Anode powder and methods for producing anode powder.

Abstract

The invention relates to a powdered anode material consisting of lithium composite transition metal oxides comprising nickel, cobalt, manganese, and zirconium, where the degree of single grain formation determined by equation 1 is between 2.5 and 4.5, and a method for producing a powdered anode material, which includes a quaternary sintering process and doping zirconium and a D50 of controlled transition metal-containing precursor to 95% or less than the D50 of the powdered anode material, as a method for producing them.

Description

Cathode material powder and method for producing the cathode material powder This application claims the benefit of priority to Korean Patent Application No. 10-2023-0132929, filed October 5, 2023, and Korean Patent Application No. 10-2024-0134975, filed October 4, 2024, the entire contents of which are incorporated herein by reference. The present invention relates to a cathode material powder having controlled particle size and particle strength, a method for producing the same, a cathode material including the cathode material powder, and a lithium secondary battery. A lithium secondary battery is generally composed of a positive electrode, a negative electrode, a separator, and an electrolyte, and the positive electrode and negative electrode include an active material capable of intercalating and deintercalating lithium ions. Among these, lithium composite transition metal oxides containing two or more transition metals, which were developed to complement the problems of lithium composite transition metal oxides containing only Ni, Co, or Mn, are attracting attention as positive electrode active materials, and among these, lithium nickel cobalt manganese oxide containing Ni, Co, and Mn is widely used in the field of electric vehicle batteries. Conventional lithium nickel cobalt manganese oxides are generally in the form of spherical secondary particles formed by agglomeration of tens to hundreds of primary particles. However, when lithium nickel cobalt manganese oxides formed in the form of secondary particles formed by agglomeration of many primary particles are used, there is a problem in that the primary particles are likely to break during the rolling process during the manufacture of the positive electrode, and cracks may occur inside the particles during the charge and discharge process. When the positive electrode active material particles break or crack, the contact area with the electrolyte increases, which increases gas generation and active material degradation due to side reactions with the electrolyte, and this causes problems in that the life characteristics are reduced. To address the above issues, a technology has been proposed for producing single-particle positive electrode active materials rather than secondary particles by increasing the sintering temperature during the production of lithium nickel cobalt manganese oxide. Single-particle positive electrode active materials have a smaller contact area with the electrolyte than conventional secondary particle positive electrode active materials, resulting in less side reactions with the electrolyte. Furthermore, their superior particle strength reduces particle breakage during electrode production, offering the advantage of superior particle strength. However, a single particle type cathode active material may experience aggregation between multiple particles during the sintering process for manufacturing, which may result in uneven particle size distribution and problems such as reduced life characteristics and increased resistance. As a solution to the problem of particle size non-uniformity of the positive electrode active material, a separate post-processing process, such as grinding, can be introduced after the calcination process, which can enable uniform particle distribution of the positive electrode active material. However, excessive post-processing may increase fine particles, and this increase in fine particles may have a negative effect on the high-temperature performance of lithium secondary batteries. The present invention aims to contribute to improving the high-temperature durability and lifespan of lithium secondary batteries by providing a cathode material powder with controlled particle size and particle strength and a method for producing the same. [1] The present invention provides a cathode material powder comprising a lithium composite transition metal oxide including nickel, cobalt, manganese and zirconium, and having a particle size distribution of 2.5 or more and 4.5 or less according to the following formula 1. [Formula 1] In the above equation 1, R i is the radius (㎛) of the i-th grain measured when the electrode manufactured by applying the above cathode material powder is subjected to ion milling treatment and then the electrode is analyzed by backscatter electron diffraction (EBSD). n is the total number of grains measured through the above EBSD analysis, which is 350 to 450. [2] The present invention provides a cathode material powder having a pellet density change of 2.5 or less according to the following formula 2 in the above [1]. [Formula 2] {(P 12ton -P 1.5ton ) / 10.5}×20 In the above equation 2, P 1.5ton The above cathode material powder is placed in a circular mold with a diameter of 13 mm and pressed with a force of 1,500 kgf to manufacture a pellet, and the pellet density (g / cc) is calculated by dividing the weight of the cathode material powder by the volume of the pellet. P 12ton The above cathode material powder is placed in a circular mold with a diameter of 13 mm and pressed with a force of 12,000 kgf to manufacture a pellet, and the pellet density (g / cc) is calculated by dividing the weight of the cathode material powder by the volume of the pellet. [3] The present invention provides a cathode material powder in which the weight of zirconium is 300 ppm to 1,000 ppm based on the total weight of the lithium composite transition metal oxide in the above [1] or [2]. [4] The present invention, in at least one of the above [1] to [3], D 50 This provides a cathode material powder having a size of 3㎛ to 6㎛. [5] The present invention provides a cathode material powder having a tap density of 1.8 g / cc to 2.3 g / cc in at least one of the above [1] to [4]. [6] The present invention provides a cathode material powder having an average grain diameter of 0.5 µm to 4.0 µm in at least one of the above [1] to [5]. [7] The present invention provides a cathode material powder, wherein, in at least one of the above [1] to [6], when the cathode material powder is placed in a circular mold having a diameter of 13 mm and pressurized with a force of 12,000 kgf, the rate of generation of fine particles having a particle diameter of 1 ㎛ or less is 2 vol% or less based on the total volume of the cathode material powder. [8] The present invention provides a cathode material powder, wherein, in at least one of the above [1] to [7], the lithium composite transition metal oxide has a composition represented by the following chemical formula 1. [Chemical Formula 1] Li 1+x (Ni a Co b Mn c Zr d M1 e )O2 In the above chemical formula 1, M1 is at least one selected from the group consisting of Al, Ti, W, Mo, Nb, Cu, Fe, V, Cr, Zn, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Mg and B, x, a, b, c, d, and e are 0≤x≤0.50, 0.55≤a<1, 0, respectively. <b≤0.40, 0<c≤0.40, 0<d≤0.01, 0≤e≤0.10, a+b+c+d+e=1을 만족한다. [9] The present invention provides a cathode material powder, wherein the content of nickel among the metals other than lithium in the lithium composite transition metal oxide is 70 mol% or more, in at least one of the above [1] to [8].

[0010] The present invention comprises a first step of preparing a first mixture by mixing a transition metal-containing precursor including nickel, cobalt and manganese with a lithium raw material; A second step of manufacturing a first sintered body by first firing the first mixture at 500°C to 700°C and second firing it at 700°C to 950°C; A third step of preparing a second mixture by mixing the first sintered body with a zirconium raw material; and A fourth step of producing a second sintered body in the form of single particles or pseudo-single particles by firing the second mixture a third time at 650°C to 900°C and a fourth time at 650°C to 950°C; and Including a fifth step of milling the above-mentioned sintered body, A method for manufacturing a cathode material powder satisfying the following equation 3 is provided. [Formula 3] A≤0.95B In the above equation 3, A is D of the above transition metal-containing precursor 50 And, B is D of the above cathode powder 50 am.

[0011] The present invention provides a method for manufacturing a cathode material powder, wherein the milling in the fifth step in the above

[0010] is performed at a speed of 1,500 rpm to 3,000 rpm.

[0012] The present invention provides a method for producing a cathode material powder in which B in the above formula 3 is 3 µm to 6 µm in the above

[0010] or

[0011] .

[0013] The present invention provides a cathode comprising at least one cathode material powder among the above [1] to [9].

[0014] The present invention provides a lithium secondary battery comprising the positive electrode of the above

[0013] ; a negative electrode including a negative electrode active material; a separator interposed between the positive electrode and the negative electrode; and an electrolyte. The cathode material powder according to the present invention has a high degree of single particle size and excellent particle strength, thereby minimizing particle breakage during rolling. Therefore, when using the cathode material powder, a cathode with a high energy density per unit volume can be manufactured by increasing the rolling intensity. In addition, when fine particles are generated due to particle breakage during rolling, the contact area with the electrolyte increases, which increases the amount of gas generated due to side reactions, and this may lead to degradation of the cathode material and deterioration of the life characteristics of the battery. However, the cathode material powder according to the present invention can contribute to solving this problem because it has a low rate of fine particle generation during rolling. Meanwhile, since it is easy to achieve a desired particle size while slightly controlling the intensity of the milling process by using the method for manufacturing the cathode material powder according to the present invention, the problems of fine powder generation and sphericity reduction due to milling can be solved. Figure 1 is a diagram measuring the change in pellet density according to the pressing force applied to the cathode material powder of the examples and comparative examples. Figure 2 is a diagram showing the capacity retention rate according to a high temperature cycle for cells including cathode material powders of examples and comparative examples. Figure 3 is a diagram showing the amount of gas generated during high-temperature storage for cells containing cathode material powders of examples and comparative examples. Figure 4 is a photograph of the cathode material powder manufactured in Example 1 observed using a scanning electron microscope. Figure 5 is a photograph of the cathode material powder manufactured in Comparative Example 1 observed using a scanning electron microscope. Figure 6 is a photograph of the cathode material powder manufactured in Comparative Example 2 observed using a scanning electron microscope. Figure 7 is a photograph of the cathode material powder manufactured in Comparative Example 3 observed using a scanning electron microscope. Hereinafter, the present invention will be described in more detail to help understand the present invention. In the present invention, a "grain" is a particle unit having the same crystal orientation, and is the smallest particle unit recognized as a single lump in an Electron Backscatter Diffraction (EBSD) map image. The size of the grain can be measured by image analysis of the EBSD map. In the present invention, “single particle” means a particle composed of one nodule, and “quasi-single particle” means a composite particle composed of 30 or fewer nodules. The above "nodule" is a sub-particle unit that constitutes a single particle and a pseudo-single particle, and may be a single crystal without a crystalline grain boundary, or a polycrystal with no apparent grain boundary when observed under a magnification of 5,000 to 20,000 times using a scanning electron microscope. In the present invention, “particle” is a concept including one or all of a single particle, a pseudo-single particle, a primary particle, and a nodule. In the present invention, "D 50 " refers to the particle size corresponding to 50% of the volume accumulation in the volume accumulation particle size distribution of the corresponding particle powder, and can be measured using a laser diffraction method. For example, after dispersing the cathode material powder in a dispersion medium, it can be measured by introducing it into a commercially available laser diffraction particle size measuring device (e.g., Malvern, Mastersizer 3000) and irradiating it with ultrasonic waves of about 28 kHz at an output of 60 W, obtaining a volume accumulation particle size distribution graph, and finding the particle size at the point where the volume accumulation amount is 50% in the obtained volume accumulation particle size distribution graph. In the present invention, "pellet density" can be obtained by placing a certain amount of sample in a cylindrical load cell or a circular mold, applying force to compress it into a pellet shape, and then calculating the density from the volume and weight of the pellet. For example, it can be measured using an automatic pellet press (Auto Pellet Press, 3887.4) from Carver. In the present invention, "tap density" can be measured using a method commonly used in the art for measuring the degree of filling of a sample per unit volume. For example, it can be the density (sample weight / volume) calculated from the change in volume by applying a constant force to a measuring container containing a sample according to the measuring device and method specified in ASTM B527. Specifically, it can be measured using a GEOPYC 1360 tap density meter from Micromeritics by vibrating it horizontally until a force of 108 N is applied. Below, each component of the present invention is described in more detail. cathode powder According to one embodiment of the present invention, a cathode powder comprises a lithium composite transition metal oxide comprising nickel, cobalt, manganese, and zirconium. In addition, the cathode powder has a particle size distribution of 2.5 or more and 4.5 or less according to the following formula 1. [Formula 1] In the above equation 1, R i is the radius (㎛) of the i-th grain measured when the electrode manufactured by applying the above cathode material powder is subjected to ion milling treatment and then the electrode is analyzed by backscatter electron diffraction (EBSD). n is the total number of grains measured through the above EBSD analysis, which is 350 to 450. The cathode material powder according to the present invention includes cathode active material particles in the form of single particles or pseudo-single particles, so that compared to conventional secondary particle-shaped cathode active materials, the contact area with the electrolyte is small, so that side reactions with the electrolyte are small, and the particle strength is excellent, so that there is an advantage of less particle breakage during electrode manufacturing. In manufacturing a cathode material powder containing cathode active material particles in the form of single particles or pseudo-single particles, a pulverization process such as milling is performed after the sintering step to obtain a target particle size. However, if a precursor larger than the target size is used or the particle agglomeration phenomenon is severe during the high-temperature sintering process applied to form single particles, the pulverization process must be performed under conditions capable of applying a strong impact. In this case, the strong pulverization process may generate a large amount of fine powder and reduce the degree of sphericity. As previously explained, this can lead to problems such as reduced high-temperature life and increased gas generation, and therefore the present invention seeks to solve these problems. Specifically, the present inventors have found that the precursor D 50 D of the cathode powder targeting 50 It was confirmed that the single particle magnetization degree according to the above equation 1 could be controlled within the optimal numerical range by regulating the milling conditions to less than 95% of the contrast and doping zirconium as a flux contributing to particle growth. More specifically, the cathode material powder may have a single particle size ratio of 2.6 or more, 2.8 or more, or 3.0 or more according to the following Equation 1. The higher the single particle size ratio, the more cathode active material particles with a small number of grains, i.e., particles in the form of single particles, are present in the cathode material powder, thereby improving high-temperature performance. However, if the single particle size ratio exceeds 4.5, the resistance may become excessively high, thereby deteriorating the output and capacity characteristics. Therefore, the single particle size ratio may be 4.5 or less, 4.0 or less, or 3.5 or less. Meanwhile, R in the above formula 1 i may be 0.4 to 2.5, 0.8 to 2.0, or 0.8 to 1.8. The grain radius substituted into the above equation 1 is a value measured in μm, or a dimensionless number that does not include a unit. In addition, the average grain diameter of the cathode material powder measured through EBSD may be 0.5 µm to 4.0 µm, preferably 0.8 µm to 3.0 µm, and more preferably 2.2 µm to 2.5 µm. When the average grain diameter of the cathode material powder satisfies the above range, that is, when the grains are formed large, the grain boundary decreases and the surface area becomes small, so that the rock salt phase generated in the lithium composite transition metal oxide during cycling or exposure to moisture is reduced, resulting in better resistance characteristics. Meanwhile, the above cathode material powder may have a pellet density change of 2.5 or less, preferably 2.3 or less, and more preferably 2.2 or less according to the following Equation 2. A low pellet density change means that the slope of the graph measuring pellet density according to load, as in Fig. 1, is gentle, which means that the pellet density is less affected by the pressing force, and thus can be interpreted as showing excellent particle strength characteristics. [Formula 2] {(P 12ton -P 1.5ton ) / 10.5}×20 In the above equation 2, P 1.5ton The above cathode material powder is placed in a circular mold with a diameter of 13 mm and pressed with a force of 1,500 kgf to manufacture a pellet, and the pellet density (g / cc) is calculated by dividing the weight of the cathode material powder by the volume of the pellet. P 12ton The above cathode material powder is placed in a circular mold with a diameter of 13 mm and pressed with a force of 12,000 kgf to manufacture a pellet, and the pellet density (g / cc) is calculated by dividing the weight of the cathode material powder by the volume of the pellet. P in the above equation 2 1.5ton can be 2.5 to 3.0, specifically 2.6 to 2.9, and P 12ton may be 3.6 to 4.1, specifically 3.7 to 4.0. The pellet density substituted into the above equation 2 is a value measured in g / cc units, or a dimensionless number that does not include units. Meanwhile, the cathode material powder may be a single particle composed of one nodule and / or a quasi-single particle which is a composite of 30 or fewer, preferably 2 to 20, and more preferably 2 to 10 nodules, or may be in a form including these. Preferably, the cathode material powder according to the present invention may be composed of a combination of single particles and quasi-single particle-type cathode active material particles. When the number of nodules constituting the cathode active material particles exceeds 30, particle breakage increases during electrode manufacturing, and internal cracks occur more due to volume expansion / contraction of the nodules during charge / discharge, which may deteriorate the effect of improving high-temperature life characteristics and high-temperature storage characteristics. In addition, D of the above cathode powder 50 The diameter of the electrode may be 3.0 μm to 6.0 μm, preferably 3.5 μm to 4.7 μm. In order to ensure fairness in electrode manufacturing, D 50 It is preferable that it be 3.0㎛ or more, but it is preferable that it be 6.0㎛ or less to improve electrolyte impregnation and prevent excessive resistance increase. In addition, when the cathode material powder is placed in a circular mold with a diameter of 13 mm and pressurized with a force of 12,000 kgf, the rate of generation of fine particles having a particle diameter of 1 μm or less may be 2 vol% or less, preferably 1.8 vol% or less, and more preferably 1.5 vol% or less, based on the total volume of the cathode material powder. In this case, since the particles have excellent durability against rolling, not only can the energy density be increased by increasing the rolling intensity as needed, but also the amount of gas generated due to side reactions during operation or storage at high temperatures can be reduced and the lifespan can be improved. Meanwhile, according to one embodiment of the present invention, the content of nickel among the metals other than lithium in the lithium composite transition metal oxide may be 70 mol% or more, preferably 80 mol% or more, more preferably 90 mol% or more, but may be 99 mol% or less. In this case, there is an advantage of being able to implement high capacity. In addition, the above-mentioned composite lithium composite transition metal oxide may have a composition represented by the following chemical formula 1. [Chemical Formula 1] Li 1+x (Ni a Co b Mn c Zr d M1 e )O2 In the above chemical formula 1, M1 is at least one selected from the group consisting of Al, Ti, W, Mo, Nb, Cu, Fe, V, Cr, Zn, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Mg and B, x, a, b, c, d, and e are 0≤x≤0.50, 0.55≤a<1, 0, respectively. <b≤0.40, 0<c≤0.40, 0<d≤0.01, 0≤e≤0.10, a+b+c+d+e=1을 만족한다. The above 1+x represents the molar ratio of lithium in the lithium composite transition metal oxide, and may be 0≤x≤0.20, or 0≤x≤0.10. When the molar ratio of lithium satisfies the above range, the crystal structure can be formed stably. The above a represents the molar ratio of nickel among the total metals excluding lithium in the lithium composite transition metal oxide, and may be 0.80≤a<1, 0.90≤a<1, or 0.93≤a<1. When the molar ratio of nickel satisfies the above range, a high energy density is exhibited, enabling high capacity implementation. The above b represents the molar ratio of cobalt among all metals excluding lithium in the lithium composite transition metal oxide, and is 0. <b≤0.15, 0<b≤0.08, 또는 0<b≤0.05일 수 있다. 코발트의 몰비가 상기 범위를 만족할 때, 양호한 저항 특성 및 출력 특성을 구현할 수 있다. The above c represents the molar ratio of manganese among all metals excluding lithium in the lithium composite transition metal oxide, and is 0. <c≤0.10, 0<c≤0.05, 또는 0<c≤0.03일 수 있다. 망간의 몰비가 상기 범위를 만족할 때, 양극재의 구조 안정성이 우수하게 나타난다. The above d represents the molar ratio of zirconium among all metals excluding lithium in the lithium composite transition metal oxide, and the above d is 0. <d≤0.008, 0<d≤0.005, 또는 0<d≤0.001일 수 있다. The above e represents the molar ratio of the M1 element among all metals excluding lithium in the lithium composite transition metal oxide, and can be adjusted as needed. Meanwhile, the weight of the zirconium may be 300 ppm or more, 400 ppm or more, or 500 ppm or more based on the total weight of the lithium composite transition metal oxide. In this case, not only can the particle growth effect due to the flux effect be observed, but it is also preferable in terms of preventing cation mixing between lithium ions and nickel ions. However, considering that excessive doping may cause a decrease in capacity and gelation during subsequent slurry production, it is preferable that it does not exceed 1,000 ppm. Method for manufacturing cathode material powder Hereinafter, a method for manufacturing a cathode material powder according to the present invention will be described. A method for manufacturing a cathode material powder according to one embodiment of the present invention comprises: a first step of mixing a transition metal-containing precursor including nickel, cobalt, and manganese with a lithium raw material to prepare a first mixture; a second step of first firing the first mixture at 500°C to 700°C and a second firing at 700°C to 950°C to prepare a first sintered body; a third step of mixing the first sintered body with a zirconium raw material to prepare a second mixture; and a fourth step of third firing the second mixture at 650°C to 900°C and a fourth firing at 650°C to 950°C to prepare a second sintered body in the form of single particles or pseudo-single particles; and a fifth step of milling the second sintered body, while simultaneously satisfying the following Equation 3. [Formula 3] A≤0.95B In the above equation 3, A is D of the above transition metal-containing precursor 50 And, B is D of the above cathode powder 50 am. In this way, the precursor D 50 D of the cathode powder targeting 50 By adjusting the contrast to 95% or less, the milling conditions that occur after firing can be relaxed, thereby reducing the amount of impact applied, ultimately reducing the rate of fine particle generation and increasing the degree of sphericity. Specifically, the above A may be 0.85B≤A≤0.95B, or 0.90B≤A≤0.93B. Next, each step is explained. 1) Stage 1 First, a first mixture is prepared by mixing a transition metal-containing precursor including nickel, cobalt, and manganese with a lithium raw material in a reactor. Meanwhile, the transition metal-containing precursor may be in the form of a hydroxide, oxide or carbonate, and specifically may be in the form of a hydroxide, and more specifically may have a composition represented by the following chemical formula 2. [Chemical Formula 2] Ni a1 Co b1 Mn c1 M1 d1 (OH)2 In the above chemical formula 2, M1 is at least one selected from the group consisting of Al, Ti, W, Mo, Nb, Cu, Fe, V, Cr, Zn, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Mg and B, x, a, b, c, d, and e are 0≤x≤0.50, 0.55≤a<1, 0, respectively. <b≤0.40, 0<c≤0.40, 0<d≤0.10, 0≤e≤0.10, a+b+c+d+e=1을 만족한다. The above a1 represents the molar ratio of nickel among the total metal in the precursor, and may be 0.80≤a1<1, 0.90≤a1<1, or 0.93≤a1<1. The above b1 represents the molar ratio of cobalt among the total metals in the precursor, 0 <b1≤0.15, 0<b1≤0.08, 또는 0<b1≤0.05일 수 있다. The above c1 represents the molar ratio of manganese among the total metals in the precursor, 0 <c1≤0.10, 0<c1≤0.05, 또는 0<c1≤0.03일 수 있다. The above d1 represents the molar ratio of the M1 element among the total metals in the precursor, and the above 0 <d1≤0.08, 0<d1≤0.05, 또는 0<d1≤0.03일 수 있다. Meanwhile, the method for manufacturing the cathode material powder may further include a step of manufacturing the transition metal-containing precursor. Specifically, the method may further include a step of dissolving a nickel precursor, a cobalt precursor, and a manganese precursor in a solvent in a reactor to manufacture a transition metal-containing solution; and a step of supplying the transition metal-containing solution, an ammonium cation complex forming agent, and a basic compound while performing a co-precipitation reaction to form a transition metal-containing precursor comprising nickel, cobalt, and manganese. If necessary, an oxidizing agent or oxygen gas may be further added during the co-precipitation reaction. Meanwhile, the transition metal precursor may be an acetate, carbonate, nitrate, sulfate, halide, sulfide, etc. of each transition metal. Specifically, the nickel precursor may be at least one selected from the group consisting of NiO, NiCO3·2Ni(OH)2·4H2O, NiC2O2·2H2O, Ni(NO3)2·6H2O, NiSO4, NiSO4·6H2O, and nickel sulfide, and the cobalt precursor may be at least one selected from the group consisting of Co(OH)2, Co3O4, CoOOH, Co(OCOCH3)2·4H2O, Co(NO3)2·6H2O, and Co(SO4)2·7H2O. In addition, the manganese precursor may be at least one selected from the group consisting of Mn2O3, MnO2, Mn3O4, MnCO3, Mn(NO3)2, MnSO4·H2O, manganese acetate, manganese halides, and manganese sulfide. At this time, the input amount of each transition metal precursor can be determined by considering the molar ratio of the transition metal in the cathode material to be ultimately produced. Meanwhile, the ammonium cation complex forming agent may include at least one compound selected from the group consisting of NH4OH, (NH4)2SO4, NH4NO3, NH4Cl, CH3COONH4, and (NH4)2CO3, and may be introduced into the reactor in the form of a solution in which the compound is dissolved in a solvent. At this time, the solvent may be water or a mixture of water and an organic solvent (specifically, alcohol, etc.) that can be uniformly mixed with water. The basic compound may be at least one compound selected from the group consisting of NaOH, KOH, and Ca(OH)2, and may be introduced into the reactor in the form of a solution in which the compound is dissolved in a solvent. At this time, the solvent may be water, or a mixture of water and an organic solvent (specifically, alcohol, etc.) that can be uniformly mixed with water. As described above, when a transition metal-containing solution, an ammonium cation complex forming agent, and a basic compound are introduced into a reactor and stirred, the transition metals in the transition metal-containing solution coprecipitate, generating precursor particles in the form of transition metal hydroxides. At this time, the transition metal-containing solution, ammonium cation complex forming agent, and basic compound are added in an amount such that the pH of the reaction solution becomes within the desired range. Once precursor particles are formed in the above manner, they are separated from the reaction solution to obtain the precursor. For example, the precursor can be separated from the reaction solution by filtering the reaction solution, and then the separated precursor can be washed and dried to obtain the precursor. Processes such as grinding and / or classification may also be performed as needed. As the above lithium raw material, lithium-containing sulfate, nitrate, acetate, carbonate, oxalate, citrate, halide, hydroxide or oxyhydroxide may be used, and for example, Li2CO3, LiNO3, LiNO2, LiOH, LiOHㆍH2O, LiH, LiF, LiCl, LiBr, LiI, CH3COOLi, Li2O, Li2SO4, CH3COOLi, Li3C6H5O7 or a mixture thereof may be used. Meanwhile, the lithium raw material and the transition metal-containing precursor may be mixed so that the molar ratio of Li:total metal in the precursor is 1:1 to 1.2:1, preferably 1:1 to 1.1:1. When the mixing ratio of the lithium raw material and the metal in the precursor satisfies the above range, the layered crystal structure of the lithium composite transition metal oxide is well developed, so that a cathode material with excellent capacity characteristics and structural stability can be manufactured. 2) Stage 2 After the first step, a step of producing a first sintered body is performed by first firing the first mixture produced in the first step at 500°C to 900°C and second firing it at 700°C to 1,000°C. The above first firing can be performed at 500°C to 900°C, preferably 550°C to 800°C, and more preferably 600°C to 650°C, under an oxygen atmosphere. The above first firing can be performed for 1 to 2 hours. Primary calcination involves mixing the lithium source and precursor and then calcining them. When performed at temperatures above 500°C, moisture in the precursor and lithium source evaporates, increasing the loading amount. This is desirable for reducing processing costs. However, excessively high calcination temperatures can hinder lithiation, so it is recommended that temperatures not exceed 900°C. The above secondary firing can be performed at 700°C to 1,000°C, preferably 720°C to 900°C, and more preferably 750°C to 850°C, under an oxygen atmosphere. The above secondary firing can be performed for 4 to 6 hours. The secondary sintering is a step in which the basic layered structure of the positive electrode active material is completed and the overall level of single crystallinity is determined. Therefore, considering that the higher the sintering temperature, the better the particle growth reaction occurs, which can increase the single particle degree, it is preferable to have a temperature of 700℃ or higher. However, if the content of Li2O increases due to high-temperature sintering, it is easily converted to LiOH, and LiOH is easily converted again to Li2CO3, which can cause side reactions with the electrolyte and gas generation. Therefore, it is preferable to have a temperature of 1,000℃ or lower. In this specification, an oxygen atmosphere means an atmosphere containing oxygen sufficient for sintering, including an air atmosphere. In particular, it is preferable to perform the sintering in an atmosphere in which the oxygen partial pressure is higher than that of the air atmosphere. As described above, if firing is performed two or more times after the lithium raw material is introduced, the amount of charge can be increased, which is desirable in terms of reducing processing costs. 3) Stage 3 After the second step, the first sintered body is mixed with a zirconium raw material to produce a second mixture. When zirconium raw materials are added simultaneously with lithium raw materials and fired simultaneously, there is a problem in which the doping temperature and the firing temperature do not match, resulting in uneven doping. On the other hand, when the process of adding the lithium raw material, firing it, and then adding the zirconium raw material and firing it again is performed as in the present invention, this problem can be solved. Meanwhile, the zirconium raw material may be at least one selected from the group consisting of ZrO2, Zr(OH)4, and Zr(SO4)2. The above zirconium raw material can be mixed in an amount such that the weight of the zirconium is 300 ppm to 1,000 ppm based on the total weight of the lithium composite transition metal oxide. 4) Step 4 After the third step, a step of producing a second sintered body in the form of single particles or pseudo-single particles is performed by firing the second mixture a third time at 650°C to 900°C and a fourth time at 650°C to 950°C. The above third firing can be performed at 650°C to 900°C, preferably 670°C to 880°C, and more preferably 700°C to 850°C, under an oxygen atmosphere. The above third firing can be performed for 6 to 10 hours. The third firing is a step in which doping takes place, and when the third firing temperature is within the above range, doping progresses uniformly, which has the effect of improving crystallinity. The fourth firing can be performed at 650°C to 950°C, preferably 670°C to 930°C, and more preferably 700°C to 900°C, under an oxygen atmosphere. The fourth firing can be performed for 4 to 8 hours. The fourth firing is a high-temperature heat treatment step. The higher the firing temperature, the more uniformly the primary particles grow, forming an even particle surface and reducing the amount of fine particles generated. Therefore, the fourth firing temperature is preferably 650°C or higher. However, if the firing temperature is too high, growth becomes uneven and it is difficult to achieve the target particle size, so it is preferable that it not exceed 950°C. A crushing process may be performed between the third and fourth firings. Meanwhile, when firing is performed two or more times after the lithium raw material is introduced as described above, it is preferable in that it can prevent damage to the particle surface and reduce the amount of fine particles generated. 5) Step 5 After the fourth step, a step of milling the second sintered body is performed. The above milling process is to remove large particles and obtain a particle size of the cathode powder within a desired numerical range. During the high-temperature firing process in the second and fourth steps, coagulation and / or agglomeration between adjacent particles may occur, resulting in the generation of large particles, which may lead to a deterioration in rolling characteristics. Therefore, in the present invention, by performing a milling process, large particles are removed and the desired D is finally obtained. 50 It enables the formation of a cathode material powder having . As described above, since the present invention uses a limited precursor particle size, the impact force applied to the sintered body can be lowered and the amount of fine powder generated can be reduced by making the milling conditions more relaxed. The above milling can be performed using a general milling method known in the art, for example, a jet-mill method. The above milling can be performed at a speed of, for example, 1,500 rpm to 3,000 rpm, specifically 1,500 rpm to 2,500 rpm, and the speed refers to a classifier speed. Meanwhile, it is preferable that the above milling be performed in an atmosphere with little moisture, such as a dry air atmosphere. This is because exposure of the lithium composite transition metal oxide to moisture increases the generation of lithium byproducts and may deteriorate the surface properties of the active material. anode Next, the anode according to the present invention will be described. The positive electrode according to the present invention comprises the aforementioned positive electrode material powder. Specifically, the positive electrode comprises: a positive electrode current collector; and a positive electrode active material layer formed on the positive electrode current collector and comprising the positive electrode material powder. Since the positive electrode material powder has been described above, a description thereof will be omitted, and components other than the positive electrode material powder will be described below. In the above positive electrode, the positive electrode current collector is not particularly limited as long as it is conductive and does not cause a chemical change in the battery, and for example, stainless steel, aluminum, nickel, titanium, calcined carbon, or aluminum or stainless steel surface-treated with carbon, nickel, titanium, silver, etc. may be used. In addition, the positive electrode current collector may typically have a thickness of 3 to 500 ㎛, and fine unevenness may be formed on the surface of the positive electrode current collector to increase the adhesive strength of the positive electrode material powder. For example, it may be used in various forms such as a film, sheet, foil, net, porous body, foam, or non-woven fabric. Additionally, the positive electrode active material layer may include a conductive material and a binder together with the positive electrode material powder described above. The above cathode material powder may typically be included in an amount of 80 wt% to 99 wt%, preferably 90 wt% to 98 wt%, and more preferably 95 wt% to 97 wt%, based on the total weight of the cathode active material layer. The conductive material is used to provide conductivity to the electrode, and in the battery to be formed, as long as it does not cause a chemical change and has electronic conductivity, it can be used without any particular limitation. Specific examples include graphite such as natural graphite or artificial graphite; carbon black such as acetylene black, Ketjen black, channel black, furnace black, lamp black, and summer black; carbon-based materials such as carbon fibers and carbon nanotubes; metal powders or metal fibers such as copper, nickel, aluminum, and silver; conductive whiskers such as zinc oxide and potassium titanate; conductive metal oxides such as titanium oxide; or conductive polymers such as polyphenylene derivatives, and the like. One of these may be used alone or a mixture of two or more may be used. The conductive material may typically be included in an amount of 0.5 wt% to 20 wt%, preferably 1 wt% to 10 wt%, and more preferably 1 wt% to 5 wt%, based on the total weight of the positive electrode active material layer. The above binder serves to improve adhesion between positive electrode active material particles and adhesion between the positive electrode active material and the positive electrode current collector. Specific examples thereof include polyvinylidene fluoride (PVDF), vinylidene fluoride-hexafluoropropylene copolymer (PVDF-co-HFP), polyvinyl alcohol, polyacrylonitrile, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinyl pyrrolidone, polytetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene monomer rubber (EPDM rubber), sulfonated-EPDM, styrene butadiene rubber (SBR), fluororubber, or various copolymers thereof, and one of these may be used alone or a mixture of two or more thereof. The above binder may be included in an amount of 0.5 wt% to 20 wt%, preferably 1 wt% to 10 wt%, and more preferably 1 wt% to 5 wt%, based on the total weight of the positive electrode active material layer. The above positive electrode can be manufactured according to a conventional positive electrode manufacturing method. For example, the positive electrode can be manufactured by mixing positive electrode material powder, a binder, and / or a conductive material in a solvent to manufacture a positive electrode slurry, applying the positive electrode slurry onto a positive electrode current collector, and then drying and rolling. The solvent may be a solvent generally used in the relevant technical field, such as dimethyl sulfoxide (DMSO), isopropyl alcohol, N-methylpyrrolidone (NMP), acetone, or water. One of these may be used alone or a mixture of two or more thereof may be used. The amount of the solvent used is sufficient to dissolve or disperse the cathode powder, conductive material, and binder, taking into account the coating thickness and manufacturing yield of the slurry, and to have a viscosity that can exhibit excellent thickness uniformity when applied thereafter for manufacturing the cathode. Alternatively, the positive electrode may be manufactured by casting the positive electrode slurry onto a separate support, then peeling the resulting film from the support and laminating it onto a positive electrode current collector. lithium secondary battery Next, a lithium secondary battery according to the present invention will be described. The lithium secondary battery specifically includes a positive electrode, a negative electrode including a negative electrode active material, and a separator and electrolyte interposed between the positive electrode and the negative electrode. Since the positive electrode is the same as described above, a detailed description will be omitted, and only the remaining components will be described in detail below. In addition, the lithium secondary battery may optionally further include a battery container that houses the electrode assembly of the positive electrode, the negative electrode, and the separator, and a sealing member that seals the battery container. In the above lithium secondary battery, the negative electrode includes a negative electrode current collector and a negative electrode active material layer positioned on the negative electrode current collector. The negative electrode current collector is not particularly limited as long as it has high conductivity without causing chemical changes in the battery, and for example, copper, stainless steel, aluminum, nickel, titanium, calcined carbon, copper or stainless steel surface-treated with carbon, nickel, titanium, silver, etc., aluminum-cadmium alloy, etc. can be used. In addition, the negative electrode current collector can typically have a thickness of 3 ㎛ to 500 ㎛, and like the positive electrode current collector, fine unevenness can be formed on the surface of the current collector to strengthen the bonding strength of the negative electrode active material. For example, it can be used in various forms such as a film, a sheet, a foil, a net, a porous body, a foam, a non-woven fabric, etc. The above negative electrode active material layer optionally includes a binder and a conductive material together with the negative electrode active material. As the negative electrode active material, a compound capable of reversible intercalation and deintercalation of lithium may be used. Specific examples include carbonaceous materials such as artificial graphite, natural graphite, graphitized carbon fiber, and amorphous carbon; metallic materials capable of alloying with lithium such as Si, Al, Sn, Pb, Zn, Bi, In, Mg, Ga, Cd, Si alloy, Sn alloy, or Al alloy; SiO β (0 <β< 2), metal oxides capable of doping and dedoping lithium, such as SnO2, vanadium oxide, and lithium vanadium oxide; or composites containing the above metallic compounds and carbonaceous materials, such as Si-C composites or Sn-C composites, and any one or a mixture of two or more of these may be used. In one embodiment of the present invention, the negative electrode active material may be graphite, the Si-containing material, or a mixture thereof, and specifically, may be graphite, and more specifically, a mixture of artificial graphite and natural graphite. In addition, a metallic lithium thin film may be used as the negative electrode active material. The negative electrode active material may be included in an amount of 80 wt% to 99 wt% based on the total weight of the negative electrode active material layer. The above binder is a component that assists in bonding between the conductive material, the active material, and the current collector, and is typically added in an amount of 0.1 wt% to 10 wt% based on the total weight of the negative electrode active material layer. Examples of such binders include polyvinylidene fluoride (PVDF), polyvinyl alcohol, carboxymethyl cellulose (CMC), starch, hydroxypropyl cellulose, regenerated cellulose, polyvinyl pyrrolidone, polytetrafluoroethylene, polyethylene, polypropylene, ethylene-propylene-diene polymer (EPDM), sulfonated-EPDM, styrene-butadiene rubber, nitrile-butadiene rubber, fluororubber, and various copolymers thereof. The conductive agent is a component for further improving the conductivity of the negative electrode active material, and may be added in an amount of 10 wt% or less, preferably 5 wt% or less, based on the total weight of the negative electrode active material layer. The conductive agent is not particularly limited as long as it has conductivity and does not cause a chemical change in the battery, and examples thereof include graphite such as natural graphite or artificial graphite; carbon black such as acetylene black, Ketjen black, channel black, furnace black, lamp black, and thermal black; conductive fibers such as carbon fiber or metal fiber; fluorinated carbon; metal powder such as aluminum or nickel powder; conductive whiskers such as zinc oxide or potassium titanate; conductive metal oxides such as titanium oxide; and conductive materials such as polyphenylene derivatives. The above negative electrode active material layer can be manufactured by applying and drying a negative electrode composite prepared by dissolving or dispersing a negative electrode active material, and optionally a binder and a conductive material in a solvent, on a negative electrode current collector, or by casting the negative electrode composite on a separate support and then laminating the obtained film by peeling it off from the support on a negative electrode current collector. Meanwhile, in the lithium secondary battery, the separator separates the negative electrode and the positive electrode and provides a passage for lithium ions to move. Any separator commonly used in lithium secondary batteries can be used without special restrictions, and in particular, one having low resistance to ion movement of the electrolyte and excellent electrolyte moisture retention capacity is preferable. Specifically, a porous polymer film, for example, a porous polymer film made of a polyolefin polymer such as an ethylene homopolymer, a propylene homopolymer, an ethylene / butene copolymer, an ethylene / hexene copolymer, and an ethylene / methacrylate copolymer, or a laminated structure of two or more layers thereof, can be used. In addition, a conventional porous nonwoven fabric, for example, a nonwoven fabric made of high-melting-point glass fiber, polyethylene terephthalate fiber, etc. can also be used. In addition, a coated separator containing a ceramic component or a polymer material to secure heat resistance or mechanical strength can be used, and can optionally be used in a single-layer or multi-layer structure. In addition, examples of the electrolyte used in the present invention include, but are not limited to, organic liquid electrolytes, inorganic liquid electrolytes, solid polymer electrolytes, gel-type polymer electrolytes, solid inorganic electrolytes, and molten inorganic electrolytes that can be used in the manufacture of lithium secondary batteries. Specifically, the electrolyte may include an organic solvent and a lithium salt. As the organic solvent, any solvent that can serve as a medium through which ions involved in the electrochemical reaction of the battery can move may be used without particular limitation. Specifically, the organic solvent includes ester solvents such as methyl acetate, ethyl acetate, γ-butyrolactone, and ε-caprolactone; ether solvents such as dibutyl ether or tetrahydrofuran; ketone solvents such as cyclohexanone; aromatic hydrocarbon solvents such as benzene and fluorobenzene; carbonate solvents such as dimethylcarbonate (DMC), diethylcarbonate (DEC), ethylmethylcarbonate (EMC), ethylene carbonate (EC), and propylene carbonate (PC); Alcohol solvents such as ethyl alcohol, isopropyl alcohol, etc.; nitriles such as R-CN (R is a linear, branched, or cyclic hydrocarbon group having 2 to 20 carbon atoms and may include a double-bonded aromatic ring or an ether bond); amides such as dimethylformamide; dioxolanes such as 1,3-dioxolane; or sulfolanes, etc. can be used. Among these, carbonate solvents are preferable, and a mixture of a cyclic carbonate (e.g., ethylene carbonate or propylene carbonate) having high ionic conductivity and high dielectric constant that can improve the charge / discharge performance of a battery and a low-viscosity linear carbonate compound (e.g., ethyl methyl carbonate, dimethyl carbonate, or diethyl carbonate) is more preferable. The above lithium salt can be used without any special limitation as long as it is a compound that can provide lithium ions used in a lithium secondary battery. Specifically, the anion of the above lithium salt is F - , Cl - , Br - , I - , NO3 - , N(CN)2 - , BF4 - , CF3CF2SO3 - , (CF3SO2)2N - , (FSO2)2N - , CF3CF2(CF3)2CO - , (CF3SO2)2CH - , (SF5)3C - , (CF3SO2)3C - , CF3(CF2)7SO3 - , CF3CO2 - , CH3CO2 - , SCN - and (CF3CF2SO2)2N - It may be at least one selected from the group consisting of, and the lithium salt may be LiPF6, LiClO4, LiAsF6, LiBF4, LiSbF6, LiAlO2, LiAlCl4, LiCF3SO3, LiC4F9SO3, LiN(C2F5SO3)2, LiN(C2F5SO2)2, LiN(CF3SO2)2, LiCl, LiI, or LiB(C2O4)2. It is preferable to use the concentration of the lithium salt within the range of 0.1 to 4.0 M. When the concentration of the lithium salt is within the above range, the electrolyte can exhibit excellent electrolyte performance because it has appropriate conductivity and viscosity, and lithium ions can move effectively. In addition to the electrolyte components, the electrolyte may further include one or more additives, such as haloalkylene carbonate compounds such as difluoroethylene carbonate, pyridine, triethyl phosphite, triethanolamine, cyclic ethers, ethylene diamine, n-glyme, hexaphosphate triamide, nitrobenzene derivatives, sulfur, quinone imine dyes, N-substituted oxazolidinones, N,N-substituted imidazolidines, ethylene glycol dialkyl ethers, ammonium salts, pyrrole, 2-methoxyethanol, or aluminum trichloride, for the purpose of improving the life characteristics of the battery, suppressing battery capacity decrease, and improving the discharge capacity of the battery. At this time, the additives may be included in an amount of 0.1 to 5 wt% based on the total weight of the electrolyte. There is no particular limitation on the external shape of the lithium secondary battery of the present invention, but it may be a cylindrical shape using a can, a square shape, a pouch shape, or a coin shape. As described above, since a lithium secondary battery including a cathode material powder according to the present invention exhibits stable high-temperature performance, it can be used not only as a battery cell used as a power source for small devices such as mobile phones, laptop computers, and digital cameras, but can also be preferably used as a unit battery of a battery module for medium- to large-sized devices including a plurality of battery cells. Examples of the above medium and large devices include, but are not limited to, power tools, electric vehicles, hybrid electric vehicles, plug-in hybrid electric vehicles, and power storage systems. According to another embodiment of the present invention, a battery module including the lithium secondary battery as a unit cell and a battery pack including the same are provided. Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. [Example: Preparation of cathode material powder] Example 1. D50 This is about 3.7㎛ and Ni 0.960 Co 0.030 Mn 0.010 A precursor having a composition represented by (OH)2 and LiOH were placed in a Henschel mixer (700 L) in an amount such that the molar ratio of (Ni+Co+Mn) : Li was 1:1.05, and mixed at a central speed of 400 rpm for 20 minutes. The mixed powder was placed in an alumina crucible measuring 330 mm × 330 mm, calcined at 610°C for 2 hours in an oxygen (O2) atmosphere, and then calcined again at 830°C for 4 hours. The calcined powder and ZrO2 were placed back into a Henschel mixer (700 L) and mixed at a central speed of 400 rpm for 20 minutes. At this time, ZrO2 was placed in an amount such that the weight of Zr was 500 ppm based on the total weight of the lithium composite transition metal oxide finally obtained. The mixed powder was placed in an alumina crucible measuring 330 mm × 330 mm, calcined at 780°C for 8 hours in an oxygen (O2) atmosphere, and then calcined again at 800°C for 6 hours after performing a first grinding. By milling the calcined powder using a jet-mill device at a grading speed of 2,300 rpm under a dry air atmosphere, Li[Ni 0.9595 Co 0.0300 Mn 0.0100 Zr 0.0005 ]O2 composition was prepared. Comparative Example 1. D 50 This is about 4.0㎛ and Ni 0.960 Co 0.030 Mn 0.010A precursor having a composition represented by (OH)2 and LiOH were added to a Henschel mixer (700 L) in an amount such that the molar ratio of (Ni+Co+Mn) : Li was 1:1.05, and mixed at a speed of 400 rpm in the center for 20 minutes. The mixed powder was placed in an alumina crucible measuring 330 mm × 330 mm, calcined at a temperature of 610°C for 2 hours in an oxygen (O2) atmosphere, and then calcined again at 830°C for 4 hours. The calcined powder was milled at a classification speed of 2,300 rpm in a dry air atmosphere using a jet-mill device, thereby obtaining Li[Ni 0.960 Co 0.030 Mn 0.010 ]O2 composition was prepared. Comparative Example 2. D as a precursor 50 A cathode material powder was manufactured in the same manner as in Comparative Example 1, except that the powder was approximately 3.7 μm in size. Comparative Example 3. D 50 This is about 3.7㎛ and Ni 0.960 Co 0.030 Mn 0.010 Precursors, LiOH and ZrO2 having a composition represented by (OH)2 were simultaneously introduced into a Henschel mixer (700 L) and mixed at a central speed of 400 rpm for 20 minutes. At this time, LiOH was introduced in an amount such that the molar ratio of Li:(Ni+Co+Mn) was 1.05:1, and ZrO2 was introduced in an amount such that the weight of Zr was 500 ppm based on the total weight of the lithium composite transition metal oxide finally obtained. The mixed powder was placed in an alumina crucible measuring 330 mm × 330 mm and calcined at a temperature of 830°C for 4 hours in an oxygen (O2) atmosphere, and then calcined at a temperature of 780°C for 10 hours. The calcined powder was milled at a classification speed of 2,300 rpm in a dry air atmosphere using a jet-mill device, thereby obtaining Li[Ni 0.9595 Co 0.0300 Mn0.0100 Zr 0.0005 ]O2 composition was prepared. [Experimental Example] Experimental Example 1. Powder Characteristics Evaluation (1) D 50 and SEM observation After dispersing 0.1 g of each cathode material powder manufactured in the above examples and comparative examples in a dispersion medium, it was introduced into a laser diffraction particle size measuring device (Malvern, Mastersizer 3000) and irradiated with ultrasonic waves of about 28 kHz at an output of 60 W to measure the D of each cathode material powder. 50 was measured. The measurement results are shown in Table 1 below. In addition, using a scanning electron microscope device, SEM images of each of the cathode material powders manufactured in Example 1 and Comparative Examples 1 to 3 were obtained, and these are attached to FIGS. 4 to 7, respectively. (2) Measurement of single particle magnetization Each of the cathode material powders manufactured in the above examples and comparative examples, carbon black, and PVDF binder were mixed in a weight ratio of 95:2:3 in N-methylpyrrolidone to prepare an electrode slurry. The electrode slurry was applied to one surface of an aluminum current collector and then dried at 130°C to prepare an electrode for EBSD analysis. Rolling was not performed during the manufacture of the cathode. The anode was cross-sectioned using an ion milling device (HITACHI IM-5000, accelerating voltage 6 kV), and EBSD analysis was performed on the cross-section of the anode using a FE-SEM (JEOL JSM7900F) equipped with a backscatter electron diffraction pattern analyzer (EBSD). The EBSD analysis was performed at an accelerating voltage of 15 kV, a WD of 15 mm, and a scale with a total number of grains of approximately 400+ / -10. The grain diameter of each particle observed in each anode cross-section was measured through EBSD analysis, and the half of the maximum diameter of the measured grain was calculated as the grain radius, and the arithmetic mean of the diameters of the measured grains was calculated as the average grain diameter. In addition, the grain radius and the D measured in (1) above were calculated. 50 The single particle magnetization degree was calculated by substituting into the above [Equation 1]. The measurement results are shown in Table 1 below. (3) Measurement of tap density, pellet density and fine particle generation rate The tap density of each cathode material powder manufactured in the above examples and comparative examples was measured using a GEOPYC 1360 tap density meter from Micromeritics. Specifically, 10 g of each cathode material powder manufactured in the above examples and comparative examples was filled into a container with a diameter of 19 mm, and the container was vibrated horizontally until a force of 108 N was applied to measure the tap density, which is shown in Table 1 below. In addition, 3 g each of the cathode powders manufactured in Example 1 and Comparative Examples 1 to 4 were placed into a circular mold having a diameter of 13 mm, and a force was applied until a force equivalent to 12,000 kgf was reached using an automatic pellet press (Auto Pellet Press, Carver, 3887.4), and the height of the pellets formed at intervals of 1,500 kgf was measured. Based on the measured height, the volume of the pellets was calculated, and the pellet density calculated by dividing the weight of the cathode powder by the volume of the pellets is shown in Fig. 1. In addition, the pellet density change was calculated by substituting the produced pellet density into the above [Equation 2], and this is shown in Table 1 below. Meanwhile, the pellets pressurized with the force of 12,000 kgf were dispersed again in a dispersion medium, and then the volume cumulative particle size distribution (Particle Size Distribution, PSD) was obtained using a laser diffraction particle size measuring device (Malvern, Mastersizer 3000). Based on the PSD, the volume ratio of fine particles with a particle size of 1 μm or less among the total cathode material powder was calculated, and this was recorded as the fine particle generation rate in Table 1 below. D of precursor 50 [㎛]Cathode powder D 50 [㎛]Average grain diameter [㎛]Single particle magnetization of formula 1Tap density [g / cc]Pellet density change of formula 2Differential particle generation rate [vol%]Example 13.74.022.313.052.072.131.32Comparative example 14.04.141.941.801.553.315.18Comparative example 23.74.072.041.851.603.122.36Comparative example 33.73.952.102.471.872.371.91 Through the results in Fig. 1 and Table 1, doping Zr and D of the precursor 50 and D of the cathode material powder 50In Example 1, which satisfies the above Equation 3, it can be confirmed that a cathode powder having a single particle size of 2.5 to 4.5 and a pellet density change of 2.5 or less was manufactured. In Comparative Example 1, which does not satisfy Equation 3 and is not doped with Zr, and Comparative Example 2, which satisfies Equation 3 but is not doped with Zr, a cathode powder having a single particle size of less than 2.5 was manufactured, and in Comparative Example 3, which is doped with Zr and satisfies Equation 3 but is simultaneously injected with lithium raw materials and zirconium raw materials and only twice calcined, it can be confirmed that a cathode powder having a single particle size of less than 2.5 was manufactured. In addition, Comparative Examples 1 to 3 also showed higher pellet density changes than Example 1, and in particular, Comparative Examples 1 and 2 showed pellet density changes exceeding 2.5. Meanwhile, the cathode material powder manufactured in Example 1 showed a larger average grain diameter, a higher tap density, and a lower fine particle generation rate than the cathode material powder manufactured in Comparative Examples 1 to 3. Especially the D of the precursor 50 and D of the cathode material powder 50 In Comparative Example 1, which does not satisfy Equation 3 and is not doped with Zr, a cathode powder having the smallest average grain diameter, the lowest single particle size and tap density, and the largest pellet density variation was manufactured, and it can be confirmed that the fine particle generation rate was very high at 5 vol% or more. Experimental Example 2. Coin Cell Performance Evaluation (1) Manufacturing of coin half-cells Each of the lithium composite transition metal oxides manufactured in the above examples and comparative examples, carbon black as a conductive material, and PVDF as a binder were mixed in an NMP solvent at a weight ratio of 95.0:2.0:3.0 to prepare a cathode slurry. The manufactured cathode slurry was applied to one surface of an aluminum current collector, dried at 130°C, and then rolled to manufacture a cathode. An electrode assembly was manufactured by interposing a porous polyethylene separator between the manufactured cathode and the lithium metal anode, and then positioned inside a battery case, and an electrolyte was injected into the case to manufacture a half cell. The electrolyte was prepared by dissolving 1.0 M LiPF6 in a mixed organic solvent containing ethylene carbonate: ethyl methyl carbonate: diethyl carbonate in a volume ratio of 3:4:3. (2) High temperature life evaluation For each half-cell manufactured in the above (1), an activation (formation) process was performed, and then the PNE-0506 charger / discharger (manufacturer: PNE Solution Co., Ltd.) was used to charge the battery under CC-CV conditions at 0.5C (reference capacity 1C = 200 mAh / g) at 45°C to 4.25 V, and CC discharged at 1.0C to 2.5 V. This charge / discharge cycle was considered as one cycle, and the initial discharge capacity was measured after one cycle, and then the discharge capacity was measured while repeating the same charge / discharge cycle for 50 cycles. Based on this, the capacity retention rate compared to the initial discharge capacity was calculated, and the results are shown in Fig. 2 and Table 2. (3) Gas generation evaluation For each half-cell manufactured in (1) above, an activation (formation) process was performed, and then the PNE-0506 charger / discharger (manufacturer: PNE Solution Co., Ltd.) was used to charge the battery under CC-CV conditions at 0.5C (standard capacity 1C = 200 mAh / g) at 45°C to 4.25 V, and CC discharged at 1.0C to 2.5 V. Afterwards, the battery was stored in a chamber at 60°C, and the half-cells were taken out of the chamber at weekly intervals and the volume change was calculated by applying the Archimedes principle using a hydrometer (MATSUHAKU, TWD-150DM). The results are shown in Fig. 3, and the gas generation per weight was calculated by dividing the volume change after 12 weeks by the weight of the cathode material, and the results are shown in Table 2 below. Capacity retention rate [%]Gas generation amount [mL / g]Example 191.70.206Comparative example 186.10.296Comparative example 289.60.263Comparative example 389.90.240 Through FIG. 2, FIG. 3 and Table 2, it can be confirmed that the cell to which the cathode material powder of Example 1 was applied showed superior evaluation results in terms of high-temperature life and high-temperature storage characteristics compared to the cell to which the cathode material powder of Comparative Examples 1 to 3 was applied.

Claims

1. Contains a lithium composite transition metal oxide containing nickel, cobalt, manganese and zirconium, A cathode material powder having a particle size distribution of 2.5 or more and 4.5 or less according to the following formula 1: [Formula 1] In the above equation 1, R i is the radius (㎛) of the i-th grain measured when the electrode manufactured by applying the above cathode material powder is subjected to ion milling treatment and then the electrode is analyzed by backscatter electron diffraction (EBSD). n is the total number of grains measured through the above EBSD analysis, which is 350 to 450.

2. In claim 1, A cathode material powder having a pellet density change of 2.5 or less according to the following formula 2 of the cathode material powder: [Formula 2] {(P 12ton -P 1.5ton ) / 10.5}×20 In the above equation 2, P 1.5ton The above cathode material powder is placed in a circular mold with a diameter of 13 mm and pressed with a force of 1,500 kgf to manufacture a pellet, and the pellet density (g / cc) is calculated by dividing the weight of the cathode material powder by the volume of the pellet. P 12ton The above cathode material powder is placed in a circular mold with a diameter of 13 mm and pressed with a force of 12,000 kgf to manufacture a pellet, and the pellet density (g / cc) is obtained by dividing the weight of the cathode material powder by the volume of the pellet.

3. In claim 1, A cathode material powder having a weight of zirconium of 300 ppm to 1,000 ppm based on the total weight of the lithium composite transition metal oxide.

4. In claim 1, D of the above cathode powder 50 This cathode material powder is 3㎛ to 6㎛.

5. In claim 1, A cathode material powder having a tap density of 1.8 g / cc to 2.3 g / cc.

6. In claim 1, A cathode material powder having an average grain diameter of 0.5 ㎛ to 4.0 ㎛.

7. In claim 1, A cathode material powder, wherein when the cathode material powder is placed in a circular mold with a diameter of 13 mm and pressurized with a force of 12,000 kgf, the rate of generation of fine particles having a particle diameter of 1 ㎛ or less is 2 vol% or less based on the total volume of the cathode material powder.

8. In claim 1, The above lithium composite transition metal oxide is a cathode material powder having a composition of the following chemical formula 1: [Chemical Formula 1] Li 1+x (Ni a Co b Mr c Zr d M1 e )O2 In the above chemical formula 1, M1 is at least one selected from the group consisting of Al, Ti, W, Mo, Nb, Cu, Fe, V, Cr, Zn, In, Ta, Y, La, Sr, Ga, Sc, Gd, Sm, Ca, Ce, Mg and B, x, a, b, c, d, and e are 0≤x≤0.50, 0.55≤a<1, 0, respectively. <b≤0.40, 0<c≤0.40, 0<d≤0.01, 0≤e≤0.10, a+b+c+d+e=1을 만족한다.

9. In claim 1, A cathode material powder having a nickel content of 70 mol% or more among metals other than lithium in the lithium composite transition metal oxide.

10. A first step of preparing a first mixture by mixing a transition metal-containing precursor including nickel, cobalt, and manganese with a lithium raw material; A second step of manufacturing a first sintered body by first firing the first mixture at 500°C to 900°C and second firing it at 700°C to 1,000°C; A third step of preparing a second mixture by mixing the first sintered body with a zirconium raw material; and A fourth step of producing a second sintered body in the form of single particles or pseudo-single particles by firing the second mixture a third time at 650°C to 900°C and a fourth time at 650°C to 950°C; and Including a fifth step of milling the second sintered body, A method for manufacturing a cathode material powder satisfying the following formula 3: [Formula 3] A≤0.95B In the above equation 3, A is D of the above transition metal-containing precursor 50 And, B is D of the above cathode powder 50 am.

11. In claim 10, A method for manufacturing a cathode material powder, wherein the milling of the fifth step is performed at a speed of 1,500 rpm to 3,000 rpm.

12. In claim 10, A method for manufacturing a cathode material powder, wherein B in the above formula 3 is 3㎛ to 6㎛.

13. A cathode comprising the cathode material powder of claim 1.

14. A lithium secondary battery comprising: a positive electrode according to claim 13; a negative electrode including a negative electrode active material; a separator interposed between the positive electrode and the negative electrode; and an electrolyte.

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