KR20160115578A - Apparatus and method for manufacturing precursor and precursor prepared therefrom - Google Patents

Abstract

The present invention relates to an apparatus for preparing a precursor, which improves the flow of a Taylor-Couette reactor to obtain an anode precursor having high density and small particle sizes. The apparatus for preparing a precursor comprises: a reactor which includes an external cylinder provided with an inlet formed at one side and an outlet formed at the other side and having an internal space, and a rotating barrel disposed in the external cylinder homocentrically therewith and installed to be able to rotate to form a Taylor eddy between the rotating barrel and the external cylinder; a driving motor linked to the rotating barrel to rotate the rotating barrel; a precursor starting material-supplying section for supplying a precursor starting material to the inlet; a chelating agent-supplying section for supplying a chelating agent; and a modifier-supplying section for supplying a pH modifier. In the apparatus, the reactor is formed to have the number of gaps (d/ri) more than 0.05 and less than 0.2.

Description

TECHNICAL FIELD [0001] The present invention relates to a precursor producing apparatus, a precursor producing apparatus, a precursor producing apparatus, a precursor producing apparatus,

Discloses a precursor production apparatus, a production method, and a precursor produced therefrom, which comprises a reactor using a Kuett-Taylor vortex to produce a precursor.

For example, as a method for continuously producing a ternary cathode precursor in a cathode material for a secondary battery, a technique using a Taylor-Kuett reactor as in Patent Documents 1 to 3 is known. The process of preparing a coprecipitate precursor using a Taylor-Quatt reactor has the advantage that a retention time is short and a concentration gradient precursor can be produced as compared with a process using a continuous tank reactor (CSTR).

However, in the case of the prior art in which a concentration gradient precursor is produced using a Taylor-Kuert reactor, there is a limit to give a high concentration gradient and there is a limit to the production of a high-density and low-particle-size precursor as compared with a batch type reactor . In addition, when the low particle size precursor is produced by improving the flow path in the reactor and increasing the flow of the particles by reducing the residence time, the internal pores are high and thus can not be used as a precursor of the cathode material for a secondary battery. In addition, in order to reduce the troublesome processes such as the filtering process, it is necessary to uniformize the particle shape and distribution.

[Patent Document 1]: Patent Application No. 2010-0072259

Patent Document 2: Patent Application No. 2013-0068003

Patent Document 3: Patent Application No. 2013-0068434

The present invention provides a precursor production apparatus, a production method and a precursor produced therefrom, which are capable of improving the flow of a tailor-made reactor and thereby producing a high-density and low-particle-size cathode precursor.

Also provided are a precursor production apparatus and method, and a precursor produced therefrom, which can uniformly control precursor particle distribution and freely adjust precursor particle size.

Also provided are a precursor production apparatus and a production method and a precursor produced therefrom, wherein the concentration gradient is improved more effectively.

The precursor manufacturing apparatus of this embodiment includes an outer cylinder having an inlet formed at one side thereof and an outlet formed at the other side thereof, and an inner cylinder having an inner space. The inner cylinder of the outer cylinder is disposed concentrically and rotatably, A reactor to form a Taylor vortex in the reactor; A drive motor coupled to the spinneret to rotate the spinneret; A precursor starting material supply unit supplying precursor starting material to the inlet; A chelating agent supply for supplying a chelating agent; And a regulating agent supply unit for supplying a pH adjusting agent, wherein the reactor can be formed with a gap number (d / ri) of less than 0.05 to 0.2. Here, d = the gap between the inner circumferential surface of the outer cylinder and the outer circumferential surface of the toroid, and ri = the radius of the toroid.

And a control material supply unit for supplying the composition control material into the reactor.

The reactor may have a linear velocity of 1.58 m / s to 14 m / s.

The reactor may have a linear velocity of 6 m / s to 10 m / s.

The spinning device may have a rotational speed of 100 rpm to 1100 rpm.

The reactor may be provided with at least one or more control material supply portions arranged along the axial direction in the outer cylinder.

The reactor may have a fluid residence time of less than 1 hour to less than 4 hours.

The manufacturing apparatus may be an apparatus for manufacturing a cathode precursor for a secondary battery cathode material.

The precursor preparation method of this embodiment includes the steps of: providing a Taylor-Kuet reactor with a precursor starting material, a chelating agent and a pH adjusting agent; Rotating the spinneret of the reactor to co-react the precursor starting material; And a step of advancing the fluid between the outer cylinder of rotation of the reactor having a gap number (d / ri) of less than 0.05 and less than 0.2 to produce a concentration gradient precursor. Here, d is the gap between the inner circumferential surface of the outer cylinder of the reactor and the outer circumferential surface of the tuft, and ri = radius of the tuft.

The precursor starting material may be a sulphate, nitrate or chloride type material of Ni, Co, Mn.

The precursor starting material may be a sulphate, nitrate or chloride of Fe, which may be injected with phosphoric acid.

Wherein at least one selected from Ca, V, Cr, Cu, La, Sm, Gd, Zn, Fe, Al, Zr, Y, Ba, Mg, Ce and Ti is added to 100 parts by weight of the precursor More than 0 and 10 parts by weight or less.

The coprecipitation reaction may be carried out at a pH in the range of 8 to 12.

The chelating agent may be NH ₄ OH.

The pH adjusting agent may be NaOH.

The molar ratio of the calretting agent to the metal salt aqueous solution may be 0.5: 1 to 2.0: 1.

And injecting a composition control material of the precursor solution through an injection line installed in the outer cylinder.

The composition controlling material may include any one of nickel, cobalt, manganese, and aluminum.

The reaction temperature in the preparation of the precursor may be 40 to 70 ° C.

The reactor may have a linear velocity of 1.58 m / s to 14 m / s.

The reactor may have a linear velocity of 6 m / s to 10 m / s.

The rotational speed of the spinneret during the preparation of the precursor may be between 100 and 1100 rpm.

The fluid retention time within the reactor during the production of the precursor may be from 1 hour to less than 4 hours.

The precursor produced in this embodiment may be a cathode precursor for a cathode material of a secondary battery.

The precursor may have a tap density of 1.8 g / ml or more.

The precursor may be less than 7 microns in size.

The precursor may have a concentration difference of at least 8% between the inner core and the outer shell.

As described above, according to the present embodiment, by improving the internal space of the reactor to improve the flow of the reactant, it is possible to improve the phenomenon that the reactant stays in the reactor for a long time and to suppress abnormal growth. Thus, the particle size distribution is improved and a cathode precursor having a low particle diameter having a tap density usable for a secondary battery can be produced.

In addition, the flow of the fluid in the reactor is improved to prevent reverse flow, whereby a concentration gradient in the precursor is more effectively formed in the production of the concentration gradient type precursor, and a precursor having a gradient of 8% or more can be produced.

In addition, it is possible to control the size of the cathode precursor particle more freely by controlling the fluid flow in the reactor.

Further, the particle shape and distribution can be made more uniform, the filtering step after the cathode material manufacturing can be omitted, and the inconvenience of selecting only the anode material of the desired size can be reduced.

In addition, it becomes possible to continuously produce NMC precursors having a low particle diameter of less than 7 microns at a high density.

1 is a schematic view showing an electrode body manufacturing apparatus according to this embodiment.
2 is a schematic cross-sectional view for explaining the reactor structure in the electrode body manufacturing apparatus according to the present embodiment.
FIG. 3 is an electron micrograph of a precursor prepared according to the present embodiment in comparison with the prior art.
FIG. 4 shows the characteristics of the precursor produced according to this embodiment in comparison with the prior art.
FIG. 5 shows the results of the EDS analysis of the precursor prepared according to this example in comparison with the prior art.
FIGS. 7 and 8 show the performance of the cathode material manufactured according to the present embodiment in comparison with the conventional art.

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.

Figures 1 and 2 illustrate a reactor of a production apparatus and a production apparatus for producing a precursor according to this embodiment.

As shown in FIG. 1, the manufacturing apparatus of the present embodiment includes an outer cylinder 12 having an inlet 11 formed at one side thereof and an outlet 13 formed at the other side thereof, an inner cylinder 12 having an inner space, And a reactor (10) including a rotor (14) arranged and rotatably installed to form a quattroiler vortex between the rotor (14) and the outer cylinder (12). The apparatus also includes a drive motor 20 connected to the rotor 14 to rotate the rotor 14, a precursor starting material supply unit 30 for supplying the precursor starting material to the inlet 11, A chelating agent supply part 40 for supplying a chelating agent, a controlling agent supplying part 50 for supplying a pH adjusting agent, and a controlling material supplying part 60 for supplying a composition controlling material into the reactor 10.

The manufacturing apparatus can produce a cathode precursor for a cathode material of a secondary battery by using a rotating flow of the reactor 10.

As described above, in the reactor 10 using the Taylor vortex, the spacing between the outer cylinder and the inner rotating body is adjusted to suitably increase the number of the Taylor band rings. As a result, the reactor 10 conventionally used for manufacturing the cathode precursor The mixing phenomenon between the internal products can be minimized, and efficient discharge of the internal particles becomes possible. As a result, it is possible to continuously produce precursors having a gradient composition with a high density and a low particle diameter while preventing the generation of abnormal precursors.

Both ends of the outer cylinder 12 are formed by being clogged, and an inlet 11 and an outlet 13 are respectively formed. The outer cylinder 12 is fixedly mounted on the frame of the apparatus and the rotary shaft of the drive motor 20 is connected to the shaft center of the rotary shaft 14 through the tip of the outer cylinder 12. Thus, when the drive motor 20 is operated, the rotator 14 is rotated with respect to the fixed outer cylinder 12.

The feed line 17 connected to the inlet 11 is connected to the precursor starting material supply 30 and the chelating agent supply 40 and the regulator feed 50 to form a precursor starting material, A control line is connected to one side of the outer cylinder 12 of the reactor 10 and is controlled by the control material supply unit 60 through the injection line 19. [ Material is supplied.

In this embodiment, one injection line 19 is illustrated, but the present invention is not limited thereto. At least one of the injection lines may be arranged along the axial direction of the outer cylinder 12. In this embodiment, by adjusting the positions and the number of the injection lines, various kinds of regulating materials can be supplied to the outer cylinder to provide a concentration gradient, and a new material can be coated or doped on the surface of the precursor, .

The reactor 10 of this embodiment is, for example, a reactor for producing a precursor using a quat-Taylor flow. The reactor will be described in more detail with reference to FIG.

2, the reactor 10 includes an outer cylinder 12 disposed outside and having an inner space, a rotor 14 disposed inside the outer cylinder 12 and rotatably installed therein, . The outer cylinder 12 and the rotor 14 form a cylindrical shape. The rotary shaft 14 is disposed so as to be concentric with the central axis of the outer cylinder 12 and spaced apart from the inner peripheral surface of the outer cylinder 12 because the outer diameter thereof is smaller than the inner diameter of the outer cylinder 12. [

The space between the outer cylinder (12) and the rotor (14) is the area where the reaction for the production of the precursor takes place. Both ends of the reactor 10 constitute an inlet and an outlet. The fluid introduced into the inlet is discharged through the outlet at the other end. During this process, the reaction proceeds through the region between the rotor 14 and the outer cylinder 12 . Hereinafter, a space between the inner circumferential surface of the outer cylinder 12 and the outer circumferential surface of the rotator 14 is referred to as a reaction zone, and the direction in which the fluid flows in and out of the reactor 10 is referred to as a fluid advancing direction.

The reactor 10 rotates relative to the fixed outer cylinder 12 to form a vortex in the reaction zone between the rotor 14 and the outer cylinder 12. [

When the rotor (14) is rotated, a band-like flow is generated, and each band-like flow is rotated without being mixed. This flow is called a Couette-Taylor vortex or Taylor vortex. The Kuett-Taylor vortex refers to the fact that a specific flow characteristic is exhibited as one cylinder rotates when a fluid flows between two cylinders having the same center. In this embodiment, the inner rotor 14 rotates The fluids that are present near the rotor 14 due to centrifugal force tend to exit in the direction of the fixed outer cylinder 12 and as a result the fluid becomes unstable and is regular along the axial direction and rotates in the opposite direction A vortex of the high-paired array, that is, a Taylor vortex or a Kuett Taylor vortex, is formed.

The reactor 10 of the present embodiment may have a structure in which the number of gaps (d / ri) defining the interval between the inner circumferential surface of the outer cylinder 12 and the outer circumferential surface of the yoke is less than 0.05 to 0.2. Here, d = the gap between the inner circumferential surface of the outer cylinder and the outer circumferential surface of the toroid, and ri = the radius of the toroid.

Table 1 below shows the change in the number of band rings and the flow rate with respect to the number of gaps in a reactor having a radius of ri = 4.2 cm.

Gap number Number of band rings Flow rate 0.1 20 1.69 0.15 18 1.69 0.2 10 1.58 0.3 8 1.55 0.4 3 1.48

As shown in Table 1, as the number of gaps in the reaction region between the inner circumferential surface of the outer cylinder 12 and the outer circumferential surface of the rotator 14 decreases, the number of the Taylor belt rings increases. In addition, it can be seen that the magnitude of the flow velocity varies with the rotation speed of the same rotation. That is, it can be seen that the flow rate decreases when the number of the gap increases.

Thus, by reducing the number of gaps, the number of band rings and the flow velocity are increased, thereby improving the fluid flow. Thus, energy efficiency and mass transfer characteristics are improved while suppressing the formation of turbulence.

However, as the number of gaps increases, the number of band rings decreases and the back flow phenomenon increases as the size of the band rings by the Taylor flow increases. Accordingly, when the number of gaps in the reactor is out of the above range and is 0.2 or more, the size of the band loop due to the Taylor flow sharply increases and the back flow phenomenon becomes large. If the gap number is less than 0.05, the reverse flow control is good in the case of the Taylor band loop, but the reactor efficiency (precursor production volume / internal fluid volume) rapidly decreases.

Thus, in this embodiment, the reactor is formed with a gap number of less than 0.05 to 0.2 to increase the number of band rings, thereby improving fluid flow.

Conventional reactors are formed with a gap number of 0.2 to 0.4, and it is difficult to form a concentration gradient of 8% or more through the reactor of the conventional structure, and there is a limit in manufacturing precursors having a high density and a low particle diameter.

The reactor of the present embodiment improves the fluid flow structure by increasing the number of band rings by reducing the number of gaps in the conventional reactor and optimizing the rotational speed of rotation and the residence time of the reactant to uniformize the particle distribution, It becomes possible to produce a precursor.

In addition, in the course of manufacturing the precursor, the flow of fluid along the proceeding direction becomes more smooth and efficient discharge becomes possible. Thus, it is possible to inhibit the abnormal growth of some of the particles, which are generated as the reactants stay in the reactor for a long time in the reactor.

In this embodiment, the reactor may have a linear velocity of the internal fluid ranging from 1.58 m / s to 14 m / s. The linear velocity of the reactor can be understood as the flow velocity of the fluid flowing in the reaction zone of the reactor.

As the linear velocity of the reactor increases, the increased momentum maximizes the aggregation between the particles, resulting in higher tap density. Thus, in this embodiment, a precursor having a high density of 1.8 g / ml or more, which is difficult to realize through conventional reactors, can be manufactured with a low particle size by rotating the spinning furnace in the linear velocity range as described above.

When the linear velocity of the reactor is lower than 1.58 m / s, the tap density is drastically lowered, making it difficult to produce a high-density precursor. If the linear velocity of the reactor exceeds 14 m / s, the particle size of the precursor becomes too small, and the tap density is lowered.

In particular, in this embodiment, by forming the internal linear velocity of the reactor at 6 m / s to 10 m / s, a precursor having a low particle diameter of less than 7 microns can be produced more effectively.

In addition, the rotation speed of the spinning machine may be 100 to 1100 rpm.

When the rotational speed of the spinning apparatus is lower than 100 rpm, even if the number of the gaps of the reactor is reduced as much as possible, no belt-shaped Taylor flow is generated and the effect as a reactor is not exhibited at all. The effect of the reactor begins to appear as the rotational speed of the rotor reaches 100 rpm, and the effect is maintained up to 1100 rpm. If the rotational speed of the rotor exceeds 1100 rpm, even if the number of turns of the reactor is increased to the maximum, the turbulent flow of the Taylor flow is generated and the belt is destroyed and mixed to lose the effect of the reactor.

Further, in this embodiment, the residence time of the reactants in the reactor may be from 1 hour to less than 4 hours. Here, the residence time may be defined as a time period during which the material introduced into the reactor is discharged through the outlet, and may be defined as the reaction region volume of the reactor / the flow rate of the reactor per hour.

Thus, by controlling the residence time in the reactor to be less than 1 hour to less than 4 hours, it is possible to fundamentally block the back flow in the reactor.

When the residence time is longer than 4 hours, the mixing phenomenon of the reaction fluid becomes conspicuous, so that a gradual reaction from the inlet to the outlet of the reactor can not be expected. Thus, the quality of the precursor to be produced is the same as that of the conventional CSTR. If the retention time is less than 1 hour, the tap density is reduced and the desired high-density precursor can not be produced.

Thus, by controlling the rotation speed of the spinneret and the residence time of the reactant in the state of increasing the number of band rings by using a reactor having a gap number of less than 0.05 to 0.2, the concentration difference at the inlet and the outlet of the reactor, And it is possible to manufacture a concentration gradient precursor having a high density and a low particle diameter of 8% or more.

In order to produce a precursor of 1.8 g / ml or more and less than 7 microns in the prior art, it was possible to use a batch type reactor. However, as mentioned above, the precursor of high density and low particle diameter was continuously .

Hereinafter, a process of manufacturing the cathode precursor from the above apparatus will be described.

The preparation of the precursor of this embodiment comprises the steps of supplying the precursor precursor starting material, chelating agent and pH adjusting agent through the inlet 11 of the precursor producing device, rotating the toroidal 14 to coprecipitate the precursor precursor starting material, The process proceeds to advance the fluid through the reaction zone between the outer cylinder 12 and the rotor 14 of the reactor 10 to produce a concentration gradient type cathode precursor.

This embodiment controls the reverse flow by controlling the rotational speed and the residence time of the reactant by forming the number of gaps between the outer cylinders of the reactor in the process of producing the precursor to less than 0.05 to 0.2 and adjusting the rotation speed and the residence time of the reactant to achieve a tap density of 1.8 g / It is possible to produce a high-density precursor having a concentration gradient of at least 7% at a low particle diameter of less than 7 microns.

The coprecipitation reaction refers to the simultaneous precipitation of various different ions into an aqueous solution or a non-aqueous solution. That is, a method of simultaneously precipitating two or three elements in an aqueous solution by neutralization reaction to obtain a precursor in the form of hydroxide or oxide, mixing the precursor with lithium hydroxide, and calcining the precursor.

The precursor precursor starting material enters the reactor through the inlet at a concentration of 1.0 to 4.0 M from the precursor feed. Particularly, when the cathode precursor starting material is 2.0 to 2.5 M, good quality can be obtained in terms of tap density and surface shape, and the effect is good.

As a starting material for preparing the ternary anion precursor, a substance in the form of sulfate, nitrate or chloride of Ni, Co, Mn can be introduced. In order to prepare the FePO ₄ precursor which is an olivine-type cathode precursor, a sulfate, nitrate or chloride form of Fe may be added together with phosphoric acid.

In addition to the starting material for the positive electrode electrode, Ca, V, Cr, Cu, La, Sm, Gd, Zn, Fe, F, Al, Zr, Y, Ba, Mg, Ce, To less than 10 parts by weight. The surface coating effect of the precursor can be expected by the above additives.

The additive can be fed through a feed line installed at the inlet of the reactor and is more effective when injected between the inlet and the outlet of the reactor through the feed line.

When the additive is added in an amount exceeding 10 parts by weight, a coating effect is not exhibited and a composite-like effect is exhibited, so that the electrical characteristics such as the reduction of the electric capacity of the electrode material may be reduced.

The molar ratio of the chelating agent to the metal salt aqueous solution may be 0.5: 1 to 2.0: 1. When the molar ratio of the chelating agent to the aqueous metal salt solution is less than 0.5: 1, the surface morphology becomes very poor and the porosity becomes high due to the rapid precipitation of the precursor. When the molar ratio of the chelating agent to the metal salt aqueous solution is higher than 2.0: 1, the particles can grow large and the quality is not a problem. However, since it is difficult to expect high precipitation of metal ions, the precipitation efficiency is lowered, Higher concentrations of the grading agent result in a significant increase in waste water treatment costs. NH ₄ OH may be used as the chelating agent in this embodiment.

The coprecipitation reaction may be carried out at a pH in the range of 8 to 12. The pH is more effective between 10.0 and 11.7. If the pH is lower than 8, the precipitation is not uniform and the composition is not uniform. When the pH is higher than 12, the powder does not show a spherical shape due to poor cohesiveness of the powder. Therefore, .

In order to adjust the pH, an appropriate amount of the pH adjusting agent is introduced into the reactor 10 from the pH adjusting agent supplying unit 50 to adjust the pH. In this embodiment, NaOH may be used as the pH adjusting agent.

In addition, the composition control material of the precursor solution may be injected into the reactor through an injection line connected to the outer cylinder. The composition controlling material may include any one of nickel, cobalt, manganese, and aluminum.

The injected precursor precursor material is subjected to a coprecipitation reaction at a reaction temperature of 40 to 70 ° C. If the temperature in the reactor 10 exceeds 70 ° C, the reaction rate is fast, but the oxidation of manganese is promoted and the quality of the precursor deteriorates. At a temperature lower than 40 ° C, the reaction rate is slow and the precursor is not formed.

In the precursor preparation process of this embodiment, the linear velocity of the internal fluid during operation of the reactor 10 may be from 1.58 m / s to 14 m / s.

Through such a manufacturing process, a precursor having a high density and a low particle diameter of 1.8 g / ml or more and less than 7 microns can be continuously produced. Further, by controlling the number of gaps, rotation speed or residence time of the reactor, precursors having various particle sizes and densities and concentration gradients of 8% or more can be produced.

[Example 1] Preparation of low-particle-diameter cathode precursor

In the production of the cathode precursor of Example 1, a production apparatus equipped with a reactor in which the number of gaps between the outer cylinders was set to 0.1 was used. In Comparative Example 1, a precursor was produced using a production apparatus equipped with a reactor having a gap number of 0.2. In both Example 1 and Comparative Example 1, the flow rate of the fluid inside the reactor was set to 2.8 m / s to prepare a precursor.

The precursor was prepared in the same conditions as in Example 1 and Comparative Example 1 as described below. NiSO ₄ , MnSO ₄ , and CoSO ₄ were mixed at a ratio of 3 kinds to prepare a precursor solution having 2M cations. The precursor solution was prepared so that the ratio of nickel (Ni), cobalt (Co), and manganese (Mn) was 6: 2: 2 in molar ratio using nickel sulfate, manganese sulfate and cobalt sulfate hydrate. A 1 M solution of cobalt sulfate was used as the material. The precursor solution was introduced at the rate of 2 hours residence time (3.96 ml / min when the gap number was 0.2) through the inlet of the apparatus, and 28% ammonia solution was added at 1/14 of the precursor solution. The internal pH of the reactor was maintained between 11.0 and 11.5 using 4M NaOH and the reaction temperature was between 45 and 55 ° C using a thermostat.

A sample was sampled after 36 hours after the precursor starting material was introduced, and the resultant was filtered using a 0.5 micron filter to prepare a cathode precursor.

Each of the cathode precursors prepared from Example 1 and Comparative Example 1 was observed with an electron microscope and the particle size distribution was analyzed using a particle size analyzer. The prepared cathode precursor was dried at 60 to 120 ° C for one day, and then subjected to 1,000 times impact in accordance with the process test method to measure the tap density with a tap density meter.

Fig. 3 shows the shape and particle size distribution of the precursor of Example 1 and Comparative Example 1 observed using an electron microscope, and Fig. 4 shows the change in characteristics of Example 1 and Comparative Example 1 in comparison.

As shown in Figs. 3 and 4, in Comparative Example 1, the particle size of less than 7 microns was obtained, but the shape was irregular, and the particle size distribution width was very large, 7.0. On the contrary, in the case of Example 1 in which the number of gaps was set to 0.1, the precursor was produced in an average particle size of less than 7 microns despite the same retention time, and the shape is very regular. The particle size distribution (width) is also homogeneous at 3.4. In the case of the tap density, it was confirmed that the number of gaps was reduced from 2.0 in Example 1 to 1.4 in Comparative Example 1.

That is, it can be seen that mixing of the products in the band ring is suppressed in manufacturing the cathode precursor by controlling the number of gaps through the first embodiment, and it is possible to manufacture the cathode precursor with a low particle diameter and high density.

[Example 2] Gradient cathode material manufacturing

In the production of the cathode precursor of Example 2, a manufacturing apparatus having a reactor capable of forming gradients and having a gap number of 0.1 between the rotating outer cylinders was used. The rotational speed of the reactor was set to 1100 rpm to prepare a precursor.

In Comparative Example 2, a precursor was prepared using a production apparatus equipped with a reactor having a gap number of 0.2 and a gradient.

Both the Example and the Comparative Example 2 were produced under the same conditions as described below. NiSO ₄ , MnSO ₄ , and CoSO ₄ were mixed at a ratio of 3 kinds to prepare a precursor solution having 2M cations. The precursor solution was prepared so that the ratio of nickel (Ni), cobalt (Co), and manganese (Mn) was 6: 2: 2 in molar ratio using nickel sulfate, manganese sulfate and cobalt sulfate hydrate. A 1 M solution of cobalt sulfate was used as the material. The precursor solution was introduced at the rate of 4 hours residence time (1.98 ml / min when the gap number was 0.2) through the inlet of the apparatus, and the control substance cobalt precursor was introduced at a flow rate of 1/10 of the precursor solution amount. Na ₄ OH, a chelating agent, was injected at a rate of 1/4 of the precursor solution while the rotation speed of the spinneret was maintained at 1100 rpm. The internal pH of the reactor was maintained between 11.0 and 11.5 using 4M NaOH and the reaction temperature was between 45 and 55 ° C using a thermostat. A sample was sampled after 36 hours after the precursor starting material was introduced, and the resultant was filtered using a 0.5 micron filter to prepare a cathode precursor.

In order to analyze the nickel concentration gradient of each of the positive electrode precursors prepared from Example 2 and Comparative Example 2, EDS analysis was performed from the center to the outer portion after performing end face processing by using a focused ion beam for the manufactured whole body, .

The chart in FIG. 5 shows the change in nickel fraction in the NMC precursor of Example 2 and Comparative Example 2 through the EDS analysis result. Here, the nickel molar fraction = [nickel molar concentration / (nickel molar concentration + cobalt molar concentration + manganese molar concentration)] * 100. The measurement points for the analysis were measured at each point equally divided into 10 equal parts from the inner center to the surface with respect to the section of the precursor.

As shown in FIG. 5, in the case of Example 2 produced from the reactor to which the gap number of 0.1 was applied, the internal nickel mole fraction was 58.51%, and it was continuously decreased to be 42.21% on the surface. Thus, it can be seen that the concentration gradient of about 16% or more is observed in the second embodiment due to a rapid concentration change.

On the contrary, in Comparative Example 2, it can be seen that only a concentration gradient of about 8% was possible with a fraction of nickel mole fraction of 58.44% at the inside and 50.28% at the surface portion.

From these experimental results, it can be seen that the backward movement of the precursor material is effectively blocked by minimizing the number of gaps, and thus the concentration gradient is effectively made and the precursor characteristics are improved.

FIGS. 6 and 7 show the performance of the anode prepared after the preparation of the gradient anode according to Example 2 and Comparative Example 2. FIG.

The precursors prepared in Example 2 and Comparative Example 2 were dried in an oven, 10 g was taken, mixed with LiOH, and then calcined under an oxygen atmosphere to give a composition of Li 1.03Ni0.6Mn0.2Co0.2O2. The fabricated products were fabricated in the shape of a coin cell and their cycle characteristics and impedance characteristics were measured in the range of 3.0 to 4.3V. Fig. 6 shows the change in the capacity according to the cycle, and Fig. 7 shows the change in efficiency according to the cycle.

As shown in FIGS. 6 and 7, when a positive electrode was prepared from the precursor prepared in Example 2, a positive electrode material having a high concentration gradient and a uniformly uniform quality was produced, The efficiency reduction is low.

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: Reactor 11: Entrance
12: outer cylinder 13: outlet
14: Tradition 16: Euro
17: supply line 19: injection line
20: Driving motor

Claims (24)

An outer cylinder having an inlet formed at one side thereof and an outlet formed at the other side thereof, an outer cylinder having an inner space, and a rotator disposed concentrically within the outer cylinder and rotatably installed therein to form a Taylor vortex between the rotary outer cylinder A reactor;
A drive motor coupled to the spinneret to rotate the spinneret;
A precursor starting material supply unit supplying precursor starting material to the inlet;
A chelating agent supply for supplying a chelating agent; And
and a pH control agent,
Wherein the reactor has a gap number (d / ri) of less than 0.05 to less than 0.2.
D is the gap between the inner circumferential surface of the outer cylinder and the circumferential surface of the yoke, and ri = radius of the yoke. The method according to claim 1,
And a control material supply unit for supplying a composition control material into the reactor. 3. The method of claim 2,
Wherein the reactor is provided with at least one or more regulating material supply portions arranged along the axial direction in an outer cylinder. 4. The method according to any one of claims 1 to 3,
Wherein the reactor has a linear velocity of 1.58 m / s to 14 m / s. 4. The method according to any one of claims 1 to 3,
Wherein the reactor has a linear velocity of from 6 m / s to 10 m / s. 5. The method of claim 4,
Wherein the spinning device has a rotation speed of 100 to 1100 rpm. 5. The method of claim 4,
Wherein the reactor has a fluid retention time of less than 1 hour to less than 4 hours. Supplying a precursor starting material, a chelating agent and a pH adjusting agent to a tailor-made reactor; Rotating the spinneret of the reactor to co-react the precursor starting material; And a step of advancing the fluid between the outer cylinder of rotation of the reactor having a gap number (d / ri) of less than 0.05 and less than 0.2 to produce a concentration gradient precursor.
D is the gap between the inner circumferential surface of the outer cylinder of the reactor and the outer circumferential surface of the tuft, and ri = radius of the tuft. 9. The method of claim 8,
Wherein at least one selected from Zn, Fe, F, Al, Zr, and Y is added to the precursor precursor starting material in an amount of 0 to 10 parts by weight based on 100 parts by weight of the precursor. 10. The method of claim 9,
Further comprising injecting a composition controlling material of the precursor solution through an injection line provided in the outer cylinder. 11. The method of claim 10,
Wherein the composition controlling material comprises any one of nickel, cobalt, manganese, and aluminum. The method according to any one of claims 8 to 11,
Wherein the linear velocity of the reactor during the production of the precursor is 1.58 m / s to 14 m / s. The method according to any one of claims 8 to 11,
Wherein the linear velocity of the reactor during the production of the precursor is from 6 m / s to 10 m / s. 13. The method of claim 12,
Wherein the spinning speed of the spinneret during the production of the precursor is 100 to 1100 rpm. 13. The method of claim 12,
Wherein the fluid retention time of the reactor in the production of the precursor is less than 1 hour to less than 4 hours. 16. The method of claim 15,
Wherein the cathode precursor starting material is a sulfate, nitrate or chloride type material of Ni, Co, Mn. 17. The method of claim 16,
Wherein said precursor precursor material is a precursor of Fe, wherein the sulfate, nitrate or chloride of Fe is co-injected with phosphoric acid. 16. The method of claim 15,
Wherein the chelating agent is < _{RTI ID = 0.0} > NH4OH. ≪ / _RTI > 16. The method of claim 15,
Wherein the pH adjusting agent is NaOH. 16. The method of claim 15,
Wherein the reaction temperature during the production of the precursor is 40 to 70 占 폚. 16. The method of claim 15,
Wherein the coprecipitation reaction is carried out at a pH in the range of 8 to 12. 16. The method of claim 15,
Wherein the molar ratio of the calretting agent to the metal salt aqueous solution is 0.5: 1 to 2.0: 1. 11. A precursor produced by any one of claims 1 to 3 and 8 to 11 having a tap density of at least 1.8 g / ml and a size of less than 7 microns. 24. The method of claim 23,
Wherein the precursor has a concentration difference of at least 8% between the inner core and the outer shell.

Images