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CN-122010199-A - Copper-containing sodium ion battery positive electrode material precursor, preparation method thereof, sodium ion battery positive electrode material and sodium ion battery

CN122010199ACN 122010199 ACN122010199 ACN 122010199ACN-122010199-A

Abstract

The invention belongs to the field of sodium ion battery materials, and discloses a copper-containing sodium ion battery positive electrode material precursor which is of a core-shell structure and comprises an inner core and an outer shell coated on the surface of the inner core, wherein the inner core is nickel manganese iron hydroxide, the outer shell is copper hydroxide, and the tap density TD of the precursor is not lower than 1.40g/cm 3 . The invention also discloses a preparation method of the precursor of the sodium ion battery anode material, the sodium ion battery anode material and a sodium ion battery. The compaction density TD of the precursor of the nickel-iron-manganese-copper-sodium ion battery positive electrode material is not lower than 1.40g/cm 3 , the compaction density can be effectively increased by the high compaction density, so that the battery energy density is further enhanced, meanwhile, the compactness of particle arrangement can be increased by the high compaction density, so that the particle gap is reduced, the compaction density of the positive electrode material is improved, the energy volume density is further increased, a more compact structure can be brought by the high compaction density, the structural stability is enhanced, the particle breakage is reduced, and the material circulation performance is improved.

Inventors

  • ZHANG ZIXUAN
  • LV DONGLIANG
  • ZHU JIAN
  • ZHANG HAIYAN
  • HU ZHIBING
  • HU HAISHI
  • ZHANG JINJIN
  • LIU KAI
  • XIONG HAILONG
  • SU SHUAI
  • Lv Chenyan
  • LI HUIHAN
  • BAI LIXIONG

Assignees

  • 金驰能源材料有限公司
  • 湖南长远锂科新能源有限公司
  • 五矿新能源材料(湖南)股份有限公司

Dates

Publication Date
20260512
Application Date
20260116

Claims (12)

  1. 1. The precursor is of a core-shell structure and comprises an inner core and an outer shell coated on the surface of the inner core, wherein the inner core is nickel-manganese-iron hydroxide, the outer shell is copper hydroxide, the chemical formula of the precursor is Ni x Cu y Fe z Mn 1-x-y-z (OH) 2 , x is more than or equal to 0.1 and less than or equal to 0.4,0.04, y is more than or equal to 0.1,0.1 and z is more than or equal to 0.4, and the tap density TD of the precursor is not lower than 1.40g/cm 3 .
  2. 2. The positive electrode material precursor for sodium ion battery according to claim 1, wherein the secondary particles of the precursor are composed of flaky primary particles having a thickness of 50 to 150nm and a length of 1 to 2 μm.
  3. 3. The positive electrode material precursor for sodium ion battery according to claim 1, wherein the secondary particles of the precursor are spherical or spheroid, and the particle diameter D50 of the secondary particles is 3-5 μm.
  4. 4. The preparation method of the copper-containing sodium ion battery positive electrode material precursor is characterized by comprising the following steps of: (1) Dissolving a nickel source, an iron source and a manganese source in deionized water to prepare a nickel-iron-manganese salt mixed solution, and dissolving a copper source in deionized water to prepare a copper salt solution; (2) Adding reaction kettle bottom solution added with antioxidant B into a reaction kettle, then introducing inert gas into the reaction kettle to remove air in the reaction kettle, continuously adding nickel-iron-manganese salt mixed solution, alkali solution and ammonia water solution into the reaction kettle bottom solution under inert atmosphere, controlling pH to 9-12, performing coprecipitation reaction, and performing solid-liquid separation to obtain seed crystals; (3) Adding seed crystal into a reaction kettle again, adding deionized water to prepare a reaction kettle base solution, regulating the temperature of the base solution to be 30-40 ℃, and then adding copper salt solution and alkali solution into the base solution in parallel flow under the condition of not adding ammonia water or other complexing agents to react to obtain slurry; (4) And (3) aging, solid-liquid separation, washing and drying the slurry obtained in the step (3) to obtain a precursor of the nickel-iron-manganese-copper sodium ion battery anode material.
  5. 5. The process according to claim 4, wherein in the step (3), the reaction temperature is 30-40 ℃, the reaction time is 10-20 hours, the pH of the reaction process control system is 9.5-10.0, the stirring rate of the reaction kettle is 300-400r/min, the flow rate of the copper salt solution is 30-120mL/min, and the flow rate of the alkali solution is 10-80mL/h.
  6. 6. The preparation method of claim 4, wherein in the step (1), the molar concentration of the total metal salt in the ferronickel-manganese salt mixed solution is 1-4mol/L, the ferronickel-manganese salt mixed solution is further added with an antioxidant A, the concentration of the antioxidant A is 0.1-0.2g/L, and the antioxidant A comprises at least one of ascorbic acid, sodium citrate and citric acid.
  7. 7. The method according to claim 4, wherein in the step (2), the seed crystal has a D50 of 3 to 3.5. Mu.m.
  8. 8. The process according to claim 4, wherein in the step (2), the temperature of the reaction kettle bottom liquid is 40-60 ℃, the pH value is 11.0-11.5, the alkalinity is 3.0-9.0g/L, and the alkalinity is calculated as NH 4 + mol concentration; The temperature of the coprecipitation reaction is 40-60 ℃, the stirring speed is 400-600r/min, the flow of the ferronickel manganese salt mixed solution is 80-360mL/min, the flow of ammonia water is 10-60mL/min, the flow of alkali solution is 30-150mL/min, the pH is controlled at 11.0-11.5 in the first 30-40h of the coprecipitation reaction, the pH is controlled at 10.5-11.0 in the last 20-30h of the coprecipitation reaction.
  9. 9. The method according to claim 4, wherein in the step (2), the antioxidant B comprises at least one of hydrazine hydrate, sodium citrate, hydrazine and carbohydrazide, and the mass ratio of the pure water to the antioxidant B in the bottom solution of the reaction kettle is 1:0.001-0.004.
  10. 10. The method of claim 4, wherein the molar concentration of the copper salt solution is 0.5-2mol/L; The concentration of the ammonia water solution is 4-10mol/L; the alkali solution is sodium hydroxide solution with the concentration of 8-12 mol/L.
  11. 11. A positive electrode material for a sodium ion battery, characterized in that it is prepared from the positive electrode material precursor for a sodium ion battery according to any one of claims 1 to 3 or from the positive electrode material precursor for a sodium ion battery obtained by the preparation method according to any one of claims 4 to 10.
  12. 12. A sodium ion battery comprising the sodium ion battery positive electrode material of claim 11.

Description

Copper-containing sodium ion battery positive electrode material precursor, preparation method thereof, sodium ion battery positive electrode material and sodium ion battery Technical Field The invention belongs to sodium ion batteries, and particularly relates to a copper-containing sodium ion battery positive electrode material precursor, a preparation method thereof, a sodium ion battery positive electrode material and a sodium ion battery. Background The sodium ion battery is used as a new generation of electrochemical energy storage device, and has wide application prospect in the field of large-scale energy storage due to the advantages of abundant sodium resources, low cost, environmental friendliness and the like. Positive electrode materials are a key component in determining the performance of sodium ion batteries, where positive electrode materials based on transition metal oxides (e.g., layered oxides) are of interest due to their higher specific capacities and relatively sophisticated manufacturing processes. In recent years, in order to improve the electrochemical performance and stability of materials, researchers have been working on developing precursors of quaternary systems co-doped with multiple metals (e.g., nickel, iron, manganese, copper) in an effort to optimize the overall performance of the final positive electrode material through synergistic effects between the elements. In the preparation process of the quaternary precursor, the coprecipitation method is widely adopted because of the easy control of components and morphology. However, when elemental copper is introduced, the manufacturing process presents significant challenges due to its unique physicochemical properties. Copper ions (Cu 2+) are easy to form copper hydroxide (Cu (OH) 2) in an alkaline precipitation environment, and copper hydroxide has high solubility in a common complexing agent (such as ammonia water), so that segregation is easy to occur in the coprecipitation process, and uniform doping into a precursor crystal lattice is difficult. Such compositional non-uniformity can cause deterioration in the morphology of the precursor particles (e.g., rough surface, non-compact structure), thereby affecting the Tap Density (TD) and electrochemical properties of the final cathode material. There have been some attempts in the prior art to solve the above problems. For example, chinese patent application CN 117509752A discloses a copper-containing precursor and a preparation method thereof, wherein the precursor is prepared by preparing a copper salt solution and a salt solution containing nickel, iron and manganese, respectively, adding a chelating agent into the copper salt solution, and adopting a two-step precipitation process. Although the method relieves the segregation problem of copper to a certain extent, the method still has obvious defects that firstly, the primary particle size of the obtained precursor is thin, so that the stacking efficiency among particles is low, the tap density is undefined and possibly low, and secondly, a plurality of complexing agents are used in the process, so that the process complexity and the cost are increased. Another chinese patent application CN 118255400A describes a method for preparing nickel-iron-manganese-copper hydroxide precursors in stages by controlling the particle size by first preparing seed crystals and then growing. However, the technology adopts ferric salt as an iron source, which is easy to cause insufficient crystallinity of the precursor and loose structure, so that the tap density is lower. In summary, the existing nickel-iron-manganese-copper precursor preparation technology still has the common defects that (1) copper ions exist in a copper hydroxide form in a precursor, stable doping is difficult to occur due to easy dissolution in ammonia water, component segregation is easy to occur, and the precursor shape uniformity is poor, and (2) the prepared precursor has low tap density, so that the volume energy density and the processing performance of the final positive electrode material are limited. Therefore, developing a precursor capable of realizing uniform doping of copper element and simultaneously having high tap density and good morphology control and a preparation method thereof have become urgent demands for promoting the technical development of sodium ion batteries. Disclosure of Invention The invention aims to solve the technical problems and overcome the defects and shortcomings in the background art, and provides a copper-containing sodium ion battery positive electrode material precursor, a preparation method thereof, a sodium ion battery positive electrode material and a sodium ion battery. In order to solve the technical problems, the technical scheme provided by the invention is as follows: The precursor is a precursor of a copper-containing sodium ion battery positive electrode material with a copper-doped core-shell structure, is of a