CN110556519A - Silicon cathode material, silicon cathode and preparation method of silicon cathode - Google Patents
Silicon cathode material, silicon cathode and preparation method of silicon cathode Download PDFInfo
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- H01M4/13—Electrodes for accumulators with non-aqueous electrolyte, e.g. for lithium-accumulators; Processes of manufacture thereof
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Abstract
The invention relates to the technical field of batteries and discloses a silicon cathode material, a silicon cathode and a preparation method of the silicon cathode, wherein the silicon cathode material comprises silicon particles, porous carbon and carbonized polyacrylonitrile, the silicon particles are attached to the hole wall of the porous carbon, and the carbonized polyacrylonitrile coats the silicon particles; meanwhile, in the silicon cathode material, the silicon particles are coated by the silicon carbide polyacrylonitrile, so that a strong acting force is generated between nitrogen atoms in the silicon carbide polyacrylonitrile and the silicon particles, a stable conductive network is formed, the silicon particles are prevented from damaging the overall structure of the silicon cathode due to volume expansion in the charging and discharging processes of the silicon cathode, and the cycle performance of the battery is finally improved.
Description
Technical Field
The invention relates to the technical field of batteries, in particular to a silicon cathode material, a silicon cathode and a preparation method of the silicon cathode.
Background
At present, the theoretical gram capacity of a traditional graphite cathode is about 372mAh/g, and the theoretical gram capacity of a silicon cathode is about 4200mAh/g, so that the addition of a small amount of silicon material in the traditional cathode material is a necessary trend for battery manufacturers to increase the gram capacity of the cathode. However, in the charging and discharging processes of the negative electrode added with the silicon material, the overall structure of the negative electrode is damaged due to the excessive volume expansion of the silicon particles, and finally, the cycle performance of the battery is poor.
Disclosure of Invention
The invention aims to provide a silicon cathode material, a silicon cathode and a preparation method of the silicon cathode, which can effectively relieve the volume expansion of silicon particles in the charge and discharge processes of the silicon cathode so as to avoid damaging the integral structure of the silicon cathode and improve the cycle performance of a battery.
in order to solve the technical problem, the invention provides a silicon anode material which comprises silicon particles, porous carbon and carbonized polyacrylonitrile, wherein the silicon particles are attached to the hole wall of the porous carbon, and the carbonized polyacrylonitrile coats the silicon particles.
preferably, the silicon anode material comprises 20-80 wt% of silicon particles, 5-50 wt% of porous carbon and 5-50 wt% of carbonized polyacrylonitrile based on the total weight of the silicon anode material.
preferably, the particle size of the silicon particles is 10nm to 1 um.
In order to solve the same technical problem, the invention also provides a silicon negative electrode, which comprises a copper foil and the silicon negative electrode material, wherein the silicon negative electrode material is attached to the copper foil.
in the silicon cathode material, because the silicon particles are attached to the hole wall of the porous carbon, the porous carbon can provide enough buffer space for the volume expansion of the silicon particles in the charge and discharge processes of the silicon cathode, so that the damage to the integral structure of the silicon cathode is avoided, and the cycle performance of a battery is improved; meanwhile, in the silicon cathode material, the silicon particles are coated by the silicon carbide polyacrylonitrile, so that a strong acting force is generated between nitrogen atoms in the silicon carbide polyacrylonitrile and the silicon particles, a stable conductive network is formed, the silicon particles are prevented from damaging the overall structure of the silicon cathode due to volume expansion in the charging and discharging processes of the silicon cathode, and the cycle performance of the battery is finally improved. In addition, the porous carbon has good conductivity, and the nitrogen atoms in the polyacrylonitrile carbide and the silicon particles can form a stable conductive network, so that the conductivity of the silicon cathode is improved, and the high-gram capacity performance of the silicon particles is fully exerted. In addition, the porous carbon can provide gram capacity for the silicon negative electrode, so that the capacity of the battery is increased, the energy density of the battery is improved, and the porous carbon has a large specific surface area, so that the porous carbon can provide a wetting site for the electrolyte in the silicon negative electrode.
In order to solve the same technical problem, the invention also provides a preparation method of the silicon cathode, which comprises the following steps:
Mixing silicon particles, porous carbon and polyacrylonitrile to obtain slurry;
Coating the slurry on a copper foil to obtain a pole piece;
drying the pole piece;
and in an inert gas atmosphere, carrying out heat treatment on the dried pole piece under a preset heat treatment condition to obtain the silicon negative electrode.
as a preferred scheme, the silicon particle porous carbon and polyacrylonitrile are mixed to obtain slurry, which specifically comprises the following steps:
mixing 20-80 wt% of silicon particles, 5-50 wt% of porous carbon and 5-50 wt% of polyacrylonitrile based on the total weight of the silicon particles, the porous carbon and the polyacrylonitrile to obtain slurry.
As a preferred scheme, the mixing of the silicon particle porous carbon and polyacrylonitrile to obtain the slurry specifically comprises:
carrying out ball milling dry mixing on silicon particles and porous carbon;
And mechanically stirring the dry-mixed silicon particles, the porous carbon and the polyacrylonitrile solution to obtain slurry.
preferably, the mass fraction of the polyacrylonitrile solution is 3% -10%.
Preferably, the step of coating the slurry on a copper foil to obtain the pole piece is to coat the slurry on the copper foil to obtain the pole piece with the coating loading capacity of silicon particles and porous carbon being 1-3mg/cm 2.
Preferably, the preset heat treatment conditions include: the heating rate is 2-10 ℃/min, the heat treatment temperature is 300-.
Preferably, the particle size of the silicon particles is 10nm to 1 um.
The invention provides a preparation method of a silicon negative electrode, which comprises the steps of mixing silicon particles, porous carbon and polyacrylonitrile to obtain slurry, coating the slurry on copper foil to obtain a pole piece, drying the pole piece, and finally carrying out heat treatment on the dried pole piece under preset heat treatment conditions in an inert gas atmosphere to obtain the silicon negative electrode, wherein in the obtained silicon negative electrode, the silicon particles are attached to the hole wall of the porous carbon, so that the porous carbon can provide enough buffer space for the volume expansion of the silicon particles in the charging and discharging processes of the silicon negative electrode, thereby avoiding damaging the integral structure of the silicon negative electrode and further improving the cycle performance of a battery; meanwhile, in the silicon cathode, the silicon particles are coated by the silicon carbide polyacrylonitrile, so that a strong acting force is generated between nitrogen atoms in the silicon carbide polyacrylonitrile and the silicon particles, a stable conductive network is formed, the silicon particles are prevented from damaging the overall structure of the silicon cathode due to volume expansion in the charging and discharging processes of the silicon cathode, and the cycle performance of the battery is finally improved. In addition, the porous carbon has good conductivity, and the nitrogen atoms in the polyacrylonitrile carbide and the silicon particles can form a stable conductive network, so that the conductivity of the silicon cathode is improved, and the high-gram capacity performance of the silicon particles is fully exerted. In addition, the porous carbon can provide gram capacity for the silicon negative electrode, so that the capacity of the battery is increased, the energy density of the battery is improved, and the porous carbon has a large specific surface area, so that the porous carbon can provide a wetting site for the electrolyte in the silicon negative electrode.
Drawings
FIG. 1 is a scanning electron micrograph of a silicon negative electrode material in an example of the present invention;
Fig. 2 is a partially enlarged view at a in fig. 1;
FIG. 3 is a scanning electron micrograph of porous carbon in an example of the invention;
FIG. 4 is a scanning electron micrograph of a silicon negative electrode material in a comparative example of the present invention;
FIG. 5 is a graph showing charge and discharge characteristics of a silicon negative electrode in example one of the present invention and a silicon negative electrode in a comparative example;
FIG. 6 is an infrared test chart of polyacrylonitrile of a silicon cathode prepared at different heat treatment temperatures in the first embodiment of the present invention;
FIG. 7 is a graph showing the charge and discharge characteristics of silicon anodes fabricated at different heat treatment temperatures according to a first embodiment of the present invention;
fig. 8 is a flowchart of a method for manufacturing a silicon negative electrode according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Referring to fig. 1 and 2, a silicon anode material according to a preferred embodiment of the present invention includes silicon particles, porous carbon, and polyacrylonitrile carbide, the silicon particles are attached to pore walls of the porous carbon, and the polyacrylonitrile carbide coats the silicon particles; the carbonized polyacrylonitrile specifically refers to carbonized polyacrylonitrile.
In the embodiment of the invention, in order to ensure that the silicon anode has better cycling stability and capacity, the silicon anode material comprises 20-80 wt% of silicon particles, 5-50 wt% of porous carbon and 5-50 wt% of carbonized polyacrylonitrile based on the total weight of the silicon anode material. Since the more lithium ions are consumed in forming a solid electrolyte interface (SEI film) and are irreversible in the next cycle when the carbon content is excessive, the lower coulombic efficiency of the first turn of the silicon negative electrode is easily caused; secondly, because when the carbonization polyacrylonitrile is too much, the carbonization polyacrylonitrile of the silicon cathode wraps up the silicon particles too tightly, so that the silicon particles do not have enough buffer space when the volume of the silicon cathode expands in the charging and discharging processes of the silicon cathode, the silicon cathode is easy to pulverize, and the cycling stability of the silicon cathode is finally affected.
in the embodiment of the invention, in order to ensure that the prepared silicon negative electrode has better cycle performance, the particle size of the silicon particles in the embodiment is 10nm-1 um. Because the pulverization of the silicon negative electrode is too serious easily caused by large volume change in the charging and discharging process when the particle size of the silicon particles is larger, the prepared silicon negative electrode has better cycle performance by selecting the silicon particles with the particle size of 10nm-1 um.
In order to solve the same technical problem, an embodiment of the present invention further provides a silicon negative electrode, where the silicon negative electrode includes a copper foil and the silicon negative electrode material, and the silicon negative electrode material is attached to the copper foil.
In the silicon cathode material, because the silicon particles are attached to the hole wall of the porous carbon, the porous carbon can provide enough buffer space for the volume expansion of the silicon particles in the charging and discharging processes of the silicon cathode, so that the damage to the integral structure of the silicon cathode is avoided, and the cycle performance of a battery is improved; meanwhile, in the silicon cathode material, the silicon particles are coated by the silicon carbide polyacrylonitrile, so that a strong acting force is generated between nitrogen atoms in the silicon carbide polyacrylonitrile and the silicon particles, a stable conductive network is formed, the silicon particles are prevented from damaging the overall structure of the silicon cathode due to volume expansion in the charging and discharging processes of the silicon cathode, and the cycle performance of the battery is finally improved. In addition, the porous carbon has good conductivity, and the nitrogen atoms in the polyacrylonitrile carbide and the silicon particles can form a stable conductive network, so that the conductivity of the silicon cathode is improved, and the high-gram capacity performance of the silicon particles is fully exerted. In addition, the porous carbon can provide gram capacity for the silicon negative electrode, so that the capacity of the battery is increased, the energy density of the battery is improved, and the porous carbon has a large specific surface area, so that the porous carbon can provide a wetting site for the electrolyte in the silicon negative electrode.
referring to fig. 8, in order to solve the same technical problem, an embodiment of the present invention further provides a method for manufacturing a silicon negative electrode, including the following steps:
s11, mixing the silicon particles, the porous carbon and the polyacrylonitrile to obtain slurry;
S12, coating the slurry on a copper foil to obtain a pole piece;
s13, drying the pole piece;
And S14, carrying out heat treatment on the dried pole piece under a preset heat treatment condition in an inert gas atmosphere to obtain the silicon negative electrode.
In the embodiment of the invention, the silicon particle porous carbon and the polyacrylonitrile solution are mixed to obtain the slurry, which specifically comprises the following steps:
Mixing 20-80 wt% of silicon particles, 5-50 wt% of porous carbon and 5-50 wt% of polyacrylonitrile based on the total weight of the silicon particles, the porous carbon and the polyacrylonitrile to obtain slurry.
In the embodiment of the present invention, in order to uniformly mix silicon particles, porous carbon, and polyacrylonitrile in the slurry, the mixing of the porous carbon of the silicon particles and the polyacrylonitrile in the embodiment to obtain the slurry specifically includes:
Carrying out ball milling dry mixing on silicon particles and porous carbon;
And mechanically stirring the dry-mixed silicon particles, the porous carbon and the polyacrylonitrile solution to obtain slurry.
in the embodiment of the invention, firstly, the silicon particles and the porous carbon are subjected to ball milling and dry mixing, and then the dry-mixed silicon particles, the dry-mixed porous carbon and the polyacrylonitrile solution are mechanically stirred, so that the silicon particles, the porous carbon and the polyacrylonitrile in the slurry can be uniformly mixed, and the prepared silicon cathode has good cycling stability and gram volume.
In the embodiment of the invention, the mass fraction of the polyacrylonitrile solution is 3-10%.
referring to fig. 3, in order to obtain porous carbon for preparing a silicon anode material, before performing ball milling dry mixing on silicon particles and the porous carbon, the method in this embodiment further includes the following steps: preparing porous carbon.
Wherein, the preparation of porous carbon specifically comprises:
Crushing the resin;
mixing the crushed resin with a catalyst to obtain a first product;
Mixing the first product with a strong base to obtain a second product;
drying the second product;
calcining the dried second product at 800 ℃ to obtain a third product;
Cleaning the third product with clear water and performing suction filtration until the pH value is 7;
And drying the third product after suction filtration to obtain the porous carbon.
In the embodiment of the invention, in order to ensure that the prepared silicon negative electrode has better cycle performance and gram capacity, the slurry is coated on a copper foil to obtain a pole piece, wherein the coating capacity of silicon particles and porous carbon is 1-3mg/cm 2, and the coating capacity of the silicon particles and the porous carbon represents the total mass of the silicon particles and the porous carbon coated on a unit area of the pole piece.
in the embodiment of the present invention, in order to prevent the pole piece coated with the slurry from being oxidized during drying, the drying of the pole piece in the embodiment specifically includes: and drying the pole piece under the vacuum condition of 80-150 ℃. The pole piece is dried under the vacuum condition, so that the pole piece coated with the slurry is prevented from being oxidized during drying, and the prepared silicon negative electrode is ensured to have good cycling stability and gram capacity.
In the embodiment of the present invention, in order to ensure that the silicon anode obtained after the heat treatment has good cycle performance and gram capacity, the preset heat treatment conditions in the embodiment include: the heating rate is 2-10 ℃/min, the heat treatment temperature is 300-. Because the polyacrylonitrile starts to carry out dehydration cyclization reaction under the condition of more than 300 ℃, and the polyacrylonitrile can be carbonized by continuously increasing the temperature, the heat treatment temperature is set to be 300-600 ℃ so as to improve the conductivity of the silicon cathode. In addition, the longer the heat preservation time at a higher temperature is, the smaller the binding force between the silicon negative electrode material and the copper foil is, so that the silicon negative electrode material is easy to fall off in the circulating process, and therefore, the heat preservation time is 10min-3h, the silicon negative electrode material is ensured not to fall off from the copper foil easily, and the silicon negative electrode obtained after heat treatment has good circulating performance and gram capacity.
in the embodiment of the present invention, the inert gas atmosphere is preferably a nitrogen atmosphere or an argon atmosphere. Certainly, the inert gas atmosphere is not limited to nitrogen atmosphere or argon atmosphere, and only needs to satisfy it and can avoid the pole piece is oxidized when drying, and does not do more and give unnecessary details here.
in the embodiment of the present invention, the particle size of the silicon particles in the present embodiment is preferably 10nm to 1 um.
The embodiment of the invention provides a preparation method of a silicon negative electrode, which comprises the steps of mixing silicon particles, porous carbon and polyacrylonitrile to obtain slurry, coating the slurry on copper foil to obtain a pole piece, drying the pole piece, and finally carrying out heat treatment on the dried pole piece under preset heat treatment conditions in an inert gas atmosphere to obtain the silicon negative electrode, wherein in the obtained silicon negative electrode, the porous carbon can provide enough buffer space for volume expansion of the silicon particles in the charging and discharging processes of the silicon negative electrode due to the fact that the silicon particles are attached to the hole wall of the porous carbon, so that the integral structure of the silicon negative electrode is prevented from being damaged, and the cycle performance of a battery is improved; meanwhile, in the silicon cathode, the silicon particles are coated by the silicon carbide polyacrylonitrile, so that a strong acting force is generated between nitrogen atoms in the silicon carbide polyacrylonitrile and the silicon particles, a stable conductive network is formed, the silicon particles are prevented from damaging the overall structure of the silicon cathode due to volume expansion in the charging and discharging processes of the silicon cathode, and the cycle performance of the battery is finally improved. In addition, the porous carbon has good conductivity, and the nitrogen atoms in the polyacrylonitrile carbide and the silicon particles can form a stable conductive network, so that the conductivity of the silicon cathode is improved, and the high-gram capacity performance of the silicon particles is fully exerted. In addition, the porous carbon can provide gram capacity for the silicon negative electrode, so that the capacity of the battery is increased, the energy density of the battery is improved, and the porous carbon has a large specific surface area, so that the porous carbon can provide a wetting site for the electrolyte in the silicon negative electrode.
the following examples are provided to illustrate the preparation of silicon anodes, and are specifically provided below:
example one
S21, carrying out ball milling dry mixing on the silicon particles and the porous carbon;
S22, mechanically stirring the dry-mixed silicon particles, the porous carbon and the polyacrylonitrile solution to obtain slurry; wherein, based on the total weight of the silicon particles, the porous carbon and the polyacrylonitrile, the content of the silicon particles accounts for 50 percent, the content of the porous carbon accounts for 20 percent, and the content of the polyacrylonitrile accounts for 30 percent; the mass fraction of the polyacrylonitrile solution is 5%; the particle size of the silicon particles is 50 nm;
S23, coating the slurry on a copper foil to obtain a pole piece with the coating loading of silicon particles and porous carbon being 1mg/cm 2;
s24, drying the pole piece under the vacuum condition of 80 ℃;
S25, carrying out heat treatment on the dried pole piece under a preset heat treatment condition in a nitrogen atmosphere to obtain the silicon negative electrode, wherein the preset heat treatment condition specifically comprises: the heating rate is 5 ℃/min, the heat treatment temperature is 450 ℃, and the heat preservation time is 10 min;
S26, cutting the obtained silicon cathode into a silicon cathode Si-Carbon-PAN with the diameter of 12 mm;
S27, assembling the silicon cathode Si-Carbon-PAN to obtain a button cell; and taking the silicon cathode Si-Carbon-PAN as the cathode of the button cell, taking the metal lithium as the anode of the button cell, and taking the lithium hexafluorophosphate as the electrolyte of the button cell.
S28, testing the button cell under preset test conditions; wherein, the preset test conditions specifically include: the test interval is 0.05V-1.5V, and the test current density is 1A/g;
wherein the silicon particles have a particle size of 40 nm.
Comparative example to example one:
s31, mechanically stirring the silicon particles and the polyacrylonitrile solution to obtain slurry; wherein, based on the total weight of the silicon particles and the polyacrylonitrile, the content of the silicon particles accounts for 70 percent, and the content of the polyacrylonitrile accounts for 30 percent; the mass fraction of the polyacrylonitrile solution is 5%; the particle size of the silicon particles is 50 nm;
S32, coating the slurry on a copper foil to obtain a pole piece with the coating load of silicon particles being 1mg/cm 2;
S33, drying the pole piece under the vacuum condition of 80 ℃;
S34, carrying out heat treatment on the dried pole piece under a preset heat treatment condition in a nitrogen atmosphere to obtain the silicon negative electrode, wherein the preset heat treatment condition specifically comprises: the heating rate is 5 ℃/min, the heat treatment temperature is 450 ℃, and the heat preservation time is 10 min;
s35, cutting the obtained silicon cathode into a silicon cathode Si-PAN with the diameter of 12 mm;
S36, assembling the silicon cathode Si-PAN to obtain a button cell; and taking the silicon negative electrode Si-PAN as a negative electrode of the button cell, taking metal lithium as a positive electrode of the button cell, and taking lithium hexafluorophosphate as an electrolyte of the button cell.
s37, testing the button cell under preset test conditions; wherein, the preset test conditions specifically include: the test interval is 0.05V-1.5V, and the test current density is 1A/g;
The particle size of the silicon particles is 40nm, and the coating load of the silicon particles represents the mass of the silicon particles coated on a unit area of the pole piece.
as shown in fig. 1, fig. 2 and fig. 4, the silicon particles in the first example are attached to porous Carbon, and the silicon particles are partially coated with carbonized polyacrylonitrile, so that when the silicon particles in the first example undergo volume expansion during charging and discharging of the Si-Carbon-PAN of the silicon anode, the silicon particles have a larger buffer space, thereby avoiding damage to the overall structure of the Si-Carbon-PAN of the silicon anode in the first example, and further improving the cycle performance of the battery; the silicon particles in the comparative example are lack of buffer space when the carbonized polyacrylonitrile is tightly coated on the silicon particles, so that the overall structure of the silicon anode Si-PAN in the comparative example is easy to damage.
in addition, as shown in fig. 5, in the case of a current density of 1A/g, the capacity retention rate of the button cell of the first example is higher than 90% in 300 cycles, and even after 300 cycles, the Si-Carbon-PAN of the silicon anode of the first example still has a gram capacity of 1300 mAh/g. In contrast, in the comparative example, the decrease in the gram capacity of the silicon negative electrode Si-PAN was very significant, and particularly after 300 revolutions, the silicon negative electrode Si-PAN hardly exhibited the capacity. It can be seen that, compared to the silicon negative electrode Si-PAN of the comparative example, since the silicon negative electrode Si-Carbon-PAN of the example one contains porous Carbon, the silicon negative electrode Si-Carbon-PAN has excellent conductivity and a robust overall structure, thereby having more excellent cycle performance and gram-capacity.
Effect of different Heat treatment temperatures on the Performance of silicon cathodes
in order to study the influence of different heat treatment temperatures on the performance of the silicon negative electrode, in the first embodiment of the present invention, by changing the heat treatment temperature, the performance of the silicon negative electrode obtained at different heat treatment temperatures (150 ℃, 250 ℃, 450 ℃, 600 ℃) is tested without changing other process steps and process parameters, and the test results are shown in fig. 6 and 7:
Referring to fig. 6, when the heat treatment temperature is 450 ℃, polyacrylonitrile is carbonized and part of cyano bonds (CN) are retained, and strong force is applied between cyano groups in the carbonized polyacrylonitrile and silicon particles, which is helpful for constructing a stable structure and achieving excellent cycle performance. In addition, as shown in fig. 7, the silicon negative electrode Si-Carbon-PAN-450 having the heat treatment temperature of 450 ℃ has more excellent cycle stability and capacity than the silicon negative electrode Si-Carbon-PAN-150 having the heat treatment temperature of 150 ℃. The initial capacity of the silicon cathode Si-Carbon-PAN-450 with the heat treatment temperature of 450 ℃ reaches 1250mAh/g, and the gram capacity of more than 1000mAh/g is still remained after the silicon cathode Si-Carbon-PAN-450 is circulated for 400 weeks; and the initial capacity of the silicon cathode Si-Carbon-PAN-150 with the heat treatment temperature of 150 ℃ is only 1000mAh/g, and the reduction range is large. Therefore, the polyacrylonitrile in the silicon cathode is carbonized at the heat treatment temperature of 450 ℃ and forms a complete conductive network under the combined action of the polyacrylonitrile and the porous carbon, so that the gram volume of silicon particles is favorably exerted. In addition, the cyano group in the carbonized polyacrylonitrile has stronger acting force with the silicon particles, so that a stable structure is favorably constructed, and the silicon cathode achieves excellent cycle performance.
effect of porous carbon of different mixing ratios on the performance of silicon cathode
In order to study the influence of porous carbon with different mixing ratios on the performance of the silicon negative electrode, in the embodiment of the invention, the mixing ratio of the porous carbon is changed, and on the premise that other process steps and process parameters are not changed, the performance of the silicon negative electrode obtained under the condition that the porous carbon with different mixing ratios (the weight ratios of the porous carbon are respectively 5%, 10%, 20%, 30%, 40% and 50% based on the total weight of the silicon particles, the porous carbon and the polyacrylonitrile, and correspondingly, the weight ratios of the silicon particles are respectively 75%, 70%, 60%, 50%, 40% and 30%) is tested.
and (4) test conclusion: the more porous carbon content, the lower the coulombic efficiency of the first turn of the silicon negative electrode, and in the following long cycle, although the silicon negative electrode can maintain the cycle stability, the capacity is lower. This is because the carbon content is too large, the more lithium ions are consumed in forming a solid electrolyte interface (SEI film), and it is irreversible in the next cycle.
Effect of incubation time for different thermal treatments on silicon negative Performance
In order to study the influence of the heat preservation time of different heat treatments on the performance of the silicon cathode, in the first embodiment of the invention, the performance of the silicon cathode obtained under the heat preservation time (10min, 30min, 1h, 2h and 3h) of different heat treatments is tested by changing the heat preservation time of the heat treatments under the premise that other process steps and process parameters are not changed.
And (4) test conclusion: the cycle performance of the silicon negative electrode is poorer as the holding time is longer, because the longer the holding time is at a higher temperature, the smaller the binding force between the silicon negative electrode material and the copper foil is, and the silicon negative electrode material is easy to fall off in the cycle process.
Effect of coating loadings of different silicon particles and porous carbon on silicon negative Performance
in order to study the influence of the coating loading amounts of different silicon particles and porous carbon on the performance of the silicon negative electrode, in the first embodiment of the invention, the performance of the silicon negative electrode obtained under the coating loading amounts of different silicon particles and porous carbon (1mg/cm 2, 1.5mg/cm 2, 2mg/cm 2, 2.5mg/cm 2 and 3mg/cm 2) is tested by changing the coating loading amounts of the silicon particles and the porous carbon under the premise of not changing other process steps and process parameters.
The test results show that the silicon negative electrode of the embodiment still shows better cycle performance when the loading of the silicon negative electrode is below 3mg/cm 2, and the gram capacity of 800mAh/g can be still maintained after 500 weeks of cycle, so that the silicon negative electrode of the embodiment has higher structural stability during the charge and discharge processes.
Effect of particle size of different silicon particles on the Performance of silicon cathodes
in order to study the influence of the particle sizes of different silicon particles on the performance of the silicon negative electrode, in the first embodiment of the present invention, the performance of the silicon negative electrode obtained under the particle sizes (10nm, 50nm, 150nm, 1um, 2um, 5um, and 10um) of different silicon particles is tested by changing the particle size of the silicon particles under the premise that other process steps and process parameters are not changed.
and (4) test conclusion: when the particle diameter of the silicon particles is below 1um, the prepared silicon negative electrode shows better cycle performance. When the particle size of the silicon particles is more than 1um, the prepared silicon negative electrode has poor cycle performance. This is because when the particle diameter of the silicon particles is 1um or more, the pulverization of the silicon negative electrode is relatively serious due to a large volume change during the charge and discharge, and therefore, it is preferable to use silicon particles having a particle diameter of 1um or less in the present invention.
Effect of Polyacrylonitrile in different mixing ratios on the Performance of silicon cathodes
in order to study the influence of polyacrylonitrile with different mixing ratios on the performance of the silicon cathode, in the first embodiment of the present invention, the performance of the silicon cathode obtained by polyacrylonitrile with different mixing ratios (the weight ratios of polyacrylonitrile are 5%, 15%, 25%, 35%, and 45% based on the total weight of silicon particles, porous carbon, and polyacrylonitrile) is tested by changing the mixing ratio of polyacrylonitrile and under the premise that other process steps and process parameters are not changed.
And (4) test conclusion: when the mixing proportion of polyacrylonitrile is below 25%, the silicon negative electrode can keep better cycling stability, and when the mixing proportion of polyacrylonitrile is higher, the cycling stability of the silicon negative electrode is poorer. The reason is that when the polyacrylonitrile is excessive, the silicon particles are wrapped by the silicon carbide polyacrylonitrile of the silicon cathode too tightly, so that the silicon particles do not have enough buffer space when volume expansion occurs in the charging and discharging processes of the silicon cathode, the silicon cathode is easy to pulverize, and the cycling stability of the silicon cathode is influenced finally.
To sum up, the embodiment of the invention provides a silicon negative electrode material, a silicon negative electrode and a preparation method of the silicon negative electrode, wherein the silicon negative electrode material is used for attaching silicon particles to the hole wall of porous carbon so as to ensure that the silicon particles can provide enough buffer space for the silicon particles when the silicon particles are subjected to volume expansion in the charging and discharging processes, so that the integral structure of the silicon negative electrode is prevented from being damaged, and the cycle performance of a battery is improved; meanwhile, the silicon particles are coated by the polyacrylonitrile, so that a strong acting force is generated between nitrogen atoms in the polyacrylonitrile and the silicon particles, a stable conductive network is formed, the damage to the overall structure of the silicon cathode caused by the volume expansion of the silicon particles in the charge and discharge processes of the silicon cathode is relieved, and the cycle performance of the battery is improved finally. In addition, because the silicon particles have poor conductivity, the embodiment of the invention improves the conductivity of the silicon cathode through the porous carbon with good conductivity and the stable conductive network formed by the nitrogen atoms in the polyacrylonitrile and the silicon particles, and is beneficial to the exertion of the high-gram capacity performance of the silicon particles. In addition, the porous carbon can provide gram capacity for the silicon cathode, so that the capacity of the battery is increased, the energy density of the battery is improved, and secondly, the porous carbon has a large specific surface area, so that a place can be provided for the electrolyte to infiltrate into the silicon cathode.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and substitutions can be made without departing from the technical principle of the present invention, and these modifications and substitutions should also be regarded as the protection scope of the present invention.
Claims (11)
1. The silicon anode material is characterized by comprising silicon particles, porous carbon and carbonized polyacrylonitrile, wherein the silicon particles are attached to the hole wall of the porous carbon, and the silicon particles are coated by the carbonized polyacrylonitrile.
2. The silicon anode material according to claim 1, wherein the silicon anode material comprises 20 to 80% by weight of silicon particles, 5 to 50% by weight of porous carbon, and 5 to 50% by weight of carbonized polyacrylonitrile, based on the total weight of the silicon anode material.
3. the silicon negative electrode material according to claim 1 or 2, wherein the silicon particles have a particle size of 10nm to 1 um.
4. A silicon negative electrode comprising a copper foil and the silicon negative electrode material according to any one of claims 1 to 3, wherein the silicon negative electrode material is adhered to the copper foil.
5. A preparation method of a silicon cathode is characterized by comprising the following steps:
mixing silicon particles, porous carbon and polyacrylonitrile to obtain slurry;
Coating the slurry on a copper foil to obtain a pole piece;
drying the pole piece;
And in an inert gas atmosphere, carrying out heat treatment on the dried pole piece under a preset heat treatment condition to obtain the silicon negative electrode.
6. The method for preparing the silicon negative electrode according to claim 5, wherein the silicon particles, the porous carbon and the polyacrylonitrile are mixed to obtain a slurry, specifically:
mixing 20-80 wt% of silicon particles, 5-50 wt% of porous carbon and 5-50 wt% of polyacrylonitrile based on the total weight of the silicon particles, the porous carbon and the polyacrylonitrile to obtain slurry.
7. The method for preparing the silicon negative electrode according to claim 5, wherein the mixing of the silicon particles, the porous carbon and the polyacrylonitrile to obtain the slurry specifically comprises:
carrying out ball milling dry mixing on silicon particles and porous carbon;
and mechanically stirring the dry-mixed silicon particles, the porous carbon and the polyacrylonitrile solution to obtain slurry.
8. The method for manufacturing a silicon negative electrode according to claim 7, wherein the mass fraction of the polyacrylonitrile solution is 3% to 10%.
9. the silicon negative electrode preparation method of any one of claims 5 to 8, wherein the slurry is coated on a copper foil to obtain a pole piece specifically:
And coating the slurry on a copper foil to obtain a pole piece with the coating loading of silicon particles and porous carbon being 1-3mg/cm 2.
10. the method for preparing a silicon negative electrode as claimed in any one of claims 5 to 8, wherein the predetermined heat treatment conditions include: the heating rate is 2-10 ℃/min, the heat treatment temperature is 300-.
11. The method of producing a silicon negative electrode as claimed in any of claims 5 to 8, wherein the silicon particles have a particle size of 10nm to 1 um.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111769269A (en) * | 2020-07-10 | 2020-10-13 | 黄杰 | Porous polymer nano-silicon composite anode material and preparation method and application thereof |
| WO2021017810A1 (en) * | 2019-07-29 | 2021-02-04 | 宁德时代新能源科技股份有限公司 | Negative electrode active material, preparation method therefor, secondary battery and battery module, battery pack and device associated therewith |
| WO2021017814A1 (en) * | 2019-07-29 | 2021-02-04 | 宁德时代新能源科技股份有限公司 | Negative electrode active material, preparation method therefor, secondary battery and battery module, battery pack and device associated therewith |
| CN113078318A (en) * | 2021-03-26 | 2021-07-06 | 广东凯金新能源科技股份有限公司 | Three-dimensional porous silicon-carbon composite material, preparation method and application thereof |
| CN114068901A (en) * | 2021-11-15 | 2022-02-18 | 陕西煤业化工技术研究院有限责任公司 | Silicon-carbon composite negative electrode material, preparation method and application |
| WO2022193123A1 (en) * | 2021-03-16 | 2022-09-22 | 宁德新能源科技有限公司 | Negative electrode material and preparation method therefor, electrochemical device, and electronic device |
| US11973215B2 (en) | 2019-07-29 | 2024-04-30 | Contemporary Amperex Technology Co., Limited | Negative active material, preparation method thereof, secondary battery and related battery module, battery pack and device |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102089240A (en) * | 2008-07-15 | 2011-06-08 | 杜伊斯堡-艾森大学 | Intercalation of silicon and/or tin into porous carbon substrates |
| CN102509781A (en) * | 2011-10-27 | 2012-06-20 | 上海交通大学 | Silicon-carbon composite anode material and preparing method thereof |
| CN102694155A (en) * | 2012-05-31 | 2012-09-26 | 奇瑞汽车股份有限公司 | Silicon-carbon composite material, preparation method thereof and lithium ion battery employing same |
| CN103840140A (en) * | 2012-11-21 | 2014-06-04 | 清华大学 | Porous carbon silicon composite material and preparation method thereof |
| CN105680023A (en) * | 2016-04-06 | 2016-06-15 | 上海璞泰来新能源科技股份有限公司 | Preparation method of composite high-magnification silicon-based material, cathode material and lithium battery |
| KR20170049968A (en) * | 2015-10-29 | 2017-05-11 | 한양대학교 산학협력단 | Electrode Material, Manufacturing Method Thereof and Secondary Battery Using the Same |
| WO2018095285A1 (en) * | 2016-11-23 | 2018-05-31 | Grst International Limited | Method of preparing anode slurry for secondary battery |
-
2018
- 2018-06-04 CN CN201810562921.5A patent/CN110556519A/en active Pending
- 2018-07-06 WO PCT/CN2018/094739 patent/WO2019232879A1/en active Application Filing
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102089240A (en) * | 2008-07-15 | 2011-06-08 | 杜伊斯堡-艾森大学 | Intercalation of silicon and/or tin into porous carbon substrates |
| CN102509781A (en) * | 2011-10-27 | 2012-06-20 | 上海交通大学 | Silicon-carbon composite anode material and preparing method thereof |
| CN102694155A (en) * | 2012-05-31 | 2012-09-26 | 奇瑞汽车股份有限公司 | Silicon-carbon composite material, preparation method thereof and lithium ion battery employing same |
| CN103840140A (en) * | 2012-11-21 | 2014-06-04 | 清华大学 | Porous carbon silicon composite material and preparation method thereof |
| KR20170049968A (en) * | 2015-10-29 | 2017-05-11 | 한양대학교 산학협력단 | Electrode Material, Manufacturing Method Thereof and Secondary Battery Using the Same |
| CN105680023A (en) * | 2016-04-06 | 2016-06-15 | 上海璞泰来新能源科技股份有限公司 | Preparation method of composite high-magnification silicon-based material, cathode material and lithium battery |
| WO2018095285A1 (en) * | 2016-11-23 | 2018-05-31 | Grst International Limited | Method of preparing anode slurry for secondary battery |
Non-Patent Citations (2)
| Title |
|---|
| DANIELA MOLINA PIPER, ET AL.: ""Conformal Coatings of Cyclized-Pan for Mechanically Resilient Si Nano-Composite Anodes"", 《ADVANCED ENERGY MATERIALS》 * |
| TAO CHEN, ET AL.: ""Low-temperature treated lignin as both binder and conductive additive for silicon nanoparticle composite electrodes in lithium-ion batteries"", 《ACS APPLIED MATERIALS & INTERFACES》 * |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2021017810A1 (en) * | 2019-07-29 | 2021-02-04 | 宁德时代新能源科技股份有限公司 | Negative electrode active material, preparation method therefor, secondary battery and battery module, battery pack and device associated therewith |
| WO2021017814A1 (en) * | 2019-07-29 | 2021-02-04 | 宁德时代新能源科技股份有限公司 | Negative electrode active material, preparation method therefor, secondary battery and battery module, battery pack and device associated therewith |
| EP3799164A4 (en) * | 2019-07-29 | 2021-08-25 | Contemporary Amperex Technology Co., Limited | Negative electrode active material, preparation method therefor, secondary battery and battery module, battery pack and device associated therewith |
| EP3799163A4 (en) * | 2019-07-29 | 2021-08-25 | Contemporary Amperex Technology Co., Limited | Negative electrode active material, preparation method therefor, secondary battery and battery module, battery pack and device associated therewith |
| US11973215B2 (en) | 2019-07-29 | 2024-04-30 | Contemporary Amperex Technology Co., Limited | Negative active material, preparation method thereof, secondary battery and related battery module, battery pack and device |
| CN111769269A (en) * | 2020-07-10 | 2020-10-13 | 黄杰 | Porous polymer nano-silicon composite anode material and preparation method and application thereof |
| WO2022193123A1 (en) * | 2021-03-16 | 2022-09-22 | 宁德新能源科技有限公司 | Negative electrode material and preparation method therefor, electrochemical device, and electronic device |
| CN113078318A (en) * | 2021-03-26 | 2021-07-06 | 广东凯金新能源科技股份有限公司 | Three-dimensional porous silicon-carbon composite material, preparation method and application thereof |
| CN113078318B (en) * | 2021-03-26 | 2023-08-08 | 广东凯金新能源科技股份有限公司 | Three-dimensional porous silicon-carbon composite material, preparation method and application thereof |
| US11894549B2 (en) | 2021-03-26 | 2024-02-06 | Guangdong Kaijin New Energy Technology Co., Ltd. | Three-dimensional porous silicon/carbon composite material, method for preparing same, and use thereof |
| CN114068901A (en) * | 2021-11-15 | 2022-02-18 | 陕西煤业化工技术研究院有限责任公司 | Silicon-carbon composite negative electrode material, preparation method and application |
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