CN115259237A - Method for eliminating cobalt hydroxide micropowder - Google Patents
Method for eliminating cobalt hydroxide micropowder Download PDFInfo
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- CN115259237A CN115259237A CN202210762707.0A CN202210762707A CN115259237A CN 115259237 A CN115259237 A CN 115259237A CN 202210762707 A CN202210762707 A CN 202210762707A CN 115259237 A CN115259237 A CN 115259237A
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- solution
- cobalt
- flow rate
- cobalt hydroxide
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- 229910021503 Cobalt(II) hydroxide Inorganic materials 0.000 title claims abstract description 27
- ASKVAEGIVYSGNY-UHFFFAOYSA-L cobalt(ii) hydroxide Chemical compound [OH-].[OH-].[Co+2] ASKVAEGIVYSGNY-UHFFFAOYSA-L 0.000 title claims abstract description 27
- 238000000034 method Methods 0.000 title claims abstract description 20
- 239000000243 solution Substances 0.000 claims abstract description 60
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 15
- 238000003786 synthesis reaction Methods 0.000 claims abstract description 15
- 239000002994 raw material Substances 0.000 claims abstract description 11
- 230000015572 biosynthetic process Effects 0.000 claims abstract description 10
- 150000001868 cobalt Chemical class 0.000 claims abstract description 9
- 238000003756 stirring Methods 0.000 claims abstract description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000001035 drying Methods 0.000 claims abstract description 8
- 238000005406 washing Methods 0.000 claims abstract description 8
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims abstract description 5
- 235000011114 ammonium hydroxide Nutrition 0.000 claims abstract description 5
- 239000007853 buffer solution Substances 0.000 claims abstract description 5
- 229910017052 cobalt Inorganic materials 0.000 claims abstract description 5
- 239000010941 cobalt Substances 0.000 claims abstract description 5
- GUTLYIVDDKVIGB-UHFFFAOYSA-N cobalt atom Chemical compound [Co] GUTLYIVDDKVIGB-UHFFFAOYSA-N 0.000 claims abstract description 5
- 238000001914 filtration Methods 0.000 claims abstract description 5
- 230000000087 stabilizing effect Effects 0.000 claims abstract description 5
- 239000000843 powder Substances 0.000 claims abstract description 4
- 239000002002 slurry Substances 0.000 claims description 5
- NWZSZGALRFJKBT-KNIFDHDWSA-N (2s)-2,6-diaminohexanoic acid;(2s)-2-hydroxybutanedioic acid Chemical compound OC(=O)[C@@H](O)CC(O)=O.NCCCC[C@H](N)C(O)=O NWZSZGALRFJKBT-KNIFDHDWSA-N 0.000 claims description 4
- 239000000654 additive Substances 0.000 claims description 4
- 230000000996 additive effect Effects 0.000 claims description 4
- GVPFVAHMJGGAJG-UHFFFAOYSA-L cobalt dichloride Chemical compound [Cl-].[Cl-].[Co+2] GVPFVAHMJGGAJG-UHFFFAOYSA-L 0.000 claims description 4
- UFMZWBIQTDUYBN-UHFFFAOYSA-N cobalt dinitrate Chemical group [Co+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O UFMZWBIQTDUYBN-UHFFFAOYSA-N 0.000 claims description 4
- 229910001981 cobalt nitrate Inorganic materials 0.000 claims description 4
- 239000008367 deionised water Substances 0.000 claims description 4
- 229910021641 deionized water Inorganic materials 0.000 claims description 4
- IKDUDTNKRLTJSI-UHFFFAOYSA-N hydrazine monohydrate Substances O.NN IKDUDTNKRLTJSI-UHFFFAOYSA-N 0.000 claims description 4
- 230000002194 synthesizing effect Effects 0.000 claims description 4
- 238000002360 preparation method Methods 0.000 abstract description 7
- 239000002245 particle Substances 0.000 abstract description 6
- 239000010405 anode material Substances 0.000 abstract description 4
- HBBGRARXTFLTSG-UHFFFAOYSA-N Lithium ion Chemical compound [Li+] HBBGRARXTFLTSG-UHFFFAOYSA-N 0.000 description 3
- 229910001416 lithium ion Inorganic materials 0.000 description 3
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 2
- UBEWDCMIDFGDOO-UHFFFAOYSA-N cobalt(2+);cobalt(3+);oxygen(2-) Chemical compound [O-2].[O-2].[O-2].[O-2].[Co+2].[Co+3].[Co+3] UBEWDCMIDFGDOO-UHFFFAOYSA-N 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 229910052744 lithium Inorganic materials 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005056 compaction Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G51/00—Compounds of cobalt
- C01G51/04—Oxides; Hydroxides
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/01—Particle morphology depicted by an image
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/51—Particles with a specific particle size distribution
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
Abstract
The invention discloses a method for eliminating cobalt hydroxide micropowder, which comprises the following steps: 1. preparing a solution: preparing a solution A with the cobalt concentration of 110-120g/L by taking cobalt salt as a raw material, preparing a solution B with the concentration of 250-300g/L by taking sodium hydroxide as a raw material, adding 0.04-0.06 time of ammonia water solution with the volume of 180-200g/L into the solution B, and storing the prepared solution for later use; 2. and (3) synthesis reaction: adding hot pure water with a fixed volume into each kettle as a synthesis buffer solution, controlling the temperature, stirring, then sequentially adding the solution A and the solution B, adjusting the flow rate of the solution A by stages, controlling the pH =7.4-8.4, and stabilizing the flow rate of the solution B; 3. filtering, washing and drying. The invention aims at the problems that the existing cobalt hydroxide preparation process has high small particle (micro powder) occupation ratio, has large influence on the subsequent preparation of anode materials, generally has large Dmax and has poor product appearance.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a method for eliminating cobalt hydroxide micropowder.
Background
The lithium ion battery prepared by taking lithium cobaltate as the anode material has the characteristics of light weight, large capacity, high specific energy, high working voltage, stable discharge, suitability for heavy-current discharge, good cycle performance, long service life and the like, and is mainly applied to the field of 3C digital codes.
Lithium cobaltate is developing towards high voltage, high compaction and high cycle performance, cobalt hydroxide is used as a precursor of cobaltosic oxide, and the performance of cobalt hydroxide directly influences the preparation of a subsequent lithium ion battery anode material, so that the requirement on the cobalt hydroxide as a raw material is higher and higher.
The existing cobalt hydroxide preparation process has the following problems:
1. the small particles (micro powder) have higher proportion, and have larger influence on the subsequent preparation of the anode material;
2. dmax is generally large;
the product appearance is poor.
Disclosure of Invention
Aiming at the technical problems, the invention provides a method for eliminating cobalt hydroxide micropowder.
In order to achieve the above purpose, the technical scheme of the invention is as follows:
a method for eliminating cobalt hydroxide micropowder comprises the following steps:
1. preparing a solution:
preparing a solution A with the cobalt concentration of 110-120g/L by using cobalt salt as a raw material, preparing a solution B with the concentration of 250-300g/L by using sodium hydroxide as a raw material, adding 0.04-0.06 time of ammonia water solution with the volume of 180-200g/L into the solution B, adding 5-8L of hydrazine hydrate serving as an additive, and storing the prepared solution for later use;
2. and (3) synthesis reaction:
adding hot pure water with a fixed volume into each kettle as a synthesis buffer solution, controlling the temperature and stirring, then sequentially adding solution A and solution B, adjusting the flow rate of the solution A by stages, controlling the pH =7.4-8.4, stabilizing the flow rate of the solution B, synthesizing for 18-20 hours, detecting the granularity, and performing subsequent processes when the granularity reaches the required index;
3. filtering, washing and drying:
after the synthesis is finished, centrifugally washing the slurry with deionized water at the temperature of 80-100 ℃, and drying at the temperature of 100-120 ℃ to obtain a cobalt hydroxide product;
wherein, in the first step, the cobalt salt is cobalt nitrate or cobalt chloride.
Wherein, in the second step, the flow rate of the solution B is 200-500L/h.
In the second step, the step of adjusting the flow rate of the solution A in stages comprises the following steps: 1-10h:450-500L/h, after 10h: 200-300L/h.
Wherein in the second step, the temperature is controlled to be 74-76 ℃, and the stirring speed is 35HZ.
The invention has the beneficial effects that:
1. the synthesis adopts high-concentration solution, and the feeding is carried out at a large flow rate, so that the production efficiency is greatly improved;
2. the growth speed is controlled through the stage adjustment of the process flow, the product appearance is improved, and the output of micro powder is avoided;
3. the cobalt hydroxide product prepared by the method has better particle size distribution, taking the medium particle size as an example: dmin is more than or equal to 2um, D10 is more than or equal to 5-7um, D50 is more than or equal to 7.5-9.5um, dmax is less than or equal to 35um, (D90-D10)/D50 is less than or equal to 75 percent.
Drawings
FIG. 1 is a morphology chart of a medium-granularity cobalt hydroxide product synthesized by the preparation method of the invention;
FIG. 2 is a morphology chart of a large-particle-size cobalt hydroxide product synthesized by the preparation method of the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to the accompanying drawings in conjunction with the following detailed description. It is to be understood that these descriptions are only illustrative and are not intended to limit the scope of the present invention. Moreover, in the following description, descriptions of well-known structures and techniques are omitted so as to not unnecessarily obscure the concepts of the present invention.
Example 1
A method for eliminating cobalt hydroxide micropowder comprises the following steps:
1. preparing a solution:
preparing a solution A with the cobalt concentration of 110g/L by taking cobalt salt as a raw material, preparing a solution B with the concentration of 250g/L by taking sodium hydroxide as a raw material, adding 0.04 times of ammonia water solution with the volume and the concentration of 180g/L into the solution B, adding 5L of hydrazine hydrate serving as an additive, and storing the prepared solution for later use;
2. and (3) synthesis reaction:
adding hot pure water with a fixed volume into each kettle as a synthesis buffer solution, controlling the temperature and stirring, then sequentially adding solution A and solution B, adjusting the flow rate of the solution A by stages, controlling the pH =7.4, stabilizing the flow rate of the solution B, synthesizing for 18 hours, detecting the granularity, and performing subsequent processes when the granularity reaches the required index;
3. filtering, washing and drying:
after the synthesis is finished, centrifugally washing the slurry by using deionized water at 80 ℃ and drying the slurry at 100 ℃ to obtain a cobalt hydroxide product;
wherein, in the first step, the cobalt salt is cobalt nitrate or cobalt chloride.
In the second step, the flow rate of the solution B is 200L/h.
In the second step, the step of adjusting the flow rate of the solution A in stages comprises the following steps: 1-10h:450L/h, after 10h: 200L/h.
In the second step, the temperature is controlled at 74 ℃, and the stirring speed is 35HZ.
The following table is a product particle size distribution table:
FIG. 1 is a morphology chart of a medium-sized cobalt hydroxide product synthesized by the present invention.
FIG. 2 is a morphology chart of a large particle size cobalt hydroxide product synthesized by the present invention.
Example 2
A method for eliminating cobalt hydroxide micropowder comprises the following steps:
1. preparing a solution:
preparing a solution A with the cobalt concentration of 120g/L by taking cobalt salt as a raw material, preparing a solution B with the concentration of 300g/L by taking sodium hydroxide as a raw material, adding 0.06-time volume of ammonia water solution with the concentration of 200g/L into the solution B, adding 8L of hydrazine hydrate serving as an additive, and storing the prepared solution for later use;
2. and (3) synthesis reaction:
adding hot pure water with a fixed volume into each kettle as a synthesis buffer solution, controlling the temperature and stirring, then sequentially adding solution A and solution B, adjusting the flow rate of the solution A by stages, controlling the pH =8.4, stabilizing the flow rate of the solution B, synthesizing for 20 hours, detecting the granularity, and performing subsequent processes when the granularity reaches the required index;
3. filtering, washing and drying:
after the synthesis is finished, centrifugally washing the slurry with deionized water at 100 ℃, and drying at 120 ℃ to obtain a cobalt hydroxide product;
wherein, in the first step, the cobalt salt is cobalt nitrate or cobalt chloride.
In the second step, the flow rate of the solution B is 500L/h.
In the second step, the step of adjusting the flow rate of the solution A in stages comprises the following steps: 1-10h: 500L/h, after 10h: 300L/h.
In the second step, the temperature is controlled at 76 ℃, and the stirring speed is 35HZ.
It should be understood that the above-described embodiments of the present invention are merely illustrative of or explaining the principles of the invention and are not to be construed as limiting the invention. Therefore, any modification, equivalent replacement, improvement and the like made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention. Further, it is intended that the appended claims cover all such variations and modifications as fall within the scope and boundaries of the appended claims or the equivalents of such scope and boundaries.
Claims (5)
1. The method for eliminating the cobalt hydroxide micropowder is characterized by comprising the following steps:
1. preparing a solution:
preparing a solution A with the cobalt concentration of 110-120g/L by taking cobalt salt as a raw material, preparing a solution B with the concentration of 250-300g/L by taking sodium hydroxide as a raw material, adding 0.04-0.06 time of ammonia water solution with the volume of 180-200g/L and 5-8L of additive hydrazine hydrate into the solution B, and storing the prepared solution for later use;
2. and (3) synthesis reaction:
adding hot pure water with a fixed volume into each kettle as a synthesis buffer solution, controlling the temperature and stirring, then sequentially adding solution A and solution B, adjusting the flow rate of the solution A by stages, controlling the pH =7.4-8.4, stabilizing the flow rate of the solution B, synthesizing for 18-20 hours, detecting the granularity, and performing subsequent processes when the granularity reaches the required index;
3. filtering, washing and drying:
after the synthesis is finished, the slurry is centrifugally washed by deionized water at the temperature of 80-100 ℃ and dried at the temperature of 100-120 ℃ to obtain a cobalt hydroxide product.
2. The method for eliminating the cobalt hydroxide micropowder according to claim 1, wherein in the first step, the cobalt salt is cobalt nitrate or cobalt chloride.
3. The method for eliminating the cobalt hydroxide micropowder according to claim 1, wherein in the second step, the flow rate of the solution B is 200-500L/h.
4. The method for removing fine cobalt hydroxide powder according to claim 3, wherein in the second step, the flow rate of the solution A is adjusted in stages as follows: 1-10h:450-500L/h, after 10h: 200-300L/h.
5. The method for eliminating the cobalt hydroxide micropowder according to claim 1, wherein in the second step, the temperature is controlled to be 74-76 ℃, and the stirring speed is 35Hz.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210762707.0A CN115259237A (en) | 2022-06-30 | 2022-06-30 | Method for eliminating cobalt hydroxide micropowder |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210762707.0A CN115259237A (en) | 2022-06-30 | 2022-06-30 | Method for eliminating cobalt hydroxide micropowder |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105439212A (en) * | 2014-09-30 | 2016-03-30 | 荆门市格林美新材料有限公司 | Preparation method for cell grade cobalt hydroxide |
| CN110342587A (en) * | 2019-04-23 | 2019-10-18 | 金川集团股份有限公司 | A kind of big granularity cobaltosic oxide preparation method of narrow ditribution |
| CN112320855A (en) * | 2020-11-11 | 2021-02-05 | 金川集团股份有限公司 | Preparation method of medium-granularity cobaltosic oxide |
| CN113735185A (en) * | 2021-08-25 | 2021-12-03 | 金川集团股份有限公司 | Preparation method of narrow-distribution medium-particle-size cobaltosic oxide |
| CN113735182A (en) * | 2021-08-25 | 2021-12-03 | 金川集团股份有限公司 | Preparation method of large-particle-size aluminum-coated cobaltosic oxide |
-
2022
- 2022-06-30 CN CN202210762707.0A patent/CN115259237A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105439212A (en) * | 2014-09-30 | 2016-03-30 | 荆门市格林美新材料有限公司 | Preparation method for cell grade cobalt hydroxide |
| CN110342587A (en) * | 2019-04-23 | 2019-10-18 | 金川集团股份有限公司 | A kind of big granularity cobaltosic oxide preparation method of narrow ditribution |
| CN112320855A (en) * | 2020-11-11 | 2021-02-05 | 金川集团股份有限公司 | Preparation method of medium-granularity cobaltosic oxide |
| CN113735185A (en) * | 2021-08-25 | 2021-12-03 | 金川集团股份有限公司 | Preparation method of narrow-distribution medium-particle-size cobaltosic oxide |
| CN113735182A (en) * | 2021-08-25 | 2021-12-03 | 金川集团股份有限公司 | Preparation method of large-particle-size aluminum-coated cobaltosic oxide |
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Effective date of registration: 20240429 Address after: 737104 No. 2 Lanzhou Road, Beijing Road Street, Jinchuan District, Jinchang City, Gansu Province Applicant after: Jinchuan Group Nickel Cobalt Co.,Ltd. Country or region after: China Applicant after: LANZHOU JINCHUAN ADVANGCED MATERIALS TECHNOLOGY Co.,Ltd. Address before: 737103 No. 98, Jinchuan Road, Jinchang, Gansu Applicant before: JINCHUAN GROUP Co.,Ltd. Country or region before: China Applicant before: LANZHOU JINCHUAN ADVANGCED MATERIALS TECHNOLOGY Co.,Ltd. |