CN114249355B - Layered cobaltosic oxide material and preparation method and application thereof - Google Patents
Layered cobaltosic oxide material and preparation method and application thereof Download PDFInfo
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Abstract
The application discloses a layered cobaltosic oxide material, a preparation method and application thereof. The layered cobaltosic oxide material comprises a plurality of loose layers and a plurality of compact layers, wherein the loose layers and the compact layers are overlapped from inside to outside, the loose layers are positioned at the center, the compact layers are positioned at the outermost layers, and the density of the loose layers is smaller than that of the compact layers. The layered cobaltosic oxide material provided by the application has regular morphology, is internally provided with a multi-layer loose and compact layered structure, has a stable and ordered structure and uniform morphology, is used for preparing lithium ion batteries, and can improve the cycle stability of battery materials.
Description
Technical Field
The application relates to the technical field of lithium ion battery anode materials, in particular to a layered cobaltosic oxide material and a preparation method and application thereof.
Background
With the rapid development of social economy, worldwide problems such as energy shortage, environmental protection, peak carbon, carbon neutralization and the like are receiving more and more attention, and the utilization of clean renewable energy sources becomes a future development trend.
The lithium cobaltate anode material is widely applied to the fields of 3C, electric vehicles, electric tools, energy storage, wearable electronic products and the like because of the high voltage, high power and stable cycle performance. The lithium cobaltate is prepared by taking lithium carbonate and cobaltosic oxide as raw materials and adopting a high-temperature solid phase method; the cobaltosic oxide is used as a precursor of the lithium cobalt oxide positive electrode material, and the granularity, the consistency, the surface morphology and the internal structure of the cobaltosic oxide have important influence on the performance of the lithium cobalt oxide positive electrode material. For example, the internal structure of the cobaltosic oxide can influence the development of primary particles of lithium cobaltate so as to influence the cycle performance of a lithium ion battery, so that the control of the internal structure of the cobaltosic oxide has important significance.
In the prior art, a co-precipitation method is generally adopted to combine with calcination to prepare the cobaltosic oxide material with the nano structure. However, the prepared nano-structure material is usually small in size and loose in structure, so that the density is low, the cycle stability of the battery material is not facilitated, and the energy density of the battery is reduced. Patent CN110078132A discloses a method for preparing doped cobaltosic oxide by intermittent coating, wherein the doping distribution of aluminum in the prepared cobaltosic oxide material is uniform and the structure is compact by controlling the gradient addition of cobalt salt in the coprecipitation process; the laser granularity D50 of the prepared large-granularity cobaltosic oxide is 17-19 mu m, and the laser granularity D50 of the small-granularity cobaltosic oxide is 3-5 mu m. However, as can be seen from a scanning electron microscope image, the prepared cobaltosic oxide material has irregular shape, a plurality of macropores on the surface, an uneven external structure and a tap density of only 2.0g/cm 3 About, this is unfavorable for improving the cycle performance of the lithium cobaltate cathode material.
Therefore, the cobaltosic oxide material which is regular in morphology, uniform in internal and external structure and adjustable is developed, and has important research significance and application value.
Disclosure of Invention
In order to solve the problems, the application provides a layered cobaltosic oxide material.
The application further aims at providing a preparation method of the layered cobaltosic oxide material.
Another object of the present application is to provide an application of the layered tricobalt tetraoxide material in the preparation of lithium ion batteries.
The application provides a layered cobaltosic oxide material which comprises a plurality of loose layers and a plurality of compact layers, wherein the loose layers and the compact layers are overlapped from inside to outside, the loose layers are positioned at the center, the compact layers are positioned at the outermost layers, and the density of the loose layers is smaller than that of the compact layers.
The application also provides a preparation method of the layered cobaltosic oxide material.
The application of the layered cobaltosic oxide material in the preparation of lithium ion batteries is also within the protection scope of the application.
Compared with the prior art, the application has the beneficial effects that:
the layered cobaltosic oxide material provided by the application has a multilayer loose and compact layered structure inside, is stable and ordered in structure and uniform in appearance, is used for preparing lithium ion batteries, and can improve the cycle stability of battery materials.
Drawings
Fig. 1 is a schematic structural diagram of a layered cobaltosic oxide material prepared in the example, wherein: 1-a first loose layer, 2-a first dense layer, 3-a second loose layer and 4-a second dense layer;
fig. 2 is an SEM image of the layered tricobalt tetraoxide material prepared in the examples.
Fig. 3 is a cross-sectional SEM image of the layered tricobalt tetraoxide material prepared in example 1.
Fig. 4 is a cross-sectional SEM image of the tricobalt tetraoxide material prepared in comparative example 1.
Description of the main reference signs
First loose layer 1
First dense layer 2
Second loose layer 3
Second dense layer 4
Detailed Description
The application is further illustrated below with reference to examples. These examples are only for illustrating the present application and are not intended to limit the scope of the present application. The experimental procedures in the examples below, without specific details, are generally performed under conditions conventional in the art or recommended by the manufacturer; the raw materials, reagents and the like used, unless otherwise specified, are those commercially available from conventional markets and the like. Any insubstantial changes and substitutions made by those skilled in the art in light of the above teachings are intended to be within the scope of the application as claimed.
An embodiment of the application provides a layered cobaltosic oxide material, which comprises a plurality of loose layers and a plurality of compact layers, wherein the loose layers and the compact layers are overlapped from inside to outside, the loose layers are positioned at the center, the compact layers are positioned at the outermost layers, and the density of the loose layers is smaller than that of the compact layers.
The cobaltosic oxide is used as a matrix of the lithium cobalt oxide positive electrode material, and the internal structure of the cobaltosic oxide positive electrode material can influence the structure of lithium cobalt oxide particles, so that the electrochemical performance of a lithium ion battery is influenced. In the lithium ion battery, the loose structure can shorten the diffusion distance of lithium ions, is favorable for removing and embedding lithium ions in the charge and discharge process, has small damage to the structure and is favorable for improving the cycle performance of the material. However, too loose structure of the positive electrode material results in poor pressure resistance, fragile rolling, structural damage and cycle deterioration.
The application provides a layered cobaltosic oxide material with multiple layers of loose and compact interphase, the layered structure has higher crystallinity, the loose and compact interphase layered structure is beneficial to improving the compression resistance of the material, wherein the loose structure can improve the diffusion performance of lithium ions, and the compact layer can maintain the structural stability of the material, so that the electrochemical performance of the material is improved.
In the embodiment, the granularity of the layered cobaltosic oxide material is 12-18 mu m, the porosity is 5-30%, and the true density is 5.94-6.09 g/cm 3 。
When the granularity of the cobaltosic oxide material is 12-14 mu m, the particle radius is smaller while other performances of the material are ensured, and the lithium ion diffusion is facilitated, and the cobaltosic oxide material is mainly applied to quick-charging materials; when cobaltosic oxideWhen the granularity of the material is 14-18 mu m, the high-temperature cycle performance of the positive electrode material is improved, and the electrochemical performance of the material under high voltage is improved. The porosity is 5-30%, and the true density is 5.94-6.09 g/cm 3 In the process, the crystallinity is improved in the sintering process, which is beneficial to optimizing the electrochemical performance of the anode material.
Fig. 1 is a schematic structural diagram of a layered cobaltosic oxide material provided by the present application, and it can be seen from the figure that the layered cobaltosic oxide material sequentially includes, from inside to outside, a first porous layer 1, a first dense layer 2, a second porous layer 3, and a second dense layer 4.
In the present embodiment, the first porous layer 1 has a thickness of 2 to 4 μm, a porosity of 10 to 35%, and a true density of 5.94 to 6.0g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the first compact layer 2 is 1-3 mu m, the porosity is 0.8-4%, and the true density is 6.05-6.09 g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the second loose layer 3 is 0.1-0.5 mu m, the porosity is 8-20%, and the true density is 6.01-6.04 g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the second compact layer 4 is 2-5 mu m, the porosity is 1-5%, and the true density is 6.04-6.07 g/cm 3 。
In the application, the porosity refers to the percentage value of the volume of all pores in the bulk material to the total volume of the material in a natural state. The porosity of the material directly reflects the compactness of the material, and if the porosity of the material is low, the compactness is high, otherwise, the porosity of the material is high, and if the porosity of the material is low, the compactness is low, and the inside of the material is loose. The principle of the porosity test in this patent is: and carrying out ion grinding cutting (such as argon ion beam cutting) on the granular material to obtain a flatter and clear material internal section electron microscope image, and carrying out automatic intelligent identification on the material section electron microscope image by using image processing software to obtain the porosities of various layer areas such as a plurality of loose layers, dense layers and the like in the material.
The true density refers to the ratio of the actual mass of the bulk material to the volume of the material (excluding the open pore volume of the material), and is a test value obtained by analysis by a true densitometer, and the test gas used by the true densitometer is helium. The working principle of the true density instrument is to apply an Archimedes principle-gas displacement method, according to the formula PV=nRT (Bohr's law), under certain conditions, small molecular (small diameter) inert gas is utilized to enter the interior of a material to open pores, the true volume (also called skeleton volume) of the sample is accurately measured by measuring the change of the gas capacity of the sample bin caused by the sample being placed in the sample bin, and the true mass of the material and the skeleton volume of the material are subjected to division operation to obtain the true density.
The layered cobaltosic oxide material provided by the application has the advantages that the internal structure is regular and orderly, the multiple compact layers and the loose layers are orderly arranged, the true density is higher, the porosity is higher, and the improvement of the cycle performance of the battery anode material and the energy density of the lithium ion battery is facilitated.
In this embodiment, a method for preparing the layered cobaltosic oxide material is further provided, including the following steps:
s1: adding water as a base solution into a reaction kettle, adding 200kg of cobalt carbonate as seed crystals, adjusting the granularity of the seed crystals to 8-14 mu m, and adjusting the pH to 7.5-8.5; adding cobalt salt solution, soluble metal salt solution and precipitant solution into a reaction kettle in parallel flow, wherein the feeding flow ratio of the cobalt salt solution to the precipitant solution to the soluble metal salt solution is (10-20): (20-32): 1; wherein, the feeding flow rate of the initial cobalt salt solution is 25-30 g/L, after 5-25 h, the feeding flow rate of the cobalt salt solution is adjusted to 5-25 g/L, after 15-40 h, the feeding flow rate of the cobalt salt solution is adjusted to 65g/L; simultaneously, the feeding flow rates of the precipitant solution and the soluble metal salt solution are adjusted proportionally;
s2: aging, filtering and washing a product obtained after the coprecipitation reaction in the step S1 is completed;
s3: calcining the product obtained in the step S2 under the atmosphere, wherein the calcining process comprises a drying section: the temperature is 150-200 ℃; and (3) pyrolysis section: the temperature is 200-300 ℃; high-temperature oxidation crystallization section: the temperature is 350-750 ℃, and the layered cobaltosic oxide material is obtained after calcination.
Although the lithium cobaltate material has the advantages of high voltage, stable structure, good cycle stability and the like, when more than 50% of lithium is removed by charging, irreversible phase transformation can occur, so that the cycle performance and the safety performance of the lithium ion battery are affected. The main method adopted at present is to dope metal element (mainly aluminum) and stabilize the structure of lithium cobaltate by utilizing the stability of the metal element in the charge and discharge process. However, in the process of preparing the doped cobaltosic oxide by adopting coprecipitation, the stacking order of the cobaltosic oxide is poor due to the existence of metal elements, loose particles with low tap density are easy to form, and the structural stability is poor.
The application initially forms a first porous layer inside by feeding the components in a gradient co-current manner; the reaction time is controlled, the feeding flow is changed, after the flow is regulated, the growth speed of particles is increased, after a period of time is caused by the change of the growth speed of the inner layer and the outer layer, the gaps on the surfaces of the particles are filled up to become compact (a first compact layer), at the moment, the growth speed is increased, primary particles are thinned and stacked on the surfaces to form a loose structure (a second loose layer), and along with the increase of the solid content in a reaction system, the surfaces of the primary particles become more compact (the second compact layer). Then, by regulating and controlling the calcination atmosphere, the seed crystal of the loose layer grows faster, the structure is loose, the primary particle spacing in the loose layer is large, the calcination shrinkage is serious, a larger loose layer is formed, the primary particles in the compact layer are compact in small structure in the precipitation process, and the layered cobaltosic oxide material with a compact structure is obtained by calcination.
In this embodiment, the cobalt salt is at least one of cobalt nitrate, cobalt sulfate or cobalt chloride; the soluble metal salt is at least one of nickel salt, manganese salt, aluminum salt, magnesium salt, calcium salt, zirconium salt or yttrium salt; the precipitant is at least one of ammonium bicarbonate, ammonia water or urea.
In this embodiment, the concentrations of the cobalt salt solution, the soluble metal salt solution, and the precipitant solution are 110 to 150g/L, 20 to 40g/L, and 140 to 200g/L, respectively.
In the embodiment, the temperature of the coprecipitation reaction in S1 is 45-55 ℃, and the precipitation time is 85-105 hours; the aging time in S2 is 2 hours.
In this embodiment, the temperature of the washing in S2 is 20 to 60 ℃; washed to TDS (dissolved total solids) < 50ppm.
In this embodiment, the atmosphere of the drying section and the pyrolysis section in S3 is one of nitrogen or helium; the atmosphere of the high-temperature oxidation crystallization section is air or oxygen.
Further, the calcination atmosphere is in a low pressure or negative pressure state.
The preparation and properties of the layered tricobalt tetraoxide material of the present application are described below using specific examples and comparative examples.
It should be noted that the feeding flow rate of the solution in the present application is limited to the used device, and is not limited to a specific value, and the solution can be implemented by other devices corresponding to different gradient feeding flows.
Example 1
The preparation method of the layered cobaltosic oxide material comprises the following steps:
s1: preparing 20g/L aluminum sulfate solution, 100g/L cobalt chloride solution and 130g/L ammonium bicarbonate solution by adopting deionized water;
s2: adding 200L of deionized water as a base solution into a reaction system, adding 200kg of cobalt carbonate as seed crystals, adjusting the granularity of the seed crystals to about 10 mu m, and adjusting the pH to 8.0; then, the prepared cobalt chloride solution, ammonium bicarbonate solution and aluminum sulfate solution are added into a reaction kettle simultaneously in a parallel flow feeding mode, and the feeding flow ratio of the cobalt chloride solution to the ammonium bicarbonate solution to the aluminum sulfate solution is 12:23.8:1; the temperature of the reaction kettle is 48 ℃, and the stirring speed is 280r/min; in the feeding process, the feeding flow of the cobalt chloride solution is gradually increased, the initial cobalt chloride solution flow is 30L/h, and after 24 hours of feeding, the cobalt chloride solution flow is adjusted to 48L/h; after 40 hours of feeding, the flow rate of the cobalt chloride solution is adjusted to 65L/h; the feed flow rates of the corresponding ammonium bicarbonate solution and aluminum sulfate solution are synchronously adjusted according to the proportion, and the reaction is stopped after 95 hours;
s3: transferring the product of the coprecipitation reaction in the S2 into an ageing tank for ageing for 2 hours, then carrying out salt-free water washing at 50 ℃ in a centrifuge, and washing for 6 times, 1m each time 3 Washing until the TDS of washing water is less than 50 ppm;
s4: and (3) carrying out sectional calcination on the product washed in the step (S3), wherein the step of drying: calcining at 200deg.C for 2 hr without opening air pressure; and (3) pyrolysis section: calcining at 300 ℃ for 3 hours without opening air pressure; high-temperature oxidation crystallization section: calcining at 740 ℃ for 1h, and opening the air pressure to a proper atmosphere to obtain the layered cobaltosic oxide material.
Fig. 2 and 3 are SEM cross-sectional views of the layered cobaltosic oxide material prepared in example 1, respectively, and it can be seen from the figures that the prepared layered cobaltosic oxide material is in a regular sphere shape, the particle size is about 18 μm, the interior of the material particles has a regular and ordered layered structure, the boundary between each layer is obvious, and a first loose layer, a first dense layer, a second loose layer and a second dense layer are sequentially arranged from inside to outside. Table 1 shows the physical and chemical properties of the layered tricobalt tetraoxide material prepared in example 1.
Table 1 physicochemical properties of the layered tricobalt tetraoxide material prepared in example 1
Example 2
The preparation method of the layered cobaltosic oxide material comprises the following steps:
s1: preparing 40g/L aluminum nitrate solution, 150g/L cobalt sulfate solution and 180g/L ammonium bicarbonate solution by adopting deionized water;
s2: adding 200L of deionized water as a base solution into a reaction system, adding 200kg of cobalt carbonate as seed crystals, adjusting the granularity of the seed crystals to about 12 mu m, and adjusting the pH to 7.5; then, the prepared cobalt nitrate solution, ammonium bicarbonate solution and aluminum sulfate solution are added into a reaction kettle simultaneously in a parallel flow feeding mode, and the feeding flow ratio of the cobalt sulfate solution to the ammonium bicarbonate solution to the aluminum nitrate solution is 10:22:1; the temperature of the reaction kettle is 50 ℃, and the stirring speed is 280r/min; in the feeding process, the feeding flow of the cobalt salt solution is gradually increased, the initial cobalt flow is 30L/h, and after 15 hours of feeding, the cobalt salt flow is adjusted to 48L/h; after 30 hours of feeding, the flow rate of the cobalt sulfate solution is adjusted to 65L/h; the feed flow rates of the corresponding ammonium bicarbonate solution and aluminum nitrate solution are synchronously adjusted according to the proportion, and the reaction is stopped after 105 hours;
s3: transferring the product of the coprecipitation reaction in the S2 into an ageing tank for ageing for 2 hours, then carrying out salt-free water washing at 50 ℃ in a centrifuge, and washing for 6 times, 1m each time 3 Washing until the TDS of washing water is less than 50 ppm;
s4: and (3) carrying out sectional calcination on the product washed in the step (S3), and drying: calcining at 200 ℃ for 1h without opening air pressure; and (3) pyrolysis section: calcining at 300 ℃ for 4 hours without opening air pressure; high-temperature oxidation crystallization section: calcining at 740 ℃ for 1.5h, and opening the air pressure to ensure proper atmosphere to obtain the layered cobaltosic oxide material.
The layered tricobalt tetroxide material prepared in example 2 is substantially similar in morphology and structure to that of example 1, and the physicochemical properties of the layered tricobalt tetroxide material prepared in example 2 are shown in table 2.
Table 2 physicochemical properties of layered tricobalt tetraoxide material prepared in example 2
Example 3
A layered cobaltosic oxide material and a preparation method thereof, wherein the method comprises the following steps:
s1: preparing 30g/L aluminum sulfate solution, 120g/L cobalt chloride solution and 160g/L ammonium bicarbonate solution by adopting deionized water;
s2: adding 200L of deionized water as a base solution into a reaction system, adding 200kg of cobalt carbonate as seed crystals, adjusting the granularity of the seed crystals to about 14 mu m, and adjusting the pH to 8.2; then, the prepared cobalt chloride solution, ammonium bicarbonate solution and aluminum sulfate solution are added into a reaction kettle simultaneously in a parallel flow feeding mode, and the feeding flow ratio of the cobalt chloride solution to the ammonium bicarbonate solution to the aluminum sulfate solution is 15:28:1; the temperature of the reaction kettle is 52 ℃, and the stirring speed is 280r/min; in the feeding process, the feeding flow of the cobalt chloride solution is gradually increased, the initial cobalt flow is 25L/h, and after 12 hours of feeding, the flow of the cobalt chloride solution is adjusted to 45L/h; after 24 hours of feeding, the flow rate of the cobalt chloride solution is adjusted to 65L/h; the feed flow rates of the corresponding ammonium bicarbonate solution and aluminum sulfate solution are synchronously adjusted according to the proportion, and the reaction is stopped after 100 hours;
s3: transferring the product of the coprecipitation reaction in the S2 into an ageing tank for ageing for 2 hours, then carrying out salt-free water washing at 50 ℃ in a centrifuge, and washing for 6 times, 1m each time 3 Washing until the TDS of washing water is less than 50 ppm;
s4: carrying out sectional calcination on the product washed in the step S3, wherein the calcination temperature is 300 ℃ for 3 hours, and opening nitrogen atmosphere; calcining at 720 ℃ for 2h, and opening the air pressure to a proper atmosphere to obtain the layered cobaltosic oxide material.
The layered tricobalt tetroxide material prepared in example 3 is substantially similar in morphology and structure to that of example 1, and the physicochemical properties of the layered tricobalt tetroxide material prepared in example 3 are shown in table 3.
TABLE 3 physicochemical Properties of the layered tricobalt tetraoxide Material prepared in example 3
Example 4
The preparation method of the layered cobaltosic oxide material comprises the following steps:
s1: preparing 25g/L of aluminum nitrate solution, 120g/L of cobalt sulfate solution and 140g/L of ammonium bicarbonate solution by adopting deionized water;
s2: adding 200L of deionized water as a base solution into a reaction system, adding 200kg of cobalt carbonate as seed crystals, adjusting the granularity of the seed crystals to about 8 mu m, and adjusting the pH to 8.5; then, the prepared cobalt sulfate solution, ammonium bicarbonate solution and aluminum nitrate solution are added into a reaction kettle simultaneously in a parallel flow feeding mode, and the feeding flow ratio of the cobalt sulfate solution to the ammonium bicarbonate solution to the aluminum nitrate solution is 16:30:1; the temperature of the reaction kettle is 48 ℃, and the stirring speed is 280r/min; in the feeding process, the feeding flow of the cobalt salt solution is gradually increased, the feeding flow of the initial cobalt sulfate solution is 25L/h, and after feeding for 6 hours, the feeding flow of the cobalt sulfate solution is adjusted to 45L/h; after 15 hours of feeding, the feeding flow rate of the cobalt sulfate solution is adjusted to 65L/h; the feed flow rates of the corresponding ammonium bicarbonate solution and aluminum nitrate solution are synchronously adjusted according to the proportion, and the reaction is stopped after 85 hours;
s3: transferring the product of the coprecipitation reaction in the S2 into an ageing tank for ageing for 2 hours, then carrying out salt-free water washing at 50 ℃ in a centrifuge, and washing for 6 times, 1m each time 3 Washing until the TDS of washing water is less than 50 ppm;
s3: carrying out sectional calcination on the product washed in the step S3, wherein the calcination temperature is 300 ℃ for 4 hours, and opening nitrogen atmosphere; calcining at 720 ℃ for 2h, and opening the air pressure to a proper atmosphere to obtain the layered cobaltosic oxide material.
The layered tricobalt tetroxide material prepared in example 4 is substantially similar in morphology and structure to that of example 1, and the physicochemical properties of the layered tricobalt tetroxide material prepared in example 4 are shown in table 4.
Table 4 physicochemical properties of layered tricobalt tetraoxide material prepared in example 4
Comparative example 1
The preparation method of the large-granularity cobaltosic oxide material comprises the following steps:
s1: preparing 20g/L aluminum nitrate solution, 100g/L cobalt sulfate solution and 130g/L ammonium bicarbonate solution by adopting deionized water;
s2: adding 200L of deionized water as a base solution into a reaction kettle, adding 200kg of cobalt carbonate as seed crystals, adjusting the granularity of the seed crystals to about 10 mu m, and adjusting the pH value to 8.0; then the prepared cobalt sulfate solution, ammonium bicarbonate solution and aluminum nitrate solution are added into a reaction kettle simultaneously in a parallel flow feeding mode, the temperature of the reaction kettle is controlled to be 48 ℃, the stirring speed is 280r/min, the feeding flow of the cobalt sulfate solution is 45L/h for feeding, the ammonium bicarbonate flow is 89.5L/h, the feeding flow of the aluminum nitrate solution is 3.75L/h, the feeding flow ratio of the cobalt sulfate solution, the ammonium bicarbonate and the aluminum nitrate solution is 12:23.8:1), and the reaction is stopped after 95 h;
s3: transferring the product of the coprecipitation reaction in the S2 into an ageing tank for ageing for 2 hours, then carrying out salt-free water washing at 50 ℃ in a centrifuge, and washing for 6 times, 1m each time 3 Washing until the TDS of washing water is less than 50 ppm;
s4: and (3) carrying out sectional calcination on the product washed in the step (S3), and drying: calcining at 200deg.C for 2 hr without opening air pressure; and (3) pyrolysis section: calcining at 300 ℃ for 3 hours without opening air pressure; high-temperature oxidation crystallization section: calcining at 740 ℃ for 1h, and opening the air pressure to a proper atmosphere to obtain the layered cobaltosic oxide material.
The layered cobaltosic oxide material prepared in comparative example 1 was in the form of a regular sphere having a particle size of about 18 μm, a porosity of 12% and a true density of 6.03g/cm 3 . Fig. 4 is a cross-sectional SEM image of the cobaltosic oxide material prepared in comparative example 1, and it can be seen from the image that the prepared cobaltosic oxide material has a uniform and compact internal structure, a compact internal structure and a loose external side, and has no obvious layered structure between the loose and compact phases of the material in the application.
Performance testing
Lithium carbonate is added into the cobaltosic oxide materials prepared in the example 1 and the comparative example 1 according to the same technological conditions for secondary sintering to prepare a lithium cobaltate positive electrode material, acetylene black and polyvinylidene fluoride (PVDF) are respectively added into the positive electrode material, the mixture is uniformly mixed and ground into uniform slurry, the uniform slurry is coated on an aluminum foil to prepare a positive electrode, a metal lithium sheet is used as a negative electrode, and LiPF6 is used as electrolyte to prepare the button cell. Electrochemical test voltage was 4.53V, 1C high temperature cycle test was performed at 50 ℃, and test results are shown in table 5:
TABLE 5 electrochemical Properties of example 1 and comparative example 1
| Performance of | Retention of 48 cycles | Retention of 66 cycles |
| Example 1 | 90.2％ | 79.9％ |
| Comparative example 1 | 84.2％ | 70.8％ |
From the results, the layered cobaltosic oxide prepared by the method has higher cycle retention rate under the same condition than the cobaltosic oxide material with a conventional structure. In addition, the preparation process is simple, convenient to operate and easy for industrial production.
Finally, it should be noted that the above-mentioned embodiments are merely for illustrating the technical solution of the present application and not for limiting the same, and although the present application has been described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications and equivalents may be made to the technical solution of the present application without departing from the spirit and scope of the technical solution of the present application.
Claims (7)
1. The layered cobaltosic oxide material is characterized by comprising a plurality of loose layers and a plurality of compact layers, wherein the loose layers and the compact layers are overlapped from inside to outside, the loose layers are positioned at the center, the compact layers are positioned at the outermost layers, and the density of the loose layers is smaller than that of the compact layers;the layered cobaltosic oxide material sequentially comprises a first loose layer, a first compact layer, a second loose layer and a second compact layer from inside to outside, wherein the thickness of the first loose layer is 2-4 mu m, the porosity is 10% -35%, and the true density is 5.94-6.0 g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the first compact layer is 1-3 mu m, the porosity is 0.8% -4%, and the true density is 6.05-6.09 g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the second loose layer is 0.1-0.5 mu m, the porosity is 8% -20%, and the true density is 6.01-6.04 g/cm 3 The method comprises the steps of carrying out a first treatment on the surface of the The thickness of the second compact layer is 2-5 mu m, the porosity is 1% -5%, and the true density is 6.04-6.07 g/cm 3 。
2. A method for preparing the layered tricobalt tetraoxide material according to claim 1, comprising the steps of:
s1: adding water as a base solution into a reaction kettle, adding 200kg cobalt carbonate as seed crystals, adjusting the granularity of the seed crystals to 8-14 mu m, and adjusting the pH to 7.5-8.5; adding cobalt salt solution, soluble metal salt solution and precipitant solution into a reaction kettle in parallel flow, wherein the feeding flow ratio of the cobalt salt solution to the precipitant solution to the soluble metal salt solution is (10-20): (20-32): 1; wherein the initial feeding flow rate of the cobalt salt solution is 25-30 g/L, after 5-25 h, the feeding flow rate of the cobalt salt solution is adjusted to 5-25 g/L, and after 15-40 h, the feeding flow rate of the cobalt salt solution is adjusted to 65g/L; simultaneously, the feeding flow rates of the precipitant solution and the soluble metal salt solution are adjusted proportionally;
s2: aging, filtering and washing a product obtained after the coprecipitation reaction in the step S1 is completed;
s3: calcining the product obtained in the step S2 under the atmosphere, wherein the calcining process comprises a drying section: the temperature is 150-200 ℃; and (3) pyrolysis section: the temperature is 200-300 ℃; high-temperature oxidation crystallization section: the temperature is 350-750 ℃, and the layered cobaltosic oxide material is obtained after calcination.
3. The method of claim 2, wherein the cobalt salt is at least one of cobalt nitrate, cobalt sulfate, or cobalt chloride; the soluble metal salt is at least one of nickel salt, manganese salt, aluminum salt, magnesium salt, calcium salt, zirconium salt or yttrium salt; the precipitant is at least one of ammonium bicarbonate, ammonia water or urea.
4. The method of claim 2, wherein the cobalt salt solution, the soluble metal salt solution, and the precipitant solution have concentrations of 110 to 150g/L, 20 to 40g/L, and 140 to 200g/L, respectively.
5. The preparation method of claim 2, wherein the temperature of the coprecipitation reaction in S1 is 45-55 ℃, and the precipitation time is 85-105 hours; the aging time in S2 is 2 hours.
6. The method of claim 2, wherein the atmosphere of the drying section and the pyrolysis section in S3 is nitrogen or helium; the atmosphere of the high-temperature oxidation crystallization section is air or oxygen.
7. Use of the layered tricobalt tetraoxide material according to claim 1 for the preparation of a lithium ion battery.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004010375A (en) * | 2002-06-04 | 2004-01-15 | Nippon Chem Ind Co Ltd | Processes for preparing tricobalt tetraoxide and lithium cobaltate |
| CN102701292A (en) * | 2012-05-30 | 2012-10-03 | 西北矿冶研究院 | Preparation method of cobalt carbonate material with compact structure and spheroid shape |
| CN112125350A (en) * | 2019-06-24 | 2020-12-25 | 荆门市格林美新材料有限公司 | Aluminum-doped cobaltosic oxide with multilayer core-shell structure and preparation method thereof |
| CN112607791A (en) * | 2020-11-19 | 2021-04-06 | 北京泰丰先行新能源科技有限公司 | Precursor for lithium ion battery with multilayer structure, positive electrode material and preparation method of precursor |
| CN112723422A (en) * | 2020-12-30 | 2021-04-30 | 湖南杉杉能源科技股份有限公司 | Aluminum-doped cobaltosic oxide core-shell material and preparation method thereof |
| CN112928250A (en) * | 2021-01-22 | 2021-06-08 | 厦门厦钨新能源材料股份有限公司 | Nickel-cobalt-manganese ternary material and precursor thereof, and preparation method and application thereof |
-
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- 2021-12-24 CN CN202111609616.5A patent/CN114249355B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004010375A (en) * | 2002-06-04 | 2004-01-15 | Nippon Chem Ind Co Ltd | Processes for preparing tricobalt tetraoxide and lithium cobaltate |
| CN102701292A (en) * | 2012-05-30 | 2012-10-03 | 西北矿冶研究院 | Preparation method of cobalt carbonate material with compact structure and spheroid shape |
| CN112125350A (en) * | 2019-06-24 | 2020-12-25 | 荆门市格林美新材料有限公司 | Aluminum-doped cobaltosic oxide with multilayer core-shell structure and preparation method thereof |
| CN112607791A (en) * | 2020-11-19 | 2021-04-06 | 北京泰丰先行新能源科技有限公司 | Precursor for lithium ion battery with multilayer structure, positive electrode material and preparation method of precursor |
| CN112723422A (en) * | 2020-12-30 | 2021-04-30 | 湖南杉杉能源科技股份有限公司 | Aluminum-doped cobaltosic oxide core-shell material and preparation method thereof |
| CN112928250A (en) * | 2021-01-22 | 2021-06-08 | 厦门厦钨新能源材料股份有限公司 | Nickel-cobalt-manganese ternary material and precursor thereof, and preparation method and application thereof |
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