CN113036137A - Lithium ion battery cathode material and preparation method and application thereof - Google Patents

Lithium ion battery cathode material and preparation method and application thereof Download PDF

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CN113036137A
CN113036137A CN202110244683.5A CN202110244683A CN113036137A CN 113036137 A CN113036137 A CN 113036137A CN 202110244683 A CN202110244683 A CN 202110244683A CN 113036137 A CN113036137 A CN 113036137A
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lithium ion
ion battery
silicon
negative electrode
cathode material
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刘朗
李冰
梁世硕
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Kunshan Bao Innovative Energy Technology Co Ltd
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Abstract

The invention relates to a lithium ion battery cathode material and a preparation method and application thereof. The lithium ion battery cathode material comprises a silicon-based substrate and a titanium-based compound coating layer coated on the surface of the silicon-based substrate, wherein graphene and a graphite-like structure are doped in the titanium-based compound coating layer. According to the lithium ion battery cathode material, the titanium-based compound coating layer can reduce the surface defects of the silicon-based substrate, so that the side reaction of the lithium ion battery cathode material and electrolyte at high temperature is reduced, and meanwhile, the titanium-based compound has good thermal stability and can greatly improve the high-temperature stability of the lithium ion battery cathode material; the graphene and graphite-like structures can improve the conductivity of the lithium ion battery cathode material, so that the first coulombic efficiency and the first discharge capacity of the lithium ion battery cathode material are improved, the impedance of the lithium ion battery cathode material and the heat productivity in the charging and discharging processes are reduced, and the high-temperature storage performance of the lithium ion battery cathode material is improved.

Description

Lithium ion battery cathode material and preparation method and application thereof
Technical Field
The invention relates to the technical field of lithium ion batteries, in particular to a lithium ion battery cathode material and a preparation method and application thereof.
Background
With the ever-increasing demand for high-performance energy storage devices, the energy field, particularly lithium ion batteries, has attracted a great deal of attention. The lithium ion battery cathode material widely used in industry is graphite carbon material. The graphite negative electrode material has excellent conductivity and good chemical stability, and is an ideal carbon matrix as an active material of a lithium ion battery. At present, 90% of lithium ion battery cathode materials adopt graphite cathodes, the graphite cathodes have the advantages of high conductivity and stability, but the current development is close to the theoretical maximum value of the specific capacity-372 mAh/g. Experimental research finds that silicon is the anode material with the largest theoretical capacity at present, when Li4.4Si is formed in the silicon by lithium, the specific capacity is up to 4200mAh/g and is far higher than the theoretical capacity of graphite, and the silicon has the advantages of low lithium intercalation potential and low cost. Therefore, the silicon-based negative electrode is expected to replace graphite to become a negative electrode material of a next-generation lithium ion battery.
The silicon-based negative electrode material is more and more widely applied as a negative electrode of a lithium battery, has a trend of increasing year by year in the aspects of power, 3C digital and energy storage negative electrode materials, and particularly has a wide application prospect in the field of energy storage. With the gradual expansion of the energy storage market, the dosage of the silicon-based negative electrode material tends to increase explosively. At present, the research on silicon-based anode materials mainly focuses on silicon-carbon anode materials and silicon-oxygen anode materials, however, the silicon-carbon anode materials and the silicon-oxygen anode materials have poor electrical conductivity, low material capacity and first efficiency, and general high-temperature storage performance, and the large-scale application of the silicon-carbon anode materials in the field of energy storage is limited. The current research mainly reduces surface defects in a carbon coating mode and improves the material capacity, the first effect, the high-temperature storage and other performances. However, the surface carbon layer is used for coating and modifying, so that an additional functional group is introduced to the surface of the silicon-based negative electrode material, the side reaction of the negative electrode material and electrolyte at a high temperature is aggravated, the consumption of the electrolyte is accelerated, and the cycle performance is reduced. Therefore, there is a need to improve the high-temperature storage performance of silicon-based anode materials through other approaches.
Disclosure of Invention
Therefore, the lithium ion battery cathode material, the preparation method and the application thereof are needed to solve the problem of how to improve the high-temperature storage performance of the silicon-based cathode material.
The lithium ion battery negative electrode material comprises a silicon-based substrate and a titanium-based compound coating layer coated on the surface of the silicon-based substrate, wherein graphene and a graphite-like structure are doped in the titanium-based compound coating layer.
By applying the lithium ion battery cathode material of the technical scheme of the invention, the titanium-based compound coating layer can reduce the surface defects of the silicon-based substrate, so that the side reaction of the lithium ion battery cathode material and electrolyte at high temperature is reduced, and meanwhile, the titanium-based compound has good thermal stability and can greatly improve the high-temperature stability of the lithium ion battery cathode material; furthermore, the graphene and graphite-like structures can improve the conductivity of the lithium ion battery cathode material, so that the first coulomb efficiency and the first discharge capacity of the lithium ion battery cathode material are improved, the impedance of the lithium ion battery cathode material and the heat productivity in the charging and discharging processes are reduced, the consumption of electrolyte at high temperature is reduced, and the high-temperature storage performance of the lithium ion battery cathode material is improved.
In one embodiment, the silicon-based substrate is selected from at least one of a silicon monoxide, a nano-silicon, and a silicon carbon. The silicon-based base materials are used for the lithium ion battery cathode material, and are beneficial to obtaining the cathode material with larger specific capacity.
In one embodiment, the silicon-based substrate has a particle size of 50nm to 20 μm. More preferably, the particle size of the silicon-based base material is 1 μm to 8 μm.
In one embodiment, the median particle size of the lithium ion battery negative electrode material is 1-30 μm. More preferably, the median particle diameter of the lithium ion battery negative electrode material is 3 μm to 10 μm.
The preparation method of the lithium ion battery anode material comprises the following steps:
uniformly mixing graphene, a titanium source and an organic solvent to obtain a dispersion liquid;
adding a silicon-based base material into the dispersion liquid, fully mixing, and then drying to obtain dried powder; and
heating the dried powder to 600-1200 ℃ in a reducing atmosphere, and sintering to obtain a lithium ion battery negative electrode material; the lithium ion battery negative electrode material comprises a silicon-based substrate and a titanium-based compound coating layer coated on the surface of the silicon-based substrate, wherein graphene and a graphite-like structure are doped in the titanium-based compound coating layer.
According to the preparation method of the lithium ion battery cathode material, the titanium source, the graphene and the silicon-based substrate are uniformly mixed and then dried, and then sintered in a reducing atmosphere to directly obtain the titanium-based compound coated silicon-based cathode material with good high-temperature storage performance through one-step reaction to serve as the lithium ion battery cathode material, so that the steps are simple, and the equipment requirement is low. The lithium ion battery cathode material has the advantages of simple preparation process, good doping and coating effects, easiness in popularization, good high-temperature storage performance, good conductivity, high capacity and first efficiency and the like.
In one embodiment, the mass ratio of the graphene, the titanium source and the silicon-based substrate is (0.0001-1): (0.5-30): 100.
In one embodiment, the mass ratio of the graphene, the titanium source and the silicon-based substrate is (0.01-0.5): (2-10): 100.
In one embodiment, the titanium source is selected from at least one of tetrabutyl titanate and isopropyl titanate.
In one embodiment, the organic solvent is selected from at least one of methanol, ethanol, isopropanol, and propanol. Further preferably, the organic solvent is selected from methanol or ethanol.
In one embodiment, the dried powder is heated to 800 ℃ to 1000 ℃ under a reducing atmosphere.
In one embodiment, the reducing atmosphere is selected from at least one of argon-hydrogen mixed gas, argon-methane mixed gas and argon-carbon monoxide mixed gas.
The lithium ion battery of an embodiment comprises the lithium ion battery negative electrode material.
By applying the lithium ion battery of the technical scheme, the titanium-based compound coating layer in the lithium ion battery cathode material can reduce the surface defects of the silicon-based substrate, so that the side reaction of the lithium ion battery cathode material and the electrolyte at high temperature is reduced, and meanwhile, the titanium-based compound has good thermal stability and can greatly improve the high-temperature stability of the lithium ion battery cathode material; furthermore, the graphene and graphite-like structures can improve the conductivity of the lithium ion battery cathode material, so that the first coulomb efficiency and the first discharge capacity of the lithium ion battery cathode material are improved, the impedance of the lithium ion battery cathode material and the heat productivity in the charging and discharging processes are reduced, the consumption of electrolyte at high temperature is reduced, the high-temperature storage performance of the lithium ion battery cathode material is improved, and the overall performance of the lithium ion battery is improved.
Drawings
Fig. 1 is a flowchart of a method for preparing a negative electrode material for a lithium ion battery according to an embodiment of the present invention;
FIG. 2 is a Scanning Electron Microscope (SEM) image of the negative electrode material of the lithium ion battery prepared in example 1;
fig. 3 is a test chart of electrochemical performance of the negative electrode materials of the lithium ion batteries prepared in examples 1 to 3 and comparative example 1.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
The lithium ion battery cathode material comprises a silicon-based substrate and a titanium-based compound coating layer coated on the surface of the silicon-based substrate, wherein the titanium-based compound coating layer is doped with graphene and a graphite-like structure.
Wherein, the graphite-like structure in the titanium-based compound coating layer is formed by partial reduction of the titanium-based compound by the reducing atmosphere and the graphene, and the graphite-like structure can be Ti-O-C, Ti-C or Ti-C-O, etc. The graphite-like structure can improve the conductivity of the lithium ion battery cathode material, so that the first coulombic efficiency and the first discharge capacity of the lithium ion battery cathode material are improved, the impedance of the lithium ion battery cathode material and the heat productivity in the charge-discharge process are reduced, the consumption of electrolyte at high temperature is reduced, and the high-temperature storage performance of the lithium ion battery cathode material is improved.
The graphene doped in the titanium-based compound coating layer can be any graphene, such as single-layer graphene, multi-layer graphene or a combination of the two. The graphene can also improve the conductivity of the lithium ion battery cathode material, so that the first coulombic efficiency and the first discharge capacity of the lithium ion battery cathode material are improved, the impedance of the lithium ion battery cathode material and the heat productivity in the charge-discharge process are reduced, the consumption of electrolyte at high temperature is reduced, and the high-temperature storage performance of the lithium ion battery cathode material is improved.
According to the lithium ion battery cathode material of the embodiment, the titanium-based compound coating layer can reduce the defects on the surface of the silicon-based substrate, the conductivity of the lithium ion battery cathode material is improved, and the titanium-based compound coating layer has good thermal stability, so that the high-temperature stability of the lithium ion battery cathode material can be greatly improved, the side reaction with electrolyte is reduced, and the high-temperature storage performance of the lithium ion battery cathode material is obviously improved.
In one embodiment, the silicon-based substrate is selected from at least one of a silicon monoxide, a nano-silicon, and a silicon carbon. The silicon-based base materials are used for the lithium ion battery cathode material, and are beneficial to obtaining the cathode material with larger specific capacity.
In one embodiment, the silicon-based substrate has a particle size of 50nm to 20 μm. More preferably, the particle size of the silicon-based base material is 1 μm to 8 μm.
In one embodiment, the median particle size of the lithium ion battery negative electrode material is 1 μm to 30 μm. More preferably, the median particle diameter of the lithium ion battery negative electrode material is 3 μm to 10 μm.
By applying the lithium ion battery cathode material of the technical scheme of the invention, the titanium-based compound coating layer can reduce the surface defects of the silicon-based substrate, so that the side reaction of the lithium ion battery cathode material and electrolyte at high temperature is reduced, and meanwhile, the titanium-based compound has good thermal stability and can greatly improve the high-temperature stability of the lithium ion battery cathode material; furthermore, the graphene and graphite-like structures can improve the conductivity of the lithium ion battery cathode material, so that the first coulomb efficiency and the first discharge capacity of the lithium ion battery cathode material are improved, the impedance of the lithium ion battery cathode material and the heat productivity in the charging and discharging processes are reduced, the consumption of electrolyte at high temperature is reduced, and the high-temperature storage performance of the lithium ion battery cathode material is improved.
Referring to fig. 1, a method for preparing a negative electrode material of a lithium ion battery according to an embodiment of the present invention includes the following steps:
and S10, uniformly mixing the graphene, the titanium source and the organic solvent to obtain a dispersion liquid.
The graphene may be any graphene, such as single-layer graphene, multi-layer graphene, or a combination thereof. The graphene can be dispersed in the dispersing agent and then mixed with other components uniformly.
Wherein the titanium source is used to provide a source of titanium. In one embodiment, the titanium source is selected from at least one of tetrabutyl titanate and isopropyl titanate.
In one embodiment, the mass ratio of the graphene, the titanium source and the silicon-based substrate is (0.0001-1): 0.5-30): 100.
In one embodiment, the mass ratio of the graphene, the titanium source and the silicon-based substrate is (0.01-0.5): 2-10): 100.
In the technical scheme of the invention, the content of the graphene is less, because the graphene has certain viscosity when being added into the organic solvent, the influence on the performance of the lithium ion battery caused by too high viscosity of the dispersion liquid can be avoided.
In one embodiment, the organic solvent is an alcohol solvent. Further, the organic solvent is selected from at least one of methanol, ethanol, isopropanol and propanol. Among them, the organic solvent is preferably methanol or ethanol.
In step S10, the graphene, the titanium source, and the organic solvent may be uniformly mixed by stirring for 1h to 10h, preferably for 1h to 5 h.
S20, adding a silicon-based base material to the dispersion obtained in step S10, mixing them thoroughly, and drying the mixture to obtain a dried powder.
In step S20, the silicon-based substrate and the dispersion may be fully mixed by stirring for 1h to 10h, preferably for 1h to 5 h.
In one embodiment, the silicon-based substrate is selected from at least one of a silicon monoxide, a nano-silicon, and a silicon carbon. The silicon-based base materials are used for the lithium ion battery cathode material, and are beneficial to obtaining the cathode material with larger specific capacity.
In one embodiment, the silicon-based substrate has a particle size of 50nm to 20 μm. More preferably, the particle size of the silicon-based base material is 1 μm to 8 μm.
Among them, the drying method is a method such as stirring and heating evaporation, rotary evaporation, freeze drying or spray drying, and among them, rotary evaporation is preferable.
S30, heating the dried powder obtained in the step S20 to 600-1200 ℃ in a reducing atmosphere, and sintering to obtain the lithium ion battery negative electrode material; the lithium ion battery cathode material comprises a silicon-based substrate and a titanium-based compound coating layer coated on the surface of the silicon-based substrate, wherein graphene and a graphite-like structure are doped in the titanium-based compound coating layer.
In a reducing atmosphere, the whole reaction can be completed in one step by setting a temperature rise curve, the whole preparation process of the lithium ion battery cathode material is carried out in an inert environment, the operation is simple, and the raw materials are economical.
In one embodiment, the dried powder is heated to 800 ℃ to 1000 ℃ under a reducing atmosphere.
In one embodiment, the reducing atmosphere is selected from at least one of argon-hydrogen mixture, argon-methane mixture, and argon-carbon monoxide mixture.
In step S30, the sintering equipment is selected from one of tube carbonization furnace, box carbonization furnace, roller kiln, pusher kiln, CVD furnace, and other sintering equipment.
After sintering treatment, a titanium-based compound coating layer is formed on the surface of the silicon-based substrate, and graphene and graphite-like structures such as Ti-O-C, Ti-C, Ti-C-O and the like formed by reaction in a reducing atmosphere are doped in the titanium-based compound coating layer.
The median particle size of the lithium ion battery negative electrode material prepared by the preparation method is 1-30 μm. More preferably, the median particle diameter of the lithium ion battery negative electrode material is 3 μm to 10 μm.
In addition, the product needs to be subjected to heat preservation treatment in the sintering process. After sintering, the product can be naturally cooled and then taken out for sieving to obtain the sieved lithium ion battery cathode material.
According to the preparation method of the lithium ion battery cathode material, the titanium source, the graphene and the silicon-based substrate are uniformly mixed and then dried, and then sintered in a reducing atmosphere to directly obtain the titanium-based compound coated silicon-based cathode material with good high-temperature storage performance through one-step reaction to serve as the lithium ion battery cathode material, so that the steps are simple, and the equipment requirement is low. The lithium ion battery cathode material has the advantages of simple preparation process, good doping and coating effects, easiness in popularization, good high-temperature storage performance, good conductivity, high capacity and first efficiency and the like.
The lithium ion battery of one embodiment of the invention comprises the lithium ion battery negative electrode material.
By applying the lithium ion battery of the technical scheme, the titanium-based compound coating layer in the lithium ion battery cathode material can reduce the surface defects of the silicon-based substrate, so that the side reaction of the lithium ion battery cathode material and the electrolyte at high temperature is reduced, and meanwhile, the titanium-based compound has good thermal stability and can greatly improve the high-temperature stability of the lithium ion battery cathode material; furthermore, the graphene and graphite-like structures can improve the conductivity of the lithium ion battery cathode material, so that the first coulomb efficiency and the first discharge capacity of the lithium ion battery cathode material are improved, the impedance of the lithium ion battery cathode material and the heat productivity in the charging and discharging processes are reduced, the consumption of electrolyte at high temperature is reduced, the high-temperature storage performance of the lithium ion battery cathode material is improved, and the overall performance of the lithium ion battery is improved.
In order to make the technical solution of the present application more specific, clear and easy to understand by referring to the above implementation, the technical solution of the present application is exemplified, but it should be noted that the content to be protected by the present application is not limited to the following embodiments 1 to 3.
Example 1
Taking 10g of tetrabutyl titanate liquid and 0.06g of single-layer graphene, adding 200mL of ethanol serving as a solvent, and stirring for 3 hours to obtain a dispersion liquid.
100g of a silica negative electrode base material (median particle diameter of 5.5 μm) was added to the dispersion, and after stirring for 3 hours, the mixture was added to a rotary evaporator and rotary-evaporated and dried at 50 ℃ to obtain a dried powder.
And transferring the dried powder into an alumina crucible, putting the alumina crucible and the alumina crucible into a tubular carbonization furnace together, heating the powder to 950 ℃ in an argon-hydrogen mixed gas atmosphere, heating the powder for 2 hours, and then sieving the powder by a 200-mesh sieve to obtain 5% of graphene doped 10% titanium-based compound coated negative electrode material.
Scanning Electron Microscope (SEM) characterization was performed on the titanium-based compound coated negative electrode material prepared in example 1 to obtain fig. 2. As can be seen from fig. 2, the particle size distribution of the titanium-based compound coated negative electrode material prepared in example 1 is relatively uniform, and the coating effect of the titanium-based compound coating on the surface of the silicon-based substrate is relatively good.
Example 2
Taking 5g of tetrabutyl titanate liquid and 0.01g of single-layer graphene, adding 200mL of ethanol as a solvent, and stirring for 3 hours to obtain a dispersion liquid.
100g of a silica negative electrode base material (median particle diameter of 5.5 μm) was added to the dispersion, and after stirring for 3 hours, the mixture was added to a rotary evaporator and rotary-evaporated and dried at 50 ℃ to obtain a dried powder.
And transferring the dried powder into an alumina crucible, putting the alumina crucible and the alumina crucible into a tubular carbonization furnace together, heating the alumina crucible and the tubular carbonization furnace to 900 ℃ in the atmosphere of argon-hydrogen mixed gas, heating the alumina crucible for 2 hours, and then sieving the alumina crucible by a 200-mesh sieve to obtain 1% of graphene doped 5% titanium-based compound coated silicon-based negative electrode material.
Example 3
Taking 15g of tetrabutyl titanate liquid and 0.1g of single-layer graphene, adding 200mL of ethanol as a solvent, and stirring for 3 hours to obtain a dispersion liquid.
100g of a silica negative electrode base material (median particle diameter of 5.5 μm) was added to the dispersion, and after stirring for 3 hours, the mixture was added to a rotary evaporator and rotary-evaporated and dried at 50 ℃ to obtain a dried powder.
Transferring the dried powder into an alumina crucible, putting the alumina crucible into a tubular carbonization furnace, heating the alumina crucible to 900 ℃ in an argon atmosphere, heating the alumina crucible for 2 hours, and then sieving the alumina crucible with a 200-mesh sieve to obtain 10% of graphene doped 15% titanium-based compound coated negative electrode material.
Comparative example 1:
this comparative example is a comparative example to example 1, and provides a lithium ion battery anode material differing from example 1 only in that: the negative electrode material is a silicon-oxygen negative electrode material which is not modified.
And (3) performance testing:
physical properties of the lithium ion battery negative electrode materials of examples 1 to 3 and comparative example 1 were measured, and the results are shown in table 1.
Wherein, the charge and discharge test process is as follows: products prepared in examples 1 to 3 and comparative example 1 are uniformly mixed with SP, CMC and SBR according to a ratio of 90:5:2:3, and then are pulped, coated and rolled, a negative electrode plate is formed on a copper net, then a lithium plate is used as a counter electrode to prepare a button cell, and a charge and discharge test is carried out, wherein the test results are shown in figure 3 and table 1.
Table 1 results of performance test of lithium ion battery negative electrode materials of examples 1 to 3 and comparative example 1
Figure BDA0002963644490000111
As can be seen from Table 1 and FIG. 3, the lithium ion battery negative electrode material of example 1 had a medium particle diameter of 6.92 μm and a specific surface area of 1.85m2Per g, powder conductivity 9.3X 106Mu S/cm, good conductivity; electrochemical tests show that the reversible capacity of the composite material reaches 1531.1mAh/g, the first efficiency is 75.53%, and the powder conductivity test is 9.3 multiplied by 106Mu S/cm, the discharge test capacity is 1236.6mAh/g after being placed at the high temperature of 55 ℃ for 72h, the capacity retention rate is 80.29%, and the high-temperature storage performance is good.
The lithium ion battery negative electrode material of example 2 had a medium particle diameter of 6.21 μm and a specific surface area of 2.36m2Per g, powder conductivity 7.2X 105Mu S/cm, good conductivity; electrochemical tests show that the reversible capacity of the composite material reaches 1412.7mAh/g, the primary efficiency is 73.58%, after the composite material is placed at a high temperature of 55 ℃ for 72h, the discharge test capacity is 930.2mAh/g, the capacity retention rate is 62.56%, and the composite material has excellent high-temperature storage performance.
The lithium ion battery negative electrode material of example 3 had a medium particle diameter of 8.45 μm and a specific surface area of 1.43m2Per g, powder conductivity 8.1X 106Mu S/cm, good conductivity; electrochemical tests show that the reversible capacity of the composite material is 1473.9mAh/g, the primary efficiency is 74.26%, after the composite material is placed at the high temperature of 55 ℃ for 72h, the discharge test capacity is 1225.9mAh/g, the capacity retention rate is 81.18%, and the composite material has excellent high-temperature storage performance.
The lithium ion battery negative electrode material of comparative example 1 had a medium particle diameter of 5.5 μm and a specific surface area of 2.70m2Per g, powder conductivity 2.5X 103Mu S/cm, poor conductivity; electrochemical tests show that the reversible capacity is 782.0mAh/g, the first efficiency is 35.21%, after the material is placed at the high temperature of 55 ℃ for 72 hours, the discharge test capacity is only 188.0mAh/g, the capacity retention rate is 26.90%, and the high-temperature storage performance is poor.
Comparing the performance test results of the lithium ion battery cathode material prepared in the embodiment 1 and the lithium ion battery cathode material prepared in the comparative example 1, it can be seen that the impedance of the lithium ion battery cathode material prepared in the embodiment 1 is obviously reduced, the conductivity is obviously improved, the first coulombic efficiency and the first discharge capacity are both improved, and the high-temperature storage performance is obviously improved due to the fact that the lithium ion battery cathode material prepared in the embodiment 1 is coated with the titanium-based compound and doped with the graphene in a proper proportion. The lithium ion battery cathode material and the preparation method thereof can obviously improve the high-temperature storage performance and the conductivity.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims (10)

1. The lithium ion battery negative electrode material is characterized by comprising a silicon-based substrate and a titanium-based compound coating layer coated on the surface of the silicon-based substrate, wherein graphene and a graphite-like structure are doped in the titanium-based compound coating layer.
2. The lithium ion battery anode material of claim 1, wherein the silicon-based substrate is selected from at least one of a silicon protoxide, a nano-silicon, and a silicon carbon.
3. The negative electrode material of the lithium ion battery according to claim 1, wherein the silicon-based substrate has a particle size of 50nm to 20 μm;
the median particle size of the lithium ion battery negative electrode material is 1-30 μm.
4. A preparation method of a lithium ion battery cathode material is characterized by comprising the following steps:
uniformly mixing graphene, a titanium source and an organic solvent to obtain a dispersion liquid;
adding a silicon-based base material into the dispersion liquid, fully mixing, and then drying to obtain dried powder; and
heating the dried powder to 600-1200 ℃ in a reducing atmosphere, and sintering to obtain a lithium ion battery negative electrode material; the lithium ion battery negative electrode material comprises a silicon-based substrate and a titanium-based compound coating layer coated on the surface of the silicon-based substrate, wherein graphene and a graphite-like structure are doped in the titanium-based compound coating layer.
5. The preparation method of the negative electrode material for the lithium ion battery as claimed in claim 4, wherein the mass ratio of the graphene, the titanium source and the silicon-based substrate is (0.0001-1): 0.5-30): 100.
6. The preparation method of the negative electrode material of the lithium ion battery as claimed in claim 5, wherein the mass ratio of the graphene, the titanium source and the silicon-based substrate is (0.01-0.5): 2-10): 100.
7. The method for preparing the negative electrode material of the lithium ion battery according to claim 4, wherein the titanium source is at least one selected from tetrabutyl titanate and isopropyl titanate.
8. The method for preparing the negative electrode material of the lithium ion battery according to claim 4, wherein the organic solvent is at least one selected from methanol, ethanol, isopropanol and propanol.
9. The preparation method of the lithium ion battery negative electrode material according to claim 4, wherein the dried powder is heated to 800-1000 ℃ in a reducing atmosphere;
the reducing atmosphere is at least one of argon-hydrogen mixed gas, argon-methane mixed gas and argon-carbon monoxide mixed gas.
10. A lithium ion battery, characterized by comprising the lithium ion battery negative electrode material according to any one of claims 1 to 3.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117239105A (en) * 2023-11-14 2023-12-15 比亚迪股份有限公司 Silicon anode material and preparation method thereof, anode piece, battery and electric equipment

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102627320A (en) * 2012-04-25 2012-08-08 中国科学院宁波材料技术与工程研究所 Preparation method for nano titanium dioxide lithium ion battery cathode material
CN102881881A (en) * 2012-10-25 2013-01-16 中国科学院宁波材料技术与工程研究所 Negative pole material of lithium ion battery, preparation method of material and lithium ion battery
CN105742599A (en) * 2016-03-18 2016-07-06 苏州协鑫集成科技工业应用研究院有限公司 Silicon carbon composite material, fabrication method thereof, anode material and battery
CN107623104A (en) * 2017-09-25 2018-01-23 常州市宇科不绣钢有限公司 A kind of structure silicon-based negative material of multi-buffer and preparation method thereof
CN108160064A (en) * 2017-12-25 2018-06-15 中国科学院上海硅酸盐研究所 A kind of graphene/titania composite material and its preparation method and application
CN108470891A (en) * 2018-03-16 2018-08-31 四川大学 The method for preparing silicon-carbon cathode material based on micron silica
CN108878831A (en) * 2018-06-27 2018-11-23 深圳大学 A method of improving silicon based anode material electric conductivity
CN109833862A (en) * 2019-01-22 2019-06-04 太原理工大学 A kind of preparation method of redox graphene/titanium dioxide double shells hollow sphere composite photocatalyst material

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102627320A (en) * 2012-04-25 2012-08-08 中国科学院宁波材料技术与工程研究所 Preparation method for nano titanium dioxide lithium ion battery cathode material
CN102881881A (en) * 2012-10-25 2013-01-16 中国科学院宁波材料技术与工程研究所 Negative pole material of lithium ion battery, preparation method of material and lithium ion battery
CN105742599A (en) * 2016-03-18 2016-07-06 苏州协鑫集成科技工业应用研究院有限公司 Silicon carbon composite material, fabrication method thereof, anode material and battery
CN107623104A (en) * 2017-09-25 2018-01-23 常州市宇科不绣钢有限公司 A kind of structure silicon-based negative material of multi-buffer and preparation method thereof
CN108160064A (en) * 2017-12-25 2018-06-15 中国科学院上海硅酸盐研究所 A kind of graphene/titania composite material and its preparation method and application
CN108470891A (en) * 2018-03-16 2018-08-31 四川大学 The method for preparing silicon-carbon cathode material based on micron silica
CN108878831A (en) * 2018-06-27 2018-11-23 深圳大学 A method of improving silicon based anode material electric conductivity
CN109833862A (en) * 2019-01-22 2019-06-04 太原理工大学 A kind of preparation method of redox graphene/titanium dioxide double shells hollow sphere composite photocatalyst material

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117239105A (en) * 2023-11-14 2023-12-15 比亚迪股份有限公司 Silicon anode material and preparation method thereof, anode piece, battery and electric equipment
CN117239105B (en) * 2023-11-14 2024-02-27 比亚迪股份有限公司 Silicon anode material and preparation method thereof, anode piece, battery and electric equipment

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