CN114057239B - Preparation method of alkaline-water-washed high-nickel ternary precursor - Google Patents
Preparation method of alkaline-water-washed high-nickel ternary precursor Download PDFInfo
- Publication number
- CN114057239B CN114057239B CN202111539872.1A CN202111539872A CN114057239B CN 114057239 B CN114057239 B CN 114057239B CN 202111539872 A CN202111539872 A CN 202111539872A CN 114057239 B CN114057239 B CN 114057239B
- Authority
- CN
- China
- Prior art keywords
- reaction
- precursor
- nickel
- preparation
- water
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01G—COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSES C01D OR C01F
- C01G53/00—Compounds of nickel
- C01G53/006—Compounds containing, besides nickel, two or more other elements, with the exception of oxygen or hydrogen
-
- 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
- C01P2004/03—Particle morphology depicted by an image obtained by SEM
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/11—Powder tap density
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/40—Electric properties
-
- 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
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Manufacture Of Metal Powder And Suspensions Thereof (AREA)
- Inorganic Compounds Of Heavy Metals (AREA)
- Battery Electrode And Active Subsutance (AREA)
Abstract
The invention provides a preparation method of a high-nickel ternary precursor with high tap density, narrow particle size distribution and good spherical morphology for the first time. The method adopts high-concentration ammonia water, high-concentration NaOH solution and high-nickel metal salt solution to carry out coprecipitation reaction, thereby not only promoting production efficiency by increasing the solid content of slurry in a reaction system, but also enabling precursor particles to collide and rub with each other in high-solid-content feed liquid to obtain a product with uniform size, compact particle morphology and high sphericity; in addition, the high-nickel precursor is crystallized and grown under the alkaline condition of higher pH, so that the coprecipitation precursor particles are washed and filtered by adopting an alkaline washing-water washing process, the precursor particles are protected from being destroyed due to the reverse dissolution of single water washing, and the size distribution of the precursor particles is narrow and the tap density is higher under the same condition. Compared with the traditional process for preparing the ternary precursor by coprecipitation, the method has the advantages of higher production efficiency, more controllable product particle morphology and remarkably improved cycle performance of the obtained product.
Description
Technical Field
The invention relates to the technical field of lithium battery high-nickel precursors and positive electrode materials, in particular to a preparation method of a high-nickel ternary precursor washed by alkaline water.
Background
Along with the rapid development of new energy automobile industry in China, power lithium ionThe sub-battery has wide application market as a main energy source. In two large positive electrode material systems of power lithium ion batteries, conventional lithium iron phosphate (LiFePO 4 ) And low nickel ternary material (LiNi x Co y Mn 1-x-y (OH) 2 ，x<0.6 Because of the limited energy density (150-160 Wh/kg), the requirements of the electric automobile on the endurance mileage are difficult to meet, while the high nickel ternary material (LiNi x Co y Mn 1-x-y (OH) 2 X.gtoreq.0.6) due to Ni 2+ /Ni 4+ The pair of electricity can provide more reversible capacity (the energy density can reach 300 Wh/kg), so the development and industrialization of high-energy-density high-nickel ternary materials are the development trend of current and future power batteries.
The preparation process of the high-nickel ternary material is the same as that of the common ternary material, and a coprecipitation method is generally adopted in industry to prepare a nickel cobalt manganese hydroxide precursor with higher tap density firstly, and then the precursor and a lithium source are mixed and sintered to prepare the positive electrode material. The preparation method comprises the steps of preparing a precursor, namely, preparing a high-nickel precursor, wherein each property of the positive electrode material is greatly dependent on the physicochemical properties of the precursor, the technical content of the precursor preparation accounts for more than 60% of the technical content of the whole ternary material, the coprecipitation reaction of the high-nickel precursor is also required to be carried out under the condition of higher pH along with the improvement of the Ni content in the high-nickel material, the higher the solid content in a certain range in the reaction process is, the more frequent the precursor particles collide in the stirring process of a feed liquid, the better the particle morphology, size and compactness of the product are, and the higher the tap density of the final material is, so that the improvement of the morphology and the tap density of the precursor is a key for increasing the solid content of the reaction feed liquid in a reaction kettle with a certain volume; meanwhile, the precursor precipitate is required to be washed after the reaction is finished, the pH value of the coprecipitation reaction of the high-nickel precursor is usually required to be controlled to be more than 11.0, which means that precursor particles are grown in a feed liquid with higher alkalinity, the precursor particles are directly washed for a plurality of times by deionized water, then filtered and dried in a traditional washing mode, and the precursor particles are easily reversely dissolved on the surface components of the precursor particles to damage the morphology due to rightward movement of the precipitation-dissolution balance, and the tap density is reduced due to the fact that the particle size is reduced to some extent, so that impurity ions mixed in the precursor precipitate are completely washed, and the phenomenon of reversely dissolving the precursor in the washing process is avoided as much as possible.
Disclosure of Invention
The invention provides a preparation method of a high-nickel ternary precursor with high tap density, narrow particle size distribution and high sphericity for the first time.
In order to improve the solid content of slurry in the coprecipitation reaction process of the high nickel precursor, under the condition of a certain concentration of a metal salt solution, a high-concentration ammonia water complexing agent and a sodium hydroxide precipitant are adopted, and NH in the feeding process is maintained by the feeding speed of small ammonia water and alkali liquor 3 : the TM ratio and the reaction pH are certain, so that a spherical high-nickel ternary precursor with excellent morphology and high tap density is prepared; in order to avoid the damage of particle morphology and size shrinkage caused by reverse dissolution in the process of washing precursor sediment, the invention adopts alkaline water with pH close to that of reaction slurry to wash the sediment, and finally uses pure water to wash a small amount of impurity ions remained in the sediment. In order to achieve the above object, the following technical scheme is adopted:
the invention relates to a preparation method of a high-nickel ternary precursor washed by alkaline water; comprises the following steps of;
(1) Preparing various reaction raw material liquid;
the preparation of each reaction raw material liquid comprises the following steps: preparing a high nickel metal salt solution I, preparing an ammonia water complexing agent II, preparing an alkali solution precipitant III, and preparing ammonia water with a certain concentration as a reaction base solution IV before reaction feeding;
the preparation of the high nickel metal salt solution I comprises the following steps: accurately weighing soluble metal salts of nickel, cobalt and manganese according to the element design proportion of Ni, co and Mn in the material, placing the material in a storage tank, and adding hot water at 40-50 ℃ for rapid dissolution to ensure that the total concentration of metals in Ni, co and Mn solutions is 1.5-2.5mol/L;
the preparation of the alkali liquor precipitant III comprises the following steps: the concentration range of the alkali liquor is 6.0-10.0mol/L;
the preparation of the ammonia water complexing agent II comprises the following steps: the concentration range of the ammonia water is as follows: 4.4 to 6.0mol/L
The preparation of the reaction base solution IV comprises the following steps: the concentration range of the ammonia water is 1.1-1.5mol/L, and the volume of the base solution accounts for 1/3-1/2 of the volume of the reaction kettle;
(2) Preparation of high nickel precursor Ni by nickel cobalt manganese coprecipitation reaction x Co y Mn 1-x-y (OH) 2 ；
Wherein x is more than or equal to 0.6 and less than 1, y is more than or equal to 0 and less than 0.4, and x+y is more than or equal to 1;
pouring pure water required in the reaction base solution IV into a reaction kettle before reaction in the step (2), pumping circulating water into an interlayer of the reaction kettle through a water bath kettle to heat the reaction kettle, continuously introducing nitrogen into the kettle to exhaust air, adding a certain amount of concentrated ammonia water required in the base solution into the kettle through a feed inlet after the temperature in the kettle is raised to a set temperature, firstly starting an alkaline pump to add alkaline solution to raise the pH value of the base solution to a reaction set value A, then pumping a high-nickel metal salt solution I, a high-concentration ammonia water complexing agent II and a high-concentration alkaline solution precipitant III into the reaction kettle at the same time, and carrying out coprecipitation crystallization reaction under stirring, wherein the constant feed speed, the constant system temperature and the constant reaction pH value are maintained in the process; the set temperature is 45-60 ℃; the value range of A is 11.0-11.8.
In the feeding process of the coprecipitation reaction, the flow rate of the high nickel metal salt solution I is B; the flow rate of the ammonia complexing agent II is controlled to be in NH according to the molar content of Ni in the material 3 : TM = between 1.1-1.5; the flow rate of the alkali liquor is used for regulating the pH value of a reaction system to be always constant at A, wherein TM is the sum of the amounts of Ni, co and Mn substances; the Ni molar content in the material is as follows: ni is more than or equal to 60% and less than 100%.
(3) Washing, filtering and drying a precursor;
releasing feed liquid after the reaction is finished, washing the precipitate by adopting alkaline water with the pH value of A1 for 3-4 times, thereby obtaining NH in the precipitate product 3 、SO 4 2- Wash away due to Na in alkaline water + The content of Na in the reaction liquid is far lower than that of Na in the reaction liquid + Concentration, most of Na in precipitate + Is also washed off in the alkaline washing process, and then washed once again with pure water, and the rest of Na which is very soluble + Washing off all, and finally placing the filtered precursor precipitation filter cake into a vacuum drying oven and drying at 100-120 ℃ for 12-20h to obtain dried high-nickel ternary precursor powder. A1=a+c; the value of C is 0-0.5.
As a preferable scheme, the preparation method of the alkaline water-washed high-nickel ternary precursor comprises the steps of; the soluble metal salt of nickel, cobalt and manganese is selected from one or more of metal sulfate, chloride, nitrate or acetate of nickel, cobalt and manganese; the alkali liquor is one or more of LiOH, naOH, KOH soluble alkali.
As a preferable scheme, the preparation method of the alkaline water-washed high-nickel ternary precursor comprises the steps of; the flow rate of the high nickel metal salt solution I is 0.7-20.0mL/min.
As a preferable scheme, the preparation method of the alkaline water-washed high-nickel ternary precursor comprises the steps of; the temperature of the feed liquid of the reaction kettle is constant within 45-60 ℃, the pH of the feed liquid of the reaction is controlled within 11.0-11.8, the stirring speed is controlled within 400-1000rpm, the feeding time is controlled within 10-30h, after the feeding of the coprecipitation reaction is finished, the heating and low-intensity stirring (200-400 rpm) are continuously maintained for 10-12h, the precipitation reaction is fully carried out, and finally the discharging, the washing, the filtering and the drying are carried out.
As a preferable scheme, the preparation method of the alkaline water-washed high-nickel ternary precursor comprises the steps of; releasing feed liquid after the reaction is finished, washing the precipitate by adopting NaOH alkaline water with the pH value of A1 for 3-4 times, wherein A1=A+C; the value of C is 0 to 0.5, more preferably 0 to 0.2.
The invention relates to a preparation method of a high-nickel ternary precursor washed by alkaline water; the particle size distribution of the obtained product is 5-15 μm.
The invention relates to a preparation method of a high-nickel ternary precursor washed by alkaline water; the flow rate of the ammonia complexing agent II is controlled to be in NH according to the molar content of Ni in the material 3 : the specific operations between tm=1.1-1.5 are: NH when Ni mole content in the material is 60% 3 The molar ratio to TM is close to or equal to 1.1, NH when the Ni content in the material is 90% 3 The molar ratio to TM is close to or equal to 1.5.
After optimization, the preparation method of the alkaline water-washed high-nickel ternary precursor is provided; chemical formula of precursorIs Ni 0.9 Co 0.05 Mn 0.05 (OH) 2 When the product D is obtained 10 6.8-7.5 μm, D 50 Is 9.5-10 μm, D 90 Is 12-13 μm, and has tap density of 2.0-2.10g.cm 3 。
After optimization, the preparation method of the alkaline water-washed high-nickel ternary precursor is provided; the chemical formula of the precursor is Ni 0.6 Co 0.2 Mn 0.2 (OH) 2 When the product D is obtained 10 Is 6-7 μm, D 50 Is 9-10 μm, D 90 Is 12-13 μm, and the tap density is 1.9-1.95 g.cm 3 。
The product obtained by the invention has excellent electrical properties, especially the cycle performance is far better than that of the similar products.
The invention has the advantages and beneficial effects that:
(1) Under the condition that the concentration of the metal salt solution is unchanged, high-concentration ammonia water is used as a complexing agent, high-concentration alkali liquor is used as a precipitator, the proportion of transition metal in a reaction system can be obviously increased by reducing the feeding speed of the ammonia water and the alkali liquor, so that the solid content and the production efficiency of the slurry are improved, and meanwhile, the collision friction among precursor particles is more frequent under the high solid content, so that the regulation and control of the spherical morphology of the precursor are facilitated;
(2) After the precursor feed liquid is discharged, the precipitate is washed for 3-4 times by adopting a proper amount of alkaline water and then washed once by pure water, so that not only can the morphology damage and the size shrinkage of precursor particles caused by the dissolution can be avoided, but also a good impurity ion washing effect can be realized, and the preparation process of the precursor is more controllable.
Drawings
FIG. 1 (a) shows Ni synthesized in example 1, (b) comparative example 1, (c) comparative example 2, and (d) comparative example 3 0.9 Co 0.05 Mn 0.05 (OH) 2 Precursor SEM pictures;
FIG. 2 shows the LiNi synthesized in example 1 0.9 Co 0.05 Mn 0.05 O 2 Discharge capacity decay curves of the material in the 1C and 2.8-4.3V intervals;
FIG. 3 is a diagram showing LiNi synthesized in comparative example 1 0.9 Co 0.05 Mn 0.05 O 2 Discharge capacity decay curves of the material in the 1C and 2.8-4.3V intervals;
FIG. 4 is a diagram showing LiNi synthesized in comparative example 2 0.9 Co 0.05 Mn 0.05 O 2 Discharge capacity decay curves of the material in the 1C and 2.8-4.3V intervals;
FIG. 5 shows the LiNi synthesized in comparative example 3 0.9 Co 0.05 Mn 0.05 O 2 Discharge capacity decay curves of the material in the 1C and 2.8-4.3V intervals;
FIG. 6 (a) shows Ni synthesized in example 2, (b) comparative example 4, (c) comparative example 5, and (d) comparative example 6 0.6 Co 0.2 Mn 0.2 (OH) 2 Precursor SEM pictures;
FIG. 7 shows the LiNi synthesized in example 2 0.6 Co 0.2 Mn 0.2 O 2 Discharge capacity decay curves of the material in the 1C and 2.8-4.3V intervals;
FIG. 8 shows the LiNi synthesized in comparative example 4 0.6 Co 0.2 Mn 0.2 O 2 Discharge capacity decay curves of the material in the 1C and 2.8-4.3V intervals;
FIG. 9 is a diagram of LiNi synthesized in comparative example 5 0.6 Co 0.2 Mn 0.2 O 2 Discharge capacity decay curves of the material in the 1C and 2.8-4.3V intervals;
FIG. 10 shows the LiNi synthesized in comparative example 6 0.6 Co 0.2 Mn 0.2 O 2 Discharge capacity decay curves of the material in the 1C and 2.8-4.3V intervals;
FIG. 11 is a drawing of Ni synthesized in comparative example 7 0.6 Co 0.2 Mn 0.2 (OH) 2 Precursor SEM pictures;
Detailed Description
The coprecipitation method preparation and alkaline water washing process of a high nickel ternary precursor according to the present invention are further described below with reference to examples, without limiting the present invention.
Example 1: preparation of high nickel Ni by high concentration ammonia-alkali 0.9 Co 0.05 Mn 0.05 (OH) 2 Washing the precursor with alkali-containing water
(1) Preparation of raw material liquids
1) According to the stoichiometric ratio of Ni: co: mn=9: 0.5:0.5 accurate weighing of soluble NiSO 4 ·6H 2 O、CoSO 4 ·7H 2 O and MnSO 4 ·H 2 Placing O salt in a beaker, adding a certain amount of hot pure water (40-50 ℃) to stir and ultrasonically dissolve, transferring to a volumetric flask after cooling to normal temperature, and fixing the volume to obtain a high nickel metal salt solution I, wherein the total concentration of metal ions of Ni, co and Mn is 2.0mol/L, and the volume is 1200mL;
2) Accurately measuring a certain volume of concentrated ammonia water in a volumetric flask by using a pipette, adding pure water to a certain volume to obtain 5.6mol/L ammonia water complexing agent II, wherein the volume of the solution is more than 600mL;
3) Rapidly weighing a certain amount of flaky sodium hydroxide in a beaker, adding cold pure water, stirring in a cold water bath for dissolution, and rapidly transferring to a volumetric flask for constant volume to obtain an alkali solution precipitant III, wherein the concentration of the alkali solution precipitant III is 8.0mol/L, and the volume of the solution is more than 800mL;
4) The preparation of the ammonia water bottom solution is the same as 2), the volume of the bottom solution is about 37.5 percent of the total volume of the reaction feed liquid after the feeding is finished, the concentration of the ammonia in the bottom solution is 1.4mol/L, and the volume is 1500mL;
(2) Co-precipitation reaction for preparing Ni 0.9 Co 0.05 Mn 0.05 (OH) 2 Precursor body
1) Before the experiment starts, the pH meter is calibrated at two points, pure water required by base solution is poured into a reaction kettle (5L) before reaction, the temperature in the circulating water heating kettle is pumped into an interlayer of the reaction kettle through a water bath, three feed pumps are used for pumping three feed pumps to the tail end of a feed inlet and stopping, nitrogen is continuously introduced into the kettle to exhaust air (the nitrogen is introduced below the liquid level, the flow of the nitrogen is proper, ammonia and heat in a reaction system are taken away too quickly, and Mn is easily caused too slowly) 2+ After the temperature in the kettle is increased to the reaction temperature, adding the concentrated ammonia water required by the bottom solution into the kettle through a feed port, starting stirring, wherein the pH value of the bottom solution is lower than the set value of the coprecipitation reaction, starting an alkaline pump, and regulating the pH value of the bottom solution to be the same as the reaction pH value by using alkaline solution;
2) Three feed pumps are provided, wherein the pump 1 is used for pumping the metal salt solution, and the flow thereofThe amount is controlled at 0.9mL/min, and the feeding time is about 22-24 h; the pumps 2 and 3 are respectively used for pumping ammonia water and alkali liquor, the flow rate is set according to the feeding speed of the metal salt of the pump 1 and the conversion of the reaction pH, wherein the feeding mole ratio of the metal salt and the ammonia water is always maintained at NH 3 : TM (tm=ni+co+mn) =1.4 (corresponding to an ammonia feed rate of 0.45 mL/min), the pH during the reaction is maintained at a constant value all the time by the feedback regulation mechanism of the lye pump; after the preparation process is finished, three feed pumps are started and timing is started, in the reaction process, the temperature in the kettle is controlled to be 50 ℃, the pH value of the feed liquid is kept constant at 11.6, and the stirring speed is 600rpm;
after the addition, the stirring intensity is slowed down to 300rpm, heating and stirring are continuously maintained for 10 hours, the precursor feed liquid is discharged and collected after the reaction is finished, the precursor feed liquid is kept stand for precipitation, the supernatant liquid is poured off, then the precipitation is washed for 4 times by alkaline water with pH of 11.6, and then is washed for 1 time by pure water for filtration, and then the precursor filter cake is transferred to a vacuum drying oven for drying at 110 ℃ for 12 hours to obtain Ni 0.9 Co 0.05 Mn 0.05 (OH) 2 The precursor has the morphology shown in figure 1 (a) and the particle size D 10 、D 50 、D 90 7.01, 9.73 and 12.82 μm respectively, and the tap density is 2.05 g.cm 3 The main impurity element content is shown in table 1 and meets the material preparation requirement; further mixing the precursor and LiOH H 2 O powder is fully and evenly mixed, presintered for 5 hours at 500 ℃ and sintered for 12 hours at 700 ℃ under the oxygen-enriched condition, and then LiNi is obtained 0.9 Co 0.05 Mn 0.05 O 2 The electrochemical performance test of the high nickel positive electrode material shows that the initial discharge capacity of the material in a voltage interval of 2.8-4.3V at 1C multiplying power is 184.2mAh/g, the capacity after 100 circles is 175.6mAh/g, and the capacity retention rate is 95.3% (the discharge capacity increase or fluctuation is caused by material activation at the beginning, and the same applies below).
Table 1 shows the Ni obtained in example 1 0.9 Co 0.05 Mn 0.05 (OH) 2 The main impurity element content of the precursor;
comparative example 1: preparation of high nickel Ni by high concentration ammonia-alkali 0.9 Co 0.05 Mn 0.05 (OH) 2 Washing the precursor with pure water
The same procedure as in the preparation of the raw material liquid and the coprecipitation reaction of example 1 was followed by washing the precursor with pure water for 5 times to obtain Ni 0.9 Co 0.05 Mn 0.05 (OH) 2 The precursor shape is shown in FIG. 1 (b), particle size D 10 、D 50 、D 90 6.39, 9.26 and 12.43 μm respectively, and the tap density value is 1.98 g.cm 3 Less than the example 1 precursor; the impurity element content thereof was in the same level range as the precursor obtained in example 1; the precursor was lithiated and sintered to LiNi in the same manner as in example 1 0.9 Co 0.05 Mn 0.05 O 2 The positive electrode material had a first discharge capacity of 184.5mAh/g at a 1C rate in the range of 2.8 to 4.3V, a capacity of 171.7mAh/g after 100 cycles, and a capacity retention of 93.1% (FIG. 3), which was inferior to that of example 1.
Comparative example 2: preparation of high nickel Ni by conventional concentration ammonia-alkali 0.9 Co 0.05 Mn 0.05 (OH) 2 Washing the precursor with alkali-containing water
(1) Preparation of raw material liquids
1) The concentration of the high nickel metal salt solution was 2.0mol/L as in example 1, but the salt solution volume was 800mL;
2) The concentration of the ammonia water complexing agent II is 2.8mol/L, and the volume is more than 800mL;
3) The concentration of the NaOH alkali solution precipitant III is 4.0mol/L, and the volume is more than 1000mL;
4) The concentration of the ammonia water bottom solution is 0.93mol/L, and the volume is 1500mL;
(2) Co-precipitation reaction for preparing Ni 0.9 Co 0.05 Mn 0.05 (OH) 2 Precursor body
The feeding rate of the high nickel metal salt solution was still 0.9mL/min, the feeding time was about 15 hours, and since the feeding ammonia concentration was reduced to half in example 1, the feeding rate of aqueous ammonia in this comparative example was set to be twice that in example 1, namely 0.9mL/min to ensure feeding NH 3 : the TM ratio was the same as in example 1, the alkali flow rate ensured that the pH of the feed solution was 11.6 and the reaction and subsequent washing were the same as in example 1.
The Ni obtained 0.9 Co 0.05 Mn 0.05 (OH) 2 The precursor shape is shown in FIG. 1 (c), particle size D 10 、D 50 、D 90 6.10, 9.02 and 12.27 μm respectively, and the tap density value is 1.97 g.cm 3 Less than the example 1 precursor; the impurity element content thereof was in the same level range as the precursor obtained in example 1; the precursor was lithiated and sintered to LiNi in the same manner as in example 1 0.9 Co 0.05 Mn 0.05 O 2 The positive electrode material has a first discharge capacity of 185.3mAh/g in a 1C rate and 2.8-4.3V interval, a capacity of 170.7mAh/g after 100 cycles, and a capacity retention rate of 92.1% (FIG. 4), and the material has still lower cycling stability than that of example 1.
Comparative example 3: preparation of high nickel Ni by conventional concentration ammonia-alkali 0.9 Co 0.05 Mn 0.05 (OH) 2 Washing the precursor with pure water
The same procedure as in the preparation of the raw material liquid and the coprecipitation reaction of comparative example 2 was followed by washing the precursor with pure water for 5 times to obtain Ni 0.9 Co 0.05 Mn 0.05 (OH) 2 The precursor shape is shown in FIG. 1 (D), particle size D 10 、D 50 、D 90 Respectively 5.84, 8.85 and 12.13 mu m, and the tap density value is 1.94g cm 3 Less than the example 1 precursor; the impurity element content thereof was in the same level range as the precursor obtained in example 1; the precursor was lithiated and sintered to LiNi in the same manner as in example 1 0.9 Co 0.05 Mn 0.05 O 2 The positive electrode material had a first discharge capacity of 184.7mAh/g at a 1C rate in the range of 2.8-4.3V, a capacity of 164.1mAh/g after 100 cycles, and a capacity retention of 88.8% (FIG. 5), and the cycling stability of the material was still inferior to that of example 1.
Compared with comparative examples 1-3, the embodiment 1 proves that the solid content of the reaction slurry can be increased by adopting high-concentration ammonia water and alkali liquor for coprecipitation synthesis reaction, the improvement of production efficiency is promoted, the particle morphology of a product is improved, the tap density of a material is improved, the precursor alkali water washing protects the morphology of the material from being damaged by washing with pure water, the size shrinkage of the particles caused by washing and dissolving with pure water is reduced to a great extent, and the electrochemical circulation stability is improved because the morphology and tap density of the product are improved in the preparation process of the high-concentration ammonia water-alkali liquor and under the washing condition of alkali containing water.
Example 2: preparation of high nickel Ni by high concentration ammonia-alkali 0.6 Co 0.2 Mn 0.2 (OH) 2 Washing the precursor with alkali-containing water
(1) Preparation of raw material liquids
1) According to the stoichiometric ratio Ni: co: mn=6: 2:2 preparing a high nickel metal salt solution I, wherein the total concentration of metal ions of Ni, co and Mn is 2.0mol/L, and the volume is 1200mL;
2) The concentration of the ammonia water complexing agent II is 4.4mol/L, and the volume is more than 600mL;
3) The concentration of the alkali solution precipitant III is 8.0mol/L, and the volume is more than 800mL;
4) The concentration of the ammonia water bottom solution IV is 1.1mol/L, and the volume is 1500mL;
(2) Co-precipitation reaction for preparing Ni 0.6 Co 0.2 Mn 0.2 (OH) 2 Precursor body
Substantially the same as in example 1, pump 1 was used to pump the metal salt solution I at a flow rate of 0.9mL/min for a feed time of about 22 to 24 hours; the pumps 2 and 3 are respectively used for pumping ammonia water and alkali liquor, the flow rate is set according to the feeding speed of the metal salt of the pump 1 and the conversion of the reaction pH, wherein the feeding mole ratio of the metal salt and the ammonia water is always maintained at NH 3 : TM (tm=ni+co+mn) =1.1 (corresponding to an ammonia feed rate of 0.45 mL/min), the pH is maintained at a constant value all the time during the reaction by the feedback adjustment mechanism of the lye pump; in the reaction process, the temperature in the kettle is controlled to be 55 ℃, the reaction pH is constant at 11.0, and the stirring speed is 400rpm;
after the addition is finished, the stirring intensity is slowed down to 200rpm, and heating and stirring are continuously maintained for 10 hours; washing precursor precipitate with alkaline water with pH of 11.0 for 4 times after reaction, and washing with pure waterOnce, transferring the precursor filter cake to a vacuum drying oven for drying at 110 ℃ for 12 hours after filtering to obtain Ni 0.6 Co 0.2 Mn 0.2 (OH) 2 The precursor has a morphology as shown in FIG. 6 (a) and a particle size D 10 、D 50 、D 90 6.83, 9.32 and 12.62 mu m, respectively, and the tap density is 1.92 g.cm 3 The main impurity element content is shown in table 2 and meets the material preparation requirement; further mixing the precursor and LiOH H 2 O powder is fully and evenly mixed, presintering is carried out for 5 hours at 500 ℃ and sintering is carried out for 12 hours at 800 ℃ under the oxygen-enriched condition, and then LiNi is obtained 0.6 Co 0.2 Mn 0.2 O 2 As shown in FIG. 7, the initial discharge capacity of the high-nickel positive electrode material in a voltage interval of 1C multiplying power and 2.8-4.3V is 149.7mAh/g, the capacity after 100 circles of circulation is 148.3mAh/g, and the capacity retention rate is 99.1%.
Table 2 shows the Ni obtained in example 2 0.6 Co 0.2 Mn 0.2 (OH) 2 The main impurity element content of the precursor;
comparative example 4: preparation of high nickel Ni by high concentration ammonia-alkali 0.6 Co 0.2 Mn 0.2 (OH) 2 Washing the precursor with pure water
The same procedure as in the preparation of the raw material liquid and the coprecipitation reaction of example 2 was followed by washing the precursor with pure water for 5 times to obtain Ni 0.6 Co 0.2 Mn 0.2 (OH) 2 The precursor body is as shown in FIG. 6 (b), and the impurity element content is in the same level range as that of the precursor obtained in example 2, and the particle size D 10 、D 50 、D 90 6.55, 9.04 and 12.46 mu m, respectively, and the tap density value is 1.89g cm 3 Less than the example 2 precursor; the precursor was lithiated and sintered to LiNi in the same manner as in example 2 0.6 Co 0.2 Mn 0.2 O 2 The first discharge capacity of the positive electrode material in the range of 2.8-4.3V at 1C multiplying power is 148.4Ah/g, and the capacity after 100 cycles is 14The capacity retention was 94.9% (FIG. 8) at 0.8mAh/g, which was less stable to cycling than example 2.
Comparative example 5: preparation of high nickel Ni by conventional concentration ammonia-alkali 0.6 Co 0.2 Mn 0.2 (OH) 2 Washing the precursor with alkali-containing water
(1) Preparation of raw material liquids
1) The concentration of the high nickel metal salt solution was 2.0mol/L as in example 2, but the salt solution volume was 800mL;
2) The concentration of the ammonia water complexing agent II is 2.8mol/L, and the volume is more than 800mL;
3) The concentration of the NaOH alkali solution precipitant III is 4.0mol/L, and the volume is more than 1000mL;
4) The concentration of the ammonia water bottom solution is 0.93mol/L, and the volume is 1500mL;
(2) Co-precipitation reaction for preparing Ni 0.6 Co 0.2 Mn 0.2 (OH) 2 Precursor body
The feeding rate of the high nickel metal salt solution was still 0.9mL/min, the feeding time was about 15 hours, and since the feeding ammonia concentration was reduced to half in example 1, the feeding rate of ammonia water in this comparative example was set to be twice that in example 2, namely 0.9mL/min, to ensure feeding NH 3 : the TM ratio was the same as in example 1, the alkali flow rate ensured that the pH of the feed solution was 11.0 and the reaction and subsequent washing were the same as in example 2.
The Ni obtained 0.6 Co 0.2 Mn 0.2 (OH) 2 The precursor body is as shown in FIG. 6 (c), and the impurity element content is in the same level range as that of the precursor obtained in example 2, and the particle size D 10 、D 50 、D 90 5.99, 8.64 and 12.17 μm respectively, and the tap density value is 1.84 g.cm 3 Less than the example 2 precursor; the precursor was lithiated and sintered to LiNi in the same manner as in example 2 0.6 Co 0.2 Mn 0.2 O 2 The positive electrode material had a first discharge capacity of 150.4mAh/g at a 1C rate in the range of 2.8-4.3V, a capacity of 140.9mAh/g after 100 cycles, and a capacity retention of 93.7% (FIG. 9), and the material had still lower cycle stability than in example 2.
Comparative example 6: ammonia-base of conventional concentrationPreparation of high Nickel Ni 0.6 Co 0.2 Mn 0.2 (OH) 2 Washing the precursor with pure water
The same procedure as in the preparation of the raw material liquid and the coprecipitation reaction of comparative example 5 was followed by washing the precursor with pure water for 5 times to obtain Ni 0.6 Co 0.2 Mn 0.2 (OH) 2 The precursor body is as shown in FIG. 6 (D), and the impurity element content is in the same level range as that of the precursor obtained in example 2, and the particle size D 10 、D 50 、D 90 5.65, 8.39 and 11.93 μm respectively, and the tap density value is 1.82 g.cm 3 Less than the example 2 precursor; the precursor was lithiated and sintered to LiNi in the same manner as in example 2 0.6 Co 0.2 Mn 0.2 O 2 The positive electrode material had a first discharge capacity of 152mAh/g at a 1C rate in the range of 2.8-4.3V, a capacity of 137mAh/g after 100 cycles, and a capacity retention of 90.1% (FIG. 10), and the material had still lower cycle stability than example 2.
This example again demonstrates that the co-precipitation reaction with high concentration ammonia water and alkali solution is conducive to particle agglomeration, and the precursor washing process adopts alkali-containing water washing to minimize damage to the morphology of the material, and the synthetic material has the best cycle performance.
Comparative example 7: preparation of high nickel Ni by low concentration ammonia-alkali 0.6 Co 0.2 Mn 0.2 (OH) 2 Washing the precursor with pure water
In this example, low concentration ammonia complexing agent II (1.0 mol/L) and NaOH alkali solution precipitant III (2.0 mol/L) were used to participate in the coprecipitation reaction, the pH of the reaction was 11.0, the stirring strength was 300rpm, and the other operations were the same as those of comparative example 6, to obtain Ni 0.6 Co 0.2 Mn 0.2 (OH) 2 The morphology of the product is shown in fig. 11, and it can be seen that the precursor particles randomly agglomerate and grow under the conditions of low ammonia-alkali concentration and insufficient stirring strength, and cannot grow into spherical particles with higher tap density, so the sample in this embodiment is a failure sample.
Claims (3)
1. A preparation method of a high-nickel ternary precursor containing alkaline water washing; the method is characterized in that: comprises the following steps of;
(1) Preparing various reaction raw material liquid;
the preparation of each reaction raw material liquid comprises the following steps: preparing a high nickel metal salt solution I, preparing an ammonia water complexing agent II, preparing an alkali solution precipitant III, and preparing ammonia water with a certain concentration as a reaction base solution IV before reaction feeding;
the preparation of the high nickel metal salt solution I comprises the following steps: accurately weighing soluble metal salts of nickel, cobalt and manganese according to the element design proportion of Ni, co and Mn in the material, placing the material in a storage tank, and adding hot water at 40-50 ℃ for rapid dissolution to ensure that the total concentration of metals in Ni, co and Mn solutions is 1.5-2.5mol/L;
the preparation of the alkali liquor precipitant III comprises the following steps: the concentration range of the alkali liquor is 6.0-10.0mol/L;
the preparation of the ammonia water complexing agent II comprises the following steps: the concentration range of the ammonia water is as follows: 4.4 to 6.0mol/L
The preparation of the reaction base solution IV comprises the following steps: the concentration range of the ammonia water is 1.1-1.5mol/L, and the volume of the base solution accounts for 1/3-1/2 of the volume of the reaction kettle;
(2) Preparation of high nickel precursor Ni by nickel cobalt manganese coprecipitation reaction x Co y Mn 1-x-y (OH) 2；
Wherein x is more than or equal to 0.6 and less than 1, y is more than or equal to 0 and less than 0.4, and x+y is more than or equal to 1;
pouring pure water required in the reaction base solution IV into a reaction kettle before reaction in the step (2), pumping circulating water into an interlayer of the reaction kettle through a water bath kettle to heat the reaction kettle, continuously introducing nitrogen into the kettle to exhaust air, adding a certain amount of concentrated ammonia water required in the base solution into the kettle through a feed inlet after the temperature in the kettle is raised to a set temperature, firstly starting an alkaline pump to add NaOH alkaline solution to raise the pH value of the base solution to a reaction set value A, then pumping a high-nickel metal salt solution I, a high-concentration ammonia water complexing agent II and a high-concentration alkaline solution precipitant III into the reaction kettle at the same time, and carrying out coprecipitation crystallization reaction under stirring, wherein the constant feed speed, the constant system temperature and the constant reaction pH value are maintained in the process; the set temperature is 45-60 ℃;
in the feeding process of the coprecipitation reaction, the flow rate of the high nickel metal salt solution I is B; flow rate of aqueous ammonia complexing agent IIControlling the feeding mole ratio at NH according to the Ni mole content in the material 3 : TM = between 1.1-1.5; the flow rate of the alkali liquor is used for regulating the pH value of a reaction system to be always constant at A, wherein TM is the sum of the amounts of Ni, co and Mn substances; the Ni molar content in the material is as follows: ni is more than or equal to 60% and less than 100%;
the temperature of the feed liquid of the reaction kettle is constant within 45-60 ℃, the pH of the feed liquid of the reaction is controlled within 11.0-11.8, the stirring speed is controlled within 400-1000rpm, the feeding time is controlled within 10-30h, after the feeding of the coprecipitation reaction is finished, the heating and low-intensity stirring are continuously maintained for 10-12h, the precipitation reaction is fully carried out, and finally the discharging, washing, filtering and drying are carried out, wherein the rotating speed of the low-intensity stirring is 200-400rpm;
(3) Washing, filtering and drying a precursor;
releasing feed liquid after the reaction is finished, washing the precipitate by adopting alkaline water with the pH value of A1 for 3-4 times, wherein A1=A+C; the value of C is 0-0.2, so that NH in the precipitated product 3 、SO 4 2- Wash away due to Na in alkaline water + The content of Na in the reaction liquid is far lower than that of Na in the reaction liquid + Concentration, most of Na in precipitate + Is also washed off in the alkaline washing process, and then washed once again with pure water, and the rest of Na which is very soluble + Washing off all, and finally placing the filtered precursor precipitation filter cake in a vacuum drying oven and drying at 100-120 ℃ for 12-20 hours to obtain dried high-nickel ternary precursor powder;
the chemical formula of the precursor is Ni 0.9 Co 0.05 Mn 0.05 (OH) 2 When the product D is obtained 10 6.8-7.5 μm, D 50 Is 9.5-10 μm, D 90 Is 12-13 μm, and has tap density of 2.0-2.10g/cm 3 ；
The chemical formula of the precursor is Ni 0.6 Co 0.2 Mn 0.2 (OH) 2 When the product D is obtained 10 Is 6-7 μm, D 50 Is 9-10 μm, D 90 Is 12-13 μm, and has tap density of 1.9-1.95g/cm 3 。
2. The method for preparing the alkaline-washed high-nickel ternary precursor according to claim 1; the method is characterized in that: the soluble metal salt of nickel, cobalt and manganese is selected from one or more of metal sulfate, nitrate or acetate of nickel, cobalt and manganese; the alkali liquor is one or more of LiOH, naOH, KOH soluble alkali.
3. The method for preparing the alkaline-washed high-nickel ternary precursor according to claim 1; the method is characterized in that: the flow rate of the high nickel metal salt solution I is 0.7-20.0mL/min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111539872.1A CN114057239B (en) | 2021-12-16 | 2021-12-16 | Preparation method of alkaline-water-washed high-nickel ternary precursor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111539872.1A CN114057239B (en) | 2021-12-16 | 2021-12-16 | Preparation method of alkaline-water-washed high-nickel ternary precursor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114057239A CN114057239A (en) | 2022-02-18 |
| CN114057239B true CN114057239B (en) | 2023-05-30 |
Family
ID=80229603
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111539872.1A Active CN114057239B (en) | 2021-12-16 | 2021-12-16 | Preparation method of alkaline-water-washed high-nickel ternary precursor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114057239B (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114655998A (en) * | 2022-03-01 | 2022-06-24 | 西安理工大学 | Preparation method of high-nickel ternary positive electrode precursor |
| CN116062804A (en) * | 2022-12-30 | 2023-05-05 | 宁波容百材料科技有限公司 | Ternary high-nickel precursor batching method |
| CN116425210A (en) * | 2023-02-17 | 2023-07-14 | 中国长江三峡集团有限公司 | High-nickel precursor, positive electrode material and preparation method of positive electrode material |
| CN116425211A (en) * | 2023-02-21 | 2023-07-14 | 广东邦普循环科技有限公司 | Ternary precursor with high nickel and large particles and preparation method thereof |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES291558A1 (en) * | 1962-10-11 | 1963-12-01 | Elektrokemisk As | Procedure for the separation of fluor, aluminum and sodium compounds from oven residues for the production of aluminum by fusion electrolysis (Machine-translation by Google Translate, not legally binding) |
| US8524177B2 (en) * | 2011-09-09 | 2013-09-03 | Canadus Chemical LLC | Process for purifying zinc oxide |
| CN105118981A (en) * | 2015-04-30 | 2015-12-02 | 宁夏东方钽业股份有限公司 | High-capacity nickel-cobalt-lithium manganate precursor and preparation method thereof |
| CN107565125B (en) * | 2017-08-25 | 2019-10-29 | 湖南杉杉能源科技股份有限公司 | A kind of high voltage precursor of nickel-cobalt-lithium-manganese-oxide and preparation method thereof and high voltage nickel-cobalt lithium manganate cathode material |
| CN112777647B (en) * | 2019-11-04 | 2023-04-07 | 巴斯夫杉杉电池材料有限公司 | High-nickel hydroxide with narrow particle size distribution and preparation method thereof |
| CN112357973A (en) * | 2020-09-30 | 2021-02-12 | 宜宾光原锂电材料有限公司 | Preparation method of positive electrode material precursor and prepared positive electrode material precursor |
-
2021
- 2021-12-16 CN CN202111539872.1A patent/CN114057239B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN114057239A (en) | 2022-02-18 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114057239B (en) | Preparation method of alkaline-water-washed high-nickel ternary precursor | |
| CN107324405B (en) | A kind of lithium nickel cobalt manganese oxide precursor and preparation method thereof and lithium ion battery by the precursor preparation | |
| CN108598441B (en) | Different-granularity narrow-distribution ternary precursor and preparation method thereof | |
| CN109686938B (en) | Magnesium ion doped gradient nickel cobalt lithium manganate positive electrode material and preparation method thereof | |
| CN109860581B (en) | Preparation method of spherical nickel cobalt manganese hydroxide precursor with narrow particle size distribution | |
| CN106564967B (en) | Lithium-rich manganese-based anode material presoma, positive electrode and preparation method thereof | |
| CN103311513B (en) | A kind of high-performance layed solid-solution lithium electricity positive electrode and preparation method thereof | |
| WO2019104473A1 (en) | Ternary precursor material and preparation method therefor | |
| CN106549150B (en) | A kind of preparation method of nickel manganese cobalt complex hydroxide and the reaction kettle for being used to prepare nickel manganese cobalt complex hydroxide | |
| CN110534719B (en) | Preparation method of aluminum-doped magnesium-nickel-manganese spherical cobaltosic oxide | |
| CN100334003C (en) | Nanometer alpha-nickel hydroxide and its prepn | |
| CN100452488C (en) | Preparation method of ternary compound potassium ion battery plus plate material | |
| CN106257718B (en) | A kind of BN cladding is without cobalt Ni-Mn solid solution nickel hydroxide base anode materials | |
| CN105355910B (en) | A kind of preparation method of lithium ion battery anode material spherical nickel cobalt lithium aluminate | |
| CN109626447A (en) | Nickelic anode material for lithium-ion batteries of a kind of concentration gradient magnesium doping and preparation method thereof | |
| CN103325992B (en) | Lithium ion battery positive electrode material precursor nickel-cobalt-manganese hydroxide powder and preparation method thereof | |
| CN102013481A (en) | Method for synthesizing spherical gradient lithium-rich anode material | |
| CN108428888B (en) | Spherical surface compact nickel-cobalt-aluminum ternary material, precursor thereof, preparation method and application thereof | |
| CN113851633B (en) | Niobium-doped high-nickel ternary cathode material coated with niobium phosphate and preparation method thereof | |
| WO2010139142A1 (en) | Positive electrode materials of secondary lithium battery and preparation methods thereof | |
| CN107565127B (en) | Preparation method of nitrogen-doped nickel-cobalt-manganese ternary material | |
| CN104649336B (en) | A kind of preparation method of spherical nickel-cobalt aluminium hydroxide presoma | |
| CN108706638B (en) | Preparation method of ternary precursor fine crystal nucleus | |
| CN111029561A (en) | Ternary lithium battery positive electrode material precursor and preparation method thereof, ternary lithium battery positive electrode material and preparation method and application thereof | |
| CN108264096B (en) | Preparation method of high-density small-particle nickel-cobalt-manganese hydroxide |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |