CN113851627A - Porous silicon-carbon negative electrode material and preparation method thereof - Google Patents
Porous silicon-carbon negative electrode material and preparation method thereof Download PDFInfo
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Abstract
The invention provides a porous silicon-carbon composite negative electrode material for a lithium ion battery and a preparation method thereof. The negative electrode material has a structure of 'silicon-carbon composite inner core + pore + amorphous carbon coating'. In the process of preparing the cathode material, several carbon sources with different properties are adopted for staged compounding, and the purpose of forming pores with certain sizes in the material is achieved by controlling the temperature during heat treatment. Compared with the prior art, the porous silicon-carbon composite negative electrode material provided by the invention well solves the problem of low cycle performance caused by volume expansion of the traditional silicon-based negative electrode, and meanwhile, because the compact amorphous carbon coating layer has a smaller specific surface area, the first coulombic efficiency is as high as 86.1%, the reversible specific capacity is 1517.1mAh/g, and the capacity is kept above 85% after 50 times of cycle.
Description
Technical Field
The invention relates to the field of lithium ion battery cathode materials, in particular to an application of a silicon-carbon cathode material in a lithium ion battery.
Background
The commercial lithium ion battery mainly adopts graphite carbon materials as negative active materials. However, the carbon-based negative electrode material cannot meet the requirements of miniaturization of electronic devices and high power and high capacity of lithium ion batteries for vehicles due to the low specific capacity (372mAh/g) and the safety problem caused by lithium deposition, and therefore, a novel negative electrode material for lithium ion batteries, which can replace carbon materials, has high energy density, high safety performance and long cycle life, needs to be developed.
Silicon, as a novel lithium ion battery negative electrode material, has been the focus of attention of researchers due to its high theoretical specific capacity (4200 mAh/g). But its volume expansion during charge and discharge causes active particles to be pulverized, and then the capacity is rapidly attenuated due to loss of electrical contact. To solve this problem, much research has been conducted. At present, nano silicon particles are mainly used for silicon/carbon compounding, such as chinese patent CN101339987A, chinese patent CN1402366A and chinese patent CN 1767234A. Most of the prepared silicon-carbon negative electrode materials are simple combination of nano silicon and porous carbon, no in-situ buffer group is generated in the process of lithium intercalation and deintercalation for the first time, and meanwhile, no vacancy capable of accommodating volume change of the lithium intercalation and deintercalation is reserved, so that the volume effect in the charge and discharge process cannot be fundamentally inhibited, the capacity can still be rapidly attenuated along with the increase of cycle times, and the preparation of the negative electrode materials with the porous structure becomes a mainstream, such as Chinese patents CN103779544A, CN105098183A, CN108199030A and the like.
CN103779544A discloses a preparation method of a porous silicon/carbon composite material, which comprises the following steps: and performing ball milling and mixing on decomposable silicide and a carbon source, performing heat treatment, treating a product after the heat treatment in mixed acid of hydrochloric acid and hydrofluoric acid, centrifuging, and drying to obtain the porous silicon/carbon composite material.
CN105098183A discloses a method for preparing lithium ion battery cathode material by using rice hull as raw material, which is characterized in that natural rice hull is used as raw material to react with Na2CO3Calcining at 850-1000 ℃ in the nitrogen atmosphere to obtain the silicon-containing microporous carbon cathode material. Although the material has good stability, the capacity is low, and the material cannot meet the practical application.
CN108199030A discloses a preparation method of a porous silicon/graphite/carbon composite negative electrode material of a lithium ion secondary battery, wherein a silicon source of the composite material is natural ore soil, a metal simple substance or alloy powder and anhydrous metal chloride are utilized to reduce the natural ore soil into simple substance silicon under a mild condition, and the reduced porous silicon, graphite and an organic carbon source are subjected to high-energy ball milling and mixing. The natural ore soil has inherent pore characteristics, the volume expansion can be effectively relieved, and the prepared composite material has higher charge and discharge capacity and stability, but the process is complex and the production is difficult.
In summary, in the prior art, the porous silicon carbon anode material is prepared by methods such as nano silicon alloy etching, porous framework deposition, silicon oxide reduction and the like, but byproducts which are not favorable for the performance of the battery are easily generated or the process is complex. Therefore, the technical problem in the field is to develop a preparation method of a lithium ion battery cathode material with high first charge-discharge efficiency, low volume expansion effect and high charge-discharge cycle stability.
Disclosure of Invention
The purpose of the invention is: provides a lithium ion battery cathode material with high first efficiency, low volume expansion effect and high charge-discharge cycle stability.
The technical scheme is as follows:
a porous silicon carbon negative electrode material comprises a core-shell structure, wherein a core is a carbon silicon negative electrode material, and porous gaps are distributed in the core; the shell comprises a two-layer structure, wherein the inner layer is a conductive material layer, and the outer layer is a carbon coating layer.
The diameter range of the porous gaps in the inner core is 50nm-5 mu m, the porosity range of the inner core is 5-30%, and the section shapes of the porous gaps comprise one or more of spherical, spheroidal, strip-shaped and other irregular holes; the size of the inner core is 1-20 um.
The conductive material layer comprises one or a mixture of a plurality of graphite sheets, graphene, carbon nanotubes and the like; the thickness of the conductive material layer is 10-100 nm.
The thickness of the carbon coating layer is 50nm-200 nm.
The specific surface area of the porous silicon-carbon negative electrode material is 1-3m2(ii) g, tap density of 0.6-1.5g/cm3。
The porous silicon-carbon negative electrode material has the silicon content of 10-60% and the carbon content of 40-90%.
The preparation method of the porous silicon-carbon negative electrode material comprises the following steps:
step 1, ball-milling and mixing a nano-silicon raw material and a first carbon source, and performing heat treatment to obtain a first precursor;
step 2, mixing the first precursor with a second carbon source, and carrying out heat treatment to obtain a second precursor;
and 3, mixing the second precursor with a third carbon source, and carrying out heat treatment to obtain the porous silicon-carbon anode material.
The mass ratio of the nano silicon raw material: a first carbon source: a second carbon source is 10:10: 5; mass ratio of the second precursor: third carbon source 1: 0.05-0.5.
In the step 1, the first carbon source is selected from saccharides having a molecular weight of 2000 or less; preferably one or more of sucrose, glucose, xylose, starch sugar, maltose or fructose; and (3) heat treatment parameters: the temperature is 600-1000 ℃, and the time is 1-12 hours; the rotation speed of the ball mill is 500 plus 800rpm, and the ball milling time is more than 1 h; the median diameter of the nano silicon is 20-150 nm.
In the step 2, the second carbon source is one or a mixture of several of graphite flakes, graphene, carbon nanotubes and the like; preferably, the second carbon source is formed by mixing graphite sheets and carbon nanotubes, and the mass ratio of the graphite sheets to the carbon nanotubes is 1: 0.3 to 4; and (3) heat treatment parameters: the temperature is 800 ℃ and 1400 ℃, and the heat treatment and heat preservation time is 1-10 hours.
In the step 3, the third carbon source is at least one of polyacrylonitrile, polypyrrole, polyvinyl chloride, polyvinylidene fluoride, polyvinyl alcohol, polystyrene, phenolic resin, furfural resin, epoxy resin, coal tar pitch, petroleum pitch, cellulose, aromatic hydrocarbon or aromatic lipid;
in the heat treatment in any of the steps 1 to 3, the protective atmosphere is required to be selected from argon, helium and the like.
A lithium ion battery comprises a battery shell, a battery core arranged in the battery shell and electrolyte filled in the battery shell; the battery cell comprises a positive pole piece, a diaphragm and a negative pole piece which are sequentially arranged; the negative pole piece comprises a negative pole current collector and a negative pole material positioned on the negative pole current collector, wherein the negative pole material comprises the silicon-carbon composite material as defined in claim 1. The negative electrode is made of the porous silicon-carbon composite negative electrode material. The battery has the characteristics of high first charge-discharge efficiency, low volume expansion rate, strong cycle stability and the like, the first coulombic efficiency is as high as 86.1%, the reversible specific capacity is 1517.1mAh/g, and the capacity is kept above 85% after 50 times of circulation.
Advantageous effects
The invention adopts three carbon sources to prepare the silicon-carbon cathode material, and the selection of the carbon source types is based on:
the first carbon source is hydrocarbon which is easy to carbonize, such as sucrose, glucose, xylose and the like, on one hand, the carbon source is easy to be bonded with nano silicon to form a compound, on the other hand, when the carbon source is carbonized in protective gas, the precursor compound forms a porous structure by removing H and O, and impurities except carbon and silicon are not generated; carbon contained in a precursor prepared from a first carbon source mainly exists in an amorphous carbon form, and the carbon provides a good conductive environment for a material core and plays a role in connecting an integral composite structure formed in the next preparation step; the generated porous structure is beneficial to forming the porous structure, plays a role in buffering the silicon material in the contraction and expansion process, and improves the cycle performance of the battery.
The second carbon source is made of carbon allotrope materials with specific structures, such as graphite flakes, graphene, carbon nanotubes and the like, and can form a certain gap after being mixed with the first precursor, so that the finally prepared material is less influenced by expansion after lithium intercalation; while the second carbon source can provide a better conductive environment.
The third carbon source is carbon-containing organic matter which is viscous at normal temperature or after being heated, such as asphalt, phenolic resin, epoxy resin and the like, on one hand, the carbon-containing organic matter has fluidity after being heated and can be uniformly coated on the surface of the silicon-carbon precursor, and on the other hand, a stable amorphous carbon coating layer is easy to form.
Drawings
FIG. 1 is a sectional SEM topography of a sample obtained in example 1;
FIG. 2 is a sectional SEM topography of a sample obtained in comparative example 3.
Detailed Description
Example 1
The preparation method comprises the following steps: (1) ball-milling and mixing nano silicon (D50-100 nm) and sucrose in a nitrogen environment, wherein the mass ratio of the nano silicon to the sucrose is 1:1, the rotating speed of a ball mill is 500rpm, and the mixture with uniform components is obtained after ball milling for 12 hours; (2) placing the mixture in a nitrogen environment, heating to 800 ℃ at a heating speed of 5 ℃/min, preserving heat for 3 hours, naturally cooling in a furnace, and crushing and grinding a product to obtain the nano silicon/carbon composite material after cooling to room temperature; (3) uniformly mixing the nano silicon/carbon composite material, the asphalt and the nano graphite sheet carbon nano tube, wherein the mass ratio of the nano silicon/carbon composite material to the asphalt to the graphite sheet to the carbon nano tube is 1.4:0.5:0.3: 0.2; (4) placing the mixture in a nitrogen environment, slowly heating to 1100 ℃ at the heating rate of 1 ℃/min, keeping for 3 hours, naturally cooling to room temperature in a furnace, and crushing and grinding to obtain a silicon-carbon composite material precursor; (5) uniformly mixing the composite material and asphalt in a mass ratio of 1: 0.15; (6) and heating the mixture to 850 ℃ at the heating rate of 10 ℃/min, preserving the temperature until the asphalt is completely carbonized, naturally cooling, and crushing and grinding to obtain the porous silicon-carbon composite negative electrode material.
Fig. 1 is an SEM topography of a sample obtained in example 1, wherein a dark color portion in a cross section of an inner core is a composite formed by a second carbon source such as a graphite sheet, a carbon nanotube, and the like and a precursor 1, and it is observed that a fractal structure with a certain dimension is formed after the composite is enlarged.
Example 2
The preparation method comprises the following steps: (1) ball-milling and mixing nano silicon (D50-100 nm) and glucose in a nitrogen environment, wherein the mass ratio of the nano silicon to the glucose is 1:1, the rotating speed of a ball mill is 500rpm, and the mixture with uniform components is obtained after ball milling for 12 hours; (2) placing the mixture in a nitrogen environment, heating to 800 ℃ at a heating speed of 5 ℃/min, preserving heat for 3 hours, naturally cooling in a furnace, and crushing and grinding a product to obtain the nano silicon/carbon composite material after cooling to room temperature; (3) uniformly mixing the nano silicon/carbon composite material, the asphalt and the nano graphite sheet carbon nano tube, wherein the mass ratio of the nano silicon/carbon composite material to the asphalt to the graphite sheet to the carbon nano tube is 1.4:0.5:0.3: 0.2; (4) placing the mixture in a nitrogen environment, slowly heating to 1100 ℃ at the heating rate of 1 ℃/min, keeping for 3 hours, naturally cooling to room temperature in a furnace, and crushing and grinding to obtain a silicon-carbon composite material precursor; (5) uniformly mixing the composite material and asphalt in a mass ratio of 1: 0.15; (6) and heating the mixture to 850 ℃ at the heating rate of 10 ℃/min, preserving the temperature until the asphalt is completely carbonized, naturally cooling, and crushing and grinding to obtain the porous silicon-carbon composite negative electrode material.
Example 3
The preparation method comprises the following steps: (1) ball-milling and mixing nano silicon (D50-100 nm) and xylose in a nitrogen environment, wherein the mass ratio of the nano silicon to the xylose is 1:1, the rotating speed of a ball mill is 500rpm, and the mixture with uniform components is obtained after ball milling for 12 hours; (2) placing the mixture in a nitrogen environment, heating to 800 ℃ at a heating speed of 5 ℃/min, preserving heat for 3 hours, naturally cooling in a furnace, and crushing and grinding a product to obtain the nano silicon/carbon composite material after cooling to room temperature; (3) uniformly mixing the nano silicon/carbon composite material, the asphalt and the nano graphite sheet carbon nano tube, wherein the mass ratio of the nano silicon/carbon composite material to the asphalt to the graphite sheet to the carbon nano tube is 1.4:0.5:0.3: 0.2; (4) placing the mixture in a nitrogen environment, slowly heating to 1100 ℃ at the heating rate of 1 ℃/min, keeping for 3 hours, naturally cooling to room temperature in a furnace, and crushing and grinding to obtain a silicon-carbon composite material precursor; (5) uniformly mixing the composite material and asphalt in a mass ratio of 1: 0.15; (6) and heating the mixture to 850 ℃ at the heating rate of 10 ℃/min, preserving the temperature until the asphalt is completely carbonized, naturally cooling, and crushing and grinding to obtain the porous silicon-carbon composite negative electrode material.
Comparative example 1
Comparative example 1 the first and second carbon source components in example 1 were exchanged.
The preparation method comprises the following steps: (1) ball-milling and mixing nano silicon (D50-100 nm) and asphalt in a nitrogen environment, wherein the mass ratio of the nano silicon to the asphalt is 1:1, the rotating speed of a ball mill is 500rpm, and the mixture with uniform components is obtained after ball milling for 12 hours; (2) placing the mixture in a nitrogen environment, heating to 800 ℃ at a heating speed of 5 ℃/min, preserving heat for 3 hours, naturally cooling in a furnace, and crushing and grinding a product to obtain the nano silicon/carbon composite material after cooling to room temperature; (3) uniformly mixing the nano silicon/carbon composite material, cane sugar and the nano graphite sheet carbon nano tube, wherein the mass ratio of the nano silicon/carbon composite material to the asphalt to the graphite sheet to the carbon nano tube is 1.4:0.5:0.3: 0.2; (4) placing the mixture in a nitrogen environment, slowly heating to 1100 ℃ at the heating rate of 1 ℃/min, keeping for 3 hours, naturally cooling to room temperature in a furnace, and crushing and grinding to obtain a silicon-carbon composite material precursor; (5) uniformly mixing the composite material and asphalt in a mass ratio of 1: 0.15; (6) and heating the mixture to 850 ℃ at the heating rate of 10 ℃/min, preserving the temperature until the asphalt is completely carbonized, naturally cooling, and crushing and grinding to obtain the porous silicon-carbon composite negative electrode material.
Comparative example 2
The difference from example 1 is that: the second carbon source is replaced by the first carbon source.
The preparation method comprises the following steps: (1) ball-milling and mixing nano silicon (D50-100 nm) and sucrose in a nitrogen environment, wherein the mass ratio of the nano silicon to the sucrose is 1:1, the rotating speed of a ball mill is 500rpm, and the mixture with uniform components is obtained after ball milling for 12 hours; (2) placing the mixture in a nitrogen environment, heating to 800 ℃ at a heating speed of 5 ℃/min, preserving heat for 3 hours, naturally cooling in a furnace, and crushing and grinding a product to obtain the nano silicon/carbon composite material after cooling to room temperature; (3) uniformly mixing the nano silicon/carbon composite material, cane sugar and the nano graphite sheet carbon nano tube, wherein the mass ratio of the nano silicon/carbon composite material to the asphalt to the graphite sheet to the carbon nano tube is 1.4:0.5:0.3: 0.2; (4) placing the mixture in a nitrogen environment, slowly heating to 1100 ℃ at the heating rate of 1 ℃/min, keeping for 3 hours, naturally cooling to room temperature in a furnace, and crushing and grinding to obtain a silicon-carbon composite material precursor; (5) uniformly mixing the composite material and asphalt in a mass ratio of 1: 0.15; (6) and heating the mixture to 850 ℃ at the heating rate of 10 ℃/min, preserving the temperature until the asphalt is completely carbonized, naturally cooling, and crushing and grinding to obtain the porous silicon-carbon composite negative electrode material.
Comparative example 3
The difference from example 1 is that: and directly compounding the silicon nanoparticles and a second carbon source material without preparing a first precursor, and then carrying out carbon coating.
The preparation method comprises the following steps: (1) uniformly mixing nano silicon, nano graphite sheets and carbon nano tubes, wherein the mass ratio of the nano silicon to the asphalt to the graphite sheets to the carbon nano tubes is 1:0.5:0.3: 0.2; (2) placing the mixture in a nitrogen environment, slowly heating to 1100 ℃ at the heating rate of 1 ℃/min, keeping for 3 hours, naturally cooling to room temperature in a furnace, and crushing and grinding to obtain a silicon-carbon composite material precursor; (3) uniformly mixing the composite material and asphalt in a mass ratio of 1: 0.15; (4) and heating the mixture to 850 ℃ at the heating rate of 10 ℃/min, preserving the temperature until the asphalt is completely carbonized, naturally cooling, and crushing and grinding to obtain the porous silicon-carbon composite negative electrode material.
Battery preparation and test flow
The electrochemical performance of the nitrogen-doped silicon-carbon composite negative electrode material was evaluated by assembling the material into a CR 2032-button half cell. The button cell manufacturing process comprises the following steps: the mass ratio of the active material (S i/C), the acetylene black, the CMC and the SBR is 80: 10: 4: 6, wherein the CMC is a 1% aqueous solution. The slurry was dispersed with a high shear mixer (Fluko FA25, Germany) at 10000rpm for 30 min. The homogenized slurry was then uniformly coated on a copper foil 15 μm thick. Naturally drying, placing the copper foil in a vacuum drying oven at 80 ℃ for 10 hours, and compacting the dried copper foil by using a roller press; and punching the pole piece and cutting the pole piece into a circular piece with the diameter of 13 mm. Assembling a half cell in a glove box protected by high-purity argon, wherein a counter electrode sheet adopts metal lithium foil, a diaphragm adopts a polypropylene porous membrane, and 1M LiPF6 is prepared by mixing ethylene carbonate/dimethyl carbonate/methyl ethyl carbonate according to a volume ratio of 1: 1:1 as an electrolyte, 1M LiPF6 and 5 wt% fluoroethylene carbonate were added to the mixed solution obtained in 1. The battery charging and discharging test is carried out in a multi-channel battery, and the test voltage range of the silicon-carbon material is 0.01V-1.5V (vs. Li +/Li).
After the electrode materials prepared in the above examples and comparative examples are manufactured into batteries, the main electrochemical test results are summarized as follows:
TABLE 1
As can be seen from the above experimental results,
it can be seen from the comparison between the embodiment 1 and the comparative example 1 that the easily carbonized material used in the first carbon source can better form a porous structure with the silicon nanomaterial in the process of compounding, thereby playing a buffering role in the contraction and expansion process of the silicon material and improving the cycle performance of the battery; as can be seen from the comparison between the embodiment 1 and the comparative example 2, after the second carbon source is added, the conductive material effectively improves the conductive property of the battery material and improves the rate capability of the battery material; as can be seen by comparing example 1 with comparative example 3, the first carbon source plays a key role in the inner core, and the cycle performance of the material is improved by the buffering effect of the first carbon source; the difficulty of forming a porous structure is well reduced by correctly selecting carbon sources with different properties by stages; compared with a non-porous material, the pores formed in the inner core of the material well solve the problem of low cycle efficiency of the carbon-silicon cathode material; compared with the traditional graphite material, the negative electrode prepared from the material provided by the invention also has higher specific capacity, energy density and first charge-discharge efficiency, and the expansion rate is closer to that of graphite.
Claims (10)
1. A porous silicon carbon negative electrode material comprises a core-shell structure and is characterized in that a core is made of a carbon silicon negative electrode material, and porous gaps are distributed in the core;
the shell comprises a two-layer structure, wherein the inner layer is a conductive material layer, and the outer layer is a carbon coating layer.
2. The porous silicon carbon anode material of claim 1, wherein the diameter of the porous voids in the inner core is in the range of 50nm to 5 μm, the porosity in the inner core is in the range of 5 to 30%, and the cross-sectional shape of the porous voids comprises one or more of spherical, spheroidal, and elongated irregular pores; the size of the inner core is 1-20 um.
3. The porous silicon carbon negative electrode material as claimed in claim 1, wherein the conductive material layer comprises one or more of graphite sheet, graphene, carbon nanotube, etc.; the thickness of the conductive material layer is 10-100 nm.
4. The porous silicon carbon anode material of claim 1, wherein the carbon coating layer has a thickness of 50nm to 200 nm;
the specific surface area of the porous silicon-carbon negative electrode material is 1-3m2(ii) g, tap density of 0.6-1.5g/cm3；
The porous silicon-carbon negative electrode material has the silicon content of 10-60% and the carbon content of 40-90%.
5. The preparation method of the porous silicon carbon anode material according to claim 1, characterized by comprising the following steps:
step 1, ball-milling and mixing a nano-silicon raw material and a first carbon source, and performing heat treatment to obtain a first precursor;
step 2, mixing the first precursor with a second carbon source, and carrying out heat treatment to obtain a second precursor;
and 3, mixing the second precursor with a third carbon source, and carrying out heat treatment to obtain the porous silicon-carbon anode material.
6. The preparation method of the porous silicon-carbon anode material as claimed in claim 5, wherein the mass ratio of the nano-silicon raw material: a first carbon source: a second carbon source is 10:10: 5; the mass ratio of the second precursor to the third carbon source is 1: 0.05-0.5.
7. The method for preparing the porous silicon-carbon anode material according to claim 5, wherein in the step 1, the first carbon source is selected from saccharides with molecular weights below 2000, preferably one or a mixture of sucrose, glucose, xylose, starch sugar, maltose, fructose and the like; and (3) heat treatment parameters: the temperature is 600-1000 ℃, and the time is 1-12 hours; the rotation speed of the ball mill is 500 plus 800rpm, and the ball milling time is more than 1 h; the median diameter of the nano silicon is 20-150 nm.
8. The method for preparing the porous silicon-carbon anode material according to claim 5, wherein in the step 2, the second carbon source is one or a mixture of graphite sheets, graphene, carbon nanotubes and the like; preferably, the second carbon source is formed by mixing graphite sheets and carbon nanotubes, and the mass ratio of the graphite sheets to the carbon nanotubes is 1: 0.3 to 4; and (3) heat treatment parameters: the temperature is 800 ℃ and 1400 ℃, and the heat treatment and heat preservation time is 1-10 hours.
9. The method for preparing the porous silicon-carbon negative electrode material according to claim 5, wherein in the step 3, the third carbon source is at least one of polyacrylonitrile, polypyrrole, polyvinyl chloride, polyvinylidene fluoride, polyvinyl alcohol, polystyrene, phenolic resin, furfural resin, epoxy resin, coal tar pitch, petroleum pitch, cellulose, aromatic hydrocarbon or aromatic lipid; in the heat treatment in any one of the steps 1 to 3, the protective atmosphere is required to be selected from argon, helium and the like.
10. A lithium ion battery comprises a battery shell, a battery core arranged in the battery shell and electrolyte filled in the battery shell; the battery cell comprises a positive pole piece, a diaphragm and a negative pole piece which are sequentially arranged; the negative pole piece comprises a negative pole current collector and a negative pole material positioned on the negative pole current collector, wherein the negative pole material comprises the silicon-carbon composite material as defined in claim 1.
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| CN114824232A (en) * | 2022-05-30 | 2022-07-29 | 常州大学 | Preparation method of nitrogen-doped porous silicon-carbon cathode |
| CN115911341A (en) * | 2023-02-06 | 2023-04-04 | 江苏正力新能电池技术有限公司 | Porous silicon-carbon negative electrode material, preparation method and application |
| CN117117159A (en) * | 2023-10-24 | 2023-11-24 | 琥崧智能装备(太仓)有限公司 | Silicon-carbon negative electrode material and preparation method and application thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN114824230A (en) * | 2022-05-27 | 2022-07-29 | 山东海科创新研究院有限公司 | Silicon-carbon graphene composite material, preparation method thereof and lithium ion battery |
| CN114824232A (en) * | 2022-05-30 | 2022-07-29 | 常州大学 | Preparation method of nitrogen-doped porous silicon-carbon cathode |
| CN114824232B (en) * | 2022-05-30 | 2023-10-03 | 常州大学 | Preparation method of nitrogen-doped porous-silicon-carbon-rich negative electrode |
| CN115911341A (en) * | 2023-02-06 | 2023-04-04 | 江苏正力新能电池技术有限公司 | Porous silicon-carbon negative electrode material, preparation method and application |
| CN117117159A (en) * | 2023-10-24 | 2023-11-24 | 琥崧智能装备(太仓)有限公司 | Silicon-carbon negative electrode material and preparation method and application thereof |
| CN117117159B (en) * | 2023-10-24 | 2023-12-26 | 琥崧智能装备(太仓)有限公司 | Silicon-carbon negative electrode material and preparation method and application thereof |
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