Metering extrusion film forming method and metering extrusion film forming device

Abstract

The invention discloses a metering extrusion film forming method and a metering extrusion film forming device. The metering extrusion film forming method comprises the steps that a feeding box is provided, the feeding box is filled with pole piece material powder, and the feeding box is provided with a discharging channel; a material receiving surface is provided, and a gap M is formed between the material receiving surface and the discharging channel; and performing ultrasonic vibration extrusion on the pole piece material powder by using an ultrasonic vibration head, so that the pole piece material powder is extruded to the material receiving surface from the discharging channel, and the pole piece material powder forms a film on the material receiving surface. By means of the ultrasonic vibration extrusion effect of the ultrasonic vibration head, pole piece material powder can be compacted in a vibration mode and extruded out of the discharging channel, and after being extruded out, the pole piece material powder reaches the material receiving face and can form a film on the material receiving face. By controlling the gap M between the material receiving surface and the discharging channel, the film forming thickness can be controlled, the accurate adjustment of the film forming thickness of the pole piece material powder is realized, and the control accuracy of the film forming thickness is improved. On the other hand, the situation that an extrusion roller is adopted for thinning the material powder film subsequently is avoided, and the manufacturing efficiency of the dry-method electrode is improved.

Description

Technical Field

[0001] The present application relates to the technical field of battery manufacturing, and in particular to a metering extrusion film-forming method and a metering extrusion film-forming device. Background Art

[0002] In the manufacturing process of the battery electrode sheet, it is necessary to use an adhesive to bond the active material to the foil of the electrode sheet, which includes dry process and wet process. Among them, the wet process requires coating the adhesive solvent on the foil first, and then coating the active material. Subsequently, the electrode sheet needs to be baked and the adhesive solvent needs to be recovered. This not only has the problems of complicated process flow and large land occupation of production equipment, but also consumes a lot of energy during the baking process. In comparison, the dry process has the advantages of simple process flow, high manufacturing efficiency, low energy consumption, and avoidance of the use of adhesive solvents.

[0003] In the related technology, the dry process does not use liquid binders to disperse the active materials, but first mixes the active materials, conductive agents, binders and other substances together, and then forms a film on the foil by rolling. However, this film forming method is difficult to control the film thickness, and it is necessary to use multiple rollers to press thinner later, which is not conducive to improving manufacturing efficiency. Summary of the invention

[0004] In order to solve at least one of the above technical problems, the present application provides a metering extrusion film-forming method and a metering extrusion film-forming device, which can accurately control the extrusion film thickness of the pole piece powder. The technical solution adopted is as follows.

[0005] In a first aspect, the metered extrusion film forming method provided by the present application comprises:

[0006] Providing a feed box, the feed box is filled with pole piece powder, and the feed box is provided with a discharge channel;

[0007] Providing a material receiving surface, wherein a gap M is provided between the material receiving surface and the material discharging channel;

[0008] An ultrasonic vibrator is used to perform ultrasonic vibration extrusion on the pole piece powder, so that the pole piece powder is squeezed out from the discharge channel to the receiving surface, and the pole piece powder is formed into a film on the receiving surface.

[0009] In certain embodiments of the first aspect of the present application, the length of the discharge channel is H and the width is L, and providing the feed box includes:

[0010] At least one of the length H or the width L of the discharge channel is adjusted to adjust the extrusion density of the pole piece powder.

[0011] In certain embodiments of the first aspect of the present application, the material receiving surface is arranged on the surface of the supporting roller, and before the pole piece powder is extruded from the discharge channel to the material receiving surface, and / or while the pole piece powder is extruded from the discharge channel to the material receiving surface, the metering extrusion film forming method further comprises:

[0012] heating the support roller; or

[0013] The support roll is cooled.

[0014] In certain embodiments of the first aspect of the present application, the metering extrusion film forming method further comprises:

[0015] Providing a vacuum environment so that the ultrasonic vibration die head vibrates and extrude the pole piece powder in the vacuum environment, so that the pole piece powder is extruded from the discharge channel to the receiving surface; or

[0016] A pressurized environment is provided so that the ultrasonic vibration die head vibrates and extrude the pole piece powder under the pressurized environment, so that the pole piece powder is extruded from the discharge channel to the receiving surface.

[0017] In certain embodiments of the first aspect of the present application, the material receiving surface is arranged on the surface of a support roller, a pole piece is wound around the surface of the support roller, and the pole piece powder is extruded from the discharge channel to the material receiving surface, comprising:

[0018] The electrode material powder is extruded from the discharge channel to the electrode surface;

[0019] The supporting roller is rotated to move the pole piece relative to the discharge channel.

[0020] In certain embodiments of the first aspect of the present application, the material receiving surface is disposed on the surface of the transfer roller, and the pole piece powder is extruded from the discharge channel to the material receiving surface, comprising:

[0021] The pole piece powder is extruded from the discharge channel to the surface of the transfer roller;

[0022] A pole piece is arranged downstream of the transfer roller, and the pole piece abuts against the surface of the transfer roller;

[0023] The transfer roller is rotated to transfer the film-forming pole piece powder from the surface of the transfer roller to the surface of the pole piece.

[0024] In a second aspect, the present application provides a metering extrusion film-forming device, which is used to implement the metering extrusion film-forming method provided in the first aspect, and the metering extrusion film-forming device comprises:

[0025] A feed box, wherein the feed box is provided with a material storage space and a material discharge channel which are interconnected, and either the material discharge space or the material discharge channel is provided with an extrusion port, and the extrusion port is connected to the outlet of the material discharge channel;

[0026] A material receiving surface is arranged at the outlet of the material discharging channel, and a gap M is formed between the material receiving surface and the outlet of the material discharging channel;

[0027] The ultrasonic vibration head is arranged at the extrusion port.

[0028] In certain embodiments of the second aspect of the present application, the storage space includes at least two storage troughs, which are arranged obliquely relative to the discharge channel and connected to the discharge channel, and the two storage troughs are symmetrically arranged about the discharge channel.

[0029] In certain embodiments of the second aspect of the present application, the metering extrusion film-forming device also includes a support roller, which is arranged at the outlet of the discharge channel and spaced apart from the outlet of the discharge channel, and the surface of the support roller forms the material receiving surface.

[0030] In certain embodiments of the second aspect of the present application, a heat exchange channel is provided in the support roller, and the heat exchange channel is used to pass a heat exchange medium.

[0031] The embodiments of the present application have at least the following beneficial effects: by utilizing the ultrasonic vibration extrusion effect of the ultrasonic vibrator, the electrode sheet powder can be vibrated and compacted and extruded from the discharge channel. After being extruded, the electrode sheet powder reaches the receiving surface and can form a film on the receiving surface. By controlling the gap M between the receiving surface and the discharge channel, the thickness of the film can be controlled. On the one hand, the thickness of the film of the electrode sheet powder can be accurately adjusted by adjusting the gap M, so as to meet the process requirements of dry electrode manufacturing and improve the accuracy of film thickness control. On the other hand, it avoids the subsequent use of an extrusion roller to thin the powder film, thereby improving the manufacturing efficiency of the dry electrode. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The aspects and advantages described and / or attached in the embodiments of the present application will become apparent and easy to understand in conjunction with the following drawings. It should be noted that the embodiments embodied in the following drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0033] Figure 1 A schematic structural diagram of a first example of a metering extrusion film-forming device provided in an embodiment of the present application;

[0034] Figure 2 for Figure 1 A local enlarged view of point A;

[0035] Figure 3 A schematic structural diagram of a second example of a metering extrusion film-forming device provided in an embodiment of the present application;

[0036] Figure 4A schematic structural diagram of a third example of a metering extrusion film-forming device provided in an embodiment of the present application;

[0037] Figure 5 This is a flow chart of the metered extrusion film-forming method provided in an embodiment of the present application.

[0038] Figure numerals: 100, metering extrusion film-forming device; 10, feed box; 11, storage space; 111, storage trough; 112, extrusion port; 12, discharge channel; 20, material receiving surface; 30, ultrasonic vibrator; 31, ultrasonic transducer; 32, ultrasonic amplitude transformer; 33, fixed bracket; 40, support roller; 41, heat exchange channel; 50, movable bracket; 200, pole piece powder. DETAILED DESCRIPTION

[0039] Combine the following Figures 1 to 5 Embodiments of the present application are described in detail, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0040] In the description of the present application, it should be understood that if the terms "center", "middle", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like appear, the orientation or position relationship indicated is based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, unless otherwise specified, "multiple" means two or more.

[0041] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0042] First, see Figures 1 to 4The present application provides a metering extrusion film-forming device 100, which can realize the metering extrusion of the pole piece powder 200, so as to accurately control the extrusion film thickness of the pole piece powder 200. The metering extrusion film-forming device 100 includes a feed box 10, a material receiving surface 20 and an ultrasonic vibrator 30. The feed box 10 is provided with a storage space 11 and a discharge channel 12 which are interconnected, and either the discharge space or the discharge channel 12 is provided with an extrusion port 112, which is connected to the outlet of the discharge channel 12. The material receiving surface 20 is arranged at the outlet of the discharge channel 12, and a gap M is formed between the material receiving surface 20 and the outlet of the discharge channel 12, and the ultrasonic vibrator 30 is arranged at the extrusion port 112.

[0043] By utilizing the ultrasonic vibration extrusion effect of the ultrasonic vibrator 30 at the extrusion port 112, the pole piece powder 200 can be vibrated and compacted and extruded from the outlet of the discharge channel 12. After being extruded, the pole piece powder 200 reaches the material receiving surface 20 and can form a film on the material receiving surface 20. By controlling the gap M between the material receiving surface 20 and the discharge channel 12, the thickness of the film can be controlled. At the same time, the density of the film can also be adjusted by controlling the length H and width L of the discharge channel 12. Therefore, using the three parameters of the length H, width L and gap M of the discharge channel 12, the film density and film thickness of the pole piece powder 200 can be metered and controlled to meet the process requirements. In this way, the pole piece powder 200 can meet the pole piece production requirements after one extrusion film, and there is no need for secondary rolling thinning, which helps to improve manufacturing efficiency.

[0044] For example, see Figure 3 , the gap M can be achieved by adjusting the relative position between the feed box 10 and the material receiving surface 20. For example, by setting the feed box 10 on the movable bracket 50, and by adjusting the height position of the extrusion mechanism 100 on the movable bracket 50, the relative position between the feed box 10 and the material receiving surface 20 can be adjusted. For example, the material receiving surface 20 can remain stationary in the vertical direction, and the feed box 10 is set above the material receiving surface 20. When the feed box 10 is adjusted on the movable bracket 50, the gap M increases, and when the feed box 10 is adjusted down on the movable bracket 50, the gap M decreases. It can be understood that before using the feed box 10, the gap M can be adjusted according to the process requirements, and the gap M is no longer adjusted during the use of the feed box 10, ensuring that the feed box 10 has a stable gap M during the discharge process, so that the pole piece powder 200 has a uniform film thickness after extrusion. Of course, in other examples, the gap M can also be adjusted by adjusting the position of the material receiving surface 20 up and down, which is not limited here.

[0045] Optionally, see Figure 3 and Figure 4The ultrasonic vibrator 30 can also be installed by using a fixing bracket 33, and can be connected to the ultrasonic transducer 31 and the ultrasonic horn 32 in sequence, and the ultrasonic vibrator 30 can be driven by using the ultrasonic transducer 31 and the ultrasonic horn 32. The fixing bracket 33 can fix the ultrasonic horn 32, so as to adjust the gap between the ultrasonic vibrator 30 and the feed box 10.

[0046] In some embodiments, the storage space 11 includes at least two storage troughs 111, which are arranged obliquely relative to the discharge channel 12 and are connected to the discharge channel 12, and the two storage troughs 111 are arranged symmetrically about the discharge channel 12. By using the obliquely arranged storage troughs 111, the pole piece powder 200 can fall freely under the action of gravity and smoothly move to the position of the discharge channel 12, thereby realizing continuous feeding to the discharge channel 12. By using the symmetrically arranged storage troughs 111, on the one hand, it is possible to realize simultaneous feeding on both sides of the discharge channel 12, thereby improving the feeding efficiency of the discharge channel 12, and on the other hand, it is possible to ensure the uniformity of feeding from the storage troughs 111 on both sides, thereby ensuring that the discharge channel 12 can discharge smoothly.

[0047] In some embodiments, the metering extrusion film forming device 100 further includes a support roller 40, which is disposed at the outlet of the discharge channel 12 and is spaced apart from the outlet of the discharge channel 12, and the surface of the support roller 40 forms a material receiving surface 20. By providing the support roller 40, the pole piece receiving the powder 200 can be supported, so as to avoid the fluctuation of the size of the gap M caused by the shaking of the pole piece when coating the powder 200, and avoid the problem of uneven film thickness. Therefore, providing the material receiving surface 20 on the support roller 40 can improve the stability and reliability of the pole piece powder 200 during the extrusion film forming process, make the film thickness more uniform, and improve the effect of pole piece manufacturing.

[0048] Optionally, the support roller 40 can be made of alloy steel material, so that the support roller 40 has sufficient strength and rigidity to provide good support for the pole piece. The surface roughness of the support roller 40 can be set to Ra12.5-6.3, so that when the pole piece is wound on the surface of the support roller 40, there can be good friction between the two, so that the support roller 40 can provide sufficient tension to the pole piece, so that the pole piece surface can be kept flat, ensuring that the pole piece material powder extruded into a film can be evenly coated on the pole piece surface.

[0049] In some embodiments, a heat exchange channel 41 is provided in the support roller 40, and the heat exchange channel 41 is used to pass a heat exchange medium. Passing a hot medium (such as heat transfer oil) into the heat exchange channel 41 can increase the temperature of the support roller 40, and passing a cold medium (such as coolant) into the heat exchange channel 41 can reduce the temperature of the support roller 40. According to the film forming temperature requirements, different heat exchange media can be selectively passed into the heat exchange channel 41 to meet the process requirements of temperature control during the film forming process. For example, for the binder particles mixed in the pole piece powder 200, the binder particles usually denature under high temperature conditions and become sticky. Therefore, by heating the support roller 40, the pole piece powder 200 can be made sticky during the process of extruding to the material receiving surface 20 to form a film, meeting the process requirements. Or in other examples, if it is necessary to avoid the stickiness of the binder particles during the extrusion film forming process of the pole piece powder 200, the support roller 40 is cooled and cooled to avoid the stickiness of the pole piece powder too early.

[0050] Optionally, the heat exchange channel 41 may be arranged to extend along the axial direction of the support roller 40 and pass through the two end surfaces of the support roller 40. Of course, in other examples, the support roller 40 may be heated not by a heat exchange medium, but by an electric heating tube or an electromagnetic coil.

[0051] Second, see Figure 5 The present application provides a metering extrusion film forming method, which can be implemented using the metering extrusion film forming device 100 provided in the first aspect. The metering extrusion film forming method includes the following steps:

[0052] S100 provides a feed box 10, the feed box 10 is filled with a pole piece powder 200, the feed box 10 is provided with a discharge channel 12;

[0053] S200 provides a material receiving surface 20, and a gap M is provided between the material receiving surface 20 and the discharge channel 12;

[0054] S300 . Use the ultrasonic vibrator 30 to perform ultrasonic vibration extrusion on the pole piece powder 200 , so that the pole piece powder 200 is squeezed out from the discharge channel 12 to the receiving surface 20 , and the pole piece powder 200 forms a film on the receiving surface 20 .

[0055] By setting a feed box 10 and filling the pole piece powder 200 in the feed box 10, the pole piece powder 200 can be extruded by using the discharge channel 12 of the feed box 10. Optionally, the pole piece powder 200 refers to the active material, conductive agent, solid binder and other substances after mixing, and these substances are mixed in powder form to form a uniform and stable pole piece powder 200. The receiving surface 20 refers to the surface for receiving the pole piece powder 200, which can be a flat surface or a curved surface. The receiving surface 20 can be the surface of the pole piece, that is, the pole piece powder 200 can be directly extruded from the discharge channel 12 onto the pole piece to complete the coating of the pole piece powder 200. Or in other examples, the pole piece powder 200 does not fall directly on the pole piece surface, but forms a film on the surface of the transfer roller (not shown), and then the film formed by the powder 200 is transferred to the pole piece by the transfer roller, which is not limited here. It is understandable that step S100 and step S200 can be performed simultaneously, or step S200 can be performed first and then step S100, which is not limited here. Optionally, the extruded film-forming electrode sheet powder 200 can be further heated and extruded in subsequent processes to improve the viscosity, density or stability of the electrode sheet powder 200 itself, which depends on the process requirements and is not limited in this example.

[0056] By utilizing the ultrasonic vibration extrusion effect of the ultrasonic vibrator 30, the pole piece powder 200 can be vibrated and compacted and squeezed out from the discharge channel 12. After being extruded, the pole piece powder 200 reaches the material receiving surface 20 and can form a film on the material receiving surface 20. There is a certain bonding force between the film-forming pole piece powder 200 and the material receiving surface 20 to preliminarily fix it on the material receiving surface 20. By controlling the gap M between the material receiving surface 20 and the discharge channel 12, the thickness of the film can be controlled. For example, when the gap M is increased, the film thickness increases, and when the gap M is reduced, the film thickness decreases. On the one hand, the thickness of the film of the pole piece powder 200 can be accurately adjusted by adjusting the gap M, so as to meet the process requirements of dry electrode manufacturing and improve the accuracy of film thickness control. On the other hand, it avoids the subsequent use of an extrusion roller to thin the powder 200 film, thereby improving the manufacturing efficiency of the dry electrode.

[0057] Optionally, the working frequency of the ultrasonic vibrator 30 can be 15KHz to 20KHz, such as 15KHz, 16KHz, 18KHz, 20KHz, etc. The energy generated by ultrasonic vibration can compact the pole piece powder 200 and improve the density of the pole piece powder 200, thereby achieving the effect of forming a film of the pole piece powder 200.

[0058] In addition to controlling the film thickness, the density of the film can also be adjusted at the same time. In some embodiments, the length of the discharge channel 12 is H and the width is L. The above step S100. providing the feed box 10 includes:

[0059] S110 . Adjust at least one of the length H of the discharge channel 12 or the width L of the discharge channel 12 to adjust the extrusion density of the pole piece powder 200 .

[0060] By adjusting the length H of the discharge channel 12, the resistance of the pole piece powder 200 in the discharge channel 12 can be adjusted. For example, when the length H is increased, the discharge resistance increases, and the film density can be improved at this time. When the length H is reduced, the discharge resistance decreases, thereby reducing the film density. By adjusting the width L of the discharge channel 12, the discharge amount per unit length can be changed. For example, when the width L is increased, the discharge amount per unit length can be increased, thereby improving the film density. When the width L is reduced, the discharge amount can be reduced, thereby reducing the film density. It can be seen that by controlling the length H and width L of the discharge channel 12 separately, the film density of the pole piece powder 200 can be adjusted to meet the process requirements. It can be understood that the length H and width L of the discharge channel 12 can be adjusted separately or simultaneously to achieve accurate control of the film density. Therefore, the three parameters of the length H, width L and gap M of the discharge channel 12 can be used to measure and control the film density and film thickness of the pole piece powder 200. This means that the length H, width L and gap M of the discharge channel 12 can be selected and controlled according to the process requirements of film density and film thickness, thereby improving the film quality and effect. In this way, the pole piece material powder 200 can meet the pole piece production requirements after one extrusion film formation, without the need for secondary rolling thinning, which helps to improve manufacturing efficiency.

[0061] It is understandable that, for the same feed box 10, the length H and width L of the discharge channel 12 of the feed box 10 can be fixed, so the discharge channel 12 with different lengths H or widths L can be obtained by selecting feed boxes 10 of different specifications or selecting accessories of the discharge channel 12 of different specifications. Of course, in other examples, the feed box 10 can adjust the width L by adjusting the spacing between the two side walls of the discharge channel 12, or adjust the length H by adjusting the distance between the inlet and outlet ends of the discharge channel 12, which means that the components inside the feed box 10 can be set as movable parts, so as to adjust the length H and width L of the discharge channel 12 by moving the movable components, which is not limited here.

[0062] In some embodiments, the metered extrusion film forming method further comprises the following steps:

[0063] S400 provides a vacuum environment so that the ultrasonic vibration die head vibrates and extrude the pole piece powder 200 under a vacuum environment so that the pole piece powder 200 is extruded from the discharge channel 12 to the receiving surface 20; or

[0064] S500 . Provide a pressurized environment so that the ultrasonic vibration die head vibrates and extrude the pole piece powder 200 under the pressurized environment, so that the pole piece powder 200 is squeezed out from the discharge channel 12 to the receiving surface 20 .

[0065] In a vacuum environment, low-pressure film-forming conditions can be provided for the extrusion of the pole piece powder 200, meeting the requirements of extruding the pole piece powder 200 into a film under low-pressure conditions. Similarly, in a pressurized environment, high-pressure film-forming conditions can be provided for the extrusion of the pole piece powder 200, which helps to increase the density of the extruded film of the pole piece powder 200. It can be understood that the above steps S400 and S500 are implemented one by one according to the process requirements.

[0066] In some embodiments, the material receiving surface 20 is disposed on the surface of the support roller 40, and the surface of the support roller 40 is wound with a pole piece. The above step S300. The pole piece powder 200 is extruded from the discharge channel 12 to the material receiving surface 20 includes:

[0067] S311. The pole piece powder 200 is extruded from the discharge channel 12 to the pole piece surface;

[0068] S312. Rotate the support roller 40 to move the pole piece relative to the discharge channel 12.

[0069] By setting the support roller 40, the pole piece receiving the powder 200 can be supported to avoid the fluctuation of the size of the gap M caused by the shaking of the pole piece when coating the powder 200, and avoid the problem of uneven film thickness. Therefore, setting the material receiving surface 20 on the support roller 40 can improve the stability and reliability of the pole piece powder 200 in the process of extruding the film, making the film thickness more uniform, and improving the effect of pole piece manufacturing. Utilizing the supporting effect of the support roller 40, the pole piece can be driven to move relative to the discharge channel 12, and the pole piece can be moved while the pole piece powder 200 is extruded through the discharge channel 12, so that the pole piece powder 200 extruded into the film can be coated on the pole piece surface along the moving direction of the pole piece. Optionally, the moving speed of the pole piece can be adjusted by controlling the rotation speed of the support roller 40, and the moving speed of the pole piece is adjusted to be consistent with the extrusion speed of the pole piece powder 200, so as to ensure that the pole piece powder 200 can be uniformly filmed on the pole piece surface, avoiding the accumulation or discontinuity of the pole piece powder 200.

[0070] In some embodiments, the electrode sheet powder 200 may not be directly formed on the electrode sheet surface, but may be transferred by a transfer roller. Specifically, the material receiving surface 20 is set on the surface of the transfer roller (not shown). The above step S300. The electrode sheet powder 200 is extruded from the discharge channel 12 to the material receiving surface 20 includes:

[0071] S321. The pole piece powder 200 is extruded from the discharge channel 12 to the surface of the transfer roller;

[0072] S322. Arrange a pole piece downstream of the transfer roller, the pole piece abutting against the surface of the transfer roller;

[0073] S323. Rotate the transfer roller to transfer the film-forming electrode sheet powder 200 from the surface of the transfer roller to the surface of the electrode sheet.

[0074] By utilizing the transfer function of the transfer roller, when the pole piece powder 200 is extruded from the discharge channel 12, it can first form a film on the surface of the transfer roller, and then when the transfer roller rotates to contact the pole piece, the pole piece powder 200 formed on the transfer roller surface can be transferred to the pole piece surface, achieving the effect of coating the pole piece surface with the powder 200. By setting the transfer roller, it is possible to avoid the fluctuation of the size of the gap M caused by the direct shaking of the pole piece when coating the powder 200, and avoid the problem of uneven film thickness. Therefore, setting the material connection surface 20 on the transfer roller can improve the stability and reliability of the pole piece powder 200 in the process of extruding and filming, make the film thickness more uniform, and improve the effect of pole piece manufacturing.

[0075] Of course, as an alternative embodiment, the receiving surface 20 can also be directly set on the pole piece, and the pole piece is set corresponding to the outlet of the discharge channel 12. Tensioning rollers can be provided at both ends of the pole piece for tensioning, so that the surface of the pole piece has a certain tension, and the amplitude of the pole piece vibration is reduced during the process of extruding the pole piece powder 200 in the discharge channel 12, so that the process of extruding the pole piece powder 200 into a film is more stable.

[0076] Alternatively, as another alternative embodiment, the material connection surface 20 can be directly set on the pole piece, and the pole piece is supported by a structure such as a conveyor belt or a conveyor support block, and the material connection surface 20 can be a plane. This can also meet the requirements of pole piece stability and achieve the effect of pole piece movement during the extrusion of the pole piece material powder 200, which is not limited in this application.

[0077] In order to meet the temperature condition requirements of different pole piece powders 200 during extrusion film forming, in some embodiments, the material receiving surface 20 is set on the surface of the support roller 40, before the pole piece powder 200 is extruded from the discharge channel 12 to the material receiving surface 20 in step S300, or while the pole piece powder 200 is extruded from the discharge channel 12 to the material receiving surface 20 in step S300, the metering extrusion film forming method further includes:

[0078] S330. Heating the support roller 40; or

[0079] S340. Cool the support roller 40.

[0080] For the binder particles mixed in the pole piece powder 200, the binder particles will usually be denatured in a high temperature environment and become sticky. Therefore, by heating the support roller 40, the pole piece powder 200 can be made sticky during the process of being extruded to the receiving surface 20 to form a film, thereby meeting the process requirements. Or in other examples, if it is necessary to avoid the stickiness of the binder particles during the extrusion and film formation of the pole piece powder 200, the support roller 40 is cooled to avoid the stickiness of the pole piece powder too early. It can be seen that according to the process requirements of different products, the temperature of the support roller 40 can be controlled to meet the needs of the pole piece powder 200 during the extrusion and film formation process.

[0081] It is understandable that the above steps S330 and S340 are implemented one by one according to the process requirements. Optionally, both the heating and cooling operations of the support roller 40 can be performed before the extrusion of the pole piece powder 200, or can be continued throughout the entire process of extruding the pole piece powder 200 into a film. Of course, heating or cooling can also be performed only during the extrusion of the pole piece powder 200, which is not limited here.

[0082] In the description of this specification, if the reference terms "one embodiment", "some examples", "some embodiments", "illustrative embodiment", "example", "specific example", or "some examples" appear, it means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0083] The above describes the implementation methods of the present application in detail in conjunction with the accompanying drawings, but the present application is not limited to the above implementation methods. Various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present application.

[0084] In the description of this application, if "," appears in the patent name, it means an "and" relationship, not an "or" relationship. For example, if the patent name is "a kind of A, B", it means that the content required to be protected by this application is: the technical solution with the subject name A and the technical solution with the subject name B.

Claims

1. A metering extrusion film forming method, characterized in that: include Providing a feed box, the feed box is filled with pole piece powder, and the feed box is provided with a discharge channel; Providing a material receiving surface, wherein a gap M is provided between the material receiving surface and the material discharging channel; An ultrasonic vibrator is used to perform ultrasonic vibration extrusion on the pole piece powder, so that the pole piece powder is squeezed out from the discharge channel to the receiving surface, and the pole piece powder is formed into a film on the receiving surface.

2. The method for forming a film by metering extrusion according to claim 1, characterized in that: The length of the discharge channel is H, and the width is L. The feed box provided includes: At least one of the length H or the width L of the discharge channel is adjusted to adjust the extrusion density of the pole piece powder.

3. The metering extrusion film forming method according to claim 1, characterized in that: The receiving surface is arranged on the surface of the supporting roller, and before the pole piece powder is extruded from the discharge channel to the receiving surface, and / or while the pole piece powder is extruded from the discharge channel to the receiving surface, the metering extrusion film forming method further comprises: heating the support roller; or The support roll is cooled.

4. The method for forming a film by metering extrusion according to claim 1, characterized in that: The metering extrusion film forming method also includes: Providing a vacuum environment so that the ultrasonic vibration die head vibrates and extrude the pole piece powder in the vacuum environment so that the pole piece powder is extruded from the discharge channel to the receiving surface; or A pressurized environment is provided so that the ultrasonic vibration die head vibrates and extrude the pole piece powder under the pressurized environment, so that the pole piece powder is extruded from the discharge channel to the receiving surface.

5. The metering extrusion film forming method according to claim 1, characterized in that: The material receiving surface is arranged on the surface of the support roller, a pole piece is wound around the surface of the support roller, and the pole piece powder is extruded from the discharge channel to the material receiving surface, which includes: The electrode material powder is extruded from the discharge channel to the electrode surface; The supporting roller is rotated to move the pole piece relative to the discharge channel.

6. The method for forming a film by metering extrusion according to claim 1, characterized in that: The material receiving surface is arranged on the surface of the transfer roller, and the pole piece powder is extruded from the discharge channel to the material receiving surface, comprising: The pole piece powder is extruded from the discharge channel to the surface of the transfer roller; A pole piece is arranged downstream of the transfer roller, and the pole piece abuts against the surface of the transfer roller; The transfer roller is rotated to transfer the film-forming pole piece powder from the surface of the transfer roller to the surface of the pole piece.

7. A metering extrusion film forming device, characterized in that: The metering extrusion film-forming device is used to implement the metering extrusion film-forming method according to any one of claims 1 to 6, and the metering extrusion film-forming device comprises: A feed box, wherein the feed box is provided with a material storage space and a material discharge channel which are interconnected, and either the material discharge space or the material discharge channel is provided with an extrusion port, and the extrusion port is connected to the outlet of the material discharge channel; A material receiving surface is arranged at the outlet of the material discharging channel, and a gap M is formed between the material receiving surface and the outlet of the material discharging channel; The ultrasonic vibration head is arranged at the extrusion port.

8. The metering extrusion film forming device according to claim 7, characterized in that: The material storage space includes at least two material storage troughs, which are arranged obliquely relative to the material discharge channel and are connected to the material discharge channel, and the two material storage troughs are arranged symmetrically with respect to the material discharge channel.

9. The metering extrusion film forming device according to claim 7, characterized in that: The metering extrusion film-forming device further comprises a support roller, which is arranged at the outlet of the discharge channel and spaced apart from the outlet of the discharge channel, and the surface of the support roller forms the material receiving surface.

10. The extrusion film forming device according to claim 9, characterized in that: The support roller is provided with a heat exchange channel, and the heat exchange channel is used to pass a heat exchange medium.

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