Battery pole piece vacuum drying oven

Abstract

The utility model relates to lithium battery manufacturing equipment technical field discloses a battery pole piece vacuum drying oven, include: box, inside setting drying chamber, the box has gas import and gas export, gas import with gas export is connected with drying chamber respectively, the drying chamber is communicated with, take and put up the device, have at least two, interval setting in drying chamber, a plurality of guide rollers are arranged between two take and put up the device, circulating fan has the air inlet and the air outlet, the air inlet with the air outlet is connected with drying chamber respectively, the air outlet has a plurality of, a plurality of air outlet is in drying chamber towards the same circumferential direction setting, the deflector is set in drying chamber, the deflector has the arc shape guiding surface towards the air outlet, the utility model technical scheme, can guide the gas in drying chamber to form annular airflow, makes the gas more evenly flows in drying chamber, covers each part of battery pole piece.

Description

Technical Field

[0001] This utility model relates to the field of lithium battery manufacturing equipment technology, specifically to a vacuum drying oven for battery electrodes. Background Technology

[0002] The lithium battery electrode roll-to-roll vacuum drying oven is a key piece of equipment used for drying electrodes in the lithium battery production process. Its core function is to achieve low-temperature rapid evaporation and removal of moisture / solvent inside the electrode by continuously conveying the electrode in a vacuum environment and applying a controllable heat source, while avoiding electrode oxidation or material damage.

[0003] The working logic of a roll-to-roll vacuum drying oven for lithium battery electrodes is simple. The core principle is to continuously pass the electrodes through a heating zone in a vacuum environment to remove moisture. The specific steps include: First, the air in the drying chamber is evacuated, creating a near-vacuum state. This lowers the boiling point of water, allowing moisture to evaporate at a lower temperature (e.g., 60-120℃), preventing damage to the electrode material. Simultaneously, the absence of oxygen in a vacuum also prevents electrode oxidation. Then, through an unwinding mechanism, guide rollers, drying channel, and rewinding mechanism, the electrodes are continuously and uniformly conveyed within the equipment to ensure sufficient contact time with the heat source, achieving complete moisture evaporation.

[0004] There are three common types of heating devices installed inside drying ovens: Hot air heating: A small amount of inert gas (such as nitrogen) is introduced into a vacuum environment. The heated gas flows over the surface of the electrode and carries away the evaporated moisture.

[0005] Infrared heating: Infrared lamps emit infrared rays, and the electrode absorbs the infrared energy, raising the internal temperature and achieving uniform evaporation of moisture from the inside out, resulting in high drying efficiency.

[0006] Microwave heating: Microwaves penetrate the electrode sheet, causing water molecules inside the electrode sheet to vibrate at high frequency and generate heat. This can also achieve rapid and uniform drying, and is especially suitable for thick electrode sheets.

[0007] Chinese patent document CN205050922U discloses a rapid drying chamber for battery electrodes. A nitrogen pipeline is connected to the chamber body, and the nitrogen pipeline directly enters the inner cavity of the chamber. Its core function is to isolate oxygen inside the chamber (to prevent the positive electrode from oxidizing and deteriorating), while also helping to remove the moisture and NMP vapor evaporated from the electrode rolls. Combined with the vacuum pipeline, it achieves efficient drying.

[0008] However, in the above scheme, there is a problem of uneven diffusion of nitrogen within the chamber. Specifically, when nitrogen diffuses naturally from the inlet point to the surrounding areas, the nitrogen concentration is affected by distance attenuation. The nitrogen concentration is too high in areas near the nitrogen inlet (such as one side of the chamber), while the nitrogen concentration is insufficient in areas far from the inlet (such as the end of the feeding expansion shaft or the corner of the chamber), forming a "concentration gradient difference".

[0009] On the other hand, if the critical areas of electrode drying (such as the electrode intersection between the upper and lower drive shafts) are not covered by nitrogen pipes, oxygen may remain, making it impossible to effectively prevent oxidation and affecting the efficiency of steam removal. Utility Model Content

[0010] In view of this, the present invention provides a vacuum drying oven for battery electrodes to solve the problem of uneven nitrogen distribution in existing rapid drying ovens for battery electrodes.

[0011] This utility model provides a vacuum drying oven for battery electrodes, comprising: The chamber has a drying cavity inside, and the chamber has a gas inlet and a gas outlet, which are respectively connected to the drying cavity. The winding and unwinding device has at least two, which are spaced apart in the drying chamber, and a plurality of guide rollers are provided between the two winding and unwinding devices; A circulating fan has an air inlet and an air outlet, the air inlet and the air outlet are respectively connected to the drying chamber, and there are multiple air outlets, which are arranged in the same circumferential direction within the drying chamber; A baffle plate is disposed inside the drying chamber, and the baffle plate has an arc-shaped guide surface facing the air outlet.

[0012] This invention utilizes multiple air outlets of a circulating fan, arranged in the same circumferential direction within the drying chamber. Combined with the arc-shaped guide surface of the baffle plate, this guides the gas within the drying chamber to form a ring-shaped airflow. This ring-shaped airflow ensures more uniform gas distribution within the drying chamber, covering all parts of the battery electrode. The ring-shaped airflow reduces dead zones, ensuring that every part of the electrode is fully in contact with the hot gas, thereby improving drying uniformity. When drying large battery electrodes, it avoids the problem of uneven airflow leading to localized over- or under-drying, ensuring the overall consistency of the electrode quality.

[0013] Optionally, a slit air outlet structure is provided at the air outlet in the drying chamber.

[0014] In the above scheme, by setting up a slit air outlet structure, the flow rate of the inert gas at the air outlet is increased during the filling of inert gas.

[0015] Optionally, the plurality of guide rollers are adapted to support the battery electrodes in a multi-layer configuration that is sequentially connected and spaced apart.

[0016] In the above scheme, the guide roller can fully unfold the electrode sheet, which facilitates the evaporation of moisture.

[0017] Optionally, the system further includes: multiple air supply ducts, respectively disposed between the multiple layers of battery electrodes, wherein the air supply ducts are connected to the air inlet or air outlet of the circulating fan. Specifically, when the air supply duct is connected to the air inlet of the circulating fan, the circulating fan can transport gas from the drying chamber into the air supply duct, thereby disrupting the airflow between the multiple layers of battery electrodes; when the air supply duct is connected to the air outlet of the circulating fan, the circulating fan can transport gas into the drying chamber through the air supply duct, thereby disrupting the airflow between the multiple layers of battery electrodes.

[0018] In the above solution, by setting up the air supply duct, whether air is introduced or vented through the air supply duct, the airflow between the battery electrodes can be disturbed, thereby improving the drying efficiency between the multi-layer battery electrodes.

[0019] Optionally, the air supply duct has multiple vents in its circumference.

[0020] In the above solution, the drying process can be accelerated by setting up multiple ventilation openings, and localized accumulation of water vapor can be avoided.

[0021] Optionally, a correction system is provided on both sides of the battery electrode. The correction system includes a correction sensor and a correction roller, with the correction sensor and the correction roller arranged opposite to each other.

[0022] In the above scheme, the correction sensor controls the correction roller to correct the deviation in real time during the winding and unwinding process, so as to ensure the consistency of winding and unwinding and avoid deviation.

[0023] Optionally, the housing is provided with an insulation layer and a heating layer inside, with the insulation layer on the outside of the heating layer.

[0024] In the above solution, the internal heating and insulation of the box allows the battery electrodes to dry quickly and fully evaporate moisture.

[0025] Optionally, a moisture detection system is installed below the gas outlet.

[0026] In the above scheme, the drying process is automatically terminated by a real-time moisture detection system.

[0027] Optionally, an operating cavity is provided inside the housing.

[0028] In the above scheme, the operating cavity is used to place the various components, so that all the components are set inside the box.

[0029] Optionally, a microwave generator and a circulating fan are provided inside the operating cavity.

[0030] In the above scheme, the microwave generator further excites water molecules to resonate, accelerates diffusion, and greatly improves drying efficiency, thus playing an auxiliary role in drying. Attached Figure Description

[0031] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0032] Figure 1 This is a perspective view of a vacuum drying oven for battery electrodes according to an embodiment of the present invention. Figure 2 This is a perspective view of a vacuum drying oven for battery electrodes according to an embodiment of the present invention. Figure 3 This is a front view of a vacuum drying oven for battery electrodes according to an embodiment of the present invention; Figure 4 This is a perspective view of an air supply duct according to an embodiment of the present utility model.

[0033] Explanation of reference numerals in the attached figures: 1. Housing; 2. Insulation layer; 3. Heating layer; 4. Guide roller; 5. Winding and unwinding device; 6. Battery electrode; 7. Gas inlet; 8. Gas outlet; 9. Moisture detection system; 10. Microwave generator; 11. Circulating fan; 12. Correction sensor; 13. Correction roller; 14. Drying chamber; 15. Guide plate; 16. Slit air outlet structure; 17. Air supply duct; 18. Ventilation port; 19. Operating chamber. Detailed Implementation

[0034] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0035] like Figure 1 As shown, this is a specific implementation of the battery electrode vacuum drying oven provided in this embodiment, which includes: a box body 1, a winding and unwinding device 5, a circulating fan 11, and a guide plate 15.

[0036] like Figure 1 As shown, a drying chamber 14 is provided inside the box body 1. The box body 1 has a gas inlet 7 and a gas outlet 8, which are respectively connected to the drying chamber 14. like Figure 1As shown, two take-up and unwinding devices 5 are spaced apart in the drying chamber 14, and multiple guide rollers 4 are provided between the two take-up and unwinding devices 5. like Figure 2 As shown, the circulating fan 11 has an air inlet and an air outlet, which are respectively connected to the drying chamber 14. There are multiple air outlets, which are arranged in the same circumferential direction within the drying chamber 14. like Figure 1 , Figure 3 As shown, the guide plate 15 is disposed in the drying chamber 14, and the guide plate 15 has an arc-shaped guide surface facing the air outlet.

[0037] In this embodiment, the battery electrode 6 is passed through the guide roller 4, and both ends are wound onto the unwinding and winding device 5. The unwinding and winding device 5 simultaneously unwinds and winds, automatically switching to reverse rotation after forward rotation ends. During the baking process, vacuuming and nitrogen filling alternately create a pulse effect. The vacuum circulation pulse can break the capillary water adsorption force of the electrode, and under the action of the circulating fan 11 and the guide plate 15, the nitrogen inside the chamber 1 can flow regularly. Using this equipment, the nitrogen filling the drying oven is more evenly distributed, ensuring that every part of the battery electrode 6 is fully dried.

[0038] like Figure 2 , Figure 3 As shown, a slit air outlet structure 16 is provided at the air outlet in the drying chamber 14. This arrangement allows for directional flow of gas within the entire drying oven during nitrogen filling, further improving the drying effect.

[0039] Of course, the above description is not limiting. In some alternative embodiments, the slit air outlet structure 16 can be replaced with an exhaust vent.

[0040] like Figure 1 As shown, the plurality of guide rollers 4 are adapted to support the battery electrode sheets 6 in a multi-layered manner that is connected sequentially and spaced apart. This arrangement allows the guide rollers 4 to fully expand the electrode sheets, facilitating moisture evaporation.

[0041] Of course, the above description is not limiting; in some alternative embodiments, only one guide roller 4 may be provided.

[0042] like Figure 1 , Figure 2As shown, the system also includes multiple air supply ducts 17, respectively disposed between the multiple layers of battery electrode sheets 6. Each air supply duct 17 is connected to the air inlet or outlet of the circulating fan 11. When the air supply duct 17 is connected to the air inlet of the circulating fan 11, air from the drying chamber 14 enters the air supply duct 17; or when the air supply duct 17 is connected to the air outlet of the circulating fan 11, air enters the drying chamber 14 through the air supply duct 17. This configuration allows the air supply ducts 17 to agitate the airflow between the battery electrode sheets 6 through air inlet and outlet, thereby improving the drying efficiency between the multiple layers of battery electrode sheets 6.

[0043] In some embodiments, the air supply ducts 17 are rotatably disposed within the drying chamber 14, and each air supply duct 17 is connected to a rotary drive device, thereby allowing the air supply duct 17 to rotate along its axis within the drying chamber 14. This arrangement can create vortices in the airflow around the air supply duct 17, thereby improving the disturbance effect on the airflow around the air supply duct 17. Of course, the above description is not limiting; in some alternative embodiments, the air supply duct 17 may not rotate.

[0044] like Figure 4 As shown, the air supply duct 17 has multiple vents 18 around its circumference. This arrangement allows dry inert gas to be blown into the chamber through the vents 18. During the air supply process, the gas rotates to form an airflow vortex, accelerating the drying process and preventing localized moisture accumulation.

[0045] Of course, the above description is not limiting; in some alternative embodiments, the vent 18 may be provided as a single unit.

[0046] like Figure 2 , Figure 3 As shown, a correction system is installed on both sides of the battery electrode 6. The correction system includes a correction sensor 12 and a correction roller 13, which are arranged opposite to each other. The core working principle of the correction roller 13 is that the correction sensor 12 detects the material deviation position, and the controller drives the actuator to adjust the angle or position of the correction roller 13, guiding the material back to the correct conveying path, forming a closed-loop correction. Specifically, the laser correction sensor 12 monitors the positional change of the edge of the battery electrode 6, transmits the deviation signal to the controller, and the controller, through a servo motor, drives the correction roller 13 to rotate by a specific angle (or translate), changing the force direction on the battery electrode 6 and gradually pulling it back to the correct path. With this setup, the correction sensor 12 controls the correction roller 13 to monitor the winding and unwinding process in real time, ensuring consistency in winding and unwinding and preventing deviation.

[0047] Of course, the above description is not limiting, and in some alternative implementations, the correction system may be omitted.

[0048] like Figure 1As shown, the housing 1 has an insulation layer 2 and a heating layer 3 inside, with the insulation layer 2 located outside the heating layer 3. Specifically, the core function of the insulation layer 2 is to reduce heat loss, and it needs to directly wrap the heat source or the equipment body; the heating layer 3 is the core component that provides heat. With this arrangement, the housing 1 is heated and kept warm, allowing the battery electrode 6 to dry quickly and fully evaporate moisture.

[0049] Of course, the above description is not limiting. In some alternative embodiments, the heating layer 3 can be replaced with a semiconductor heating element.

[0050] like Figure 2 , Figure 3 As shown, a moisture detection system 9 is installed below the gas outlet 8. Specifically, when the gas is discharged from the chamber 1, the moisture content in the gas is tested by a dew point meter. With this setup, the drying process automatically ends if the moisture content meets the standard through the real-time moisture detection system.

[0051] Of course, the above description is not limiting. In some alternative embodiments, the moisture detection system 9 may be positioned above the gas outlet 8.

[0052] like Figure 2 As shown, an operating cavity 19 is provided inside the housing 1. This arrangement allows the operating cavity 19 to house all components, ensuring that all components are housed within the housing 1 and resulting in a simple overall design for the equipment.

[0053] Of course, the above description is not limiting, and in some alternative embodiments, the operating cavity 19 may be omitted.

[0054] like Figure 2 As shown, a microwave generator 10 and a circulating fan 11 are installed inside the operating cavity 19. This arrangement allows the microwave generator 10 to further stimulate water molecule resonance, accelerate diffusion, and significantly improve drying efficiency, thus playing a role in auxiliary drying.

[0055] Of course, the above description is not limiting, and in some alternative embodiments, the microwave generator 10 may be omitted.

[0056] Usage: Pass the battery electrode 6 through the guide roller 4, and wind both ends onto the take-up and unwinding device 5. Set the process parameters through the control panel. After closing the oven door, the inside of the chamber 1 is evacuated. The electric heater heats the inside of the oven to the set temperature. The take-up and unwinding device 5 performs unwinding and winding simultaneously. The correction sensor 12 controls the correction roller 13 to correct the deviation in real time during the take-up and unwinding process. When the forward rotation ends, it automatically switches to reverse rotation. According to the baking process, this process is repeated multiple times. During the baking process, vacuuming and nitrogen filling are alternately performed. At the same time, the microwave generator 10 assists in stimulating water molecule resonance, accelerating the diffusion of moisture and greatly improving the drying efficiency. During the process of filling nitrogen into the air duct 17, the circulating fan 11 makes the nitrogen move in the chamber 1. Through the cooperation of the guide plate 15 and the slit air outlet structure 16, the nitrogen flows directionally in the whole oven. During the vacuuming process, the moisture content in the extracted gas is detected in real time. When the moisture content is lower than the set target value, the temperature is automatically reduced and the baking process ends.

[0057] Using this equipment helps to distribute the nitrogen gas in the drying oven more evenly, allowing the battery electrode 6 to dry fully, and ensuring that the electrode is heated evenly during the drying process, while also ensuring that the drying effect is consistent on both the inside and outside of the electrode roll.

[0058] Although embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the present invention.

Claims

1. A vacuum drying oven for battery electrodes, characterized in that, include: The box (1) has a drying chamber (14) inside. The box (1) has a gas inlet (7) and a gas outlet (8). The gas inlet (7) and the gas outlet (8) are respectively connected to the drying chamber (14). The winding and unwinding device (5) has at least two, which are spaced apart in the drying chamber (14), and a plurality of guide rollers (4) are provided between the two winding and unwinding devices (5). The circulating fan (11) has an air inlet and an air outlet, the air inlet and the air outlet are respectively connected to the drying chamber (14), and there are multiple air outlets, which are arranged in the same circumferential direction in the drying chamber (14); A guide plate (15) is disposed inside the drying chamber (14), and the guide plate (15) has an arc-shaped guide surface facing the air outlet.

2. The vacuum drying oven for battery electrodes according to claim 1, characterized in that, The drying chamber (14) is provided with a slit air outlet structure (16) at the air outlet.

3. The vacuum drying oven for battery electrodes according to claim 1, characterized in that, The plurality of guide rollers (4) are adapted to support the battery electrodes (6) in a multilayer configuration that is sequentially connected and spaced apart.

4. The battery electrode vacuum drying oven according to claim 3, characterized in that, Also includes: Multiple air supply ducts (17) are respectively arranged between the multilayer battery electrode sheets (6), and the air supply ducts (17) are connected to the air inlet or air outlet of the circulating fan (11).

5. The vacuum drying oven for battery electrodes according to claim 4, characterized in that, The air supply duct (17) has multiple vents (18) around its circumference.

6. The battery electrode vacuum drying oven according to claim 3, characterized in that, A correction system is provided on both sides of the battery electrode (6). The correction system includes a correction sensor (12) and a correction roller (13). The correction sensor (12) and the correction roller (13) are arranged opposite to each other.

7. The vacuum drying oven for battery electrodes according to claim 1, characterized in that, The box (1) is provided with an insulation layer (2) and a heating layer (3) inside, with the insulation layer (2) on the outside of the heating layer (3).

8. The vacuum drying oven for battery electrodes according to claim 1, characterized in that, A moisture detection system (9) is installed below the gas outlet (8).

9. The vacuum drying oven for battery electrodes according to claim 1, characterized in that, An operating cavity (19) is provided inside the housing (1).

10. The battery electrode vacuum drying oven according to claim 9, characterized in that, The operating cavity (19) is equipped with a microwave generator (10) and a circulating fan (11).

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