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KR-20260063994-A - METHOD FOR PREPARING POSITIVE ELECTRODE ACTIVE MATERIAL

KR20260063994AKR 20260063994 AKR20260063994 AKR 20260063994AKR-20260063994-A

Abstract

A method for manufacturing a positive electrode active material is provided, comprising the step of mixing a calcined product of a positive electrode active material precursor with a dispersant and then grinding it, wherein the dispersant comprises a cellulose-based polymer, and wherein the method improves the flowability of particles during the grinding or classification process and prevents the adsorption of particles within the device. By applying such a manufacturing method, the time required for the entire process of the positive electrode active material can be shortened, thereby increasing the convenience and efficiency of the process.

Inventors

  • 최준호
  • 장영진
  • 이건석
  • 윤기열
  • 윤진영

Assignees

  • 주식회사 엘지화학

Dates

Publication Date
20260507
Application Date
20241031

Claims (15)

  1. The method includes the step of mixing the calcined product of the positive electrode active material precursor with a dispersant and then grinding it. The above-mentioned dispersant comprises a cellulose-based polymer, Method for manufacturing positive electrode active material.
  2. In claim 1, The calcined product of the above-mentioned positive electrode active material precursor is manufactured from a method comprising the step of mixing a transition metal raw material containing nickel and a lithium raw material and then calcining it. Method for manufacturing positive electrode active material.
  3. In claim 1, The above cellulose-based polymer comprises one or more selected from the group consisting of C1 to C10 ether-based side chains having cationic groups formed at the ends of each repeating unit, C1 to C10 ether-based side chains having hydroxyl groups formed at the ends, and combinations thereof. The above cationic group comprises a functional group in which a positive charge is formed on an element selected from the group consisting of N, O, P, S and combinations thereof, Method for manufacturing positive electrode active material.
  4. In claim 1, The above cellulose-based polymer has a nitrogen element content of 1% to 3% by weight based on the total weight of the polymer, Method for manufacturing positive electrode active material.
  5. In claim 1, The above cellulose-based polymer comprises at least one of the side chains represented by the following Chemical Formula 1 and Chemical Formula 2 in each repeating unit, Method for manufacturing positive electrode active material. [Chemical Formula 1] [Chemical Formula 2] In the above Chemical Formulas 1 and 2, Y1 and Y2 are the same or different from each other, and each is independently a single bond or a C1 to C4 alkyl group, and R1 to R10 are the same or different from each other, and each is independently hydrogen, a hydroxyl group or a C1 to C4 alkyl group, and Cat is a cationic group, and a and b are equal to or different from each other, and each is independently an integer from 1 to 4, and The above cationic group means that it includes a functional group in which a positive charge is formed on an element selected from the group consisting of N, O, P, S, and combinations thereof.
  6. In claim 1, The above dispersant is added in an amount greater than 0.3 parts by weight and less than 2.5 parts by weight based on 100 parts by weight of the above calcined product, Method for manufacturing positive electrode active material.
  7. In claim 1, The above cellulose-based polymer has a weight-average molecular weight (Mw) of 100,000 g/mol to 800,000 g/mol, Method for manufacturing positive electrode active material.
  8. In claim 1, The mixture of the above-mentioned calcined product and the dispersant is, (S1) A step of preparing a primary mixture by rotary mixing the above-mentioned calcined product and a dispersant; and (S2) A step of preparing a second mixture by grinding and mixing the first mixture; That which is performed including, Method for manufacturing positive electrode active material.
  9. In claim 1, The mixture of the above-mentioned calcined product and the dispersant has an avalanche energy of 5 mJ/kg to 40 mJ/kg, Method for manufacturing positive electrode active material.
  10. In claim 2, The above transition metal raw material is represented by the following formula 1, Method for manufacturing a positive electrode active material. [Equation 1] Ni c Co d M e (OH) 2 In the above Equation 1, M is selected from the group consisting of Mn, Al, and combinations thereof, and c, d, and e are 0<c<1, 0<d<1, and 0<e<1, respectively, and c+d+e=1.
  11. In claim 1, The above positive active material comprises a single particle, Method for manufacturing a positive electrode active material.
  12. In claim 2, The manufacture of the above-mentioned sintered product comprises: (1) a step of manufacturing a primary sintered product by sintering a mixture of the above-mentioned transition metal raw material and lithium raw material; (2) A step of crushing the primary calcined product; and (3) A step of manufacturing a secondary product by firing the above-mentioned crushed primary product; including, Method for manufacturing a positive electrode active material.
  13. In claim 12, The firing in step (1) above is performed at 600°C to 1,200°C for 2 to 20 hours, Method for manufacturing positive electrode active material.
  14. In claim 12, The firing in step (3) above is performed at 600°C to 1,200°C for 2 to 20 hours, Method for manufacturing positive electrode active material.
  15. In claim 1, The above manufacturing method, after the step of mixing the calcined product and the dispersant and then grinding, The method further includes the step of removing the above-mentioned dispersant, Method for manufacturing a positive electrode active material.

Description

Method for Preparing Positive Electrode Active Material The present invention relates to a method for manufacturing an anode active material. Specifically, the invention relates to a method for manufacturing an anode active material comprising the step of mixing a calcined product of an anode active material precursor with a dispersant and then grinding it, wherein the dispersant comprises a cellulose-based polymer. With the increasing technological development and demand for mobile devices, the demand for rechargeable batteries as an energy source is rapidly rising. Among these rechargeable batteries, lithium-ion batteries, which possess high energy density and voltage, long cycle life, and low self-discharge rates, have been commercialized and are widely used. Lithium transition metal oxides are used as cathode active materials for lithium secondary batteries, and among them, lithium cobalt composite metal oxides of LiCoO2 , which have high operating voltage and excellent capacity characteristics, have been mainly used. However, LiCoO2 has very poor thermal properties due to the descaling of its crystal structure following lithium delithiation, and because it is expensive, there are limitations to its mass use as a power source in fields such as electric vehicles. As materials to replace lithium cobalt composite metal oxides, lithium manganese composite metal oxides ( LiMnO2 or LiMn2O4 , etc.), lithium iron phosphate compounds ( LiFePO4, etc.), or lithium nickel composite metal oxides ( LiNiO2, etc.) have been developed. Among these, research on cathodes using high nickel (High Ni) cathode active materials, which have excellent capacity characteristics, has been actively conducted. Due to the low stability of the above-mentioned high-nickel cathode active materials, the development of single-particle high-nickel cathode active materials, which have superior structural and thermal stability compared to secondary particle forms, is being accelerated. However, these single-particle cathode active materials require a grinding or classification process within the manufacturing process. Generally, because the size of the single particles used in the grinding or classification process is small, the flowability is poor and adsorption occurs within the equipment, which increases the overall process time and results in poor yield, thereby reducing process efficiency. Accordingly, there is a need for a method to manufacture cathode active materials that can improve the efficiency of the entire process by preventing adsorption within the equipment while improving particle flowability during the grinding or classification process in the cathode active material manufacturing process. The present invention will be described in more detail below. Prior to this, terms and words used in this specification and claims should not be interpreted as being limited to their ordinary or dictionary meanings, but should be interpreted in a meaning and concept consistent with the technical spirit of the invention, based on the principle that the inventor can appropriately define the concept of the terms to best describe his invention. Accordingly, the configurations described in the embodiments described in this specification are merely one preferred embodiment of the invention and do not represent all of the technical spirit of the invention; therefore, it should be understood that various equivalents and modifications capable of replacing them may exist at the time of filing this application. In this specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. In this specification, "%" means weight percent unless otherwise explicitly indicated. In this specification, the term "substitution" means that a hydrogen atom bonded to a carbon atom of a compound is replaced with another substituent, and the substitution site is not limited to the site where the hydrogen atom is substituted, that is, any site where a substituent can be substituted. In addition, when two or more substitutions occur, the two or more substituents may be identical or different from each other. In this specification, "alkyl" means a straight-chain or branched-chain saturated hydrocarbon containing one radical, and the one radical determines the bonding position as a functional group, and the bonding position is not particularly limited. Examples of the term "alkyl" include, but are not limited to, methyl, ethyl, n-propyl, i-propyl, n-butyl, i-butyl, t-butyl, n-pentyl, i-pentyl, and hexyl. In this specification, "weight-average molecular weight (Mw)" refers to a converted value for standard polystyrene measured by gel permeation chromatography (GPC). Specifically, the weight-average molecular weight is a converted value obtained by measuring the value using GPC under the following conditions, and standard polystyrene