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CN-121990545-A - Positive electrode material and preparation method thereof

CN121990545ACN 121990545 ACN121990545 ACN 121990545ACN-121990545-A

Abstract

The application relates to the technical field of sodium ion batteries, in particular to a positive electrode material and a preparation method thereof. The preparation method comprises the steps of mixing an X raw material and a Y raw material in a container filled with water, stirring to obtain slurry A, grinding the slurry A to obtain precursor slurry B, wherein the X raw material is a substance containing M element and not easy to dissolve in water, the Y raw material is sodium salt easy to dissolve in water, at least one of the X raw material and the Y raw material contains phosphorus element P, the spray drying step is to place the precursor slurry B in spray drying equipment for spray drying treatment to obtain precursor powder C, and the sintering step is to place the precursor powder C in sintering equipment for sintering treatment to obtain the positive electrode material. According to the application, the raw materials are specially designed in the mixing step, and the spray drying step and the sintering step are cooperated, so that the obtained positive electrode material product has high purity and good electrochemical performance.

Inventors

  • WANG GUOJING
  • YU JIUHONG
  • HE ZHIQI

Assignees

  • 微纳(宁波)电子材料有限公司

Dates

Publication Date
20260508
Application Date
20241104

Claims (10)

  1. 1. The preparation method of the positive electrode material has the molecular formula of Na 4 M 3-3a N 6a/m (PO 4 ) 2 P 2 O 7 , wherein M element is at least one of Mn, fe, ni and Co, N element is a doped metal element different from M element, the valence state of the N element is M, M is a natural number larger than 0, and a is more than or equal to 0 and less than or equal to 0.3, and the preparation method is characterized by comprising the following steps: Mixing, namely placing an X raw material and a Y raw material into a container containing water, mixing and stirring to obtain slurry A, and grinding the slurry A to obtain precursor slurry B, wherein the X raw material is a substance which contains M element and is not easy to dissolve in water, the Y raw material is sodium salt which is easy to dissolve in water, and at least one of the X raw material and the Y raw material contains phosphorus element P; a spray drying step, namely placing the precursor slurry B into spray drying equipment for spray drying treatment to obtain precursor powder C; and sintering, namely placing the precursor powder C into sintering equipment for sintering treatment to obtain the anode material.
  2. 2. The method for producing a positive electrode material according to claim 1, wherein, The average particle size of the X raw material ranges from 100 to 4000nm, and/or The particle diameter D50 of the X raw material ranges from 100 to 4000nm, and/or The particle diameter D10 of the X raw material ranges from 100 to 1500nm, and/or The particle size D90 of the X raw material ranges from 300 nm to 10000nm.
  3. 3. The method for producing a positive electrode material according to claim 1, wherein the X raw material has particle diameters D50, D10 and D90 satisfying D50/D10≤D90/D10.
  4. 4. The method for producing a positive electrode material according to claim 1, wherein the polydispersity index of the X raw material ranges from 0.1 to 0.7.
  5. 5. The method for producing a positive electrode material according to claim 1, wherein in the mixing step, the mass ratio of the X raw material to water in the container ranges from 15% to 80%, preferably from 15% to 75%, more preferably from 20% to 55%.
  6. 6. The method for preparing the cathode material according to claim 1, further comprising a precursor preparation step, wherein the precursor preparation step comprises the steps of introducing a solution S1 into a first inlet of a micro-reactor, wherein the solution S1 contains an element M, introducing a solution S2 into a second inlet of the micro-reactor, wherein the solution S2 contains a phosphorus element P, and mixing the solution S1 and the solution S2 through the micro-reactor to obtain a suspension, wherein the suspension is cured, centrifugally filtered and dried to obtain an X raw material.
  7. 7. The method according to claim 6, further comprising a PH adjuster for adjusting the PH of the solution S1 and/or the solution S2 and/or the suspension in the precursor preparation step.
  8. 8. The method for producing a positive electrode material according to claim 7, wherein, The pH of the solution S1 is in the range of 2.5-3.5, and/or The pH of the solution S2 is in the range of 7.0-11.0, and/or The pH range of the suspension is 3.0-7.0.
  9. 9. The method for producing a positive electrode material according to claim 7 or 8, characterized in that, When the pH adjustor is used for adjusting the solution S1, the pH adjustor is selected from at least one of hydrochloric acid, sulfuric acid or glacial acetic acid (CH 3 COOH), and/or When the pH adjustor is used for adjusting the solution S2, the pH adjustor is at least one selected from NaOH or ammonia water, preferably the pH adjustor is ammonia water, and/or When the pH adjustor is used to adjust the suspension, the pH adjustor is selected from at least one of H 3 PO 4 、NH 4 H 2 PO 4 、(NH 4 ) 2 HPO 4 、NaH 2 PO 4 or Na 2 HPO 4 .
  10. 10. A positive electrode material characterized by being produced according to the production method of any one of claims 1 to 9.

Description

Positive electrode material and preparation method thereof Technical Field The invention relates to the technical field of sodium ion batteries, in particular to a positive electrode material and a preparation method thereof. Background Sodium batteries are a hot spot for research of current new energy materials because of the advantages of rich resources, low cost, good low-temperature performance, high safety performance and the like. The preparation method of the sodium ion battery with high production efficiency, convenient industrialized production and excellent electrochemical performance is one of the problems to be solved in the battery industry at present. However, in the existing preparation method of the positive electrode material of the sodium ion battery, the solid-phase ball milling method has a plurality of impurity generation and the liquid-phase method has a complex process. Therefore, a method for preparing a positive electrode material of a sodium ion battery has yet to be improved. Disclosure of Invention The present application has been made in view of the above problems, and an object of the present application is to provide a positive electrode material and a method for producing the same, which can produce a positive electrode material having high purity and good electrochemical performance by the synergistic combination of a raw material design and a mixing step, a spray drying step, and a sintering step. The first aspect of the present application provides a method for preparing a positive electrode material, wherein the molecular formula of the positive electrode material is Na 4M3-3aN6a/m (PO4)2P2O7, wherein M is at least one selected from Mn, fe, ni, and Co, N is a doped metal element different from M, M is in a valence state of M, M is a natural number greater than 0, and a is greater than or equal to 0 and less than or equal to 0.3, and the method is characterized by comprising the steps of: the method comprises the steps of mixing an X raw material and a Y raw material in a container filled with water, stirring to obtain slurry A, and grinding the slurry A to obtain precursor slurry B, wherein the X raw material is a substance which contains M element and is not easy to dissolve in water, the Y raw material is sodium salt which is easy to dissolve in water, and at least one of the X raw material and the Y raw material contains phosphorus element P; A spray drying step, namely placing the precursor slurry B into spray drying equipment for spray drying treatment to obtain precursor powder C; and sintering, namely placing the precursor powder C into sintering equipment for sintering treatment to obtain the anode material. In any embodiment, the average particle size of the X starting material ranges from 100 to 4000nm. In any embodiment, the particle size D50 of the X starting material is in the range of 100-4000nm. In any embodiment, the particle size D10 of the X starting material is in the range of 100-1500nm. In any embodiment, the particle size D90 of the X starting material is in the range of 300-10000nm. In any embodiment, the particle sizes D50, D10 and D90 of the X raw material satisfy that D50/D10≤D90/D10. In any embodiment, the polydispersity index of the X starting material ranges from 0.1 to 0.7. In any embodiment, in the mixing step, the mass ratio of the X raw material to the water in the container ranges from 15% to 80%, preferably from 15% to 75%, more preferably from 20% to 55%. In any embodiment, the preparation method further comprises a precursor preparation step, wherein the precursor preparation step comprises the steps of introducing a solution S1 into a first inlet of a micro-reactor, wherein the solution S1 contains an element M, introducing a solution S2 into a second inlet of the micro-reactor, wherein the solution S2 contains a phosphorus element P, mixing the solution S1 and the solution S2 through the micro-reactor to obtain a suspension, and curing, centrifugally filtering and drying the suspension to obtain an X raw material. In any embodiment, in the precursor preparation step, a PH adjuster is further included, and the PH adjuster is used to adjust the PH value of the solution S1, and/or the solution S2, and/or the suspension. In any embodiment, the pH of solution S1 is in the range of 2.5 to 3.5. In any embodiment, when a PH adjuster is used to adjust the solution S1, the PH adjuster is selected from at least one of hydrochloric acid, sulfuric acid, or glacial acetic acid (CH 3 COOH). In any embodiment, the pH of solution S2 is in the range of 7.0 to 11.0. In any embodiment, when a pH adjustor is used to adjust the solution S2, the pH adjustor is selected from at least one of NaOH or ammonia, and preferably the pH adjustor is ammonia. In any embodiment, the pH of the suspension is in the range of 3.0 to 7.0. In any embodiment, when a PH adjuster is used to adjust the suspension, the PH adjuster is selected from at least one of H3PO4、NH4H2PO4、