Method and apparatus for preparing ternary precursors with different particle size distributions

Abstract

The application provides a preparation method of ternary precursors with different particle size distributions, comprising the following steps: a pretreatment stage of a coprecipitation reaction; S2, a coprecipitation reaction stage, comprising a crystal nucleus preparation stage and a crystal nucleus growth stage; and S3, a post-treatment stage of the coprecipitation reaction. The preparation method of the ternary precursors with different particle size distributions is characterized in that the coprecipitation reaction is carried out in a first reaction kettle and a second reaction kettle, the first reaction kettle is used for reaction crystallization, the second reaction kettle is used for a mother liquor cleaning operation, slurry is circulated, and particle size is synchronously increased. The preparation method is simple in operation, can improve production efficiency, and can more finely control particle size distribution by optimizing the process. The application further provides a device using the preparation method of the ternary precursors with different particle size distributions.

Description

Technical Field

[0001] This invention relates to the technical field of battery materials, and in particular to a method and apparatus for preparing ternary precursors with different particle size distributions. Background Technology

[0002] Compared with other rechargeable batteries, lithium-ion batteries have the advantages of high energy density and strong functionality, and therefore their use in various applications such as portable electric appliances and devices, electric vehicles and stationary energy storage systems is growing exponentially.

[0003] To meet diverse application needs, engineers are conducting more in-depth research into the characteristics of lithium-ion batteries to develop batteries with desired properties, such as greater capacity, higher energy density, longer lifespan, greater safety, and lower environmental impact. These characteristics of lithium-ion batteries are determined by the performance of the cathode, which in turn originates from the cathode precursor materials.

[0004] In terms of cathode precursor materials, layered nickel-manganese-cobalt-based materials are among the most attractive cathodes for lithium-ion batteries due to their high capacity, strong structural strength, and good thermal stability. These cathode precursor materials are nickel-manganese-cobalt hydroxide (ternary precursors), and their mainstream preparation method involves co-precipitation in a continuous stirred tank reactor (referred to as a reaction vessel).

[0005] Ternary precursors with different particle size distributions have different characteristics and their applications also differ. Ternary precursor samples with a wide particle size distribution have small interparticle gaps and high tap density, resulting in higher energy density in the cathode material. Ternary precursor samples with a narrow particle size distribution have limited tap density, but due to their uniform particle size and distribution, they can achieve higher power and exhibit better cycle performance.

[0006] Currently, there are three main methods for preparing ternary precursors using the co-precipitation method: continuous method, batch method, and semi-continuous method. Among them, the continuous method involves simultaneous feeding and product output, which has the characteristics of high production efficiency and wide particle size distribution. When the output is stable, the particle size distribution has a diameter range of 0.8-2.5 mm. However, this method requires a high level of operator skill.

[0007] The batch method involves continuously feeding raw materials into the reactor for reaction, and then unloading the slurry all at once once the required particle size is achieved. If, during the reaction, the reactor is full but the particle size is not yet within the acceptable range, the mother liquor must be discharged through filtration or sedimentation equipment to allow the solid particles to continue growing. This method produces samples with good uniformity and a narrow particle size distribution, with a diameter range generally between 0.3 and 0.6 mm, but its production efficiency is relatively low.

[0008] The semi-continuous process involves a continuous flow of raw materials into the reactor for reaction. Once the reactor is full, the overflow is processed; if the material meets the acceptable standards, it is transferred to a storage tank; otherwise, it overflows to other reactors for further reaction. Typically, a group of 3 to 6 continuous reactors forms an independent production system. This method is simple to control and has high production efficiency, producing samples with a wide particle size distribution, generally ranging from 0.5 to 0.9 mm in diameter. However, the semi-continuous process is limited by the solid content, and its yield is determined by the concentration and flow rate of salt and alkali, thus limiting its production capacity. Furthermore, compared to the batch process, the semi-continuous process offers a wider particle size distribution.

[0009] Therefore, it is necessary to improve the existing methods for preparing ternary precursors. Summary of the Invention

[0010] To address the aforementioned problems in existing technologies, this invention provides a method for preparing ternary precursors with different particle size distributions. A co-precipitation reaction is carried out in a first reactor and a second reactor. The first reactor performs reaction crystallization, while the second reactor performs mother liquor removal, allowing the slurry to circulate and the particle size to increase synchronously. This preparation method, through process optimization, simplifies operation, improves production efficiency, and enables more precise control of particle size distribution. This invention also provides an apparatus for applying this method for preparing ternary precursors with different particle size distributions.

[0011] To achieve the above objectives, the present invention provides the following technical solution:

[0012] A method for preparing ternary precursors with different particle size distributions includes the following steps:

[0013] S1. Pretreatment stage for coprecipitation reaction

[0014] Prepare a mixed salt solution of nickel, cobalt, and manganese, an aqueous solution of sodium hydroxide, and an aqueous solution of ammonia, respectively.

[0015] A mixed salt solution of nickel, cobalt, and manganese, an aqueous solution of sodium hydroxide, and an aqueous solution of ammonia were added to the first reaction vessel to form a coprecipitation reaction base liquid. The mixture was stirred under temperature control to ensure that the oxygen content of the reaction system was less than 3% by volume.

[0016] S2. Coprecipitation reaction stage, including nucleus preparation stage and nucleus growth stage;

[0017] In the crystal nucleus preparation stage, a mixed salt solution of nickel, cobalt, and manganese, an aqueous solution of sodium hydroxide, and an aqueous solution of ammonia are added to the first reaction vessel in parallel to prepare crystal nuclei.

[0018] During the crystal nucleus growth stage, the pH of the reaction system is controlled at 10.0-10.5, and the ammonium concentration is 5.0-8.0 g / L. After the liquid level in the first reactor reaches the overflow port, the slurry flows into the second reactor, and the slurry circulation between the first and second reactors begins. When the liquid level in the second reactor exceeds the filter rod, the mother liquor is drained until the particle size D50 of the ternary precursor grows to 5-15 μm.

[0019] S3. Post-precipitation treatment stage

[0020] The slurry is aged, washed, and dried. The dried material is then demagnetized, sieved, and packaged.

[0021] In one preferred embodiment, during the nucleus preparation stage of S2, a nickel-cobalt-manganese mixed salt solution, an aqueous sodium hydroxide solution, and an aqueous ammonia solution are added concurrently to the first reaction vessel, the pH of the reaction system is controlled at 11.6-12.0, the ammonium concentration of the reaction system is 3.0-8.0 g / L, and the reaction time is controlled at 10-60 min.

[0022] In one preferred embodiment, during the nucleation stage of S2, a nickel-cobalt-manganese mixed salt solution, an aqueous sodium hydroxide solution, and an aqueous ammonia solution are continuously added to the first reactor in a parallel flow until the pH of the reaction system is adjusted from 11.6-12.0 to 10.0-10.5.

[0023] The ammonium concentration was adjusted from 3.0-8.0 g / L to 5.0-8.0 g / L.

[0024] In one preferred embodiment, in step S1, the concentration of the nickel-cobalt-manganese mixed salt solution is 1.0-2.5 mol / L, the concentration of the sodium hydroxide aqueous solution is 5-12 mol / L, and the concentration of the ammonia aqueous solution is 3-8 mol / L. In another preferred embodiment, in step S1, stirring is performed under temperature control, with the temperature of the first reaction vessel set at 45-60°C and the stirring speed at 100-500 rpm.

[0025] In one preferred embodiment, in step S3, the feeding is stopped, and the slurry in the first and second reactors is aged; the aged slurry is washed and dried, then demagnetized, sieved, and packaged to obtain a nickel-cobalt-manganese ternary precursor material with a diameter range of 0.3-0.9.

[0026] In one preferred embodiment, the nickel-cobalt-manganese ternary precursor material has the structural formula Ni x Co y Mn (1-x-y) (OH)2;

[0027] Among them, 0 <x<1,0<y<1,0<z<1;

[0028] In one preferred embodiment, the D50 of the nickel-cobalt-manganese ternary precursor material is 8-12 μm; the structural formula of the nickel-cobalt-manganese ternary precursor material is Ni x Co y Mn (1-x-y) In (OH)2, 0.7≤x≤0.95, 0≤y≤0.2, and 0≤z≤0.3.

[0029] The present invention also provides an apparatus for preparing ternary precursors with different particle size distributions, which is applied as described above in the method for preparing ternary precursors with different particle size distributions, including a first reactor, a second reactor, pipelines and a circulation system, wherein the pipelines are connected to the first reactor and the second reactor, and the pipelines are connected to the overflow port of the first reactor;

[0030] The first reaction vessel is a seed crystal vessel, which is equipped with a first stirring element and a first discharge port;

[0031] The second reaction vessel is a discharge vessel, and the volume of the second reaction vessel is twice the volume of the first reaction vessel. The second reaction vessel is equipped with a second agitator and a second discharge port.

[0032] The circulation system is also connected to the first reactor and the second reactor.

[0033] In one preferred embodiment, the first reactor is provided with inlet pipes for a nickel-cobalt-manganese mixed salt solution, an aqueous sodium hydroxide solution, and an aqueous ammonia solution;

[0034] Both the first and second reactors are used for the reaction in an inert gas atmosphere.

[0035] Based on the above technical solution, compared with the prior art, the present invention has the following advantages and beneficial effects:

[0036] (1) The method for preparing ternary precursors with different particle size distributions provided by the present invention involves a co-precipitation reaction in a first reactor and a second reactor. The first reactor is used for reaction crystallization, while the second reactor is used for mother liquor removal, allowing the slurry to circulate and the particle size to increase synchronously. This preparation method, through process optimization, simplifies operation, improves production efficiency, and enables more precise control of particle size distribution.

[0037] (2) The apparatus for preparing ternary precursors with different particle size distributions provided by the present invention uses a first reactor as a seed reactor and a second reactor as a clearing reactor connected in series. The circulation system circulates the mechanical energy of the slurry. By controlling the slurry volume or circulation mode of the second reactor, ternary precursors with different particle size distributions can be prepared. Attached Figure Description

[0038] Figure 1 This is a flowchart of the preparation method of ternary precursors with different particle size distributions according to the present invention.

[0039] Figure 2 This is a schematic diagram of the apparatus for preparing ternary precursors with different particle size distributions according to the present invention.

[0040] Figure 3 This is an electron microscope image of the ternary precursor prepared according to the present invention. Detailed Implementation

[0041] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings and specific embodiments. Preferred embodiments are provided. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the present invention.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0043] Example 1

[0044] Figure 1 This is a flowchart of the preparation method of ternary precursors with different particle size distributions in this embodiment, as shown below. Figure 1 As shown, a method for preparing ternary precursors with different particle size distributions includes the following steps:

[0045] S1. Pretreatment stage for coprecipitation reaction;

[0046] S2. Coprecipitation reaction stage;

[0047] S3. Post-treatment stage of coprecipitation reaction.

[0048] Specifically, the S1. coprecipitation reaction pretreatment stage includes the following steps:

[0049] Prepare a mixed salt solution of nickel, cobalt, and manganese, an aqueous solution of sodium hydroxide, and an aqueous solution of ammonia, respectively.

[0050] The concentration of the nickel-cobalt-manganese mixed salt solution is 1.0-2.5 mol / L, the concentration of the sodium hydroxide aqueous solution is 5-12 mol / L, and the concentration of the ammonia aqueous solution is 3-8 mol / L.

[0051] The mixed nickel-cobalt-manganese salt solution, aqueous sodium hydroxide solution and aqueous ammonia solution are added into the first reactor (seed crystal kettle) to form and prepare the coprecipitation reaction base solution, so that the pH value and ammonium radical concentration of the reaction system meet the requirements of the crystal nucleus preparation stage; during this period, the temperature of the first reactor is set to 45-60°C, the stirring speed is 100-500rpm, and stirring is performed under this temperature control environment, so that the volume percentage of oxygen content in the reaction system is lower than 3%.

[0052] In S2. the coprecipitation reaction stage, the following steps are specifically included:

[0053] (1) Crystal nucleus preparation stage: The mixed nickel-cobalt-manganese salt solution, aqueous sodium hydroxide solution and aqueous ammonia solution are added concurrently into the first reactor (seed crystal kettle), the pH of the reaction system is controlled at 11.6-12.0, the ammonium radical concentration of the reaction system is 3.0-8.0g / L, and the control time is 10-60min.

[0054] (2) Crystal nucleus growth stage: The mixed nickel-cobalt-manganese salt solution, aqueous sodium hydroxide solution and aqueous ammonia solution are continuously added concurrently into the first reactor, the pH of the reaction system is controlled at 10.0-10.5, and the ammonium radical concentration of the reaction system is 5.0-8.0g / L; after the liquid level of the first reactor reaches the overflow port, the slurry flows into the second reactor, and the slurry circulation between the first reactor and the second reactor is started; when the liquid level of the second reactor submerges the filter rod, the mother liquor is started to be discharged until the particle size D50 of the ternary precursor grows to 5-15μm, preferably 8-12μm.

[0055] In S3. the post-treatment stage of the coprecipitation reaction, the following steps are specifically included:

[0056] Stop feeding, and age the slurry in the first reactor and the second reactor;

[0057] Wash and dry the aged slurry;

[0058] The dried material is subjected to demagnetization, sieving and packaging, so as to obtain a nickel-cobalt-manganese ternary precursor material with a span range of 0.3-0.9.

[0059] The structural formula of the prepared nickel-cobalt-manganese ternary precursor material is Ni x Co y Mn (1-x-y) (OH)₂;

[0060] Wherein, 0<x<1, 0<y<1, 0<z<1; preferably, 0.7≤x≤0.95, 0≤y≤0.2, 0≤z≤0.3.

[0061] Preferably, the D50 of the nickel-cobalt-manganese ternary precursor material is 8-12μm.

[0062] Figure 2 This is a schematic diagram of the apparatus for preparing ternary precursors with different particle size distributions in this embodiment, as shown below. Figure 2 As shown, the preparation method of ternary precursors with different particle size distributions in this embodiment is carried out in the preparation apparatus 100. The preparation apparatus 100 adopts a dual-reactor series structure, which includes a first reactor 1, a second reactor 2, a pipeline 3, and a circulation system 4. The pipeline 3 connects the first reactor 1 and the second reactor 2. The pipeline 3 is arranged at an angle, and the connection port of the pipeline 3 in the first reactor 1 is higher than the connection port in the second reactor 2. Moreover, the pipeline 3 is connected to the overflow port 10 of the first reactor 1. When there is too much slurry in the first reactor 1, it will flow into the second reactor 2 through the pipeline 3.

[0063] In this embodiment, the first reaction vessel 1 is a seed crystal vessel. The first reaction vessel 1 is provided with a first stirring element 11 and a first discharge port 12. Moreover, the first reaction vessel 1 is also provided with a nickel-cobalt-manganese mixed salt solution inlet pipe 51, a sodium hydroxide aqueous solution inlet pipe 52 and an ammonia aqueous solution inlet pipe 53, which are respectively used to flow into the nickel-cobalt-manganese mixed salt solution, the sodium hydroxide aqueous solution and the ammonia aqueous solution.

[0064] The second reactor 2 is a discharge vessel, and its volume is twice that of the first reactor 1. The second reactor 2 is equipped with a second agitator 21 and a second discharge port 22. The second reactor also has a filter rod assembly 23, which includes a lower filter rod 231 and an upper filter rod 232. The circulation system 4 is also connected to both the first reactor 1 and the second reactor 2.

[0065] It should be noted that both the first reactor 1 and the second reactor 2 are carried out in an inert gas atmosphere. Therefore, inert gas inlet pipes 54 are respectively provided in the first reactor 1 and the second reactor 2, allowing the introduction of inert gases, such as nitrogen. The ternary precursor preparation apparatus provided in this embodiment uses a first reactor as a seed reactor and a second reactor as a clearing reactor connected in series. The circulation system circulates the mechanical energy of the slurry. By controlling the slurry volume or circulation mode in the second reactor, ternary precursors with different particle size distributions can be prepared, making it suitable for large-scale production.

[0066] This preparation method falls between batch and semi-continuous methods, allowing for more precise control of the precursor particle size distribution. The particle size distribution can be controlled within the ranges of 0.3-0.5, 0.5-0.7, and 0.7-0.9 mm, respectively. It is simple to operate and has high production efficiency. The preparation method provided in this embodiment is also applicable to the preparation of binary or multi-component precursors and particles of varying sizes.

[0067] Ternary precursors with different particle size distributions were prepared in the above-described preparation apparatus. The preparation method provided in this embodiment involves a co-precipitation reaction in a first reactor and a second reactor. The first reactor performs reaction crystallization, while the second reactor performs mother liquor removal, allowing the slurry to circulate and the particle size to increase synchronously. This preparation method, through process optimization, simplifies operation, improves production efficiency, and enables more precise control of particle size distribution.

[0068] Example 2

[0069] A ternary precursor with different particle size distribution is prepared by the following method, specifically including the following steps:

[0070] S1. Preparations before the coprecipitation reaction

[0071] Prepare a nickel-cobalt-manganese mixed salt solution with a nickel-cobalt-manganese ratio of 94:3:3 and a total concentration of 1.8-2.2 mol / L; prepare a sodium hydroxide aqueous solution with a concentration of 4.0-6.0 mol / L; and prepare an ammonia aqueous solution with a concentration of 3.0-5.0 mol / L.

[0072] Prepare the coprecipitation reaction base solution by adding pure water, an appropriate amount of nickel-cobalt-manganese mixed salt solution, an appropriate amount of sodium hydroxide aqueous solution, and an appropriate amount of ammonia aqueous solution to the first reaction vessel, which serves as the seed crystal vessel, so that the pH value and ammonium concentration of the reaction system meet the requirements of the crystal nucleus preparation stage. During this process, the temperature of the first reaction vessel is set at 50°C and the stirring speed is set at 500 rpm. Stirring is carried out under this temperature-controlled environment to ensure that the oxygen content of the reaction system is less than 3% by volume.

[0073] S2. Coprecipitation reaction stage.

[0074] (1) Crystal nucleus preparation stage: Nickel-cobalt-manganese mixed salt solution, sodium hydroxide aqueous solution and ammonia aqueous solution are added to the first reaction vessel in parallel flow. The pH of the reaction system is controlled at 11.6-11.8, the ammonium concentration of the reaction system is 3.0-5.0 g / L, and the reaction time is controlled at 15 min.

[0075] (2) Crystal growth stage: Continue to add nickel-cobalt-manganese mixed salt solution, sodium hydroxide aqueous solution and ammonia aqueous solution to the first reactor in parallel flow, control the pH of the reaction system to 10.0-10.2, and the ammonium concentration of the reaction system to 6.0-8.0 g / L; after the liquid level in the first reactor reaches the overflow port, the slurry flows into the second reactor. When the liquid level in the second reactor exceeds the lower filter rod 231, start to remove the mother liquor and start the slurry circulation between the first reactor and the second reactor; control the liquid level in the second reactor at the lower filter rod 231 until the particle size D50 of the ternary precursor grows to 12.3 μm.

[0076] S3. Post-treatment stage of coprecipitation reaction.

[0077] Stop feeding and age the slurry in the first and second reactors;

[0078] The aged slurry is washed and dried;

[0079] The dried material is demagnetized, sieved, and packaged to obtain a nickel-cobalt-manganese ternary precursor material with a diameter of 0.583.

[0080] Electron microscopy images of the prepared nickel-cobalt-manganese ternary precursor materials are shown below. Figure 3 As shown.

[0081] Example 3

[0082] This embodiment modifies the rinsing control conditions in the coprecipitation reaction stage, specifically as follows:

[0083] S2. Coprecipitation Reaction Stage - Crystal Nucleus Growth Stage: Continue to add the nickel-cobalt-manganese mixed salt solution, sodium hydroxide aqueous solution, and ammonia aqueous solution in parallel to the first reactor, controlling the pH of the reaction system to be 10.0-10.2 and the ammonium concentration of the reaction system to be 6.0-8.0 g / L; after the liquid level in the first reactor reaches the overflow port, the slurry flows into the second reactor, and the slurry circulation between the first and second reactors begins; when the liquid level in the second reactor exceeds the lower filter rod 231, start to remove the mother liquor; control the liquid level in the second reactor at the lower filter rod 231 until the particle size D50 of the ternary precursor grows to 12.3 μm.

[0084] The remaining operation steps are the same as in Example 2, which prepared a nickel-cobalt-manganese ternary precursor material with a diameter of 0.370.

[0085] Example 4

[0086] This embodiment modifies the rinsing control conditions in the coprecipitation reaction stage, specifically as follows:

[0087] S2. Coprecipitation reaction stage - crystal nucleus growth stage: Continue to add nickel-cobalt-manganese mixed salt solution, sodium hydroxide aqueous solution and ammonia aqueous solution in parallel to the first reactor, control the pH of the reaction system to be 10.0-10.2, and the ammonium concentration of the reaction system to be 6.0-8.0 g / L; after the liquid level in the first reactor reaches the overflow port, the slurry flows into the second reactor. When the liquid level in the second reactor exceeds the upper filter rod 232, start to remove the mother liquor and start the slurry circulation between the first reactor and the second reactor; control the liquid level in the second reactor at the upper filter rod 232 until the particle size D50 of the ternary precursor grows to 12.3 μm.

[0088] The remaining operation steps are the same as in Example 2, which prepared a nickel-cobalt-manganese ternary precursor material with a diameter of 0.732.

[0089] Comparative Example 1

[0090] In the preparation method of the ternary precursor in Comparative Example 1, the coprecipitation reaction stage was controlled by a pure intermittent extraction of mother liquor.

[0091] In the coprecipitation reaction stage - crystal nucleus growth stage: a nickel-cobalt-manganese mixed salt solution, sodium hydroxide aqueous solution and ammonia aqueous solution are added to the first reactor in parallel flow, and the pH of the reaction system is controlled at 10.0-10.2, and the ammonium concentration of the reaction system is 6.0-8.0 g / L. After the liquid level in the first reactor reaches the overflow port, feeding and stirring are stopped, and after standing, the supernatant is extracted, stirring and feeding are started again, and the above operation is repeated until the particle size D50 of the ternary precursor grows to 12.3 μm.

[0092] This comparative example did not use a second reactor connected in series with the first reactor. The remaining operation process was the same as in Example 2. The example prepared a nickel-cobalt-manganese ternary precursor material with a diameter of 0.356.

[0093] Comparative Example 2

[0094] The preparation method of the ternary precursor in Comparative Example 2 adopts a semi-continuous method to control the coprecipitation reaction stage.

[0095] In the co-precipitation reaction stage - crystal nucleus growth stage: a nickel-cobalt-manganese mixed salt solution, sodium hydroxide aqueous solution and ammonia aqueous solution are added to the first reactor in parallel flow, and the pH of the reaction system is controlled at 10.0-10.2, and the ammonium concentration of the reaction system is 6.0-8.0 g / L; after the liquid level in the first reactor reaches the overflow port, the slurry is directly overflowed into the unqualified tank for recycling until the particle size D50 of the ternary precursor grows to 12.3 μm.

[0096] This comparative example did not use a second reactor connected in series with the first reactor. The remaining operation process was the same as in Example 2. The example prepared a nickel-cobalt-manganese ternary precursor material with a diameter of 0.532.

[0097] The particle size of the ternary precursors prepared in Examples 2-4, Comparative Example 1 and Comparative Example 2 was tested, and the results are shown in Table 1.

[0098] Table 1. Particle size test results of ternary precursors from Examples 2-4 and Comparative Examples 1-2.

[0099] Example 1 9.225 12.310 16.402 0.583 Example 2 10.206 12.300 14.754 0.370 Example 3 7.906 12.295 17,275 0.762 Comparative Example 1 10.443 12.302 14.823 0.356 Comparative Example 2 9.476 12.299 16.019 0.532

[0100] The above description is merely an example and illustration of the present invention, and while the description is specific and detailed, it should not be construed as limiting the scope of the present invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these obvious substitutions all fall within the protection scope of the present invention.

Claims

1. A method for preparing ternary precursors with different particle size distributions, characterized in that, A ternary precursor is prepared using a preparation apparatus, which includes a first reaction vessel, a second reaction vessel, pipelines, and a circulation system. The pipelines connect the first reaction vessel and the second reaction vessel, and are connected to the overflow port of the first reaction vessel. The first reaction vessel is a seed crystal vessel, which is equipped with a first stirring element and a first discharge port; The second reaction vessel is a discharge vessel, and the volume of the second reaction vessel is twice the volume of the first reaction vessel. The second reaction vessel is equipped with a second agitator and a second discharge port. The circulation system is also connected to the first reactor and the second reactor; The first reaction vessel is equipped with inlet pipes for a nickel-cobalt-manganese mixed salt solution, an aqueous sodium hydroxide solution, and an aqueous ammonia solution; Both the first and second reactors are used for the reaction in an inert gas atmosphere; The second reactor is also equipped with a filter rod assembly, which includes a lower filter rod and an upper filter rod. The preparation method of the ternary precursors with different particle size distributions includes the following steps: S1. Pretreatment stage for coprecipitation reaction Prepare a mixed salt solution of nickel, cobalt, and manganese, an aqueous solution of sodium hydroxide, and an aqueous solution of ammonia, respectively. A mixed salt solution of nickel, cobalt, and manganese, an aqueous solution of sodium hydroxide, and an aqueous solution of ammonia were added to the first reaction vessel to form a coprecipitation reaction base liquid. The mixture was stirred under temperature control to ensure that the oxygen content of the reaction system was less than 3% by volume. S2. Coprecipitation reaction stage, including nucleus preparation stage and nucleus growth stage; In the nucleus preparation stage, a mixed salt solution of nickel, cobalt, and manganese, an aqueous solution of sodium hydroxide, and an aqueous solution of ammonia are added to the first reactor in parallel streams. The pH of the reaction system is controlled at 11.6-12.0, the ammonium concentration of the reaction system is 3.0-8.0 g / L, and the reaction time is controlled at 10-60 min. During the nucleus growth stage, a mixed nickel-cobalt-manganese salt solution, an aqueous sodium hydroxide solution, and an aqueous ammonia solution are continuously added to the first reactor in a parallel flow until the pH of the reaction system is adjusted from 11.6-12.0 to 10.0-10.5 and the ammonium concentration is adjusted from 3.0-8.0 g / L to 5.0-8.0 g / L. After the liquid level in the first reactor reaches the overflow port, the slurry flows into the second reactor, and slurry circulation between the first and second reactors begins. When the liquid level in the second reactor exceeds the lower or upper filter rod, the mother liquor is drained until the particle size D50 of the ternary precursor grows to 5-15 μm. S3. Post-treatment stage of coprecipitation reaction The feeding was stopped, and the slurry in the first and second reactors was aged. The aged slurry was washed and dried, then demagnetized, sieved, and packaged to obtain nickel-cobalt-manganese ternary precursor materials with a diameter range of 0.3-0.

9.

2. The method for preparing ternary precursors with different particle size distributions according to claim 1, characterized in that, In S1, the concentration of the nickel-cobalt-manganese mixed salt solution is 1.0-2.5 mol / L, the concentration of the sodium hydroxide aqueous solution is 5-12 mol / L, and the concentration of the ammonia aqueous solution is 3-8 mol / L.

3. The method for preparing ternary precursors with different particle size distributions according to claim 1, characterized in that, In step S1, stirring is performed under temperature control, with the temperature of the first reaction vessel set at 45-60℃ and the stirring speed at 100-500 rpm.

4. The method for preparing ternary precursors with different particle size distributions according to claim 1, characterized in that, The structural formula of the nickel-cobalt-manganese ternary precursor material is Ni x Co y Mn (1-x-y) (OH)2; Among them, 0 <x<1,0<y<1,0<z<1。 5. The method for preparing ternary precursors with different particle size distributions according to claim 4, characterized in that, The D50 of the nickel-cobalt-manganese ternary precursor material is 8-12 μm; The structural formula of the nickel-cobalt-manganese ternary precursor material is Ni x Co y Mn (1-x-y) In (OH)2, 0.7≤x≤0.95, 0≤y≤0.2, and 0≤z≤0.3.

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