CN114229854A - Preparation method of silicon-oxygen-carbon composite material, negative plate and battery - Google Patents

Preparation method of silicon-oxygen-carbon composite material, negative plate and battery Download PDF

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CN114229854A
CN114229854A CN202111552111.XA CN202111552111A CN114229854A CN 114229854 A CN114229854 A CN 114229854A CN 202111552111 A CN202111552111 A CN 202111552111A CN 114229854 A CN114229854 A CN 114229854A
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silicon
oxygen
composite material
carbon composite
powder
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薛明华
宗鑫
赵建文
马海安
田宗浩
陈喜清
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Xinjiang Jingshuo New Material Co ltd
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Abstract

The invention provides a preparation method of a silicon-oxygen-carbon composite material, a negative plate and a battery, and the preparation method of the silicon-oxygen-carbon composite material comprises the following steps: mixing metal silicon powder, silicon dioxide powder and magnesium powder to obtain a mixed material; and putting the mixed material into a reactor, introducing carbon dioxide gas, igniting the mixed material to initiate a self-propagating reaction, and obtaining the silicon-oxygen-carbon composite material after the reaction is finished. The invention provides a method for preparing a silicon-oxygen-carbon composite material by adopting a self-propagating reaction, which has the advantages of simple operation, easily obtained and cheap raw materials and greatly reduced production cost of the silicon-oxygen-carbon composite material. The silicon-oxygen-carbon composite material prepared by the method has the advantages of adjustable oxygen content, high purity, small crystal particles, obvious reduction of the cyclic expansion of the material, improvement of the specific capacity of the material and improvement of the cycle life of the material.

Description

Preparation method of silicon-oxygen-carbon composite material, negative plate and battery
Technical Field
The invention relates to the technical field of preparation of silicon-oxygen-carbon composite materials, and particularly relates to a preparation method of a silicon-oxygen-carbon composite material, a negative plate and a battery.
Background
Lithium ion batteries have been widely used in the fields of portable consumer electronics, electric tools, medical electronics, and the like because of their excellent properties. Meanwhile, the method has good application prospect in the fields of pure electric vehicles, hybrid electric vehicles, energy storage and the like. The current commercialized lithium ion battery cathode material is mainly made of the traditional graphite cathode material, the actual specific capacity of the lithium ion battery cathode material is close to the theoretical value of 372mAh/g, and the improvement space is difficult. The silicon negative electrode material has high specific capacity (4200mAh/g) and volume energy density, does not cause the phenomenon of surface lithium precipitation when applied to a lithium ion battery, has good safety, and has obvious advantages compared with other high specific capacity materials. However, the silicon negative electrode material also has problems such as low cycle life, large volume change, continuous generation of SEI film, and the like.
In view of the problems of the silicon negative electrode material, it is found that the silicon is partially oxidized to form silicon oxide SiOx (0< x <2), and the volume change of the material is alleviated by sacrificing the specific capacity of the part, so that the cycling stability of the silicon material in the application of the battery can be remarkably improved. However, the silicon oxide has the problems of low coulombic efficiency, harsh preparation conditions, difficult batch production and the like for the first time, the industrial production of the domestic silicon oxide mainly adopts a high-temperature evaporation, condensation and collection process, the yield is low, the energy consumption is high, the single production of monomer production equipment is only 50 kilograms at most, and the energy consumption occupies about 35 percent of the whole production cost.
In order to solve the problem of low first coulombic efficiency when silicon oxide is used as a negative electrode material, the first coulombic efficiency, reversible capacity and cycling stability are improved by adopting a carbon-coating treatment mode on the silicon oxide at present. The main carbon coating modes comprise sand grinding disproportionation, ball milling spray drying, pitch solid phase carbon coating, phenolic resin liquid phase carbon coating, CVD gas phase carbon coating and the like, but the carbon coating modes have the problems of higher relative cost, low yield, high risk, high industrialization difficulty and the like.
Disclosure of Invention
In view of the above, the invention provides a preparation method of a silicon-oxygen-carbon composite material, a negative plate and a battery, which are used for solving the problems of high relative cost, low yield, high risk, high industrialization difficulty and the like in the prior art.
In order to solve the technical problems, the invention adopts the following technical scheme:
in a first aspect, the invention provides a preparation method of a silicon-oxygen-carbon composite material, wherein the preparation method comprises the following steps:
mixing metal silicon powder, silicon dioxide powder and magnesium powder to obtain a mixed material; and putting the mixed material into a reactor, introducing carbon dioxide gas, igniting the mixed material to initiate a self-propagating reaction, and obtaining the silicon-oxygen-carbon composite material after the reaction is finished.
Further, placing the mixed material in a reactor, vacuumizing the reactor, closing a vacuumizing system when the vacuum degree is less than or equal to 10Pa, and introducing carbon dioxide gas.
Further, the reaction temperature was controlled to be maintained at 1300-1700 ℃ by controlling the flow rate of the carbon dioxide gas during the reaction.
Further, the metal silicon powder, the silicon dioxide powder, the magnesium powder and the carbon dioxide are mixed according to a molar ratio of 1: (0.5-1.5): (2-4): (1.5-2.5) in proportion.
Further, the addition amount of the raw materials is 5-10kg/h, and the flow velocity of the carbon dioxide gas is 2-6 m3/h。
Further, the particle size D50 of the metal silicon powder is 5-20 μm, and/or
The particle diameter D50 of the silicon dioxide powder is 5-20 mu m, and/or
The particle size D50 of the magnesium powder is 5-20 μm.
Further, the preparation method further comprises the following steps: and carrying out acid washing on the silicon-oxygen-carbon composite material.
Further, the acid cleaning method for the silicon-oxygen-carbon composite material comprises the following steps: and crushing the silicon-oxygen-carbon composite material into particles with the particle size of less than or equal to 50 mu m, and then carrying out acid washing.
In a second aspect, the invention provides a negative plate, which comprises the composite negative electrode material prepared by the preparation method.
In a third aspect, the invention provides a battery comprising the negative electrode sheet as described above.
The technical scheme of the invention has the following beneficial effects:
the invention provides a preparation method of a silicon-oxygen-carbon composite material, which comprises the following steps: mixing metal silicon powder, silicon dioxide powder and magnesium powder to obtain a mixed material; and putting the mixed material into a reactor, introducing carbon dioxide gas, igniting the mixed material to initiate a self-propagating reaction, and obtaining the silicon-oxygen-carbon composite material after the reaction is finished. The invention provides a method for preparing a silicon-oxygen-carbon composite material by adopting a self-propagating reaction, which has the advantages of simple operation, easily obtained and cheap raw materials and greatly reduced production cost of the silicon-oxygen-carbon composite material. The silicon-oxygen-carbon composite material prepared by the method has the advantages of adjustable oxygen content, high purity, small crystal particles, obvious reduction of the cyclic expansion of the material, improvement of the specific capacity of the material and improvement of the cycle life of the material.
Drawings
FIG. 1 is a flow chart of a process for preparing a silicon-oxygen-carbon composite anode material by a self-propagating combustion mode;
fig. 2 is an SEM photograph of the silicon-oxygen-carbon composite anode material prepared in example 1;
FIG. 3 is an XRD pattern of a silicon-oxygen-carbon composite anode material prepared in example 1;
fig. 4 is a performance test chart of the button cell prepared in example 1;
fig. 5 is a performance test chart of the button cell prepared in example 2.
Detailed Description
For a further understanding of the invention, reference will now be made to the preferred embodiments of the invention in conjunction with the following examples, but it will be understood that the description is intended to illustrate the features and advantages of the invention further, and not to limit the invention.
In a first aspect, the invention provides a preparation method of a silicon-oxygen-carbon composite material, wherein the preparation method comprises the following steps:
mixing metal silicon powder, silicon dioxide powder and magnesium powder to obtain a mixed material; and putting the mixed material into a reactor, introducing carbon dioxide gas, igniting the mixed material to initiate a self-propagating reaction, and obtaining the silicon-oxygen-carbon composite material after the reaction is finished.
The invention provides a method for preparing silicon-oxygen-carbon composite material by adopting self-propagating reaction, wherein metal silicon powder, silicon dioxide powder, magnesium powder mixture and carbon dioxide gas are used as raw materials, carbon dioxide is introduced into a reactor filled with the metal silicon powder, the silicon dioxide powder and the magnesium powder mixture, and the mixture is ignited to carry out reaction (see formula 3). The combustion reaction of magnesium and carbon dioxide gas (see formula 1) is an oxidation-reduction reaction and generates a large amount of heat during the reaction, so that the heat generation can be used to promote the reaction of silicon metal powder and silicon dioxide powder to produce silicon oxide SiOx(see formula 2) and produces disproportionation. During the reaction, carbon generated in the combustion reaction of magnesium and carbon dioxide can react with silicon oxide SiOxCoating and continuously roasting at high temperature to generate SiOxAnd C, a composite material. The flow chart of the method for preparing the silicon-oxygen-carbon composite material by adopting the self-propagating combustion reaction in the invention is shown in figure 1.
2Mg+CO2→ C +2MgO formula 1;
Si+SiO2→2SiOx，SiOxmiddle 0<X<2, formula 2;
Si+SiO2+2Mg+CO2→2SiOx+C+2MgO，SiOxmiddle 0<X<2 and 3.
In the present invention, the magnesium powder is selected as the raw material for the reaction because the magnesium powder is easily ignited and can emit a large amount of heat during combustion, and because the magnesium and its oxide are mixed in a small amount in the composite material, which has no adverse effect on the performance of the composite material.
The invention provides a method for preparing a silicon-oxygen-carbon composite material by adopting a self-propagating reaction, which has the advantages of simple operation, easily obtained and cheap raw materials and greatly reduced production cost of the silicon-oxygen-carbon composite material. The silicon-oxygen-carbon composite material prepared by the method has the advantages of adjustable oxygen content, high purity, small crystal particles, obvious reduction of the cyclic expansion of the material, improvement of the specific capacity of the material and improvement of the cycle life of the material. In the whole reaction process, silicon powder and silicon dioxide generate silicon monoxide in the process of providing energy by combusting magnesium powder and carbon dioxide gas, a carbon coating layer is generated on the surface of the silicon monoxide, and the silicon monoxide generates disproportionation reaction in the reaction process, so that the pre-expansion of the silicon-oxygen-carbon composite material is realized, and the expansion problem of the silicon-oxygen-carbon composite cathode material in an electric core system is further solved.
According to some embodiments of the invention, the method of igniting the mixture to initiate an auto-propagating reaction may comprise: the tungsten filament wound into a spiral shape is arranged in the reactor, and current is continuously introduced to ensure that the heating temperature of the tungsten filament reaches the reaction temperature of magnesium and carbon dioxide in the mixed material, so that the self-propagating reaction can be initiated.
According to some embodiments of the invention, the mixture is placed in a reactor, the reactor is evacuated, the evacuation system is closed when the degree of vacuum is less than or equal to 10Pa, and carbon dioxide gas is introduced.
According to some embodiments of the present invention, the reaction temperature is controlled to be maintained at 1300-1700 ℃ by controlling the flow rate of the carbon dioxide gas during the reaction.
In the present invention, the opening degree of the carbon dioxide gas supply valve is adjusted, the temperature in the reactor is maintained by observing the flow meter, and if the actual temperature in the reactor is lower than the set temperature, the supply amount of the carbon dioxide gas per unit time needs to be increased; on the other hand, the supply amount of carbon dioxide gas per unit time needs to be reduced. In short, the temperature in the reactor is in direct proportion to the flow rate of the carbon dioxide gas, and in order to ensure the uniformity of the product and the reaction efficiency, the temperature in the reactor needs to be maintained within a permissible deviation range of the set temperature after the reaction is started, and a general permissible deviation range is within ± 50 ℃.
According to some embodiments of the invention, the silicon metal powder, the silicon dioxide powder, the magnesium powder and the carbon dioxide are mixed in a molar ratio of 1: (0.5-1.5): (2-4): (1.5-2.5) in proportion. Preferably, the metal silicon powder, the silicon dioxide powder, the magnesium powder and the carbon dioxide are mixed according to a molar ratio of 1:1: 4: 2, and mixing.
According to some embodiments of the invention, the raw material is added in an amount of 5-10kg/h, and the flow rate of the carbon dioxide gas is 2-6 m3/h。
According to some embodiments of the invention, the particle size D50 of the metal silicon powder is 5-20 μm, and/or the particle size D50 of the silicon dioxide powder is 5-20 μm, and/or the particle size D50 of the magnesium powder is 5-20 μm.
According to some embodiments of the invention, the purity of the metallic silicon powder is > 99%, and/or the purity of the silica powder is > 99.5%, and/or the purity of the magnesium powder is > 99.9%, and/or the purity of the carbon dioxide gas is > 99.99%.
According to some embodiments of the present invention, the metal silicon powder, the silicon dioxide powder and the magnesium powder are mixed to obtain a mixed material, and the mixed material is dried before being placed in the reactor.
According to some embodiments of the invention, further comprising: and carrying out acid washing on the silicon-oxygen-carbon composite material. In the invention, the silicon-oxygen-carbon composite material obtained through the self-propagating reaction also comprises impurities such as magnesium oxide generated by the reaction, magnesium which is not completely reacted and the like, so the silicon-oxygen-carbon composite material also needs to be subjected to acid washing for impurity removal.
According to some embodiments of the invention, the method of acid washing the silicon oxygen carbon composite material comprises: the silicon-oxygen-carbon composite material is crushed into particles with the particle size of less than or equal to 50 mu m and then is subjected to acid cleaning, and hydrochloric acid can be used for acid cleaning to remove magnesium oxide in the material and most of metal impurities and other impurities in the raw material.
In a second aspect, the invention provides a negative plate, which comprises the composite negative electrode material prepared by the preparation method.
In a third aspect, the invention provides a battery comprising the negative electrode sheet as described above. Compared with the silicon negative electrode material, the silicon-oxygen-carbon composite material prepared by the invention obviously reduces the cyclic expansion of the material, and compared with the traditional graphite material, the specific capacity and the volume energy density of the material are obviously improved by utilizing the silicon-oxygen-carbon composite material prepared by the invention. The battery prepared by using the silicon-oxygen-carbon composite material as the cathode material can improve the energy density and the cycle life of the battery.
The invention is further illustrated by the following specific examples.
Example 1
A method for preparing a silicon-oxygen-carbon composite cathode material of a lithium ion battery by adopting a self-propagating combustion mode comprises the following steps:
s1, selecting metal silicon powder with the particle size D50 of 10 mu m and the purity of more than 99 percent; selecting silicon dioxide powder with the particle size D50 of 10 mu m and the purity of more than 99.5 percent; selecting magnesium powder with the particle size D50 of 10 mu m and the purity of more than 99.9 percent; weighing silicon powder, silicon dioxide powder and magnesium powder according to the molar ratio of 1:1:4, and then putting the weighed materials into a high-efficiency mixer for fully mixing to obtain a mixed material; putting the mixed raw materials into a vacuum oven for drying, wherein the drying temperature is set to be 180 ℃, and the drying time is 12 hours;
and S2, connecting a carbon dioxide gas line with a flow controller to the reactor, and arranging a tungsten wire wound into a spiral shape, wherein the tungsten wire is connected with a power supply. And (4) uniformly spreading 10kg of the dried mixed material in the step (S1) in a reactor, opening a carbon dioxide gas valve and a flow meter, filling carbon dioxide gas into the reactor, and stopping vacuumizing when the vacuum degree reaches 5-10 Pa. Switching on a power supply to heat the tungsten filament so as to ignite the raw materials in the reactor;
s3, monitoring the temperature and pressure in the reactor, controlling the temperature in the reactor within the range of 1400 ℃ and 1500 ℃ by controlling the flow of the carbon dioxide gas, and ensuring that the self-propagating reaction is carried out for 1.5-2 hours;
and S4, when the temperature in the reactor is obviously reduced and the pressure is obviously increased, the self-propagating reaction is proved to be fully completed, and the carbon dioxide gas valve is closed. And opening the reactor and taking out the materials after the temperature in the reactor is reduced to the normal temperature. And crushing the taken materials to be less than 50 mu m. And (3) carrying out acid washing on the crushed material, wherein the acid is hydrochloric acid. And (4) drying the pickled material in a vacuum oven. And (3) putting the dried material into a ball mill for ball milling, crushing and mixing to finally obtain the silicon-oxygen-carbon composite material.
And (3) testing:
and (4) SEM test: taking an SEM photograph of the silicon-oxygen-carbon composite material prepared in this example, fig. 2 is an SEM photograph of the silicon-oxygen-carbon composite material prepared in this example, and it can be seen from fig. 2 that: the particle size of the silicon-oxygen-carbon composite material prepared by the invention is about 4 mu m.
XRD test: an XRD test is performed on the silicon-oxygen-carbon composite material prepared in this example, wherein fig. 3 is an XRD pattern of the silicon-oxygen-carbon composite material prepared in this example, and as can be seen from fig. 3, the substance is a mixed phase of silicon, silicon dioxide and carbon, and has a distinct C peak and silicon peak at 27 to 28 °, and a distinct silicon dioxide peak at 22 °, which indicates that the preparation method provided in this example indeed synthesizes the silicon-oxygen-carbon composite material.
And (4) testing the fruit by using a button cell: the prepared silicon-oxygen-carbon composite material is made into a button cell, and the slurry proportion of the button cell is as follows: SP: CMC: SBR 93.0: 2.0: 2.0: 3.0 (wherein, the active material specific capacity in this example is <460mAh/g), under the conditions of charging voltage (2V) and rate discharge (0.02C, 0.005V), the test result is shown in fig. 4, and as can be seen from fig. 4, the capacity of the button cell prepared in this example is 1730mAh/g, and the first effect is 79.5%.
Example 2
A method for preparing a silicon-oxygen-carbon composite cathode material of a lithium ion battery by adopting a self-propagating combustion mode comprises the following steps:
s1, selecting metal silicon powder with the particle size D50 of 15 mu m and the purity of more than 99 percent; selecting silicon dioxide powder with the particle size D50 of 15 mu m and the purity of more than 99.5 percent; selecting magnesium powder with the particle size D50 of 15 mu m and the purity of more than 99.9 percent; weighing silicon powder, silicon dioxide powder and magnesium powder according to the molar ratio of 1:1:4, and then putting the weighed materials into a high-efficiency mixer for fully mixing to obtain a mixed material; putting the mixed raw materials into a vacuum oven for drying, wherein the drying temperature is set to be 180 ℃, and the drying time is 12 hours;
and S2, connecting a carbon dioxide gas line with a flow controller to the reactor, and arranging a tungsten wire wound into a spiral shape, wherein the tungsten wire is connected with a power supply. And (4) uniformly spreading 10kg of the dried mixed material in the step (S1) in a reactor, opening a carbon dioxide gas valve and a flow meter, filling carbon dioxide gas into the reactor, and stopping vacuumizing when the vacuum degree reaches 5-10 Pa. Switching on a power supply to heat the tungsten filament so as to ignite the raw materials in the reactor;
s3, monitoring the temperature and pressure in the reactor, controlling the temperature in the reactor within the range of 1500-1600 ℃ by controlling the flow of the carbon dioxide gas, and ensuring the self-propagating reaction to be carried out for 1-1.5 hours;
and S4, when the temperature in the reactor is obviously reduced and the pressure is obviously increased, the self-propagating reaction is proved to be fully completed, and the carbon dioxide gas valve is closed. And opening the reactor and taking out the materials after the temperature in the reactor is reduced to the normal temperature. And crushing the taken materials to be less than 50 mu m. And (3) carrying out acid washing on the crushed material, wherein the acid is hydrochloric acid. And (4) drying the pickled material in a vacuum oven. And (3) putting the dried materials into a ball mill for ball milling, crushing and mixing to finally obtain the silicon-oxygen-carbon composite material.
And (3) button cell testing: the prepared material is prepared into a button cell, and the slurry proportion of the button cell is as follows: CMC: SBR 89.5: 3.5: 3.0: 4.0 (wherein, the specific capacity of the active material in this example is 460-580mAh/g), the button cell prepared in this example is tested under the conditions of charging voltage (1V) and rate discharge (0.1C, 0.005V), and the test result is shown in FIG. 5, and as can be seen from FIG. 5, the capacity of the button cell prepared in this example is 1811.5mAh/g, and the first effect is 75.6%.
Unless defined otherwise, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention belongs. The use of "first," "second," and similar terms in the present application do not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another. The terms "connected" or "coupled" and the like are not restricted to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships are changed accordingly.
While the foregoing is directed to the preferred embodiment of the present invention, it will be understood by those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (10)

1. The preparation method of the silicon-oxygen-carbon composite material is characterized by comprising the following steps:
mixing metal silicon powder, silicon dioxide powder and magnesium powder to obtain a mixed material; and putting the mixed material into a reactor, introducing carbon dioxide gas, igniting the mixed material to initiate a self-propagating reaction, and obtaining the silicon-oxygen-carbon composite material after the reaction is finished.
2. The preparation method according to claim 1, wherein the mixed material is placed in a reactor, the reactor is vacuumized, and carbon dioxide gas is introduced when the degree of vacuum is less than or equal to 10 Pa.
3. The method as claimed in claim 1, wherein the reaction temperature is controlled to be maintained at 1300-1700 ℃ by controlling the flow rate of the carbon dioxide gas during the reaction.
4. The preparation method according to claim 1, wherein the metal silicon powder, the silica powder, the magnesium powder and the carbon dioxide are mixed in a molar ratio of 1: (0.5-1.5): (2-4): (1.5-2.5) in proportion.
5. The production method according to claim 1, wherein the amount of the raw material added is 5 to 10kg/h, and the flow rate of the carbon dioxide gas is 2 to 6m3/h。
6. The preparation method according to claim 1, wherein the particle size D50 of the metal silicon powder is 5-20 μm, and/or
The particle diameter D50 of the silicon dioxide powder is 5-20 mu m, and/or
The particle size D50 of the magnesium powder is 5-20 μm.
7. The method of claim 1, further comprising:
and carrying out acid washing on the silicon-oxygen-carbon composite material.
8. The preparation method of claim 7, wherein the silicon-oxygen-carbon composite material is pickled by the following steps:
and crushing the silicon-oxygen-carbon composite material into particles with the particle size of less than or equal to 50um, and then carrying out acid washing.
9. A negative electrode sheet, characterized by comprising the composite negative electrode material produced by the production method according to any one of claims 1 to 8.
10. A battery comprising the negative electrode sheet as claimed in claim 9.
CN202111552111.XA 2021-12-17 2021-12-17 Preparation method of silicon-oxygen-carbon composite material, negative plate and battery Pending CN114229854A (en)

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Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105826527A (en) * 2016-03-22 2016-08-03 浙江大学 Porous silicon-carbon composite material and preparation method and application thereof
CN106025220A (en) * 2016-06-24 2016-10-12 中天储能科技有限公司 Silicon oxide-based silicon-oxygen-carbon composite material and preparation method and application thereof
CN108539173A (en) * 2018-04-20 2018-09-14 中国科学院理化技术研究所 A kind of preparation method of graphene coated silicon composite
CN111115639A (en) * 2019-12-25 2020-05-08 湖北万润新能源科技发展有限公司 Preparation of SiO by centering reactionxMethod and application of @ C material
CN111313029A (en) * 2020-02-28 2020-06-19 湖南农业大学 Closely-combined high-performance silicon/graphitized carbon composite material with hollow structure and preparation method and application thereof
CN111342014A (en) * 2020-03-05 2020-06-26 上海电气集团股份有限公司 Silicon-carbon negative electrode material of lithium ion battery and preparation method thereof
CN112018334A (en) * 2019-05-28 2020-12-01 贝特瑞新材料集团股份有限公司 Silicon oxide/carbon composite negative electrode material, preparation method thereof and lithium ion battery
CN112259737A (en) * 2020-10-27 2021-01-22 成都新柯力化工科技有限公司 Preparation method of mesoporous spherical silicon oxide negative electrode material of lithium battery
CN112421018A (en) * 2020-11-30 2021-02-26 成都新柯力化工科技有限公司 Lithium battery porous silicon-oxygen-carbon negative electrode material for inhibiting volume expansion and preparation method thereof
CN113023738A (en) * 2021-03-03 2021-06-25 昆山宝创新能源科技有限公司 Silicon-based composite material, preparation method thereof and battery

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105826527A (en) * 2016-03-22 2016-08-03 浙江大学 Porous silicon-carbon composite material and preparation method and application thereof
CN106025220A (en) * 2016-06-24 2016-10-12 中天储能科技有限公司 Silicon oxide-based silicon-oxygen-carbon composite material and preparation method and application thereof
CN108539173A (en) * 2018-04-20 2018-09-14 中国科学院理化技术研究所 A kind of preparation method of graphene coated silicon composite
CN112018334A (en) * 2019-05-28 2020-12-01 贝特瑞新材料集团股份有限公司 Silicon oxide/carbon composite negative electrode material, preparation method thereof and lithium ion battery
CN111115639A (en) * 2019-12-25 2020-05-08 湖北万润新能源科技发展有限公司 Preparation of SiO by centering reactionxMethod and application of @ C material
CN111313029A (en) * 2020-02-28 2020-06-19 湖南农业大学 Closely-combined high-performance silicon/graphitized carbon composite material with hollow structure and preparation method and application thereof
CN111342014A (en) * 2020-03-05 2020-06-26 上海电气集团股份有限公司 Silicon-carbon negative electrode material of lithium ion battery and preparation method thereof
CN112259737A (en) * 2020-10-27 2021-01-22 成都新柯力化工科技有限公司 Preparation method of mesoporous spherical silicon oxide negative electrode material of lithium battery
CN112421018A (en) * 2020-11-30 2021-02-26 成都新柯力化工科技有限公司 Lithium battery porous silicon-oxygen-carbon negative electrode material for inhibiting volume expansion and preparation method thereof
CN113023738A (en) * 2021-03-03 2021-06-25 昆山宝创新能源科技有限公司 Silicon-based composite material, preparation method thereof and battery

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
冯运超: "二氧化碳中镁颗粒点火与燃烧过程研究", 《中国优秀硕士学位论文数据库 工程科技Ⅱ辑》 *

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