CN114212785A - Negative electrode material and preparation method thereof, negative plate and lithium ion battery - Google Patents
Negative electrode material and preparation method thereof, negative plate and lithium ion battery Download PDFInfo
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Abstract
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a negative electrode material and a preparation method thereof, a negative electrode plate and a lithium ion battery6And dissolving the powder and the graphite material in a solvent, stirring and mixing, stirring and centrifuging, and calcining in an inert gas environment to obtain the cathode material. The invention relates to a preparation method of a negative electrode material, and LiPF6The in-situ coating method can ensure that the generated LiF layer is combined with the graphite more tightlyThe problem of weak mechanical strength of the SEI film is solved, meanwhile, the compatibility of graphite and a negative electrode material is improved, the generation of the SEI film is reduced, and the first charge-discharge efficiency of the electrode material is improved; meanwhile, the graphite has high lithium ion conductivity, can improve the lithium ion de-intercalation rate on the graphite surface, and improves the cycle performance and the rate performance.
Description
Technical Field
The invention belongs to the technical field of lithium ion batteries, and particularly relates to a negative electrode material and a preparation method thereof, a negative electrode sheet and a lithium ion battery.
Background
In order to solve the increasingly severe environmental problems, the performance requirements of lithium ion batteries are increasing. As a lithium ion battery cathode material which is most widely commercialized, graphite firmly controls market advantages due to the advantages of high electronic conductivity, stable voltage platform, abundant resources, low price and the like. But the graphite cathode has the defects of low ionic conductivity, poor compatibility with electrolyte and the like.
In the first charge-discharge process of the lithium ion battery, namely before lithium ions begin to be embedded into the graphite electrode, the electrode material and the organic electrolyte undergo a reduction decomposition reaction on a solid-liquid interface to form an SEI solid electrolyte interface film covering the electrode material. The generation of the SEI film consumes part of lithium ions, so that the charge-discharge irreversible capacity of the whole battery is increased, and the charge-discharge efficiency of the electrode material is reduced. In addition, the SEI film on the surface of the graphite is stressed and stretched in the expansion and contraction processes of the graphite cathode, and the structure is damaged in the deformation process because the strength of the SEI film is not high; the electrolyte is decomposed and consumed to generate a new SEI film at the gap due to the direct contact of the electrolyte and the graphite, the electrolyte is consumed due to the repeated occurrence of the above processes in the charging and discharging processes of the lithium ion battery, and in addition, the thicker the SEI film formed on the surface of the graphite is, the higher the surface impedance of the negative electrode is, and the lower the cycle performance and the rate capability of the whole battery are.
Disclosure of Invention
One of the objects of the present invention is: aiming at the defects of the prior art, the preparation method of the negative electrode material is provided for solving the problems of weak mechanical strength, poor cycle performance and poor rate performance of the SEI film.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of a negative electrode material, which is prepared by mixing LiPF6And dissolving the powder and the graphite material in a solvent, stirring and mixing, stirring and centrifuging, and calcining to obtain the cathode material.
The invention adopts an in-situ coating mode and utilizes the LiPF with low price6And coating a layer of LiF on the surface of the prepared graphite material. The LiF coating layer can improve the compatibility of the graphite cathode material and the electrolyte; in addition, the LiF has high strength, can keep the structure of the graphite cathode complete and not damaged in the expansion and contraction processes of the graphite cathode, and improves the cycle performance and the rate capability of the graphite cathode.
The invention has simple operation and simple required equipment. LiPF6The in-situ coating method can ensure that the generated LiF layer is combined with graphite more tightly, improve the compatibility of the graphite and a negative electrode material, reduce the generation of an SEI (solid electrolyte interphase) film and improve the first charge-discharge efficiency of the electrode material; meanwhile, the graphite has higher lithium ion conductivity, and can improve the lithium ion de-intercalation rate on the graphite surface. The inert gas includes any one of helium (He), neon (Ne), argon (Ar), krypton (Kr) and xenon (Xe).
Preferably, the LiPF6The weight part ratio of the powder to the graphite material is 0.5-3: 8-16. LiPF6The weight portion ratio of the powder to the graphite material is 0.5:8, 0.5:10, 0.5:12, 0.5:16, 1:8, 1:10, 1:12, 2:15, 2:16, 3:8, 3:10, 3:11, 3:14, 3:15 and 3: 16.
Preferably, the graphite material comprises any one of natural spherical graphite, natural flake graphite, artificial graphite and mesocarbon microbeads.
Preferably, the solvent comprises a mixture of one or more of ethanol, acetone, ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, benzene, tetrahydrofuran. Preferably, the solvent is ethyl methyl carbonate.
Preferably, the temperature of the stirring centrifugation is 30-80 ℃, the stirring time is 30-120 min, and the stirring rotation speed is 1500-3500 r/min. Setting a certain temperature to make LiPF6The powder is easier to dissolve in the solvent, and the LiPF is improved6Solubility of the powder. Stirring time within the above rangeAnd within the rotation speed, the LiPF is adjusted6The powder is better dissolved in the solvent and better dispersed with the graphite material, but does not disturb the structure of the solute by stirring.
Preferably, the calcining temperature is 260-500 ℃, and the calcining time is 2-6 h. Because of LiPF6Decomposition reactions occur at temperatures above 260 ℃, as shown in the following equation:
LiPF6→LiF+PF5↑
according to the above reaction formula, LiPF6After decomposition, a LiF coating layer can be generated in situ, and compared with the LiF coated graphite directly, the LiPF6The in-situ coating method can ensure that the generated LiF layer is combined with graphite more tightly and the coating is more uniform. Organic impurities on the surface of the material such as methyl ethyl carbonate can be removed at high temperature; further LiPF6PF formed by decomposition reaction5The gas will be evacuated with the argon and collected by the respective device.
Preferably, the calcining and ball milling are carried out, the rotating speed is 150 r/min-500 r/min, and the ball milling time is 4-10 h. The rotating speeds are 150r/min, 160r/min, 170r/min, 180r/min, 200r/min, 220r/min, 250r/min, 270r/min, 300r/min, 350r/min, 380r/min, 420r/min, 450r/min, 480r/min and 500 r/min. The ball milling time is 4h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h, 8h, 8.5h, 9h, 9.5h and 10 h.
The second purpose of the invention is: aiming at the defects of the prior art, the cathode material is provided, the raw materials have good associativity, the material has higher lithium ion conductivity, the lithium ion de-intercalation rate on the graphite surface is effectively improved, the formed SEI film has high mechanical strength, is not easy to damage, and has good cycle performance and rate capability.
In order to achieve the purpose, the invention adopts the following technical scheme:
the negative electrode material is prepared by the preparation method of the negative electrode material.
The third purpose of the invention is that: aiming at the defects of the prior art, the negative plate is provided with the SEI film with high mechanical strength, good lithium ion conductivity and high de-intercalation rate.
In order to achieve the purpose, the invention adopts the following technical scheme:
the negative plate comprises a negative current collector and a negative active layer arranged on at least one surface of the negative current collector, wherein the negative active layer comprises the negative material.
The fourth purpose of the invention is that: aiming at the defects of the prior art, the lithium ion battery has good electrochemical performance, and the SEI film has high mechanical strength, good cycle performance and long service life.
In order to achieve the purpose, the invention adopts the following technical scheme:
a lithium ion battery is characterized by comprising the negative plate. Specifically, a lithium ion battery, includes positive plate, negative pole piece, diaphragm, electrolyte and casing, the diaphragm is used for separating positive plate with the negative pole piece, the casing is used for installing positive plate, negative pole piece, electrolyte and diaphragm.
Compared with the prior art, the invention has the beneficial effects that: preparation method of anode material, LiPF6The in-situ coating method can ensure that the generated LiF layer is combined with graphite more tightly, solve the problem of weak mechanical strength of the SEI film, improve the compatibility of the graphite and a negative electrode material, reduce the generation of the SEI film and improve the first charge-discharge efficiency of the electrode material; meanwhile, the graphite has high lithium ion conductivity, can improve the lithium ion de-intercalation rate on the graphite surface, and improves the cycle performance and the rate performance.
Detailed Description
1. A preparation method of a negative electrode material, which is prepared by mixing LiPF6And dissolving the powder and the graphite material in a solvent, stirring and mixing, stirring and centrifuging, and calcining to obtain the cathode material.
The invention adopts an in-situ coating mode and utilizes the LiPF with low price6And coating a layer of LiF on the surface of the prepared graphite material. The LiF coating layer can improve the compatibility of the graphite cathode material and the electrolyte; in addition, the LiF has high strength, and can keep the structure of the graphite cathode to be complete and not to be broken in the expansion and contraction process of the graphite cathodeAnd the cycle performance and the rate performance of the graphite cathode are improved.
The invention has simple operation and simple required equipment. LiPF6The in-situ coating method can ensure that the generated LiF layer is combined with graphite more tightly, improve the compatibility of the graphite and a negative electrode material, reduce the generation of an SEI (solid electrolyte interphase) film and improve the first charge-discharge efficiency of the electrode material; meanwhile, the graphite has higher lithium ion conductivity, and can improve the lithium ion de-intercalation rate on the graphite surface. The inert gas includes any one of helium (He), neon (Ne), argon (Ar), krypton (Kr) and xenon (Xe).
Preferably, the LiPF6The weight part ratio of the powder to the graphite material is 0.5-3: 8-16. LiPF6The weight portion ratio of the powder to the graphite material is 0.5:8, 0.5:10, 0.5:12, 0.5:16, 1:8, 1:10, 1:12, 2:15, 2:16, 3:8, 3:10, 3:11, 3:14, 3:15 and 3: 16.
Preferably, the graphite material comprises any one of natural spherical graphite, natural flake graphite, artificial graphite and mesocarbon microbeads.
Preferably, the solvent comprises a mixture of one or more of ethanol, acetone, ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, benzene, tetrahydrofuran. Preferably, the solvent is ethyl methyl carbonate.
Preferably, the temperature of the stirring centrifugation is 30-80 ℃, the stirring time is 30-120 min, and the stirring rotation speed is 1500-3500 r/min. Setting a certain temperature to make LiPF6The powder is easier to dissolve in the solvent, and the LiPF is improved6Solubility of the powder. In the above range of stirring time and rotation speed, LiPF is added6The powder is better dissolved in the solvent and better dispersed with the graphite material, but does not disturb the structure of the solute by stirring.
Preferably, the calcining temperature is 260-500 ℃, and the calcining time is 2-6 h. Because of LiPF6Decomposition reactions occur at temperatures above 260 ℃, as shown in the following equation:
LiPF6→LiF+PF5↑
according to the above reaction formula, LiPF6After decomposition, a LiF coating layer can be generated in situ, and compared with the LiF coated graphite directly, the LiPF6The in-situ coating method can ensure that the generated LiF layer is combined with graphite more tightly and the coating is more uniform. Organic impurities on the surface of the material such as methyl ethyl carbonate can be removed at high temperature; further LiPF6PF formed by decomposition reaction5The gas will be evacuated with the argon and collected by the respective device.
Preferably, the calcining and ball milling are carried out, the rotating speed is 150 r/min-500 r/min, and the ball milling time is 4-10 h.
2. The negative electrode material is prepared by the preparation method of the negative electrode material. The prepared cathode material has good binding property among raw materials, has high lithium ion conductivity, effectively improves the lithium ion de-intercalation rate on the graphite surface, and forms an SEI film with high mechanical strength, difficult damage, good cycle performance and rate capability.
3. The negative plate comprises a negative current collector and a negative active layer arranged on at least one surface of the negative current collector, wherein the negative active layer comprises the negative material. The negative plate provided by the invention has an SEI film with high mechanical strength, good lithium ion conductivity and high de-intercalation rate.
4. The lithium ion battery has good electrochemical performance, high SEI film mechanical strength, good cycle performance and long service life.
A lithium ion battery comprises the cathode. Specifically, a lithium ion battery, includes positive plate, negative pole piece, diaphragm, electrolyte and casing, the diaphragm is used for separating positive plate with the negative pole piece, the casing is used for installing positive plate, negative pole piece, electrolyte and diaphragm.
The active material layer coated on the current collector of the positive plate can be, but is not limited to, an active material of a chemical formula such as LiaNixCoyMzO2-bNb(wherein a is more than or equal to 0.95 and less than or equal to 1.2, x>0, y is not less than 0, z is not less than 0, and x + y + z is 1,0 is not less than b is not more than 1, M is selected from one or more of Mn and Al, and N is selected from one or more of F, P and S)One or more of the combination of compounds, the positive active material can also be, but is not limited to, LiCoO2、LiNiO2、LiVO2、LiCrO2、LiMn2O4、LiCoMnO4、Li2NiMn3O8、LiNi0.5Mn1.5O4、LiCoPO4、LiMnPO4、LiFePO4、LiNiPO4、LiCoFSO4、CuS2、FeS2、MoS2、NiS、TiS2And the like. The positive electrode active material may be further modified, and the method of modifying the positive electrode active material is known to those skilled in the art, for example, the positive electrode active material may be modified by coating, doping, and the like, and the material used in the modification may be one or a combination of more of Al, B, P, Zr, Si, Ti, Ge, Sn, Mg, Ce, W, and the like. And the positive electrode current collector is generally a structure or a part for collecting current, and the positive electrode current collector may be any material suitable for being used as a positive electrode current collector of a lithium ion battery in the field, for example, the positive electrode current collector may include, but is not limited to, a metal foil and the like, and more specifically, may include, but is not limited to, an aluminum foil and the like.
Preparing a negative plate: the negative electrode material, a conductive agent super-p and a binder SBR are fully ground according to the mass ratio of 80:10:10 (the total mass is 0.3g), then 0.55mL of deionized water is added to be ground into slurry, the slurry is uniformly coated on an aluminum foil to form a pole piece, and the pole piece is placed in a vacuum drying oven at 70 ℃ to be baked for 12 hours. Rolling and punching to obtain the required size of the current-clamping positive plate.
And the separator may be various materials suitable for lithium ion battery separators in the art, and for example, may be one or a combination of more of polyethylene, polypropylene, polyvinylidene fluoride, aramid, polyethylene terephthalate, polytetrafluoroethylene, polyacrylonitrile, polyimide, polyamide, polyester, natural fiber, and the like, including but not limited thereto.
The lithium ion battery also comprises electrolyte, wherein the electrolyte comprises organic solvent and electrolyte lithiumSalts and additives. Wherein the electrolyte lithium salt may be LiPF used in a high-temperature electrolyte6And/or LiBOB; or LiBF used in low-temperature electrolyte4、LiBOB、LiPF6At least one of; or LiBF used in anti-overcharge electrolyte4、LiBOB、LiPF6At least one of, LiTFSI; may also be LiClO4、LiAsF6、LiCF3SO3、LiN(CF3SO2)2At least one of (1). And the organic solvent may be a cyclic carbonate including PC, EC; or chain carbonates including DFC, DMC, or EMC; and also carboxylic acid esters including MF, MA, EA, MP, etc. And additives include, but are not limited to, film forming additives, conductive additives, flame retardant additives, overcharge prevention additives, control of H in the electrolyte2At least one of additives of O and HF content, additives for improving low temperature performance, and multifunctional additives.
Wherein the shell is made of an aluminum plastic film or a stainless steel plate. Preferably, the housing is an aluminum plastic film.
Manufacturing a CR2025 button cell:
a button cell is assembled by taking a lithium metal sheet as a counter electrode, common electrolyte of lithium ion battery materials and a diaphragm with ceramic coatings coated on two sides in a glove box filled with argon.
The present invention will be described in further detail below with reference to specific embodiments and comparative examples, but the embodiments of the present invention are not limited thereto.
Example 1
Under argon atmosphere, 10g of graphite anode material and 0.608g of LiPF are weighed by an electronic balance6Placing the mixture into a beaker, adding 100mL of methyl ethyl carbonate into the beaker, and continuously stirring the mixture to uniformly mix the mixture; magnetically stirring at 50 deg.C for 100 min; carrying out centrifugal treatment on the mixed solution in the step at 2000r/min, placing the lower-layer precipitate in a vacuum tube furnace, and calcining for 4 hours at 350 ℃ in an argon atmosphere; and finally, ball-milling for 6 hours at 300r/min by adopting a high-energy ball milling method, and sieving by using a 250-mesh sieve to obtain the graphite cathode material coated with 1 wt% of LiF.
Example 2
Under argon atmosphere, 12g of graphite anode material and 0.8g of LiPF are weighed by an electronic balance6Placing the mixture into a beaker, adding 100mL of methyl ethyl carbonate into the beaker, and continuously stirring the mixture to uniformly mix the mixture; magnetically stirring at 60 deg.C for 80 min; carrying out centrifugal treatment on the mixed solution in the step at 1800r/min, placing the lower-layer precipitate in a vacuum tube furnace, and calcining for 5 hours at 400 ℃ in an argon atmosphere; and finally, ball-milling for 7 hours at 350r/min by adopting a high-energy ball milling method, and sieving by using a 250-mesh sieve to obtain the graphite cathode material coated with 1 wt% of LiF.
Example 3
Under argon atmosphere, 8g of graphite negative electrode material and 1.5g of LiPF are weighed by an electronic balance6Placing the mixture into a beaker, adding 100mL of methyl ethyl carbonate into the beaker, and continuously stirring the mixture to uniformly mix the mixture; magnetically stirring at 55 deg.C for 50 min; carrying out centrifugal treatment on the mixed solution in the step at 1500r/min, placing the lower-layer precipitate in a vacuum tube furnace, and calcining for 6 hours at 280 ℃ in an argon atmosphere; and finally, ball-milling for 10 hours at 450r/min by adopting a high-energy ball milling method, and sieving by using a 250-mesh sieve to obtain the graphite cathode material coated with 1 wt% LiF.
Example 4
Under argon atmosphere, 16g of graphite negative electrode material and 0.5g of LiPF are weighed by an electronic balance6Placing the mixture into a beaker, adding 100mL of methyl ethyl carbonate into the beaker, and continuously stirring the mixture to uniformly mix the mixture; magnetically stirring at 60 deg.C for 110 min; centrifuging the mixed solution in the step at 3000r/min, placing the lower-layer precipitate in a vacuum tube furnace, and calcining for 2 hours at 500 ℃ in an argon atmosphere; and finally, ball-milling for 7 hours at 400r/min by adopting a high-energy ball milling method, and sieving by using a 250-mesh sieve to obtain the graphite cathode material coated with 1 wt% of LiF.
Example 5
Under argon atmosphere, 15g of graphite negative electrode material and 2.5g of LiPF are weighed by an electronic balance6Placing the mixture into a beaker, adding 100mL of methyl ethyl carbonate into the beaker, and continuously stirring the mixture to uniformly mix the mixture; magnetically stirring at 50 deg.C for 90 min; centrifuging the mixed solution in the step at 3500r/min,placing the lower layer precipitate in a vacuum tube furnace, and calcining for 2h at 500 ℃ in an argon atmosphere; and finally, ball-milling for 4 hours at 260r/min by adopting a high-energy ball milling method, and sieving by using a 250-mesh sieve to obtain the graphite cathode material coated with 1 wt% of LiF.
Example 6
The difference from example 1 is that: the LiPF6The weight part ratio of the powder to the graphite material is 1.5: 13.
The rest is the same as embodiment 1, and the description is omitted here.
Example 7
The difference from example 1 is that: the LiPF6The weight portion ratio of the powder to the graphite material is 1.2: 11.
The rest is the same as embodiment 1, and the description is omitted here.
Example 8
The difference from example 1 is that: the LiPF6The weight portion ratio of the powder to the graphite material is 2.7: 8.
The rest is the same as embodiment 1, and the description is omitted here.
Example 9
The difference from example 1 is that: the LiPF6The weight portion ratio of the powder to the graphite material is 0.8: 9.
The rest is the same as embodiment 1, and the description is omitted here.
Example 10
The difference from example 1 is that: the LiPF6The weight portion ratio of the powder to the graphite material is 2.5: 12.
The rest is the same as embodiment 1, and the description is omitted here.
Comparative example 1
The difference from example 1 is that: and directly calcining 10g of graphite cathode material in an inert gas environment to obtain the cathode material.
The rest is the same as embodiment 1, and the description is omitted.
And (3) performance testing: the negative electrode materials prepared in examples 1 to 10 and comparative example 1 and the lithium ion battery prepared from the negative electrode material were subjected to performance tests, and the test results are recorded in table 1.
And (3) testing the cycle performance: the lithium ion secondary battery was charged at 25 ℃ to 4.45V at a constant current of 1C (1C: 354mA/g), then charged at a constant voltage of 4.45V to a current of 0.05C, left to stand for 5min, and then discharged at a constant current of 1C to 2.0V, which is a charge-discharge cycle course, and the discharge capacity of this time was the discharge capacity of the first cycle. The lithium ion secondary battery was subjected to 400-cycle charge/discharge tests in accordance with the above-described method, and the discharge capacity per one cycle was recorded. The cycle capacity retention (%) was 400 cycles of discharge capacity/first cycle of discharge capacity × 100%.
And (3) testing the safety performance of the through nail: the lithium ion battery is fully charged, then high-temperature-resistant steel needles (the taper angle of a needle point is 45-60 degrees, the surface of the steel needle is smooth and clean, rust-free, oxidation layer-free and oil-free) with the diameter phi of 1mm and the diameter phi of 3mm are respectively used for penetrating the lithium ion battery from the direction perpendicular to the polar plate of the lithium ion battery at the speed of (25 +/-5) mm/s, the penetrating position is close to the geometric center of the surface of the punctured polar plate, the steel needle stays in the lithium ion battery, and the lithium ion battery passes a nail penetration test after 1h observation without ignition and explosion.
TABLE 1
As can be seen from table 1, the negative electrode material prepared by the present invention has better capacity retention rate and better mechanical strength compared with the prior art, and does not ignite or explode when subjected to a needle penetration test. Compared with examples 1-5 and comparative example 1, the preparation method of the negative electrode material disclosed by the invention has the advantages that the capacity retention rate of the first charge and discharge, the capacity retention rate after 400 charge and discharge cycles and the mechanical property are effectively improved, the capacity retention rate of the first charge and discharge reaches 97.6%, the capacity retention rate after 400 charge and discharge cycles still keeps 86.8%, and the negative electrode material does not ignite and explode when subjected to a needle penetration test. From the comparison of examples 1, 6-10, when the LiPF is set6When the weight part ratio of the powder to the graphite material is 0.608:10, the prepared negative electrode material has better performance because the lithium fluoride generated in situ is just uniformThe graphite material is completely coated, the coating rate is high, and the thickness does not influence the extraction of lithium ions, so that the capacity retention rate is improved.
Variations and modifications to the above-described embodiments may also occur to those skilled in the art, which fall within the scope of the invention as disclosed and taught herein. Therefore, the present invention is not limited to the above-mentioned embodiments, and any obvious improvement, replacement or modification made by those skilled in the art based on the present invention is within the protection scope of the present invention. Furthermore, although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
Claims (10)
1. The preparation method of the anode material is characterized in that LiPF is added in an inert gas environment6And dissolving the powder and the graphite material in a solvent, stirring and mixing, stirring and centrifuging, and calcining in an inert gas environment to obtain the cathode material.
2. The method for producing the anode material according to claim 1, wherein the LiPF is6The weight part ratio of the powder to the graphite material is 0.5-3: 8-16.
3. The method for preparing the negative electrode material of claim 1, wherein the graphite material comprises any one of natural spherical graphite, natural flake graphite, artificial graphite, and mesocarbon microbeads.
4. The method according to claim 1, wherein the solvent comprises a mixture of one or more of ethanol, acetone, ethyl methyl carbonate, dimethyl carbonate, diethyl carbonate, benzene, and tetrahydrofuran.
5. The preparation method of the anode material according to claim 1 or 2, wherein the temperature of the stirring centrifugation is 30-80 ℃, the stirring time is 30-120 min, and the stirring rotation speed is 1500-3500 r/min.
6. The preparation method of the anode material according to claim 1 or 2, wherein the calcination temperature is 260-500 ℃ and the calcination time is 2-6 h.
7. The preparation method of the anode material according to claim 1 or 2, wherein the calcining is followed by ball milling at a rotation speed of 150r/min to 500r/min for 4 to 10 hours.
8. A negative electrode material characterized by being produced by the method for producing a negative electrode material according to any one of claims 1 to 7.
9. A negative electrode sheet comprising a negative electrode current collector and a negative electrode active layer provided on at least one surface of the negative electrode current collector, wherein the negative electrode active layer comprises the negative electrode material according to claim 8.
10. A lithium ion battery comprising the negative electrode sheet according to claim 9.
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| CN202111423313.4A CN114212785A (en) | 2021-11-26 | 2021-11-26 | Negative electrode material and preparation method thereof, negative plate and lithium ion battery |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103633288A (en) * | 2012-08-28 | 2014-03-12 | 华为技术有限公司 | Lithium ion battery composite negative electrode material and preparation method thereof, lithium ion battery negative electrode sheet and lithium ion battery |
| CN110797530A (en) * | 2019-09-26 | 2020-02-14 | 惠州锂威新能源科技有限公司 | High-voltage lithium cobalt oxide graphite battery and preparation method thereof |
| CN113659147A (en) * | 2021-08-16 | 2021-11-16 | 成都初肆柒叁科技有限公司 | Optimized preparation method of prefabricated SEI film on surface of negative electrode of zinc ion lithium battery |
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103633288A (en) * | 2012-08-28 | 2014-03-12 | 华为技术有限公司 | Lithium ion battery composite negative electrode material and preparation method thereof, lithium ion battery negative electrode sheet and lithium ion battery |
| CN110797530A (en) * | 2019-09-26 | 2020-02-14 | 惠州锂威新能源科技有限公司 | High-voltage lithium cobalt oxide graphite battery and preparation method thereof |
| CN113659147A (en) * | 2021-08-16 | 2021-11-16 | 成都初肆柒叁科技有限公司 | Optimized preparation method of prefabricated SEI film on surface of negative electrode of zinc ion lithium battery |
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