CN113871588A - Lithium battery core-shell cathode material, lithium battery containing lithium battery core-shell cathode material and preparation method of lithium battery - Google Patents
Lithium battery core-shell cathode material, lithium battery containing lithium battery core-shell cathode material and preparation method of lithium battery Download PDFInfo
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Abstract
The invention discloses a lithium battery core-shell cathode material, a lithium battery containing the lithium battery core-shell cathode material and a preparation method thereof. The core of the anode material is a lithium ion battery anode material, and the shell layer is a composite conductive network consisting of a solid electrolyte and (or) conductive carbon and lithium salt. The preparation method is characterized in that a stable and uniform coating layer is formed on the surface of the anode material by utilizing the low-temperature solubility of lithium salt and a mode of solvent evaporation, recrystallization and solidification after the lithium salt solution is fused with the solid electrolyte by ball milling. The preparation method has the advantages of low temperature and environmental protection, and realizes the reduction of interface resistance and the weakening of side reactions by stably forming a high-ion and electron-conductive uniform coating layer on the surface of the lithium battery anode material on the premise of ensuring low carbon and low energy consumption, thereby finally greatly improving the stability and the electrochemical performance of the anode material.
Description
Technical Field
The invention belongs to the field of lithium battery materials, and particularly relates to a high-performance core-shell structure cathode material, a lithium battery containing a lithium battery core-shell cathode material and a preparation method thereof.
Background
In recent years, energy consumption and environmental pollution become problems to be solved in urgent need in all countries of the world, and development of an environment-friendly renewable energy system becomes a focus of attention in all countries. The lithium ion battery is an important discovery of an energy storage system for overcoming global energy requirements and environmental problems, and meanwhile, along with the continuous improvement of market requirements on electrical equipment, the demands on the lithium ion battery with high specific energy density, high working voltage, long cycle life, high safety and no memory effect are more urgent at home and abroad.
The anode material is a key material of the lithium ion battery, has high differentiation degree and high cost-to-occupation ratio, and is very important to performance. Conventional lithium ion batteries, such as layered ternary nickel cobalt manganese lithium batteries, lithium cobaltate, lithium nickel manganese oxide and lithium iron phosphate, have short plates in voltage, energy density, service life and the like, and cannot meet market demands. High voltage and high energy density lithium ion batteries are the focus of research today.
However, the above-mentioned lithium ion batteries have many problems in application, and especially the attenuation of battery energy in a liquid electrolyte system becomes a major obstacle to the development of the battery. And the occurrence of side reaction of the electrode material and the electrolyte interface, the structural collapse caused by the microcracks is the main factor causing the rapid reduction of the battery capacity and the low coulombic efficiency. At present, modification is mainly carried out by means of surface coating of a positive electrode material, doping of a conductive material, doping of high-valence cations and nano-crystallization of size-reduced particles. The carbon-coated composite nano positive electrode material is an effective method for relieving capacity attenuation, but the modification method has a complex preparation process and usually needs higher temperature to synthesize (usually over 400 ℃), so that the environment is greatly influenced, and lithium ions are lost.
Disclosure of Invention
Aiming at the technical problems, the invention aims to provide a method for preparing a high-performance core-shell cathode material at a low temperature, which is simple in process, easy to operate and strong in repeatability, and a cathode material and a lithium battery prepared based on the preparation method. The preparation method provided by the invention can ensure environmental protection and low energy consumption, and the prepared cathode material has high electron and ion conductivity, small interface resistance, less side reaction, good cycle performance, excellent rate performance and excellent electrochemical performance.
The solid-state battery electrolyte with higher ionic conductivity is used as a main component and coated on the surface of the material, so that the diffusion efficiency of lithium ions can be improved; the conductive carbon has an amorphous porous structure and has the characteristic of higher electronic conductivity, so that the conductivity of the material is improved. The coating layer can reduce the contact between the anode material and electrolyte, and improve the conductivity and electrochemical performance of the anode material. Meanwhile, the lithium salt has higher ionic conductivity, reduces the interface resistance among particles, stabilizes a coating layer and further improves the structural stability and the conductivity of the material.
According to the invention, by utilizing the low-temperature solubility of lithium salt, a stable and uniform coating layer is formed on the surface of the anode material in a manner of solvent evaporation, recrystallization and solidification after the lithium salt solution is fused with the solid electrolyte by ball milling.
In order to achieve the above purpose, the invention adopts the following scheme:
the first aspect of the invention provides a preparation method of a lithium battery core-shell cathode material, which comprises the following steps:
s1, dissolving lithium salt and a lithium battery positive electrode material matrix in a solvent, and uniformly mixing to obtain a lithium salt-coated ternary solution; (ii) a
S2, ball-milling solid electrolyte and/or conductive carbon powder into superfine powder;
the solid electrolyte comprises Li1+pAlpGe2-p(PO4)3、Li3qLa2/3-qTiO3、LiZr2-rTir(PO4)3、Li1+ mAlmTi2-m(PO4)3、Li7-2n-jAnLa3Zr2-jXjO12、Li7-2n-2jAnLa3Zr2-jZjO12、Li3S4、Li4-tM1-tNtS4、Li2S-P2S5、Li2S-SiS2、Li2S-B2S3Wherein M is Ge, Si, N is P, A1, Zn, 0 < p < 2, 0 < q < 2/3, 0 < r < 2, 0 < M < 2, 0 < t < 1, 0 < N < 3, 0 < j < 2, wherein A is Ge or Al, X is Nb or Ta, Z is Te or W; the lithium salt includes LiI, LiBr, LiCl, LiF, Li3PO4、LiTFSI、LiPF6、LiBF4、LiClO4、LiCF3SO3、LiN(CF3SO2)2、LiBOB、Li2SiO4One or more of;
preferably, the solid electrolyte comprises Li1+mAlmTi2-m(PO4)3(LATP)、Li7-2n-jAnLa3Zr2-jXjO12(LLZTO)。
S3, adding the powder obtained in the step S2 into a lithium salt-coated ternary solution, and stirring and ball-milling to obtain a lithium salt-based solid electrolyte and/or conductive carbon co-coated product;
s4, calcining the co-coated product obtained in the step S3 in an oxygen or inert gas atmosphere, and cooling the sintered product to room temperature after sintering is completed to obtain a finished product with a stable structure, wherein the surface of each particle is bonded.
Further, in the step S1, the lithium battery positive electrode material substrateComprises the following steps: ternary Li1+zNixCoyD1-x-y-sEsO2Nickel manganese spinel LiNi0.5Mn1.5O4Lithium cobaltate Li1+zCo1-sEsO2Rich in lithium manganese tLi2MnO3·(1-t)Li1+zNixCoyMn1-x-y- sEsO2Lithium iron manganese phosphate-based Li1+zFexMn1-x-sEsPO4Lithium manganate Li1+zMn2-sEsO4Lithium iron phosphate Li1+zFe1-sEsPO4Wherein 0 is<x<1，0<y<1，0≤s<0.1，0≤z<0.1，0<x+y+s<1，0<t<1, D is Mn or Al, E is one of Ti, Zr, Nb, La, V and Mg. The particle size of the powder of the lithium battery anode material matrix after ball milling is 0.4-20 μm.
Further, in step S1, the solvent is one of water, N-methylpyrrolidone, Ethylene Carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), Ethyl Methyl Carbonate (EMC), Methyl Acetate (MA), Ethyl Acetate (EA), methanol, ethanol, ethylene glycol, amyl alcohol, diethyl ether, acetonitrile, acetone, pyridine, tetrahydrofuran, dimethylformamide, N-methylformamide, and a tetrahydrofuran solution of lithium borohydride.
Furthermore, the mass ratio of the lithium battery anode material matrix to the lithium salt to the solid electrolyte to the conductive carbon is 1:0.002-0.08:0.02-0.08: 0.002-0.8. Preferably, the mass ratio of the matrix of the lithium battery positive electrode material, the lithium salt, the solid electrolyte and/or the conductive carbon is 1: 0.005:0.05:0.05.
Further, in the step S2, the conductive carbon is Super-P, and the particle size is 20-100 nm.
Further, in the step S3, ball milling is performed until the solvent in the mixed slurry is completely volatilized, and the slurry is in a powder shape.
Further, in the step S3, the ball milling rotation speed is 100-.
Further, in the step S4, the calcination temperature is 100-350 ℃.
The mechanism analysis of the core-shell structure formed by the invention is as follows: the preparation method provided by the invention combines the adhesion effect of the low-temperature adhesive lithium salt, the fusion effect of the mechanical force of ball milling and the low-temperature sintering molding, and the solid electrolyte material and/or the conductive carbon composite conductive network are tightly coated on the surface of the anode material under the synergistic effect of the three.
The invention provides a lithium battery core-shell cathode material prepared by the method of the first aspect, wherein the core of the cathode material is a lithium battery cathode material, and the shell layer is a composite conductive network consisting of solid electrolyte, lithium salt and/or conductive carbon.
The third aspect of the invention provides a liquid or all-solid lithium battery prepared by using the lithium battery core-shell cathode material described in the second aspect.
The invention has the beneficial effects that:
(1) the preparation process adopts a low-temperature environment-friendly treatment mode, so that the problems of energy loss and environmental pollution caused by high-temperature sintering are thoroughly solved, and the problem of lithium volatilization in the high-temperature sintering is reduced by low-temperature treatment.
(2) The prepared anode material has higher electronic and ionic conductivity and good coating property, can be compared with an anode coating layer sintered at high temperature, can well reduce the contact between the electrode material and electrolyte, and has excellent electrochemical performance.
(3) The raw materials are low in price and easy to obtain, pollution-free, simple in preparation process, easy to operate and high in repeatability.
(4) The conductive carbon is used for increasing the electronic conductivity, the problem of poor self-abhorrent conductivity of the material can be improved, and the coating layer is favorable for improving the problem of microcracks in the charging and discharging process.
Drawings
FIG. 1 is an SEM photograph of a sample prepared in example 1 of the present invention.
FIG. 2 is a TEM image of a sample prepared in example 1 of the present invention.
FIG. 3 is an XRD pattern of samples prepared according to examples of the present invention and comparative examples;
FIG. 4 is a first charge and discharge curve of samples prepared according to examples of the present invention and comparative examples; wherein a is comparative example 1, b is example 1, C, d is the same series as example 1, C is LNMCO-5% LATP @ C, and d is LNMCO-7% LATP @ C.
Detailed Description
The invention is further illustrated below by means of a series of examples in order to better illustrate the content of the invention, which is not at all restricted thereto.
The matrix of the positive electrode material for lithium battery usable as the core in the present embodiment includes ternary Li1+zNixCoyD1-x-y-sEsO2Nickel manganese spinel LiNi0.5Mn1.5O4Lithium cobaltate Li1+zCo1-sEsO2Rich in lithium manganese tLi2MnO3·(1-t)Li1+ zNixCoyMn1-x-y-sEsO2Lithium iron manganese phosphate-based Li1+zFexMn1-x-sEsPO4Lithium manganate Li1+zMn2-sEsO4Lithium iron phosphate Li1+ zFe1-sEsPO4Wherein 0 is<x<1，0<y<1，0≤s<0.1，0≤z<0.1，0<x+y+s<1，0<t<1, D is Mn or Al, E is one of Ti, Zr, Nb, La, V and Mg. The Co-coated cathode material prepared in the examples is abbreviated as LM-LATP @ C (LM represents a coated active substance, M is one or more of Ni, Co and Mn, L is Li, and LATP represents Li1.3Al0.3Ti1.7(PO4)3The LATP @ C is a coating layer, the modified active material is in front of the transverse line, and the number in front of the LATP is the mass ratio of the LATP to the positive electrode material of the lithium battery.
Example 1
The method for preparing the cathode material and the lithium battery comprises the following steps:
(1) lithium iodide and a ternary material LiNi1/3Co1/3Mn1/3O2According to the mass ratio of 0.0025:1 is dissolved in ethanol phase, and is magnetically stirred for 1 hour at 25 ℃ to obtain uniform lithium iodide coated ternary solution.
(2) The mass ratio of LATP to conductive carbon Super-P is 1:1, placing the mixture in a ball milling tank, and ball milling the mixture for 2 hours by a ball mill at the speed of 100rpm/min under the protection of high-purity argon (99.999%) to obtain uniformly mixed powder.
(3) Adding the mixed powder obtained in the step (2) into a ternary solution, and mixing the mixed powder with a ternary material (LiNi)1/3Co1/ 3Mn1/3O2) The mass ratio is 0.05: 1, magnetically stirring uniformly, then carrying out ball milling again, wherein the ball milling speed is 240rpm/min, the duration time is 2h, and mechanically milling to obtain a product coated by both LATP and conductive carbon.
(4) And (4) putting the product obtained in the step (3) into a blast oven, heating to 80 ℃ in an oxygen atmosphere, staying for 30min, and then heating to 250 ℃ for 30min to prepare the lithium ion battery anode material coated by the LATP based on lithium iodide and the conductive carbon.
Example 2
The method for preparing the cathode material comprises the following steps:
(1) mixing lithium bromide with a ternary material LiNi1/3Co1/3Mn1/3O2According to the mass ratio of 0.005: 1 is dissolved in ethanol phase, and is magnetically stirred for 1 hour at 25 ℃ to obtain uniform lithium bromide coated ternary solution.
(2) The mass ratio of LATP to conductive carbon Super-P is 1:1, placing the mixture in a ball milling tank, and ball milling the mixture for 2 hours by a ball mill at the speed of 100rpm/min under the protection of high-purity argon (99.999%) to obtain uniformly mixed powder.
(3) Adding the mixed powder obtained in the step (2) into a ternary solution, and mixing the mixed powder with a ternary material (LiNi)1/3Co1/ 3Mn1/3O2) The mass ratio is 0.1: 1, magnetically stirring uniformly, then carrying out ball milling again, wherein the ball milling speed is 240rpm/min, the duration time is 2h, and mechanically milling to obtain a product coated by both LATP and conductive carbon.
(4) And (4) putting the product obtained in the step (3) into a blast oven, heating to 80 ℃ in an oxygen atmosphere, staying for 30min, heating to 250 ℃ and continuing for 30min to prepare the lithium ion battery anode material coated by the LATP based on the lithium bromide and the conductive carbon.
Example 3
The method for preparing the cathode material comprises the following steps:
(1) mixing lithium chloride with a ternary material LiNi1/3Co1/3Mn1/3O2According to the mass ratio of 0.005: 1 is dissolved in acetone phase, and is magnetically stirred for 1 hour at 25 ℃ to obtain uniform lithium chloride-coated ternary solution.
(2) Li to be purchased commercially6.75La3Zr1.75Ta0.25O12(LLZTO) and conductive carbon Super-P according to the mass ratio of 1:1, placing the mixture in a ball milling tank, and ball milling the mixture for 15 hours by a ball mill at the speed of 300rpm/min under the protection of high-purity argon (99.999%) to obtain uniformly mixed powder.
(3) Adding the mixed powder obtained in the step (2) into a ternary solution, and mixing the mixed powder with a ternary material (LiNi)1/3Co1/ 3Mn1/3O2) The mass ratio is 0.1: 1, magnetically stirring uniformly, then carrying out ball milling again, wherein the ball milling speed is 240rpm/min, the duration is 2h, and mechanically milling to obtain a product which is coated by the LLZTO and the conductive carbon for one time.
(4) And (4) putting the product obtained in the step (3) into a blast oven, heating to 80 ℃ in an oxygen atmosphere, staying for 30min, and then heating to 250 ℃ for 30min to prepare the lithium ion battery anode material coated by the LLZTO based on the lithium chloride and the conductive carbon.
Example 4
(1) Mixing lithium silicate with ternary material LiNi1/3Co1/3Mn1/3O2According to the mass ratio of 0.005: 1 is dissolved in the water phase, and is magnetically stirred for 1 hour at 25 ℃ to obtain a uniform lithium silicate coated ternary solution.
(2) Li to be purchased commercially6.1La3Zr1.75Al0.2Ta0.25O12(LLZATO) and conductive carbon Super-P according to the mass ratio of 1:1, placing the mixture in a ball milling tank, and ball milling the mixture for 15 hours by a ball mill at the speed of 300rpm/min under the protection of high-purity argon (99.999%) to obtain uniformly mixed powder.
(3) Adding the mixed powder obtained in the step (2) into a ternary solution, and mixing the mixed powder with a ternary material matrix (LiNi)1/ 3Co1/3Mn1/3O2) The mass ratio is 0.1: 1, magnetically stirring uniformly, then carrying out ball milling again, wherein the ball milling speed is 240rpm/min, the duration is 2h, and mechanically milling to obtain a product which is coated by LLZATO and conductive carbon together.
(4) And (4) putting the product obtained in the step (3) into a blast oven, heating to 80 ℃ in an oxygen atmosphere, staying for 30min, and then heating to 250 ℃ for 30min to prepare the lithium ion battery anode material co-coated by the LLZATO based on the lithium silicate and the conductive carbon.
Example 5
The method for preparing the cathode material comprises the following steps:
(1) lithium iodide is mixed with commercially available lithium nickel manganese oxide material LiNi0.5Mn1.5O4Mixing the mixture into an ethanol phase according to the mass ratio of 0.0025:1, and magnetically stirring the mixture for 30min at 25 ℃ to obtain lithium iodide coated lithium nickel manganese oxide solution.
(2) The mass ratio of LATP to conductive carbon Super-P is 1:1, placing the mixture in a ball milling tank, and ball milling the mixture for 2 hours by a ball mill at the speed of 100rpm/min under the protection of high-purity argon (99.999%) to obtain uniformly mixed powder.
(3) Adding the mixed powder in the step (2) into the solution in the step (1), wherein the mass ratio of the mixed powder to the lithium nickel manganese oxide powder is 0.05: 1, magnetically stirring uniformly, then carrying out ball milling again, wherein the ball milling speed is 240rpm/min, the duration time is 2h, and mechanically milling to obtain a product coated by both LATP and conductive carbon.
(4) And (4) putting the product obtained in the step (3) into an oven, heating to 80 ℃ for 30min, heating to 250 ℃ for 30min, and preparing the lithium ion battery anode material LNMO-LATP @ C coated by the LATP based on lithium iodide and conductive carbon.
Example 6
The method for preparing the cathode material comprises the following steps:
(1) lithium bromide and a commercially available lithium nickel manganese oxide material LiNi0.5Mn1.5O4According to the mass ratio of 0.0025:1, mixing the mixture into an ethanol phase, and magnetically stirring the mixture for 30min at 25 ℃ to obtain the lithium nickel manganese oxide material coated by the lithium bromide.
(2) The mass ratio of LATP to conductive carbon Super-P is 1:1, placing the mixture in a ball milling tank, and ball milling the mixture for 2 hours by a ball mill at the speed of 100rpm/min under the protection of high-purity argon (99.999%) to obtain uniformly mixed powder.
(3) Adding the mixed powder in the step (2) into the solution in the step (1), wherein the mass ratio of the mixed powder to the lithium nickel manganese oxide powder is 0.05: 1, magnetically stirring uniformly, then carrying out ball milling again, wherein the ball milling speed is 240rpm/min, the duration time is 2h, and mechanically milling to obtain a product coated by both LATP and conductive carbon.
(4) And (4) putting the product obtained in the step (3) into an oven, heating to 80 ℃ for 30min, heating to 250 ℃ for 30min, and preparing the lithium ion battery anode material coated by the LATP based on the lithium bromide and the conductive carbon.
Example 7
The method for preparing the cathode material comprises the following steps:
(1) lithium chloride and a commercially available lithium nickel manganese oxide material LiNi0.5Mn1.5O4According to the mass ratio of 0.0025:1, mixing the mixture into an acetone phase, and magnetically stirring the mixture for 30min at the temperature of 25 ℃ to obtain lithium nickel manganese oxide solution coated by lithium chloride.
(2) Will) Li6.75La3Zr1.75Ta0.25O12(LLZTO) and conductive carbon Super-P according to the mass ratio of 1:1, placing the mixture in a ball milling tank, and ball milling the mixture for 15 hours by a ball mill at the speed of 300rpm/min under the protection of high-purity argon (99.999%) to obtain uniformly mixed powder.
(3) Adding the mixed powder in the step (2) into the solution in the step (1), wherein the mass ratio of the mixed powder to the lithium nickel manganese oxide powder is 0.05: 1, magnetically stirring uniformly, then carrying out ball milling again, wherein the ball milling speed is 240rpm/min, the duration is 2h, and mechanically milling to obtain a product which is coated by the LLZTO and the conductive carbon for one time.
(4) And (4) putting the product obtained in the step (3) into an oven, heating to 80 ℃ for 30min, heating to 250 ℃ for 30min, and preparing the lithium ion battery anode material coated by the lithium chloride-based LLZTO and the conductive carbon.
Example 8
The method for preparing the cathode material comprises the following steps:
(1) lithium hexafluorophosphate and a commercially available lithium nickel manganese oxide material LiNi0.5Mn1.5O4According to the mass ratio of 1: 0.0025, and magnetically stirring at 25 ℃ for 30min to obtain lithium nickel manganese oxide solution coated by lithium hexafluorophosphate.
(2) Will) Li7La3Zr2O12(LLZO) and conductive carbon Super-P in a mass ratio of 1:1, placing the mixture in a ball milling tank, and ball milling the mixture for 15 hours by a ball mill at the speed of 300rpm/min under the protection of high-purity argon (99.999%) to obtain uniformly mixed powder.
(3) Adding the mixed powder in the step (2) into the solution in the step (1), wherein the mass ratio of the mixed powder to the lithium nickel manganese oxide powder is 0.05: 1, magnetically stirring uniformly, then carrying out ball milling again, wherein the ball milling speed is 240rpm/min, the duration is 2h, and mechanically milling to obtain a product which is coated by the LLZO and the conductive carbon together.
(4) And (4) putting the product obtained in the step (3) into an oven, heating to 80 ℃ for 30min, heating to 250 ℃ for 30min, and preparing the lithium ion battery anode material coated by the LLZO based on lithium hexafluorophosphate and the conductive carbon.
Example 9
(1) Mixing lithium bromide with lithium cobaltate (LiCoO)2) The powder is mixed according to the mass ratio of 0.005: 1 is dissolved in ethanol phase, and is magnetically stirred for 1 hour at 25 ℃ to obtain uniform lithium bromide coated lithium cobaltate solution.
(2) The LATP was placed in a ball mill jar and ball milled for 2h at 100rpm/min under the protection of high purity argon (99.999%) to obtain a uniformly mixed powder.
(3) Adding the mixed powder of the step (2) into the solution of the step (1), wherein the mixed powder comprises LATP powder and lithium cobaltate (LiCoO)2) Powder mass ratio of 0.05: 1, magnetically stirring uniformly, then carrying out ball milling again, wherein the ball milling speed is 240rpm/min, the duration time is 2h, and mechanically milling to obtain a product coated by the LATP for one time.
(4) And (4) putting the product obtained in the step (3) into a blast oven, heating to 80 ℃ in an oxygen atmosphere, staying for 30min, and then heating to 250 ℃ for 30min to prepare the lithium ion battery anode material coated by the LATP based on the lithium bromide.
Comparative example 1
This comparative example was the same as that used in example 1LiNi as a non-coated positive electrode material1/3Co1/3Mn1/3O2And (6) comparing.
Testing and analyzing:
the products obtained in all the above comparative examples and examples were subjected to scanning electron microscopy and X-ray diffraction analysis.
1) The electron microscopic scan was performed on the sample of example 1, and the results are shown in fig. 1 and 2. It can be seen from the figure that the surface of the active positive electrode material substrate is uniformly covered with a layer of the coating substance.
2) X-ray analysis was performed on the sample in example 1, and it was confirmed that the coating did not change the layered structure of the positive electrode material.
All the positive electrode coating materials are assembled into button cells, including a liquid battery (implementation method one) and a solid battery (implementation method two), and electrochemical performance analysis is carried out after the button cells are assembled.
The implementation method comprises the following steps:
the implementation method comprises the following steps:
the materials after coating and before coating in the above examples and comparative examples are respectively made into positive pole pieces, and button liquid lithium ion batteries are made for performance comparison. Wherein the positive pole comprises the following components: active substance: conductive carbon: binder 8: 1: celgard2500 is used as a battery diaphragm, and a lithium plate is used as a negative electrode. At 1mol/L LiPF6(EC: EMC: DMC 1:1:1) is an electrolyte.
The implementation method II comprises the following steps:
the materials after coating and before coating in the above examples and comparative examples are respectively made into positive pole pieces, and all-solid-state lithium ion batteries are made for performance comparison. The battery includes a positive electrode, a negative electrode, and a solid electrolyte sheet positioned between the positive and negative electrodes. The mass ratio of active substances, solid electrolyte and conductive carbon in the positive electrode is 8: 1:1:1, the lithium sheet is a negative electrode, and the solid electrolyte layer is Li1.3Al0.3Ti1.7P3O12。
Results and analysis:
the microstructures of fig. 1 and 2 demonstrate that the method provided by the present invention can indeed form a uniform coating layer on the surface of the positive electrode material. The X-ray diffraction profile analysis of fig. 3 shows that the coating does not change the crystalline structure of the material. Fig. 4 shows that the coated samples show higher discharge capacity and stability than the uncoated samples, both at high and low rates, between charge and discharge voltages of 2.75-4.4. Under 0.1C, the specific capacity of the material is improved by about 10mAh/g by the first charge-discharge multiplying power, which shows that the material capacity can be properly improved by coating, and the coating has a positive effect on the stability of the material in the charge-discharge process.
The cell was subjected to charge and discharge tests (test voltage range 2.75-4.2V) at a temperature of 25 c, as well as electrochemical impedance and cyclic voltammetry tests. The performance tests are shown in table 1:
TABLE 1
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any modification, equivalent replacement, and improvement made by those skilled in the art within the technical scope of the present invention should be included in the scope of the present invention.
Claims (10)
1. A preparation method of a lithium battery core-shell cathode material is characterized by comprising the following steps:
s1, dissolving lithium salt and a lithium battery positive electrode material matrix in a solvent, and uniformly mixing to obtain a lithium salt-coated ternary solution;
s2, ball-milling solid electrolyte and/or conductive carbon powder to obtain superfine powder;
the solid electrolyte comprises Li1+pAlpGe2-p(PO4)3、Li3qLa2/3-qTiO3、LiZr2-rTir(PO4)3、Li1+ mAlmTi2-m(PO4)3、Li7-2n-jAnLa3Zr2-jXjO12、Li7-2n-2jAnLa3Zr2-jZjO12、Li3S4、Li4-tM1-tNtS4、Li2S-P2S5、Li2S-SiS2、Li2S-B2S3Wherein M is Ge, Si, N is P, A1, Zn, 0 < p < 2, 0 < q < 2/3, 0 < r < 2, 0 < M < 2, 0 < t < 1, 0 < N < 3, 0 < j < 2, wherein A is Ge or Al, X is Nb or Ta, Z is Te or W; the lithium salt includes LiI, LiBr, LiCl, LiF, Li3PO4、LiTFSI、LiPF6、LiBF4、LiClO4、LiCF3SO3、LiN(CF3SO2)2、LiBOB、Li2SiO4One or more of;
s3, adding the powder obtained in the step S2 into a lithium salt-coated ternary solution, and stirring and ball-milling to obtain a lithium salt and solid electrolyte and/or conductive carbon co-coated product;
s4, calcining the co-coated product obtained in the step S3 in an oxygen or inert gas atmosphere, and cooling the sintered product to room temperature after sintering is completed to obtain a finished product with surface stable structures among particles.
2. The method of claim 1, wherein: in step S1, the lithium battery positive electrode material substrate includes: ternary Li1+zNixCoyD1-x-y-sEsO2Nickel manganese spinel LiNi0.5Mn1.5O4Lithium cobaltate Li1+zCo1-sEsO2Rich in lithium manganese tLi2MnO3·(1-t)Li1+zNixCoyMn1-x-y-sEsO2Lithium iron manganese phosphate-based Li1+zFexMn1-x-sEsPO4Lithium manganate Li1+zMn2- sEsO4Lithium iron phosphate Li1+zFe1-sEsPO4Wherein 0 is<x<1，0<y<1，0≤s<0.1，0≤z<0.1，0<x+y+s<1，0<t<1, D is Mn or Al, E is one of Ti, Zr, Nb, La, V and Mg; the particle size of the powder of the lithium battery anode material matrix after ball milling is 0.4-20 μm.
3. The method of claim 1, wherein: in step S1, the solvent is one of water, N-methylpyrrolidone, Propylene Carbonate (PC), Ethylene Carbonate (EC), diethyl carbonate (DEC), dimethyl carbonate (DMC), Ethyl Methyl Carbonate (EMC), Methyl Formate (MF), Methyl Acetate (MA), Ethyl Acetate (EA), Methyl Propionate (MP), and a tetrahydrofuran solution of methanol, ethanol, ethylene glycol, amyl alcohol, ethyl ether, acetonitrile, acetone, pyridine, tetrahydrofuran, dimethylformamide, N-methylformamide, lithium borohydride.
4. The method of claim 1, wherein: the mass ratio of the lithium battery anode material matrix to the lithium salt to the solid electrolyte to the conductive carbon is 1:0.0002-0.08:0.02-0.08: 0.002-0.8.
5. The method of claim 1, wherein: in the step S2, the conductive carbon is conductive carbon Super-P, and the particle size is 20-100 nm.
6. The method of claim 1, wherein: in the step S3, ball milling is performed until the solvent in the mixed slurry is completely volatilized, and the slurry is in a powder shape.
7. The method of claim 1, wherein: in the step S3, the ball milling speed is 100-300rpm/min, and the milling time is 1-3 h.
8. The method of claim 1, wherein: in the step S4, the calcination temperature is 100-350 ℃.
9. A lithium battery core-shell cathode material is characterized in that: prepared by the method of any one of claims 1 to 8, the core is the positive electrode material of the lithium battery, and the shell is a composite conductive network consisting of solid electrolyte, lithium salt and/or conductive carbon.
10. A liquid or all solid state lithium battery characterized by: the lithium battery core-shell cathode material is prepared by the lithium battery core-shell cathode material of claim 9.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114620775A (en) * | 2022-03-15 | 2022-06-14 | 北京理工大学 | Double-anion co-doped lithium-rich manganese-based composite material, preparation method and application |
| CN114678500A (en) * | 2022-03-21 | 2022-06-28 | 北京卫蓝新能源科技有限公司 | Composite coated nickel-rich cathode material and preparation method and application thereof |
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102244257A (en) * | 2011-06-15 | 2011-11-16 | 清华大学深圳研究生院 | High-temperature manganic acid lithium cathode material and preparation method thereof |
| CN102569726A (en) * | 2010-12-30 | 2012-07-11 | 中国电子科技集团公司第十八研究所 | Method for preparing lithium ion battery anode material coated with metal ions |
| CN102738451A (en) * | 2012-07-13 | 2012-10-17 | 河南师范大学 | Modified positive electrode material of lithium ion battery and preparation method of modified positive electrode material |
| CN104037407A (en) * | 2014-05-22 | 2014-09-10 | 北大先行科技产业有限公司 | Lithium cobalt oxide compound material coated with lithium super-Ion conductor and preparation method thereof |
| CN106450259A (en) * | 2015-08-22 | 2017-02-22 | 天津华夏泓源实业有限公司 | Preparation method for improving electrical property of positive electrode material LiCoO2 |
| CN108054378A (en) * | 2017-12-29 | 2018-05-18 | 中国科学院物理研究所 | Lithium battery composite positive pole with nucleocapsid and preparation method thereof |
| CN108448084A (en) * | 2018-03-09 | 2018-08-24 | 成都新柯力化工科技有限公司 | A kind of two-dimensional layered structure anode material of lithium battery and preparation method |
| CN110165236A (en) * | 2019-06-05 | 2019-08-23 | 青岛大学 | A kind of preparation method and applications of bilayer oxide solid electrolyte |
| CN111342050A (en) * | 2020-03-06 | 2020-06-26 | 上海汽车集团股份有限公司 | Coating method for improving ionic conductivity of lithium ion battery anode material and coating modified anode material |
| CN112397765A (en) * | 2019-08-16 | 2021-02-23 | 通用汽车环球科技运作有限责任公司 | Solid-state battery having electrode containing electronically conductive polymer |
-
2021
- 2021-09-13 CN CN202111070842.0A patent/CN113871588B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102569726A (en) * | 2010-12-30 | 2012-07-11 | 中国电子科技集团公司第十八研究所 | Method for preparing lithium ion battery anode material coated with metal ions |
| CN102244257A (en) * | 2011-06-15 | 2011-11-16 | 清华大学深圳研究生院 | High-temperature manganic acid lithium cathode material and preparation method thereof |
| CN102738451A (en) * | 2012-07-13 | 2012-10-17 | 河南师范大学 | Modified positive electrode material of lithium ion battery and preparation method of modified positive electrode material |
| CN104037407A (en) * | 2014-05-22 | 2014-09-10 | 北大先行科技产业有限公司 | Lithium cobalt oxide compound material coated with lithium super-Ion conductor and preparation method thereof |
| CN106450259A (en) * | 2015-08-22 | 2017-02-22 | 天津华夏泓源实业有限公司 | Preparation method for improving electrical property of positive electrode material LiCoO2 |
| CN108054378A (en) * | 2017-12-29 | 2018-05-18 | 中国科学院物理研究所 | Lithium battery composite positive pole with nucleocapsid and preparation method thereof |
| CN108448084A (en) * | 2018-03-09 | 2018-08-24 | 成都新柯力化工科技有限公司 | A kind of two-dimensional layered structure anode material of lithium battery and preparation method |
| CN110165236A (en) * | 2019-06-05 | 2019-08-23 | 青岛大学 | A kind of preparation method and applications of bilayer oxide solid electrolyte |
| CN112397765A (en) * | 2019-08-16 | 2021-02-23 | 通用汽车环球科技运作有限责任公司 | Solid-state battery having electrode containing electronically conductive polymer |
| CN111342050A (en) * | 2020-03-06 | 2020-06-26 | 上海汽车集团股份有限公司 | Coating method for improving ionic conductivity of lithium ion battery anode material and coating modified anode material |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114620775A (en) * | 2022-03-15 | 2022-06-14 | 北京理工大学 | Double-anion co-doped lithium-rich manganese-based composite material, preparation method and application |
| CN114620775B (en) * | 2022-03-15 | 2023-03-24 | 北京理工大学 | Double-anion co-doped lithium-rich manganese-based composite material, preparation method and application |
| CN114678500A (en) * | 2022-03-21 | 2022-06-28 | 北京卫蓝新能源科技有限公司 | Composite coated nickel-rich cathode material and preparation method and application thereof |
| CN114709398A (en) * | 2022-04-17 | 2022-07-05 | 晖阳(贵州)新能源材料有限公司 | Sulfur-containing fast ion conductor coated graphite composite material and preparation method thereof |
| WO2023201526A1 (en) * | 2022-04-19 | 2023-10-26 | 宁德新能源科技有限公司 | Positive electrode material, electrochemical device and electronic device |
| CN114824280A (en) * | 2022-06-27 | 2022-07-29 | 蚂蚁新能源科技(天津)有限公司 | Composite positive electrode material for lithium ion battery dry-method electrode and preparation method and application thereof |
| CN114824280B (en) * | 2022-06-27 | 2022-09-06 | 蚂蚁新能源科技(天津)有限公司 | Composite positive electrode material for lithium ion battery dry-method electrode and preparation method and application thereof |
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