Patent Application
20250183255
The present application claims priority to and the benefit of Korean Patent Application No. 10-2023-0117867 filed on Sep. 5, 2023, in the Korean Intellectual Property Office, the entire disclosure of which is incorporated by reference herein.
Embodiments of the present disclosure relate to a manufacturing method of a dry electrode.
Generally, a rechargeable battery is a battery that can be repeatedly charged and discharged.
Recently, there is an increased interest in a method of manufacturing dry electrodes for rechargeable batteries that do not use solvents.
In an existing manufacturing method of a dry electrode, the dry electrode may be manufactured by fiberizing a mixture including an active material, a conductive material, and a binder to form a fiberized dry powder by using a kneading device, etc., calendering the fiberized dry powder to form a free-standing film by using a calendering roll, etc., and laminating the standing film to a current collector.
However, in the existing dry electrode manufacturing method, the length of the fiberized binder included in the dry powder is not uniform, so the dry powder does not have a predetermined particle size distribution, so there is a problem in that the thickness and width of the free-standing film manufactured by the calendering are not uniform.
An embodiment of the present disclosure provides a manufacturing method of a dry electrode in which dry electrode manufacturing efficiency is improved by uniform (or substantially uniform) thickness and width of the free-standing film manufactured by the calendering.
A manufacturing method of a dry electrode includes fiberizing a mixture including an active material, a conductive material, and a binder into a fiberized dry powder; first crushing and second crushing the fiberized dry powder into a minute powder; and calendering the minute powder into a free-standing film.
In the minute powder, a particle ratio of 45 μm to 1000 μm may be 94 wt % to 99 wt %.
In the minute powder, a particle ratio of less than 45 μm and greater than 1000 μm may be 1 wt % to 6 wt %.
In the minute powder, a particle ratio of 45 μm to 1000 μm may be 96 wt % to 98 wt %.
In the minute powder, a particle ratio of less than 45 μm and greater than 1000 μm may be 2 wt % to 4 wt %.
The active material may be 96 wt % to 98 wt % of the mixture, the conductive material may be 0.1 wt % to 2 wt % of the mixture, and the binder may be 1 wt % to 3 wt % of the mixture.
The active material may include a metal oxide, the conductive material may include carbon black, and the binder may include polytetrafluoroethylene (PTFE).
In the calendering of the minute powder into the free-standing film, the free-standing film may be formed into the free-standing film at a calendering speed of 15 m/min to 30 m/min.
The first crushing and the second crushing may be performed for a crushing time of 30 min/kg to 45 min/kg depending on the weight of the dry powder.
The first crushing may be performed for a crushing time of 10 min/kg to 15 min/kg depending on the weight of the dry powder.
The second crushing may be performed for a crushing time of 15 min/kg to 45 min/kg depending on the weight of the dry powder.
The crushing time of the second crushing may be 100% to 300% of the crushing time of the first crushing.
The crushing time of the second crushing may be the same as the crushing time of the first crushing.
Pressing the free-standing film and laminating the free-standing film to a current collector may be further included.
The calendering of the minute powder into the free-standing film may include pressing the free-standing film and laminating the free-standing film to a current collector.
According to an embodiment, the manufacturing method of the dry electrode having improved dry electrode manufacturing efficiency is provided by uniformly (or substantially uniformly) forming the thickness and the width of the free-standing film manufactured by the calendering.
The accompanying drawings, together with the specification, illustrate embodiments of the subject matter of the present disclosure, and, together with the description, serve to explain principles of embodiments of the subject matter of the present disclosure.
Embodiments of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments of the disclosure are shown. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present disclosure.
Unless explicitly described to the contrary, the word “comprise,” and variations such as “comprises” or “comprising,” will be understood to imply the inclusion of stated elements but not the exclusion of any other elements.
Hereinafter, a manufacturing method of a dry electrode according to an embodiment is described with reference to
The manufacturing method of the dry electrode according to an embodiment may be a method for manufacturing a dry electrode for a rechargeable battery, but is not limited thereto and may be any suitable method for manufacturing various suitable dry electrodes.
In some embodiments, each of a fiberizing method (e.g., a fibrillizing method), a crushing method, a calendering method, and a laminating method used in the manufacturing method of the dry electrode according to an embodiment may include various suitable methods.
Referring to
In some embodiments, the active material, the conductive material, and the binder are mixed together into a mixture by using various suitable mixing methods, and the mixture is fiberized (e.g., fibrillized) into a fiberized (e.g., fibrillized) dry powder by using various suitable fiberizing (e.g., fibrillizing) methods.
For example, the active material may be 96 wt % to 98 wt % of the mixture, the conductive material may be 0.1 wt % to 2 wt % of the mixture, and the binder may be 1 wt % to 3 wt % of the mixture, but it is not limited thereto. The active material may include a metal oxide (e.g., a metal oxide series), the conductive material may include carbon black, and the binder may include polytetrafluoroethylene (PTFE), but it is not limited thereto.
As another example, the active material included in the mixture may be 90 wt % to 99 wt % of the mixture, the conductive material may be 0.5 wt % to 9.5 wt % of the mixture, and the binder may be 0.5 wt % to 10 wt % of the mixture, but it is not limited thereto. The active material may include a variety of suitable electrode active materials including nickel cobalt aluminum (NCA), and the conductive material may include a variety of suitable conductive materials including at least one selected from Ketjenblack and carbon nanotubes, and the binder may include various suitable fiberizing binders including polytetrafluoroethylene (PTFE).
For example, the mixture may be fiberized into a fiberized dry powder by using a kneading device including a plurality of screws, but is not limited thereto and may be fiberized into a dry powder including a fiberized binder by using various suitable fiberizing methods.
In some embodiments, the dry powder is first ground (e.g., first crushing) and second ground (e.g., second crushing) into a minute powder (S200).
In some embodiments, the dry powder is first ground (Crushing 1) and then second ground (Crushing 2) by using a crushing methods. The first crushing (Crushing 1) and the second crushing (Crushing 2) may be performed using various suitable crushing methods, and may be performed using different crushing methods and/or the same crushing methods.
For example, the first crushing and the second crushing may each include a disintegration of the dry powder aggregated together by the fiberized binder into dispersed minute powders, but are not limited thereto.
For example, the first crushing and the second crushing may be performed for a crushing time of 30 min/kg to 45 min/kg depending on the weight of the dry powder supplied by the crushing methods, but it is not limited thereto. The first crushing may be performed for a crushing time of 10 min/kg to 15 min/kg depending on the weight of the dry powder. The second crushing may be performed for a crushing time of 15 min/kg to 45 min/kg depending on the weight of dry powder.
For example, the crushing time of the second crushing may be 100% to 300% of the crushing time of the first crushing. The crushing time of the second crushing may be the same as the crushing time of the first crushing.
For example, in the minute powder ground from the dry powder by the first crushing and the second crushing, a particle ratio of 45 μm to 1000 μm may be 94 wt % to 99 wt % of the minute powder (e.g., an amount of particles having a particle size of 45 μm to 1000 μm may be 94 wt % to 99 wt % based on 100 wt % of the minute powder). In the minute powder, a particle ratio of less than 45 μm and greater than 1000 μm may be 1 wt % to 6 wt % of the minute powder (e.g., a sum of an amount of particles having a particle size of less than 45 μm and an amount of particles having a particle size of greater than 1000 μm may be 1 wt % to 6 wt % based on 100 wt % of the minute powder).
As another example, in the minute powder ground from the dry powder by the first crushing and the second crushing, a particle ratio of 45 μm to 1000 μm may be 96 wt % to 98 wt % of the minute powder (e.g., an amount of particles having a particle size of 45 μm to 1000 μm may be 96 wt % to 98 wt % based on 100 wt % of the minute powder). In the minute powder, a particle ratio of less than 45 μm and greater than 1000 μm may be 2 wt % to 4 wt % of minute powder (e.g., a sum of an amount of particles having a particle size of less than 45 μm and an amount of particles having a particle size of greater than 1000 μm may be 2 wt % to 4 wt % based on 100 wt % of the minute powder).
In some embodiments, the minute powder is calendered into a free-standing film (S300).
In some embodiments, the minute powder is supplied to, for example, a calendering roll and calendered into the free-standing film.
For example, if calendering the minute powder into the free-standing film, the free-standing film may be formed at a film formation speed of 15 m/min to 30 m/min, but it is not limited thereto.
In some embodiments, the free-standing film is pressed.
In some embodiments, the free-standing film may be supplied to, for example, a pressing roll to press and stretch the free-standing film.
In some embodiments, the free-standing film is laminated onto a current collector.
In some embodiments, the pressed free-standing film may be supplied to, for example, a laminating roll together with a metal foil, which is a current collector, to laminate the free-standing film onto the current collector.
Referring to
In some embodiments, the dry powder is first ground and second ground into a minute powder.
In some embodiments, the minute powder is calendered into a free-standing film.
In some embodiments, the minute powder may be supplied to, for example, a multi-roll calendering device including, for example, a calendering roll, a pressing roll, and a laminating roll to calender the minute powder into the free-standing film, the free-standing film may be pressed, and the free-standing film may be laminated onto the current collector.
The dry electrode may be manufactured by the manufacturing method of the dry electrode described above.
In the manufacturing method of the dry electrode according to an embodiment, the fiberized dry powder is first ground and second ground into the minute powder, and the minute powder is calendered to the free-standing film, so that the length of the fiberized binder included in the dry powder is uniformly (or substantially uniformly) ground by the first crushing and the second crushing, and the minute powder ground from the dry powder has a set or predetermined particle size distribution, and accordingly the free-standing film having uniform (or substantially uniform) thickness and width may be manufactured by the calendering and concurrently (e.g., simultaneously) a film loss rate may be minimized or reduced during manufacturing of the free-standing film.
Also, in the manufacturing method of the dry electrode according to an embodiment, as the minute powder that is first ground and second ground from the fiberized dry powder includes a numerical limitation of the particle ratio of 45 μm to 1000 μm of 94 wt % to 99 wt % (e.g., an amount of particles having a particle size of 45 μm to 1000 μm being 94 wt % to 99 wt % based on 100 wt % of the minute powder) and the particle ratio of less than 45 μm and greater than 1000 μm of 1 wt % to 6 wt % (e.g., a sum of an amount of particles having a particle size of less than 45 μm and an amount of particles having a particle size of greater than 1000 μm being 1 wt % to 6 wt % based on 100 wt % of the minute powder), the minute powder ground from the dry powder has a set or predetermined particle size distribution, and accordingly the free-standing film having uniform (or substantially uniform) thickness and width may be manufactured by the calendering and concurrently (e.g., simultaneously) a loss rate of the minute powder and a loss rate of the free-standing film may be minimized or reduced during the free-standing film manufacturing.
Also, in the manufacturing method of the dry electrode according to an embodiment, as the minute powder that is first ground and second ground from the fiberized dry powder includes a configuration of a threshold significance of a numerical limitation of the particle ratio of 45 μm to 1000 μm of 96 wt % to 98 wt % (e.g., an amount of particles having a particle size of 45 μm to 1000 μm being 96 wt % to 98 wt % based on 100 wt % of the minute powder) and the particle ratio of less than 45 μm and greater than 1000 μm of 2 wt % to 4 wt % (e.g., a sum of an amount of particles having a particle size of less than 45 μm and an amount of particles having a particle size of greater than 1000 μm being 2 wt % to 4 wt % based on 100 wt % of the minute powder), the minute powder ground from the dry powder has a set or predetermined particle size distribution, and accordingly the free-standing film having uniform (or substantially uniform) thickness and width may be manufactured by the calendering and concurrently (e.g., simultaneously) a loss rate of the minute powder and a loss rate of the free-standing film may be minimized or reduced during the free-standing film manufacturing.
For example, the manufacturing method of the dry electrode that improves a dry electrode manufacturing efficiency by rendering the thickness and width of the free-standing film manufactured by the calendering uniform (or substantially uniform) is provided.
Hereinafter, experimental examples and comparative examples of confirming effects of the manufacturing method of the dry electrode according to an embodiment are described with reference to
Referring to
A mixture including 96 wt % to 98 wt % of an active material including a metal oxide, 0.1 wt % to 2 wt % of a conductive material including carbon black, and 1 wt % to 3 wt % of a binder including polytetrafluoroethylene (PTFE) was fiberized into a fiberized dry powder, the dry powder was first ground for a crushing time of 10 min/kg and second ground for a crushing time of 20 min/kg depending on the dry powder weight to form a minute powder. The minute powder was calendered at a film forming speed (a film calendering speed) of 15 m/min to form a free-standing film having a width of 210 mm. As an experimental result of experimental example 1 EX1, an average of a free-standing film thickness and a standard deviation, an average of a film loading level (a film L/L) and a standard deviation, and a film loss rate are the same as the table shown in
Experimental example 2 EX2, experimental example 3 EX3, and experimental example 4 EX4 are identical to experimental example 1 EX1 in all conditions except for the film formation speed (the film calendering speed). As an experimental result of experimental example 2 EX2, experimental example 3 EX3, and experimental example 4 EX4, the free-standing film thickness, the film loading level (film L/L), and the film loss rate are the same as in the table shown in
Experimental example 5 EX5 is identical to experimental example 1 EX1 in all conditions except that the minute powder is calendered into the free-standing by film using a multi roll calendering device. As an experimental result of experimental example 5 EX5, the free-standing film thickness, the film loading level (film L/L), and the film loss rate are the same as the table shown in
Experimental example 6 EX6, experimental example 7 EX7, and experimental example 8 EX8 are identical to experimental example 5 EX5 in all conditions except for the film formation speed (the film calendering speed). As an experimental result of experimental example 6 EX6, experimental example 7 EX7, and experimental example 8 EX8, the free-standing film thickness, the film loading level (film L/L), and the film loss rate are the same as in the table shown in
A mixture including 96 wt % to 98 wt % of an active material including a metal oxide, 0.1 wt % to 2 wt % of a conductive material including carbon black, and 1 wt % to 3 wt % of a binder including polytetrafluoroethylene (PTFE) was fiberized into a fiberized dry powder, and the dry powder was calendered at a film forming speed of 14 m/min to form a free-standing film having a width of 210 mm. As an experimental result of comparative example 1 CO1, the free-standing film thickness, the film loading level (film L/L), and the film loss rate are the same as in the table shown in
Comparative example 2 CO2 is the same as comparative example 1 CO1 in all conditions except for the film formation speed (the film calendering speed). Comparative example 3 CO3 is the same as comparative example 1 CO1 in all conditions except that the dry powder was calendered into the free-standing film by using a film formation speed (a film calendering speed) and a multi-roll calendering device. As an experimental result of comparative example 2 CO2 and comparative example 3 CO3, the free-standing film thickness, the film loading level (film L/L), and the film loss rate are the same as the table shown in
As the first experimental result of experimental example 1 EX1, experimental example 2 EX2, experimental example 3 EX3, experimental example 4 EX4, experimental example 5 EX5, experimental example 6 EX6, experimental example 7 EX7, and experimental example 8 EX8 described above, compared with comparative example 1 CO1, comparative example 2 CO2, and comparative example 3 CO3, it was confirmed that the free-standing film thickness and the film loading level (film L/L) are uniform, and the film loss rate is minimized or reduced in each of experimental example 1 EX1, experimental example 2 EX2, experimental example 3 EX3, experimental example 4 EX4, experimental example 5 EX5, experimental example 6 EX6, experimental example 7 EX7, and experimental example 8 EX8, in which the dry powder is first ground and second ground into the minute powder.
According to the first experimental result, in the manufacturing method of the dry electrode according to an embodiment, the fiberized dry powder is first ground and second ground into the minute powder, and the minute powder is calendered to the free-standing film, so that the length of the fiberized binder included in the dry powder is uniformly ground by the first crushing and the second crushing, and the minute powder ground from the dry powder has a set or predetermined particle size distribution, and accordingly the free-standing film having uniform (or substantially uniform) thickness and width may be manufactured by the calendering and concurrently (e.g., simultaneously) a loss rate of the film may be minimized or reduced during the free-standing film manufacturing.
Referring to
A mixture including 96 wt % to 98 wt % of an active material including a metal oxide, 0.1 wt % to 2 wt % of a conductive material including carbon black, and 1 wt % to 3 wt % of a binder including polytetrafluoroethylene (PTFE) was fiberized into a fiberized dry powder, and the dry powder is first ground (Crushing 1) for a crushing time of 15 min/kg, and second ground (Crushing 2) for a crushing time of 15 min/kg depending on the dry powder weight for a total crushing time of 30 min/kg to form a minute powder. The minute powder was calendered by using a multi-roll calendering device at a film calendering speed of 30 m/min to form a free-standing film of 210 mm width. As an experimental result of experimental example 9 EX9, a particle size distribution and a loss rate of the minute powder first ground and second ground from the dry powder are the same as in the table shown in
Experimental example 10 EX10, experimental example 11 EX11, and experimental example 12 EX12 are the same as experimental example 9 EX9 in all conditions except for the first crushing time and the second crushing time. In experimental example 10 EX10, the dry powder was first ground for a crushing time of 15 min/kg, and second ground for a crushing time of 30 min/kg depending on the dry powder weight for a total crushing time of 45 min/kg to form a minute powder. In experimental example 11 EX11, the dry powder was first ground for a crushing time of 10 min/kg, and second ground for a crushing time of 20 min/kg depending on the dry powder weight for a total crushing time of 30 min/kg to form a minute powder. In experimental example 12 EX12, the dry powder was first ground for a crushing time of 10 min/kg, and second ground for a crushing time of 20 min/kg depending on the dry powder weight for a total crushing time of 30 min/kg to form a minute powder. As an experimental result of experimental example 10 EX10, experimental example 11 EX11, and experimental example 12 EX12, the particle size distribution and the loss rate of the minute powder first ground and second ground from the dry powder are the same as in the table shown in
A mixture including 96 wt % to 98 wt % of an active material including a metal oxide, 0.1 wt % to 2 wt % of a conductive material including carbon black, and 1 wt % to 3 wt % of a binder including polytetrafluoroethylene (PTFE) was fiberized into a fiberized dry powder, and the dry powder was ground once for a crushing time of 30 min/kg according to the dry powder weight to form a minute powder. The minute powder was calendered using a multi-roll calendering device at a film calendering speed of 20 m/min to form a free-standing film having a 210 mm width. As an experimental result of comparative example 4 CO4, the particle size distribution of the minute powder ground once from the dry powder, and the loss rate of the minute powder are the same as in the table shown in
Comparative example 5 CO5 is the same as comparative example 4 CO4 except that the dry powder was ground once for a crushing time of 60 min/kg depending on the dry powder weight to form a minute powder. As an experimental result of comparative example 5 CO5, the particle size distribution and the loss rate of the minute powder ground once from the dry powder are the same as in the table shown in
According to the result of the second experiment of experimental example 9 EX9, experimental example 10 EX10, experimental example 11 EX11, experimental example 12 EX12, comparative example 4 CO4, and comparative example 5 CO5, compared to comparative example 4 CO4 and comparative example 5 CO5 where the dry powder was ground once into the minute powder, it was confirmed that the free-standing film thickness and the film loading level (film L/L) were uniform, and the film loss rate of the minute powder was minimized or reduced in each of experimental example 9 EX9, experimental example 10 EX10, experimental example 11 EX11, and experimental example 12 EX12 where the dry powder is first ground and second ground into the minute powder.
In some embodiments, according to the result of the second experiment of experimental example 9 EX9, experimental example 10 EX10, experimental example 11 EX11, experimental example 12 EX12, comparative example 4 CO4, and comparative example 5 CO5 described above, in order to achieve the task and effect of ensuring that the free-standing film thickness and the film loading level are uniform and the film loss rate of the minute powder are minimized or reduced, in the manufacturing method of the dry electrode according to an embodiment, for a numerically limited configuration in which the ratio of the particles with the minute powder between 45 μm and 1000 μm is 94 wt % to 99 wt % (e.g., an amount of particles having a particle size of 45 μm to 1000 μm being 94 wt % to 99 wt % based on 100 wt % of the minute powder), and the ratio of the particles with the minute powder less than 45 μm and greater than 1000 μm is 1 wt % to 6 wt % (e.g., a sum of an amount of particles having a particle size of less than 45 μm and an amount of particles having a particle size of greater than 1000 μm being 1 wt % to 6 wt % based on 100 wt % of the minute powder), it was confirmed that upper and lower limits have a threshold significance that may confirm that they are threshold values.
In some embodiments, according to the result of the second experiment of experimental example 9 EX9, experimental example 10 EX10, experimental example 11 EX11, experimental example 12 EX12, comparative example 4 CO4, and comparative example 5 CO5 described above, in order to achieve the task and effect of ensuring that the free-standing film thickness and the film loading level are uniform and the film loss rate of the minute powder are minimized or reduced, in the manufacturing method of the dry electrode according to an embodiment, for a numerically limited configuration in which the ratio of the particles with the minute powder between 45 μm and 1000 μm is 96 wt % to 98 wt % (e.g., an amount of particles having a particle size of 45 μm to 1000 μm being 96 wt % to 98 wt % based on 100 wt % of the minute powder), and the ratio of the particles with the minute powder less than 45 μm and greater than 1000 μm is 2 wt % to 4 wt % (e.g., a sum of an amount of particles having a particle size of less than 45 μm and an amount of particles having a particle size of greater than 1000 μm being 2 wt % to 4 wt % based on 100 wt % of the minute powder), it was confirmed that upper and lower limits have a threshold significance that may confirm that they are threshold values.
According to the second experimental result, in the manufacturing method of the dry electrode according to an embodiment, the fiberized dry powder is first ground and second ground into the minute powder, and the minute powder is calendered to the free-standing film, so that the length of the fiberized binder included in the dry powder is uniformly (or substantially uniformly) ground by the first crushing and the second crushing, and the minute powder ground from the dry powder has a set or predetermined particle size distribution, and accordingly the free-standing film having uniform (or substantially uniform) thickness and width may be manufactured by the calendering and concurrently (e.g., simultaneously) a loss rate of the minute powder and a loss rate of the film may be minimized or reduced during the free-standing film manufacturing.
Also, according to the second experimental result, in the manufacturing method of the dry electrode according to an embodiment, as the minute powder that is first ground and second ground from the fiberized dry powder includes a numerical limitation of the particle ratio of 45 μm to 1000 μm of 94 wt % to 99 wt % (e.g., an amount of particles having a particle size of 45 μm to 1000 μm being 94 wt % to 99 wt % based on 100 wt % of the minute powder) and the particle ratio of less than 45 μm and greater than 1000 μm of 1 wt % to 6 wt % (e.g., a sum of an amount of particles having a particle size of less than 45 μm and an amount of particles having a particle size of greater than 1000 μm being 1 wt % to 6 wt % based on 100 wt % of the minute powder), the minute powder ground from the dry powder has a set or predetermined particle size distribution, and accordingly the free-standing film having uniform (or substantially uniform) thickness and width may be manufactured by the calendering and concurrently (e.g., simultaneously) a loss rate of the minute powder and a loss rate of the film may be minimized or reduced during the free-standing film manufacturing.
Also, according to the result of the second experiment, in the manufacturing method of the dry electrode according to an embodiment, as the minute powder that is first ground and second ground from the fiberized dry powder includes a configuration of a threshold significance of a numerical limitation of the particle ratio of 45 μm to 1000 μm of 96 wt % to 98 wt % (e.g., an amount of particles having a particle size of 45 μm to 1000 μm being 96 wt % to 98 wt % based on 100 wt % of the minute powder) and the particle ratio of less than 45 μm and greater than 1000 μm of 2 wt % to 4 wt % (e.g., a sum of an amount of particles having a particle size of less than 45 μm and an amount of particles having a particle size of greater than 1000 μm being 2 wt % to 4 wt % based on 100 wt % of the minute powder), the minute powder ground from the dry powder has a set or predetermined particle size distribution, and accordingly the free-standing film having uniform (or substantially uniform) thickness and width may be manufactured by the calendering and concurrently (e.g., simultaneously) a loss rate of the minute powder and a loss rate of the film may be minimized or reduced during the free-standing film manufacturing.
While the subject matter of this disclosure has been described in connection with what is presently considered to be practical embodiments, it is to be understood that the disclosure is not limited to the disclosed embodiments. On the contrary, it is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, and equivalents thereof.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2023-0117867 | Sep 2023 | KR | national |
