CN110854383A - Modified ternary cathode material and preparation method thereof - Google Patents
Modified ternary cathode material and preparation method thereof Download PDFInfo
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Abstract
The invention discloses a modified ternary cathode material and a preparation method thereof. The method for preparing the modified ternary cathode material comprises the following steps: (1) mixing a rare earth coating agent with water to form an unsaturated solution containing a coating agent element to obtain a coating solution; (2) mixing the coating solution with a ternary cathode material to perform wet coating treatment so as to form a uniform and consistent coating layer on the surface of the ternary cathode material to obtain a coating mixed material modified material; and (3) carrying out post-treatment processes such as sintering and the like on the coating mixed material to obtain the modified ternary cathode material. According to the method, the rare earth coating agent is used for carrying out wet coating modification on the ternary cathode material, the coating uniformity of the coating agent is high, the modified product has higher cycle stability and rate capability, and the method is simple and efficient and is suitable for industrial popularization.
Description
Technical Field
The invention relates to the technical field of lithium batteries, in particular to a modified ternary cathode material and a preparation method thereof.
Background
At present, ternary materials (LiNi)xCoyM1-x-yO2，0.3<x<1，0<y<1，x+y<1) Is the preferred anode material of the high energy density power battery. However, ternary materials (especially high-nickel ternary materials) have many intrinsic disadvantages, such as poor cycle stability due to cyclic phase change under high voltage, poor rate performance due to low electron conductivity and Li/Ni mixed discharge, and Ni in high lithium removal state4+Is prone to reduction to Ni3+And the release of oxygen causes the problems of the reduction of the thermal stability and the safety performance of the battery core and the like. In response to the above problems, doping and uniform surface coating are important methods for improving and stabilizing the ternary properties of high nickel.
The ternary material, especially the high nickel ternary material, has cation mixed discharge, secondary ball cracking, material pulverization, side reaction between the anode material and the electrolyte, formation of rock salt phase and the like in the long-term circulation process. The surface dry coating or wet coating after crushing the original material is some existing solutions in the market at present, but the dry coating has poor uniformity and unstable coating agent, the increase of direct current internal resistance of the battery cell can be brought by the coating of oxides (aluminum oxide, zirconium oxide and the like), the wet coating after crushing the material can lead the original material to generate lithium source loss by adding a complexing agent and sintering the materials to be combined together again, the complexing agent further introduces surface residual alkali and impurities, the cycle performance of the materials combined by secondary sintering is far lower than that of the materials which are not crushed (cracking is easy to occur at the crushing position in the cycle process), therefore, the method is still in the laboratory research stage and is not suitable for mass production at present.
According to the classification of crystal forms, the ternary material can be divided into a single crystal material and a polycrystal material (secondary ball), wherein the porous structure of secondary ball particles increases the lithium embedding amount, is favorable for the infiltration of electrolyte, shortens the diffusion path of lithium ions, and is an important condition for realizing high multiplying power and high capacity of a battery cell. Meanwhile, the larger specific surface area increases the side reaction between the anode material and the electrolyte, and particularly provides better generation conditions for side reaction and cation mixed discharge under the high oxidation state of fully charged battery cells; the single crystal material is characterized by stable structure and difficult cracking in the circulating process, but experiments show that the phenomenon of microcracking and cracking of the single crystal material in the long-term circulating process is caused by rapid lithium ion deintercalation, and the cation mixed discharging condition of the single crystal material cannot be reduced due to the single crystal structure.
The material suppliers are also currently solving and optimizing the problems of high nickel ternary materials, such as the above mentioned oxide coating, which mainly serves to improve the cycling and cell safety performance, but this method is not suitable for mass production because ternary materials are moisture sensitive and Al is in the nanometer size2O3For example, the material has a large specific surface area and is very easy to absorb water, the water absorption of the ternary material is increased after dry coating, the difficulty of pulping of the material is greatly improved (slurry gel is caused by the fact that residual alkali destroys glue solution due to overhigh water content), and the direct current internal resistance problem which is most concerned by a whole vehicle factory is brought.
In summary, the conventional ternary cathode material and the preparation method thereof still need to be improved.
Disclosure of Invention
The present invention is directed to solving, at least to some extent, one of the technical problems in the related art. To this end, an object of the present invention is to propose a method for preparing a modified ternary cathode material and a modified ternary cathode material prepared by the method. According to the method, the rare earth coating agent is used for carrying out wet coating modification on the ternary cathode material, the coating uniformity of the coating agent is high, the modified product has higher rate performance and cycle stability, and the method is simple and efficient and is suitable for industrial popularization.
In one aspect of the invention, a method of preparing a modified ternary cathode material is presented. According to an embodiment of the invention, the method comprises: (1) mixing a rare earth coating agent with water to obtain a coating solution; (2) carrying out wet coating treatment on the coating liquid and the ternary cathode material so as to form a coating layer on at least part of the surface of the ternary cathode material to obtain a coating mixed material; and (3) sintering the coating mixed material to obtain the modified ternary cathode material.
According to the method for preparing the modified ternary cathode material, disclosed by the embodiment of the invention, the ternary cathode material is coated by a wet method through a coating liquid obtained by mixing the rare earth coating agent and water, so that the coating uniformity of the coating agent on the surface of the ternary cathode material can be obviously improved, the rare earth element can enter the internal crystal lattice of the ternary cathode material to fill crystal lattice vacancies through sintering treatment while the occurrence of side reactions between the ternary cathode material and an electrolyte can be reduced, the cation mixed discharge of electrons in a fully charged high oxidation state is inhibited, the transmission efficiency of the electrons in a battery cell is improved based on the characteristics of an outer-layer electron structure of the rare earth element, the de-intercalation rate of lithium ions in the cathode material is further improved, and the electrochemical properties such as the rate capability, the capacity retention rate and the like of the battery cell are obviously improved.
In addition, the method for preparing the modified ternary cathode material according to the above embodiment of the present invention may further have the following additional technical features:
in some embodiments of the invention, the rare earth capping agent comprises at least one selected from the group consisting of gadolinium salts, terbium salts, lanthanum salts, cerium salts, and neodymium salts.
In some embodiments of the present invention, the mass ratio of the rare earth coating agent to the water is (2-4): 30-60.
In some embodiments of the invention, the ternary cathode material is a nickel-cobalt-manganese ternary cathode material or a nickel-cobalt-aluminum ternary cathode material.
In some embodiments of the invention, the rare earth coating agent accounts for 0.5-2% mol of the total mass of the coating mixture.
In some embodiments of the invention, the wet coating treatment comprises a first mixing treatment and a second mixing treatment which are sequentially performed, wherein the first mixing treatment is performed at a rotating speed of 20-40 r/min for 5-10 min, and the second mixing treatment is performed at a rotating speed of 50-80 r/min for 20-45 min.
In some embodiments of the invention, the sintering process comprises: and heating the coating material to 700-900 ℃ at a heating rate of 2-4 ℃/min in an oxidizing atmosphere, and preserving heat for 3-6 h.
In some embodiments of the present invention, before the step (3), the drying process is further performed on the coating material mixture.
In some embodiments of the present invention, the drying treatment is performed at 120 to 180 ℃.
In another aspect of the invention, a modified ternary cathode material is provided. According to the embodiment of the invention, the modified ternary cathode material is prepared by the method for preparing the modified ternary cathode material in the embodiment. Therefore, the surface of the modified ternary cathode material is uniformly coated by a wet method to obtain a rare earth element coating layer, and partial rare earth element bulk phase doping is realized in the original ternary cathode material by high-temperature sintering, so that the modified ternary cathode material has better performances such as electron transmission efficiency, and a battery cell adopting the modified ternary cathode material has better electrochemical performances such as rate performance, capacity retention rate and the like.
Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
Drawings
The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:
fig. 1 is a schematic flow diagram of a method of preparing a modified ternary cathode material according to one embodiment of the present invention;
FIG. 2 is an SEM image of the modified ternary cathode material prepared in example 1;
FIG. 3 is a SEM-EDX surface scanning spectrum of the modified ternary cathode material prepared in example 1;
fig. 4 is an EDS layered image of the modified ternary cathode material prepared in example 1;
fig. 5 is an EDS spectrum of the modified ternary cathode material prepared in example 1;
fig. 6 is a graph of cycle testing of cells made from the materials of example 1 and comparative example 3.
Detailed Description
The following describes embodiments of the present invention in detail. The following examples are illustrative only and are not to be construed as limiting the invention. The examples, where specific techniques or conditions are not indicated, are to be construed according to the techniques or conditions described in the literature in the art or according to the product specifications. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products commercially available.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.
In one aspect of the invention, a method of preparing a modified ternary cathode material is presented. According to an embodiment of the invention, the method comprises: (1) mixing a rare earth coating agent with water to obtain a coating solution; (2) carrying out wet coating treatment on the coating liquid and the ternary cathode material so as to form a coating layer on at least part of the surface of the ternary cathode material to obtain a coating mixed material; and (3) sintering the coating mixed material to obtain the modified ternary cathode material.
According to the method for preparing the modified ternary cathode material, disclosed by the embodiment of the invention, the ternary cathode material is coated by a wet method through a coating liquid obtained by mixing the rare earth coating agent and water, so that the coating uniformity of the coating agent on the surface of the ternary cathode material can be obviously improved, the rare earth element can enter the internal crystal lattice of the ternary cathode material to fill crystal lattice vacancies through sintering treatment while the occurrence of side reactions between the ternary cathode material and an electrolyte can be reduced, the cation mixed discharge of electrons in a fully charged high oxidation state is inhibited, the transmission efficiency of the electrons in a battery cell is improved based on the characteristics of an outer-layer electron structure of the rare earth element, the de-intercalation rate of lithium ions in the cathode material is further improved, and the electrochemical properties such as the rate capability, the capacity retention rate and the like of the battery cell are obviously improved.
In addition, the method for preparing the modified ternary cathode material provided by the invention does not crush the ternary cathode material and does not additionally use additives such as complexing agents and the like. The inventor finds that in the existing technical scheme related to modification of the ternary cathode material, the commercially available ternary cathode material is generally crushed and then subjected to subsequent treatment. After the material is crushed, the specific surface area of the material is increased, but more lithium source is lost in the wet coating process, and the telecommunication capacity is reduced. In addition, after the crushed material is sintered, the material appearance is extremely irregular, the material is extremely easy to crush in the rolling stage of electric core manufacturing, the capacity of the electric core is reduced, the electric core is weak in structure, the crushing is easy to occur in the circulating process, and the capacity is greatly attenuated. On the other hand, no complexing agent is used in the preparation method, so that new surface residual alkali and impurities can be effectively prevented from being introduced into the material, and the improvement of the material performance is further facilitated.
The method of preparing the modified ternary cathode material according to the embodiment of the present invention is further described in detail below. Referring to fig. 1, according to an embodiment of the invention, the method comprises:
s100: obtaining a coating solution
In this step, a rare earth coating agent is mixed with water to form an unsaturated solution containing a rare earth element, i.e., a coating solution.
According to some embodiments of the invention, the rare earth capping agent comprises at least one selected from the group consisting of a gadolinium salt, a terbium salt, a lanthanum salt, a cerium salt, and a neodymium salt. The source method of the rare earth coating agent is cheap and easy to obtain, and can provide the required rare earth elements for the coating modification of the ternary cathode material. Specifically, specific examples of the above lanthanum salt, gadolinium salt, terbium salt, neodymium salt include Gd (NO)3)3·6H2O、Tb(NO3)3·6H2O、Nd(NO3)3·6H2O、La(NO3)3·6H2O、···。
According to some embodiments of the present invention, the mass ratio of the rare earth cladding agent to water may be (2-4): 30-60. Specifically, the rare earth capping agent may be 2, 2.5, 3, 3.5, 4, etc. in parts by mass, and the water may be 30, 35, 40, 45, 50, 60, etc. in parts by mass. By controlling the proportion of the rare earth coating agent and the water within the range, the coating liquid can have proper concentration, viscosity and other properties, thereby being further beneficial to the coating of the rare earth element on the surface of the ternary cathode material.
S200: wet cladding process
In the step, the coating liquid and the unmodified ternary cathode material are subjected to wet coating treatment, so that a uniform coating layer is formed on at least part of the surface of the ternary cathode material, and a coating mixed material is obtained. Specifically, a proper amount of ternary cathode material can be put into a fusion coating machine, uniformly stirred and added with a coating solution for wet coating, so that a coating effect far higher than that of dry coating is obtained. According to the specific example of the invention, the ternary cathode material can be stirred for 1-2 min at a stirring speed of 20-40 r/min in advance, so that the ternary cathode material is uniformly distributed in the coating machine.
The specific kind of the unmodified ternary cathode material is not particularly limited, and a ternary cathode material commonly used in the art for lithium ion batteries may be used. In other words, the wet coating modification method proposed by the present invention does not specifically limit the specific kind of the ternary cathode material. According to some embodiments of the present invention, the ternary cathode material may be a nickel-cobalt-manganese ternary cathode material or a nickel-cobalt-aluminum ternary cathode material, such as NCM811, NCM622, NCA811, and the like. Therefore, the method provided by the invention is used for modifying the conventional ternary cathode material, and the electrochemical performance of the ternary cathode material can be obviously improved.
According to some embodiments of the present invention, the ratio of the coating solution to the ternary cathode material may be controlled such that the rare earth coating agent accounts for 0.5-2% mol of the total mass of the coating mixture, for example, 0.5% mol, 0.75% mol, 1.0% mol, 1.5% mol, 2.0% mol, and the like. Therefore, the doping proportion of the rare earth element in the obtained modified ternary cathode material is 1-3 wt%, and the modified ternary cathode material with better performance is obtained. In addition, the coating uniformity of the material is higher and the coating effect is better under the condition of proportioning the coating liquid and the ternary cathode material.
According to some embodiments of the present invention, the wet coating process includes a first mixing process performed at a rotation speed of 20 to 40r/min (e.g., 20r/min, 25r/min, 30r/min, 35r/min, 40r/min, etc.) for 5 to 10min (e.g., 5min, 6min, 7min, 8min, 10min, etc.), and a second mixing process performed at a rotation speed of 50 to 80r/min (e.g., 50r/min, 55r/min, 60r/min, 70r/min, 80r/min, etc.) for 20 to 45min (e.g., 20min, 25min, 30min, 35min, 45min, etc.). Therefore, the mixed materials containing the coating agent and the ternary cathode material are sequentially subjected to slow mixing and fast mixing, so that the mixed materials can keep a slurry state with good fluidity, and the coating effect is further improved.
S300: sintering treatment
In the step, the coating mixed material is sintered to obtain the modified ternary cathode material. Through sintering the coating mixed material, part of rare earth elements in the coating agent can enter the interior of the ternary cathode material and occupy space in the layered structure of the ternary cathode material, so that the effects of reducing cation mixed-row, improving the material multiplying power performance and the like are realized. Meanwhile, the surface of the material subjected to sintering treatment is still coated with the rare earth element coating layer, so that the occurrence of side reaction between the ternary cathode material and the electrolyte can be effectively reduced. Therefore, the method provided by the invention improves the performance of the ternary cathode material from the aspects of the interior and the surface of the material.
According to some embodiments of the invention, the sintering process comprises: and heating the coating material to 700-900 ℃ at a heating rate of 2-4 ℃/min in an oxidizing atmosphere, and preserving heat for 3-6 h. Specifically, the heating rate can be 2 ℃/min, 3 ℃/min, 4 ℃/min and the like, the heating target temperature can be 700 ℃, 750 ℃, 800 ℃, 850 ℃, 900 ℃ and the like, and the heat preservation time can be 3h, 4h, 5h, 6h and the like. By sintering under the above conditions, it is further facilitated that a part of rare earth elements in the coating agent enter the interior of the ternary cathode material, and the effects of improving cation mixing and electron transmission of the material are achieved. The oxidizing atmosphere is preferably carried out under an oxygen concentration of not less than 93%, whereby the sintering effect is more excellent.
According to some embodiments of the present invention, the method for preparing a modified ternary cathode material further comprises, before S300: and drying the coating mixed material.
According to some embodiments of the present invention, the drying process is performed at 120-180 ℃, such as 120 ℃, 130 ℃, 150 ℃, 170 ℃, 180 ℃. By carrying out drying treatment under the conditions, the dried material has fluidity similar to that of the uncoated ternary cathode material on the premise of ensuring higher drying efficiency. In addition, the drying process is not particularly limited as long as the material is completely dried, and it is expected that about 6 to 12 hours are required at 120 to 180 ℃.
Further, according to the embodiment of the present invention, after the sintering process is completed, the product may be crushed to a desired particle size according to actual needs, and then sieved, which is not described herein again.
In another aspect of the invention, a modified ternary cathode material is provided. According to the embodiment of the invention, the modified ternary cathode material is prepared by the method for preparing the modified ternary cathode material in the embodiment. Therefore, the surface of the modified ternary cathode material is uniformly coated by a wet method to obtain a rare earth element coating layer, and the interior of the ternary cathode material is doped with the rare earth element, so that the modified ternary cathode material has better performances such as electron transmission efficiency, and the like.
In addition, it should be noted that all the features and advantages described above for the "method for preparing a modified ternary cathode material" are also applicable to the "modified ternary cathode material", and are not described in detail herein.
The invention will now be described with reference to specific examples, which are intended to be illustrative only and not to be limiting in any way.
Example 1
1. Preparation, unopened 25 kg of high nickel ternary material, unopened Nd (NO)3)3·6H2O: 500g, and 50L of volume, and coating the required deionized water, electronic scale, beaker and other instruments;
2. accurately weighing 15 kg of NCM811 ternary material, adding the NCM811 ternary material into a fusion coating machine through a feed inlet, closing the feed inlet, starting slow stirring at the stirring speed of 30r/min for 2min to uniformly distribute the anode material in the fusion coating agent;
3. 6kg of deionized water was accurately weighed, and Nd (NO) was weighed as required3)3·6H2O was added to the deionized water (362g), and Nd (NO) was allowed to stand by stirring or standing for a long time3)3·6H2O is completely dissolved in deionized water to form Nd (NO) containing3)3·6H2An unsaturated solution of O;
4. nd (NO) is dissolved in a container such as a beaker3)3·6H2The solution of O is poured into a device to which a ternary material has been added, in which Nd (NO) is added3)3·6H2The adding amount of O accounts for 0.5 mol percent of the total proportion of the materials;
5. after the addition is finished, starting the equipment, firstly slowly mixing for 3min at the stirring speed of 20r/min, and then quickly mixing for 40min at the stirring speed of 70r/min, wherein the materials in the fusion machine are in a slurry state with better fluidity;
6. after the rapid mixing is finished, starting the heating function of the equipment, wherein the heating mode is oil bath heating, the heating temperature is 150 ℃, the heating is continuously carried out until the materials are completely dried, the expected time is 8 hours, and the state and the fluidity of the materials after the drying are similar to those of the original uncoated materials;
7. after drying, fixing the aluminum plastic film packaging bag at a material outlet of the fusion coating agent through a hoop, starting a discharging system of equipment, slowly discharging the materials from the equipment through a discharging pump for 3-5 min, immediately transferring the aluminum plastic film bag filled with the materials to a vacuum sealing machine for sealing after discharging is finished, and sealing the aluminum plastic film bag at the outer side in a vacuum mode;
8. sintering the materials, transferring the packaged sample in the step 7 to a positive electrode material sintering pilot line, loading the saggars among the material loading saggars, wherein the size of each saggar is 300(L) × 300(W) × 100(H) mm, loading 1.5-2.5 kg of materials into each saggar, and after all the saggars are loaded, partitioning the materials by adopting a scraper to prepare for sintering;
9. transferring the sagger to the inlet of the roller kiln, starting an oxygen generator, slowly introducing oxygen with the purity of more than or equal to 93% into the roller kiln, and gradually discharging the original air in the roller kiln;
10. setting the temperature of the roller kiln, wherein the overall length of a heating, constant-temperature and cooling area of the roller kiln is 15m, the heating speed of the heating area is 3 ℃/min, the temperature of the heat preservation area is set to be 760 ℃, so that the material passes through the constant-temperature area under the oxygen atmosphere, and the constant-temperature time is 3 hours;
11. and after the materials are sintered, obtaining a modified ternary cathode material product, bagging, vacuumizing and storing.
SEM and EDS characterization is performed on the modified ternary cathode material product prepared in example 1, and the results are shown in fig. 2 to 5 and table 1, where fig. 2 and fig. 3 are an SEM image and an SEM-EDX surface scanning image of the same part of the product, respectively, and fig. 3 specifically shows the distribution of rare earth elements on the surface of the modified ternary cathode material in fig. 2. It can be seen by overlapping fig. 2 and fig. 3 that the distribution of the rare earth elements on the surface of the modified ternary cathode material is very uniform. The characterization result shows that 50-60% of neodymium element enters the interior of the ternary material crystal lattice in the modified material with the neodymium element doping proportion of 1-3 wt%, so that cation mixed-emission and electron transmission of the ternary material are improved, and in addition, about 50% of neodymium element is coated on the surface of the ternary material, so that the effect of reducing side reactions between the anode material and the electrolyte can be achieved.
TABLE 1 elemental analysis
| Element(s) | wt％ | wt％Sigma | Atomic percent |
| C | 16.78 | 0.36 | 32.63 |
| O | 32.40 | 0.27 | 47.29 |
| Mn | 3.60 | 0.11 | 1.53 |
| Co | 5.50 | 0.17 | 2.18 |
| Ni | 40.77 | 0.33 | 16.22 |
| Nd | 0.95 | 0.17 | 0.15 |
| Total amount of | 100.00 | 100.00 |
Comparative example 1
With Nd (NO)3)3·6H2O is a rare earth coating agent, the modified ternary cathode material is prepared by a dry coating method, the coating method is controlled to be single variable, the ternary cathode material in the product is an NCM811 material, and the doping proportion of the rare earth elements is the same as that in the example 1. Experimental results show that the dry coating method cannot enable the rare earth elements to be uniformly coated on the surface of the ternary cathode material, and the rare earth elements fall off or even agglomerate in the subsequent pulping process of the cathode material, so that the coating is not uniform.
Comparative example 2
The modified ternary anode material coated by the aluminum oxide is prepared by taking an aluminum-containing material as a coating agent through a conventional method, the coating method is controlled to be a single variable, the ternary anode material in the product is an NCM811 material, and the doping proportion of the rare earth element is the same as that in the example 1.
Test example
The modified ternary positive electrode materials prepared in example 1 and comparative example 2 and the uncoated NCM811 material (referred to as comparative example 3) were used to prepare test cells, and the cycle performance was tested. The test results show that the cycle performance of the battery made of the neodymium-coated modified ternary cathode material (example 1) is close to that of the battery made of the aluminum oxide-coated modified ternary cathode material (comparative example 2). However, the cell made of the material of comparative example 2 was found to have a significantly higher dc internal resistance than the material of example 1 by internal resistance testing. In addition, referring to fig. 6, it can be seen from example 1 and comparative example 3 that the cycle performance of the battery cell made of the modified ternary cathode material coated with the rare earth element is significantly higher than that of the battery cell made of the uncoated ternary cathode material, and the reproducibility of the result is good.
In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.
Claims (10)
1. A method of preparing a modified ternary cathode material, comprising:
(1) mixing a rare earth coating agent with water to obtain a coating solution;
(2) carrying out wet coating treatment on the coating liquid and the ternary cathode material so as to form a coating layer on at least part of the surface of the ternary cathode material to obtain a coating mixed material;
(3) and sintering the coating mixed material to obtain the modified ternary cathode material.
2. The method of claim 1, wherein the rare earth capping agent comprises at least one selected from the group consisting of gadolinium salts, terbium salts, lanthanum salts, cerium salts, and neodymium salts.
3. The method according to claim 1, wherein the mass ratio of the rare earth cladding agent to the water is (2-4): (30-60).
4. The method of claim 1, wherein the ternary cathode material is a nickel-cobalt-manganese ternary cathode material or a nickel-cobalt-aluminum ternary cathode material.
5. The method according to claim 1, wherein the rare earth coating agent accounts for 0.5-2% mol of the total mass of the coating mixture.
6. The method according to claim 1, wherein the wet coating treatment comprises a first mixing treatment and a second mixing treatment which are sequentially performed, wherein the first mixing treatment is performed at a rotation speed of 20-40 r/min for 5-10 min, and the second mixing treatment is performed at a rotation speed of 50-80 r/min for 20-45 min.
7. The method of claim 1, wherein the sintering process comprises: and heating the coating material to 700-900 ℃ at a heating rate of 2-4 ℃/min in an oxidizing atmosphere, and preserving heat for 3-6 h.
8. The method of claim 1, further comprising, prior to step (3), drying the coating composition.
9. The method according to claim 8, wherein the drying treatment is performed at 120 to 180 ℃.
10. A modified ternary cathode material, characterized in that the modified ternary cathode material is prepared by the method of any one of claims 1 to 9.
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111725514A (en) * | 2020-06-30 | 2020-09-29 | 中南大学 | Modification method of high-nickel ternary cathode material of lithium ion battery |
| CN114226712A (en) * | 2021-12-14 | 2022-03-25 | 英特派铂业股份有限公司 | Efficient fusion coating process for silver powder surface |
| CN114715956A (en) * | 2022-04-29 | 2022-07-08 | 山东友邦科思茂新材料有限公司 | Modified porous nickel-rich cathode material and preparation method thereof |
| CN117239087A (en) * | 2023-09-25 | 2023-12-15 | 巴斯夫杉杉电池材料有限公司 | Modified ternary positive electrode material and preparation method thereof |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102931388A (en) * | 2012-11-23 | 2013-02-13 | 惠州亿纬锂能股份有限公司 | Rare earth oxide clad lithium titanate anode material, preparation method thereof and lithium ion battery |
| US20140377655A1 (en) * | 2013-06-24 | 2014-12-25 | Samsung Electronics Co., Ltd. | Composite cathode active material, method of preparing the composite cathode active material, and cathode and lithium battery each including the composite cathode active material |
| CN105576215A (en) * | 2016-03-02 | 2016-05-11 | 合肥国轩高科动力能源有限公司 | Surface modification method of anode material of lithium ion battery |
| CN108461737A (en) * | 2018-03-21 | 2018-08-28 | 苏州林奈新能源有限公司 | A kind of nickel cobalt aluminium ternary anode material for lithium-ion batteries, the Preparation method and use of cladding |
| US20180316005A1 (en) * | 2017-04-28 | 2018-11-01 | Samsung Electronics Co., Ltd. | Positive active material, positive electrode and lithium secondary battery containing the material, and method of preparing the material |
| CN109037633A (en) * | 2018-07-31 | 2018-12-18 | 湖南德景源科技有限公司 | A method of the modified nickelic positive electrode of production is heat-treated using rotary kiln |
| CN109599545A (en) * | 2018-12-04 | 2019-04-09 | 中国科学院青海盐湖研究所 | A kind of tertiary cathode material and preparation method thereof, lithium ion battery |
-
2019
- 2019-11-08 CN CN201911087623.6A patent/CN110854383A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102931388A (en) * | 2012-11-23 | 2013-02-13 | 惠州亿纬锂能股份有限公司 | Rare earth oxide clad lithium titanate anode material, preparation method thereof and lithium ion battery |
| US20140377655A1 (en) * | 2013-06-24 | 2014-12-25 | Samsung Electronics Co., Ltd. | Composite cathode active material, method of preparing the composite cathode active material, and cathode and lithium battery each including the composite cathode active material |
| CN105576215A (en) * | 2016-03-02 | 2016-05-11 | 合肥国轩高科动力能源有限公司 | Surface modification method of anode material of lithium ion battery |
| US20180316005A1 (en) * | 2017-04-28 | 2018-11-01 | Samsung Electronics Co., Ltd. | Positive active material, positive electrode and lithium secondary battery containing the material, and method of preparing the material |
| CN108461737A (en) * | 2018-03-21 | 2018-08-28 | 苏州林奈新能源有限公司 | A kind of nickel cobalt aluminium ternary anode material for lithium-ion batteries, the Preparation method and use of cladding |
| CN109037633A (en) * | 2018-07-31 | 2018-12-18 | 湖南德景源科技有限公司 | A method of the modified nickelic positive electrode of production is heat-treated using rotary kiln |
| CN109599545A (en) * | 2018-12-04 | 2019-04-09 | 中国科学院青海盐湖研究所 | A kind of tertiary cathode material and preparation method thereof, lithium ion battery |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111725514A (en) * | 2020-06-30 | 2020-09-29 | 中南大学 | Modification method of high-nickel ternary cathode material of lithium ion battery |
| CN114226712A (en) * | 2021-12-14 | 2022-03-25 | 英特派铂业股份有限公司 | Efficient fusion coating process for silver powder surface |
| CN114715956A (en) * | 2022-04-29 | 2022-07-08 | 山东友邦科思茂新材料有限公司 | Modified porous nickel-rich cathode material and preparation method thereof |
| CN114715956B (en) * | 2022-04-29 | 2023-09-12 | 山东友邦科思茂新材料有限公司 | Modified porous nickel-rich positive electrode material and preparation method thereof |
| CN117239087A (en) * | 2023-09-25 | 2023-12-15 | 巴斯夫杉杉电池材料有限公司 | Modified ternary positive electrode material and preparation method thereof |
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