and the manufacturing cost is high.

[0003] Currently, the lithium salt is mainly mixed by a solid-solid pulverization mixing method, that is, the lithium salt is first put into a ball mill and pulverized by the ball mill, and then the pulverized and finely powdered lithium salt and the precursor are uniformly mixed in a mixer at a predetermined ratio and sintered.

[0004] Because of the large differences in specific gravity and particle size between the lithium salts and the precursors, it is difficult to achieve uniform mixing of the materials by this solid-state mechanical method, and as a result, the calcined oxide tends to be locally lithium-rich or locally lithium-deficient, leading to poor electrochemical performance and poor batch-to-batch stability of the product.

[0005] Therefore, it is an important task for this business to overcome the above-mentioned shortcomings by improving the reaction efficiency of the reactants through the improvement of the process and materials. Summary of the Invention [Problem to be solved by the invention]

[0006] The technical problem to be solved by the present invention is to address the shortcomings of the prior art by providing a method for producing a lithium ion battery cathode material, in which lithium element is uniformly distributed in the lithium ion battery cathode material. [Means for solving the problem]

[0007] In order to solve the above technical problems, one technical means adopted by the present invention provides a method for producing a lithium-ion battery cathode material, which includes: supplying a first reaction solution, which is a multimetallic solution containing a nickel (Ni) compound, a cobalt (Co) compound, and a manganese compound (Mn), to a Taylor-Couette flow apparatus; supplying a second reaction solution, which is a lithium source metal solution containing a lithium (Li) compound, to the Taylor-Couette flow apparatus to react with the first reaction solution, thereby forming a product stream containing a cathode material precursor having lithium element; and performing a calcination operation, which includes calcining the cathode material precursor separated from the product stream in a high-temperature tubular furnace to obtain a cathode material.

[0008] Preferably, the method for producing the lithium ion battery cathode material further comprises performing a purification operation after the Couette-Taylor reaction operation and prior to the calcination operation, comprising isolating a powder of the cathode material precursor by filtering and drying the product stream.

[0009] Preferably, in the second reaction solution, the lithium compound is at least one selected from the group consisting of lithium hydroxide (LiOH), lithium carbonate (Li2CO3), lithium acetate (CH3COOLi), lithium oxalate (Li2C2O4), lithium sulfate (Li2SO4), and lithium nitrate (LiNO3).

[0010] Preferably, in the first reaction solution, the nickel compound is nickel sulfate (NiSO4), the cobalt compound is cobalt sulfate (CoSO4), and the manganese compound is manganese sulfate (MnSO4).

[0011] Preferably, in the second reaction solution, the lithium compound is lithium hydroxide (LiOH).

[0012] Preferably, the lithium compound in the second reaction solution is a source of the lithium element in the cathode material precursor.

[0013] Preferably, in the Couette-Taylor reaction, the second reaction liquid controls the pH value of the reaction mixture of the first reaction liquid and the second reaction liquid to pH 10 to pH 12. Preferably, in the Couette-Taylor reaction, the reaction mixture does not contain sodium hydroxide (NaOH).

[0014] Preferably, the Couette-Taylor reaction operation further comprises feeding a chelating agent liquid, which is an aqueous ammonia solution, into the Taylor-Couette flow apparatus to mix with the reaction mixture.

[0015] Preferably, a first reaction liquid flow rate for supplying the first reaction liquid to the Taylor-Couette flow apparatus is 1.5 mL / min to 2.0 mL / min, a second reaction liquid flow rate for supplying the second reaction liquid to the Taylor-Couette flow apparatus is 2.3 mL / min to 3.0 mL / min, and the first reaction liquid flow rate:second reaction liquid flow rate (flow rate ratio) is 1:1.2 to 1:2.

[0016] Preferably, the cathode material precursor formed in the Couette-Taylor reaction operation is a hydroxide of a metal alloy, the metal alloy including nickel, cobalt, manganese, and lithium.

[0017] Preferably, the firing conditions for the firing step include introducing oxygen gas into the high-temperature tubular furnace, increasing the temperature to a first temperature of 120°C to 180°C, and heating the cathode material precursor for 1 hour to 3 hours, then increasing the temperature to a second temperature of 450°C to 550°C, and heating the cathode material precursor for 5 hours to 7 hours, and then increasing the temperature to a third temperature of 750°C to 850°C, and heating the cathode material precursor for 11 hours to 13 hours, thereby finally forming the cathode material.

[0018] Preferably, the method for preparing the lithium ion battery cathode material does not include mixing and ball milling the cathode material precursor with a solid lithium salt after the Couette-Taylor reaction operation and before the calcination operation. Effect of the Invention

[0019] As an advantageous effect of the present invention, the method for producing a lithium ion battery cathode material according to the present invention has the following technical features: "a Couette-Taylor reaction operation is carried out, which includes: supplying a first reaction solution, which is a polymetallic solution containing a nickel (Ni) compound, a cobalt (Co) compound, and a manganese compound (Mn), to a Taylor-Couette flow apparatus; and supplying a second reaction solution, which is a lithium source metal solution containing a lithium (Li) compound, to the Taylor-Couette flow apparatus, and reacting the second reaction solution with the first reaction solution to form a product stream containing a cathode material precursor having lithium element"; and "a calcination operation is carried out, which includes calcining the cathode material precursor separated from the product stream in a high-temperature tubular furnace to obtain a cathode material". By introducing the lithium source by coprecipitation, the lithium element is uniformly dispersed in the cathode material at the atomic level, the mixed arrangement of cations is reduced, and the regularity of the layered structure is improved.

[0020] In addition, the size of the cathode material particles is uniform, which effectively improves the durability and stability of the battery, achieving high gram capacity and capacity retention rate, while at the same time ensuring the safety of the material. [Brief description of the drawings]

[0021] [Figure 1] FIG. 1 is a schematic diagram of an apparatus for producing a cathode material precursor using Taylor-Couette reactors according to an embodiment of the present invention. [Diagram 2] 1 is a flow chart of a method for manufacturing a lithium-ion battery cathode material according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] In order to better understand the features and technical contents of the present invention, please refer to the following detailed description of the present invention and the accompanying drawings, which are provided for reference and explanation only and are not intended to limit the scope of the present invention.

[0023] Hereinafter, the "method of manufacturing a lithium ion battery cathode material" according to an embodiment of the present invention will be described in detail with reference to certain specific embodiments, and those skilled in the art will be able to understand the advantages and effects of the present invention based on the contents disclosed herein. The present invention can be implemented or applied in other different specific embodiments, and various modifications and changes can be made to each detail in the present specification based on different perspectives and applications without departing from the concept of the present invention. In addition, as described in advance, the accompanying drawings of the present invention are simple schematic illustrations and are not drawn based on actual size. The technical contents of the present invention will be described in more detail based on the following embodiments, but the disclosed contents do not limit the scope of protection of the present invention.

[0024] It should be understood that, although the present specification may use the terms "first", "second", "third" and the like to describe various elements or signals, these elements or signals are not limited by these terms. These terms are mainly used to distinguish one element from another element or one signal from another signal. In addition, the term "or" used in the present specification may include any one or more combinations of the associated listed items according to actual circumstances.

[0025] [Method of manufacturing lithium-ion battery cathode materials] As shown in FIGS. 1 and 2, in an embodiment of the present invention, a method for producing a lithium-ion battery cathode material is provided in which a Couette-Taylor reactor is used to produce a cathode active material precursor containing elemental lithium.

[0026] Thereafter, the cathode material precursor containing lithium element can be directly subjected to a calcination operation to form a lithium ion battery cathode material directly, without the need to mix with other lithium salts.

[0027] The method according to the embodiment of the present invention can disperse lithium element in the lithium ion battery cathode material at the atomic level, thereby improving the situation of local excess or deficiency of lithium in the conventional technology, and improving the durability and stability of the lithium ion battery.

[0028] More specifically, the method for producing a lithium-ion battery cathode material according to an embodiment of the present invention includes steps S110, S120, and S130.

[0029] The step S110 is to carry out a Couette-Taylor reaction operation, which includes: supplying a first reaction solution L1 to a Taylor-Couette reactor 1 (e.g., a laminar continuous Taylor reactor, LCTR) by a first reaction solution supply unit 11; and supplying a second reaction solution L2 to the Taylor-Couette reactor 1 and carrying out a co-precipitation reaction to form a product stream P1 including a cathode material precursor having lithium element.

[0030] The first reaction liquid L1 is a multi-metal solution.

[0031] The multi-metal solution includes a nickel (Ni) compound, a cobalt (Co) compound, and a manganese (Mn) compound. In one embodiment of the present invention, the multi-metal solution may further include at least one of a magnesium (Mg) compound and an aluminum (Al) compound.

[0032] For example, the multi-metallic solution may be a nickel-cobalt-manganese multi-metallic solution, a nickel-cobalt-manganese-magnesium multi-metallic solution, or a nickel-cobalt-manganese-aluminum multi-metallic solution, but the invention is not limited thereto.

[0033] In one embodiment of the present invention, for example, the nickel compound may be nickel sulfate (NiSO4), the cobalt compound may be cobalt sulfate (CoSO4), the manganese compound may be manganese sulfate (MnSO4), the magnesium compound may be magnesium sulfate (MgSO4), and the aluminum compound may be (Al2(SO4)3), but the present invention is not limited thereto.

[0034] The second reaction liquid L2 is a lithium source metal solution. The lithium source metal solution contains a lithium (Li) compound.

[0035] In one embodiment of the present invention, the lithium compound is at least one selected from the group consisting of lithium hydroxide (LiOH), lithium carbonate (Li2CO3), lithium acetate (CH3COOLi), lithium oxalate (Li2C2O4), lithium sulfate (Li2SO4), and lithium nitrate (LiNO3).

[0036] Preferably, the lithium compound is lithium hydroxide (LiOH).

[0037] The second reaction liquid L2 contains a lithium (Li) compound used as a lithium element supply source of the cathode material precursor in the reaction system. The lithium (Li) compound (e.g., lithium hydroxide) in the second reaction liquid L2 is used as a precipitant, and is used instead of a conventional precipitant (i.e., sodium hydroxide, NaOH). The lithium (Li) compound can adjust the pH value of the reaction mixture, and is controlled to, for example, pH 10 to pH 12, and preferably pH 10.5 to pH 11.5.

[0038] Overall, an embodiment of the present invention provides a method for preparing a lithium-ion battery cathode material. In the process of preparing a precursor, a Taylor-Couette flow apparatus is used to co-precipitate a lithium compound with metal salts such as nickel, cobalt, and manganese. Alternatively, a composite cathode material can be prepared by first providing a polymetallic (e.g., nickel, cobalt, and manganese) solution to form a core of a polymetallic precursor, and then providing a lithium source metal solution. In the present invention, the lithium source is introduced by co-precipitation, so that the lithium element is uniformly dispersed in the cathode material at the atomic level, the mixed arrangement of cations is reduced, and the regularity of the layered structure is improved. In addition, the size of the generated particles is uniform, which effectively improves the durability and stability of the battery, while at the same time achieving high gram capacity and capacity retention, and simultaneously achieving the safety of the material.

[0039] More specifically, the Taylor-Couette flow device 1 includes a rotating shaft 1a and a reaction chamber 1b radially surrounding the rotating shaft 1a.

[0040] The starting position of the Taylor-Couette flow apparatus 1 (for example, the position on the left side of the Taylor-Couette flow apparatus 1 in Figure 1) is connected to the first reaction solution supply unit 11, the second reaction solution supply unit 12, and the chelating agent supply unit 13, respectively.

[0041] The Taylor-Couette flow apparatus 1 is axially connected to a rotary motor 14 of the rotating shaft 1a, and the rotary motor 14 drives the rotating shaft 1a to rotate along the axial direction. Here, the first reaction liquid supply unit 11 is arranged to supply the first reaction liquid L1 (e.g., nickel-cobalt-manganese multimetallic solution) to the reaction chamber 1b of the Taylor-Couette flow apparatus 1 through one pump injection unit 151 of a pump module 15.

[0042] Here, the second reaction liquid supply unit 12 is configured to supply a second reaction liquid L2 (e.g., a lithium source metal solution) to the reaction chamber 1b of the Taylor-Couette flow apparatus 1 via yet another pump injection unit 152 of the pump module 15, thereby mixing it with the first reaction liquid L1 to form a reaction mixture and to perform a co-precipitation reaction in the reaction chamber 1b.

[0043] Here, the chelating agent supply unit 13 is configured to supply a chelating agent liquid L3 (e.g., aqueous ammonia solution, NH4OH(aq)) to the reaction chamber 1b of the Taylor-Couette flow apparatus via yet another pump injection unit 153 of the pump module 15, thereby mixing the first reaction liquid L1 (e.g., nickel-cobalt-manganese multimetallic solution) and the second reaction liquid L2 (e.g., lithium source metal solution) to form a reaction mixture and chelate with those metal elements.

[0044] By driving the rotary motor 14 to rotate the rotating shaft 1a along the axial direction, a reaction mixture formed of a first reaction liquid L1 (e.g., a multi-metal solution), a second reaction liquid L2 (e.g., a lithium source metal solution), and a chelating agent liquid L3 (e.g., an aqueous ammonia solution) supplied to the reaction chamber 1b of the Taylor-Couette flow apparatus 1 can be completely reacted.

[0045] Lithium elements are dispersed in the cathode material precursor formed by the Couette-Taylor reaction, and the lithium elements are uniformly dispersed in the cathode material precursor at an atomic level.

[0046] In the Taylor-Couette reaction operation, the rear side of the outlet of the Taylor-Couette flow apparatus 1 (for example, the rear side of the right side of the Taylor-Couette flow apparatus 1 in FIG. 1 ) is connected to a pH value monitoring unit 16 for monitoring the pH value of the product flow P1 of the cathode material precursor.

[0047] In one embodiment of the present invention, in order to improve the reaction efficiency of the Taylor-Couette reaction operation, the reaction temperature of the Taylor-Couette flow apparatus 1 is preferably 50°C to 70°C, more preferably 55°C to 65°C.

[0048] The motor speed at which the rotary motor 14 drives the rotation of the rotary shaft 1a is preferably 500 rpm to 700 rpm, and more preferably 550 rpm to 650 rpm.

[0049] The flow rate of the first reaction liquid L1 (e.g., a multi-metal solution) supplied to the reaction chamber 1b of the Taylor-Couette flow apparatus 1 via the first reaction liquid supply unit 11 is preferably 1.5 mL / min to 2.0 mL / min, and more preferably 1.6 mL / min to 1.8 mL / min.

[0050] The second reaction solution L2 (e.g., lithium source metal solution) supplied to the reaction chamber 1b of the Taylor-Couette flow apparatus 1 via the second reaction solution supply unit 12 has a second reaction solution flow rate of preferably 2.3 mL / min to 3.0 mL / min, more preferably 2.5 mL / min to 2.7 mL / min. The second reaction solution flow rate is higher than the first reaction solution flow rate so as to provide a sufficient lithium source. In addition, the pH value of the product flow P1 is preferably controlled to pH10 to pH12 by the second reaction solution L2 (e.g., lithium source metal solution).

[0051] From another perspective, the flow rate ratio between the first reaction liquid flow rate and the second reaction liquid flow rate (first reaction liquid flow rate:second reaction liquid flow rate) is preferably 1:1.2 to 1:2, and more preferably 1:1.4 to 1:1.7.

[0052] Here, the total volume molar concentration of multiple metals (for example, nickel, cobalt, and manganese) in the first reaction liquid L1 is preferably 1.5M to 2.5M, and more preferably 1.8M to 2.2M.

[0053] Here, in the second reaction liquid L2, the concentration of the lithium (Li) compound (for example, lithium hydroxide) is preferably 4.5M to 5.3M, and more preferably 5M to 5.3M.

[0054] The flow rate of the chelating agent liquid L3 (e.g., an aqueous ammonia solution) supplied to the reaction chamber 1b of the Taylor-Couette flow apparatus 1 via the chelating agent supply unit 13 is preferably 0.4 mL / min to 0.8 mL / min, and more preferably 0.5 mL / min to 0.7 mL / min.

[0055] Furthermore, the residence time of the reaction mixture formed from the first reaction liquid L1 (e.g., a polymetal solution), the second reaction liquid L2 (e.g., a lithium source metal solution), and the chelating agent L3 (aqueous ammonia solution) in the Taylor-Couette flow apparatus 1 is preferably 172 minutes to 238 minutes, and more preferably 192 minutes to 217 minutes.

[0056] In the product stream P1, the average particle size (D50) of the cathode material precursor containing elemental lithium is preferably 5 μm to 15 μm, and more preferably 7 μm to 12 μm, although the present invention is not limited thereto.

[0057] The cathode material precursor is a hydroxide of a metal alloy in which a multi-metal element and a lithium element are combined. In one embodiment of the present invention, the cathode material precursor may be a nickel (Ni)-cobalt (Co)-manganese (Mn)-lithium (Li) alloy hydroxide, a nickel (Ni)-cobalt (Co)-manganese (Mn)-magnesium (Mg)-lithium (Li) alloy hydroxide, or a nickel (Ni)-cobalt (Co)-manganese (Mn)-aluminum (Al)-lithium (Li) alloy hydroxide, but the present invention is not limited thereto.

[0058] In this embodiment, the position where the second reaction liquid supply unit 12 injects the second reaction liquid L2 into the Taylor-Couette flow apparatus 1 and the position where the first reaction liquid supply unit 11 injects the first reaction liquid L1 into the Taylor-Couette flow apparatus 1 are radially symmetrical to each other so that the first reaction liquid L1 and the second reaction liquid L2 are in sufficient contact with each other, but the present invention is not limited to this.

[0059] It is worth noting that, in the parameters of the manufacturing conditions shown in this embodiment, the volume of the Taylor-Couette flow apparatus is 1 liter (L), but the present invention is not limited thereto. The volume of the Taylor-Couette flow apparatus can be expanded to 10 L to 1000 L for reaction, and the manufacturing conditions can be adjusted accordingly.

[0060] More specifically, step S120 is to perform a purification operation, which includes purifying a product stream P1 containing the cathode material precursor formed in the Taylor-Couette flow apparatus 1 to separate the cathode material precursor from the product stream P1.

[0061] More specifically, the purification step includes filtering the product stream P2 to obtain a cathode material precursor, and washing and drying the cathode material precursor to obtain a purified cathode material precursor. The cathode material precursor may be in a powder form, but the invention is not limited thereto.

[0062] Further, step S130 is to perform a calcination operation, which includes calcining the purified cathode material precursor using a high-temperature tubular furnace by introducing oxygen gas into the high-temperature tubular furnace to obtain nickel-rich and lithium-rich cathode materials, which can be used as cathode materials for lithium batteries.

[0063] Here, the firing conditions of the firing process are as follows: the oxygen gas in the high-temperature tubular furnace is heated to a first temperature of 120°C to 180°C, and the cathode material precursor is heated for 1 hour to 3 hours; then, the oxygen gas in the high-temperature tubular furnace is heated to a second temperature of 450°C to 550°C, and the cathode material precursor is heated for 5 hours to 7 hours; then, the oxygen gas in the high-temperature tubular furnace is heated to a third temperature of 750°C to 850°C, and the cathode material precursor is heated for 11 hours to 13 hours, thereby finally forming the nickel-rich and lithium-rich cathode materials; however, the firing process according to the present invention is not limited thereto.

[0064] It is noteworthy that in this embodiment, since the cathode material precursor formed in the Couette-Taylor reaction is a hydroxide of a metal alloy, the calcination step can be performed by calcining the purified cathode material precursor in a high-temperature tubular furnace, and can omit mixing and ball-milling the precursor with a solid lithium salt (e.g., solid lithium hydroxide).

[0065] According to the above-mentioned configuration, in an embodiment of the present invention, a new type of Taylor-Couette flow apparatus is adopted as a substitute for the conventional continuous stirring reactor to prepare the cathode material precursor by coprecipitation. By controlling the reaction temperature, rotation speed, and liquid flow rate, the particle size, crystallinity, and specific surface area of ​​the precursor can be controlled, which is suitable for industrial continuous production. In addition, in an embodiment of the present invention, instead of the conventional method of introducing the lithium source by mixing and grinding, a coprecipitation method is adopted to introduce the lithium source into the multimetallic precursor. Thereby, the lithium element can be uniformly dispersed at the atomic level, and the method according to the embodiment of the present invention has the advantage of being a simple process because the mixing and ball milling steps can be omitted.

[0066] [Advantageous Effects of the Embodiments] As an advantageous effect of the present invention, the method for producing a lithium ion battery cathode material according to the present invention includes the following technical features: "supplying a first reaction solution, which is a multimetallic solution containing a nickel (Ni) compound, a cobalt (Co) compound, and a manganese compound (Mn), to a Taylor-Couette flow apparatus; and supplying a second reaction solution, which is a lithium source metal solution containing a lithium (Li) compound, to the Taylor-Couette flow apparatus and reacting it with the first reaction solution to form a product stream containing a cathode material precursor having lithium element; and "performing a calcination operation, which includes calcining the cathode material precursor separated from the product stream in a high-temperature tubular furnace to obtain a cathode material." By introducing the lithium source by coprecipitation, the lithium element is uniformly dispersed in the cathode material at the atomic level, the mixed arrangement of cations is reduced, and the regularity of the layered structure is improved. In addition, the size of the cathode material particles is uniform, which effectively improves the durability and stability of the battery, and can achieve high gram capacity and capacity retention while simultaneously achieving the safety of the material.

[0067] The above disclosure is merely a preferred embodiment of the present invention, and the scope of the claims of the present invention is not limited thereto. Therefore, all equivalent technical modifications made by utilizing the specification and drawings of the present invention are included in the scope of the claims of the present invention. [Explanation of symbols]

[0068] 1...Taylor-Couette flow apparatus 1a...Rotation axis 1b...Reaction chamber 11...First reaction solution supply unit 12...Second reaction liquid supply unit 13...Chelating agent supply unit 14...Rotary motor 15...Pump module 151, 152, 153... Pump injection unit 16...pH value monitoring unit L1...First reaction solution L2...Second reaction mixture L3... Chelating agent liquid P1...Cathode material precursor

Claims

1. performing a Couette-Taylor reaction operation, the operation including: supplying a first reactant solution, the first reactant solution being a multi-metal solution including a nickel (Ni) compound, a cobalt (Co) compound, and a manganese (Mn) compound, to a Taylor-Couette flow apparatus; and supplying a second reactant solution, the second reactant solution being a lithium source metal solution including a lithium (Li) compound, to the Taylor-Couette flow apparatus to react with the first reactant solution to form a product stream including a cathode material precursor having a lithium element; and performing a calcination operation comprising calcining the cathode material precursor separated from the product stream in a high temperature tubular furnace to obtain a cathode material.

2. 10. The method of claim 1 further comprising performing a purification operation after the Couette-Taylor reaction operation and before the calcination operation, the purification operation comprising isolating a powder of the cathode material precursor by filtering and drying the product stream.

3. In the second reaction solution, the lithium compound is lithium hydroxide (LiOH), lithium carbonate (Li ２ CO ３ ), lithium acetate (CH ３ COOLi), lithium oxalate (Li ２ C ２ O ４ ), lithium sulfate (Li ２ SO ４ ), and lithium nitrate (LiNO ３ 2. The method of claim 1, wherein the cathode material is at least one selected from the group consisting of:

4. In the first reaction solution, the nickel compound is nickel sulfate (NiSO ４ ), and the cobalt compound is cobalt sulfate (CoSO ４ ), and the manganese compound is manganese sulfate (MnSO ４ 2. The method of claim 1, wherein the lithium ion battery cathode material is

5. 2. The method for producing a lithium ion battery cathode material according to claim 1, wherein in the second reaction solution, the lithium compound is lithium hydroxide (LiOH).

6. 6. The method of claim 5, wherein the lithium compound in the second reaction solution is a source of the lithium element in the cathode material precursor.

7. 7. The method for producing a lithium ion battery cathode material according to claim 6, wherein in the Couette-Taylor reaction, the pH value of the reaction mixture of the first reaction solution and the second reaction solution is controlled to pH 10 to pH 12 by the second reaction solution.

8. 8. The method for producing a lithium ion battery cathode material as claimed in claim 7, wherein in the Couette-Taylor reaction operation, the reaction mixture does not contain sodium hydroxide (NaOH).

9. 8. The method of claim 7, wherein the Couette-Taylor reaction operation further comprises: supplying a chelating agent solution, which is an aqueous ammonia solution, to the Taylor-Couette flow apparatus to mix with the reaction mixture.

10. 2. The method for producing a lithium ion battery cathode material according to claim 1, wherein a first reaction solution flow rate for supplying the first reaction solution to the Taylor-Couette flow apparatus is 1.5 mL / min to 2.0 mL / min, a second reaction solution flow rate for supplying the second reaction solution to the Taylor-Couette flow apparatus is 2.3 mL / min to 3.0 mL / min, and a ratio of the first reaction solution flow rate:the second reaction solution flow rate (flow rate ratio) is 1:1.2 to 1:

2.

11. 2. The method of claim 1, wherein the cathode material precursor formed in the Couette-Taylor reaction operation is a hydroxide of a metal alloy, the metal alloy including nickel, cobalt, manganese, and lithium.

12. 2. The method for producing a lithium ion battery cathode material according to claim 1, wherein the calcination conditions of the calcination operation are as follows: oxygen gas is introduced into the high temperature tubular furnace, and the temperature is increased to a first temperature of 120°C to 180°C to heat the cathode material precursor for 1 hour to 3 hours, then the temperature is increased to a second temperature of 450°C to 550°C to heat the cathode material precursor for 5 hours to 7 hours, and then the temperature is increased to a third temperature of 750°C to 850°C to heat the cathode material precursor for 11 hours to 13 hours to finally form the cathode material.

13. 2. The method of claim 1, wherein the method does not include mixing and ball milling the cathode material precursor with a solid lithium salt after the Couette-Taylor reaction operation and before the calcination operation.

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