CN113013399B - Preparation method and equipment of silicon-based negative electrode material - Google Patents
Preparation method and equipment of silicon-based negative electrode material Download PDFInfo
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Abstract
The application provides a preparation method and equipment of a silicon-based anode material, wherein the preparation method comprises the steps of evaporating an active substance at a first temperature and a specific pressure to obtain steam, wherein the active substance comprises silicon element; and condensing the steam to form a powder material in a non-oxidizing gas atmosphere with a specific inlet pressure at a second temperature, wherein the second temperature is lower than the first temperature. The silicon-based negative electrode material prepared by the preparation method and the equipment in the technical scheme has uniform particle size and controllable crystallization degree and mass percent of silicon, can realize continuous production of silicon-based negative electrode material powder, has low reaction energy consumption, and is beneficial to large-scale production of the silicon-based negative electrode material.
Description
Technical Field
The application relates to the field of lithium battery manufacturing, in particular to a preparation method and equipment of a silicon-based negative electrode material.
Background
Compared with graphite cathode materials, the silicon-based cathode material has higher specific capacity and is an important lithium ion battery cathode material. The preparation of the traditional silicon-based anode material roughly comprises two types: the first method is that steam of raw materials such as silicon, silicon dioxide and the like under the conditions of high temperature and vacuum is placed in a cooler for condensation to finally form a massive silicon-based anode material precursor, and then the steps of crushing, coating and the like are carried out to obtain a silicon-based anode material; and the other method is to grind the raw materials such as silicon, silicon dioxide and the like for a long time by adopting a high-energy ball mill to obtain a precursor of the powder silicon-based anode material, and then perform the steps of coating and the like to obtain the silicon-based anode material.
In actual production, however, the first preparation method is difficult to form continuous production, and meanwhile, because the silicon-based material has higher hardness and high energy consumption in the processing process, impurities are easy to introduce, and the requirement on equipment materials is also higher; the material obtained by the other preparation method is not uniform, the size of silicon particles in the product is large, and when the product is used for a lithium battery, the expansion degree is too large, and the cycle performance of the lithium battery is poor.
Disclosure of Invention
The application provides a preparation method and equipment of a silicon-based negative electrode material, the prepared silicon-based negative electrode material is uniform in particle size, controllable in crystallization degree and mass percent of silicon elements, continuous production of silicon-based negative electrode material powder can be realized, reaction energy consumption is low, and large-scale production of the silicon-based negative electrode material is facilitated.
One aspect of the present application provides a method for preparing a silicon-based anode material, including: evaporating an active substance at a first temperature and a specific pressure to obtain steam, wherein the active substance comprises silicon element; and condensing the steam to form a powder material in a non-oxidizing gas atmosphere with a specific inlet pressure at a second temperature, wherein the second temperature is lower than the first temperature.
In the embodiment of the application, the first temperature is 1000-2500 ℃, the specific pressure is 0.1-10000 Pa, the second temperature is 300-1100 ℃, and the specific air inlet pressure is 0.1-5 MPa.
In the embodiment of the application, when the active material is evaporated, non-oxidizing gas is also introduced, and the ratio of the gas inlet rate of the non-oxidizing gas to the evaporation rate of the active material is 1-100.
In an embodiment of the present application, the non-oxidizing gas includes at least one of an inert gas, hydrogen gas, and a carbon source gas.
In the embodiment of the present application, the non-oxidizing gas includes an inert gas and a carbon source gas, and the carbon source gas accounts for 0.1 to 50% by mass of the total mass of the non-oxidizing gas.
In an embodiment of the present application, the inert gas includes at least one of nitrogen, argon and helium, and the carbon source gas includes at least one of methane, ethane, ethylene, acetylene, ethanol, propane, butane, butene and pentane.
In the embodiment of the application, the mass of the silicon element is 39-100% of the total mass of the active substances, and the active substances comprise simple substance silicon and silicon oxide.
In an embodiment of the present application, the active material further includes a metal and a metal oxide.
In an embodiment of the present application, the powder material includes: SiOx, x is more than or equal to 0 and less than or equal to 1.6; MySiOz, y is more than or equal to 1 and less than or equal to 4, z is more than or equal to 2 and less than or equal to 6, and M is at least one of lithium and magnesium; wherein the mass of the SiOx is 50-100% of the total mass of the powder material, and the mass of the MySiOz is 0-50% of the total mass of the powder material.
In an embodiment of the present application, the powder material further includes: a carbon cladding layer that entirely or partially coats the SiOx and MySiOz.
The present application also provides an apparatus for preparing a silicon-based anode material, comprising: heating an evaporation device to evaporate the active substance at a first temperature and a specific pressure to obtain steam; a vacuum generating device comprising: a venturi chamber comprising communicating reduced cross-section, constant cross-section, and increased cross-section regions; a first gas inlet at one end of the reduced cross-section area for introducing a non-oxidizing gas having a specific inlet pressure; a second gas inlet, located in the area of reduced cross section or the area of constant cross section, communicating with the heating and evaporating device, for introducing the steam, and having a second temperature, lower than the first temperature, for condensing the steam to form a powdery material; and the discharge hole is positioned at one end of the section increasing area and is used for outputting the non-oxidizing gas and the powdery material.
In an embodiment of the present application, the apparatus for preparing a silicon-based anode material further includes: and the collecting device is connected with the discharge hole and is used for collecting the non-oxidizing gas and the powdery material.
In an embodiment of the present application, the apparatus for preparing a silicon-based anode material further includes: and one end of the gas path circulating device is connected with the first gas inlet, and the other end of the gas path circulating device is connected with the collecting device.
In an embodiment of the present application, the apparatus for preparing a silicon-based anode material further includes: and the gas pressurizing and preheating device is used for preheating and pressurizing the recycled non-oxidizing gas.
In the embodiment of the application, the heating mode of the heating evaporation device is medium-frequency induction heating or silicon-molybdenum rod heating, and the collecting device comprises at least one of a filtering collector and a cyclone collector.
In an embodiment of the present application, the apparatus for preparing a silicon-based anode material further includes: and the feeding device is connected with the heating evaporation device.
In the embodiment of the application, the heating evaporation device or the end of the feeding device is provided with a gas inlet for introducing inert gas into the heating evaporation device, and the ratio of the gas inlet rate of the inert gas to the evaporation rate of the active substance in the heating evaporation device is 1-100.
Compared with the prior art, the preparation method and the equipment in the technical scheme have the advantages that when the silicon-based negative electrode material is prepared, the process is simple, the control is easy, the energy consumption is low, and the continuous production can be carried out, so that the preparation method and the equipment are very suitable for large-scale production, and meanwhile, the particle size, the crystallization degree and the mass percentage of silicon elements of the silicon-based negative electrode material can be flexibly controlled.
Drawings
The following drawings describe in detail exemplary embodiments disclosed in the present application. Wherein like reference numerals refer to similar structures throughout the several views of the drawings. Those of ordinary skill in the art will understand that the present embodiments are non-limiting, exemplary embodiments and that the accompanying drawings are for illustrative and descriptive purposes only and are not intended to limit the scope of the present application, as other embodiments may equally fulfill the inventive intent of the present application. It should be understood that the figures are not drawn to scale. Wherein:
fig. 1 is a schematic flow chart of a method for preparing a silicon-based anode material according to an embodiment of the present application;
fig. 2 is a schematic structural diagram of an apparatus for preparing a silicon-based anode material according to an embodiment of the present application;
FIG. 3 is a cross-sectional view of a venturi chamber according to an embodiment of the present application;
fig. 4 is a schematic structural diagram of another apparatus for preparing a silicon-based anode material according to an embodiment of the present application.
Detailed Description
The following description is presented to enable any person skilled in the art to make and use the present disclosure, and is provided in the context of a particular application and its requirements. Various modifications to the disclosed embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the present application. Thus, the present application is not limited to the embodiments shown, but is to be accorded the widest scope consistent with the claims.
The technical solution of the present application will be described in detail below with reference to the embodiments and the accompanying drawings.
Referring to fig. 1, a method for preparing a silicon-based anode material according to an embodiment of the present application includes:
step S1: evaporating an active substance at a first temperature and a specific pressure to obtain a vapor, wherein the active substance comprises silicon element;
step S2: and condensing the steam to form a powder material in a non-oxidizing gas atmosphere with a specific inlet pressure at a second temperature, wherein the second temperature is lower than the first temperature.
In step S1, the first temperature and the specific pressure affect the silicon content (mass percentage of silicon element) in the final silicon-based anode material, and the first temperature and the specific pressure need to be controlled within a proper range, and the first temperature and the specific pressure are matched with each other to obtain the final ideal silicon content. In the embodiment of the application, the first temperature is 1000-2500 ℃, the first temperature is matched with the first temperature, and the specific pressure is 0.1-10000 Pa. For example, the first temperature may be 1000 ℃, 1100 ℃, 1200 ℃, 1300 ℃, 1400 ℃, 1500 ℃, 1600 ℃, 1700 ℃, 1800 ℃, 1900 ℃, 2000 ℃, 2100 ℃, 2200 ℃, 2300 ℃, 2400 ℃, 2500 ℃ or the like, and the specific pressure may be 0.1Pa, 0.5Pa, 1.0Pa, 2Pa, 4Pa, 6Pa, 8Pa, 10Pa, 20Pa, 50Pa, 70Pa, 100Pa, 300Pa, 500Pa, 700Pa, 1000Pa, 3000Pa, 5000Pa, 7000Pa, 10000Pa or the like. In some embodiments, when the mass percentage of the silicon element in the active material is 79%, for example, the active material includes silicon and silicon dioxide, and the silicon oxide with the mass percentage of 64% can be obtained under the conditions of 1500 ℃ and 10 Pa. In other embodiments, the active material comprises silicon and silicon dioxide, wherein the mass percent of silicon element is also 79%, and the silicon monoxide with the mass percent of silicon being 79% can be obtained under the conditions of 1800 ℃ and 50 Pa.
When the active substance is evaporated, non-oxidizing gas can be introduced to improve the evaporation and flow rate of the active substance so as to improve the production efficiency. The gas inlet rate of the non-oxidizing gas is very critical, the reaction time is not significantly influenced by the low gas inlet rate, the reaction time is prolonged instead of the vacuum degree which is easily reduced when the gas inlet rate is high, and therefore the gas inlet rate of the non-oxidizing gas is in a proper range to significantly shorten the whole reaction time. In the examples of the present application, the ratio of the intake rate of the non-oxidizing gas to the vaporization rate of the active material is 1 to 100.
The active material comprises silicon, the mass of the silicon is related to the first effect of the finally prepared silicon-based anode material, and when the mass of the silicon is too low, the first effect of the silicon-based anode material cannot meet the current requirements. The mass of the silicon element is 39-100% of the total mass of the active substances.
The active material comprises simple substance silicon and silicon oxide, wherein the general formula of the silicon oxide is SiOx (x is more than 0 and less than or equal to 2). The active material may further include a metal, which may include at least one of lithium and magnesium, and a metal oxide, which may include at least one of lithium oxide and magnesium oxide. When the active material only comprises silicon and silicon dioxide, the finally prepared silicon-based negative electrode material is a powder material comprising silicon monoxide; if the active material includes silicon, silicon dioxide, metal and metal oxide, in step S1, the metal reduces a part of the silicon dioxide to a simple substance of silicon at a first temperature, and the simple substance of silicon reacts with the silicon dioxide and the metal to generate metal silicate, and the finally prepared silicon-based negative electrode material is a powder material including the metal silicate and silica. The relative proportions of the components in the active substance are determined in accordance with the actual situation and are not particularly limited.
In step S2, at the second temperature and in the non-oxidizing atmosphere with the specific inlet pressure, the vapor formed in step S1 is condensed to form a powder material, which is the powdered silicon-based negative electrode material.
The second temperature is lower than the first temperature, so that the steam can be condensed into powder, and meanwhile, the crystallization degree of the finally formed silicon-based negative electrode material is obviously influenced by the size of the second temperature. If the second temperature is too high, the grain size of the formed silicon-based negative electrode material is larger; conversely, if the second temperature is too low, the steam condenses too quickly, which is detrimental to the collection of the device. In the embodiment of the application, the second temperature is 300 ℃ to 1100 ℃, and is matched with the range of the first temperature, so that the grain size of the formed silicon-based anode material is lower and more uniform. For example, the second temperature may be 300 ℃, 400 ℃, 500 ℃, 600 ℃, 700 ℃, 800 ℃, 850 ℃, 900 ℃, 950 ℃, 1000 ℃, 1050 ℃, 1100 ℃ or the like. In some embodiments, the exit temperature is 1000 ℃ and the grain size of the obtained silicon-based anode material is approximately 4.5 nm. In another embodiment, the outlet temperature is 300 ℃, and the obtained silicon-based anode material is in an amorphous structure.
The specific inlet pressure affects the particle size of the silicon-based anode material, and thus the non-oxidizing gas contacted by the vapor has the specific inlet pressure. This is because, on the one hand, the specific inlet pressure influences the degree of vacuum of the evaporation zone, which is the region in which the active substance evaporates; on the other hand, the specific inlet gas pressure can change the gas flow rate, so that the cooling time of the steam is changed, and the particle size of the silicon-based anode material is influenced under the combined action of the gas flow rate and the cooling time. The larger the specific inlet pressure is, the higher the vacuum degree of the evaporation area is, the smaller the particle size of the silicon-based anode material is, the specific inlet pressure is continuously increased to a certain degree, the influence on the particle size of the silicon-based anode material can be ignored, and the energy consumption is increased on the contrary, so that the specific inlet pressure needs to be controlled within a certain range. In the examples of the present application, the specific intake pressure is 0.1MPa to 5MPa, and for example, the specific intake pressure may be 0.1MPa, 0.2MPa, 0.5MPa, 1MPa, 2.5MPa, 3MPa, 3.5MPa, 4MPa, 4.5MPa, 5MPa, or the like. In some embodiments, the silicon-based anode material powder with an average particle size of 100nm can be obtained by mixing elemental silicon and silicon dioxide according to a proportion that the mass percentage of the silicon element is 50%, wherein the first temperature is 1600 ℃, the specific pressure is 10Pa, and the specific inlet pressure is set to 0.5 MPa. In another embodiment, the silicon-based negative electrode material powder with the average particle size of 50nm can be obtained by only setting the specific inlet pressure to 2MPa without changing other conditions.
The first temperature, the specific pressure, the second temperature and the specific air inlet pressure influence the particle size, the crystallization degree and the quality of the silicon-based negative electrode material together, so that the first temperature, the specific pressure, the second temperature and the specific air inlet pressure need to be matched with each other to achieve a better effect. Only one of the parameters is adjusted, the relevant performance parameters of the silicon-based anode material may be changed, but the performance of the silicon-based anode material cannot be adjusted to be optimal. In some embodiments, by mixing the simple substance of silicon and the silicon dioxide according to the mass percentage of the silicon element of 79%, so that the first temperature is 1650 ℃, the specific pressure is 10Pa, the second temperature is 500 ℃, and the specific air inlet pressure is 2Mpa, amorphous structure silica powder with the mass percentage of the silicon element of 65% and the average particle size of 50nm can be obtained. In some embodiments, by mixing the simple substance of silicon and the silicon dioxide according to the mass percentage of the silicon element of 79%, and making the first temperature be 1800 ℃, the specific pressure be 1Pa, the second temperature be 950 ℃, and the specific inlet pressure be 0.4Mpa, the silicon monoxide powder with the mass percentage of 79% and the average particle size of 200nm and with the silicon particle size of 4nm can be obtained.
The non-oxidizing gas may include at least one of an inert gas, hydrogen gas, and a carbon source gas. Wherein the inert gas may include at least one of nitrogen, argon, helium, and the carbon source gas may include at least one of methane, ethane, ethylene, acetylene, ethanol, propane, butane, butene, and pentane. And when the non-oxidizing gas only comprises a carbon source gas or comprises both the carbon source gas and an inert gas and/or hydrogen, the carbon source gas is subjected to reactions such as decomposition, polymerization and the like at the second temperature, and is deposited on the surface of powder when encountering the powder formed by condensing the steam, so that the prepared silicon-based negative electrode material is provided with the carbon coating layer. Therefore, the preparation method of the silicon-based anode material provided by the embodiment of the application is suitable for preparation of the silicon-based anode material with the carbon coating, is also suitable for preparation of the silicon-based anode material without the carbon coating, and has universality. The mass of the carbon source gas accounts for 0.1-50% of the total mass of the non-oxidizing gas, so that the formed carbon coating layer has a proper thickness and coating amount, and the concentration of the carbon source gas is in a proper range, so that the self-agglomeration phenomenon of the carbon source gas is reduced, and the carbon source gas can cover the surface of the powder to the maximum extent.
The powder material obtained by the preparation method of the silicon-based anode material in the embodiment of the application, namely the silicon-based anode material, comprises the following steps:
SiOx，0≤x≤1.6；
MySiOz, y is more than or equal to 1 and less than or equal to 4, z is more than or equal to 2 and less than or equal to 6, and M is at least one of lithium and magnesium;
wherein the mass of the SiOx is 50-100% of the total mass of the powder material, and the mass of the MySiOz is 0-50% of the total mass of the powder material.
In some embodiments, the powder material further comprises: a carbon cladding layer that entirely or partially coats the SiOx and MySiOz.
The average particle diameter of the powder material is 10nm-2000nm, and the mass percentage or volume percentage of particles with the sphericity of more than 0.90 is not less than 10%.
Correspondingly, the embodiment of the application also provides equipment for preparing the silicon-based anode material, and the silicon-based anode material is prepared according to the preparation method of the silicon-based anode material.
Referring to fig. 2, an apparatus for preparing a silicon-based anode material according to an embodiment of the present application includes: the evaporation apparatus 1 and the vacuum generation apparatus 2 are heated. In some embodiments, the apparatus may further comprise collecting means 3. Wherein the heating and evaporating device 1 is used for evaporating an active substance to obtain steam. That is, the heating and vaporizing device 1 is a place where the active material is vaporized, and the heating and vaporizing device 1 provides a first temperature and a specific pressure. The heating mode of the heating evaporation device 1 can be medium-frequency induction heating or silicon-molybdenum rod heating, and the material of the reaction crucible can be graphite or ceramic crucible, and is selected according to actual conditions.
With reference to fig. 2 and 3, the vacuum generator 2 has a venturi effect, and can provide negative pressure to the heating and evaporating device 1 to promote evaporation of the active material in the heating and evaporating device 1, and at the same time, the steam is directly ejected by the high-speed gas flow (i.e. the non-oxidizing gas), and the formed powder material is discharged from the vacuum generator 2 while the temperature is reduced. The vacuum generating device 2 comprises a venturi chamber 21, a first gas inlet 22, a second gas inlet 23 and a discharge hole 24, the venturi chamber 21 comprises a communicated section reduction area 21A, a section constant area 21B and a section increase area 22C, the first gas inlet 22 is positioned at one end of the section reduction area 21A and used for introducing non-oxidizing gas with specific air inlet pressure, and the second gas inlet 23 is positioned in the section reduction area 21A or the section constant area 21B and communicated with the heating and evaporating device 1 and used for introducing steam. In the present embodiment, the second gas inlet 23 is located in the constant cross-sectional area 21B. The second gas inlet 23 has a second temperature which is lower than the first temperature to effect condensation of the vapour which condenses to form a powdered material. The discharge port 24 is located at one end of the cross-section enlarging region 22C, and is used for discharging the non-oxidizing gas and the powdery material.
The collecting device 3 is connected with the discharge port 24 and used for collecting the non-oxidizing gas and the powdery material, and solid-gas separation can be realized, namely, the powdery material sinks to the bottom of the collecting device 3 due to gravity factors, and the non-oxidizing gas floats above the collecting device 3. The collecting means 3 comprises at least one of a filtering collector and a cyclone collector. In the embodiment of the present application, the collecting device 3 includes a filter collector and a cyclone collector to improve the collection rate of the powder material.
In some embodiments, the apparatus for preparing a silicon-based anode material further comprises a gas circulation device 4, wherein one end of the gas circulation device 4 is connected to the first gas inlet 22, and the other end is connected to the collection device 3. The gas circuit circulating device 4 comprises an input pipeline 41, an air pump 42 and an output pipeline 43 which are connected in sequence, wherein one end of the input pipeline 41 is connected with the collecting device 3, the other end of the input pipeline is connected with the air pump 42, one end of the output pipeline 43 is connected with the air pump 42, and the other end of the output pipeline is connected with the first gas inlet 22 of the vacuum generating device 2. The input pipe 41 transmits the non-oxidizing gas output by the collecting device 3 to the air pump 42, and the air pump 42 transmits the non-oxidizing gas to the first gas inlet 22 through the output pipe 43, so as to realize the recycling of the non-oxidizing gas. In some embodiments, a gas pressurization and preheating device 5 may be further added to preheat and pressurize the recycled non-oxidizing gas to make the temperature and the gas flow rate meet the requirements during use, and in some embodiments, the gas pressurization and preheating device 5 may be connected to the gas circuit circulating device 4.
Referring to fig. 4, the apparatus for preparing a silicon-based anode material may further include a feeding device 6, and the feeding device 6 is connected to the heating evaporation device 1, so that the apparatus may be continuously produced. In the embodiment of the present application, the feeding device 6 is fed at the bottom of the heating and evaporating device 1 to ensure that steam does not condense at the feeding portion, which would hinder the feeding.
In order to increase the evaporation capacity and the steam flow rate, an air inlet can be arranged at the end of the heating and evaporating device 1 or the feeding device 6 for introducing a non-oxidizing gas into the heating and evaporating device 1, and the ratio of the air inlet rate of the non-oxidizing gas to the evaporation rate of the active substance in the heating and evaporating device 1 is 1-100. Furthermore, the introduction of inert gas prevents the condensation of steam at the feed.
The working process of the equipment for preparing the silicon-based anode material is as follows: placing an active substance in the heating and evaporating device 1, enabling non-oxidizing gas to enter the Venturi chamber 21 through the first gas inlet 22 under a specific gas inlet pressure, adjusting the vacuum generating device 2 to enable the heating and evaporating device 1 to reach a specific pressure, raising the temperature in the heating and evaporating device 1 to a first temperature, and evaporating the active substance into steam; the steam enters the venturi chamber 21 of the vacuum generating device 2 through the second gas inlet 23 of the vacuum generating device 2, and the second gas inlet 23 has a second temperature, and the second temperature is lower than the first temperature, so that the steam is condensed into a powdery material. At the same time, the first gas inlet 22 of the vacuum generator 2 introduces a non-oxidizing gas with a specific inlet pressure into the venturi chamber 21, and the temperature of the non-oxidizing gas is lower than the first temperature, and the non-oxidizing gas can assist the steam condensation and carry the formed powder out of the vacuum generator 2. If the non-oxidizing gas also comprises a carbon source gas, a carbon coating layer is formed on the surface of the condensed powder; the powder material and the residual non-oxidizing gas outside the output vacuum generating device 2 enter a collecting device 3, the powder material sinks to the bottom of the collecting device 3 due to gravity factors, and the non-oxidizing gas floats above the collecting device 3; the gas circuit circulating device 4 pumps the non-oxidizing gas away from the collecting device 3 and conveys the non-oxidizing gas to the first gas inlet 22, so that the recycling of the non-oxidizing gas is realized.
The preparation method and the equipment of the silicon-based negative electrode material provided by the embodiment of the application realize the purposes of powdering and serialization of the product, and are favorable for reducing reaction energy consumption and realizing large-scale production of the silicon-based negative electrode material.
Example 1
The silicon-based negative electrode material is prepared by adopting equipment comprising a heating evaporation device, a vacuum generation device and a collection device, 10kg of elemental silicon and silicon dioxide are selected as active substances, the elemental silicon and the silicon dioxide are mixed according to the mass percent of silicon of 64 percent, a corundum crucible is used as a reaction container, medium-frequency induction heating is adopted, the collection device adopts a series connection mode of cyclone collection and filtration collection, and back-flushing airflow is arranged in a filter to prevent the filter from being blocked.
Firstly, setting the inlet pressure of non-oxidizing gas as 1MPa, wherein the non-oxidizing gas is argon, adjusting a vacuum generating device to pump the pressure in a heating and evaporating device to 1Pa, then raising the temperature in the heating and evaporating device to 1400 ℃, and setting the temperature at an inlet of a second gas as 300 ℃. After 10h, the heating was stopped, the mixture was cooled to room temperature under vacuum, and the vacuum generator was turned off, and the results are shown in Table 1.
Example 2
The temperature at the inlet of the second gas was adjusted to 1100 ℃ only, and the other results were the same as in example 1, and are shown in Table 1.
Example 3
The temperature in the heating and evaporating apparatus was adjusted to 1650 ℃ alone, and the results are shown in Table 1, except that the temperature in the heating and evaporating apparatus was changed to that in example 1.
Example 4
The mass percent of silicon was adjusted to 74%, the temperature in the heating and vaporizing apparatus was 1400 ℃, and the results are shown in table 1, except that the same was used as in example 1.
Example 5
The temperature in the heating and evaporating apparatus was adjusted to 1650 ℃, and the results are shown in table 1, except for the same as in example 4.
Example 6
The reaction vessel was changed to a graphite crucible, and the inlet pressure of the non-oxidizing gas was adjusted to 0.1MPa, the pressure of the heating and evaporating apparatus was adjusted to 1000Pa, and the temperature of the heating and evaporating apparatus was adjusted to 1700 ℃ in the same manner as in example 1, and the results are shown in Table 1.
Example 7
The same procedure as in example 1 was repeated except that the active material was silicon oxide SiOx (x is 1), and the results are shown in table 1.
TABLE 1 relevant parameters of silicon-based anode materials
Example 8
The silicon-based negative electrode material is prepared by adopting equipment comprising a heating evaporation device, a vacuum generation device and a collection device, 10kg of elemental silicon, silicon dioxide and magnesium are selected as active substances, the active substances are mixed according to the mass percent of 64 percent of silicon and 5 percent of magnesium, a graphite crucible is used as a reaction container, medium-frequency induction heating is adopted, the collection device adopts a cyclone collection and filtration collection series connection mode, back-flushing airflow is arranged in a filter, the filter is prevented from being blocked, and a gas preheating device is added.
Firstly, setting the air inlet pressure of argon to be 1MPa, adjusting a vacuum generating device to pump the pressure in a heating evaporation device to be 1Pa, and repeatedly replacing by using the argon to thoroughly remove the oxidizing atmosphere in the vacuum generating device. The temperature in the heating and evaporating unit was then raised to 1400 ℃ at a pressure of 10Pa and a temperature at the second gas inlet of 800 ℃. After 15h, the heating was stopped and the temperature was cooled to room temperature, and the results are shown in Table 2.
Example 9
The same procedures as in example 8 were repeated except that the active material was magnesium or a siliconoxide SiOx (x ═ 1), and the results are shown in table 2.
Example 10
The results are shown in table 2, except that simple substance magnesium and silica are used as active materials, and the mass fraction of the simple substance magnesium is 20%.
Example 11
The same procedure as in example 8 was repeated except that the raw materials were elemental magnesium and SiOx (x is 1) in which the mass percentage of elemental magnesium was 10%, the temperature of the heating and evaporation apparatus was adjusted to 1600 ℃, the pressure of the non-oxidizing gas fed was adjusted to 0.5MPa, and the pressure of the heating and evaporation apparatus was adjusted to 100Pa, and the results are shown in table 2.
Example 12
Argon and hydrogen (volume ratio 95: 5) were used as the non-oxidizing gas containing 5% methane, the temperature of the second gas inlet was set at 1000 ℃, otherwise the same as in example 11, and the product carbon content was measured at the discharge of 3%, other results are shown in table 2.
Table 2 relevant parameters of silicon-based anode materials
Example 13
The silicon-based negative electrode material is prepared by adopting equipment comprising a heating evaporation device, a vacuum generation device, a collection device and a gas circuit circulating device, 10kg of simple substance silicon is selected as an active substance and is placed in a graphite crucible, medium-frequency induction heating is adopted, and the collection device adopts a filtering and collecting mode.
Firstly, setting the air inlet pressure of argon to be 0.1MPa, adjusting a vacuum generating device to pump the pressure in a heating evaporation device to 1Pa, and repeatedly replacing by using argon to thoroughly remove the oxidizing atmosphere in the vacuum generating device. The temperature in the heating and evaporating device was then raised to 2450 ℃ at a pressure of 10000Pa and 800 ℃ at the second gas inlet. The feeding is continuously carried out in the whole process, wherein the material is fed from the bottom of the graphite crucible, and the feeding speed is 2 kg/h. 0.05L/min of argon was introduced simultaneously with the feed to increase the evaporation rate. The average grain size of the discharged material was 300nm, the grain size of silicon was 15nm, the silicon content was 100%, and other parameters are shown in Table 3.
Example 14
The pressure of the heating and evaporating apparatus was adjusted to 100Pa, the temperature at the second gas inlet was adjusted to 300 ℃ and the other conditions were the same as in example 13 to obtain a powder material having an average particle size of 2000nm, a discharge of amorphous silicon and a silicon content of 100%, and the other parameters are shown in Table 3.
Example 15
The inlet pressure was adjusted to 5MPa, no gas was introduced into the heating and evaporating apparatus during the reaction, the temperature at the second gas inlet was 900 ℃ and the other conditions were the same as in example 13, the average grain size of discharged material was 50nm, the silicon content was 100% and the other parameters are shown in Table 3.
Example 16
Argon as the non-oxidizing gas and 10% methane in the non-oxidizing gas, the temperature at the second gas inlet was set at 1000 ℃, otherwise the same as in example 13, the discharge average particle size was 300nm, the silicon grain size was 15nm, the silicon content was 95%, the carbon content was 5%, and other parameters are shown in table 3.
TABLE 3 parameters relating to silicon-based anode materials
In summary, the silicon-based negative electrode material prepared in each embodiment of the application is a powder material, each parameter index meets the requirement, the preparation process is simple and easy to control, the continuous production of the silicon-based negative electrode material powder can be realized, the reaction energy consumption is low, and the method is very suitable for large-scale production.
Finally, it should be understood that the embodiments of the application disclosed herein are illustrative of the principles of the embodiments of the present application. Other modified embodiments are also within the scope of the present application. Accordingly, the embodiments disclosed herein are to be considered in all respects as illustrative and not restrictive. Those skilled in the art may implement the present application in alternative configurations according to the embodiments of the present application. Thus, embodiments of the present application are not limited to those embodiments described with precision in the application.
Claims (15)
1. A preparation method of a silicon-based anode material is characterized by comprising the following steps:
evaporating active substances at a first temperature and a specific pressure to obtain steam, wherein the active substances comprise silicon elements, the first temperature is 1500-2500 ℃, the specific pressure is 0.1-10000 Pa, the mass of the silicon elements is 39-100% of the total mass of the active substances, and the active substances comprise elemental silicon and oxides of the silicon;
and condensing the steam to form a powder material in a non-oxidizing gas atmosphere with a specific inlet pressure at a second temperature, wherein the second temperature is lower than the first temperature, the second temperature is 300-1100 ℃, and the specific inlet pressure is 0.1-5 MPa.
2. The method for preparing the silicon-based anode material as claimed in claim 1, wherein a non-oxidizing gas is further introduced during the evaporation of the active material, and the ratio of the gas introduction rate of the non-oxidizing gas to the evaporation rate of the active material is 1 to 100.
3. The method of preparing a silicon-based anode material according to claim 1, wherein the non-oxidizing gas comprises at least one of an inert gas, hydrogen gas, and a carbon source gas.
4. The method for preparing the silicon-based anode material according to claim 3, wherein the non-oxidizing gas comprises an inert gas and a carbon source gas, and the mass of the carbon source gas accounts for 0.1-50% of the total mass of the non-oxidizing gas.
5. The method for preparing a silicon-based anode material according to claim 4, wherein the inert gas comprises at least one of nitrogen, argon and helium, and the carbon source gas comprises at least one of methane, ethane, ethylene, acetylene, ethanol, propane, butane, butene and pentane.
6. The method for preparing the silicon-based anode material as claimed in claim 1, wherein the active material further comprises a metal and a metal oxide.
7. The preparation method of the silicon-based anode material according to claim 1 or 6, wherein the powder material comprises:
SiOx，0≤x≤1.6；
MySiOz, y is more than or equal to 1 and less than or equal to 4, z is more than or equal to 2 and less than or equal to 6, and M is at least one of lithium and magnesium;
wherein the mass of the SiOx is 50-100% of the total mass of the powder material, and the mass of the MySiOz is 0-50% of the total mass of the powder material.
8. The method for preparing the silicon-based anode material according to claim 7, wherein the powder material further comprises: a carbon cladding layer that entirely or partially coats the SiOx and MySiOz.
9. An apparatus for preparing a silicon-based anode material, comprising:
heating an evaporation device to evaporate the active substance at a first temperature and a specific pressure to obtain steam;
a vacuum generating device comprising:
a venturi chamber comprising communicating reduced cross-section, constant cross-section, and increased cross-section regions;
a first gas inlet positioned at one end of the section reducing area and used for introducing non-oxidizing gas with specific inlet pressure;
a second gas inlet, located in the area with reduced cross section or the area with constant cross section, communicated with the heating and evaporating device, for introducing the steam, and having a second temperature lower than the first temperature, so that the steam is condensed to form a powdery material;
and the discharge hole is positioned at one end of the section increasing area and is used for outputting the non-oxidizing gas and the powdery material.
10. The apparatus for preparing silicon-based anode material according to claim 9, further comprising: and the collecting device is connected with the discharge hole and is used for collecting the non-oxidizing gas and the powdery material.
11. The apparatus for preparing silicon-based anode material according to claim 10, further comprising: and one end of the gas path circulating device is connected with the first gas inlet, and the other end of the gas path circulating device is connected with the collecting device.
12. The apparatus for preparing silicon-based anode material according to claim 11, further comprising: and the gas pressurizing and preheating device is used for preheating and pressurizing the recycled non-oxidizing gas.
13. The apparatus for preparing silicon-based anode material according to claim 10, wherein the heating evaporation device is heated by medium frequency induction heating or silicon molybdenum rod heating, and the collection device comprises at least one of a filter collector and a cyclone collector.
14. The apparatus for preparing silicon-based anode material according to claim 9, further comprising: and the feeding device is connected with the heating evaporation device.
15. The apparatus for preparing silicon-based anode material according to claim 14, wherein the heating evaporation apparatus or the end of the feeding apparatus has a gas inlet for introducing inert gas into the heating evaporation apparatus, and the ratio of the gas inlet rate of the inert gas to the evaporation rate of the active material in the heating evaporation apparatus is 1-100.
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106282967A (en) * | 2016-08-23 | 2017-01-04 | 深圳市国创新能源研究院 | A kind of equipment preparing SiO/C composite |
| CN108821292A (en) * | 2017-05-05 | 2018-11-16 | 储晞 | It is a kind of to produce the method and device for aoxidizing sub- silicon |
| CN110137446A (en) * | 2019-04-03 | 2019-08-16 | 兰溪致德新能源材料有限公司 | Nano-silicone wire/carbon negative electrode material process units and production technology |
| CN110615423A (en) * | 2019-09-24 | 2019-12-27 | 中国科学院化学研究所 | Preparation method of silicon-based composite negative electrode material of lithium battery |
| CN111816859A (en) * | 2020-07-22 | 2020-10-23 | 贝特瑞新材料集团股份有限公司 | Silicon-based negative electrode material, preparation method thereof and lithium ion secondary battery |
| CN112151767A (en) * | 2020-09-11 | 2020-12-29 | 成都新柯力化工科技有限公司 | Method for preparing lithium battery cathode by compounding silicon-carbon-silicon dioxide in extruder |
-
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Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106282967A (en) * | 2016-08-23 | 2017-01-04 | 深圳市国创新能源研究院 | A kind of equipment preparing SiO/C composite |
| CN108821292A (en) * | 2017-05-05 | 2018-11-16 | 储晞 | It is a kind of to produce the method and device for aoxidizing sub- silicon |
| CN110137446A (en) * | 2019-04-03 | 2019-08-16 | 兰溪致德新能源材料有限公司 | Nano-silicone wire/carbon negative electrode material process units and production technology |
| CN110615423A (en) * | 2019-09-24 | 2019-12-27 | 中国科学院化学研究所 | Preparation method of silicon-based composite negative electrode material of lithium battery |
| CN111816859A (en) * | 2020-07-22 | 2020-10-23 | 贝特瑞新材料集团股份有限公司 | Silicon-based negative electrode material, preparation method thereof and lithium ion secondary battery |
| CN112151767A (en) * | 2020-09-11 | 2020-12-29 | 成都新柯力化工科技有限公司 | Method for preparing lithium battery cathode by compounding silicon-carbon-silicon dioxide in extruder |
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