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CN-121496546-B - Single crystal nickel cobalt manganese positive electrode material, preparation method, positive electrode plate and lithium ion battery

CN121496546BCN 121496546 BCN121496546 BCN 121496546BCN-121496546-B

Abstract

The invention provides a monocrystal nickel cobalt manganese positive electrode material, a preparation method, a positive electrode plate and a lithium ion battery. The preparation method comprises the steps of mixing a nickel cobalt manganese precursor, a lithium source and a first auxiliary agent, performing first sintering to obtain a first sintering material, mixing the first sintering material and a second auxiliary agent, performing second sintering to obtain a second sintering material, mixing the second sintering material and a third auxiliary agent, and performing third sintering to obtain the monocrystal nickel cobalt manganese positive electrode material, wherein the half-peak width a of a crystal face of the nickel cobalt manganese precursor (001) and the half-peak width b of a crystal face of the nickel cobalt manganese precursor (100) meet that a is more than or equal to 0.30 and less than or equal to 0.48,0.38 and b is more than or equal to 0.52,1.1 and b/a is more than or equal to 1.5. The method combines the roundness of the monocrystal nickel cobalt manganese positive electrode material with the half-peak width of the nickel cobalt manganese precursor, quantifies the half-peak width, screens the nickel cobalt manganese precursor, and combines a three-time sintering system to prepare the monocrystal nickel cobalt manganese positive electrode material with high roundness and good structure stability.

Inventors

  • ZHAO JUNJUN
  • QI WANG
  • ZHOU ZHIYUAN
  • KE CHANGXUAN
  • LI WENQIANG
  • ZHU WU

Assignees

  • 天津国安盟固利新材料科技股份有限公司

Dates

Publication Date
20260508
Application Date
20260114

Claims (5)

  1. 1. The preparation method of the monocrystal nickel cobalt manganese positive electrode material is characterized by comprising the following steps of: mixing a nickel cobalt manganese precursor, a lithium source and a first auxiliary agent, and performing first sintering to obtain a first sintering material, mixing the first sintering material with a second auxiliary agent, performing second sintering to obtain a second sintering material, mixing the second sintering material with a third auxiliary agent, and performing third sintering to obtain the monocrystal nickel cobalt manganese anode material; The half-peak width a of the (001) crystal face and the half-peak width b of the (100) crystal face of the nickel cobalt manganese precursor are satisfied that a is more than or equal to 0.30 and less than or equal to 0.48,0.38 and b is more than or equal to 0.52,1.1 and b/a is more than or equal to 1.5; The first auxiliary agent is ZrO 2 ; The second auxiliary agent is Co (OH) 2 ; The third auxiliary agent is Al 2 O 3 ; The first sintering comprises sintering at a first temperature platform and a second temperature platform in sequence, wherein the temperature of the first temperature platform is 40-90 ℃ lower than that of the second temperature platform, the temperature of the second sintering is 100-200 ℃ lower than that of the second temperature platform, the temperature of the third sintering is 300-600 ℃ lower than that of the second temperature platform, and the temperature of the second temperature platform is 800-1000 ℃.
  2. 2. The method of claim 1, wherein the sintering is performed at the first temperature stage for 5-12 hours; And/or sintering at the second temperature platform for 8-12 h.
  3. 3. The method of claim 1, wherein the second sintering time is 8h to 15h.
  4. 4. The method of claim 1, wherein the third sintering time is 6h to 12h.
  5. 5. The preparation method of claim 1, wherein the addition amount of the first auxiliary agent is 0.3-1.5 wt.% of the mass of the nickel-cobalt-manganese precursor; and/or the addition amount of the second auxiliary agent is 1-3 wt% of the mass of the first sintering material; And/or the addition amount of the third auxiliary agent is 0.1wt.% to 0.5wt.% of the mass of the second sintering material.

Description

Single crystal nickel cobalt manganese positive electrode material, preparation method, positive electrode plate and lithium ion battery Technical Field The invention relates to the technical field of lithium ion batteries, in particular to a positive electrode material, and especially relates to a monocrystal nickel cobalt manganese positive electrode material, a preparation method, a positive electrode plate and a lithium ion battery. Background Currently, nickel-cobalt-manganese ternary cathode materials (NCMs) have become the mainstream choice for new energy automobile power batteries by virtue of their excellent comprehensive properties. Along with the rapid iteration of the new energy automobile industry, the performance requirements of the market on the power battery are more severe, which directly promotes the breakthrough of the ternary positive electrode material to the directions of high capacity and high stability, and the monocrystal nickel cobalt manganese positive electrode material becomes the key field of current research and development and application due to the unique advantages. However, the monocrystal nickel-cobalt-manganese cathode material produced by the prior art still exists in a similar monocrystal or a mixture of similar monocrystal and monocrystal, and the high-purity nickel-cobalt-manganese ternary cathode material is still difficult to prepare. CN111600015A discloses a narrow-distribution small-granularity spherical nickel cobalt manganese hydroxide precursor material and a preparation method thereof, the prepared spherical nickel cobalt manganese hydroxide precursor has good dispersibility, unique morphology, high compaction density and concentrated diameter distance distribution, d50=2-3 μm of the precursor and laminated lath vertical insertion-shaped primary particles with the diameter distance distribution of 0.7-1.0, the laminated thickness of the primary particles is 2-200 nm, the length of the primary particles is 40-1000 nm, and the preparation method is simple and convenient to operate, is integrated with nucleation, crystallization and growth, and meets the requirements of industrial production. CN106602055A discloses a small-particle monocrystal lithium nickel cobalt manganese oxide positive electrode material and a preparation method thereof, and a spray drying method is adopted to enable precursor fragments to be assembled into a sphere so as to achieve the purpose that a metal additive is embedded into the sphere, so that the problem that the metal additive only coats the surface of the precursor in dry mixing and cannot enter the precursor is solved, the particle size of the prepared small-particle monocrystal lithium nickel cobalt manganese oxide positive electrode material is small and uniform, and the structural stability of the positive electrode material is improved. CN109786672a discloses a preparation method of a micron-sized monocrystal ternary cathode material, which comprises the steps of grinding nickel carbonyl, cobalt carbonyl, manganese carbonyl and tertiary butyl lithium in a sand mill at a high speed according to a molar ratio, and then sintering in an air atmosphere to obtain the micron-sized monocrystal ternary cathode material. The micron-sized monocrystal ternary cathode material synthesized by the process has the advantages of low specific surface area, concentrated particle size distribution, high thermal stability and the like, and in addition, the material has lower specific surface area, lower contact degree with electrolyte, and longer cycle life compared with the conventional spherical agglomerated material. Therefore, the nickel-cobalt-manganese ternary positive electrode material with high single crystallization degree and good structural stability is provided. Disclosure of Invention Aiming at the defects existing in the prior art, the invention aims to provide a monocrystal nickel cobalt manganese positive electrode material, a preparation method, a positive electrode plate and a lithium ion battery. According to the preparation method, the roundness of the monocrystal nickel cobalt manganese positive electrode material is combined with the XRD characteristic peak half-peak width of the nickel cobalt manganese precursor, quantification is carried out, the nickel cobalt manganese precursor is screened, meanwhile, a three-time sintering system is combined, and auxiliary agents are respectively added in the three-time sintering system for doping and/or cladding, so that the monocrystal nickel cobalt manganese positive electrode material with high roundness and stable structure is prepared, and the thermodynamic stability, the circulation performance and the high-temperature storage performance of the monocrystal nickel cobalt manganese positive electrode material are improved. In order to achieve the aim of the invention, the invention adopts the following technical scheme: The invention provides a preparation method of a monocrysta