CN115548253A - Self-supporting silicon-carbon composite film cathode and preparation method thereof - Google Patents

Self-supporting silicon-carbon composite film cathode and preparation method thereof Download PDF

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CN115548253A
CN115548253A CN202211230478.4A CN202211230478A CN115548253A CN 115548253 A CN115548253 A CN 115548253A CN 202211230478 A CN202211230478 A CN 202211230478A CN 115548253 A CN115548253 A CN 115548253A
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罗贺斌
赵晓东
王银水
罗贺珏
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Fujian Blue Ocean & Black Stone New Material Technology Co ltd
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Abstract

The application discloses a self-supporting silicon-carbon composite film cathode and a preparation method thereof, which relate to the technical field of lithium ion batteries and comprise n nano-sheet layers and n-1 nano-particle layers, wherein n is an integer larger than or equal to 2, and each nano-particle layer is arranged between two nano-sheet layers; the nanosheet layer is composed of a two-dimensional conductive material; the nanoparticle layer includes a dispersed phase and a continuous phase; the dispersed phase is silicon nanoparticles; the continuous phase is a carbon material. The self-supporting silicon-carbon composite film negative electrode has good electrochemical performance and cycling stability.

Description

Self-supporting silicon-carbon composite film cathode and preparation method thereof
Technical Field
The application relates to the technical field of lithium ion battery cathode materials, in particular to a self-supporting silicon-carbon composite film cathode and a preparation method thereof.
Background
The lithium ion battery cathode material with high energy density and lasting cycling stability is one of the hot spots of research in the scientific community. At present, the development of lithium ion batteries is limited due to the low capacity of the traditional graphite cathode, so that a new alternative material needs to be found to replace the traditional graphite cathode material. The theoretical specific capacity of silicon is ten times higher than that of graphite, and the silicon has the characteristics of low working potential, wide source and the like, so that the silicon becomes the focus of the research of the next generation of lithium ion batteries.
Although the silicon negative electrode material has great development potential in lithium ion batteries, a plurality of challenges still exist in the current application, and the silicon negative electrode has larger volume expansion in the processes of lithium removal and lithium insertion, so that the silicon negative electrode material is easy to crack and break. The breakage of the silicon structure can lead to the deterioration of the contact between the silicon material and the current collector, and further the cycle performance of the silicon negative electrode material is gradually deteriorated, thereby being approximate to the development of the silicon negative electrode material in the lithium ion battery. In order to solve the above problems, the current research mainly prepares a novel silicon composite material, but the preparation process is complex, the cost is high, strong acid and strong base are used, and the industrialization is not facilitated, so that there is still a research space for preparing a silicon negative electrode material with good electrical properties and good cycling stability.
Disclosure of Invention
In a first aspect, the present application provides a self-supporting silicon-carbon composite thin film cathode, wherein a layer formed by silicon nanoparticles is connected between two layers of nanosheets through chemical bonds, and the nanosheets are selected from two-dimensional carbon-based materials, and in such a layered structure, the silicon nanoparticles are chemically bonded between the two-dimensional carbon-based materials, so that the displacement and falling off of the silicon nanoparticles can be inhibited, and the structural stability of the electrode is improved; in addition, when the silicon nano particles expand and contract in volume, the gaps between the layered two-dimensional carbon-based materials can provide enough expansion space for the silicon nano particles and change along with the volume change of the silicon nano particles, so that the silicon nano particles can effectively adapt to the large volume expansion of the silicon negative electrode and reduce the cracking of the electrode.
The technical scheme is as follows:
a self-supporting silicon-carbon composite film cathode comprises n nanosheet layers and n-1 nanoparticle layers, wherein n is an integer greater than or equal to 2, and each nanoparticle layer is arranged between two nanosheet layers;
the nanosheet layer is composed of a two-dimensional conductive material;
the nanoparticle layer includes a dispersed phase and a continuous phase;
the dispersed phase is silicon nanoparticles;
the continuous phase is a carbon material.
By adopting the technical scheme, the silicon nanoparticle layer is positioned between the nanosheets, the layered structure can be obtained by a simple tape casting method without using a traditional current collector and an adhesive in the structure, and in the self-supporting silicon-carbon composite film negative electrode, the silicon material is uniformly anchored in the middle of the nanosheets through chemical connection, so that the displacement and falling of the silicon nanoparticles can be inhibited, and the structural stability of the electrode is improved; gaps among the layered two-dimensional conductive materials can provide enough expansion space for the silicon nanoparticles, and the gaps change along with the volume change of the silicon nanoparticles, so that the obtained silicon anode material has excellent electrochemical performance and good cycle performance.
Optionally, the two-dimensional conductive material is selected from one or more of graphene, graphene oxide and MXenen.
By adopting the technical scheme, the graphene oxide or the MXenen can effectively adapt to the expansion and contraction of the silicon nanoparticles, accelerate the rapid transmission of ions and electrons in the electrode and improve the electrical property.
Optionally, the silicon nanoparticles have an average particle size of 20-300nm.
By adopting the technical scheme, the silicon nanoparticles in the range have better structural stability and electrical properties.
In a second aspect, the application provides a preparation method of a self-supporting silicon-carbon composite film cathode.
A preparation method of a self-supporting silicon-carbon composite film cathode comprises the following steps;
s1, dispersing the two-dimensional conductive material in a first carbon source solution to obtain a first suspension; dispersing the silicon nanoparticles in a second carbon source solution to obtain a second suspension;
s2, coating the suspension I and the suspension II obtained in the step S1 on a casting plate alternately, wherein the first layer and the last layer are both the suspension I, and drying to obtain an initial film;
and S3, carrying out heat treatment on the initial film obtained in the step S2 at 800-1200 ℃ for 1-5h in an inert gas atmosphere to obtain the self-supporting silicon-carbon composite film cathode material.
By adopting the technical scheme, the preparation method is prepared by a simple tape casting method, does not need to use the traditional current collector and adhesive, can greatly improve the capacity density of the lithium ion battery, is simple and convenient, has low cost and is easy for large-scale production; the first carbon source solution can bond the nanosheets together, and the second carbon source solution can effectively connect the silicon nanoparticles and the nanosheet layer together through subsequent casting operation, and can form a carbon coating layer on the surface of the silicon nanoparticles after heat treatment, so that the electrical property of the cathode material is improved.
Optionally, the first carbon source solution is selected from a carboxymethyl cellulose solution, and the concentration of the first carbon source solution is 0.1-10wt%.
Through adopting above-mentioned technical scheme, carboxymethyl cellulose solution can be better with the nanosheet bonding together, make things convenient for subsequent curtain coating, also make the coating structure of curtain coating coming out more stable.
Optionally, the weight ratio of the two-dimensional conductive material to the first carbon source solution is 1:1-20.
Optionally, the carbon source in the second carbon source solution is selected from one or more of asphalt powder, phenolic resin, epoxy resin, furan resin and coal tar, and the concentration of the second carbon source solution is 0.1-5wt%.
Optionally, when the first suspension and the second suspension are alternately coated on the casting plate, the thickness of each coating film is 10-100 μm.
Optionally, when the first suspension and the second suspension are coated on the casting plate alternately, the coating is kept for 5-30min after each coating.
In summary, the present application includes at least one of the following benefits:
1. in the self-supporting silicon-carbon composite film negative electrode, silicon nano particles are uniformly anchored in the middle of the nano sheet layer through chemical connection, so that the displacement and falling of the silicon nano particles can be inhibited, the structural stability of the electrode is improved, the prepared negative electrode material has high specific capacity, the traditional current collector and adhesive are not needed, and the energy density of a lithium ion battery can be greatly improved;
2. the self-supporting silicon-carbon composite film negative electrode has an excellent self-regulation function, and gaps among the nanosheets in the nanosheet layer can provide enough expansion space for silicon nanoparticles and change along with the volume change of the silicon nanoparticles, so that the self-supporting silicon-carbon composite film negative electrode can effectively adapt to the large volume expansion of the silicon negative electrode, accelerates the rapid transmission of ions and electrons in the electrode, ensures the integrity of the electrode structure and improves the electrochemical performance of the silicon negative electrode;
3. the self-supporting silicon-carbon composite film cathode is prepared by using a tape casting method, the preparation process is simple and mild, the self-supporting silicon-carbon composite film cathode has the capability of large-scale production, and the self-supporting silicon-carbon composite film cathode has a wide prospect.
Drawings
FIG. 1 is a schematic structural diagram of a self-supporting silicon carbon composite film according to the present application;
FIG. 2 is a schematic illustration of a photograph of a silicon carbon composite film according to an embodiment of the present application;
FIG. 3 is an electron microscope image of a cross-sectional structure of a silicon-carbon composite film in accordance with one embodiment of the present invention;
FIG. 4 shows the long cycle performance of the Si-C composite film negative electrode at a current density of 0.3C in the first embodiment of the present application;
FIG. 5 is a first cycle voltage curve of a silicon-carbon composite film negative electrode according to an embodiment of the present disclosure;
FIG. 6 shows the rate capability of a silicon-carbon composite film negative electrode according to an embodiment of the present invention;
FIG. 7 shows the high loading performance of a silicon-carbon composite film negative electrode according to an embodiment of the present invention.
Description of reference numerals: 1. a nanosheet layer; 2. silicon nanoparticles; 3. and a carbon coating layer.
Detailed Description
Example 1
The preparation method of the self-supporting silicon-carbon composite film cathode comprises the following steps;
(1) And dissolving 10mg of carboxymethyl cellulose in 50ml of deionized water, adding 80mg of graphene powder, performing strong ultrasonic dispersion for 5min, and continuously stirring for 5h to obtain a suspension I.
(2) And adding 200mg of asphalt powder into 50ml of acetone, continuously stirring until the asphalt powder is completely dissolved, adding 100mg of silicon nanoparticles, and stirring for 5 hours to obtain a suspension II.
(3) And setting the temperature of the casting plate to be 60 ℃, taking 20ml of the suspension, and carrying out blade coating on the casting plate at the blade coating thickness of 100 mu m for 10min to obtain a first layer of film.
(4) And spreading 10ml of the suspension on the first film with a spreading thickness of 30 μm for 10min to form a second film on the first film.
(5) 20ml of the suspension were drawn down onto the second film to a thickness of 100. Mu.m for 10min until completely dried, giving the initial film.
(6) And (5) peeling off the initial film obtained in the step (5) from the casting plate, and transferring the initial film to a tubular furnace for heat treatment under the protection of nitrogen atmosphere. Placing the tube furnace at 2 deg.C for min -1 Heating to 900 ℃ at the rate of the temperature rise, preserving the heat for 2 hours, and finally cooling to room temperature along with the furnace to finally obtain the self-supporting silicon-carbon composite film.
(7) And cutting the prepared self-supporting silicon-carbon composite film into a circular sheet with the diameter of 12mm to be used as a self-supporting cathode.
Example 2
The preparation method of the self-supporting silicon-carbon composite film cathode comprises the following steps;
(1) Dissolving 10mg of carboxymethyl cellulose in 50ml of deionized water, adding 80mg of graphene oxide powder, performing strong ultrasonic dispersion for 5min, and continuously stirring for 5h to obtain a suspension I.
(2) Adding 250mg of phenolic resin into 50ml of ethanol, continuously stirring until the phenolic resin is completely dissolved, adding 100mg of silicon nanoparticles, and stirring for 5 hours to obtain a suspension II.
(3) And setting the temperature of the casting plate to be 100 ℃, taking 20ml of the suspension, and carrying out blade coating on the casting plate at a blade coating thickness of 100 mu m for 10min to obtain a first layer of film.
(4) And spreading 10ml of the suspension on the first film with a spreading thickness of 30 μm for 10min to form a second film on the first film.
(5) 20ml of the suspension were drawn down onto the second film to a thickness of 100. Mu.m for 10min until completely dried, giving the initial film.
(6) And peeling the obtained initial film from the casting plate, and transferring the initial film to a tubular furnace for heat treatment under the protection of nitrogen atmosphere. Placing the tube furnace at 2 deg.C for min -1 Heating to 1000 ℃ at the rate of the temperature, preserving the heat for 2 hours, and finally cooling to room temperature along with the furnace to finally obtain the self-supporting silicon-carbon composite film.
(7) And cutting the prepared self-supporting silicon-carbon composite film into a circular sheet with the diameter of 12mm to be used as a self-supporting cathode.
Example 3
The preparation method of the self-supporting silicon-carbon composite film cathode comprises the following steps;
(1) Dissolving 10mg of carboxymethyl cellulose in 50ml of deionized water, adding 100mg of dispersed MXene nanosheets, strongly ultrasonically dispersing for 10min, and continuously stirring for 5h to obtain a suspension I.
(2) And adding 250mg of epoxy resin into 50ml of ethanol, continuously stirring until the epoxy resin is completely dissolved, adding 100mg of silicon nanoparticles, and stirring for 5 hours to obtain a suspension II.
(3) And setting the temperature of the casting plate to 80 ℃, taking 20ml of the suspension, and carrying out blade coating on the casting plate at a blade coating thickness of 100 mu m for 10min to obtain a first layer of film.
(4) Spreading 10ml of the suspension on the first film with a thickness of 30 μm for 10min to form a second film on the first film
(5) And taking 20ml of the suspension, and coating the suspension on the second film by one-time scraping to form a coating with the thickness of 100 mu m, and keeping for 10min until the coating is completely dried to obtain an initial film.
(6) And peeling the obtained initial film from the casting plate, and transferring the initial film to a tubular furnace for heat treatment under the protection of nitrogen atmosphere. Placing the tube furnace at 2 deg.C for min -1 Heating to 1000 ℃, preserving the heat for 2 hours, and finally cooling to room temperature along with the furnace to finally obtain the self-supporting silicon-carbon composite film.
(7) And cutting the prepared self-supporting silicon-carbon composite film into a circular sheet with the diameter of 12mm to be used as a self-supporting cathode.
Example 4
The preparation method of the self-supporting silicon-carbon composite film cathode comprises the following steps;
(1) Dissolving 10mg of carboxymethyl cellulose in 50ml of deionized water, adding 80mg of graphene oxide powder, performing strong ultrasonic dispersion for 20min, and continuously stirring for 5h to obtain a suspension I.
(2) And adding 200mg of asphalt powder into 50ml of acetone, continuously stirring until the asphalt powder is completely dissolved, adding 100mg of silicon nanoparticles, and stirring for 5 hours to obtain a suspension II.
(3) And setting the temperature of the casting plate to be 60 ℃, taking 20ml of the suspension, and carrying out blade coating on the casting plate at the blade coating thickness of 100 mu m for 10min to obtain a first layer of film.
(4) And spreading 10ml of the suspension on the first film with a spreading thickness of 30 μm for 10min to form a second film on the first film.
(5) 20ml of the suspension were drawn down onto the second film to a thickness of 100. Mu.m for 10min until completely dried, giving the initial film.
(6) And peeling the obtained initial film from the casting plate, and transferring the initial film to a tubular furnace for heat treatment under the protection of nitrogen atmosphere. Placing the tube furnace at 2 deg.C for min -1 Heating to 900 ℃ at the rate of the temperature rise, preserving the heat for 2 hours, and finally cooling to room temperature along with the furnace to finally obtain the supporting silicon-carbon composite film.
(7) And cutting the prepared supporting silicon-carbon composite film into a circular sheet with the diameter of 12mm to be used as a self-supporting cathode.
Example 5
The preparation method of the self-supporting silicon-carbon composite film cathode comprises the following steps;
(1) And dissolving 10mg of carboxymethyl cellulose in 50ml of deionized water, adding 100mg of graphene powder, performing strong ultrasonic dispersion for 5min, and continuously stirring for 5h to obtain a suspension I.
(2) Adding 250g of phenolic resin into 50ml of acetone, continuously stirring until the phenolic resin is completely dissolved, adding 100mg of silicon nanoparticles, and stirring for 5 hours to obtain a suspension II.
(3) And setting the temperature of the casting plate to be 50 ℃, taking 20ml of the suspension, and carrying out scratch coating on the casting plate for 10min to obtain a first layer of film, wherein the scratch coating thickness is 100 mu m.
(4) And spreading 10ml of the suspension on the first film with a spreading thickness of 30 μm for 10min to form a second film on the first film.
(5) 20ml of the suspension were drawn down onto the second film to a thickness of 100. Mu.m for 10min until completely dry.
(6) And peeling the obtained silicon-carbon composite film from the casting plate, and transferring the silicon-carbon composite film to a tubular furnace for heat treatment under the protection of nitrogen atmosphere. Placing the tube furnace at 2 deg.C for min -1 Heating to 900 ℃ at the rate of the temperature rise, preserving the heat for 2 hours, and finally cooling to room temperature along with the furnace to finally obtain the self-supporting silicon-carbon composite film.
(7) And cutting the prepared self-supporting silicon-carbon composite film into a circular sheet with the diameter of 12mm to be used as a self-supporting cathode.
Comparative example 1
The preparation procedure of this comparative example included the following steps,
(1) 200mg of asphalt powder is added into 50ml of acetone and continuously stirred until the asphalt powder is completely dissolved, and then 100mg of silicon nano particles are added and stirred for 5 hours to obtain a suspension.
(2) And setting the temperature of the casting plate to 60 ℃, taking 20ml of the suspension in the step (1) to be coated on the casting plate, wherein the coating thickness is 100 mu m, and keeping for 10min.
(3) And peeling the obtained film from the casting plate, and transferring the film to a tubular furnace for heat treatment under the protection of nitrogen atmosphere. Placing the tube furnace at 2 deg.C for min -1 Heating to 900 ℃ at the rate of the temperature rise, preserving the heat for 2 hours, and finally cooling to room temperature along with the furnace to finally obtain the two-dimensional silicon-carbon composite film.
(4) And cutting the prepared two-dimensional silicon-carbon composite film into a circular sheet with the diameter of 12mm to be used as a self-supporting cathode.
Comparative example 2
The process steps and raw materials of the comparative example and example 1 are the same, except that graphene powder is not added to the first suspension.
Comparative example 3
The process steps of this comparative example are as follows;
(1) And adding 200mg of asphalt powder into 50ml of acetone, continuously stirring until the asphalt powder is completely dissolved, adding 80mg of graphene powder and 100mg of silicon nanoparticles, and stirring for 5 hours to obtain a suspension.
(2) And setting the temperature of the casting plate to be 60 ℃, taking 50ml of the suspension in the step (1) to be coated on the casting plate by a doctor blade, wherein the doctor blade is 230 mu m in thickness and keeping for 10min until the suspension is completely dried to obtain a film.
(3) Peeling the film obtained in the step (2) from the casting plate, transferring the film to a tubular furnace, carrying out heat treatment in the protection of nitrogen atmosphere, and enabling the tubular furnace to be at 2 ℃ for min -1 Heating to 900 ℃ at the rate of the temperature, preserving the heat for 2 hours, and finally cooling to room temperature along with the furnace to finally obtain the silicon-carbon composite film.
(4) And cutting the prepared silicon-carbon composite film into a circular sheet with the diameter of 12mm to be used as a self-supporting cathode.
Performance testing
The films prepared in all the examples above were cut into disks with a diameter of 1mm, which were used as self-supporting cathodes in lithium ion batteries, and the batteries were assembled in an argon-filled glove box (moisture content < 0.1ppm, oxygen content < 0.1 ppm) with lithium disks as the counter electrode, and the electrolyte was a mixed solution of 1MLiPF6 in 90wt% of vinyl carbonate and diethyl carbonate in a volume ratio of 1:1 and 10wt% of fluoroethylene carbonate. The septum was Celgard 2400. And (3) carrying out constant-current charge and discharge test at 0.01-1.5V by using a Newware battery test system. Specific first charge capacities and 300 cycle retention rates of examples 1 to 5 and comparative examples 1 to 3 are shown in the following table.
TABLE 1 Performance test tables for examples 1 to 5 and comparative examples 1 to 3
Figure BDA0003880910340000071
Figure BDA0003880910340000081
The self-supporting silicon-carbon composite film can be prepared by a simple casting method without using the traditional current collector and adhesive. Referring to fig. 1, in the structure of the silicon-carbon composite film, two nanosheet layers 1 are included, a silicon nanoparticle layer formed by silicon nanoparticles 3 is located between the nanosheet layers 1, and the surface of the silicon nanoparticles is coated with a carbon coating layer. The silicon nanoparticles 1 are anchored between the two nano-sheet layers 1 through chemical connection, so that the displacement and falling of the silicon nanoparticles can be inhibited, and the structural stability of the electrode is improved. Referring to fig. 2 and 3, in the nanosheet layer, a plurality of gaps exist between the carbon nanosheets, and the gaps between the layered carbon materials can provide enough expansion space for the silicon nanoparticles and change along with the volume change of the silicon nanoparticles, so that the large volume expansion of the silicon cathode can be effectively accommodated.
As can be seen from comparison of the test data of example 1 and comparative examples 1 to 3, the cycle performance of the anode material can be improved by the layered structure of C-Si-C in the present application. The silicon nanoparticles are uniformly anchored in the middle of the nanosheet layer through chemical connection, so that the displacement and falling-off of the silicon nanoparticles can be inhibited, and the structural stability of the electrode is improved; and the nanosheet layer can effectively adapt to the large volume expansion of the silicon cathode, so that the electrochemical performance is maintained. It can be seen from the cycling voltage curves, rate capability and high load performance graphs of fig. 5, 6 and 7 that the self-supporting silicon-carbon composite film negative electrode in example 1 has good cycling stability.
The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims (10)

1. A self-supporting silicon-carbon composite film cathode is characterized in that: the nano-particle layer structure comprises n nano-sheet layers and n-1 nano-particle layers, wherein n is an integer larger than or equal to 2, and each nano-particle layer is arranged between two nano-sheet layers;
the nanosheet layer is composed of a two-dimensional conductive material;
the nanoparticle layer includes a dispersed phase and a continuous phase;
the dispersed phase is silicon nanoparticles;
the continuous phase is a carbon material.
2. The self-supporting silicon-carbon composite film negative electrode as claimed in claim 1, wherein the two-dimensional conductive material is selected from one or more of graphene, graphene oxide and MXenen.
3. The self-supporting silicon-carbon composite film negative electrode as claimed in claim 1, wherein the average particle size of the silicon nanoparticles is 20-300nm.
4. A method for preparing a self-supporting silicon carbon composite film negative electrode as claimed in any one of claims 1 to 3, comprising the steps of;
s1, dispersing the two-dimensional conductive material in a first carbon source solution to obtain a first suspension; dispersing the silicon nanoparticles in a second carbon source solution to obtain a second suspension;
s2, coating the suspension I and the suspension II obtained in the step S1 on a casting plate alternately, wherein the first layer and the last layer are both the suspension I, and drying to obtain an initial film;
and S3, carrying out heat treatment on the initial film obtained in the step S2 at 800-1200 ℃ for 1-5h in an inert gas atmosphere to obtain the self-supporting silicon-carbon composite film cathode material.
5. The method for preparing the self-supporting silicon-carbon composite film negative electrode as claimed in claim 4, wherein the first carbon source solution is selected from a carboxymethyl cellulose solution, and the concentration of the first carbon source solution is 0.1-10wt%.
6. The preparation method of the self-supporting silicon-carbon composite film anode as claimed in claim 4, wherein the weight ratio of the two-dimensional conductive material to the first carbon source solution is 1:1-20.
7. The preparation method of the self-supporting silicon-carbon composite film negative electrode as claimed in claim 4, wherein the carbon source in the second carbon source solution is selected from one or more of asphalt powder, phenolic resin, epoxy resin, furan resin and coal tar, and the concentration of the second carbon source solution is 0.1-5wt%.
8. The preparation method of the self-supporting silicon-carbon composite film anode as claimed in claim 4, wherein the weight ratio of the silicon nanoparticles to the second carbon source solution is 1:5-100.
9. The method for preparing the self-supporting silicon-carbon composite film negative electrode as claimed in claim 4, wherein when the first suspension and the second suspension are alternately coated on the casting plate, the thickness of each coating film is 10-100 μm.
10. The method for preparing the self-supporting silicon-carbon composite film negative electrode as claimed in claim 4, wherein the suspension I and the suspension II are alternately coated on the casting plate and kept for 5-30min after each coating.
CN202211230478.4A 2022-09-30 2022-09-30 Self-supporting silicon-carbon composite film cathode and preparation method thereof Pending CN115548253A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115763822A (en) * 2023-01-06 2023-03-07 碳佳(北京)科技有限公司 Silicon-carbon negative electrode composite material, application and lithium battery

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115763822A (en) * 2023-01-06 2023-03-07 碳佳(北京)科技有限公司 Silicon-carbon negative electrode composite material, application and lithium battery
CN115763822B (en) * 2023-01-06 2023-08-04 碳佳(北京)科技有限公司 Silicon-carbon negative electrode composite material, application and lithium battery

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