A lithium battery pole piece coating device

Abstract

The utility model discloses a kind of lithium battery pole piece coating devices, including base, synchronous rotation's coating roller, driving motor, guide roller, vertical fixed plate, back roller and adjusting mechanism. Its innovation is in: the position of back roller is accurately controlled by screw rod-U-shaped groove guide's lifting mechanism, in combination with high-precision laser displacement sensor real-time monitoring guide roller displacement, realize coating gap closed-loop control;Heating device is set in back roller, and heating wire and temperature control system are communicated by swivel joint, to realize substrate active preheating;Additional elastic damping component is added between bearing seat and U-shaped groove to suppress vibration and stabilize position. The device solves the problems of uneven coating thickness, poor substrate wettability and vibration interference, and the coating thickness deviation is ≤1.5%.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery production, and in particular to a lithium battery electrode coating device. Background Technology

[0002] In the production process of lithium batteries, the manufacturing of electrode sheets plays a crucial role. Statistics show that approximately 70% of lithium battery quality problems are related to the quality of the electrode sheets. The manufacturing process of lithium battery electrode sheets includes steps such as slurry mixing, coating, drying, rolling, and cutting. Common defects in electrode sheets include agglomerates, pinholes, and scratches and streaks caused by uneven coating. Among these defects, the main cause of agglomerates is uneven slurry mixing, leading to the formation of conductive agent agglomerates on the electrode sheet surface after coating. In current lithium battery electrode coating processes, coating thickness consistency, substrate tension stability, and drying efficiency directly affect battery performance. Traditional coating equipment suffers from the following defects: Insufficient coating gap precision: The mechanical manual adjustment of the back roller height is prone to gap deviation due to vibration, making it difficult to achieve μm-level precision control, resulting in uneven coating thickness on the electrode sheets; Lack of substrate preheating: The cold substrate has poor wettability after contacting the slurry, which easily produces bubbles and streaks, requiring extended drying time and increased energy consumption; Lack of dynamic monitoring: There is no real-time feedback mechanism for the coating gap, making it impossible to correct deviations online, resulting in unstable product yield; Back roller vibration interference: During equipment operation, the back roller is subjected to transmission impact, and the traditional rigid support causes periodic ripples in the coating.

[0003] Existing technologies, such as CN202010668262.0, disclose a fuel cell membrane electrode coating and feeding device and method. This method utilizes a low-temperature constant-temperature bath and refrigerant to cool the slurry, maintaining a high viscosity and low flowability to reduce bubble formation and improve coating uniformity. The solutions disclosed in these patent documents can solve most of the bubble problems generated during slurry stirring and coating. However, they lack a real-time feedback mechanism for coating gaps, making online correction of deviations impossible and resulting in unstable product yield. Utility Model Content

[0004] The technical problem to be solved by this utility model is to overcome the defects of the prior art and provide a lithium battery electrode coating device.

[0005] To solve the above-mentioned technical problems, this utility model provides the following technical solution:

[0006] This utility model discloses a lithium battery electrode coating device, comprising: a base with coating rollers that can rotate synchronously at both ends, the two coating rollers being linked by a transmission gear set; a drive motor whose output shaft is connected to the rotating shaft of any of the coating rollers or the transmission gear set; a guide roller arranged parallel to the feed side of the coating rollers; vertical fixing plates symmetrically fixed on both sides of the base; a back roller rotatably supported between the two vertical fixing plates by bearing seats; and an adjustment mechanism including a U-shaped guide groove formed on the inner side of the vertical fixing plate, located on both sides of the bearing seats and connected to the U-shaped guide groove. The sliding block with groove sliding fit has an adjusting screw fixed at the bottom end to the top of the bearing seat, a U-shaped fixed seat installed at the top of the vertical fixed plate, and lifting drive devices located at both ends of the U-shaped fixed seat, the output end of which is connected to the top of the adjusting screw for transmission; the feeding trough is built into the lower part of the base and connected to the slurry nozzle above the coating roller through a pump pipe; the heating device is connected to the end of the back roller through a rotary joint, and the heating wire of the heating device extends into the internal cavity of the back roller; high-precision laser displacement sensors are symmetrically arranged on opposite sides of the two vertical fixed plates, and their optical axis points to the axial center point of the guide roller.

[0007] As a preferred technical solution of this utility model, the lifting drive device includes a servo motor fixed to the outside of the U-shaped fixed base, and a bevel gear box with the input end connected to the output shaft of the servo motor and the output end extending downward. The output end is connected to the top of the adjusting screw through a coupling.

[0008] As a preferred embodiment of this utility model, the bevel gearbox contains a pair of orthogonally meshing bevel gears for converting horizontal rotational motion into vertical rotational motion.

[0009] As a preferred embodiment of this utility model, the heating device includes: a temperature sensor disposed inside the back roller, an electrical control box connected to the heating wire via a conductive slip ring, and a temperature controller that receives the temperature sensor signal and controls the operation of the electrical control box.

[0010] In a preferred embodiment of this invention, the back roller and the coating roller are arranged in parallel, forming an adjustable coating gap between them; the displacement signal detected by the high-precision laser displacement sensor is used to provide feedback and monitor the coating gap width of the guide roller relative to the vertical fixed plate.

[0011] As a preferred technical solution of this utility model, an elastic damping component is provided between the bearing seat and the U-shaped groove. The elastic damping component is sleeved on the outside of the slider and is used to provide buffering, shock absorption and positioning retention force when the bearing seat slides.

[0012] Compared with the prior art, the beneficial effects of this utility model are as follows:

[0013] 1. A closed-loop lifting mechanism consisting of a servo motor, bevel gearbox, and adjusting screw, combined with a U-shaped guide groove and slider for dual guidance, achieves a vertical displacement resolution of 0.5μm for the back roller, ensuring coating gap accuracy. A high-precision laser displacement sensor monitors the guide roller position deviation in real time, providing feedback to adjust the coating gap, eliminating cumulative errors, and ensuring thickness consistency deviation ≤1.5%.

[0014] 2. The built-in heating back roller directly conducts heat to the substrate, with a heating rate of up to 10℃ / s and a substrate surface temperature uniformity of ±2℃; after heating, the surface energy of the substrate is improved, the slurry spreading speed is increased by 40%, and bubble / stripe defects are eliminated.

[0015] 3. The elastic damping component absorbs high-frequency vibrations of the transmission system, reducing the amplitude of the back roller by more than 90% and eliminating coating periodic marks; the damping preload of the slider and the U-shaped groove prevents gap drift, and the gap fluctuation is <±10μm during continuous 8 hours of operation. Attached Figure Description

[0016] The accompanying drawings are provided to further illustrate the present invention and form part of the specification. They are used together with the embodiments of the present invention to explain the present invention, but do not constitute a limitation thereof. In the drawings:

[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0018] Figure 2 This is the front view of this utility model;

[0019] Figure 3 This is a top view of the present invention;

[0020] Figure 4 This is a side view of the present invention;

[0021] Figure 5 This is a cross-sectional structural diagram of the present invention;

[0022] In the diagram: 1. Base; 2. Coating roller; 3. Guide roller; 4. Vertical fixing plate; 5. Back roller; 6. Bearing seat; 7. Adjusting screw; 8. U-shaped fixing seat; 9. Lifting drive device; 10. Feeding trough; 11. Heating device; 12. Heating wire; 13. High-precision laser displacement sensor; 14. Servo motor; 15. Bevel gearbox; 16. Electrical control box; 17. Temperature sensor; 18. Temperature controller; 19. Drive motor; 20. Slider. Detailed Implementation

[0023] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0024] In the attached diagram, all identical reference numerals refer to the same components.

[0025] Example 1, as Figure 1-5 As shown, this utility model provides a lithium battery electrode coating device. Two coating rollers 2 are mounted on both ends of the top of the base 1 via bearing seats. The two rollers rotate synchronously in opposite directions via a transmission gear set (gear ratio 1:1). The output shaft of the drive motor 19 is connected to the rotating shaft of the right coating roller 2 via a reducer. A guide roller 3 is positioned parallel to the coating roller 2, 50mm in front of the feed side, to guide the copper foil substrate. Two vertical fixing plates 4 are vertically fixed to both sides of the base 1 using M16 anchor bolts, with a spacing error ≤0.05mm. A back roller 5 is supported between the vertical fixing plates 4 by bearing seats 6, which are double-row angular contact ball bearings.

[0026] The adjusting mechanism has a U-shaped guide groove machined on the inner side of the vertical fixed plate 4. A slider 20 is welded above the bearing seat 6, with a clearance fit ≤0.02mm with the U-shaped guide groove. The bottom end of the adjusting screw 7 is fixed to the top center of the bearing seat 6 with a set screw. The U-shaped fixed seat 8 is bolted to the top of the vertical fixed plate 4. The servo motors 14 in the lifting drive devices 9 on both sides are connected to a bevel gearbox 15. The bevel gear module is 2mm, the transmission ratio is 1:1, and the output end drives the adjusting screw 7 via a diaphragm coupling, achieving a lifting stroke of ±10mm for the back roller 5 and a displacement resolution of 0.5μm.

[0027] In Example 2, the heating device 11 is connected to the right end of the back roller 5 via a rotary joint, and the heating wire 12 extends into the spiral flow channel inside the back roller 5 (5mm from the roller surface). Temperature sensors 17 (PT100 platinum resistance thermometers) are embedded at three points (left, center, and right) within the inner cavity of the back roller 5, and their wires are connected to the control box 16 via conductive slip rings. The temperature controller 18 sets the surface temperature of the back roller to 60±5℃. High-precision laser displacement sensors 13 are symmetrically installed inside the vertical fixing plate 4, with a spot diameter of 0.2mm, aligned with the axial midpoint of the guide roller 3, and transmit the displacement signal in real time to the PLC to control the servo motor 14 to dynamically compensate for gap deviations.

[0028] The method of using this utility model is as follows:

[0029] 1. Start the temperature controller 18 and set the target temperature of the back roller 5 to 60℃ (the optimal temperature for copper foil wetting, as measured). The heating wire 12 is energized through the conductive slip ring, and the temperature sensor 17 feeds back data to the electrical control box 16 in real time, ensuring that the roller surface temperature uniformity is ≤±2℃. The servo motor 14 drives the bevel gear box 15 (horizontal → vertical rotation), which drives the adjusting screw 7 to rotate (lead 4mm), pushing the bearing seat 6 vertically downward along the U-shaped guide groove until the gap between the back roller 5 and the coating roller 2 reaches the initial value of 200μm. The elastic damping component is deformed by the pressure of the slider 20, providing preload to suppress shaking.

[0030] 2. Substrate insertion: The copper foil is tensioned and guided into the coating gap by the guide roller 3. The high-precision laser displacement sensor 13 monitors the displacement of the guide roller 3 in real time. If the position offset of the guide roller 3 is detected to be >10μm (such as due to substrate wrinkles), the PLC immediately controls the servo motor 14 to finely adjust the lead screw lifting to compensate for the gap.

[0031] 3. The coating roller 2 rotates synchronously through the transmission gear set. The slurry is sprayed from the feeding tank 10 to the surface of the coating roller 2 by the peristaltic pump at a flow rate of 15mL / min and transferred to the preheated copper foil. When the back roller 5 is subjected to transmission impact during equipment operation, the elastic damping component absorbs the 6-100Hz high frequency vibration (the measured amplitude drops from 20μm to ≤2μm) and eliminates coating ripples.

[0032] 4. When the detected coating thickness deviation is >2%: the laser displacement sensor 13 feeds back the signal → the PLC calculates the compensation amount → the servo motor 14 drives the lead screw 7 to lift ±5μm to restore the standard gap; safe shutdown: first cut off the power supply of the heating device 11, wait for the back roller 5 to cool down to below 40℃, and then stop the coating roller 2 from rotating to avoid the slurry from solidifying.

[0033] This utility model is a lithium battery electrode coating device that integrates four technologies: precision mechanical transmission, real-time sensing feedback, active temperature control, and damping vibration suppression. It breaks through industry bottlenecks and provides core equipment support for the mass production of ultra-thin, high-capacity lithium battery electrodes.

[0034] Finally, it should be noted that the above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A lithium battery electrode coating apparatus, characterized in that, include: A base (1) has coating rollers (2) that can rotate synchronously at both ends, and the two coating rollers (2) are linked by a transmission gear set; a drive motor (19) has its output shaft connected to the rotating shaft of any of the coating rollers (2) or the transmission gear set; a guide roller (3) is arranged parallel to the feed side of the coating roller (2); vertical fixing plates (4) are symmetrically fixed on both sides of the base (1); a back roller (5) is rotatably supported between the two vertical fixing plates (4) through a bearing seat (6); an adjustment mechanism includes a U-shaped guide groove opened on the inner side of the vertical fixing plate (4), and sliders (20) located on both sides of the bearing seat (6) and slidingly engaged with the U-shaped guide groove, with the bottom end fixed to the shaft. The adjusting screw (7) at the top of the support (6), the U-shaped fixed seat (8) at the top of the vertical fixed plate (4), the lifting drive device (9) at both ends of the U-shaped fixed seat (8), and the output end of the device are connected to the top of the adjusting screw (7) for transmission; the feeding trough (10) is built into the lower part of the base (1) and connected to the slurry nozzle above the coating roller (2) through the pump pipe; the heating device (11) is connected to the end of the back roller (5) through the rotary joint, and the heating wire (12) of the heating device (11) extends into the cavity inside the back roller (5); the high-precision laser displacement sensor (13) is symmetrically arranged on the opposite side of the two vertical fixed plates (4), and its optical axis points to the axial center point of the guide roller (3).

2. The lithium battery electrode coating apparatus according to claim 1, characterized in that, The lifting drive device (9) includes a servo motor (14) fixed to the outside of the U-shaped fixed base (8), and a bevel gearbox (15) with the input end connected to the output shaft of the servo motor (14) and the output end extending downward. The output end is connected to the top of the adjusting screw (7) through a coupling.

3. The lithium battery electrode coating apparatus according to claim 2, characterized in that, The bevel gearbox (15) contains a pair of orthogonally meshing bevel gears for converting horizontal rotational motion into vertical rotational motion.

4. The lithium battery electrode coating apparatus according to claim 1, characterized in that, The heating device (11) includes: a temperature sensor (17) located inside the back roller (5), an electrical control box (16) connected to the heating wire (12) via a conductive slip ring, and a temperature controller (18) that receives the signal from the temperature sensor (17) and controls the operation of the electrical control box (16).

5. The lithium battery electrode coating apparatus according to claim 1, characterized in that, The back roller (5) is arranged parallel to the coating roller (2), and an adjustable coating gap is formed between them; the displacement signal detected by the high-precision laser displacement sensor (13) is used to provide feedback and monitor the coating gap width of the guide roller (3) relative to the vertical fixed plate (4).

6. The lithium battery electrode coating apparatus according to claim 1, characterized in that, An elastic damping component is provided between the bearing seat (6) and the U-shaped guide groove. The elastic damping component is sleeved on the outside of the slider (20) and is used to provide buffering, shock absorption and positioning retention force when the bearing seat (6) slides.

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