Electrode sheet preparation device, electrode sheet preparation method and electrode sheet

Abstract

The present application belongs to the technical field of lithium-ion battery preparation. Disclosed are an electrode sheet preparation device, an electrode sheet preparation method and an electrode sheet. The electrode sheet preparation device comprises a coating assembly and a magnetization assembly, wherein in the conveying direction of a substrate, the coating assembly is located upstream of the magnetization assembly; the coating assembly is configured to coat a coating surface of the substrate with a slurry; and the magnetization assembly is configured to magnetize particles in the slurry so as to change the arrangement direction of the particles in the slurry. The present application can change the arrangement direction of particles in a slurry on a substrate on the basis of ensuring the production efficiency of an electrode sheet, thereby ensuring the diffusion effect of lithium ions and improving the performance of a lithium-ion battery.

Description

Pole piece preparation device, pole piece preparation method and pole piece

[0001] Cross-references of related documents

[0002] The present application claims priority to the Chinese patent application No. 202421758039.5, filed on July 22, 2024, entitled “Pole piece preparation device and pole piece”, the whole content of which is incorporated herein by reference. TECHNICAL FIELD

[0003] The present application relates to the technical field of preparation of lithium ion batteries, in particular to a pole piece preparation device, a pole piece preparation method and a pole piece. BACKGROUND

[0004] Coating is to uniformly, continuously or discontinuously coat the prepared paste-like thick slurry on the substrate such as the current collector, and at the same time, remove the solvent in the slurry laid on the current collector by drying and heating to make the solid substance well bonded to the substrate to form the positive pole piece material belt or the negative pole piece material belt of the lithium ion battery.

[0005] The lithium ion battery generally uses graphite as the negative active material, however, in the related art, the electrode structure can only be naturally baked into shape, and there is a lack of means to control the orientation of the particles. SUMMARY

[0006] In view of the above problems, the present application provides a pole piece preparation device, a pole piece preparation method and a pole piece, which can change the arrangement direction of the particles in the slurry on the substrate on the basis of ensuring the production efficiency of the pole piece, thereby ensuring the diffusion effect of lithium ions and improving the performance of the lithium ion battery.

[0007] In order to achieve the above-mentioned purpose, the present application provides the following technical solutions:

[0008] The first aspect of the embodiment of the present application provides a pole piece preparation device, comprising a coating assembly and a magnetization assembly; the coating assembly is located upstream of the magnetization assembly along the transmission direction of the substrate, the coating assembly is used for coating the slurry on the coated surface of the substrate, and the magnetization assembly is used for magnetizing the particles in the slurry to change the arrangement direction of the particles in the slurry.

[0009] In an implementable embodiment, further comprising a transmission assembly and a baking assembly; the transmission assembly is used for transmitting the substrate and driving the substrate to move along the transmission direction; the baking assembly is close to the discharge end of the transmission assembly, and the baking assembly is used for baking the substrate coated with the slurry.

[0010] In an implementation, the magnetizing assembly comprises a first magnetizing member and a second magnetizing member; the first magnetizing member is located outside the baking assembly and is arranged in proximity to the coated surface of the substrate between the baking assembly and the coating assembly; the second magnetizing member is located inside the baking assembly and is arranged in proximity to the coated surface of the substrate.

[0011] In an implementation, the number of magnetizing assemblies is plural; the plural magnetizing assemblies are arranged in proximity to opposite sides of the substrate along the thickness direction of the substrate; or, the plural magnetizing assemblies are arranged in proximity to one side of the lower surface of the substrate; or, the plural magnetizing assemblies are arranged in proximity to one side of the upper surface of the substrate.

[0012] In an implementation, the baking assembly comprises a first baking cavity and a second baking cavity in communication; the first baking cavity is located at one side of the first baking cavity in proximity to the discharge end of the conveying assembly; the second magnetizing member is located inside the first baking cavity and is arranged in proximity to the coated surface of the substrate.

[0013] In an implementation, the baking assembly is provided with plural blow assemblies arranged in proximity to the coated surface of the substrate; the blow assemblies are arranged in a staggered manner relative to the thickness direction of the substrate.

[0014] In an implementation, the blow assemblies comprise an upper blow member and a lower blow member; the upper blow member and the lower blow member are arranged at opposite sides of the baking assembly along the thickness direction of the substrate; the upper blow member and the lower blow member are respectively provided with the blow ports; the magnetizing assembly and the upper blow member are arranged in a staggered manner relative to the thickness direction of the substrate; and / or, the magnetizing assembly and the lower blow member are arranged in a staggered manner relative to the thickness direction of the substrate; and / or, the upper blow member and the lower blow member are arranged in a staggered manner relative to the thickness direction of the substrate.

[0015] In an implementation, the magnetizing assembly is further provided with a lifting member connected thereto; the lifting member is configured to drive the lifting of the magnetizing assembly; the pole piece preparation device is further provided with a translation member connected to the magnetizing assembly; the translation member is configured to drive the translation of the magnetizing assembly.

[0016] In an implementation, an angle adjusting member is further included for adjusting the angle between the magnetization assembly and the substrate plane. In an implementation, a power supply member is further included and electrically connected to the lifting member and the translation member respectively, and is configured to supply power to the lifting member and the translation member; and the pole piece preparation device further includes a control member electrically connected to the lifting member and the translation member respectively, and configured to control the lifting of the lifting member and the translation of the translation member.

[0017] In an implementation, a magnetic induction member is further included and disposed on the magnetization assembly, and is electrically connected to the control member, and is configured to sense the magnetic field intensity value of the magnetization assembly and send the magnetic field intensity value to the control member; and / or, the pole piece preparation device further includes a magnetic shielding protection member disposed on the magnetization assembly.

[0018] In an implementation, the distance between the magnetization assembly and the substrate surface along the thickness direction of the substrate is not greater than 2 mm; and / or, the length of the baking assembly is 2 times the length of the substrate moving at a preset speed within a preset time.

[0019] In an implementation, the first magnetization member is a permanent magnet or an electromagnet, the magnetic field intensity of the first magnetization member ranges from 0.4 T to 2 T, the magnetic field width of the first magnetization member ranges from 150 mm to 1500 mm, and the magnetic field length of the first magnetization member ranges from M / 5n; and / or, the second magnetization member is a permanent magnet, the magnetic field intensity of the second magnetization member ranges from 0.4 T to 2 T, the magnetic field width of the second magnetization member ranges from 150 mm to 1500 mm, and the magnetic field length of the second magnetization member ranges from M / 5n; wherein, M is the moving speed of the substrate, in units of m / min, and n is the number of magnetization assemblies.

[0020] The second aspect of the embodiments of the present application provides a pole piece preparation method, which adopts a pole piece preparation device; the pole piece preparation method includes: inputting a substrate onto a transmission assembly and driving the substrate to move; coating a slurry on the coated surface of the substrate by a coating assembly; performing primary magnetization on the particles in the slurry by a magnetization assembly; performing secondary magnetization on the particles in the primary magnetized slurry by the magnetization assembly, and performing baking on the magnetized substrate by a baking assembly.

[0021] In an implementation, the baking of the magnetized substrate by the baking assembly includes: performing primary baking on the substrate after the primary magnetization and before the secondary magnetization by the baking assembly; and performing secondary baking on the substrate after the secondary magnetization and the primary baking by the baking assembly.

[0022] A third aspect of the embodiments of the present application provides a pole piece, which is prepared by a pole piece preparation method or is prepared by a pole piece preparation device.

[0023] The embodiments of the present application provide a pole piece preparation device, a pole piece preparation method and a pole piece. By including a coating assembly, the coating assembly can supply slurry and achieve the effect of coating on the coating surface of the substrate. By including a magnetization assembly, the magnetization assembly is located downstream of the coating assembly, which helps to magnetize the particles in the slurry on the substrate after the slurry is coated, thereby helping to prolong the magnetization path of the particles in the slurry, increase the magnetization area of the particles in the slurry, and further help to change the arrangement direction of the particles in the slurry on the substrate to the greatest extent, ensure that the plane of the particles in the slurry is perpendicular to the plane of the substrate, and significantly improve the consistency of the arrangement of the particle plane in the vertical direction of the substrate plane, thereby ensuring the diffusion effect of lithium ions, reducing the resistivity and battery internal resistance, improving the charging capacity, slowing down the deterioration of the battery, and thereby maximizing the low-temperature, rate and cycle performance of the lithium ion battery. BRIEF DESCRIPTION OF DRAWINGS

[0024] FIG. 1 is a structural schematic diagram of a pole piece preparation device provided by the embodiments of the present application;

[0025] FIG. 2 is a top view of the pole piece preparation device provided by the embodiments of the present application;

[0026] FIG. 3 is a structural schematic diagram of the distance between the magnetization assembly and the surface of the substrate provided by the embodiments of the present application;

[0027] FIG. 4 is a process flow diagram of a pole piece preparation method provided by the embodiments of the present application.

[0028] Reference signs: 100-pole piece preparation device; 110-transport assembly; 111-unwinding piece; 112-winding piece; 113-feeding end; 114-discharging end; 120-coating assembly; 130-magnetization assembly; 131-first magnetization piece; 132-second magnetization piece; 140-baking assembly; 141-first baking cavity; 142-second baking cavity; 150-blowing assembly; 151-upper blowing piece; 152-lower blowing piece; 160-power supply piece; 170-control piece; 200-substrate; 210-coating surface. DETAILED DESCRIPTION

[0029] Lithium ion batteries generally use graphite as a negative active material, which has a layered structure. During battery charging, lithium ions are inserted into the interlayer space of the graphite layer from the edge of the layered graphite, thereby obtaining a Li-graphite intercalation compound.

[0030] During the preparation of the negative electrode sheet, the plane of the graphite particles is generally parallel to the plane of the current collector. However, during the charging and discharging process of the lithium ion battery, lithium ions tend to diffuse in a direction perpendicular to the plane of the current collector. For example, if lithium ions are inserted into the interlayer space of the graphite layer from the edge of the layered graphite in a direction parallel to the plane of the current collector during charging, the transport path of the lithium ions will be lengthened, and the interlayer spacing of the graphite layer will be smaller, resulting in greater diffusion resistance of the lithium ions. Therefore, in order to reduce the resistance of the lithium ions during diffusion and improve the diffusion effect of the lithium ions, the arrangement direction of the graphite particles is generally changed so that the arrangement direction of the graphite particles is perpendicular to the plane of the current collector.

[0031] In the related art, the arrangement direction of the graphite particles on the plane of the current collector is generally changed by using a magnetic field. Specifically, the negative electrode slurry is coated on the substrate, and then a certain applied magnetic field is applied to the substrate to change the arrangement direction of the graphite particles, and then the negative electrode sheet is obtained by drying and compacting. However, in the related art, the magnetization effect of the graphite particles is low, and after the magnetic field is removed, a part of the graphite particles will still be turned in the slurry, the change effect of the arrangement direction of the graphite particles is poor, and the diffusion resistance of the lithium ions is still large.

[0032] To solve the above technical problems, the embodiment of the present application provides an electrode sheet preparation device, an electrode sheet preparation method and an electrode sheet. By including a transmission assembly, it is helpful to realize the movement of the substrate along the transmission direction, and then to ensure that the coating surface of the substrate can be normally coated and baked; by including a coating assembly, it can supply the slurry and realize the coating on the coating surface of the substrate; by including a baking assembly, it is helpful to realize the baking of the substrate coated with the slurry until it becomes a solid, and finally the electrode sheet is obtained by compacting; by including a magnetization assembly, the magnetization assembly is located downstream of the coating assembly, so it is helpful to magnetize the particles in the slurry on the substrate after the slurry is coated, thereby being beneficial to prolong the magnetization path of the particles in the slurry, increase the magnetization area of the particles in the slurry, and then being beneficial to change the arrangement direction of the particles in the slurry on the substrate to the greatest extent, ensure that the plane of the particles in the slurry is perpendicular to the plane of the substrate, and significantly improve the consistency of the arrangement of the plane of the particles in the perpendicular direction of the plane of the substrate, thereby being able to ensure the diffusion effect of the lithium ions, reduce the resistivity and the internal resistance of the battery, improve the charging capacity, slow down the deterioration of the battery, and thereby maximize the low-temperature, rate and cycle performance of the lithium ion battery.

[0033] For the purposes of the present application, the technical solutions and advantages, the technical solutions in the embodiments of the present application will be described in more detail below with reference to the drawings in the embodiments of the present application. In the drawings, the same or similar notations represent the same or similar parts or parts having the same or similar functions throughout. The described embodiments are part of the embodiments of the present application, not all of the embodiments. The embodiments described below by reference to the drawings are exemplary and are intended to explain the present application, and cannot be understood as limiting the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0034] Referring to FIG. 1 and FIG. 2, the present application provides a pole piece preparation device 100, which can include a transmission assembly 110, a coating assembly 120, a magnetization assembly 130 and a baking assembly 140.

[0035] It should be noted that the pole piece preparation device 100 provided in the present embodiment can be used to prepare a positive pole piece, or the pole piece preparation device 100 provided in the present embodiment can be used to prepare a negative pole piece. In the present embodiment, the preparation of a negative pole piece is mainly taken as an example for description.

[0036] In the present application, the transmission assembly 110 is used to transmit the base material 200 and drive the base material 200 to move along the transmission direction. In the working process, referring to FIG. 1, the transmission assembly 110 can include an unwinding part 111 and a winding part 112, the unwinding part 111 is a device for unwinding and flattening the base material 200, and the winding part 112 is a device for winding the base material 200.

[0037] For example, the unwinding part 111 can be an unwinding roller, and the winding part 112 can be a winding roller. The unwinding part 111 can drive the rotation of the roller by a motor, so that the winding core on the unwinding part 111 rotates continuously, so that the base material 200 always maintains uniform tension. The winding part 112 can also be driven by a motor to rotate.

[0038] It should be noted that the transmission direction of the base material 200 is not limited in the present embodiment, and the transmission of the base material 200 can be carried out according to actual needs. For example, the transmission direction of the base material 200 can be shown in the direction of arrow A in FIG. 1 and FIG. 2.

[0039] It should be noted that the type of the substrate 200 is not limited in the embodiment. For example, the substrate 200 can be a copper foil current collector, or the substrate 200 can be an aluminum foil current collector, which is not limited in the embodiment. It should be noted that the current collector is also called an electrolyte, which can provide an ion conductor in an electrochemical reaction, and the main function is to allow ion transfer between positive and negative charges to maintain the flow of current.

[0040] In the embodiment, the coating assembly 120 is arranged close to the inlet end 113 of the conveying assembly 110 along the conveying direction of the substrate 200, and the coating assembly 120 is used to coat the slurry on the coated surface 210 of the substrate 200.

[0041] For example, the coating assembly 120 can include a slurry tank, which can be used to store the slurry to be coated on the coated surface 210 of the substrate 200. For example, a coating pump nozzle can be installed on the slurry tank, so that the coated surface 210 of the substrate 200 is coated through the coating pump nozzle. This is not limited in the embodiment.

[0042] It should be noted that the substrate 200 includes an upper surface and a lower surface, so the coated surface 210 of the substrate 200 can refer to the upper surface of the substrate 200, or the coated surface 210 of the substrate 200 can refer to the lower surface of the substrate 200. In the actual coating process, the upper surface and the lower surface of the substrate 200 generally need to be coated, for example, the negative electrode slurry can be extrusion coated or sprayed on the upper and lower surfaces of the substrate 200. In addition, the thickness of the coating is not limited, and a reasonable coating thickness can be determined according to actual needs, which is not limited in the embodiment.

[0043] It should be noted that the coating assembly 120 is arranged close to the inlet end 113 of the conveying assembly 110. In this way, it is helpful to ensure that the substrate 200 can be coated from the beginning of the transmission, to ensure that the coated surface 210 of the substrate 200 is accumulated, thereby maximizing the coating effect of the substrate 200. The specific distance between the coating assembly 120 and the inlet end 113 is not limited, and can be set according to actual needs.

[0044] In the embodiment, the baking assembly 140 is arranged close to the outlet end 114 of the conveying assembly 110, and the baking assembly 140 is used to bake the substrate 200 coated with the slurry.

[0045] For example, the baking assembly 140 can be a baking oven, and the shape, size, etc. of the baking oven are not limited, and can be set according to actual needs.

[0046] It can be understood that the baking assembly 140 has an inlet and an outlet, the inlet is close to the coating assembly 120, and the outlet is close to the discharge end 114 of the conveying assembly 110. In actual work, the substrate 200 coated with the slurry enters the baking assembly 140 through the inlet, is baked for a period of time until it becomes a solid state, is conveyed through the outlet and is wound by the winding member 112, and finally is compacted to obtain the negative plate.

[0047] It should be noted that the baking time of the substrate 200 coated with the slurry is not limited, and can be set according to the coating thickness or the coating surface 210 of the slurry on the substrate 200. The present embodiment does not limit this.

[0048] It should be noted that the baking assembly 140 is arranged close to the discharge end 114 of the conveying assembly 110. This is because, if the baking assembly 140 is arranged too close to the inlet end 113, the substrate 200 coated with the slurry is baked from the beginning of the transmission, which leads to a high adhesion between the particles in the slurry and the coating surface 210 from the beginning of the transmission, and further leads to that the magnetizing assembly 130 is not easy to change the arrangement direction of the particles in the slurry. Therefore, in the present embodiment, the baking assembly 140 is arranged close to the discharge end 114 of the conveying assembly 110, which helps to ensure the magnetization of the particles in the slurry, so as to change the arrangement direction of the particles in the slurry on the substrate 200.

[0049] In the present embodiment, the magnetizing assembly 130 is located downstream of the coating assembly 120 along the transmission direction of the substrate 200, and the magnetizing assembly 130 is used to magnetize the particles in the slurry to change the arrangement direction of the particles in the slurry.

[0050] It should be noted that the magnetizing assembly 130 is located downstream of the coating assembly 120, which can also be understood as that the magnetizing assembly 130 is located after the coating assembly 120 along the transmission direction of the substrate 200. The specific position of the magnetizing assembly 130 is not limited.

[0051] For example, the magnetizing assembly 130 in the present embodiment can be a magnet, for example, the magnetizing assembly 130 can be a permanent magnet, or the magnetizing assembly 130 can be an electromagnet. The present embodiment does not limit this.

[0052] It should be noted that the magnetization principle of the magnetizing assembly 130 in the present embodiment is that the magnetizing assembly 130 has a magnetic circuit, the magnetic circuit is perpendicular to the surface of the substrate 200, and under the magnetic field force of the magnetizing assembly 130, the arrangement direction of the particles in the slurry is changed from parallel to the surface of the substrate 200 to perpendicular to the surface of the substrate 200.

[0053] Therefore, the pole piece preparation device 100 provided by the application can magnetize the particles in the slurry on the substrate 200 after the slurry is coated, thereby prolonging the magnetization path of the particles in the slurry, increasing the magnetization area of the particles in the slurry, and changing the arrangement direction of the particles in the slurry on the substrate 200 to the greatest extent, ensuring that the plane of the particles is perpendicular to the plane of the substrate 200, and significantly improving the consistency of the arrangement of the plane of the particles in the vertical direction of the plane of the substrate 200, thereby ensuring the diffusion effect of lithium ions and maximizing the low-temperature, rate, and cycle performance of the lithium ion battery made of the slurry while ensuring the production efficiency of the pole piece.

[0054] In an implementable embodiment, the magnetizing assembly 130 can include a first magnetizing piece 131 and a second magnetizing piece 132. The first magnetizing piece 131 can be located outside the baking assembly 140 and between the baking assembly 140 and the coating assembly 120 and arranged in proximity to the coated surface 210 of the substrate 200, and the second magnetizing piece 132 can be located inside the baking assembly 140 and arranged in proximity to the coated surface 210 of the substrate 200.

[0055] In the embodiment of the application, the first magnetizing piece 131 can be located outside the baking assembly 140 and between the baking assembly 140 and the coating assembly 120. In this way, the adhesion between the ions in the slurry and the coated surface 210 is low during the coating of the substrate 200 and before baking. When the first magnetizing piece 131 magnetizes the particles in the slurry, the resistance of the particles in the slurry during rotation is low, and therefore, when the viscosity of the slurry is low, the arrangement direction of the particles is more likely to be inverted to the direction parallel to the plane of the substrate 200.

[0056] In the embodiment of the application, the second magnetizing piece 132 can be located inside the baking assembly 140. In this way, the magnetization and baking can be performed simultaneously, so that the magnetization is completed at the same time as the baking, which helps to save the preparation time of the process and also helps to save the preparation process of the process and improve the preparation efficiency.

[0057] In the embodiment of the application, the first magnetizing piece 131 and the second magnetizing piece 132 are arranged in proximity to the coated surface 210 of the substrate 200, which helps to avoid the problem that the first magnetizing piece 131 and the second magnetizing piece 132 directly contact the substrate 200 and affect the coating of the substrate 200, thereby maximizing the coating effect of the substrate 200.

[0058] It should be noted that the number and arrangement of the first magnetizing piece 131 are not limited, and can be set as required. Similarly, the number and arrangement of the second magnetizing piece 132 are not limited, and can be set as required.

[0059] In an implementation, the number of magnetizing assemblies 130 can be multiple. For example, the number of magnetizing assemblies 130 can be two, three, eight or more. The number of magnetizing assemblies 130 is not limited in the embodiment.

[0060] It should be noted that the positions of the multiple magnetizing assemblies 130 are not limited in the embodiment. For example, the positions of the multiple magnetizing assemblies 130 can be set in the following manner. It should be noted that the positions of the multiple magnetizing assemblies 130 include but are not limited to the following manner.

[0061] In some embodiments, the multiple magnetizing assemblies 130 can be respectively arranged near opposite sides of the substrate 200 along the thickness direction of the substrate 200. In this way, the generated magnetic field can form a magnetic field with consistent and uniform direction in the entire action area, and thus the particles can be arranged in a consistent plane perpendicular to the substrate 200.

[0062] In some embodiments, the multiple magnetizing assemblies 130 can be arranged near the lower surface of the substrate 200. In this way, the magnetizing assembly 130 magnetizes the particles in the slurry from the lower surface of the substrate 200, which is beneficial to avoid affecting the normal coating of the substrate 200, and thus ensures the continuous coating of the substrate 200 and the coating effect of the substrate 200.

[0063] In some embodiments, the multiple magnetizing assemblies 130 can also be arranged near the upper surface of the substrate 200. The embodiment is not limited in this regard.

[0064] In the embodiment, referring to FIG. 1, the multiple magnetizing assemblies 130 are mainly described by way of example arranged near the lower surface of the substrate 200.

[0065] In an implementation, referring to FIGS. 1 and 2, the baking assembly 140 can include a first baking cavity 141 and a second baking cavity 142 connected in communication, and the second baking cavity 142 is located at the side of the first baking cavity 141 near the discharge end 114 of the conveying assembly 110. The second magnetizing member 132 is arranged in the first baking cavity 141 and spaced apart from the coating surface 210 of the substrate 200.

[0066] In the embodiment, the second magnetizing member 132 is arranged in the first baking cavity 141 because the first baking cavity 141 is in the initial baking stage, at which the baking temperature of the substrate 200 in the first baking cavity 141 is relatively low, the adhesion between the particles in the slurry and the coating surface 210 is relatively low, and the particles in the slurry are less resistant to turning under the magnetic field of the second magnetizing member 132. Therefore, the magnetizing assembly 130 can easily change the arrangement direction of the particles in the slurry, thereby helping to improve the arrangement consistency of the particles in the plane.

[0067] In the embodiment, the second baking cavity 142 is not provided with the second magnetizing member 132, because the baking temperature in the second baking cavity 142 is relatively high, the adhesion between the particles in the slurry and the coating surface 210 is relatively high, and the magnetizing assembly 130 is not easy to change the arrangement direction of the particles in the slurry. Therefore, the second baking cavity 142 only realizes baking of the slurry on the substrate 200, so that the particles in the slurry are arranged in the same direction after the magnetization and baking.

[0068] In an implementable embodiment, referring to FIGS. 1 and 2, the baking assembly 140 can be provided with a plurality of blowing assemblies 150 at intervals, the blowing assembly 150 has a blowing port, the blowing port faces the coating surface 210 of the substrate 200, and the blowing assembly 150 and the magnetizing assembly 130 are arranged in a staggered manner with respect to the thickness direction of the substrate 200.

[0069] It should be noted that the blowing assembly 150 in the embodiment mainly blows hot air. In this way, hot air is blown while the baking assembly 140 is baking, which helps to improve the drying speed of the substrate 200 coated with the slurry.

[0070] In the embodiment, the number and arrangement of the blowing assembly 150 are not limited, and can be set according to actual needs. In addition, the position of the blowing assembly 150 is not limited, for example, the blowing assembly 150 can be arranged in the first baking cavity 141, or the blowing assembly 150 can be arranged in the second baking cavity 142. The embodiment does not limit this.

[0071] It should be noted that the blowing assembly 150 and the magnetizing assembly 130 are arranged in a staggered manner with respect to the thickness direction of the substrate 200. In this way, it is helpful to avoid the interference between the blowing assembly 150 and the magnetizing assembly 130, and to ensure that the blowing assembly 150 normally blows air to the coating surface 210 of the substrate 200 and that the magnetizing assembly 130 normally magnetizes the particles in the slurry.

[0072] It should be noted that the staggered arrangement means that the blowing assembly 150 and the magnetizing assembly 130 do not overlap each other in the orthographic projection on the same horizontal plane of the substrate 200.

[0073] In an implementable embodiment, referring to FIGS. 1 and 2, the blowing assembly 150 can include an upper blowing member 151 and a lower blowing member 152, the upper blowing member 151 and the lower blowing member 152 are arranged on opposite sides of the baking assembly 140 along the thickness direction of the substrate 200, and the upper blowing member 151 and the lower blowing member 152 each have a blowing port.

[0074] Exemplarily, the upper blowing member 151 can be an upper blowing nozzle, and the lower blowing member 152 can be a lower blowing nozzle, which are not limited in the embodiment.

[0075] In some embodiments, the magnetizing assembly 130 and the upper blowing member 151 can be arranged in a staggered manner relative to the thickness direction of the base material 200, which can help to avoid mutual interference of the magnetizing assembly 130 and the upper blowing member 151. In some embodiments, the magnetizing assembly 130 and the lower blowing member 152 can be arranged in a staggered manner relative to the thickness direction of the base material 200, which can help to avoid mutual interference of the magnetizing assembly 130 and the lower blowing member 152. In some embodiments, the upper blowing member 151 and the lower blowing member 152 can be arranged in a staggered manner relative to the thickness direction of the base material 200, which can help to avoid mutual interference of the upper blowing member 151 and the lower blowing member 152, thereby maximizing the blowing amount and ensuring the blowing effect.

[0076] It should be noted that the arrangement of the upper blowing member 151, the lower blowing member 152, and the magnetizing assembly 130 in the embodiment includes but is not limited to the above-mentioned multiple arrangements.

[0077] In an implementable embodiment, a lifting member can be further included, which is connected to the magnetizing assembly 130 and is configured to drive the lifting of the magnetizing assembly 130.

[0078] The type of the lifting member is not limited in the embodiment. Exemplarily, the lifting member can be an electric screw rod, which is configured to drive the lifting or lowering of the magnetizing assembly 130, thereby helping to adjust the position of the magnetizing device according to the actual position of the base material 200, and the automation degree is high.

[0079] Exemplarily, the lifting range of the lifting member can be between 0-20 mm, and the lifting precision of the lifting member can be 0.05°, which is high. The embodiment is not limited in this regard.

[0080] In the embodiment, the pole piece preparation device 100 can further include a translation member, which is connected to the magnetizing assembly 130 and is configured to drive the horizontal movement of the magnetizing assembly 130.

[0081] The type of the translation member is not limited in the embodiment. Exemplarily, the translation member can be a sliding block, and the magnetizing assembly 130 can be provided with a sliding groove, and the sliding block is configured to slide in the sliding groove to realize the translation of the magnetizing assembly 130; or the translation member can be a sliding groove, and the magnetizing assembly 130 can be provided with a pulley. The embodiment is not limited in this regard.

[0082] In the embodiment, the pole piece preparation device 100 can further include an angle adjusting member, which is configured to adjust the angle between the magnetizing assembly 130 and the plane of the base material 200, so as to ensure the magnetization accuracy in the magnetization process. For example, the angle adjusting range of the angle adjusting member can be between -10° and +10°, and the adjustment accuracy of the angle adjusting member is not greater than 0.5°, which is relatively high. The embodiment is not limited in this regard.

[0083] In an implementation, as shown in FIGS. 1 and 2, the pole piece preparation device 100 can further include a power supply 160, which is electrically connected to the lifting member and the translation member, respectively, and is configured to supply power to the lifting member and the translation member.

[0084] The type of the power supply 160 is not limited in the embodiment. For example, the power supply 160 can be an electric box, or the power supply 160 can be a direct current power supply or a stabilized power supply. The embodiment is not limited in this regard. In addition, the electrical connection between the power supply 160 and the lifting member and the translation member is not limited, for example, the electrical connection can be achieved by wired or wireless connection.

[0085] In the embodiment, as shown in FIGS. 1 and 2, the pole piece preparation device 100 can further include a control member 170, which is electrically connected to the lifting member and the translation member, respectively, and is configured to control the lifting of the lifting member and the horizontal movement of the translation member.

[0086] The type of the control member 170 is not limited in the embodiment. For example, the control member 170 can be a controller.

[0087] In an implementation, the pole piece preparation device 100 can further include a magnetic induction member, which is arranged on the magnetizing assembly 130, and is electrically connected to the control member 170, and is configured to sense the magnetic field intensity value of the magnetizing assembly 130 and send the magnetic field intensity value to the control member 170.

[0088] For example, the magnetic induction member can be a magnetic induction probe, which is a sensor for detecting the magnetic field intensity. The magnetic induction probe mainly utilizes the principle of electromagnetic induction to determine the magnetic field intensity and direction by detecting the change of the magnetic field. In this way, the control member 170 can help to determine the strength of the magnetic field according to the magnetic field intensity value, so as to place more magnetizing assemblies 130 in the area with weaker magnetic field.

[0089] In the embodiment, the pole piece preparation device 100 can further include a magnetic shielding protection member, which is arranged above the magnetizing assembly 130 to form a protection state of the magnetizing assembly 130.

[0090] It should be noted that the magnetic shielding protection piece can be a magnetic shielding protection plate. The magnetic shielding protection plate is mainly applied to the state that the magnetization assembly 130 is in an unused or used state. Placing the magnetic shielding protection plate above the magnetization assembly 130 helps to prevent the magnetic position from falling onto the magnetization assembly 130, thereby ensuring the structural integrity of the magnetization assembly 130, avoiding the risk of damage to the magnetization assembly 130, ensuring the normal work of the magnetization assembly 130, and helping to prolong the service life of the magnetization assembly 130.

[0091] In an implementable embodiment, the distance between the magnetization assembly 130 and the surface of the substrate 200 in the thickness direction of the substrate 200 can be not greater than 2 mm.

[0092] In the embodiment of the present application, the distance d between the magnetization assembly 130 and the lower surface of the substrate 200 is not greater than 2 mm. For example, referring to FIG. 3, the distance d between the magnetization assembly 130 and the surface of the substrate 200 can be set to 0 mm, 0.5 mm, 1 mm, 1.5 mm, 2 mm or any value not greater than 2 mm according to actual needs.

[0093] If the distance between the magnetization assembly 130 and the surface of the substrate 200 is greater than 2 mm, the magnetization assembly 130 is prone to weaken the magnetization force on the substrate 200 coated with slurry, and it is not easy to change the arrangement direction of the particles in the slurry on the substrate 200. Therefore, in the embodiment of the present application, the distance between the magnetization assembly 130 and the surface of the substrate 200 is not greater than 2 mm, which is beneficial to ensure the magnetization force of the magnetization assembly 130 on the slurry coated with particles, and further change the arrangement direction of the particles in the slurry on the substrate 200.

[0094] In the embodiment of the present application, the length of the baking assembly 140 can be 2 times the length of the substrate 200 moving at a preset speed within a preset time. For example, taking the maximum moving speed of the substrate 200 as 90 m / min, the length of the baking assembly 140 is 180 m. In this way, the complete baking of the substrate 200 can be guaranteed to the greatest extent, which is beneficial to avoid the problem that the baking cannot be realized in time when the moving speed of the substrate 200 is too fast.

[0095] In an implementable embodiment, the first magnetization piece 131 can be a permanent magnet or an electromagnet, and the second magnetization piece 132 can be a permanent magnet.

[0096] It should be noted that the permanent magnet refers to a magnet that can continuously maintain a certain magnetic field, which is made of hard magnetic material, such as ferrite. The electromagnet is a device that generates a magnetic field around the coil through electric current, such as an electromagnetic coil.

[0097] It should be noted that the first magnetizing element 131 is a permanent magnet or an electromagnet because the external environment of the baking assembly 140 is not a high-temperature environment, so it will not affect the electromagnet. The second magnetizing element 132 is a permanent magnet because the internal environment of the baking assembly 140 is a high-temperature environment, which can easily cause the electromagnet's own temperature to be too high, resulting in high resistance of the electromagnet, high energy consumption of the electromagnet, and the risk of the electromagnet itself melting or being damaged.

[0098] In this embodiment, the magnetic field strength of the first magnetizing element 131 can range from 0.4T to 2T, the magnetic field width of the first magnetizing element 131 can range from 150mm to 1500mm, and the magnetic field length of the first magnetizing element 131 can be M / 5n. The specific values ​​of the magnetic field strength and magnetic field width of the first magnetizing element 131 are not further limited; for example, the magnetic field width of the first magnetizing element 131 can be consistent with the width of the substrate 200.

[0099] In this embodiment, the magnetic field strength of the second magnetizing element 132 can range from 0.4T to 2T, the magnetic field width of the second magnetizing element 132 can range from 150mm to 1500mm, and the magnetic field length of the second magnetizing element 132 can be M / 5n. The specific values ​​of the magnetic field strength and magnetic field width of the second magnetizing element 132 are not further limited; for example, the magnetic field width of the second magnetizing element 132 can be consistent with the width of the substrate 200.

[0100] Where M is the moving speed of the substrate 200 in m / min, and n is the number of magnetizing components 130. It should be noted that, under normal circumstances, the total time of the magnetic field action in this application is controlled within 12s. Therefore, the derivation formula of M / 5n is: M / 60*12=M / 5, where 60 is 1min in seconds and 12 is in seconds.

[0101] For example, the total number of magnetization components 130 is 6, and the magnetic field length of magnetization component 130 is M / 5*6=M / 30.

[0102] In one feasible implementation, the magnetic circuit configuration of the magnetization component 130 is not limited in this embodiment. For example, the magnetic circuit configuration of the magnetization component 130 may be a single pole arrangement with the poles facing upwards; or, the magnetic circuit configuration of the magnetization component 130 may be an alternating N / S arrangement with the poles facing upwards; or, the magnetic circuit configuration of the magnetization component 130 may be a like pole arrangement with the poles facing each other. This embodiment does not limit this.

[0103] Referring to Figure 4, this application also provides an electrode preparation method for an electrode preparation apparatus. The electrode preparation method may include:

[0104] S100: Input the substrate onto the transmission component and move the substrate.

[0105] In this embodiment, the moving speed of the substrate is not limited.

[0106] S200: The coating component applies a slurry to the coating surface of the substrate.

[0107] In this embodiment, taking the preparation of a negative electrode sheet as an example, the negative electrode slurry can be a graphite slurry, which can be sprayed onto the coating surface 210 of the substrate 200 by extrusion coating or spraying.

[0108] In this embodiment, the coating surface 210 may include the upper surface and the lower surface of the substrate 200, and both the upper surface and the lower surface are coated. The coating order of the upper surface and the lower surface is not limited.

[0109] S300: The magnetization component performs initial magnetization on the particles in the slurry.

[0110] In this embodiment, the initial magnetization refers to magnetizing the particles in the slurry located outside the baking assembly 140 and between the baking assembly 140 and the coating assembly 120.

[0111] S400: The magnetization component performs secondary magnetization on the particles in the initially magnetized slurry, and the baking component bakes the magnetized substrate.

[0112] In this embodiment, secondary magnetization refers to magnetizing the particles coated with slurry located in the first baking cavity 141.

[0113] In this embodiment, the baking assembly 140 bakes the magnetized substrate 200, which may include: the baking assembly 140 baking the initially magnetized substrate 200, or the baking assembly 140 baking the secondarily magnetized substrate 200. This embodiment does not limit this.

[0114] In one feasible implementation, the process of baking the magnetized substrate 200 by the baking assembly 140 may further include: the baking assembly 140 performing a first baking on the substrate 200 after initial magnetization and during the second magnetization process; and the baking assembly 140 performing a second baking on the substrate 200 after secondary magnetization and the first baking.

[0115] In this embodiment, the initial baking of the substrate 200 after initial magnetization and during the secondary magnetization process by the baking component 140 refers to the baking of the substrate 200 by the first baking cavity 141.

[0116] In this embodiment, the secondary baking of the substrate 200 after secondary magnetization and initial baking by the baking component 140 refers to the baking of the substrate 200 by the second baking cavity 142.

[0117] This application provides an electrode sheet, which is prepared using an electrode sheet preparation method; or, the electrode sheet is prepared using an electrode sheet preparation apparatus 100. This embodiment does not limit the method.

[0118] For example, the electrode can be a positive electrode or a negative electrode. In this embodiment, the preparation of a negative electrode is mainly used as an example for explanation.

[0119] Therefore, embodiments of this application provide an electrode preparation apparatus, an electrode preparation method, and an electrode. By including a transport component, it facilitates the movement of the substrate along the transport direction, thereby ensuring proper coating and baking on the substrate's coating surface. By including a coating component, it supplies the slurry and coats the substrate's coating surface. By including a baking component, it facilitates baking the slurry-coated substrate until it becomes solid, and finally, compaction yields the electrode. By including a magnetization component, located downstream of the coating component, it facilitates the immediate application of the slurry to the substrate. Magnetizing the particles in the slurry helps to extend the magnetization path and increase the magnetization area of ​​the particles in the slurry. This, in turn, helps to change the arrangement direction of the particles in the slurry on the substrate to the greatest extent, ensuring that the plane of the particles in the slurry is perpendicular to the plane of the substrate. It also helps to significantly improve the consistency of the particle plane in the direction perpendicular to the plane of the substrate. This ensures the diffusion effect of lithium ions while maintaining the production efficiency of the electrode, reduces resistivity and battery internal resistance, improves charging capacity, and slows down battery deterioration. In this way, it maximizes the low-temperature, rate, and cycle performance of lithium-ion batteries.

[0120] It should be noted that, in the description of the embodiments of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an indirect connection through an intermediate medium, or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0121] In the description of the embodiments of this application, the term "and / or" merely indicates a relationship describing the associated objects, meaning that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the term "at least one" indicates any combination of at least two of a plurality of options, for example, including at least one of A, B, and C, which can represent any one or more elements selected from a set including communication between A, B, and C.

[0122] In the description of the embodiments of this application, the terms "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. In addition, the term "multiple" means two or more, unless otherwise precisely specified.

[0123] In the description of the embodiments of this application, the terms "first," "second," "third," "fourth," etc. (if present) are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0124] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. An electrode tab preparation device, characterized by, The coating assembly (120) and the magnetization assembly (130) are included. The coating assembly (120) is located upstream of the magnetization assembly (130) along the conveying direction of the substrate (200), the coating assembly (120) is used for coating the slurry on the coating surface (210) of the substrate (200), and the magnetization assembly (130) is used for magnetizing the particles in the slurry to change the arrangement direction of the particles in the slurry.

2. The pole piece preparation apparatus of claim 1, wherein The conveying assembly (110) and the baking assembly (140) are further included. The conveying assembly (110) is used for conveying and moving the substrate (200) along the conveying direction, and the baking assembly (140) is located close to the discharge end (114) of the conveying assembly (110), and the baking assembly (140) is used for baking the substrate (200) coated with the slurry.

3. The pole piece preparation apparatus of claim 2, wherein The magnetization assembly (130) includes a first magnetization component (131) and a second magnetization component (132). The first magnetization component (131) is located outside the baking assembly (140) and is located between the baking assembly (140) and the coating assembly (120) and is spaced apart close to the coating surface (210) of the substrate (200). The second magnetization component (132) is located inside the baking assembly (140) and is spaced apart close to the coating surface (210) of the substrate (200).

4. The pole piece preparation apparatus of claim 3, wherein The number of the magnetization assembly (130) is multiple. Along the thickness direction of the substrate (200), multiple magnetization assemblies (130) are respectively arranged close to opposite sides of the substrate (200). Or, multiple magnetization assemblies (130) are arranged close to one side of the lower surface of the substrate (200). Or, multiple magnetization assemblies (130) are arranged close to one side of the upper surface of the substrate (200).

5. The pole piece preparation apparatus of claim 4, wherein The baking assembly (140) includes a first baking cavity (141) and a second baking cavity (142) in communication, and the second baking cavity (142) is located on one side of the first baking cavity (141) close to the discharge end (114) of the conveying assembly (110). The second magnetization component (132) is located in the first baking cavity (141) and is spaced apart close to the coating surface (210) of the substrate (200).

6. The pole piece preparation apparatus according to any one of claims 2-5, characterized in that, Multiple blowing assemblies (150) are spaced apart in the baking assembly (140), the blowing assembly (150) has a blowing port, the blowing port faces the coating surface (210) of the substrate (200), and the blowing assembly (150) and the magnetization assembly (130) are arranged in a staggered manner relative to the thickness direction of the substrate (200).

7. The pole piece preparation apparatus of claim 6, wherein The blowing assembly (150) includes an upper blowing component (151) and a lower blowing component (152), along the thickness direction of the substrate (200), the upper blowing component (151) and the lower blowing component (152) are arranged on opposite sides of the baking assembly (140), and the upper blowing component (151) and the lower blowing component (152) respectively have the blowing port. The magnetizing assembly (130) and the upper blowing piece (151) are arranged in a staggered manner relative to the thickness direction of the base material (200); And / or, the magnetizing assembly (130) and the lower blowing piece (152) are arranged in a staggered manner relative to the thickness direction of the base material (200); And / or, the upper blowing piece (151) and the lower blowing piece (152) are arranged in a staggered manner relative to the thickness direction of the base material (200).

8. The pole piece preparation apparatus according to any one of claims 1-5, wherein, Further comprising a lifting piece connected to the magnetizing assembly (130), the lifting piece being used to drive the lifting of the magnetizing assembly (130); The pole piece preparation device further comprises a translation piece connected to the magnetizing assembly (130), the translation piece being used to drive the horizontal movement of the magnetizing assembly (130).

9. The pole piece preparation apparatus according to any one of claims 1-5, wherein, Further comprising an angle adjusting piece for adjusting the angle between the magnetizing assembly (130) and the plane of the base material (200).

10. The pole piece preparation apparatus of claim 8, wherein Further comprising a power supply piece (160) electrically connected to the lifting piece and the translation piece respectively, the power supply piece (160) being used to supply power to the lifting piece and the translation piece; The pole piece preparation device further comprises a control piece (170) electrically connected to the lifting piece and the translation piece respectively, the control piece (170) being used to control the lifting of the lifting piece and the translation of the translation piece.

11. The pole piece preparation apparatus of claim 10, wherein Further comprising a magnetic induction piece provided on the magnetizing assembly (130), the magnetic induction piece being electrically connected to the control piece (170), the magnetic induction piece being used to induce the magnetic field strength of the magnetizing assembly (130) and send the magnetic field strength to the control piece (170); And / or, the pole piece preparation device further comprises a magnetic shielding protection piece provided on the magnetizing assembly (130).

12. The pole piece preparation apparatus of any one of claims 2-5, wherein, Along the thickness direction of the base material (200), the distance between the magnetizing assembly (130) and the surface of the base material (200) is not greater than 2mm; And / or, the length of the baking assembly (140) is 2 times the length of the base material (200) moving at a preset speed within a preset time.

13. The pole piece preparation apparatus of any one of claims 3-5, wherein, The first magnetizing piece (131) is a permanent magnet or an electromagnet, the magnetic field strength of the first magnetizing piece (131) ranges from 0.4T to 2T, the magnetic field width of the first magnetizing piece (131) ranges from 150mm to 1500mm, and the magnetic field length of the first magnetizing piece (131) ranges from M / 5n; And / or, the second magnetizing piece (132) is a permanent magnet, the magnetic field strength of the second magnetizing piece (132) ranges from 0.4T to 2T, the magnetic field width of the second magnetizing piece (132) ranges from 150mm to 1500mm, and the magnetic field length of the second magnetizing piece (132) ranges from M / 5n; Wherein, M is the moving speed of the base material (200) in m / min, and n is the number of magnetizing assemblies (130).

14. A method of manufacturing a pole piece using the pole piece manufacturing apparatus according to any one of claims 1 to 13, characterized by, The pole piece preparation method comprises: feeding a substrate (200) into a transport assembly (110) and moving the substrate (200); coating a slurry on a coated surface (210) of the substrate (200) by a coating assembly (120); primary magnetizing particles in the slurry by a magnetizing assembly (130); secondary magnetizing the particles in the primary magnetized slurry by the magnetizing assembly (130), and baking the magnetized substrate (200) by a baking assembly (140).

15. The pole piece manufacturing method according to claim 14, wherein baking the magnetized substrate (200) by the baking assembly (140), comprising: primary baking the substrate (200) after the primary magnetizing and before the secondary magnetizing by the baking assembly (140); secondary baking the substrate (200) after the secondary magnetizing and the primary baking by the baking assembly (140).

16. A pole piece characterized by, The pole piece is prepared by the pole piece preparation method in claim 14, or the pole piece is prepared by the pole piece preparation device in any one of claims 1-13.

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