KR101172867B1 - Method for fabricating precursor of cathode active material used in lithium secondary battery - Google Patents

Abstract

The present invention is characterized by producing a positive electrode active material precursor using an improved Kuet-Taylor vortex reactor. The improved Kuet-Taylor reactor consists of an outer cylinder 51 and an inner cylinder 53 sharing the longitudinal axis 54 together with a fluid passage 52 between the outer cylinder 51 and the inner cylinder 53. A double cylinder structure is formed to form an empty, one of the outer cylinder 51 and the inner cylinder 53 has a circular cross section perpendicular to the longitudinal axis 54 and the other cross section perpendicular to the longitudinal axis 54. The elliptical shape, the fluid flow in the fluid passage 52 in the vortex form through the relative rotational movement of the outer cylinder 51 and the inner cylinder 53 having the longitudinal axis 54 as the rotation axis, the outer cylinder ( Inlet ports 61a, 61b, and 61c communicating with the fluid passage 53 are provided at the front end of the fluid passage 53, and outlet ports 62a, 62b, which communicate with the fluid passage 53 at the rear end of the outer cylinder 51, respectively. 62c) is provided, the outer cylinder 51 is provided with a temperature adjusting means (51a) for controlling the temperature of the fluid passage (53).

Description

Method for fabricating a cathode active material precursor for a lithium secondary battery {Method for fabricating precursor of cathode active material used in lithium secondary battery}

The present invention relates to a method for producing a positive electrode active material precursor for a lithium secondary battery, in particular, by using a double-cylindrical vortex reaction device to promote the production reaction to lower the reaction temperature and reduce the reaction time as well as uniform crystal grains of the positive electrode active material The present invention relates to a method for producing a positive electrode active material precursor for a lithium secondary battery, which is also easy for mass production.

Since the positive electrode active material of a lithium secondary battery is a very important factor that determines the performance, lifespan, and capacity of the battery, the trend of developing a technology that can reliably and mass-produce a positive electrode active material in accordance with the rapidly increasing demand of the secondary battery market. to be.

The charge and discharge capacity of the positive electrode depends on the particle size and particle structure of the active material. That is, the smaller the particle size of the active material is, the faster the diffusion of lithium ions increases, thus increasing the charge / discharge capacity of the positive electrode, and the charge / discharge capacity of the positive electrode itself increases even when the particle structure easily diffuses the lithium ions. In addition, since the stability of the crystal structure is closely related to the reversibility, it has a great influence on the battery life.

Lithium cobalt oxide (LiCoO2) was mainly used as a positive electrode active material of a lithium secondary battery. Currently, lithium nickel oxide (Li (Ni-Co-Al) O2) and lithium composite metal oxide (Li (Ni-Co) are used as other layered positive electrode active materials. -Mn) O2) and the like, in addition to low-cost high-stable spinel-type lithium manganese oxide (LiMn2O4) and olivine-type iron phosphate compound (LiFePO4) has attracted attention.

As a method of synthesizing such a material, in the case of commercial lithium cobalt oxide (LiCoO 2), a solid phase method of synthesizing the solid phase reaction of raw materials at 800 to 1000 ° C. is used. This is because the solid state method generally uses inexpensive raw materials such as metal oxides, hydroxides, and carbonates as raw materials, and is suitable for mass production and generally has excellent cycle performance.

In general, the solid phase method consists of mixing a raw material of lithium and cobalt to produce a pellet (pellet) of the mixture and heat-treating it for about 20 to 24 hours at 800 ~ 1000 ℃ in air and pulverizing the pellet. In addition, the pulverized oxide is pelletized again and subjected to several heat treatment / grinding processes.

However, as can be seen in the synthesis process, since the solid phase reaction of the raw material must be used, the synthesis temperature must be high, and the heat treatment time is also long because the diffusion distance between the raw materials is long. Furthermore, to achieve homogeneity during the synthesis process, several heat treatments and grinding processes are required.

In order to solve the problems of the solid-phase method, various synthesis processes such as synthesis of lithium metal oxides by synthesis of low temperature, liquid phase reaction of raw materials, or preparation of homogeneous precursor materials from liquid phase and heat treatment thereof are studied. have.

Typically sol-gel method, coprecipitation method, hydrothermal synthesis, ion exchange reaction under hydrothermal condition, mechanical alloying, ultrasonic spray pyrolysis spray pyrolysis) and the reflux reaction.

As described above, various methods for preparing a multi-component metal oxide-based positive electrode active material precursor have been proposed, but co-precipitation using multi-component metal salts such as nickel, cobalt, manganese, and aluminum as starting materials is the most economical and practical. It is considered the way.

Japanese Patent Application Laid-Open No. 07-335214, Japanese Patent Application Laid-Open No. 08-225328, Japanese Patent Application Laid-Open No. 11-312519, etc., which prepare a positive electrode active material precursor for a nickel and manganese two-component lithium secondary battery using a coprecipitation method at a pH of 12 or more. Here's how.

In Korean Patent Publication No. 2002-54534, a mixed metal salt solution containing nickel, cobalt, and manganese as a main component in a coprecipitation reactor containing distilled water was injected at a constant speed so that the particle residence time was 3 to 10 hours at a concentration of 1.5 to 3.0 M. In addition, while injecting an aqueous ammonia solution at a constant speed such that the molar ratio of ammonia and metal salt is 1 to 4, particles are produced by adjusting the reaction temperature to 30 to 50 ° C. and the pH to 11.0 to 11.99, and the resulting particles overflow. The present invention provides a method for preparing a precursor prepared through a process of collecting, washing, filtration and drying.

On the other hand, a method of manufacturing a three-component active material of nickel, cobalt, aluminum with aluminum in addition to manganese using a coprecipitation method is disclosed in Japanese Patent Laid-Open No. 08-225328.

However, the multi-component precursors prepared by the aforementioned coprecipitation method have a large particle size distribution of particles obtained by the long residence time in the coprecipitation reactor and contain a large amount of fine particles, which makes it difficult to prepare uniform particles. It has disadvantages such as a large amount of alkali salts which are generated side reactions.

Although a coprecipitation reactor capable of producing coprecipitation particles composed of spherical particles and having a high tap density has been proposed in Korean Patent Application Publication No. 2010-59601 (Coprecipitation Reactor, 2010.06.04.), The efficiency is still questioned. Therefore, the present invention is to use a Kuet-tailed vortex reaction apparatus that can produce a cathode active material precursor for a lithium secondary battery more advantageous than the conventional coprecipitation reactor by generating a cue-tailed vortex in the reactor to promote the reaction do.

1 to 4 are diagrams for explaining a conventional Kuet-Taylor vortex reactor, FIG. 1 is a schematic view, FIG. 2 is a side cross-sectional view of FIG. 1, and FIG. 3 is taken along line AA ′ of FIG. 1. 4 is a cross-sectional view illustrating a change in width d of the fluid passage 152 over time and a change in linear velocity v along the vertical axis.

1 to 3, the conventional Kuet-Taylor vortex reactor includes an outer stationary cylinder 151 and an inner rotating cylinder 153 rotating therein. The inner rotating cylinder 153 has a rotating shaft 154 coinciding with the longitudinal axis of the outer fixed cylinder 151. The inner rotating cylinder 153 and the outer fixed cylinder 151 are installed to be spaced apart from each other at a predetermined interval (d), the fluid passage 152 through which the reaction liquid flows between the inner rotating cylinder 153 and the outer fixed cylinder 151. Is formed.

When the inner rotating cylinder 153 rotates, the fluid located in the inner rotating cylinder 153 side of the fluid passage 152 tends to go toward the outer fixed cylinder 151 by centrifugal force, which causes the fluid to become unstable. Along the axis of rotation 154 is formed a vortex 155 of a ring pair arrangement which rotates in a regular and opposite direction. Do this with Taylor or Kuet-Taylor vortex.

In the above-described conventional Kuet-Taylor vortex reactor, as shown in FIG. 3, the vertical cross section of the inner rotating cylinder 153 with respect to the rotating shaft 154 has the same circular shape as the outer fixed cylinder 151, and thus the outer fixed cylinder. Since the 151 and the inner rotating cylinder 153 are arranged concentrically, as shown in FIG. 4A, the inner stationary cylinder 151 rotates at a specific position, for example, inside point A, while the inner rotating cylinder 153 rotates. The interval d between the rotating cylinder 153 and the external fixed cylinder 151 is constant without changing with time. In addition, since the diameter of the inner rotating cylinder 153 does not change along the rotating shaft 154, the linear velocity v of the inner rotating cylinder 153 does not change along the rotating shaft 154, as shown in FIG. Therefore, the situation in the fluid passage 152 is constant over time or along the axis of rotation 154, so that the vortex is generated only by the relative rotation between the inner rotating cylinder 153 and the outer fixed cylinder 151. There is a limit to the fluidity of.

The problem to be solved by the present invention, by improving the conventional Kuet-Taylor vortex reaction apparatus and using it to promote the reaction of the production of the positive electrode active material precursor for lithium secondary batteries to lower the reaction temperature and reduce the reaction time of the product The present invention provides a method for producing a cathode active material precursor for a lithium secondary battery in which crystal grains are small, uniform, and advantageous in mass production.

Method for producing a cathode active material precursor for a lithium secondary battery according to the present invention for achieving the above object is characterized by using an improved vortex reactor.

An example of the improved vortex reaction device is made of an outer cylinder and an inner cylinder that share the longitudinal axis, but has an empty double cylinder structure to form a fluid passage between the outer cylinder and the inner cylinder, wherein any one of the outer cylinder and the inner cylinder is The cross section perpendicular to the longitudinal axis has a circular shape, and the other cross section perpendicular to the longitudinal axis has an elliptical shape, and the fluid in the fluid passage through the relative rotational movement of the outer passage inner cylinder formed with the longitudinal axis as the rotation axis. The vortex flows, and the front end of the outer cylinder is provided with an inlet port communicating with the fluid passage and the rear end of the outer cylinder is provided with an outlet port communicating with the fluid passage, the inner cylinder or the outer The cylinder is provided with a temperature control means for controlling the temperature of the fluid passage.

Another example of the improved vortex reaction device is composed of an outer cylinder and an inner cylinder that share the longitudinal axis, but has an empty double cylinder structure to form a fluid passage between the outer cylinder and the inner cylinder, and the outer cylinder and the inner cylinder are along the longitudinal axis. The sidewalls of the outer and inner cylinders are inclined at the same inclination so as to be spaced apart from each other at regular intervals, and the fluid flows in the fluid passage in a vortex form through the relative rotational movement of the outer and inner cylinders having the longitudinal axis as the rotation axis. The front end of the outer passage is provided with an inflow port communicating with the fluid passage, the rear end of the outer passage is provided with an outlet port communicating with the fluid passage, the inner passage or the outer passage temperature of the fluid passage Temperature control means for controlling the is installed.

 The present invention manufactures a positive electrode active material precursor using the improved vortex reaction apparatus as described above, specifically, the metal salt aqueous solution, the basic aqueous solution, and the aqueous ammonia solution as a source material into the inlet port to rotate relative to the inner passage A first step of causing mixing and reaction in the fluid passage by movement; And a second step of obtaining the positive electrode active material precursor which is a result of the reaction in the fluid passage is discharged to the outlet port. It includes.

Cobalt (Co), Mn (manganese), nickel (Ni), aluminum (Al), cobalt (Co), manganese (Mn), aluminum (Al), magnesium (Mg), copper (Cu), 0.5 M metal salt containing at least one metal selected from the group consisting of zinc (Zn), iron (Fe), vanadium (V), chromium (Cr), titanium (Ti), tungsten (W) and molybdenum (Mo) It can be used dissolved in water at a concentration of 4M. The metal salt may be sulfate, nitrate, acetate, chloride, or phosphate.

As said basic aqueous solution, the sodium hydroxide aqueous solution or the potassium hydroxide aqueous solution of 1M-8M can be used.

As the aqueous ammonia solution, it is preferable to use an aqueous 15% to 30% ammonia solution, and it is preferable to add 1 to 20% by volume of the entire source material.

The relative rotational movement of the outer passage inner cylinder in the first step is made by the outer cylinder is fixed and the inner cylinder rotates at 10 ~ 5000rpm, the mixing and reaction in the fluid passage is 30 ~ It is preferable to carry out on 60 degreeC and the conditions of pH 10-12.

It is preferable that a plurality of outlet ports are provided to be arranged in series in the longitudinal axis direction.

A plurality of inflow ports may be provided and the metal salt aqueous solution, the basic aqueous solution, and the ammonia aqueous solution may be independently supplied to each inflow port, and the plurality of inflow ports may be relatively positioned in front of the inlet port. The metal salt aqueous solution, the basic aqueous solution and the aqueous ammonia solution are introduced through the inlet port, and the inlet port located relatively backwards may serve as a return port for returning to the inlet port located relatively forward.

It is preferable that a spiral protruding screw projecting in a screw shape is provided at any one of the inner surface of the inner cylinder and the outer surface of the outer cylinder.

The inlet port may include a plurality of metal salt inlet ports for injecting the aqueous metal salt solution, in which case it is preferred that the metal salt aqueous solution having a different composition of the metal salt is introduced through each of the metal salt inlet ports. At this time, the inlet port is preferably provided with a metal salt inlet port for injecting the aqueous metal salt solution, the basic aqueous solution inlet port for injecting the basic aqueous solution, and the ammonia aqueous solution inlet port for injecting the aqueous ammonia solution. The basic aqueous solution inlet port may be provided in plural numbers so as to correspond to the respective metal salt inlet ports, and the basic aqueous solution inlet port and the metal salt inlet port may be installed to face each other. .

A return inlet port may be provided at the front end of the outer cylinder, in which case the reaction product coming out of the outlet port is returned to the return inlet port. At this time, it is preferable that a plurality of outlet ports are provided, some of which are used to return the reaction product to the return inlet port.

According to the present invention, since uniform mixing and reaction are caused by the vortex, the reaction of the formation of the positive electrode active material precursor is promoted as compared with the conventional case, so that the reaction temperature is low, the reaction time is reduced, and the crystal grains of the precursor are small and uniform. It is also advantageous for mass production. Since the charge and discharge capacity of the positive electrode varies depending on the particle size and particle structure of the active material, it is very important to control the particle size and crystal structure.

1 is a schematic diagram illustrating a conventional Kuet-Taylor vortex reactor;
2 is a side cross-sectional view of FIG. 1;
3 is a cross-sectional view taken along line AA ′ of FIG. 1;
4 is a view for explaining a change in width d of the fluid passage 152 of FIG. 1 and a change in linear velocity v along the longitudinal axis;
5 is a schematic view for explaining an improved Kuet-Taylor vortex reaction apparatus used in the first embodiment of the present invention;
6 is a cross-sectional view taken along the line AA ′ of FIG. 5;
FIG. 7 is a graph for explaining a change in width d of the fluid passage 52 according to the time of FIG. 5;
8 to 11 are views for explaining a method for producing a positive electrode active material precursor according to the present invention using the apparatus of FIG.
FIG. 12 is a view for explaining a case in which the protruding screw 64 is further installed in FIG. 5; FIG.
13 is an improved Kuet-Taylor vortex reactor for use in the second embodiment of the present invention.
FIG. 14 is a graph for explaining a change in the linear velocity v in the longitudinal axis direction of FIG. 13.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are merely provided to understand the contents of the present invention, and those skilled in the art will be able to make many modifications within the technical scope of the present invention. Therefore, the scope of the present invention should not be construed as being limited to these embodiments.

Example 1

5 to 12 are views for explaining a method of manufacturing a positive electrode active material precursor for a lithium secondary battery according to a first embodiment of the present invention, unlike the conventional case when an inner cylinder uses an elliptical cylinder instead of a cylinder. 5 is a schematic diagram of an improved Kuet-Taylor vortex reactor for use in the first embodiment of the present invention, FIG. 6 is a cross-sectional view taken along line AA ′ of FIG. 5, and FIG. 8 is a graph illustrating a method of manufacturing a positive electrode active material precursor, and FIG. 12 is a diagram illustrating a protruding screw 64.

5 and 6, the vortex reaction apparatus used in the first embodiment of the present invention includes an outer fixed cylinder 51 and an inner rotary ellipse 53 rotating therein. The inner elliptic cylinder 53 has a rotating shaft 54 coinciding with the longitudinal axis of the outer fixed cylinder 51. The inner rotary elliptic cylinder 53 is inserted into the outer fixed cylinder 51 in parallel to the outer fixed cylinder 51 so as to be spaced apart from the inner surface of the outer fixed cylinder 51 by a predetermined interval.

The inner rotary ellipse cylinder 53 has a constant diameter without changing the diameter along the rotary shaft 54 and the cross section perpendicular to the rotary shaft 54 has an elliptic shape, rather than a circular shape as in the related art. Therefore, the inner rotary cylinder 53 and the outer fixed cylinder 51 maintains a constant distance (d) along the longitudinal axis of the outer fixed cylinder (51).

Since the inner rotary ellipse cylinder 53 has a plate shape, it may be rather undesirable to generate a Kuet-Taylor vortex, so that the inner rotary ellipse cylinder 53 has a short axis diameter (a) and a longitudinal axis perpendicular to the rotary shaft 54. It is preferable that the ratio of the diameter (b) is elliptical having a range of 1 <b / a <20.

The inner rotary elliptical cylinder 53 has an elliptical shape in a vertical section with respect to the rotary shaft 54, so that the inner rotary elliptical cylinder at a specific position (A) of the outer fixed cylinder 51 is rotated while the inner rotary elliptical cylinder 53 rotates. The interval d between the 53 and the external fixing cylinder 51 is changed into a periodic sinusoidal shape with time as shown in FIG. Therefore, new variables are added to the fluctuations of the fluid as compared to the conventional case, so that the vortex flow in the fluid passage 52 becomes more active and uniform.

In FIG. 5, the rotating elliptic cylinder 53 is installed inside and the fixed cylinder 51 is installed outside, but the rotating cylinder is installed inside, and the fixed elliptic cylinder may be installed outside. A fixed ellipsoid may be installed inside and a rotating cylinder may be installed outside.

Referring to FIG. 8, inlet ports 61a, 61b, and 61c communicating with the fluid passage 52 are provided at the front end of the external fixing cylinder 51, and an outlet port communicating with the fluid passage 52 at the rear end thereof. 62a, 62b, 62c are provided. The external fixing cylinder 51 is provided with a temperature adjusting means 51a for controlling the temperature of the fluid passage 52.

Through the three inlet ports 61a, 61b, 61c, metal salt aqueous solution (A1), basic aqueous solution (A2), and ammonia aqueous solution (A3) are introduced as source raw materials, respectively. As the metal salt aqueous solution, cobalt (Co), Mn (manganese), nickel (Ni), aluminum (Al), cobalt (Co), manganese (Mn), aluminum (Al), magnesium (Mg), copper (Cu), zinc Sulfates, nitrates, acetates containing one or more metals selected from the group consisting of (Zn), iron (Fe), vanadium (V), chromium (Cr), titanium (Ti), tungsten (W) and molybdenum (Mo) Metal salts such as chloride, phosphate, and the like dissolved in water at a concentration of 0.5M to 4M may be used. As the basic aqueous solution, 1M to 8M sodium hydroxide solution or potassium hydroxide solution may be used. It is preferable to use 15-30% aqueous ammonia solution (NH4OH), and it is preferable to add 1-20% by volume of the total source material.

Since the metal salt aqueous solution (A1), the basic aqueous solution (A2), and the aqueous ammonia solution (A3) should be added as the source material, three inflow ports 61a, 61b, and 61c are provided, but are not necessarily limited thereto. Different types of source materials may be premixed and then introduced through one inlet port.

 In the fluid passage 52, the metal salt aqueous solution (A1) and the basic aqueous solution (A2) react to form a single component metal oxide system such as Co (OH) 2, Ni (OH) 2, Mn (OH) 2, MnNiCo (OH) 2, or the like. Alternatively, the multicomponent metal oxide-based positive electrode active material precursor is formed in a uniform particle shape.

At this time, the inner member ellipsoid 53 is rotated at 10 ~ 5000rpm, the thickness (d) of the fluid passage 52 is 0.1 ~ 100cm, so that the sample is mixed under the conditions of 30 ~ 60 ℃ and pH 10 ~ 12 It is desirable to.

At least one of the inflow port and the outflow port is arranged in series in the longitudinal axis direction of the external fixing cylinder 51 so that the distance between the inflow port and the outflow port can be selected according to which inflow port and the outflow port are used. It is preferable. In FIG. 8, three inflow ports 61a, 61b, and 61c are all on the same starting line, and a plurality of outlet ports 62a, 62b and 62c are arranged in series in the longitudinal axis direction. It is preferable to select one of the plurality of outlet ports 62a, 62b, 62c in consideration of the flow rate and the reaction conditions such that the fluid passage 52 reacts for an average residence time of 0.5 to 2 hours.

When the reaction takes place in the fluid passage 52, the space d between the inner rotary elliptical cylinder 53 and the outer fixed cylinder 51 changes into a sine wave shape periodically, so that the flow of the vortex is more active and uniform than in the prior art. Happens. Therefore, not only the more vigorous and uniform mixing but also the heating is made uniform, the positive electrode active material precursor is formed into small and uniform particles, and the reaction is also vigorously and uniformly progressed, so that a final yield can be obtained in a high yield within a short time.

For example, a metal salt aqueous solution containing 1M cobalt sulfate (CoSO4), 1M nickel sulfate (NiSO4), and 1M manganese sulfate (MnSO4) through three inflow ports (61a, 61b, 61c) at a flow rate of 4 ml / min, At a flow rate of 4 ml / min of sodium hydroxide at 6 M, 28 to 30% of ammonia aqueous solution was introduced at 0.4 ml / min, respectively, and then the inner rotary elliptical cylinder 53 was rotated at 700 rpm under a condition of 45 ° C. and pH 11 above. The aqueous solutions are reacted and crystallized to prepare MnNiCo (OH) 2, and in consideration of the average residence time, one of the plurality of outlet ports 62a, 62b, and 62c is selected to obtain a precursor.

Meanwhile, as shown in FIG. 9, a plurality of metal salt inlet ports 61a through which the metal salt aqueous solution A1 is input are provided, and the metal salt aqueous solutions A1, A1 ', and A1 "having different compositions for each metal salt inlet port 61a are introduced. If possible, it is possible to obtain particles in the form of core-shell, wherein each metal salt inlet port 61a may be arranged in series in the longitudinal direction in the fluid passage 52, as shown in FIG. 8. It may be arranged in parallel, as shown in Fig. 9. A case where A1 is Co: Ni: Mn = 0: 1: 1 and A1 'is Co: Ni: Mn = 1: 1: 1 :, where A1 "is Co: Ni: Mn = 1: 0: 1, the particles produced have a core cell structure having the composition of A1, A1 ', A1" from the inside to the outside. The usefulness of the core cell structure is well disclosed in Korean Patent Nos. 667487 and 738192. Each gold as shown in Fig. 8. If the salt inlet port (61a) which is arranged in parallel on the same starting line there will be an inflow with a time difference A1, A1 ', A1 ".

In the case where a plurality of metal salt inflow ports 61a are installed as shown in FIG. 9, when the aqueous metal salt solutions A1, A1 ', and A1 "are introduced, the basic aqueous solution A2 must also be introduced. It is preferable that a plurality of basic aqueous solution inlet ports 61b are installed to correspond to the above, when considering the reaction, the corresponding metal salt inlet ports 61a and the basic aqueous solution inlet ports 61b are disposed to face each other. desirable.

On the other hand, as shown in FIG. 10, the product coming out of any one of the outlet ports 62a, 62b, 62c may be returned to the return inlet port 61d. In this case, the shell having the reverse composition is again covered with the particles already formed in the core cell form. By properly setting the position of the return inlet port 61d, the shell having various compositions can be arranged in the core cell particles.

On the other hand, as shown in Figure 11 a plurality of inlet ports (61a, 61b, 61c) are arranged in series in the longitudinal axis and the injection port of the metal salt aqueous solution (A1), basic aqueous solution (A2), and ammonia aqueous solution (A3), respectively By selecting one by one, the injection positions of the aqueous metal salt solution (A1), the basic aqueous solution (A2) and the aqueous ammonia solution (A3) can be differentiated. This is a matter of selecting appropriately depending on which raw materials are used specifically.

12 is a view for explaining the protruding screw 64, the spiral protruding screw 64 protruding in a screw shape is installed on any one of the inner surface of the outer fixed cylinder (51) and the outer surface of the inner rotary elliptical cylinder (53). Can be. When the spiral protruding screw 64 is installed, the flow of the screw type vortex 65 is further generated without significantly disturbing the flow of the vortex, so that the fluctuation of the vortex becomes more uniform and larger, thereby making the active material having a smaller and uniform particle size. A precursor can be obtained.

[Example 2]

13 and 14 are views for explaining a method of manufacturing a cathode active material precursor for a lithium secondary battery according to a second embodiment, Figure 13 is an improved Kuet-Taylor vortex reactor used in the second embodiment of the present invention It is a schematic diagram and FIG. 14 is a graph for demonstrating the change of the linear velocity v according to a longitudinal axis direction.

14 and 14, the vortex reaction device used in the second embodiment of the present invention includes an external inclined fixing cylinder 51 and an internal inclined rotating cylinder 53 rotating therein, and inside The inclined rotating cylinder 53 has a rotating shaft 54 coincident with the longitudinal axis of the outer inclined fixing cylinder 51.

Since the side walls of the inner inclined rotating cylinder 53 and the external fixed rotating cylinder 51 are inclined at the same inclination, the distance d between the inner inclined rotating cylinder 53 and the outer rotating fixed cylinder 51 is the rotation shaft 54. Is constant along. Since the large diameter portion L and the small diameter portion S of the internal inclined rotation cylinder 53 rotate at the same angular velocity ω, the large diameter portion L is larger than the small diameter portion S as shown in FIG. It has a linear velocity (v).

Larger linear velocities (v) result in more active Kuet-Taylor vortices, resulting in uniform mixing, uniform reactions, uniform nucleation, and large shear in the fluid passages (52) of the larger diameter (L) than the smaller diameter (S). Particle breakage due to stress occurs more actively.

On the other hand, in the small diameter portion (S), since the linear velocity (v) is relatively slow, aggregation and nucleation growth are good, and particle breakage is less, so in the small diameter portion (S) It is advantageous to make large particles, and to make small particles in large diameter portion (L).

According to the present invention, since the linear velocity of the internal inclined rotation cylinder 53 changes constantly along the flow direction of the fluid when the internal inclined rotation cylinder 53 rotates, that is, the variation of the linear velocity according to the flow direction of the fluid, that is, the inclined cylinder Considering the inclination of (52, 53) it is possible to vary the process recipe (recipe).

The inlet ports 61a, 61b, 61c, the outlet ports 62a, 62b, 62c, the temperature regulating means 51a and the protruding screw 64 in Fig. 12 in Figs. The same applies. Since the interval between the inner inclined rotating cylinder 53 and the outer inclined fixing cylinder 51 is constant along the longitudinal axis, the temperature adjusting means 51a contributes uniformly along the fluid passage 52.

Since the linear velocity of the internal inclined rotary cylinder 53 decreases uniformly from the inflow ports 61a, 61b, and 61c to the outflow ports 62a, 62b, and 62c, the product B on the inflow ports 61a, 61b, and 61c. ) Nucleation occurs a lot and the growth of the product (B) occurs actively toward the outlet ports (62a, 62b, 62c). Therefore, even through a short length of reactor, it is possible to obtain a positive electrode active material precursor having small and uniform particles in the reactor.

According to the process recipe (recipe) by changing the position of the inlet port (61a, 61b, 61c) and the outlet port (62a, 62b, 62c) may be made to reverse the situation can cope with various situations.

51a: temperature control means
61a, 61b, 61c: inlet port
61d: return inlet port
62a, 62b, 62c: outlet port
64: protruding screw
151, 51: outer cylinder
153, 53: inner barrel
154, 54: axis of rotation
152, 52: fluid passage
155: vortex

Claims (17)

Consisting of the outer cylinder and inner cylinder sharing the longitudinal axis together, the outer cylinder and the inner cylinder has an empty double cylinder structure to form a fluid passage, one of the outer cylinder and the inner cylinder has a circular cross section perpendicular to the longitudinal axis The other is a cross-section perpendicular to the longitudinal axis of the elliptical shape, the fluid flows in the vortex flow in the fluid passage through the relative rotational movement of the outer cylinder and the inner cylinder made of the longitudinal axis as the rotation axis, the outer cylinder An inlet port communicating with the fluid passage is provided at a front end portion of the outer passage, and an outlet port communicating with the fluid passage is provided at a rear end portion of the outer passage, and the inner passage or the outer passage is configured to control the temperature of the fluid passage. To prepare a positive electrode active material precursor using a vortex reactor equipped with a temperature control means,
A first step of mixing and reacting in the fluid passage by introducing a metal salt aqueous solution, a basic aqueous solution, and an aqueous ammonia solution as a source material into the inflow port; And
A second step of obtaining discharge of the positive electrode active material precursor which is a result of the reaction in the fluid passage to the outlet port; Method for producing a cathode active material precursor for a lithium secondary battery comprising a. It consists of an outer cylinder and an inner cylinder sharing the longitudinal axis, but the outer cylinder and the inner cylinder has an empty double cylinder structure to form a fluid passage, and the outer cylinder and the inner cylinder so that the outer cylinder and the inner cylinder are spaced apart from each other at regular intervals along the longitudinal axis The side wall of the inclined at the same slope, the fluid flows in the vortex form in the fluid passage through the relative rotational movement of the outer passage and the inner passage made of the axis of rotation, the front end of the outer passage the fluid passage An inflow port communicating with the inflow port is provided, and an outflow port communicating with the fluid passage is provided at a rear end of the outer cylinder, and a vortex reaction having a temperature control means for controlling the temperature of the fluid passage in the inner cylinder or the outer cylinder; Using the device to prepare a positive electrode active material precursor,
A first step of mixing and reacting in the fluid passage by introducing a metal salt aqueous solution, a basic aqueous solution, and an aqueous ammonia solution as a source material into the inflow port; And
A second step of obtaining discharge of the positive electrode active material precursor which is a result of the reaction in the fluid passage to the outlet port; Method for producing a cathode active material precursor for a lithium secondary battery comprising a. The method of claim 1 or 2, wherein the aqueous metal salt solution is cobalt (Co), Mn (manganese), nickel (Ni), aluminum (Al), cobalt (Co), manganese (Mn), aluminum (Al), magnesium (Mg), copper (Cu), zinc (Zn), iron (Fe), vanadium (V), chromium (Cr), titanium (Ti), tungsten (W) and molybdenum (Mo) Method for producing a positive electrode active material precursor for a lithium secondary battery, characterized in that the metal salt containing the above metal is an aqueous metal salt solution dissolved in water at a concentration of 0.5M to 4M. 4. The method of claim 3, wherein the metal salt is sulfate, nitrate, acetate, chloride, or phosphate. 5. The method of claim 1 or 2, wherein the basic aqueous solution is a 1 M to 8 M sodium hydroxide solution or an aqueous potassium hydroxide solution. The method of claim 1 or 2, wherein the aqueous ammonia solution is 15 to 30% aqueous ammonia and is introduced at 1 to 20% by volume based on the entire source material. According to claim 1 or 2, wherein the relative rotational movement of the outer cylinder and the inner cylinder in the first step is made by the outer cylinder is fixed and the inner cylinder is rotated at 10 ~ 5000rpm, Mixing and reaction is a method for producing a cathode active material precursor for a lithium secondary battery, characterized in that the fluid passage is 30 ~ 60 ℃, pH 10 ~ 12 conditions. The method of claim 1 or 2, wherein the outlet port is provided in plural numbers so as to be arranged in series in the longitudinal axis direction. The method of claim 1, wherein a plurality of inflow ports are provided, and the metal salt aqueous solution, the basic aqueous solution, and the ammonia aqueous solution are introduced into each inlet port independently. The aqueous metal salt solution, the basic aqueous solution and the aqueous ammonia solution are disposed in a plurality of inlet ports so as to be arranged in series in the longitudinal axis direction, and the aqueous solution of the metal salt, the basic aqueous solution and the aqueous ammonia solution are disposed relatively later. The inflow port is located in the positive electrode active material precursor manufacturing method for a lithium secondary battery, characterized in that it serves as a return port to return to the inlet port located relatively ahead. The method of manufacturing a cathode active material precursor for a lithium secondary battery according to claim 1 or 2, wherein a spiral protruding screw protruding in a screw shape is provided at any one of an inner surface of the inner cylinder and an outer surface of the outer cylinder. According to claim 1 or claim 2, wherein the inlet port comprises a plurality of metal salt inlet port for injecting the aqueous metal salt solution, through each of the metal salt inlet port is characterized in that the metal salt aqueous solution having a different composition of the metal salt is introduced Method for producing a positive electrode active material precursor for a lithium secondary battery. The method of claim 12, wherein the inlet port is a metal salt inlet port for injecting the aqueous metal salt solution, the basic aqueous solution inlet port for injecting the basic aqueous solution, and the ammonia aqueous solution inlet port for injecting the aqueous ammonia solution are respectively installed independently Method for producing a positive electrode active material precursor for a lithium secondary battery. The method of claim 13, wherein the basic aqueous solution inlet port is provided in plural numbers so as to correspond to each of the metal salt inlet ports. 15. The method of claim 14, wherein the basic aqueous solution inlet port and the metal salt inlet port are installed so that corresponding ones face each other. The positive electrode for a lithium secondary battery according to claim 1 or 2, wherein a return inlet port is provided at a front end of the outer cylinder and the reaction product coming out through the outlet port is returned to the return inlet port. Active material precursor manufacturing method. The method of claim 16, wherein a plurality of outlet ports are provided, a part of which is used to return the reaction product to the inlet for return.

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