CN114180637A - Cation disordered lithium-rich cathode material and preparation method thereof - Google Patents
Cation disordered lithium-rich cathode material and preparation method thereof Download PDFInfo
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- C01G45/125—Manganates or manganites with a manganese oxidation state of Mn(III), Mn(IV) or mixtures thereof of the type[MnO3]n-, e.g. Li2MnO3, Li2[MxMn1-xO3], (La,Sr)MnO3
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Abstract
The invention provides a cation disordered lithium-rich cathode material and a preparation method thereof, and relates to the technical field of lithium ion batteries2+xMyMnzO3Wherein M is a transition metal element, x is more than or equal to 0 and less than or equal to 0.5, z is more than or equal to 0.2 and less than or equal to 0.4, and x +3y +4z is 4. The cation disordered lithium-rich cathode material prepared by the invention contains high-valence manganese ions and transition metal ions, and is beneficial to the conversion of the material from a layered structure to a layered structure in the preparation processThe modified porous carbon material is changed into a three-dimensional disordered structure, the structural stability of the material is improved, the cycle performance is improved, a special lithium ion transmission channel is provided, the rapid transmission of lithium ions is carried out through a Yu-osmosis mechanism, the transmission efficiency is improved, the improvement of the specific capacity is facilitated, the synthesis process is simple, the production efficiency is high, the raw materials are cheap, and the process cost is low.
Description
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a cation disordered lithium-rich cathode material and a preparation method thereof.
Background
The electric energy is one of the most environment-friendly energy forms, has rich and various sources, and can effectively solve the problems of non-regeneration of the existing fossil fuel, environmental pollution and the like. Therefore, there is an increasing demand for lithium ion secondary batteries having high specific energy.
Common cathode materials used in modern lithium ion batteries include lithium cobaltate (LiCoO)2) Lithium nickelate (LiNiO)2) Lithium manganate (LiMnO)2、LiMn2O4) And lithium iron phosphate (LiFePO)4). Lithium cobaltate is the most widely used anode material at present, and the process is the most mature. However, lithium cobaltate has high synthesis cost, low safety performance, short battery life and low cycle number, so the specific capacity of the lithium cobaltate is generally limited to 125mAh/g in practical use. Compared with lithium cobaltate, the synthesis cost of the lithium nickelate is greatly reduced, the raw material source is rich, and the specific capacity is far higher than that of the lithium cobaltate and reaches 200-220 mAh/g. However, the synthesis of pure-phase lithium nickelate is difficult and is often doped with Ni2+，Ni2+With Li+Mix-discharging, which hinders the desorption of lithium ions and reduces the battery capacity. The specific capacity of the layered lithium manganate with the same structure as that of lithium cobaltate is much higher than that of the lithium cobaltate by 285mAh/g, but the layered lithium manganate also has the problem of difficult pure-phase synthesis because Mn3+ is easy to be converted into Mn through disproportionation reaction2+And Mn4+This also leads to a reduction in battery capacity and a reduction in stability. The spinel type lithium manganate has a theoretical capacity of 148mAh/g, is simple in synthesis compared with a layered structure, but is easy to generate Jahn-Teller effect in the cyclic charge-discharge process to cause lattice distortion, so that the capacity of a battery is reduced, and the cyclic performance and stability are reduced。
Disclosure of Invention
The invention solves at least one problem of difficult preparation, short service life, poor cycle stability and low cost of the anode material of the lithium ion battery in the prior art.
In order to solve the problems, the invention provides a cation disordered lithium-rich cathode material which has a cation disordered rock salt structure, and the molecular formula of the cation disordered lithium-rich cathode material is Li2+xMyMnzO3Wherein M is a transition metal element, x is more than or equal to 0 and less than or equal to 0.5, z is more than or equal to 0.2 and less than or equal to 0.4, and x +3y +4z is 4.
Preferably, the transition metal element includes one of Co, Ni, Cr, V, Ti, Nb, Al, or Fe.
Compared with the prior art, the cation disordered lithium-rich cathode material has the advantages that on one hand, the cation disordered lithium-rich cathode material based on the high-valence manganese-based system has a special lithium ion transmission channel, the lithium ion transmission speed is high, the super-lithium content is high, more lithium ions can be provided in the charging and discharging process, and the specific capacity and the energy density are high. On the other hand, compared with the traditional layered cathode material, the disordered cathode material of the high-valence manganese-based system adopted by the invention has a more stable disordered cation framework and a more stable crystal structure, so that the disordered cathode material has better cycle performance and cycle stability.
In order to solve the problems, the invention also provides a preparation method of the cation disordered lithium-rich cathode material, which comprises the following steps:
step S1, LiNO3、MnO2And drying the oxide of M after ball milling to obtain precursor powder, wherein M is a transition metal element;
step S2, heat-treating the precursor powder;
and step S3, performing ball milling on the precursor powder after heat treatment again, and drying to obtain the cation disordered lithium-rich cathode material.
Preferably, in step S1, the ball milling process includes: in a ball milling tank, according to the proportion of 1: and (2) adding ball grinding balls according to the ball-to-material ratio of (2-4), adding a first grinding aid, sealing the ball grinding tank, and putting the ball grinding tank into a mixer to perform ball grinding for 11-12 hours at the speed of 80-100 r/min.
Preferably, in step S1, the drying process includes: drying at 55-65 deg.C for 5-7 hr.
Preferably, the heat treatment process in step S2 includes: heating the mixture in a tubular furnace from room temperature to 650 plus 750 ℃ at the speed of 2-4 ℃/min, preserving heat for 1.5-2.5 hours, heating the mixture to 800 plus 1200 ℃ at the speed of 2-4 ℃/min, preserving heat for 8-18 hours, and cooling along with the furnace after the heat preservation is finished.
Preferably, the heat treatment process further comprises: and introducing a protective atmosphere into the tubular furnace.
Preferably, in step S3, the process of ball milling again includes: in a ball milling tank, according to the proportion of 1: and (2) adding ball grinding balls according to the ball-to-material ratio of (2-4), adding a second grinding aid, sealing the ball grinding tank, and then putting the ball grinding tank into a mixer to perform ball grinding for 12-30 hours at the speed of 300-.
Preferably, in step S3, the drying process includes: drying at 75-95 deg.C for 11-13 hr.
Preferably, the first grinding aid and/or the second grinding aid comprises one of isopropyl alcohol, ethylene glycol, or propylene glycol.
Compared with the prior art, the preparation method of the cation disordered lithium-rich cathode material has the advantages of low process requirement, low equipment cost, low cost of adopted raw materials, no generation of byproducts harmful to the environment in the production process, high safety and suitability for large-scale industrial production. The preparation method of the cation disordered lithium-rich cathode material has the same advantages as the cation disordered lithium-rich cathode material compared with other advantages in the prior art, and is not repeated herein.
Drawings
FIG. 1 is a schematic structural diagram of a cation disordered lithium-rich cathode material in an embodiment of the invention;
FIG. 2 is a flow chart of a method for preparing a cation disordered lithium-rich cathode material in an embodiment of the invention;
FIG. 3 is a XRD test result chart of the cation disordered lithium-rich cathode material in the embodiment of the invention;
FIG. 4 is a SEM test result chart of the cation disordered lithium-rich cathode material in the embodiment of the invention;
FIG. 5 is a discharge specific capacity cycling performance diagram of the cation disordered lithium-rich cathode material at a current density of 20mA/g in the embodiment of the invention.
Detailed Description
The technical solutions in the embodiments of the present application will be described in detail and clearly with reference to the accompanying drawings.
In the description of the embodiments herein, the description of the term "some embodiments" means 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. Throughout this specification, the schematic representations of the terms used above do not necessarily refer to the same implementation 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.
As shown in fig. 1, an embodiment of the present invention provides a cation-disordered lithium-rich cathode material, which has a cation-disordered rock salt structure, and a molecular formula of the cation-disordered lithium-rich cathode material is Li2+xMyMnzO3Wherein M is a transition metal element, x is more than or equal to 0 and less than or equal to 0.5, z is more than or equal to 0.2 and less than or equal to 0.4, and x +3y +4z is 4.
It should be noted that lithium ion diffusion in the cation disordered lithium-rich cathode material depends on the transition of double vacancy between octahedrons, tetrahedral sites exist between the octahedrons, so that the migration of lithium ions is performed in an octahedron-tetrahedron-octahedron mode, static electricity in the migration process can influence the migration of lithium ions, lithium ions in the tetrahedral sites are in an excited state, and therefore, the ionic valence state near the tetrahedral sites influences the migration rate.
In this embodiment, the anode material Li is a disordered lithium-rich anode material2+xMyMnzO3Is based on Li2MnO3Designed with Li content of 2+ x, compared toIn Li2MnO3When the addition amount of the excessive lithium is x, x/2 is the amount of the excessive lithium, and a percolation effect can be formed when 2-25% of the excessive lithium is contained, but a smooth voltage curve cannot be generated in the charging and discharging process when the excessive lithium content exceeds 25%, and the phenomenon of sudden voltage attenuation can occur after certain times of circulation. Thus, x/2 needs to be not greater than 0.25, then 0. ltoreq. x.ltoreq.0.5. The positive electrode is made to form a cation disordered structure, a 0-TM channel is formed around the tetrahedral lattice points under the state of lithium enrichment, and a percolation network is finally formed, and the diffusion energy barrier of the percolation network is obviously lower than that of a conventional positive electrode material, so that the percolation network has higher specific discharge capacity and energy density.
It should be further noted that the oxidation valence and ionic radius of the transition metal element of the cation disordered lithium-rich cathode material directly affect the electrochemical performance of the cathode material. The problem of oxygen loss in disordered positive electrode materials during charging and discharging is mainly due to the reduced stability of the crystal structure after the disordered state of cations is formed. And Mn in the positive electrode of the battery4+Basically has no electrochemical activity and cannot be oxidized into 5+, so the Mn with lower electrochemical activity is adopted in the embodiment of the invention4+Supporting the crystal structure and improving the structural stability. As can be seen from the figure, Li+The radius is small, and the positive ion disorder lithium-rich positive electrode is mainly composed of Mn4+Supporting the crystal structure and improving the stability of the crystal. On the one hand, the Mn can be known through theoretical calculation of the crystal structure4+At least 0.2, or otherwise converted to a spinel structure at high temperatures. On the other hand, Mn in the crystal structure4+Electrostatic effect on Li as large-size transition metal ion+The long-range diffusion ability of Mn is greatly influenced when Mn is added4+The content of (2) exceeding 0.4 remarkably lowers Li+Long-range diffusion capability. Therefore, z is more than or equal to 0.2 and less than or equal to 0.4.
And because of the crystal structure of the cation disordered lithium-rich cathode material and LiMO2The layered structure has similarity, and thus can be doped with trivalent active elements such as Fe, Co, Ni, Al, Cr, V, Ti and Nb to provide charge compensation, whereby, in some preferred embodiments, the transition metal elements include Co, Ni, Cr, V, Ti, Nb, Al or FeThe combination of the Mn4+ and the structural support effect can improve the cycle performance of the cathode material.
In this example, x +3y +4z is 4, which satisfies the requirement of the valence of the molecule.
Therefore, compared with the prior art, the positive ion disordered lithium-rich positive electrode material provided by the embodiment of the invention has the advantages that on one hand, the positive ion disordered lithium-rich positive electrode material based on the high-valence manganese-based system contains high-valence manganese ions and transition metal ions, is beneficial to converting a layered structure into a three-dimensional disordered structure in the preparation process, has a special lithium ion transmission channel, is high in lithium ion transmission speed and ultra-high in lithium content, can provide more lithium ions in the charging and discharging process, and has high specific capacity and energy density. On the other hand, compared with the traditional layered cathode material, the disordered cathode material of the high-valence manganese-based system adopted in the embodiment of the invention has a more stable disordered cation framework and a more stable crystal structure, so that the disordered cathode material has better cycle performance and cycle stability.
As shown in fig. 2, another embodiment of the present invention further provides a method for preparing a cation disordered lithium-rich cathode material, comprising the following steps:
step S1, LiNO3、MnO2And drying the oxide of M after ball milling to obtain precursor powder, wherein M is a transition metal element;
step S2, heat-treating the precursor powder;
and step S3, performing ball milling on the precursor powder after heat treatment again, and drying to obtain the cation disordered lithium-rich cathode material.
In some preferred embodiments, the oxide of M comprises Cr2O3、V2O3、Nb2O3、Co2O3、Ti2O3Or Ni2O3To provide charge compensation. And the material is easy to obtain and the cost is low.
In some embodiments, in step S1, the ball milling process includes: in a ball milling tank, according to the proportion of 1: and (2) adding ball grinding balls according to the ball-to-material ratio of (2-4), adding a first grinding aid, sealing the ball grinding tank, and putting the ball grinding tank into a mixer to perform ball grinding for 11-12 hours at the speed of 80-100 r/min. Therefore, all raw materials are uniformly mixed, the first grinding aid is added, particle agglomeration can be prevented, the material fluidity is improved, the ball milling efficiency is improved, and the grinding time is shortened.
In some embodiments, in step S1, the drying process includes: drying at 55-65 deg.C for 5-7 hr. Thereby completely volatilizing the first grinding aid.
In some embodiments, the heat treatment in step S2 includes: heating the mixture in a tubular furnace from room temperature to 650 plus 750 ℃ at the speed of 2-4 ℃/min, preserving heat for 1.5-2.5 hours, heating the mixture to 800 plus 1200 ℃ at the speed of 2-4 ℃/min, preserving heat for 8-18 hours, and cooling along with the furnace after the heat preservation is finished. Thereby, the heat treatment effect is better.
In some embodiments, the heat treatment process further comprises: and introducing a protective atmosphere into the tubular furnace. Therefore, oxygen, moisture and the like in the air are prevented from participating in the reaction, and the purity of the material is prevented from being influenced.
In some preferred embodiments, the protective atmosphere is argon, and the materials are readily available.
In some embodiments, in step S3, the re-ball milling process includes: in a ball milling tank, according to the proportion of 1: and (2) adding ball grinding balls according to the ball-to-material ratio of (2-4), adding a second grinding aid, sealing the ball grinding tank, and then putting the ball grinding tank into a mixer to perform ball grinding for 12-30 hours at the speed of 300-. Therefore, the precursor powder after heat treatment is uniformly mixed, and the second grinding aid is added to prevent particle agglomeration and improve material fluidity, so that the ball milling efficiency is improved, and the grinding time is shortened.
In some embodiments, in step S3, the drying process includes: drying at 75-95 deg.C for 11-13 hr. Thereby completely evaporating the second grinding aid.
In some preferred embodiments, the first grinding aid and/or the second grinding aid comprises one of isopropyl alcohol, ethylene glycol, or propylene glycol. Thus, the materials are easy to obtain, and the addition of the first grinding aid and/or the second grinding aid can prevent particle agglomeration and improve material fluidity, thereby improving the ball milling efficiency and shortening the grinding time.
Therefore, the preparation method adopted by the embodiment has the advantages of low process requirements, low equipment cost, low cost of adopted raw materials, no generation of byproducts harmful to the environment in the production process, high safety and suitability for large-scale industrial production. In addition, the preparation method of the positive electrode material with disordered lithium-rich cations described in this embodiment has the same advantages as the positive electrode material with disordered lithium-rich cations compared with the prior art, and is not described herein again.
Example 1
The embodiment of the invention provides a preparation method of a cation disordered lithium-rich cathode material, which comprises the following steps:
(1) reacting LiNO with a catalyst3、MnO2And Ti2O3Weighing according to stoichiometric ratio, preliminarily mixing the weighed raw material powder, adding into a ball milling tank, and mixing according to the proportion of 1: 3, adding ball grinding balls according to the ball-to-material ratio, finally adding a proper amount of isopropanol, sealing a ball grinding tank, putting the ball grinding tank into a mixer, carrying out ball grinding for 12 hours at the speed of 90r/min, taking the uniformly mixed slurry out of a constant-temperature table type drying box, drying for 6 hours at the temperature of 60 ℃ until the isopropanol is completely volatilized, and collecting the dried precursor powder.
(2) Sending the precursor powder into a tube furnace, introducing argon, heating from room temperature to 700 ℃ at the speed of 3 ℃/min, preserving heat for 2 hours, heating to 1000 ℃ at the speed of 3 ℃/min, preserving heat for 16 hours, and cooling along with the furnace after the heat preservation is finished.
(3) And (3) taking out the mother powder after cooling, adding the mother powder into a ball milling tank, and mixing the mother powder and the ball milling tank according to the proportion of 1: 3, adding ball grinding balls according to the ball-to-material ratio, adding a proper amount of isopropanol, sealing a ball grinding tank, and carrying out ball grinding for 24 hours at the speed of 480 r/min. And (3) after the ball milling is finished, taking out the slurry, transferring the slurry into a vacuum drying box, and drying the slurry in vacuum for 12 hours at the temperature of 80 ℃ to obtain the cation disordered lithium-rich cathode material.
As shown in FIG. 3, FIG. 3 shows Li, a cation-disordered lithium-rich cathode material prepared in this example2.4Ti0.4Mn0.5O3The results of XRD measurement in the above-mentioned sample are shown in the figure, from which it is understood that the sample was prepared by the present exampleThe prepared positive electrode material has characteristic peaks of (111), (002), (022), (113) and (222) at 36.5 degrees, 42.9 degrees, 63.4 degrees, 76.6 degrees and 80.4 degrees respectively, which indicates that the positive electrode material is a cubic crystal system, has Fm-3m space group and has a cation disordered rock salt structure. And no other characteristic peak appears in the XRD result diagram, which indicates that the prepared sample is Li2.4Ti0.4Mn0.5O3Pure phase.
As shown in fig. 4, fig. 4 is a SEM test result of the positive electrode material with disordered positive ions prepared in this example, and it can be seen from the figure that the particle size of the positive electrode material after ball milling is about 1-2 μm, the edge angle of the particle is obvious, and a certain particle agglomeration phenomenon occurs.
As shown in fig. 5, fig. 5 is a graph of specific discharge capacity cycling performance of the cation disordered lithium-rich cathode material prepared in the embodiment at a current density of 20 mA/g. The figure shows that the first discharge specific capacity is 307.29mAh/g, and the specific capacity is 241.36mAh/g after the cycle is carried out for 50 times.
Therefore, the cation disordered lithium-rich cathode material prepared by the embodiment contains high-valence manganese ions and transition metal ions, the layered structure of the material is favorably changed into a three-dimensional disordered structure in the preparation process, the structural stability of the material is improved, the cycle performance is improved, meanwhile, a special lithium ion transmission channel is provided, the lithium ions are rapidly transmitted through a Yu-infiltration mechanism, the transmission efficiency is improved, and the specific capacity is favorably improved.
Example 2
The embodiment of the invention provides a preparation method of a cation disordered lithium-rich cathode material, which comprises the following steps:
(1) reacting LiNO with a catalyst3、MnO2And Cr2O3Weighing according to stoichiometric ratio, preliminarily mixing the weighed raw material powder, adding into a ball milling tank, and mixing according to the proportion of 1: 2, adding ball grinding balls, finally adding a proper amount of isopropanol, sealing a ball grinding tank, putting the ball grinding tank into a mixer, and ball-grinding for 11 hours at the speed of 80r/min, and after the ball grinding is finished, adding the mixture into the mixerAnd taking the uniformly mixed slurry out of a constant-temperature desk type drying oven, drying for 6 hours at 65 ℃ until isopropanol is completely volatilized, and collecting dried precursor powder.
(2) Sending the precursor powder into a tube furnace, introducing argon, heating from room temperature to 650 ℃ at the speed of 2 ℃/min, preserving heat for 1.5 hours, heating to 800 ℃ at the speed of 2 ℃/min, preserving heat for 10 hours, and cooling along with the furnace after the heat preservation is finished.
(3) And (3) taking out the mother powder after cooling, adding the mother powder into a ball milling tank, and mixing the mother powder and the ball milling tank according to the proportion of 1: 2, adding ball grinding balls according to the ball-to-material ratio, adding a proper amount of isopropanol, sealing a ball grinding tank, and carrying out ball grinding for 30 hours at the speed of 300 r/min. And (3) after the ball milling is finished, taking out the slurry, transferring the slurry into a vacuum drying box, and drying for 13 hours in vacuum at the temperature of 75 ℃ to obtain the cation disordered lithium-rich cathode material.
Example 3
The embodiment of the invention provides a preparation method of a cation disordered lithium-rich cathode material, which comprises the following steps:
(1) reacting LiNO with a catalyst3、MnO2And V2O3Weighing according to stoichiometric ratio, preliminarily mixing the weighed raw material powder, adding into a ball milling tank, and mixing according to the proportion of 1: 4, adding ball grinding balls according to the ball-to-material ratio, finally adding a proper amount of isopropanol, sealing a ball grinding tank, putting the ball grinding tank into a mixer, carrying out ball grinding for 12 hours at the speed of 100r/min, taking the uniformly mixed slurry out of a constant-temperature table type drying box, drying for 7 hours at the temperature of 55 ℃ until the isopropanol is completely volatilized, and collecting the dried precursor powder.
(2) Sending the precursor powder into a tube furnace, introducing argon, heating from room temperature to 750 ℃ at the speed of 4 ℃/min, preserving heat for 2.5 hours, heating to 1200 ℃ at the speed of 4 ℃/min, preserving heat for 18 hours, and cooling along with the furnace after the heat preservation is finished.
(3) And (3) taking out the mother powder after cooling, adding the mother powder into a ball milling tank, and mixing the mother powder and the ball milling tank according to the proportion of 1: 4, adding ball grinding balls according to the ball-to-material ratio, adding a proper amount of isopropanol, sealing a ball grinding tank, and carrying out ball grinding for 12 hours at the speed of 500 r/min. And (3) after the ball milling is finished, taking out the slurry, transferring the slurry into a vacuum drying box, and drying for 11 hours in vacuum at the temperature of 95 ℃ to obtain the cation disordered lithium-rich cathode material.
Although the present disclosure has been described above, the scope of the present disclosure is not limited thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present disclosure, and these changes and modifications are intended to be within the scope of the present disclosure.
Claims (10)
1. The positive electrode material is characterized by having a positive disordered rock salt structure, and the molecular formula of the positive electrode material is Li2+xMyMnzO3Wherein M is a transition metal element, x is more than or equal to 0 and less than or equal to 0.5, z is more than or equal to 0.2 and less than or equal to 0.4, and x +3y +4z is 4.
2. The cationic disordered lithium-rich cathode material of claim 1, wherein the transition metal element comprises one of Co, Ni, Cr, V, Ti, Nb, Al, or Fe.
3. A method for preparing the cation disordered lithium-rich cathode material according to claim 1 or 2, characterized by comprising the following steps:
step S1, LiNO3、MnO2And drying the oxide of M after ball milling to obtain precursor powder, wherein M is a transition metal element;
step S2, heat-treating the precursor powder;
and step S3, performing ball milling on the precursor powder after heat treatment again, and drying to obtain the cation disordered lithium-rich cathode material.
4. The method for preparing the cation disordered lithium-rich cathode material of claim 3, wherein in the step S1, the ball milling process comprises the following steps: in a ball milling tank, according to the proportion of 1: and (2) adding ball grinding balls according to the ball-to-material ratio of (2-4), adding a first grinding aid, sealing the ball grinding tank, and putting the ball grinding tank into a mixer to perform ball grinding for 11-12 hours at the speed of 80-100 r/min.
5. The method for preparing the cation disordered lithium-rich cathode material according to claim 3, wherein in the step S1, the drying process comprises the following steps: drying at 55-65 deg.C for 5-7 hr.
6. The method for preparing a cation disordered lithium-rich cathode material according to claim 3, wherein the heat treatment process in the step S2 comprises the following steps: heating the mixture in a tubular furnace from room temperature to 650 plus 750 ℃ at the speed of 2-4 ℃/min, preserving heat for 1.5-2.5 hours, heating the mixture to 800 plus 1200 ℃ at the speed of 2-4 ℃/min, preserving heat for 8-18 hours, and cooling along with the furnace after the heat preservation is finished.
7. The method for preparing the cation disordered lithium-rich cathode material according to claim 6, wherein the heat treatment process further comprises the following steps: and introducing a protective atmosphere into the tubular furnace.
8. The method for preparing the cation disordered lithium-rich cathode material according to claim 3, wherein in the step S3, the process of ball milling again comprises the following steps: in a ball milling tank, according to the proportion of 1: and (2) adding ball grinding balls according to the ball-to-material ratio of (2-4), adding a second grinding aid, sealing the ball grinding tank, and then putting the ball grinding tank into a mixer to perform ball grinding for 12-30 hours at the speed of 300-.
9. The method for preparing the cation disordered lithium-rich cathode material according to claim 3, wherein in the step S3, the drying process comprises the following steps: drying at 75-95 deg.C for 11-13 hr.
10. The method for preparing the cation disordered lithium-rich cathode material according to claim 4 or 8, wherein the first grinding aid or the second grinding aid comprises one of isopropanol, ethylene glycol or propylene glycol.
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