CN115819072A - Ternary cathode material and preparation method and application thereof - Google Patents
Ternary cathode material and preparation method and application thereof Download PDFInfo
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Abstract
The invention provides a ternary cathode material and a preparation method and application thereof, and relates to the technical field of battery materials. Mixing the raw materials, carrying out coprecipitation reaction, concentrating the obtained reactant to obtain precursor slurry I, then replacing water in the precursor slurry I by adopting an organic isolating agent, mixing the obtained precursor slurry II with a lithium source, coating the mixture on a high-temperature-resistant substrate, and sintering the mixture in sections to obtain a ternary cathode material; the precursor slurry II is directly mixed with a lithium source without washing and drying, so that the generation of waste water and the consumption of energy are reduced, and the organic isolating agent in the precursor slurry II can be volatilized at the initial stage of sintering, so that the sintering environment and the heating uniformity of a material layer cannot be greatly influenced; meanwhile, the mixed slurry is coated on the surface of the high-temperature resistant substrate to form a thin coating layer, so that the sintering contact area can be increased, the material sintering temperature can be reduced, the sintering time can be shortened, and the energy consumption can be further reduced.
Description
Technical Field
The invention belongs to the technical field of battery materials, and relates to a ternary cathode material, and a preparation method and application thereof.
Background
In recent years, the new energy field is rapidly developed, and batteries are widely applied to the fields of electric automobiles, portable electronic equipment, energy storage power stations and the like as an efficient energy conversion and storage device. With the rapid development of electric vehicles, people put higher demands on the endurance mileage of electric vehicles and the energy density of lithium ion batteries, and the anode materials of lithium ion batteries for vehicles are developing towards ternary batteries. Ternary cathode materials are gradually becoming a research hotspot due to the characteristics of high energy density, low cost and the like.
The preparation of the ternary positive electrode material is roughly classified into a solid-phase method and a solution method. The solid phase method is that the reaction raw materials are mixed in a solid phase form and participate in the reaction, and then high-temperature sintering is carried out. The method requires high sintering temperature and long reaction time, and the synthesized materials have larger difference in structure, particle size distribution and the like, so that the solid phase method is gradually replaced by the solution method. The solution method mainly comprises a sol-gel method, a spray pyrolysis method, a coprecipitation method and the like. Compared with the traditional solid phase method, the sol-gel method has the advantages that raw materials are uniformly dispersed, the synthesis and sintering temperatures are lower, the material with high chemical uniformity can be prepared, but the process is complicated, the productivity is low, and the industrialization difficulty is higher. The spray pyrolysis method is to spray raw materials into a reaction cavity through a fine nozzle, and the raw materials are atomized and react quickly at a certain temperature, but the equipment cost is high. The coprecipitation method generally includes mixing the raw materials in a solution state, adding a suitable precipitant to the solution to perform a coprecipitation reaction, thereby preparing a precursor, washing the obtained precursor with water, drying, and then mixing and sintering the precursor with a lithium source, thereby obtaining the ternary cathode material (for example, CN114843458 a). The coprecipitation method can be used for mixing materials at an atomic or molecular level, the obtained materials are uniform in appearance, and the method becomes a common method for preparing the ternary cathode material industrially due to simple process control and high capacity. However, there are some places to be improved, for example, the precursor water washing process generates a large amount of waste water, the energy consumption generated by the drying and sintering processes is high, and the sintered product usually needs to be crushed and sieved in multiple steps to obtain the ternary material, so that the whole process has multiple steps. Therefore, how to further reduce energy consumption, reduce wastewater generation, simplify the process flow and improve the production benefit is a technical problem which needs to be solved urgently in industrial preparation of the ternary cathode material.
In view of the above, the present invention is particularly proposed.
Disclosure of Invention
Aiming at the defects of the prior art, the invention aims to provide a ternary cathode material and a preparation method and application thereof; the preparation method is based on the original coprecipitation method, and comprises the steps of replacing moisture in precursor slurry I by using an organic isolating agent, directly mixing the obtained precursor slurry II with a lithium source by a wet method, coating a thin layer, and sintering in sections to obtain a ternary cathode material; the preparation process reduces the steps of washing and drying the precursor slurry and crushing the calcined product, the process is simple and controllable, the generation of waste water and the consumption of energy are reduced, the preparation cost is reduced, and the prepared ternary cathode material has good electrical property.
In order to realize the purpose, the following technical scheme is adopted:
the invention provides a preparation method of a ternary cathode material, which comprises the following steps:
(a) Mixing a nickel source, a cobalt source, a manganese source, a precipitator, a complexing agent and water in proportion to react, and concentrating after the reaction is finished to obtain precursor slurry I;
(b) Adding an organic separant into the precursor slurry I, and heating the precursor slurry I to replace the moisture in the precursor slurry I with the organic separant to obtain a precursor slurry II; wherein the boiling point of the organic isolating agent is 50-100 ℃ higher than that of water;
(c) And coating the mixed slurry formed by the lithium source and the precursor slurry II on a high-temperature-resistant substrate, then sintering the substrate in a segmented manner in an oxygen or air atmosphere, and separating the sintered material from the high-temperature-resistant substrate to obtain the ternary cathode material.
Further, on the basis of the above technical solution of the present invention, in the step (a), the precipitating agent includes at least one of sodium hydroxide, sodium carbonate, potassium carbonate or sodium bicarbonate;
and/or the complexing agent comprises at least one of ammonia monohydrate, monoethanolamine or sodium aminotriacetate;
and/or the solid content of the precursor slurry I is 75-85wt%.
Further, on the basis of the above technical solution of the present invention, in the step (b), the organic isolating agent includes at least one of ethylene glycol, anisole, or phenetole;
and/or the mass ratio of the organic separant to the water in the precursor slurry I is (1.2-2.0): 1.
further, on the basis of the technical scheme of the invention, in the step (b), the heating temperature is 100-130 ℃, and the heating time is 4-8h;
and/or the solid content of the precursor slurry II is 70-90wt%.
Further, on the basis of the technical scheme of the invention, in the step (c), the coating thickness of the mixed slurry on the surface of the high-temperature resistant substrate is 2-10cm;
and/or the high-temperature-resistant substrate is a high-temperature conveyor belt with nickel plated on the surface.
Further, on the basis of the above technical scheme of the present invention, in the step (c), the step of sintering in stages includes sequentially performing first-stage sintering, second-stage sintering, third-stage sintering, fourth-stage sintering, and fifth-stage sintering.
Further, on the basis of the technical scheme of the invention, the temperature of the first-stage sintering is 80-120 ℃, and the time is 0.5-1h;
and/or the temperature of the second-stage sintering is 150-300 ℃, and the time is 1-2h;
and/or the temperature of the three-stage sintering is 400-600 ℃, and the time is 1-2h;
and/or the temperature of the four-stage sintering is 650-850 ℃, and the time is 2-4h;
and/or the temperature of the five-stage sintering is 400-600 ℃, and the time is 0.2-0.5h.
Further, on the basis of the technical scheme of the invention, in the step (c), after the material obtained by sintering is separated from the high-temperature resistant substrate, acid washing is carried out, and then drying is carried out, so as to obtain the ternary cathode material;
the acid used for acid washing comprises at least one of hypophosphorous acid, glacial acetic acid or boric acid.
The invention also provides a ternary cathode material prepared by the preparation method of the ternary cathode material.
The invention also provides application of the ternary cathode material in the field of lithium ion batteries.
Compared with the prior art, the technical scheme of the invention at least has the following technical effects:
(1) The invention provides a preparation method of a ternary cathode material, which comprises the steps of mixing raw materials in proportion, carrying out coprecipitation reaction, concentrating a reactant obtained by the reaction to obtain a precursor slurry I, adding an organic isolating agent into the precursor slurry I to replace moisture in the precursor slurry I, coating a high-temperature-resistant substrate with mixed slurry obtained by mixing the obtained precursor slurry II and a lithium source, and carrying out sectional sintering to obtain the ternary cathode material; the organic isolating agent in the precursor slurry II can be volatilized at the initial stage of sintering, so that the sintering environment and the heating uniformity of a material layer cannot be greatly influenced; meanwhile, the mixed slurry is coated on the surface of the high-temperature resistant substrate to form a thin coating layer, so that the sintering contact area can be increased, the material sintering temperature can be reduced, the sintering time can be shortened, and the energy consumption can be further reduced. In addition, because the coating layer is thin, materials obtained by subsequent sintering can be directly subjected to ultrasonic screening treatment without multi-step crushing, and the process steps are greatly simplified.
(2) The invention also provides a ternary cathode material which is prepared by adopting the preparation method of the ternary cathode material. The ternary cathode material prepared by the preparation method has good electrochemical performance, and provides a foundation for the improvement of the performance of the subsequent lithium ion battery.
(3) The invention also provides application of the ternary cathode material in the field of lithium ion batteries. In view of the advantages of the ternary cathode material, the performance of the lithium ion battery is effectively improved, meanwhile, the preparation cost of the lithium ion battery can be reduced, the improvement of the production benefit is facilitated, and the ternary cathode material has a good application prospect in the field of lithium ion batteries.
Drawings
Fig. 1 to 10 are SEM images of ternary cathode materials provided in examples 1 to 10 of the present invention, respectively, wherein the scale of each figure is 15 μm;
fig. 11 to 15 are SEM images of the ternary cathode materials provided in comparative examples 1 to 5 of the present invention, respectively, wherein the scale is 15 μm in each of the figures.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. It should be understood by those skilled in the art that the examples are only for the understanding of the present invention and should not be construed as the specific limitations of the present invention. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention. The process parameters for the following examples, without specifying the particular conditions, are generally in accordance with conventional conditions.
The endpoints of the ranges and any values disclosed in the present application are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual values, and between the individual values may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.
According to a first aspect of the present invention, there is provided a method for preparing a ternary cathode material, comprising the steps of:
(a) Mixing a nickel source, a cobalt source, a manganese source, a precipitator, a complexing agent and water in proportion to react, and concentrating after the reaction is finished to obtain precursor slurry I;
(b) Adding an organic separant into the precursor slurry I, and heating the precursor slurry I to replace the moisture in the precursor slurry I with the organic separant to obtain a precursor slurry II; wherein the boiling point of the organic isolating agent is 50-100 ℃ higher than that of water;
(c) And coating the mixed slurry formed by the lithium source and the precursor slurry II on a high-temperature-resistant substrate, then sintering the substrate in a segmented manner in an oxygen or air atmosphere, and separating the sintered material from the high-temperature-resistant substrate to obtain the ternary cathode material.
Specifically, in the step (a), the nickel source, the cobalt source and the manganese source are mainly used for providing nickel element, cobalt element and manganese element. Specific kinds of the nickel source, the cobalt source, and the manganese source are not particularly limited, and soluble nickel salts, soluble cobalt salts, and soluble manganese salts, which are commonly used in the art, may be selected. The amounts of the nickel source, cobalt source, and manganese source may be determined according to the stoichiometric ratio of the ternary cathode material.
The precipitator is mainly used for carrying out coprecipitation reaction with a nickel source, a cobalt source and a manganese source so as to separate out nickel, cobalt and manganese in the form of precipitates. The kind of the precipitant can be selected from hydroxide or carbonate, etc.
The complexing agent is mainly used for complexing metal ions in a system so as to control the supersaturation degree of precipitates in a solution, reduce the nucleation and growth speeds and be beneficial to the slow growth of crystals.
The amounts of the precipitant and the complexing agent can be set by those skilled in the art according to the actual product requirements.
And (3) concentrating the reactant after the coprecipitation reaction is finished so as to enable the precursor slurry I to reach a certain solid content.
In the traditional method, the precursor slurry I is usually washed with water, dried, then mixed with lithium and sintered, but the precursor slurry I is not directly mixed with a lithium source. If the precursor slurry I is directly mixed with a lithium source, the moisture content in the precursor slurry I is high, a large amount of water vapor can be generated in the subsequent sintering process, the sintering environment is influenced, the material is dehydrated too much, the whole material layer is heated unevenly, and the sintering effect is influenced. The method is different from the traditional method in that the organic separant is added into the precursor slurry I in the step (b), and the water in the precursor slurry I is replaced by the organic separant, namely the solvent of the precursor slurry II is the organic separant. The organic isolating agent is selected from substances with boiling point 50-100 ℃ higher than that of water, lower cost and low toxicity. For example, the boiling point of the organic release agent may be 150 ℃, 155 ℃, 160 ℃, 165 ℃, 170 ℃, 175 ℃, 180 ℃, 185 ℃, 190 ℃, 195 ℃ or 200 ℃.
In the step (c), the precursor slurry II is directly mixed with a lithium source by a wet method without being washed and dried to form mixed slurry, and the mixed slurry is coated on a high-temperature-resistant substrate and then sintered. The boiling point of the organic isolating agent in the precursor slurry II is slightly higher, so that the organic isolating agent can be volatilized in the initial sintering stage (first-stage sintering and second-stage sintering), and the sintering environment and the heating uniformity of a material layer cannot be greatly influenced. Meanwhile, as the polarity of the organic isolating agent is less than that of water and the influence of hydrogen bonds is less, the stability (flowability, rheological property and leveling property) of the precursor slurry II and the mixed slurry can be ensured, the subsequent coating effect can be promoted, and the material layer is not easy to crack after sintering.
A thin coating layer is formed on the surface of the high-temperature resistant substrate in a coating mode, so that the sintering contact area can be increased, the material sintering temperature is reduced, the sintering time is shortened, and the energy consumption can be further reduced. Because the high-temperature resistant substrate is used as a carrier to be sintered together with the mixed slurry in a segmented manner, the temperature resistance degree of the high-temperature resistant substrate can meet the use requirement of subsequent sintering.
By adopting segmented sintering, the organic separant and the residual water in the precursor slurry II are conveniently removed in the early stage of sintering, the influence of the organic separant and the water is eliminated to the minimum, the subsequent sintering process is more sufficient, and the temperature difference is reduced at different temperature sections to avoid the condition of rapid temperature rise and rapid temperature reduction.
In addition, because the coating layer is thin, materials obtained by subsequent sintering can be directly subjected to ultrasonic screening treatment without multi-step crushing, and the process steps are greatly simplified.
The ternary cathode material prepared by the preparation method has good electrochemical performance, and provides a foundation for the improvement of the performance of the subsequent lithium ion battery.
The kind of each raw material in the step (a) is further limited.
As an alternative embodiment of the present invention, the nickel source comprises at least one of nickel sulfate, nickel chloride or nickel nitrate;
the cobalt source comprises at least one of cobalt sulfate, cobalt chloride or cobalt nitrate;
the manganese source comprises at least one of manganese sulfate, manganese chloride or manganese nitrate.
As an alternative embodiment of the present invention, in step (a), the precipitant comprises a hydroxide, carbonate or bicarbonate, preferably at least one of sodium hydroxide, sodium carbonate, potassium carbonate or sodium bicarbonate.
As an alternative embodiment of the present invention, the complexing agent comprises at least one of ammonia monohydrate, monoethanolamine, or sodium aminotriacetate.
The amount of each raw material can be set according to actual needs. For example, when the concentration of the ternary feed liquid formed by the nickel source, the cobalt source and the manganese source is 220-240g/L (such as 220g/L, 230g/L or 240 g/L), the concentration of the precipitating agent in the precipitating agent aqueous solution is 430-470g/L (such as 430g/L, 440g/L, 450g/L, 460g/L or 470 g/L), the concentration of the complexing agent in the complexing agent aqueous solution is 200-240g/L (such as 200g/L, 210g/L, 220g/L, 230g/L or 240 g/L), the flow ratio of the ternary feed liquid, the precipitating agent aqueous solution and the complexing agent aqueous solution is (5-10): (2.5-5): (1-2). A typical but non-limiting flow ratio is 5:2.5: 1.6: 2.5: 1.8: 2.5: 1.10: 2.5: 1.5: 3:1.5, 6:4: 1.8: 4:1 or 10:5:1, etc.
As an alternative embodiment of the present invention, in step (a), the precursor slurry I has a solids content of 75 to 85 wt.%. Typical but non-limiting solids content in precursor slurry i is 75%, 78%, 80%, 82%, 84%, or 85%.
Further optimizing the amount of raw materials and process conditions in step (b).
The amount of organic release agent is greater than the mass of water in the precursor slurry I. As an optional embodiment of the invention, in the step (b), the mass ratio of the organic release agent to the water in the precursor slurry I is (1.2-2.0): 1, typical but not limiting mass ratio 1.2: 1. 1.25: 1. 1.3: 1. 1.35: 1. 1.4: 1. 1.5: 1. 1.6: 1. 1.7: 1. 1.8: 1. 1.9:1 or 2.0:1. the excess organic release agent allows the water in the precursor slurry I to be adequately displaced.
As an alternative embodiment of the present invention, in the step (b), the heating temperature is 100-130 ℃ and the heating time is 4-8h. Typical but not limiting heating temperatures are 100 ℃, 110 ℃, 120 ℃ or 130 ℃, and typical but not limiting heating times are 4h, 5h, 6h, 7h or 8h.
At the heating temperature, the organic separant and the water are continuously evaporated, the moisture content of the slurry in the reaction kettle is sampled and detected, and the heating can be stopped when the moisture content is less than 0.5 wt%.
In order to facilitate later-stage coating, after heating is stopped, the solid content of the precursor slurry II can be controlled by adding a proper amount of organic separant. As an alternative embodiment of the present invention, in step (b), the solid content of the precursor slurry II is 70 to 90wt%. Typical but non-limiting solids contents are 70wt%, 75wt%, 80wt%, 85wt% or 90wt%. And if the solid content of the precursor slurry II reaches the coating requirement after the heating is stopped, the organic isolating agent does not need to be supplemented.
Step (c) is mainly a lithium mixing process. And mixing the lithium source and the precursor slurry II in proportion, wherein the mass ratio of the lithium source to the dry weight of the precursor is (1.05-1.15): 1 (e.g., 1.05.
The coating thickness of the mixed slurry on the surface of the high-temperature resistant substrate can be further optimized. In an alternative embodiment of the present invention, in the step (c), the mixed slurry is coated on the surface of the refractory substrate to a thickness of 2 to 10cm. Typical but non-limiting coating thicknesses are 2cm, 3cm, 4cm, 5cm, 6cm, 8cm or 10cm.
As an optional embodiment of the invention, the high-temperature resistant substrate is a high-temperature conveyor belt with nickel plated on the surface, and the nickel plating treatment on the surface of the high-temperature conveyor belt is selected, so that the adhesive force between the slurry coating and the high-temperature conveyor belt can be increased, and meanwhile, the continuous production is realized. The temperature resistance temperature of the high-temperature conveyor belt is at least higher than the highest sintering temperature of the subsequent sintering.
As an alternative embodiment of the present invention, in the step (c), the step of sintering in stages includes sequentially performing first-stage sintering, second-stage sintering, third-stage sintering, fourth-stage sintering and fifth-stage sintering.
The first-stage sintering is mainly used for removing residual moisture in the precursor slurry II, the temperature of the first-stage sintering is 80-120 ℃, and the time is 0.5-1h; typical but not limiting sintering temperatures are 80 ℃, 90 ℃, 100 ℃, 110 ℃ or 120 ℃, typical but not limiting sintering times are 0.5h, 0.75h or 1h;
the second-stage sintering is mainly to remove the organic isolating agent in the precursor slurry II, the temperature of the second-stage sintering is 150-300 ℃, and the time is 1-2 hours; typical but not limiting sintering temperatures are 150 ℃, 180 ℃, 200 ℃, 220 ℃, 240 ℃, 250 ℃, 280 ℃ or 300 ℃, typical but not limiting sintering times are 1h, 1.5h or 2h;
three-stage sintering mainly comprises increasing the material temperature and controlling the balanced heating rate. The temperature of the three-stage sintering is 400-600 ℃, and the time is 1-2h; typical but not limiting sintering temperatures are 400 ℃, 450 ℃, 480 ℃, 500 ℃, 520 ℃, 550 ℃, 580 ℃ or 600 ℃, typical but not limiting sintering times are 1h, 1.5h or 2h;
the four-stage sintering mainly carries out sintering reaction to form relatively complete single crystal particles. The temperature of the four-stage sintering is 650-850 ℃, and the time is 2-4h; typical but not limiting sintering temperatures are 650 ℃, 680 ℃, 700 ℃, 720 ℃, 750 ℃, 780 ℃, 800 ℃, 820 ℃ or 850 ℃, typical but not limiting sintering times are 2h, 3h or 4h;
the five-section sintering is mainly a cooling transition section, and the cooling rate is controlled. The temperature of the five-stage sintering is 400-600 ℃, and the time is 0.2-0.5h; typical but not limiting sintering temperatures are 650 ℃, 680 ℃, 400 ℃, 420 ℃, 450 ℃, 480 ℃, 500 ℃, 520 ℃, 550 ℃, 580 ℃ or 600 ℃, typical but not limiting sintering time is 0.2h or 0.5h.
In addition, when the high-temperature resistant substrate is a high-temperature conveyor belt with nickel plated on the surface, the material temperature change of the bottom layer (the side close to the conveyor belt) of the mixed slurry is slow, and the material temperature can also reach the temperature control requirement of each section by adopting sectional sintering.
As an optional embodiment of the present invention, in the step (c), after the material obtained after the sintering is separated from the high temperature resistant substrate, the material is subjected to acid washing and then dried to obtain the ternary cathode material.
As an alternative embodiment of the present invention, the acid used for acid washing includes at least one of hypophosphorous acid, glacial acetic acid, or boric acid; preferably, the concentration of the acid is 0.01 to 1mol/L.
By adopting the weak acid for slow washing, impurities such as Na (precipitator) and the like are fully separated out and reacted under a low-temperature environment, and meanwhile, the pH value of the surface of the particles is reduced, so that the subsequent treatment is facilitated.
According to the second aspect of the invention, the invention also provides a ternary cathode material which is prepared by adopting the preparation method of the ternary cathode material.
According to the third aspect of the invention, the application of the ternary cathode material or the preparation method of the ternary cathode material in the field of lithium ion batteries is also provided.
In view of the advantages of the ternary cathode material, the performance of the lithium ion battery is effectively improved, meanwhile, the preparation cost of the lithium ion battery can be reduced, the improvement of the production benefit is facilitated, and the ternary cathode material has a good application prospect in the field of lithium ion batteries.
The present invention will be described in further detail with reference to specific examples and comparative examples. It should be noted that nickel, cobalt, manganese, lithium, sodium hydroxide, and ammonia monohydrate were used as the nickel source, the cobalt source, the manganese source, the lithium source, the precipitant, and the complexing agent, respectively, in the following examples and comparative examples.
Example 1
The embodiment provides a preparation method of a ternary cathode material, which comprises the following steps:
(1) Mixing a nickel source, a cobalt source and a manganese source according to a molar ratio of 8:1:1 and water are prepared into ternary feed liquid, then the ternary feed liquid (the concentration is 230 g/L), a precipitator aqueous solution (the concentration is 450 g/L) and a complexing agent aqueous solution (the concentration is 220 g/L) are added into a reaction kettle according to the parallel flow of 5L/min, 2.1L/min and 0.3L/min, the temperature is 50 ℃, the stirring is carried out at 450rpm, the precipitation is carried out until the granularity is 4 +/-0.5 mu m, the feeding is stopped, the slurry is concentrated until the solid content is 85%, and the nitrogen is continuously introduced for protection in the reaction process, so that precursor slurry I is obtained;
(2) Adding excessive organic separant anisole into the reaction kettle, wherein the mass ratio of the anisole to the moisture in the precursor slurry I is 1.2:1, heating a reaction kettle to 100 ℃, stirring, detecting that the water content of slurry in the reaction kettle is 0.3wt% after 4 hours, stopping heating, and supplementing a proper amount of anisole until the solid content of the slurry is 75% so as to facilitate subsequent coating, thereby obtaining precursor slurry II;
(3) Continuously coating a mixed slurry formed by mixing a lithium source and a precursor slurry II according to a ratio (the mass ratio of the lithium source to the dry weight of the precursor is 1.10);
(4) 50L of salt-free water is added into a reaction kettle, protective gas is introduced, the temperature is 20 ℃, the stirring is carried out at 300rpm, and the prepared high-Na ternary cathode material is prepared according to the following materials: and (2) adding water =1.05 into the reaction kettle, stirring for 10min, then slowly adding 10L of glacial acetic acid with the concentration of 0.05mol/L within 20min, and drying after the acid washing is finished to obtain the ternary cathode material.
Example 2
The embodiment provides a preparation method of a ternary cathode material, except that the mass ratio of the organic isolating agent anisole in the step (2) to the moisture in the precursor slurry I is changed from 1.2:1 is replaced by 1.6:1, the rest of the steps and the process parameters are the same as in example 1.
Example 3
The embodiment provides a preparation method of a ternary cathode material, except that the mass ratio of anisole as an organic separant in the step (2) to water in the precursor slurry i is controlled from 1.2:1 is replaced by 2.0:1, the rest of the steps and the process parameters are the same as in example 1.
Example 4
The embodiment provides a preparation method of a ternary cathode material, except that in the step (3), the four-stage sintering temperature is replaced by 850 ℃ from 650 ℃, the five-stage sintering temperature is replaced by 600 ℃, and other steps and process parameters are the same as those in the embodiment 3.
Example 5
The embodiment provides a preparation method of a ternary cathode material, which is the same as that of the embodiment 4 except that the first-stage sintering temperature in the step (3) is changed from 80 ℃ to 120 ℃, the second-stage sintering temperature is changed from 150 ℃ to 300 ℃, and the third-stage sintering temperature is changed from 400 ℃ to 600 ℃.
Example 6
This example provides a method for preparing a ternary cathode material, which is the same as example 5 except that the fourth sintering time in step (3) is adjusted from 2h to 4h, and the remaining steps and process parameters are the same as those in example 5.
Example 7
This example provides a method for preparing a ternary cathode material, which comprises the same steps and process parameters as in example 5, except that the coating thickness of the mixed slurry in step (3) was adjusted from 2cm to 6 cm.
Example 8
This example provides a method for preparing a ternary cathode material, which comprises the same steps and process parameters as in example 5, except that the coating thickness of the mixed slurry in step (3) was adjusted from 2cm to 10cm.
Example 9
This example provides a method for preparing a ternary cathode material, except that the organic isolating agent in step (2) is replaced by ethylene glycol from anisole, and the amount is kept unchanged, and the other steps and process parameters are the same as those in example 1.
Example 10
This example provides a method for preparing a ternary cathode material, except that the organic isolating agent in step (2) is replaced by anisole, and the amount of the organic isolating agent is kept unchanged, and the other steps and process parameters are the same as those in example 1.
Comparative example 1
The comparative example provides a preparation method of a ternary cathode material, comprising the following steps:
(1) Mixing a nickel source, a cobalt source and a manganese source according to a molar ratio of 8:1:1 and water are prepared into ternary feed liquid, then the ternary feed liquid (the concentration is 230 g/L), a precipitator aqueous solution (the concentration is 450 g/L) and a complexing agent aqueous solution (the concentration is 220 g/L) are added into a reaction kettle according to the parallel flow of 5L/min, 2.1L/min and 0.3L/min, the temperature is 50 ℃, the stirring is carried out at 450rpm, the precipitation is carried out until the granularity is 4 +/-0.5 mu m, the feeding is stopped, the slurry is concentrated until the solid content is 85%, and the nitrogen is continuously introduced for protection in the reaction process, so that precursor slurry I is obtained;
(2) Washing and drying the precursor slurry I, removing impurities and moisture, and then mixing the precursor, lithium salt and an additive (nano-alumina) according to a mass ratio of 1:1.10: adding the mixture into a ball milling tank in a proportion of 0.03, uniformly mixing, and then loading into a sagger;
(3) The temperature of the roller kiln is set to 600 ℃, oxygen is introduced after preheating is completed, the oxygen content in the oven is detected to be more than 97% after 4 hours, the sagger is sent into the roller kiln to be sintered for 22 hours, and then the sagger is subjected to roller pair crushing, water washing and sieving (the mesh number of a screen is 300 meshes), and screen underflow is taken out, so that the ternary cathode material is obtained.
Comparative example 2
The comparative example provides a preparation method of a ternary cathode material, except that the sintering temperature in the step (3) is replaced by 700 ℃ from 600 ℃, and the rest steps and process parameters are the same as those of the comparative example 1.
Comparative example 3
The comparative example provides a preparation method of a ternary cathode material, except that the sintering temperature in the step (3) is replaced by 850 ℃ from 600 ℃, and the rest steps and process parameters are the same as those of the comparative example 1.
Comparative example 4
The comparative example provides a preparation method of a ternary cathode material, except that the sintering time in the step (3) is replaced by 10h from 22h, and the rest steps and process parameters are the same as those of the comparative example 1.
Comparative example 5
This comparative example provides a method for preparing a ternary positive electrode material, which is the same as in example 1, except that the precursor slurry i was not replaced with an organic separator (i.e., step (2) was not performed), but a mixed slurry formed by mixing the precursor slurry i with a lithium source was directly and continuously applied to a nickel-plated high-temperature belt.
In order to compare the technical effects of the above examples and comparative examples, the following experimental examples were specifically set.
Experimental example 1
The structures of the ternary cathode materials prepared in examples 1 to 10 and comparative examples 1 to 5 were examined by scanning electron microscopy. Fig. 1-15 show SEM images of ternary materials provided by various examples of the present invention and comparative examples. As can be seen from fig. 4 to 6, both of example 4 and example 5 had large single crystal grains due to the excessively high sintering temperature. Example 6 single crystal grains were large due to too high sintering temperature and too long sintering time, and there was no significant difference in the rest.
As shown in fig. 11, comparative example 1 has small single crystal grains due to too low sintering temperature. As can be seen from fig. 14, comparative example 4 has small single crystal grains due to too short sintering time, and the rest is not clearly distinguished.
Experimental example 2
The materials prepared in examples 1 to 10 and comparative examples 1 to 5 of the present invention were used as active materials, the binder was PVDF, the conductive agent was SP, and the active materials: adhesive: the mass ratio of the conductive agent is 96:2:2, dissolving the mixture in a CMC solvent to prepare slurry, uniformly coating the slurry on a metal aluminum foil, drying the metal aluminum foil in vacuum, and cutting the metal aluminum foil into a circular pole piece with the diameter of 14mm by using a punch as a working electrode; in a clean glove box filled with argon (O) 2 The content is less than 0.1ppm 2 O content less than 0.1 ppm), metal lithium sheet is taken as a counter electrode, celgard2400 porous propylene membrane is taken as a diaphragm, and electrolyte is 1mol/L lithium hexafluorophosphate (LiPF) 6 ) Solution, solvent Ethylene Carbonate (EC): ethyl carbonate (DMC) =1:1, preparing a button battery (with the model of CR 2032) according to a certain assembly process, and standing for 24 hours after the button battery is completed to fully infiltrate electrolyte and electrode materials; under the room temperature condition (25 ℃ +/-1) and under the test condition of the voltage of 2.8V-4.3V, the test current density is 170mAh/g, the test result is shown in table 1, and table 1 respectively shows the first-circle charge-discharge capacity and the first-effect under the 0.1C multiplying condition (0.1C is the nominal capacity under 0.1 times, namely the load mass of the working electrode and the current density are 0.1).
TABLE 1
As can be seen from table 1, the ternary cathode materials prepared by the preparation methods of the examples of the present invention have better capacity and cycle performance than those of the comparative examples 1 to 5.
The above description is only exemplary of the invention and should not be taken as limiting the invention, as any modification, equivalent replacement, or improvement made within the spirit and principle of the invention is intended to be covered by the appended claims.
Claims (10)
1. The preparation method of the ternary cathode material is characterized by comprising the following steps of:
(a) Mixing a nickel source, a cobalt source, a manganese source, a precipitator, a complexing agent and water in proportion to react, and concentrating after the reaction is finished to obtain precursor slurry I;
(b) Adding an organic separant into the precursor slurry I, and heating the precursor slurry I to replace moisture in the precursor slurry I with the organic separant to obtain a precursor slurry II; wherein the boiling point of the organic isolating agent is 50-100 ℃ higher than that of water;
(c) And coating the mixed slurry formed by the lithium source and the precursor slurry II on a high-temperature-resistant substrate, then sintering the substrate in a segmented manner in an oxygen or air atmosphere, and separating the sintered material from the high-temperature-resistant substrate to obtain the ternary cathode material.
2. The method of preparing a ternary cathode material according to claim 1, wherein in step (a), the precipitant comprises at least one of sodium hydroxide, sodium carbonate, potassium carbonate, or sodium bicarbonate;
and/or the complexing agent comprises at least one of ammonia monohydrate, monoethanolamine or sodium aminotriacetate;
and/or the solid content of the precursor slurry I is 75-85wt%.
3. The method for preparing a ternary cathode material according to claim 1, wherein in the step (b), the organic separator comprises at least one of ethylene glycol, anisole or phenetole;
and/or the mass ratio of the organic separant to the water in the precursor slurry I is (1.2-2.0): 1.
4. the method for preparing a ternary cathode material according to claim 1, wherein in the step (b), the heating temperature is 100-130 ℃ and the heating time is 4-8h;
and/or the solid content of the precursor slurry II is 70-90wt%.
5. The method for preparing a ternary cathode material according to any one of claims 1 to 4, wherein in the step (c), the mixed slurry is coated on the surface of the high temperature-resistant substrate to a thickness of 2 to 10cm;
and/or the high-temperature-resistant substrate is a high-temperature conveyor belt with nickel plated on the surface.
6. The method for preparing a ternary cathode material according to any one of claims 1 to 4, wherein in the step (c), the step sintering comprises sequentially performing first-stage sintering, second-stage sintering, third-stage sintering, fourth-stage sintering and fifth-stage sintering.
7. The preparation method of the ternary cathode material according to claim 6, wherein the temperature of the first-stage sintering is 80-120 ℃ and the time is 0.5-1h;
and/or the temperature of the second-stage sintering is 150-300 ℃, and the time is 1-2h;
and/or the temperature of the three-stage sintering is 400-600 ℃, and the time is 1-2h;
and/or the temperature of the four-stage sintering is 650-850 ℃, and the time is 2-4h;
and/or the temperature of the five-stage sintering is 400-600 ℃, and the time is 0.2-0.5h.
8. The method for preparing the ternary cathode material according to any one of claims 1 to 4, wherein in the step (c), the material obtained by sintering is separated from the high-temperature resistant substrate, and then is subjected to acid washing and drying to obtain the ternary cathode material;
the acid used for acid washing comprises at least one of hypophosphorous acid, glacial acetic acid or boric acid.
9. A ternary cathode material, characterized by being prepared by the method for preparing a ternary cathode material according to any one of claims 1 to 8.
10. The use of the ternary positive electrode material of claim 9 in the field of lithium ion batteries.
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Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030215606A1 (en) * | 2002-05-17 | 2003-11-20 | Clancy Donald J. | Dispersible dielectric particles and methods of forming the same |
| CN103107309A (en) * | 2013-01-31 | 2013-05-15 | 中国科学技术大学 | Lithium ion battery positive pole and preparation method thereof |
| CN103840135A (en) * | 2014-03-27 | 2014-06-04 | 合肥国轩高科动力能源股份公司 | Preparation method for lithium titanate material membrane electrode |
| CN107248568A (en) * | 2017-07-12 | 2017-10-13 | 湖南艾威尔新能源科技有限公司 | Positive electrode adds the processing method of graphene |
| CN109994728A (en) * | 2019-03-29 | 2019-07-09 | 宁波容百新能源科技股份有限公司 | The one nickelic positive electrode and preparation method thereof with uniform clad |
| CN113023789A (en) * | 2021-02-26 | 2021-06-25 | 南通金通储能动力新材料有限公司 | Olive-type carbonate ternary precursor with large specific surface area and preparation method thereof |
| CN113036095A (en) * | 2020-03-27 | 2021-06-25 | 湖南杉杉能源科技股份有限公司 | Preparation method of single-crystal-morphology lithium ion battery positive electrode material |
| CN113666429A (en) * | 2021-07-30 | 2021-11-19 | 蜂巢能源科技有限公司 | Doped ternary cathode material and preparation method and application thereof |
-
2022
- 2022-12-15 CN CN202211616947.6A patent/CN115819072B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030215606A1 (en) * | 2002-05-17 | 2003-11-20 | Clancy Donald J. | Dispersible dielectric particles and methods of forming the same |
| CN103107309A (en) * | 2013-01-31 | 2013-05-15 | 中国科学技术大学 | Lithium ion battery positive pole and preparation method thereof |
| CN103840135A (en) * | 2014-03-27 | 2014-06-04 | 合肥国轩高科动力能源股份公司 | Preparation method for lithium titanate material membrane electrode |
| CN107248568A (en) * | 2017-07-12 | 2017-10-13 | 湖南艾威尔新能源科技有限公司 | Positive electrode adds the processing method of graphene |
| CN109994728A (en) * | 2019-03-29 | 2019-07-09 | 宁波容百新能源科技股份有限公司 | The one nickelic positive electrode and preparation method thereof with uniform clad |
| CN113036095A (en) * | 2020-03-27 | 2021-06-25 | 湖南杉杉能源科技股份有限公司 | Preparation method of single-crystal-morphology lithium ion battery positive electrode material |
| CN113023789A (en) * | 2021-02-26 | 2021-06-25 | 南通金通储能动力新材料有限公司 | Olive-type carbonate ternary precursor with large specific surface area and preparation method thereof |
| CN113666429A (en) * | 2021-07-30 | 2021-11-19 | 蜂巢能源科技有限公司 | Doped ternary cathode material and preparation method and application thereof |
Non-Patent Citations (1)
| Title |
|---|
| 郑育英等: "超细二氧化锆干燥方式探讨", 无机盐工业, vol. 37, no. 09, pages 15 - 16 * |
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