Cathode active material precursor manufacturing apparatus and manufacturing method

Abstract

The method for producing a positive electrode active material precursor according to the present invention comprises a reaction vessel; one or more input pipes for introducing a reaction solution into the reaction vessel; and a stirring means located on the central side inside the reaction vessel for stirring the reaction solution introduced from the input pipes; wherein the stirring means comprises a shaft and a two-stage impeller, and the impeller has an angle of 5 to 90° with respect to the horizontal direction.

Description

Technical Field

[0006] , , ,

[0001] The present invention relates to a device and a method for manufacturing a positive electrode active material precursor.

Background Art

[0002] As the demand for mobile devices such as smartphones and notebook computers increases and the markets for hybrid cars and electric vehicles grow, the demand for secondary batteries as an energy source has been rapidly increasing. In particular, lithium secondary batteries that exhibit high energy density, operating potential, long cycle life, and low self-discharge rate are widely used.

[0003] To manufacture the positive electrode active material of a lithium secondary battery, a lithium source, a positive electrode active material precursor, a dopant, etc. are required. Among these, as a method for manufacturing the positive electrode active material precursor, instead of the existing solid-phase reaction method, a coprecipitation method is often used in which chlorides, nitrides, sulfides, etc. containing raw materials are precipitated with hydroxides in a basic solution and grown to a particle size. [[ID=​​​​​​​​​​​​​​​​​​​​

[0007] The present invention provides a positive electrode active material precursor manufacturing apparatus comprising: a reaction vessel; one or more input pipes for introducing a reaction solution into the reaction vessel; and a stirring means located on the central side inside the reaction vessel for stirring the reaction solution introduced from the input pipes; wherein the stirring means comprises a shaft and a two-stage impeller, the impeller having an angle of 5 to 90° with respect to the horizontal direction.

[0008] Furthermore, the present invention provides a method for producing a positive electrode active material precursor, comprising the steps of: introducing an initial solution into a reaction vessel; introducing a reaction solution into the reaction vessel containing the initial solution; and stirring the initial solution and the reaction solution with a stirring means to obtain a positive electrode active material precursor, wherein the stirring means includes a shaft and a two-stage impeller, the impeller having an angle of 5 to 90° with respect to the horizontal direction, and the initial solution is introduced so as to completely immerse the two-stage impeller. [Effects of the Invention]

[0009] The cathode active material precursor manufacturing apparatus and manufacturing method according to the present invention have the advantage of suppressing the formation of fine powder and improving the growth uniformity and sphericity of the cathode active material precursor. Furthermore, by improving the deviation of internal concentration, impurities can be controlled and the accuracy of the composition can be improved. [Brief explanation of the drawing]

[0010] [Figure 1] This drawing illustrates a manufacturing apparatus for a positive electrode active material precursor according to several embodiments of the present invention. [Figure 2] This drawing illustrates a manufacturing apparatus for a positive electrode active material precursor according to several embodiments of the present invention. [Figure 3] This drawing shows a side view of a stirring means according to several embodiments of the present invention. [Figure 4] This is a plan view showing a positive electrode active material precursor manufacturing apparatus according to several embodiments of the present invention. [Figure 5]This figure shows SEM images of cathode active material precursors produced according to the examples and comparative examples. [Figure 6] This figure shows SEM images of cathode active material precursors produced according to the examples and comparative examples. [Figure 7] This diagram shows the supernatant liquid observed for measuring the unreacted Ni of the positive electrode active material precursor produced by the examples and comparative examples. [Figure 8] This diagram shows the supernatant liquid observed for measuring the unreacted Ni of the positive electrode active material precursor produced by the examples and comparative examples. [Modes for carrying out the invention]

[0011] Embodiments of the present invention will be described in detail below. However, these are presented as examples only and the present invention is not limited thereto, and is defined solely within the scope of the claims described later.

[0012] In this invention, when one member is said to be "on top of" another member, this includes not only cases where one member is in direct contact with another member, but also cases where another member is interposed between the two members.

[0013] In the present invention, when a part is said to "include" a certain component, this means that, unless otherwise stated, it may include other components rather than excluding them.

[0014] <Manufacturing equipment for positive electrode active material precursors> One embodiment of the present invention relates to a positive electrode active material precursor manufacturing apparatus 100, comprising: a reaction vessel 10; one or more input pipes 20, 30, 40 for introducing a reaction solution into the reaction vessel 10; and a stirring means 60 located on the central side inside the reaction vessel 10 for stirring the reaction solution introduced from the input pipes 20, 30, 40; wherein the stirring means 60 comprises a shaft 61 and two stages of impellers 62, 63, the impellers 62, 63 having an angle of 5 to 90° with respect to the horizontal direction.

[0015] The positive electrode active material precursor manufacturing apparatus 100 according to the present invention can control the formation of fine powder by suppressing the scattering of the reaction solution using two-stage impellers sixth and 63. Therefore, there is an advantage that the growth uniformity and sphericity of the positive electrode active material precursor can be improved.

[0016] The positive electrode active material precursor manufacturing apparatus 100 according to the present invention can be a coprecipitation reaction apparatus for manufacturing a catalyst or a positive electrode active material precursor for a lithium secondary battery, including a continuous stirred tank reactor (CSTR) based on a batch reactor.

[0017] FIG. 1 schematically shows the positive electrode active material precursor manufacturing apparatus 100 according to some embodiments of the present invention.

[0018] The positive electrode active material precursor manufacturing apparatus 100 according to the present invention includes a reaction vessel 10. The reaction vessel 10 can be formed in a cylindrical shape into which a reaction solution is introduced and the upper end is open. Alternatively, although not shown, the reaction vessel 10 may be in the form of a structure in which a central cylindrical main body, a bottom, and an upper lid portion are assembled through a flange structure, but is not limited thereto.

[0019] The reaction vessel 10 accommodates the reaction solution therein and causes a reaction. The reaction vessel 10 can include, but is not limited to, a drain portion for discharging the generated positive electrode active material precursor to the outside.

[0020] The positive electrode active material precursor manufacturing apparatus 100 according to the present invention includes one or more input pipes 20, 30, 40 for introducing a reaction solution into the reaction vessel 10.

[0021] In one embodiment of the present invention, the input pipes 20, 30, 40 can include a first input pipe 20 for introducing a first solution containing NH4OH, a second input pipe 30 for introducing a second solution containing NaOH, and a third input pipe 40 for introducing a metal solution.

[0022] The input pipes 20, 30, and 40, although not shown in the figures, can be connected to their respective storage tanks where the reaction solution is stored.

[0023] The aforementioned input pipes 20, 30, and 40 may, but are not limited to, be equipped with flow rate measuring devices.

[0024] The material of the input pipes 20, 30, and 40 is not limited as long as it has corrosion resistance and chemical resistance to the first solution, the second solution, and the metal solution. The material of the input pipes 20, 30, and 40 can be, for example, at least one of the following materials: stainless steel, PP, PVC, PE, and PVDF.

[0025] The diameters and thicknesses of the input pipes 20, 30, and 40 can be appropriately changed and designed according to the capacity of the reaction vessel 10.

[0026] For example, in the case of the reaction vessel 10 having a volume of 10 to 30 tons, the input pipes 20, 30, and 40 may have a diameter of 5 to 80 mm, preferably 10 to 65 mm, and more preferably 15 to 50 mm, but are not limited to this. It is preferable that the diameters of the input pipes 20, 30, and 40 are within the above range because it facilitates the input of the first solution, the second solution, and the metal solution.

[0027] For example, in the case of the reaction vessel 10 having a volume of 10 to 30 tons, the input pipes 20, 30, and 40 may have a thickness of 1 to 15 mm, preferably 1.5 to 10 mm, and more preferably 2 to 5 mm, but are not limited to this. It is preferable that the thickness of the input pipes 20, 30, and 40 meets the above range because it provides excellent durability.

[0028] In yet another embodiment of the present invention, the first input pipe 20 and the third input pipe 40 may be arranged adjacent to each other.

[0029] Specifically, when the first input pipe 20 and the third input pipe 40 are arranged adjacent to each other, it is advantageous for the formation of a complex compound between the metal solution introduced through the third input pipe 40 and the NH4OH of the first solution introduced through the first input pipe 20, allowing the reaction rate to be controlled and thus promoting uniform growth. More specifically, when the metal solution and the NH4OH of the first solution react, a complex compound is formed, which then reacts with the NaOH of the second solution to carry out a coprecipitation reaction. Therefore, by arranging the first input pipe 20 and the third input pipe 40 adjacent to each other, a fast reaction rate can be controlled. In addition, the formation of aggregates that induce clogging at the ends of the input pipes 20 and 40 can be suppressed.

[0030] In yet another embodiment of the present invention, the input pipes 20, 30, and 40 may be branched into 3 to 4 branches from the branching point. Specifically, referring to Figure 2, the input pipes 20, 30, and 40 may be branched into 3 branches from the branching point.

[0031] It is preferable that the input pipes 20, 30, and 40 are branched into 3 to 4 branches from the branching point, as this can improve the internal diffusivity of the reaction solution.

[0032] Specifically, when the input pipes 20, 30, and 40 are branched, the internal diffusivity of the reaction solution is improved, which has the advantage of inducing uniform particle growth, controlling impurities, and improving the accuracy of the composition. It is also preferable because it can improve the concentration deviation within the reaction solution.

[0033] Figure 4 is a diagram illustrating a plan view of a positive electrode active material precursor manufacturing apparatus 100 according to several embodiments of the present invention. Referring to Figure 4, the first input pipe 20 and the third input pipe 40 may branch into 3 to 4 branches from a branching point, in which case the branch pipes of the first input pipe 20 may be arranged adjacent to the branch pipes of the third input pipe 40. When the input pipes 20 and 40 are branched, it is preferable that the distance between adjacent branch pipes is the same. For example, if the first input pipe 20 is branched into a 3-branch pipe, the 3-branch pipes may be branched so that they are at the same distance from each other.

[0034] Referring to Figure 4, in the case of the first inlet pipe 20 and the third inlet pipe 40, the angle θ2 formed by the line extending from the first branch pipe to the shaft 61, which is the central axis of the impellers 62 and 63 (described later), and the line extending from the last branch pipe to the shaft 61, can be within 135°, preferably 90° to 135°. In the case of the second inlet pipe 30, the angle θ3 formed by the line extending from the first branch pipe to the shaft 61 and the line extending from the last branch pipe to the shaft 61 can be within 120°, preferably 60° to 120°. Preferably, each of the branch pipes can be arranged at the same interval within the angles within the above ranges.

[0035] When θ2 and θ3 satisfy the above range, the solution in the input pipes 20, 30, and 40 can diffuse uniformly within the reaction solution, improving the internal concentration deviation, which is preferable because it can suppress non-uniform particle growth and impurities.

[0036] Specifically, it is preferable that the first input pipe 20 into which the first solution containing NH4OH is introduced and the third input pipe 40 into which the metal solution is introduced are arranged adjacent to each other, because this can suppress the phenomenon of aggregate formation at the end of the third input pipe 40.

[0037] The second input pipe 30 into which the second solution containing NaOH is introduced may be located on the opposite side of the first input pipe 20 and the third input pipe 40.

[0038] Generally, when a metal solution is added to a reaction solution within the pH range of 10-13, precipitation occurs immediately. However, if the amount of metal added relative to the solution time increases, precipitation occurs without uniform diffusion of ions such as metal ions, sodium, and sulfate ions. For this reason, a concentration deviation occurs within the reaction solution, leading to a problem where the concentration of unreacted metals, Na, S ions, and other impurities increases within the synthesized cathode active material precursor. In particular, if unreacted metals are induced, the overall process loss increases, resulting in higher processing costs.

[0039] When the second input pipe 30 is located on the opposite side of the first input pipe 20 and the third input pipe 40, specifically when the centers of θ2 and θ3 are positioned such that they satisfy 180° with respect to the shaft 61, it is preferable because the metal ions form complex compounds, making it easy to control the reaction rate and suppressing the aforementioned problems.

[0040] The diameters of the branch pipes may all be the same or different. It is preferable that the diameters of each inlet pipe 20, 30, and 40 after they have been branched are the same. When the diameters after branching are all the same, it is preferable because it helps in flow rate control in the branched pipes. Specifically, when the first inlet pipe 20 includes branch pipes that have been branched into three, it is preferable that the diameters of the branch pipes are all the same. Also, referring to Figure 2, it is preferable that the diameters of the inlet pipes 20, 30, and 40 before branching are larger than or the same as the diameters of the branch pipes after they have been branched.

[0041] The branching points may, but are not limited to, be located at a distance of 1 / 20 to 1 / 5, preferably 1 / 10 to 1 / 7, from the upper ends of the input pipes 20, 30, and 40.

[0042] In yet another embodiment of the present invention, the input pipes 20, 30, and 40 may further include deionized water (DI water) input pipes and nitrogen input pipes 50.

[0043] The deionized water input pipe may be provided for introducing deionized water contained in the initial solution, which will be described later. Since the deionized water introduced through the deionized water input pipe does not need to be introduced during the manufacturing process of the positive electrode active material precursor, the location of the deionized water input pipe is not particularly limited.

[0044] The nitrogen input pipe 50 may be provided for nitrogen purging to remove dissolved oxygen from the initial solution and to create a non-oxidizing atmosphere inside the reaction vessel 10. Referring to Figure 4, the nitrogen input pipe 50 may, but is not limited to, be provided relatively close to the first input pipe 20.

[0045] The ends of the input pipes 20, 30, and 40 may be positioned at a point 1 / 20 to 2 / 5 of the way from the bottom of the reaction vessel 10, preferably 1 / 10 to 1 / 7 of the way from the bottom. When the ends of the input pipes 20, 30, and 40 are located within this range, the spacing and arrangement with the stirring means 60, which will be described later, are appropriate, making stirring easy and allowing for uniform diffusion by the vortex flow, which is preferable.

[0046] Preferably, the ends of the input pipes 20, 30, and 40 are located at the same point from the bottom of the reaction vessel 10 (see Figure 2).

[0047] The cathode active material precursor manufacturing apparatus 100 according to the present invention includes a stirring means 60 located on the central side inside the reaction vessel 10 for stirring the reaction solution introduced from the input pipes 20, 30, and 40, wherein the stirring means 60 includes a shaft 61 and two stages of impellers 62 and 63, the impellers 62 and 63 having an angle of 5 to 90° with respect to the horizontal direction.

[0048] Conventional mass-production reactors increase the input volume of the reaction solution for large-scale synthesis and stir the solution by setting the spacing between three or more multi-stage impellers relative to the simple volume. In this case, as the reaction units become larger, uniformity is inhibited, fine powder is formed, and it becomes very difficult to produce a precursor with a uniform form.

[0049] Furthermore, as the water level of the reaction solution rises during the reaction, the reaction solution is scattered each time it comes into contact with the impeller. While the scattered reaction solution remains on the wall, it cannot receive a supply of reaction raw materials such as metal ions, NaOH, and NH4OH, which inhibits the particle growth of the positive electrode active material precursor and induces non-uniform growth. Consequently, some problems arise where fine powder is formed, hindering particle uniformity and sphericity.

[0050] However, the present invention has the advantage that by utilizing two-stage impellers 62 and 63, the formation of fine powder can be controlled by suppressing the scattering of the reaction solution, thereby improving the uniformity of growth and sphericity.

[0051] The impellers 62 and 63 according to the present invention have an angle of 5 to 90° with respect to the horizontal direction.

[0052] Figure 3 shows a side view of a stirring means 60 according to several embodiments of the present invention.

[0053] Specifically, referring to Figure 3, the impellers 62 and 63 may be installed at an angle such that θ1, defined with respect to the horizontal direction, is 5 to 90°, preferably 15 to 70°, and more preferably 30 to 45°. In short, the impellers 62 and 63 may be configured such that the angle of the blades is inclined from the upper left end to the lower right end at 5 to 90°.

[0054] By arranging the impellers 62 and 63 to have angles within the aforementioned range, a vortex can be formed from the lower end to the upper end of the reaction vessel 10. In this case, the rotation direction of the impellers 62 and 63 may be clockwise.

[0055] Because the impellers 62 and 63 form the vortex, the diffusion of ions in the reaction solution proceeds smoothly, eliminating concentration deviations. This has the advantage that the growth of the positive electrode active material precursor can be carried out uniformly.

[0056] In yet another embodiment of the present invention, the two-stage impellers 62, 63 may be arranged such that the vertical center of the lower stage impeller 63, located in the lower stage, is positioned at a point 1 / 15 to 1 / 5 of the way from the bottom of the reaction vessel 10, preferably at a point 1 / 8 to 1 / 6 of the way from the bottom.

[0057] In yet another embodiment of the present invention, the two-stage impellers 62, 63 may be arranged such that the vertical center of the upper stage impeller 62, located in the upper stage, is positioned at a point 1 / 4 to 1 / 2 of the way from the bottom of the reaction vessel 10, preferably 1 / 4 to 1 / 3 of the way from the bottom of the reaction vessel 10 in the vertical direction.

[0058] Specifically, the positions of the upper impeller 62 and the lower impeller 63 may be based on the vertical center of each impeller 62 and 63.

[0059] More specifically, referring to Figure 3, the stirring means 60 may be configured such that, in a side view, the vertical center points of the upper impeller 62 and the lower impeller 63 are located at points 1 / 4 to 1 / 2 and 1 / 15 to 1 / 5 of the way from the bottom of the reaction vessel 10, respectively, in the vertical direction.

[0060] When the upper impeller 62 and the lower impeller 63 are positioned to each satisfy the aforementioned range, the flow of the vortex formed by stirring is optimized, resulting in superior uniformity and sphericity of the manufactured positive electrode active material precursor, which is therefore preferable.

[0061] The diameters of the impellers 62 and 63 can be appropriately changed and designed according to the capacity of the reaction vessel 10. For example, in the case of the reaction vessel 10 having a volume of 3 to 30 tons, the diameters of the impellers 62 and 63 may be 400 to 1550 mm, preferably 700 to 1200 mm, and more preferably 800 to 1050 mm. When the diameters of the impellers 62 and 63 meet the above range, it is preferable because it is possible to produce a positive electrode active material precursor with uniform particle size and excellent sphericity while minimizing the number of impellers 62 and 63.

[0062] The upper impeller 62 and the lower impeller 63 may have different diameters or the same diameter. From the perspective of optimizing the vortex flow, it is preferable that the upper impeller 62 and the lower impeller 63 have the same diameter.

[0063] In yet another embodiment of the present invention, the two-stage impellers 62 and 63 may have the same angle with respect to the horizontal. In short, referring to Figure 3, the upper impeller 62 and the lower impeller 63 may be inclined to have the same angle with respect to the horizontal. When the upper impeller 62 and the lower impeller 63 have the same angle with respect to the horizontal, it is preferable because the formation of vortices in the reaction solution is optimized, the ions inside the reaction solution diffuse uniformly, and a positive electrode active material precursor with excellent uniformity and sphericity can be obtained.

[0064] The cathode active material precursor manufacturing apparatus 100 according to the present invention may further include, but is not shown in the figures, known pumps, heaters, coolers, drain lines, etc., as long as they do not hinder the objectives of the present invention. For example, the reaction vessel 10 may be provided with a drain line at the bottom for recovering the manufactured cathode active material precursor, and the outer edge of the reaction vessel 10 may be further provided with heaters and coolers for controlling the temperature of the solution inside the reaction vessel 10, and the upper or lower side of the reaction vessel 10 may be further provided with a sensing tank, etc., which uses a circulation pump to discharge and circulate the solution in the reaction vessel 10, but is not limited thereto. The drain line may also be connected to a filtration device, but is not limited thereto.

[0065] The cathode active material precursor manufacturing apparatus 100 according to the present invention has the advantage of being able to produce cathode active material precursors with excellent uniformity and sphericity and minimal impurities without the use of additional additives. In particular, it has the advantage of being able to easily obtain the desired cathode active material precursor regardless of its composition.

[0066] <Cathode active material precursor manufacturing method> Another aspect of the present invention relates to a method for producing a positive electrode active material precursor, comprising the steps of: introducing an initial solution into a reaction vessel 10; introducing a reaction solution into the reaction vessel 10 containing the initial solution; and stirring the initial solution and the reaction solution with a stirring means 60 to obtain a positive electrode active material precursor, wherein the stirring means 60 includes a shaft 61 and two stages of impellers 62, 63, the impellers 62, 63 having an angle of 5 to 90° with respect to the horizontal direction, and the initial solution being introduced so as to completely immerse the two stages of impellers 62, 63.

[0067] In short, another aspect of the present invention relates to a method for producing a positive electrode active material precursor using the positive electrode active material precursor production apparatus 100 described above.

[0068] The method for producing a cathode active material precursor according to the present invention includes the step of adding an initial solution to a reaction vessel 10.

[0069] The aforementioned reaction vessel 10, stirring means 60, and input pipes 20, 30, 40, etc., which will be described later, can be to which the above-mentioned provisions apply.

[0070] In yet another embodiment of the present invention, the initial solution may include deionized water.

[0071] The initial solution is poured in such a way that the two stages of impellers 62 and 63, in other words, the upper impeller 62 and the lower impeller 63, are completely submerged. In other words, in the method for producing a positive electrode active material precursor according to the present invention, the reaction begins with the two stages of impellers 62 and 63 completely submerged, which can suppress non-uniform diffusion within the reaction solution and suppress the scattering of the reaction solution.

[0072] Conventional multi-stage impellers with three or more stages had the problem that it was practically difficult to ensure that all of the multi-stage impellers were fully submerged. Consequently, as the water level of the reaction solution rose during the reaction, the reaction solution would splash each time it came into contact with the multi-stage impeller, which inhibited the growth of the positive electrode active material precursor particles.

[0073] However, the method for producing a positive electrode active material precursor according to the present invention has the advantage that, since the reaction starts with both stages of impellers 62 and 63 fully immersed, the scattering of the reaction solution is suppressed, and the phenomenon of the reaction solution accumulating on the walls of the reaction vessel 10 is suppressed, thereby controlling the formation of fine powder and improving the uniformity and sphericity of the growth of the positive electrode active material precursor.

[0074] The initial solution may further contain one or more substances selected from the group consisting of NH4OH and NaOH. In short, the initial solution may include a portion of the first solution containing NH4OH and a portion of the second solution containing NaOH.

[0075] The NH4OH may be present in an amount of 0 to 10% by weight, preferably 0 to 5% by weight, and more preferably 0.1 to 3% by weight, relative to the total weight of the initial solution.

[0076] The NaOH may be present in an amount of 0 to 10% by weight, preferably 0 to 5% by weight, and more preferably 0.1 to 3% by weight, relative to the total weight of the initial solution.

[0077] The deionized water may be included in a remainder such that it makes up 100% by weight of the entire initial solution.

[0078] It is preferable that the NH4OH and NaOH are each within the aforementioned ranges because the reaction effect can be further enhanced. Specifically, it is preferable that the initial particle size of the cathode active material precursor produced is appropriate and uniform when the NH4OH and NaOH are each within the aforementioned ranges.

[0079] The amount of the initial solution added is not limited as long as it is sufficient to completely immerse the two stages of impellers 62 and 63.

[0080] The method for producing a positive electrode active material precursor according to the present invention may further include a step of stirring the initial solution.

[0081] The method for producing a cathode active material precursor according to the present invention may further include, but is not limited to, a step of purging the initial solution with nitrogen (N2 purge).

[0082] The steps of stirring the initial solution and purging the initial solution with nitrogen can be performed simultaneously.

[0083] Specifically, the method for producing a positive electrode active material precursor according to the present invention may further include a step of purging the initial solution with nitrogen while stirring it.

[0084] When purging the initial solution with nitrogen while stirring, dissolved oxygen in the initial solution can be removed, and the uniformity of the manufactured positive electrode active material precursor can be improved. Therefore, it is preferable to further include the step of purging the initial solution with nitrogen while stirring.

[0085] The amount of nitrogen supplied, the supply time, etc., are not limited in this invention.

[0086] The method for producing a positive electrode active material precursor according to the present invention includes the steps of: adding a reaction solution to the reaction vessel 10 into which the initial solution has been introduced; and stirring the initial solution and the reaction solution with a stirring means 60 to obtain a positive electrode active material precursor.

[0087] In yet another embodiment of the present invention, the reaction solution may include a first solution containing NH4OH, a second solution containing NaOH, and a metal solution.

[0088] The first solution, the second solution, and the metal solution may be included in appropriate ratios depending on the composition of the positive electrode active material precursor to be manufactured. Specifically, by adjusting the flow rates of the first solution, the second solution, and the metal solution, a positive electrode active material precursor of the desired form can be obtained.

[0089] The metal solution may contain salts of one or more metals selected from the group consisting of nickel, cobalt, and manganese.

[0090] For example, the nickel (Ni) may be contained in the metal solution as Ni(OH)2, NiO, NiOOH, NiCO3·2Ni(OH)2·4H2O, NiC2O2·2H2O, Ni(NO3)2·6H2O, NiSO4, NiSO4·6H2O, fatty acid nickel salts, or nickel halides, and at least one of these can be used.

[0091] The cobalt may be contained in the metal solution as Co(OH)2, CoOOH, Co(OCOCH3)2·4H2O, Co(NO3)2·6H2O, or CoSO4·7H2O, and at least one of these can be used.

[0092] Furthermore, the manganese (Mn) in the metal solution may include manganese oxides such as Mn2O3, MnO2, and Mn3O4; manganese salts such as MnCO3, Mn(NO3)2, MnSO4, manganese acetate, manganese dicarboxylate salts, manganese citrate, and manganese fatty acid salts; oxyhydroxides, and manganese chloride, and at least one or more of these may be used.

[0093] Furthermore, the metal solution may further contain a salt of at least one metal selected from the group consisting of Al, Zr, B, W, Mo, Cr, Ta, Nb, Mg, Ce, Hf, Ta, La, Ti, Sr, Ba, Ce, F, P, S, and Y. For example, the metal solution may further contain at least one acetate, nitrate, sulfate, halogen compound, sulfide, hydroxide, oxide, or oxyhydroxide selected from the group consisting of Al, Zr, B, W, Mo, Cr, Ta, Nb, Mg, Ce, Hf, Ta, La, Ti, Sr, Ba, Ce, F, P, S, and Y.

[0094] The flow rate of the reaction solution can be appropriately varied by the input pipes 20, 30, and 40 through which the reaction solution is introduced.

[0095] In yet another embodiment of the present invention, the metal solution may be introduced at a flow rate of 80 to 3200 kg / h, preferably 104 to 2250 kg / h, and more preferably 120 to 1950 kg / h.

[0096] If the third input pipe 40 into which the metal solution is introduced is branched into three, the metal solution may be introduced into each branch pipe at a flow rate of 30 to 1000 kg / h, preferably 38 to 750 kg / h, more preferably 40 to 650 kg / h. If the third input pipe 40 is branched into four, the metal solution may be introduced into each branch pipe at a flow rate of 20 to 800 kg / h, preferably 25 to 680 kg / h, more preferably 30 to 550 kg / h.

[0097] In the case of the second solution, the flow rate can be appropriately adjusted depending on the morphology before administration.

[0098] In yet another embodiment of the present invention, the second solution may be introduced at a flow rate of 40 to 1800 kg / h, preferably 60 to 1650 kg / h, and more preferably 70 to 1330 kg / h.

[0099] If the second input pipe 30 into which the second solution is introduced is branched into three branches, the second solution can be introduced into each branch pipe at a flow rate of 15 to 550 kg / h, preferably 20 to 480 kg / h, and more preferably 22 to 430 kg / h.

[0100] If the second input pipe 30 is branched into four branches, the second solution can be introduced into each branch pipe at a flow rate of 10 to 450 kg / h, preferably 15 to 370 kg / h, and more preferably 17 to 330 kg / h.

[0101] In the case of the first solution, the flow rate can be appropriately adjusted depending on the morphology. For example, the first solution can be introduced at a flow rate of 10 to 1320 kg / h, preferably 20 to 1200 kg / h, and more preferably 24 to 690 kg / h.

[0102] If the first input pipe 20 into which the first solution is introduced is branched into three branches, the first solution can be introduced into each branch pipe at a flow rate of 5 to 400 kg / h, preferably 8 to 230 kg / h.

[0103] If the first input pipe 20 is branched into four branches, the first solution can be introduced to each branch pipe at a flow rate of 3 to 330 kg / h, preferably 5 to 180 kg / h, but is not limited thereto.

[0104] In yet another embodiment of the present invention, the molar ratio of metal ions in the metal solution to NH4OH may be 1:0.2 to 1:0.9, preferably 1:0.2 to 1:0.7. When the molar ratio of metal to NH4OH in the metal solution satisfies the above range, it is preferable because it can suppress the induction of unreacted transition metals.

[0105] In yet another embodiment of the present invention, the molar ratio of metal ions in the metal solution to NaOH may be 1:1.5 to 1:2.5, preferably 1:1.8 to 1:2.3, and more preferably 1:1.94 to 1:2.05. When the molar ratio of metal to NaOH in the metal solution satisfies the above range, it is preferable because it can suppress the induction of unreacted transition metals.

[0106] If the initial solution contains NH4OH and / or NaOH, the first solution containing NH4OH and the second solution containing NaOH may each be included in such a way that they satisfy the molar ratio with respect to the metal in the metal solution.

[0107] The method for producing a positive electrode active material precursor according to the present invention has the advantage of improving process losses due to unreacted metals because the concentration deviation of the reaction solution is suppressed during the reaction, making it easy to add the first and second solutions in the appropriate ratio. Furthermore, it can induce uniform diffusion and improve the compositional accuracy of the produced positive electrode active material precursor.

[0108] In yet another embodiment of the present invention, the steps of adding the reaction solution and stirring the initial solution and the reaction solution with the stirring means 60 to obtain a positive electrode active material precursor may be performed simultaneously.

[0109] In short, the method for producing a positive electrode active material precursor according to the present invention allows for obtaining a positive electrode active material precursor by stirring the initial solution and the reaction solution with the stirring means 60 while adding the reaction solution.

[0110] The stirring speed of the stirring means 60 is not limited in this invention. For example, the initial solution and the reaction solution can be stirred at 30 to 1500 rpm, preferably 50 to 1200 rpm, and more preferably 60 to 800 rpm.

[0111] The positive electrode active material precursor can be recovered through the drain line provided at the bottom of the reaction vessel 10 and further subjected to steps such as filtration, washing, and drying. The recovery, filtration, washing, and drying can be carried out by conventional methods and are not limited thereto in this invention.

[0112] The method for producing a positive electrode active material precursor according to the present invention has the advantage of being able to suppress unreacted substances, and the positive electrode active material precursor produced by the method for producing a positive electrode active material precursor according to the present invention has the advantage of excellent uniformity and sphericity, and low impurity content.

[0113] In yet another embodiment of the present invention, the positive electrode active material precursor may have a Na content of 550 ppm or less, specifically 300 ppm or less, more specifically 100 ppm or less, and most specifically 52 ppm or less.

[0114] In yet another embodiment of the present invention, the positive electrode active material precursor may have an S content of 5000 ppm, specifically 3500 ppm or less, and more specifically 1590 ppm or less. [Examples]

[0115] The following describes preferred embodiments and comparative examples of the present invention. However, the following embodiments are merely preferred embodiments of the present invention, and the present invention is not limited to these embodiments.

[0116] (Examples) As the initial solution, deionized water, NaOH, and NH4OH were added to a reaction vessel equipped with a two-stage impeller and a stirring device located in the center of the vessel, ensuring that both stages of the impeller were fully submerged. At this time, 1.5% by weight of NaOH, 1.5% by weight of NH4OH, and the remaining deionized water were added to the initial solution (100% by weight) and stirred. Both stages of the impeller were angled 45° with respect to the horizontal direction, with the vertical center of the upper impeller located 1 / 3 of the way from the bottom of the reaction vessel and the vertical center of the lower impeller 63 located 1 / 6 of the way from the bottom of the reaction vessel.

[0117] Subsequently, while maintaining agitation, nitrogen was purged at a rate of 10 L / min through a nitrogen injection pipe to remove dissolved oxygen from the initial solution.

[0118] NiSO4, CoSO4, and MnSO4 were mixed in deionized water to prepare a 2.5 M concentration metal solution, with a nickel:cobalt:manganese molar ratio of 0.89:0.04:0.07.

[0119] Subsequently, while maintaining stirring, aqueous NH4OH solution, aqueous NaOH solution, and metal solution were added as reaction solutions. At this time, the piping into which the aqueous NH4OH solution, aqueous NaOH solution, and metal solution were added were all supplied using three-way branched input pipes. The aqueous NH4OH solution was added at a flow rate of 23 kg / h, the aqueous NaOH solution at a flow rate of 210 kg / h, and the metal solution at a flow rate of 400 kg / h, so that the ratio of NH4OH to the total number of metal ion moles was 1:0.6 and the ratio of NaOH was 1:1.97. Stirring was carried out at 550 rpm, and the reaction was maintained for 28 hours to obtain a cathode active material precursor using the coprecipitation method.

[0120] (Comparative example) The cathode active material precursor was manufactured in the same manner as in the example, except that a conventional cathode active material precursor manufacturing apparatus (a three-stage impeller and unbranched input piping) was used.

[0121] (Example of experiment) (1) SEM measurement results The cathode active material precursors produced by the examples and comparative examples were measured using SEM imaging, and the results are shown in Figure 5 (Examples) and Figure 6 (Comparative Examples), respectively.

[0122] (2)ICP analysis Inductively coupled plasma (ICP) analysis was performed using an Agillent ICP 720-ES to determine the impurity content of the cathode active material precursors produced in the examples and comparative examples.

[0123] 2 g of precursor powder was dissolved in 10 mL of high-purity hydrochloric acid in an Erlenmeyer flask. The flask was covered with glass and heated on a high-temperature plate to completely dissolve the precursor. After cooling to room temperature, the solution was transferred to a 100 mL volumetric flask that had been washed 3-4 times with distilled (DI) water. The volumetric flask was then filled with DI water to the 100 mL mark and then homogenized completely. 5 mL of the solution was taken with a 5 mL pipette and transferred to a 50 mL volumetric flask for secondary dilution. The volumetric flask was then filled with 10% hydrochloric acid to the 50 mL mark and then homogenized. This 50 mL solution was then used for ICP measurement, and the results are shown in Table 1 below.

[0124] [Table 1]

[0125] (3) Measurement of unreacted Ni The unreacted Ni in the cathode active material precursors prepared according to the examples and comparative examples was measured. After the coprecipitation reaction was completed, 15 g of the cathode active material precursor reaction solution was quantified and then separated into a vial. The vial was then left to stand for 1 hour to precipitate the cathode active material precursor, and the supernatant of the cathode active material precursor was obtained. Approximately 5 g of the cathode active material precursor supernatant was analyzed by inductively coupled plasma (ICP) analysis using an Agillent ICP 720-ES. The results are shown in Table 2 below. Figures 7 and 8 are diagrams showing the supernatants of the cathode active material precursors prepared according to the examples and comparative examples, respectively.

[0126] [Table 2]

[0127] Referring to Figures 5-8 and Tables 1 and 2, it can be seen that the cathode active material precursors produced by the examples exhibit excellent uniformity and sphericity, and contain few unreacted metals and impurities. Specifically, referring to Figures 7 and 8, when nickel ions and ammonia form a coordinate bond, the solution turns green. In Figure 8, however, the supernatant appears concentrated, indicating that a large amount of unreacted transition metals remain.

[0128] The present invention is not limited to the embodiments described above, and can be manufactured in a variety of different forms. Those with ordinary skill in the art to which the invention pertains should understand that it can be implemented in other specific forms without altering the technical idea or essential features of the invention. Therefore, it should be understood that the embodiments described above are illustrative and not limiting in all respects. [Explanation of Symbols]

[0129] 10: Reaction vessel 20: 1st input pipe 30:Second input pipe 40: 3rd input pipe 50: Nitrogen injection piping 60: Stirring means 61: Shaft 62: Upper impeller 63: Lower impeller 100: Positive electrode active material precursor manufacturing equipment

Claims

1. reaction vessel; One or more input pipes for introducing the reaction solution into the reaction vessel; and Includes a stirring means located on the central side inside the reaction vessel for stirring the reaction solution introduced from the input pipe; The stirring means includes a shaft and a two-stage impeller. The impeller has an angle of 5 to 90° with respect to the horizontal direction. Positive electrode active material precursor manufacturing equipment.

2. The aforementioned two-stage impeller is The cathode active material precursor manufacturing apparatus according to claim 1, wherein the vertical center of the lower impeller located in the lower section is located at a point 1 / 15 to 1 / 5 of the way from the bottom of the reaction vessel.

3. The aforementioned two-stage impeller is The cathode active material precursor manufacturing apparatus according to claim 1, wherein the vertical center of the upper impeller located in the upper section is located at a point 1 / 4 to 1 / 2 of the way from the bottom of the reaction vessel.

4. The positive electrode active material precursor manufacturing apparatus according to claim 1, wherein the two stages of the impeller are inclined to have the same angle with respect to the horizontal direction.

5. The positive electrode active material precursor manufacturing apparatus according to claim 1, wherein the two-stage impeller has a diameter of 400 to 1550 mm.

6. The positive electrode active material precursor manufacturing apparatus according to claim 1, wherein the input piping has a diameter of 5 to 80 mm.

7. The positive electrode active material precursor manufacturing apparatus according to claim 1, wherein the input piping has a thickness of 1 to 15 mm.

8. The aforementioned input piping is NH ４ The cathode active material precursor manufacturing apparatus according to claim 1, comprising a first input pipe for introducing a first solution containing OH, a second input pipe for introducing a second solution containing NaOH, and a third input pipe for introducing a metal solution.

9. The cathode active material precursor manufacturing apparatus according to claim 1, wherein the input piping further includes a deionized water input piping and a nitrogen input piping.

10. The positive electrode active material precursor manufacturing apparatus according to claim 1, wherein the input piping is made of at least one material from stainless steel, PP, PVC, PE, and PVDF.

11. The cathode active material precursor manufacturing apparatus according to claim 8, wherein the first input pipe and the third input pipe are arranged adjacent to each other.

12. The positive electrode active material precursor manufacturing apparatus according to claim 1, wherein the input piping is branched into 3 to 4 branches from the branching point.

13. The step of adding the initial solution to the reaction vessel; The step of adding the reaction solution to the reaction vessel into which the initial solution has been added; and The step of stirring the initial solution and the reaction solution with a stirring means to obtain a positive electrode active material precursor; The stirring means includes a shaft and a two-stage impeller. The impeller has an angle of 5 to 90° with respect to the horizontal direction. The initial solution is poured in so that the two stages of the impeller are completely submerged. A method for producing a positive electrode active material precursor.

14. The method for producing a positive electrode active material precursor according to claim 13, wherein the initial solution includes deionized water.

15. The reaction solution is NH ４ A method for producing a positive electrode active material precursor according to claim 13, comprising a first solution containing OH, a second solution containing NaOH, and a metal solution.

16. The method for producing a positive electrode active material precursor according to claim 14, wherein the initial solution further comprises a portion of the first solution and a portion of the second solution.

17. The method for producing a positive electrode active material precursor according to claim 13, wherein the steps of adding the reaction solution and stirring the initial solution and the reaction solution with a stirring means to obtain a positive electrode active material precursor are performed simultaneously.

18. The metal ions in the metal solution and the NH ４ The method for producing a positive electrode active material precursor according to claim 15, wherein the molar ratio of OH is 1:0.2 to 1:0.

9.

19. The method for producing a positive electrode active material precursor according to claim 15, wherein the molar ratio of metal ions in the metal solution to NaOH is 1:1.5 to 1:2.

5.

20. The method for producing a positive electrode active material precursor according to claim 15, wherein the second solution is introduced at a flow rate of 40 to 1800 kg / h.

21. The method for producing a positive electrode active material precursor according to claim 15, wherein the metal solution is introduced at a flow rate of 80 to 3200 kg / h.

22. The method for producing a positive electrode active material precursor according to claim 13, wherein the positive electrode active material precursor has a Na content of 550 ppm or less.

23. The method for producing a positive electrode active material precursor according to claim 13, wherein the positive electrode active material precursor has an S content of 5000 ppm or less.

Images