KR101919517B1 - Co-precipitation reactor for composing a big concentrat gradient precurs and this method - Google Patents

Abstract

A core solution consisting of a metal aqueous solution and a buffer solution and a shell solution to produce an opposite precursor having a center particle size of at least 18 microns among the concentration gradient type precursors continuously changing the metal composition from the center of the particle through the batch type coprecipitation reactor Two or more reservoirs provided so as to store or input the contents; A main reactor in which a metal aqueous solution is supplied by the operation of a metering pump and the coprecipitation reaction is performed in the reservoir; And an auxiliary reactor connected in series with the main reactor to supply a metal aqueous solution through a circulation pump to conduct a coprecipitation reaction, and a method for synthesizing the batch type coprecipitation reactor for synthesizing a concentration gradient type precursor precursor.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a batch type coprecipitation reaction apparatus for synthesizing a concentration gradient type precursor precursor,

A batch type coprecipitation reaction apparatus, a method of producing a concentration gradient type precursor through the same, and a cathode material manufactured using the same.

As an implementation method for the development direction of a lithium secondary battery called a high energy density, an upward control of the rolling density is being performed. As a concrete method thereof, a bimodal method of a large-sized anode material is used.

This minimizes intergranular porosity and increases the density per unit volume. In order to realize an effective rolling density, the particle size of the major particle is required to be 18 microns or more, and more effective particle size is required to be 20 microns or more.

At present, the major factor determining the particle size of the anode material is determined by the particle size of the precursor, and the precursor of the high-capacity NCM-based cathode material is generally manufactured by the co-impregnation method. The co-invasion method is a method of synthesizing spherical precursors due to the complex factors of chemical precipitation and mechanical mixing between the materials. Due to the effect of precursor properties on particle growth in the co-impregnation process, generally 8 to 15 micron range of products are common, and particle size is not well produced.

Particularly, in the case of conventional concentration gradient type precursors, the composition and purity of at least two or more metal aqueous solutions having different compositions are determined at design time, and the products are produced through dilution / coprecipitation at different time intervals. In order to produce this changing concentration-gradient precursor, the raw materials and reactants must be present in a confined state in the closed space until the end of the reaction. For this purpose, a batch type coprecipitation reaction system is used, and a batch type coprecipitation reaction and a concentration gradient type precursor It has been difficult to realize a particle size of 18 microns or more, preferably 20 microns or more in a situation where the total reaction time is fixed to a fixed value.

A batch type coprecipitation reaction apparatus for producing a concentration gradient type precursor precursor in which a concentration gradient type precursor continuously changing a metal composition from the center of a particle through a batch type coprecipitation reactor is produced to have an opposite precursor having a center particle size of at least 18 microns And provides a synthesis method thereof.

The batch type coprecipitation reactor for synthesizing the concentration gradient type precursor precursor includes at least two reservoirs which are installed to store or inject a core solution comprising a metal aqueous solution and a buffer solution and a shell solution; A main reactor in which a metal aqueous solution is supplied by the operation of a metering pump and the coprecipitation reaction is performed in the reservoir; And an auxiliary reactor connected in series with the main reactor to supply the aqueous metal solution through the circulation pump to perform the coprecipitation reaction.

The reservoir includes a buffer solution reservoir in which the buffer solution is stored / stored, a metal aqueous solution reservoir in which the core solution or the shell solution is accommodated / stored, and a composition control solution reservoir in which the composition control solution is accommodated / stored.

The main reactor further includes a pH control agent storage tank installed at one side of the main reactor and supplied with a control agent by operation of a metering pump.

The main reactor further includes a growth control material storage tank installed at one side of the main reactor and supplied with a growth control material by the operation of a metering pump.

The gradient gradient type precursors can be synthesized by coupling two or more batch-type coprecipitation reactors in series and circulating and homogenizing the solution to be added. In the course of addition and addition of the core solution and the shell solution, The solution is put into a storage tank in which the core solution is stored, and then charged into the batch type coprecipitation reactor in accordance with the designed concentration gradient.

The metal aqueous solution may be introduced into the batch type coprecipitation reactor using three or more reservoirs capable of storing / injecting the core solution, the buffer solution and the shell solution at the front end of the batch type coprecipitation reactor.

The buffer solution may be prepared / reacted in two or more reservoirs capable of storing / injecting the core solution and the shell solution at the front end of the batch type coprecipitation reactor, and then the shell solution may be prepared / introduced into the batch type coprecipitation reactor.

The core solution is introduced into the batch type coprecipitation reactor at the start of the reaction of the metal aqueous solution, and the buffer solution is transferred / mixed in the same amount as the flow rate of the core solution to the core solution reservoir, Can be controlled so as not to change.

The buffer solution is further added or decreased according to the growth rate / tendency when the core solution and the buffer solution are mixed to transfer / mix the shell solution to the core solution reservoir at the target middle size, thereby obtaining an additional concentration gradient and a target composition The grain size can be completed.

According to the present apparatus, the defective rate due to poor particle size of the final product is reduced by controlling and expanding the variable reaction time within a certain range according to the use of the buffer solution which does not affect the final target composition in the synthesis of the concentration gradient type precursor precursor Concentration gradient type precursors can be synthesized in a concentration gradient of more than 18 microns, preferably 20 microns or more, and the synthesis, growth rate and variable reaction time due to the influence of the composition of the core- It has the advantage of excellent productivity compared to the existing core-shell of the same size due to enlarged operation.

In addition, the method of operating the core-buffer-shell metal aqueous solution exhibits different concentration gradient slopes before and after the introduction of the aqueous solution of the shell metal depending on the use of the three kinds of metal aqueous solutions and the input conditions, - Despite the large amount of shell concentration gradient products, it has excellent physicochemical and electrochemical properties. It also has an advantage of its own rolling density increase due to substitution hardening and also excellent in energy density per volume due to bimodalization.

1 is a view schematically showing a batch type coprecipitation reaction apparatus for synthesizing a concentration gradient type precursor precursor according to the present embodiment.
2 is a graph showing the growth of the precursor particles according to the present embodiment and the comparative example.
3 is a graph showing the compositional change (design value) according to the reaction time according to this embodiment and the comparative example.
FIG. 4 is a graph showing a composition analysis result (EPMA) of a cross section of a precursor according to the present embodiment and a comparative example.
5 is a diagram showing a precursor shape (SEM) according to the present embodiment and a comparative example.
Fig. 6 is a view showing the shape and cross section (FIB) of a cathode material according to this embodiment and a comparative example.
7 is a graph showing the rolling density (pellet density) of the cathode material according to the present embodiment and the comparative example.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms as used herein include plural forms as long as the phrases do not expressly express the opposite meaning thereto. Means that a particular feature, region, integer, step, operation, element and / or component is specified, and that other specific features, regions, integers, steps, operations, elements, components, and / And the like.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Accordingly, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

1 is a view schematically showing a batch type coprecipitation reaction apparatus for synthesizing a concentration gradient type precursor precursor according to the present embodiment.

As shown in FIG. 1, in the process of producing a concentration gradient type precursor that continuously changes the metal composition from the core to the shell of the particle, the precursor has a center particle size of 18 microns or more Discloses an efficient batch-type coprecipitation reactor and method for realizing a target particle size of an alloperator of 20 microns or more.

In the present embodiment, the batch type coprecipitation reaction apparatus for concentration gradient type opposite precursor synthesis comprises two or more reservoirs 10 installed to store or inject a core solution made of an aqueous metal solution, a buffer solution and a shell solution; A main reactor (30) for supplying a metal aqueous solution by the operation of the metering pump (20) in the reservoir (10) and conducting the coprecipitation reaction; And an auxiliary reactor (50) connected in series with the main reactor (30) to supply a metal aqueous solution through the circulation pump (40) to conduct a coprecipitation reaction.

In addition, the reservoir 10 includes a buffer solution reservoir 11 in which a buffer solution is stored / stored, a metal aqueous solution reservoir 12 in which a core solution or a shell solution is accommodated / stored, and a composition And a control solution reservoir 13.

The main reactor 30 further includes a pH control agent storage tank 61 installed at one side of the main reactor 30 and supplied with an adjusting agent by the operation of the metering pump 20, And a growth control material storage tank 62 supplied with the growth control material by the operation of the metering pump 20.

In the method of synthesizing a concentration gradient type precursor precursor, two or more batch-type coprecipitation reactors are connected in series, so that even when the added solution is further added or added to the core solution and the shell solution in the process of circulating and homogenizing the solution, Into the storage tank where the core solution is stored, and then charging the buffer solution into the batch type coprecipitation reactor in accordance with the designed concentration gradient.

In this case, the metal aqueous solution can be introduced into the batch type coprecipitation reactor using three or more reservoirs capable of storing / injecting the core solution, the buffer solution and the shell solution at the front end of the batch type coprecipitation reactor, The buffer solution may be prepared / reacted in two or more reservoirs capable of storing / injecting the core solution and the shell solution, and then the shell solution may be prepared / injected into the batch type coprecipitation reactor.

Also, at the start of the reaction of the metal aqueous solution, the core solution is charged into the batch type coprecipitation reactor, and then the buffer solution is transferred / mixed in the same amount as the input flow rate of the core solution to sequentially change the composition, So that there is no change in the volume.

In addition, the buffer solution may be further added or decreased according to the growth rate / tendency when the core solution and the buffer solution are mixed to transfer / mix the shell solution to the core solution reservoir at the target middle size, Composition and particle size can be completed.

Therefore, the cathode material using the concentration gradient type precursor synthesis method can be produced by preparing a bulk precursor having a core particle size of at least 18 microns or 20 microns or more through a batch type coprecipitation reactor and firing.

That is, as a method for synthesizing a concentration gradient homologous precursor having a concentration of 18 microns or more, a total reaction time of the conventional core-shell application is measured using three metal aqueous solutions of a core-buffer-shell It is possible to increase the final particle size.

The composition of the buffer solution in the metallic aqueous solution is the final target composition, and the final composition is constant irrespective of whether the buffer solution is added or not.

In addition, when the core-shell metal aqueous solution is applied to the core-buffer-shell application, the buffer solution for the core solution is sequentially mixed until the shell metal aqueous solution is injected, thereby causing particle generation, growth and concentration gradient in the reactor. By confirming the growth tendency with respect to the target particle size and varying the injection time of the buffer solution, it is possible to determine the injection time of the shell solution and ensure stable particle size reproducibility.

The composition of each of the core-buffer-shells has a composition and growth rate that is comparable to that of core ≥ buffer ≥ shell. This indicates that the growth rate from the initial stage to the mid-stage depending on the application of the core- And it is possible to shorten the reaction time to the same particle size as compared with the existing core-shell composite.

The initial reaction, in which the reaction conditions are not stabilized, is a part where there is room to proceed in an undesired direction due to the unstable reaction condition. The initial volume for smooth fluid flow is small The consumption of raw materials for securing the initial conditions can be reduced, and in particular, in the production of the precursor of the concentration gradient method, there is room for controlling the particle size and composition for the reaction time in the initial stabilization portion of the reaction condition.

The method of utilizing three or more metal aqueous solutions of the core-buffer-shell in the concentration gradient type precursor precursor synthesis is not limited to the variable reaction time control and expansion within a certain range according to the buffer utilization which does not affect the final target composition It is possible to synthesize a concentration gradient type precursor precursor having a concentration gradient of 18 microns or more, preferably 20 microns or more, and a synthesis due to the influence of the composition of the core-buffer metal in the concentration gradient type precursor , And an improved reaction rate for the same particle size as the core-shell due to the improvement of the growth rate.

The method of operating the core-buffer-shell metal aqueous solution is excellent in productivity compared to the conventional particle size standard due to the influences of the composition of each raw material and the variable reaction time enlargement operation, and the occurrence rate of defects such as particle size, Synthesis of an opposing precursor is possible.

In this embodiment, for a system in which two or more batch-type coprecipitation reactors and two or more batch-type coprecipitation reactors are connected in series to circulate / homogenize, a buffer solution having no interference in the entire composition, After the solution is added, it is injected in accordance with the designed concentration gradient.

At this time, the buffer solution has the composition of the final product, and it is premised that the buffer solution is added and decreased to the target particle size according to the growth rate of the particles regardless of the designed reaction time.

That is, three or more storage tanks 10 capable of storing / inputting a core, a buffer, and a shell metal aqueous solution may be used in front of the main reactor 30 or two or more storage tanks 10 capable of storing / The present invention provides a structure and a method for manufacturing and introducing a buffered metal aqueous solution and a shell solution after the reaction.

Accordingly, the buffer injection time can be arbitrarily adjusted until the target particle size is reached before the shell solution is introduced, and the target particle size and composition can be secured at the time of completion.

More than two, preferably three or more, reservoirs 10 capable of storing / injecting a core, a buffer, and a shell metal aqueous solution are installed at the front end of the main reactor 30, The buffer metal aqueous solution is transferred / mixed in the same amount as the core input flow rate to the post-core solution reservoir, and the composition is sequentially changed, so that the volume of the available core solution is controlled so as not to change.

At this time, the buffer metal aqueous solution is added / decreased according to the growth rate / trend, and when the desired middle particle size is reached, the shell metal aqueous solution is transferred / mixed to the core solution storage tank to complete additional concentration gradient, target composition and particle size.

The major relationships that apply to these experiments are as follows.

[Key Relationship]

Molar%: (Core + Shell) = Buffer

- Target composition: Ni _x Co _y Mn _z

Core: Ni _{x + a} Co _{y - b} Mn _{z - c}

Buffer: Ni _x Co _y Mn _z

Shell: Ni _{x- a} Co _{y + b} Mn _{z + c}

Metal aqueous solution concentration relation, M: Core ≤ Buffer ≤ Shell

Metal aqueous solution storage tank Flow rate relation: Core ≤ Buffer ≥ Shell (when three volumes of solution are equal)

- Core flowrate: (Core volume + Shell volume) / Total reaction time

- Shell flowrate: ((Shell volume / core volume) * Core flowrate) / 2

(Correlation of flow rate depends on design volume of each reservoir)

2 is a graph showing the growth of the precursor particles according to the present embodiment and the comparative example.

3 is a graph showing the compositional change (design value) according to the reaction time according to this embodiment and the comparative example.

FIG. 4 is a graph showing a composition analysis result (EPMA) of a cross section of a precursor according to the present embodiment and a comparative example.

5 is a diagram showing a precursor shape (SEM) according to the present embodiment and a comparative example.

Fig. 6 is a view showing the shape and cross section (FIB) of a cathode material according to this embodiment and a comparative example.

7 is a graph showing the rolling density (pellet density) of the cathode material according to the present embodiment and the comparative example.

2 to 7, the present invention will be described with reference to specific examples and comparative examples.

Examples. One

In order to synthesize a concentration gradient type precursor with a composition of Ni 80% or more based on the operating volume of 100 L reactor, a metal aqueous solution of a core portion of Ni 90% or more, a shell portion of less than 60% Ni and a buffer portion of Ni 80% And the solution is introduced into the reactor from the storage tank by using a hose type metering pump. The order of introduction of the aqueous solution into the reactor from each storage tank is as follows. Into the core reservoir. At this time, the flow rate of the two solutions is set to be the same so that the total volume of the core reservoir before the buffer solution is injected is not affected.

Upon reaching the middle particle size for achieving the target particle size during the synthesis, the buffer aqueous solution which has been introduced into the core portion storage tank is converted into the aqueous solution of the shell portion, and the target composition is reached upon completion of the reaction.

Examples. 2

From Example 1, except that a core portion of Ni of 70% or more, a shell portion of Ni of 50% or less and a buffer portion of Ni target composition of 60% were applied to synthesize a concentration gradient type precursor of Ni content of 60% And the precursor is synthesized.

Comparative Example. One

In order to synthesize a concentration graded precursor with a composition of Ni of 80% or more based on the operating volume of 100 L reactor, Ni 90% or more core portion and Ni 60% or less shell portion were dissolved in each storage tank, / RTI > is introduced into the reactor / synthesis.

Comparative Example. 1-1

In order to synthesize a bulk form precursor having a composition of Ni 80% or more with respect to an operating volume of 100 L reactor 1, the target composition is dissolved in a storage tank, and then a hose type metering pump is used to enter the reactor.

Comparative Example. 2

From Example 2, a precursor is synthesized through the process of Comparative Example 1 by applying a core portion of Ni of 80% or less and a shell portion of Ni of 50% or less in order to synthesize a concentration gradient type precursory precursor having a Ni content of 60%.

In this embodiment, the cathode material (cathode active material particle) produced through the above experiment is as follows.

In each of the examples and comparative examples, a metal mixed solution having the same composition as shown in Table 1 below was fed in the same manner as in the metal aqueous solution storage tank, the buffer solution storage tank and the composition control solution storage tank, and a precursor for lithium secondary batteries was prepared Respectively.

As described in the case of the embodiment, the order of introduction into the reactor is such that the aqueous metal solution is fed into the reactor and the buffer solution is fed into the metal aqueous solution storage tank at the same flow rate so that the volume of the metal aqueous solution storage tank is not affected. During the synthesis, the buffer solution, which had been loaded into the metal aqueous solution reservoir when the desired middle particle size was reached, was converted to the composition control solution so that it was in accordance with the target composition at the end of the reaction.

In the comparative example, a concentration gradient type precursor was prepared by supplying only the aqueous metal solution and the composition control solution as in the prior art.

Item Composition, mol% The metal aqueous solution (A) The buffer solution (B) The composition control solution (C) The total composition (A + B + C) Ni Co Mn Ni Co Mn Ni Co Mn Ni Co Mn Example 1 95 5 - 83 9 8 71 13 16 83 9 8 Example 2 75 12 13 60 20 20 45 28 27 60 20 20 Comparative Example 1 95 5 - - - - 71 13 16 83 9 8 Comparative Example 1-1 83 9 8 - - - - - - 83 9 8 Comparative Example 2 75 12 13 - - - 45 28 27 60 20 20

Synthesis analysis of the precursors and cathode materials for lithium secondary batteries prepared in Examples and Comparative Examples was carried out and the results were compared. As shown in FIG. 2 to FIG. 7, in the case of the examples, the growth width at the same reaction time is larger than that of the comparative example, and it is confirmed that a precursor with a buffer solution of 20.0 μm or more can be produced by further utilizing the buffer solution.

Table 2 below shows the results of measuring the reaction time, final particle size, filling density and yield of the lithium secondary battery precursors prepared in Examples and Comparative Examples.

Item Total reaction time, hr Target particle size (D50), 탆 Closed particle size (D50), 탆 Filling density, g / cc Example 1 36 ≥ 18.0 20.9 2.38 Example 2 43 ≥ 18.0 19.7 2.33 Comparative Example 1 30 ≥ 18.0 17.8 2.31 Comparative Example 1-1 55 ≥ 18.0 16.9 2.21 Comparative Example 2 30 ≥ 18.0 16.4 2.27

As shown in [Table 2] and FIG. 2, in the examples, the buffer solution which does not affect the target composition shows a faster growth rate than the reaction time, and the variable reaction time control to the desired intermediate particle size In contrast, in the case of the comparative example, as the composition control material is diluted within a fixed limited reaction time, the growth width of the precursor converges to the target particle size.

It can be confirmed that the method of the embodiment is capable of reproducible production in the case of a larger diameter of 18.0 μm or larger.

The particle size of the precursor prepared in the above Examples and Comparative Examples was measured according to the reaction time, and Fig. 2 shows the results.

As shown in FIG. 2, according to the present invention, as the metal aqueous solution and the buffer solution were diluted during the preparation, the reaction proceeded in an aqueous solution state of at least Ni 83% to exhibit a higher growth rate, The reaction time can be variably controlled. Accordingly, it can be confirmed that the method of the embodiment is capable of reproducible production in the concentration graded bulk polymerization of 18.0 μm or more.

The physicochemical and electrochemical properties of the cathode materials for lithium secondary batteries prepared in Examples and Comparative Examples were evaluated, and the results were compared in Table 3 and FIG. 6 and FIG. As shown in each of the examples and comparative examples, it can be confirmed that the performance is equal to or better than that of the comparative example in spite of the large particle size difference.

[Table 3] and FIGS. 6 and 7 show the physicochemical and electrochemical properties of the cathode material for a lithium secondary battery manufactured in Examples and Comparative Examples.

[Assessment Methods]

Electrochemical Characterization

 Evaluation Equipment: Toscat-3100

 Evaluation Condition: Charging - CC / CV 4.25V, 1 / 20C Cut-off

           Discharge - CC 3.0V Cut-off

Rolling density evaluation

Evaluation Equipment: CARVER 4350

Item 0.1 C discharge capacity, mAh / g 1 ^st reversible efficiency,
% 2.0 / 0.1C Efficiency,
% Filling density,
g / cc Rolling density @ 2.5 tonnes, g / cc Example 1 204.8 90.4 88.4 2.63 3.53 Example 2 175.6 90.2 88.9 2.50 3.46 Comparative Example 1 202.4 91.7 88.4 2.44 3.41 Comparative Example 1-1 199.7 89.7 87.6 2.38 3.40 Comparative Example 2 176.2 90.3 88.5 2.38 3.38

The synthesis through this example is superior to the comparative example in the same reaction time zone, and the performance of the anode material through the anode material is similar or equal to or better than that of the anode material in terms of energy density.

On the other hand, FIG. 2 is a graph showing the growth of precursor particles in Examples and Comparative Examples, and shows the grain growth tendency in Examples and Comparative Examples for the synthesis of concentration gradient type precursors (D50: ≥18.0 μm) in a batch type coprecipitation reactor.

(D50: > = 18.0 mu m) within a short reaction time as compared with the comparative example, the dilution of the shell solution and the difference (Ni, Mn) The growth rate is converged by the growth rate slowing due to the increase of the reaction time.

In the case of the example, it was confirmed that the growth rate was fast according to the concentration difference (Ni, Mn) in the same reaction time zone as compared with the comparative example.

As shown in FIG. 3, in the preparation of the concentration gradient type precursor of the example, the total reaction time can be variably controlled through the injection of the buffer solution until the desired middle particle size is reached before the composition control solution is introduced, Type precursor, the total reaction time is fixed according to the total and application composition applied at the time of design, and it is impossible to control and change the particle size between the reaction progresses.

Further, as shown in Fig. 4, in the production of the concentration gradient type precursors of the examples and the comparative examples, the composition distribution is different by the difference in the method of diluting the composition from the central part. The core-buffer-shell type concentration gradient method of the embodiment achieves the target composition after reaching a certain reaction time, while the core-shell type concentration gradient method of the comparative example changes linearly to achieve the target composition, It can be controlled variably. It shows the change of shape that converges above the target composition due to the process characteristics. When the shell metal aqueous solution is applied, it exhibits two types of concentration change which shows a linear gradient of the concentration, and the composition is diluted during the heat treatment in the final cathode active material And the concentration gradient characteristic is further developed.

As shown in Figs. 5 and 6, the crystal form of the cathode material produced by using the precursors and concentration gradient type precursors of Examples and Comparative Examples is shown. The same tendency is shown in the cross-sectional crystal orientation of the examples and comparative examples utilizing the concentration gradient type precursor.

As shown in FIG. 7, the rolling density analysis of the cathode material produced by using the concentration gradient type precursors of Examples and Comparative Examples shows that the rolling density increases (energy density increases) in proportion to the central grain size.

While the illustrative embodiments of the present invention have been shown and described, various modifications and alternative embodiments may be made by those skilled in the art. Such variations and other embodiments will be considered and included in the appended claims, all without departing from the true spirit and scope of the invention.

10: storage tank 11: buffer solution storage tank
12: metal aqueous solution storage tank 13: composition control solution storage tank
20: metering pump 30: main reactor
40: circulation pump 50: auxiliary reactor
61: pH control control agent storage tank 62: Growth control substance storage tank

Claims (9)

Two or more reservoirs provided so as to store or input a core solution made of a metal aqueous solution, a buffer solution and a shell solution;
A main reactor in which a metal aqueous solution is supplied by the operation of a metering pump and the coprecipitation reaction is performed in the reservoir; And
And an auxiliary reactor connected in series with the main reactor to supply the aqueous metal solution through the circulation pump to perform the coprecipitation reaction,
Wherein the buffer solution is a metal aqueous solution for a target particle size of the precursor. The method according to claim 1,
The reservoir includes a metal-aqueous solution reservoir for containing / storing a buffer solution, a metal-aqueous solution reservoir for containing / storing the core solution, and a composition control solution reservoir for containing / storing the composition- Coprecipitation reaction device. The method according to claim 1,
Wherein the main reactor further comprises a pH control agent storage tank installed at one side of the main reactor and supplied with a control agent by operation of a metering pump. The method according to claim 1,
Wherein the main reactor further comprises a growth control material storage tank provided at one side thereof and supplied with a growth control material by the operation of a metering pump. In the course of circulating and homogenizing a solution to be introduced by connecting two or more batch-type coprecipitation reactors in series, the buffer solution which is free from interference in the entire composition and which is a metal aqueous solution for the target particle size of the precursor, Introducing the solution into a storage tank in which the core solution is stored, and then introducing the solution into the batch type coprecipitation reactor in accordance with the designed concentration gradient. 6. The method of claim 5,
Wherein the metal aqueous solution can be introduced into the batch type coprecipitation reactor using three or more reservoirs capable of storing / injecting the core solution, the buffer solution and the shell solution at the front end of the batch type coprecipitation reactor. delete The method according to claim 6,
The core solution is introduced into the batch type coprecipitation reactor at the start of the reaction of the metal aqueous solution, and the buffer solution is transferred / mixed in the same amount as the flow rate of the core solution to the core solution reservoir, Wherein the concentration gradient-type alligator precursor can be controlled so as not to be changed. 6. The method of claim 5,
The buffer solution is further added or decreased according to the growth rate / tendency when the core solution and the buffer solution are mixed to transfer / mix the shell solution to the core solution reservoir at the target middle size, thereby obtaining an additional concentration gradient and a target composition A method for synthesizing a concentration gradient type precursor precursor capable of completing the particle size.

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