Online spraying device and method applied to lithium ion battery diaphragm

Abstract

The invention discloses an online spraying device and method applied to a lithium ion battery diaphragm, and relates to the technical field of lithium ion battery diaphragms.The online spraying device comprises a conveying device, the outer side of the conveying device is wound with a diaphragm body, and the diaphragm body sequentially penetrates through the inner side of a spraying device and the inner side of a drying device to be connected with a winding device; and the outer side of the spraying device is connected with a liquid supply device. The problems that according to a conventional spraying device, a spraying head is used for conducting fixed-point spraying on a diaphragm, due to the fixed spraying distance and range and the spraying angle problem, the coating effect of the diaphragm is not optimal, and when the size of the diaphragm is enlarged, size adjustment is difficult are solved, meanwhile, independent equipment is adopted, and the cost is low. The problems that in the diaphragm treatment process, wrinkles are likely to be generated through multiple times of loading and unloading, so that diaphragms are polluted, parameters of all devices are independently adjusted, and the collaboration is poor are solved.

Description

Technical Field

[0001] This invention relates to the field of lithium-ion battery separator technology, and specifically to an online spraying device and method for lithium-ion battery separators. Background Technology

[0002] The separator of a lithium-ion battery is a key internal component of the battery. Its main function is to separate the positive and negative electrodes of the battery to prevent short circuits caused by contact between the two electrodes, while allowing lithium ions to pass freely during charging and discharging. The performance of the separator directly determines the battery's interface structure, internal resistance, capacity, cycle life, and safety performance. The separator needs to be surface coated before use.

[0003] Compared to existing spraying equipment, conventional spraying equipment has the following drawbacks: conventional spraying equipment uses a nozzle to spray the diaphragm at a fixed point. This method results in suboptimal coating of the diaphragm due to the fixed spraying distance and range, as well as the issue of the spraying angle. It is also difficult to adjust the size of the diaphragm when its size increases. In addition, the use of independent equipment leads to intermittent operation and requires manual transfer. During the diaphragm processing, repeated loading and unloading can easily cause wrinkles, leading to diaphragm contamination. Furthermore, the parameters of each piece of equipment are adjusted independently, resulting in poor coordination. Summary of the Invention

[0004] The purpose of this invention is to provide an online spraying device and method for lithium-ion battery separators, solving the following technical problems: Conventional spraying devices use nozzles to spray the separator at fixed points. This method results in suboptimal coating effects due to the fixed spraying distance and range, as well as the spraying angle. It is also difficult to adjust the size of the separator when its size increases. Furthermore, the use of independent equipment leads to intermittent operation and requires manual transfer. During the separator processing, repeated loading and unloading can easily cause wrinkles, leading to separator contamination. Additionally, the parameters of each device are adjusted independently, resulting in poor coordination.

[0005] The objective of this invention can be achieved through the following technical solutions: An online spraying device for lithium-ion battery separators includes: a conveying device, a separator body wound around the outside of the conveying device, the separator body passing through the inner sides of the spraying device and the drying device and connected to the winding device in sequence, and a liquid supply device connected to the outside of the spraying device. The spraying device has a first guide roller and a second guide roller respectively installed at the front of the interior to guide and transport the diaphragm body, and a rear housing that can move the spray head back and forth is installed at the rear of the spraying device. The rear end of the rear housing is provided with a movable baffle that moves back and forth, which is used to control and adjust the slurry. The inside of the spraying device is provided with movable plates on both the left and right sides, which are used to limit the diaphragm body on the side.

[0006] As a further embodiment of the present invention: a fixing plate connected to the nozzle is fixedly installed at the front of the rear housing, and a material conveying pipe connected by a first bolt is installed at equal distances between the fixing plate and the inner side of the rear housing. The rear upper side of the rear housing is provided with a top plate that is threadedly connected by a second bolt, and the front end of the top plate is provided with a first hydraulic telescopic rod that is connected to the spraying device.

[0007] As a further aspect of the present invention: a reciprocating lead screw connected to the rear housing is provided on the inner and outer sides of the movable baffle, a gear disk is fixedly installed on the outer end of the reciprocating lead screw, and an internal toothed belt is provided on the outer side of the gear disk; The movable baffles are arranged symmetrically about the center line of the rear housing.

[0008] As a further embodiment of the present invention: the front end of the rear housing is provided with holes and slots at equal intervals corresponding to the position of the feed pipe, and the rear housing is connected to the liquid supply device through a pipe; The fixing plate forms a snap-fit ​​sliding structure at the rear end of the spraying device through the rear groove, and the rear end surface of the spraying device is fitted to the left and right end surfaces of the rear housing.

[0009] As a further embodiment of the present invention: the movable baffle is threadedly connected to the reciprocating lead screw, and the gear disk is meshed with the internal gear belt; The front and rear outer surfaces of the movable baffle are both fitted to the inner wall of the rear housing, and the inner end of the movable baffle is inclined.

[0010] As a further embodiment of the present invention: the first guide roller is provided in two parts, one of which is wrapped and fitted with the diaphragm body, and the other part is flush with the rear surface of the first guide roller and the rear surface of the second guide roller. The rear surface of the second guide roller is fitted to the diaphragm body, which is penetrated through the first and second through grooves into the inner side of the spraying device.

[0011] As a further aspect of the present invention: a through hole is provided on the inner side of the movable plate, and a limiting bracket connected to the spraying device is provided on the inner side of the through hole. A first side baffle is provided on the inner side of the upper end of the movable plate, and a second side baffle is provided on the lower rear end of the movable plate. The inner end of the movable plate is provided with a side pulley.

[0012] As a further aspect of the present invention: the movable plate forms a nested sliding structure on the limiting bracket through the through hole; The first side baffle is fitted to the second through groove, and the second side baffle is fitted to the first through groove.

[0013] As a further embodiment of the present invention: the side pulley is rotatably connected to the movable plate, the inner end of the side pulley is provided with a rounded chamfer, and the inner surface of the side pulley is fitted to the left and right end surfaces of the diaphragm body.

[0014] As a further aspect of the present invention: a method for online spraying of lithium-ion battery separators, specifically comprising the following steps: S1: Unwinding and tension control: The high-precision motor and tension control system ensures smooth unwinding and maintains constant tension in the base film throughout the process, resulting in a smooth and wrinkle-free surface. S2: Guiding and conveying. The base film is guided along a predetermined path using guide rollers, and the conveying speed is precisely controlled by a variable frequency motor, providing a stable foundation for subsequent processes. S3: Online tight spraying, in a sealed spraying chamber, the adjustable column of atomizing spray guns performs automated spraying according to process parameters to ensure uniform coating; S4: Programmed drying. The wet film after spraying immediately enters a multi-section drying tunnel with independent temperature and air control, and undergoes efficient and uniform drying treatment according to a preset curve. S5: Winding and correction: Winding is performed under constant tension, and the edge detection device automatically corrects the deviation to ensure that the finished diaphragm roll is neat and tight; S6: Fully integrated control, with a central PLC system to centrally monitor and coordinate all units, achieving fully automated and intelligent production from unwinding to rewinding.

[0015] The beneficial effects of this invention are: 1. Production efficiency significantly improved Continuous automated operation: It realizes integrated continuous production from unwinding, spraying, drying to rewinding, eliminating the transfer, waiting and multiple loading and unloading time of materials between different independent equipment in traditional processes, and greatly shortening the production cycle; Highly stable operation: The sophisticated transmission and control system ensures that the equipment can operate stably at high speeds, meeting the stringent efficiency requirements of large-scale industrial production. 2. Excellent and stable product quality Eliminating physical damage: This avoids the transfer of the diaphragm between processes, fundamentally eliminating the risks of wrinkles, scratches, and contamination, and ensuring the integrity of the base membrane; Uniform and consistent coating: The precise spray gun array design, closed-loop controlled tension system, and real-time linkage between spraying parameters and linear speed ensure that the coating thickness has extremely high uniformity in both the longitudinal and transverse directions, thereby improving the mechanical properties and electrochemical consistency of the diaphragm. Excellent drying effect: The multi-segment programmable drying tunnel provides a uniform and gentle drying environment, preventing special layer defects and diaphragm deformation caused by uneven drying. 3. Production costs are effectively reduced. Reduced manpower and equipment input: Highly automated continuous production lines reduce reliance on operators and lower investment in multiple independent machines and their transfer areas; Minimize raw material waste: The sealed spray booth and precise control of the spraying system greatly reduce the splashing and evaporation of the spraying liquid, improve the utilization rate of raw materials, and directly reduce material costs; 4. Enhanced safety and environmental friendliness Operational safety: Automated production reduces human intervention, lowers the risk of operational errors, and reduces the probability of workers coming into contact with chemicals; Environmentally friendly: The closed-loop spraying and efficient recycling system reduces the emission of volatile organic compounds and the generation of waste liquid, making it more in line with environmental protection requirements. Attached Figure Description

[0016] The invention will now be further described with reference to the accompanying drawings.

[0017] Figure 1 This is a schematic diagram of the overall device structure of the present invention; Figure 2 This is a schematic diagram of the overall structure of the spraying device of the present invention; Figure 3 This is the invention Figure 2 Enlarged structural diagram at point A in the middle; Figure 4 This is a schematic cross-sectional view of the overall structure of the spraying device of the present invention; Figure 5 This is an exploded view of the overall structure of the connection between the rear housing and the fixing plate of the present invention; Figure 6 This is an exploded view of the overall structure of the connection between the rear housing and the top plate of the present invention; Figure 7 This is a schematic cross-sectional view of the connection between the spraying device and the cover plate of the present invention; Figure 8 This is an exploded view of the overall structure of the connection between the second guide roller and the diaphragm body of the present invention; Figure 9 This is an exploded view of the overall structure of the spraying device and the movable plate of the present invention. Figure 10 This is a schematic diagram of the operation steps of the present invention.

[0018] In the diagram: 1. Conveying device; 2. Spraying device; 201. Rear housing; 2011. Fixing plate; 2012. Spray head; 2013. Material conveying pipe; 2014. First bolt; 2015. Rear slot; 202. Top plate; 2021. Second bolt; 2022. First hydraulic telescopic rod; 203. First servo motor; 2031. Gear disk; 2032. Internal gear belt; 2033. Reciprocating lead screw; 2034. Movable baffle; 204. 205. First guide roller; 206. Second guide roller; 207. Diaphragm body; 208. First through groove; 209. Second through groove; 2007. Movable plate; 20071. Second hydraulic telescopic rod; 20072. Through hole; 20073. Limiting bracket; 20074. First side baffle; 20075. Second side baffle; 20076. Side pulley; 201. Cover plate; 20081. Third bolt; 202. Liquid supply device; 203. Drying device; 204. Winding device. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figure 1-10 As shown, the present invention is an online spraying device and method for lithium-ion battery separators.

[0021] Example 1 Please see Figure 1 In this invention, a technical solution is provided: a conveying device 1, a diaphragm body 206 is wound around the outside of the conveying device 1, the diaphragm body 206 passes through the inner side of the spraying device 2 and the drying device 4 in sequence and is connected to the winding device 5, and a liquid supply device 3 is connected to the outside of the spraying device 2. The front of the spraying device 2 is provided with a first guide roller 204 and a second guide roller 205 for guiding and conveying the diaphragm body 206. The rear side of the spraying device 2 is provided with a rear housing 201 that can move the spray head 2012 back and forth. The rear housing 201 has a movable baffle 2034 that moves back and forth on the inner side of the rear end, which is used to control and adjust the slurry. The spraying device 2 has movable plates 207 on both the left and right sides inside, which are used to limit the diaphragm body 206 on the side.

[0022] Specifically, the conveyor device 1 uses a YASKAWA Sigma-7 series servo motor (model S7100, 1.5KW, 1000r / min) as the unwinding power source. With its excellent low-frequency torque characteristics and overload capacity, this motor ensures extremely smooth unwinding start-up, acceleration, and stopping processes, avoiding tension impact from the source. Working in tandem with it is a BECKHOFF TX9000 series tension controller, which constructs a closed-loop control system: by acquiring the actual tension of the base film in real time through a high-response tension sensor and comparing it with the preset tension curve in the PLC, the output torque of the servo motor is dynamically adjusted using an adaptive PID algorithm, thereby accurately controlling the tension fluctuation of the base film during the entire unwinding process within ±0.5%, effectively suppressing wrinkling and stretching deformation of the base film.

[0023] The drying tunnel is physically divided into multiple independent drying sections (usually 3-5 sections). Each section forms an independent temperature and humidity control chamber, which can set an optimal drying temperature curve for the diaphragm based on the volatility characteristics of the slurry solvent. Each drying section is equipped with an independent control system: temperature control, which adopts an Omron E5AZ series high-precision PID temperature controller, and K-type thermocouples to monitor the chamber temperature in real time. The controller dynamically adjusts the power output of the infrared heating tube with an accuracy of ±0.5℃ according to the preset heating-holding-cooling curve to ensure uniform heat radiation. For wind speed and air volume control, Panasonic FV series centrifugal fans are used. The hot air speed delivered to each tunnel section is infinitely adjustable within the range of 2 to 10 m / s via a frequency converter. High wind speed is suitable for the strong drying stage where solvents evaporate rapidly, while low wind speed is used for gentle drying of the diaphragm to prevent the coating from being blown away. For humidity and exhaust control, each tunnel section is equipped with a dehumidification vent. By adjusting the opening of the exhaust valve, the concentration of solvent vapor in the tunnel is precisely controlled. This not only avoids insufficient drying due to excessive humidity in the early stage of drying, but also prevents excessive extraction of moisture from the diaphragm due to excessively dry air in the later stage of drying, which would affect its performance.

[0024] To achieve uniform drying, the heating device and air supply ducts are optimized through computational fluid dynamics simulation to ensure uniform temperature and air velocity distribution across the tunnel cross-section. The directional airflow generated by the ventilation system can promptly expel humid air rich in solvent vapors while simultaneously replenishing hot air for drying, significantly improving mass transfer efficiency. This enables highly efficient drying within a very short tunnel length. The entire drying system is integrated with the main PLC of the production line. The PLC automatically calculates the residence time of the base film in the tunnel based on its transfer speed and synchronously adjusts the temperature and humidity setpoints of each section to achieve dynamic process matching. The system also integrates multi-point over-temperature alarms and automatic fire extinguishing devices to ensure operational safety.

[0025] The core drive of the winding device uses the same YASKAWA Sigma-7 series servo motor as the unwinding device, ensuring that the speed can be reduced smoothly and accurately as the winding diameter increases. Working in conjunction with the drive system is the BECKHOFF TX9000 series tension controller, which constructs a tight closed-loop control system. The tension sensor detects the actual tension of the film surface in real time and feeds the signal back to the PLC. The PLC uses a tapered tension control algorithm to automatically reduce the tension set value linearly or curvilinearly as the roll diameter increases. This algorithm can effectively prevent the generation of winding defects such as "chrysanthemum core" or "star shape", ensuring that the diaphragm has uniform tightness from the inside to the outside and controlling the winding tension fluctuation within ±1%. Edge position control and automatic correction: To ensure that the edges of the diaphragm roll are neat and knife-cut, the system is equipped with a high-precision edge position control system. Its core component is the PZ series photoelectric sensor. This sensor can monitor the edge position of the diaphragm in real time with micron-level repeatability. When an edge deviation is detected, the signal is immediately transmitted to the PLC. The PLC then drives a high-response servo slide or a set of precision linear modules to make the entire winding device move slightly and precisely in the lateral direction (correction accuracy can reach ±0.5mm), thereby dynamically aligning the edge of the diaphragm to a fixed reference line at all times. For ultra-thin and easily wrinkled diaphragms, the winding device also employs center / surface winding switching or pressure roller contact control technology. A pressure roller with a specially coated surface contacts the surface of the master roll with adjustable pressure, suppressing air entrapment and smoothing micro-wrinkles through physical force. The pressure of this pressure roller can be programmed and controlled according to process requirements. Higher pressure is used in the initial winding stage to build a solid core, and the pressure is gradually reduced in subsequent stages to optimize the roll shape and reduce the compressive stress on the inner diaphragm.

[0026] Example 2 This embodiment is derived based on Embodiment 1. Please refer to [link / reference]. Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6 In this invention, a technical solution is provided: a fixing plate 2011 connected to a nozzle 2012 is fixedly installed at the front of the rear housing 201, and a feed pipe 2013 connected by a first bolt 2014 is installed at equal intervals on the fixing plate 2011 and the inner side of the rear housing 201. The rear housing 201 has a top plate 202 threadedly connected to the upper rear end by a second bolt 2021. The front end of the top plate 202 has a first hydraulic telescopic rod 2022 connected to the spraying device 2.

[0027] Furthermore, a reciprocating screw 2033 connected to the rear housing 201 is provided on the inner and outer sides of the movable baffle 2034. A gear disk 2031 is fixedly installed on the outer end of the reciprocating screw 2033, and an internal toothed belt 2032 is provided on the outer side of the gear disk 2031. The movable baffle 2034 is symmetrically arranged about the center line of the rear housing 201.

[0028] Furthermore, the front end of the rear housing 201 is provided with holes and slots at equal intervals corresponding to the positions of the feed pipe 2013, and the rear housing 201 is connected to the liquid supply device 3 through a pipe. The fixing plate 2011 forms a snap-fit ​​sliding structure at the rear end of the spraying device 2 through the rear slot 2015, and the rear end surface of the spraying device 2 is attached to the left and right end surfaces of the rear housing 201.

[0029] Furthermore, the movable baffle 2034 is threadedly connected to the reciprocating lead screw 2033, and the gear disk 2031 is meshed with the internal gear belt 2032; The front and rear outer surfaces of the movable baffle 2034 are both fitted to the inner wall of the rear housing 201, and the inner end of the movable baffle 2034 is inclined.

[0030] Furthermore, there are two first guide rollers 204, one of which is wrapped and attached to the diaphragm body 206, and the other first guide roller 204 is flush with the rear surface of the second guide roller 205. The rear surface of the second guide roller 205 is attached to the diaphragm body 206, and the diaphragm body 206 passes through the inner side of the spraying device 2 through the first through groove 2061 and the second through groove 2062 respectively.

[0031] Specifically, in embodiment one, after the diaphragm body 206 passes through the first through groove 2061 to the lower rear end of the spraying device 2, it wraps and adheres to the first guide roller 204, and then passes through the second through groove 2062 to the upper end of the spraying device 2. Afterwards, the cover plate 208 is threadedly connected to the spraying device 2 using the third bolt 2081. This ensures a relatively sealed state inside the spraying device 2. When the winding device 5 winds up the diaphragm body 206, the diaphragm body 206 can be... 06 generates driving force. At this time, opening the first hydraulic telescopic rod 2022 can drive the fixing plate 2011 fixedly installed at the front end of the rear housing 201 to move in a snap-fit ​​manner at the rear end of the spraying device 2 through the rear slot 2015, so that the front end surface of the nozzle 2012 can approach the rear surface of the diaphragm body 206 according to the spraying needs. At this time, the slurry is transported into the rear housing 201 through the liquid supply device 3. Under the action of pressure, the slurry can be sprayed from the nozzle 2012 to the diaphragm body 206 for coating.

[0032] Furthermore, when spraying the diaphragm body 206, the spraying range of the nozzle 2012 can be adjusted according to the left and right lateral dimensions of the diaphragm body 206. Since the nozzles 2012 are arrayed at the front end of the fixing plate 2011, and a feed pipe 2013 installed between the rear housing 201 and the fixing plate 2011 is provided on the rear side of the nozzles 2012, the slurry can be evenly transported from the rear housing 201 to the nozzles 2012 along the feed pipe 2013. The feed pipe 2013 is threadedly connected to the rear housing 201 and the fixing plate 2011 respectively by the first bolt 2014, which allows the feed pipe 2013 to be disassembled independently in the future, avoiding the effect of blockage and difficulty in cleaning caused by long-term use.

[0033] The rear housing 201 has a movable baffle 2034 on its inner side. When the first servo motor 203 is turned on to rotate the gear disk 2031, the gear disk 2031 and its corresponding unit can be driven to rotate synchronously and in the same direction through the internal toothed belt 2032 meshing with the outer side of the gear disk 2031. Thus, the rotation of the gear disk 2031 drives the reciprocating screw 2033 to rotate synchronously. Since the reciprocating screw 2033 is threadedly connected to the movable baffle 2034, it can be adjusted according to the actual machining of the diaphragm body 206. The width determines the slurry output range. The front and rear ends of the movable baffle 2034 are both fitted against the inner wall of the rear housing 201, and the inner end of the movable baffle 2034 is inclined. When the movable baffle 2034 moves back and forth in opposite directions inside the rear housing 201, it can block the slot at the connection between the rear end of the conveying pipe 2013 and the rear housing 201, thereby controlling the slurry output. This allows for control of the spray coating range based on the actual width of the diaphragm body 206, achieving a better spray coating effect.

[0034] The precision transmission and guiding system features a base film driven by a LENZE 8400 series variable frequency speed control motor (2.2KW). This motor has a wide speed range (10-1000r / min) and extremely high speed stability (±0.5%), ensuring that the base film passes through the spraying area at a constant speed. Multiple sets of SKF R85 series aluminum guide rollers (specifications: φ50mm×300mm) are installed along the transmission path. These rollers undergo hard anodizing and high-precision dynamic balancing, resulting in extremely high surface smoothness. Combined with low-resistance bearings, they effectively reduce base film deviation and friction damage, providing a stable material base for precision spraying. Closed-loop spraying and supply system: The spraying process takes place in a sealed stainless steel spraying chamber with a negative pressure design, effectively preventing solvent evaporation and paint splashing, complying with environmental protection and safety production standards. The core spray gun array inside the chamber adopts SATA... The Jet5000 series high-precision atomizing spray guns offer flexible options for nozzle diameter (0.5–1.5 mm) and spray flow rate (50–500 ml / min) to suit various process requirements. The spray gun layout features a programmable modular design, allowing for rapid adaptation to diaphragm widths (e.g., 500 mm to 1500 mm) to ensure uniform coating coverage. The spraying liquid is stored in a 316L stainless steel tank (500L capacity) and supplied with stable pressure via a GRUNDFOS CR series magnetically driven delivery pump (flow rate 5–20 L / min, head 30–50 m). Before reaching the spray gun, the slurry passes through one or more high-precision filters (filtration accuracy 5–10 μm) to thoroughly remove any agglomerated particles, preventing spray gun clogging or diaphragm surface defects caused by impurities. Intelligent control and closed-loop regulation system: The "brain" of the entire production line is the Siemens S7-1500 series high-performance PLC. By integrating multiple sensors to form a closed-loop feedback, the PLC compares the collected real-time data with the preset process formula and dynamically adjusts the transmission speed, spray volume and atomization effect. The transmission speed is precisely controlled by the LENZE driver to ensure stable linear speed. The spray volume is adjusted by the proportional valve to regulate the on / off sequence and flow of the SATA spray gun to achieve quantitative spraying. The atomization effect is independently controlled by the compressed air pressure to ensure uniform and delicate droplet atomization.

[0035] Example 3 This embodiment is derived based on Embodiment 1 and Embodiment 2. Please refer to [link / reference]. Figure 2 , Figure 4 , Figure 7 , Figure 8 and Figure 9 In this invention, a technical solution is provided: a through hole 2072 is provided on the inner side of the movable plate 207, and a limiting bracket 2073 connected to the spraying device 2 is provided on the inner side of the through hole 2072. A first side baffle 2074 is provided on the inner side of the upper end of the movable plate 207, and a second side baffle 2075 is provided on the lower rear end of the movable plate 207. The inner end of the movable plate 207 is provided with a side pulley 2076.

[0036] Furthermore, the movable plate 207 forms a nested sliding structure on the limiting bracket 2073 through the through hole 2072; The first side baffle 2074 is fitted to the second through groove 2062, and the second side baffle 2075 is fitted to the first through groove 2061.

[0037] Furthermore, the side pulley 2076 is rotatably connected to the movable plate 207, the inner end of the side pulley 2076 is provided with a rounded chamfer, and the inner surface of the side pulley 2076 is fitted to the left and right end surfaces of the diaphragm body 206.

[0038] Specifically, in conjunction with Embodiments 1 and 2, the actual width of the diaphragm body 206 has been confirmed before spraying. At this time, the second hydraulic telescopic rod 2071 is opened to drive the movable plate 207 to move left and right in opposite directions within the spraying device 2. This allows the movable plate 207 to slide stably in a nested manner on the limiting bracket 2073 through the through hole 2072. This not only avoids the rotational conveying of the first guide roller 204 and the second guide roller 205, but also limits the lateral movement of the movable plate 207, preventing misalignment during its movement. At the same time, the first side baffle 2074 set at the upper end of the movable plate 207 will block the second through groove 2062 according to the actual width of the diaphragm body 206, and the second side baffle 2075 set at the lower rear end of the movable plate 207 will block the first through groove 2061. This operation serves two purposes: first, to seal the spraying device 2 and prevent gas or impurities from entering; and second, to limit the inlet and outlet of the diaphragm body 206.

[0039] The movable plate 207 is provided with a side pulley 2076 at its inner end. The side pulley 2076 is provided with a rounded chamfer. When the movable plate 207 is moved inward, the inner surface of the side pulley 2076 can be made to fit with the left and right end surfaces of the diaphragm body 206, thereby centering and limiting the diaphragm body 206 to improve the uniformity of spray coating.

[0040] Example 4 Please refer to the figures and diagrams. This invention provides a technical solution: an online spraying method for lithium-ion battery separators, specifically including the following steps: Step 1: Diaphragm unwinding and tension initialization 1. Feeding and threading: The roll of uncoated lithium-ion battery separator base film is installed onto the roll of the unwinding device, and the front end of the base film is manually pulled through the preset path and around the tension detection roller. 2. Tension control start-up: Start the high-precision motor of the unwinding device (such as YASKAWA Sigma-7 series), and the built-in tension control system (such as BECKHOFF TX9000 series) starts working, providing real-time feedback on the tension value of the base film through the tension sensor; 3. Automatic adjustment: The control system compares the measured tension with the preset optimal process tension value, and automatically stabilizes the tension of the base film within the set range by adjusting the torque output of the motor, ensuring that the base film is released smoothly in a flat and vibration-free state.

[0041] Step 2: Base Film Guidance and Precise Transport 1. Path guidance: During operation, the base film passes through a series of guide rollers (such as smooth aluminum rollers). These rollers ensure that the base film always moves along a precise and predetermined path, preventing deviation. 2. Speed ​​setting and synchronization: The variable frequency speed control motor of the transmission drive device (such as the LENZE 8400 series) precisely controls the linear speed of the main production line (e.g., 50 meters / minute) according to the preset process parameters. This speed signal will be synchronized to the subsequent spraying and drying systems to ensure that the speed of the entire line is matched and to avoid stretching or accumulation caused by speed difference. Step 3: Online precision spraying 1. Spraying preparation Spraying liquid supply: When the liquid supply system is started, the spraying liquid is drawn from the storage tank by the delivery pump (such as GRUNDFOS CR series), and after impurities are removed by the filter (accuracy 5-1-μm), it is delivered to the spray gun array in the spraying chamber through the pipeline; Environmental sealing: The spray booth is kept sealed to prevent spray liquid droplets from splashing and solvent evaporation, ensuring a safe working environment and reducing material waste; 2. Start spraying: When the base film passes through the transfer roller below the spraying chamber, the control system (such as Siemens S7-1500 PLC) issues a command to start the spray gun (such as SATA Jet5000 series) according to the actual position and speed signal of the base film; the spray gun atomizes the spraying liquid with high precision to form uniform micro-droplets; 3. Dynamic control and adjustment Spray gun linkage: The on / off state, spray volume, and spray angle of the spray gun may be linked to the speed of the base film. For example, when the production line accelerates, the system will automatically increase the spray volume proportionally to ensure a constant coating thickness. Uniformity Guarantee: Multiple spray guns are arranged in an array, and their number, spacing, and angle can be flexibly adjusted according to the width of the diaphragm and the coating requirements to ensure the uniformity of the coating in the width direction of the diaphragm. Step 4: Multi-stage controlled drying 1. Entering the drying tunnel: The wet film after spraying immediately enters the multi-stage drying tunnel along with the base film without any pause or transfer in between; 2. Segmented drying: The drying tunnel is divided into multiple independent temperature zones (such as the preheating zone, the main drying zone, and the shaping zone). Preheating zone: A lower temperature (e.g., 60°C) is used to initially set the coating surface and prevent droplets from flowing. Main drying zone: A higher temperature (e.g., 80-100℃) is used to rapidly evaporate most of the solvent in the coating through infrared heating tubes and hot air circulation; Shaping zone: The temperature is slightly lower than that of the main drying zone (e.g., 70°C), allowing the diaphragm to cool slowly, releasing internal stress, and preventing deformation due to rapid shrinkage; 3. Environmental control: The temperature control system (such as Omron E5AZ series thermostat) and ventilation system (such as Panasonic FV series fan) of each tunnel section work independently, monitor and adjust the temperature, wind speed and humidity in real time, and remove moisture in time to ensure uniform and efficient drying effect; Step 5: Finished product winding and automatic deviation correction 1. Tension and speed matching: After drying, the finished diaphragm enters the winding system. The high-precision motor of the winding device keeps the speed synchronized with the unwinding and transmission system. Its tension control system ensures that the winding tension is constant, so that the roll is tight and neat. 2. Edge correction: During the winding process, the edge detection device (such as the KEYENCE PZ series photoelectric sensor) continuously monitors the position of the diaphragm edge. Once an edge deviation is detected (within ±1mm), it will immediately send a signal to the control system. The control system will automatically fine-tune the lateral position of the winding shaft to pull the diaphragm back to the correct path and ensure that the winding edge is neat. Step Six: Full-line automated control and monitoring All the above steps are integrated and controlled by the central PLC control system. The operator only needs to set the process parameters (such as linear speed, tension value, spraying volume, drying temperature curve, etc.) on the human-machine interface (HMI), and the system can automatically complete the entire production process and display the equipment status and alarm information in real time, realizing intelligent production.

[0042] The foregoing has provided a detailed description of one embodiment of the present invention, but this description is merely a preferred embodiment and should not be construed as limiting the scope of the invention. All equivalent variations and modifications made within the scope of the claims of this invention should still fall within the patent coverage of this invention.

Claims

1. An online spraying device for lithium-ion battery separators, characterized in that, The device includes a conveying device (1), on the outside of which a diaphragm body (206) is wound, and the diaphragm body (206) passes through the inside of the spraying device (2) and the drying device (4) and is connected to the winding device (5). The outside of the spraying device (2) is connected to a liquid supply device (3). The spraying device (2) is provided with a first guide roller (204) and a second guide roller (205) for guiding and conveying the diaphragm body (206) at the front of the interior, and a rear housing (201) for reciprocating movement of the spray nozzle (2012) is provided at the rear of the spraying device (2). The rear housing (201) is provided with a movable baffle (2034) that moves back and forth on the inner side of the rear end, which is used to control and adjust the slurry. The spraying device (2) is provided with movable plates (207) on both the left and right sides inside, which are used to limit the diaphragm body (206) on the side.

2. The online spraying device for lithium-ion battery separators according to claim 1, characterized in that, A fixing plate (2011) connected to the nozzle (2012) is fixedly installed at the front of the rear housing (201). A feed pipe (2013) connected by a first bolt (2014) is installed at equal intervals on the inner side of the fixing plate (2011) and the rear housing (201). The rear housing (201) has a top plate (202) threadedly connected by a second bolt (2021) on the upper rear side. The top plate (202) has a first hydraulic telescopic rod (2022) connected to the spraying device (2) at the front end.

3. The online spraying device for lithium-ion battery separators according to claim 2, characterized in that, The movable baffle (2034) is provided with a reciprocating screw (2033) connected to the rear housing (201) on the inner and outer sides. A gear disk (2031) is fixedly installed on the outer end of the reciprocating screw (2033), and an internal toothed belt (2032) is provided on the outer side of the gear disk (2031). The movable baffle (2034) is symmetrically arranged about the center line of the rear housing (201).

4. The online spraying device for lithium-ion battery separators according to claim 2, characterized in that, The front end of the rear housing (201) is provided with holes and slots at equal intervals corresponding to the position of the feed pipe (2013), and the rear housing (201) is connected to the liquid supply device (3) through a pipe; The fixing plate (2011) forms a snap-fit ​​sliding structure at the rear end of the spraying device (2) through the rear slot (2015), and the rear end surface of the spraying device (2) is fitted to the left and right end surfaces of the rear housing (201).

5. The online spraying device for lithium-ion battery separators according to claim 3, characterized in that, The movable baffle (2034) is threadedly connected to the reciprocating lead screw (2033), and the gear disk (2031) is meshed with the internal gear belt (2032); The front and rear outer surfaces of the movable baffle (2034) are both fitted to the inner wall of the rear housing (201), and the inner end of the movable baffle (2034) is inclined.

6. The online spraying device for lithium-ion battery separators according to claim 1, characterized in that, The first guide roller (204) is configured as two, one of which is wrapped and attached to the diaphragm body (206), and the other is flush with the rear surface of the first guide roller (204) and the rear surface of the second guide roller (205); The rear surface of the second guide roller (205) is attached to the diaphragm body (206), and the diaphragm body (206) passes through the inner side of the spraying device (2) through the first through groove (2061) and the second through groove (2062).

7. The online spraying device for lithium-ion battery separators according to claim 1, characterized in that, The inner side of the movable plate (207) is provided with a through hole (2072), and the inner side of the through hole (2072) is provided with a limiting bracket (2073) connected to the spraying device (2). A first side baffle (2074) is provided on the inner side of the upper end of the movable plate (207), and a second side baffle (2075) is provided on the lower rear end of the movable plate (207). The inner end of the movable plate (207) is provided with a side pulley (2076).

8. The online spraying device for lithium-ion battery separators according to claim 7, characterized in that, The movable plate (207) forms a nested sliding structure on the limiting bracket (2073) through the through hole (2072); The first side baffle (2074) is fitted to the second through groove (2062), and the second side baffle (2075) is fitted to the first through groove (2061).

9. The online spraying device for lithium-ion battery separators according to claim 7, characterized in that, The side pulley (2076) is rotatably connected to the movable plate (207). The inner end of the side pulley (2076) is provided with a rounded chamfer. The inner surface of the side pulley (2076) is attached to the left and right end surfaces of the diaphragm body (206).

10. A method for online spraying of a lithium-ion battery separator, characterized in that, The online spraying device for lithium-ion battery separators according to any one of claims 1-9 specifically includes the following steps: S1: Unwinding and tension control: The high-precision motor and tension control system ensures smooth unwinding and maintains constant tension in the base film throughout the process, resulting in a smooth and wrinkle-free surface. S2: Guiding and conveying. The base film is guided along a predetermined path using guide rollers, and the conveying speed is precisely controlled by a variable frequency motor, providing a stable foundation for subsequent processes. S3: Online tight spraying, in a sealed spraying chamber, the adjustable column of atomizing spray guns performs automated spraying according to process parameters to ensure uniform coating; S4: Programmed drying. The wet film after spraying immediately enters a multi-section drying tunnel with independent temperature and air control, and undergoes efficient and uniform drying treatment according to a preset curve. S5: Winding and correction: Winding is performed under constant tension, and the edge detection device automatically corrects the deviation to ensure that the finished diaphragm roll is neat and tight; S6: Fully integrated control, with a central PLC system to centrally monitor and coordinate all units, achieving fully automated and intelligent production from unwinding to rewinding.

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